[RFC,V2,1/2] ACPI/PCI: Match PCI config space accessors against platfrom specific ECAM quirks

Commit Message

Dongdong Liu June 13, 2016, 1:02 p.m. UTC

From: Tomasz Nowicki <[e-mail]>

Some platforms may not be fully compliant with generic set of PCI config
accessors. For these cases we implement the way to overwrite accessors
set. Algorithm traverses available quirk list, matches against
<oem_id, oem_table_id, domain, bus number> tuple and returns corresponding
PCI config ops. oem_id and oem_table_id come from MCFG table standard header.
All quirks can be defined using DECLARE_ACPI_MCFG_FIXUP() macro and
kept self contained. Example:

/* Custom PCI config ops */
static struct pci_generic_ecam_ops foo_pci_ops = {
	.bus_shift	= 24,
	.pci_ops = {
		.map_bus = pci_ecam_map_bus,
		.read = foo_ecam_config_read,
		.write = foo_ecam_config_write,
	}
};

DECLARE_ACPI_MCFG_FIXUP(&foo_pci_ops, <oem_id_str>, <oem_table_id>, <domain_nr>, <bus_nr>);

Signed-off-by: Tomasz Nowicki <[e-mail]>
Signed-off-by: Dongdong Liu <[e-mail]>
---
 drivers/acpi/pci_mcfg.c           | 41 ++++++++++++++++++++++++++++++++++++---
 include/asm-generic/vmlinux.lds.h |  7 +++++++
 include/linux/pci-acpi.h          | 20 +++++++++++++++++++
 3 files changed, 65 insertions(+), 3 deletions(-)

Comments

Gabriele Paoloni June 13, 2016, 1:54 p.m. UTC | #1

Hi Tomasz, Jon

> -----Original Message-----
> From: liudongdong (C)
> Sent: 13 June 2016 14:02
> To: [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail]; [e-mail];
> [e-mail]
> Cc: [e-mail]; [e-mail];
> [e-mail]; [e-mail]; Wangyijing;
> [e-mail]; [e-mail]; linux-
> [e-mail]; [e-mail]; linux-
> [e-mail]; [e-mail]; linaro-
> [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail]; liudongdong (C);
> [e-mail]; Gabriele Paoloni; Chenxin (Charles); Linuxarm
> Subject: [RFC PATCH V2 1/2] ACPI/PCI: Match PCI config space accessors
> against platfrom specific ECAM quirks
> 
> From: Tomasz Nowicki <[e-mail]>
> 
> Some platforms may not be fully compliant with generic set of PCI
> config
> accessors. For these cases we implement the way to overwrite accessors
> set. Algorithm traverses available quirk list, matches against
> <oem_id, oem_table_id, domain, bus number> tuple and returns
> corresponding
> PCI config ops. oem_id and oem_table_id come from MCFG table standard
> header.
> All quirks can be defined using DECLARE_ACPI_MCFG_FIXUP() macro and
> kept self contained. Example:
> 
> /* Custom PCI config ops */
> static struct pci_generic_ecam_ops foo_pci_ops = {
> 	.bus_shift	= 24,
> 	.pci_ops = {
> 		.map_bus = pci_ecam_map_bus,
> 		.read = foo_ecam_config_read,
> 		.write = foo_ecam_config_write,
> 	}
> };
> 
> DECLARE_ACPI_MCFG_FIXUP(&foo_pci_ops, <oem_id_str>, <oem_table_id>,
> <domain_nr>, <bus_nr>);
> 
> Signed-off-by: Tomasz Nowicki <[e-mail]>
> Signed-off-by: Dongdong Liu <[e-mail]>
> ---
>  drivers/acpi/pci_mcfg.c           | 41
> ++++++++++++++++++++++++++++++++++++---
>  include/asm-generic/vmlinux.lds.h |  7 +++++++
>  include/linux/pci-acpi.h          | 20 +++++++++++++++++++
>  3 files changed, 65 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
> index d3c3e85..49612b3 100644
> --- a/drivers/acpi/pci_mcfg.c
> +++ b/drivers/acpi/pci_mcfg.c
> @@ -22,6 +22,10 @@
>  #include <linux/kernel.h>
>  #include <linux/pci.h>
>  #include <linux/pci-acpi.h>
> +#include <linux/pci-ecam.h>
> +
> +/* Root pointer to the mapped MCFG table */
> +static struct acpi_table_mcfg *mcfg_table;
> 
>  /* Structure to hold entries from the MCFG table */
>  struct mcfg_entry {
> @@ -35,6 +39,38 @@ struct mcfg_entry {
>  /* List to save mcfg entries */
>  static LIST_HEAD(pci_mcfg_list);
> 
> +extern struct pci_cfg_fixup __start_acpi_mcfg_fixups[];
> +extern struct pci_cfg_fixup __end_acpi_mcfg_fixups[];
> +
> +struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root)
> +{
> +	int bus_num = root->secondary.start;
> +	int domain = root->segment;
> +	struct pci_cfg_fixup *f;
> +
> +	if (!mcfg_table)
> +		return &pci_generic_ecam_ops;
> +
> +	/*
> +	 * Match against platform specific quirks and return
> corresponding
> +	 * CAM ops.
> +	 *
> +	 * First match against PCI topology <domain:bus> then use OEM ID
> and
> +	 * OEM revision from MCFG table standard header.
> +	 */
> +	for (f = __start_acpi_mcfg_fixups; f < __end_acpi_mcfg_fixups;
> f++) {
> +		if ((f->domain == domain || f->domain ==
> PCI_MCFG_DOMAIN_ANY) &&
> +		    (f->bus_num == bus_num || f->bus_num ==
> PCI_MCFG_BUS_ANY) &&
> +		    (!strncmp(f->oem_id, mcfg_table->header.oem_id,
> +			      ACPI_OEM_ID_SIZE)) &&
> +		    (!strncmp(f->oem_table_id, mcfg_table-
> >header.oem_table_id,
> +			      ACPI_OEM_TABLE_ID_SIZE)))

As you can see here Liudongdong has replaced oem_revision with
oem_table_id.

Now it seems that there are some platforms that have already shipped
using a matching based on the oem_revision (right Jon?)

However I guess that if in FW they have defined oem_table_id properly
they should be able to use this mechanism without needing to a FW update.

Can these vendors confirm this?

Tomasz do you think this can work for Cavium Thunder?

Thanks

Gab


> +			return f->ops;
> +	}
> +	/* No quirks, use ECAM */
> +	return &pci_generic_ecam_ops;
> +}
> +
>  phys_addr_t pci_mcfg_lookup(u16 seg, struct resource *bus_res)
>  {
>  	struct mcfg_entry *e;
> @@ -54,7 +90,6 @@ phys_addr_t pci_mcfg_lookup(u16 seg, struct resource
> *bus_res)
> 
>  static __init int pci_mcfg_parse(struct acpi_table_header *header)
>  {
> -	struct acpi_table_mcfg *mcfg;
>  	struct acpi_mcfg_allocation *mptr;
>  	struct mcfg_entry *e, *arr;
>  	int i, n;
> @@ -64,8 +99,8 @@ static __init int pci_mcfg_parse(struct
> acpi_table_header *header)
> 
>  	n = (header->length - sizeof(struct acpi_table_mcfg)) /
>  					sizeof(struct acpi_mcfg_allocation);
> -	mcfg = (struct acpi_table_mcfg *)header;
> -	mptr = (struct acpi_mcfg_allocation *) &mcfg[1];
> +	mcfg_table = (struct acpi_table_mcfg *)header;
> +	mptr = (struct acpi_mcfg_allocation *) &mcfg_table[1];
> 
>  	arr = kcalloc(n, sizeof(*arr), GFP_KERNEL);
>  	if (!arr)
> diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-
> generic/vmlinux.lds.h
> index 6a67ab9..43604fc 100644
> --- a/include/asm-generic/vmlinux.lds.h
> +++ b/include/asm-generic/vmlinux.lds.h
> @@ -300,6 +300,13 @@
>  		VMLINUX_SYMBOL(__end_pci_fixups_suspend_late) = .;	\
>  	}								\
>  									\
> +	/* ACPI MCFG quirks */						\
> +	.acpi_fixup        : AT(ADDR(.acpi_fixup) - LOAD_OFFSET) {	\
> +		VMLINUX_SYMBOL(__start_acpi_mcfg_fixups) = .;		\
> +		*(.acpi_fixup_mcfg)					\
> +		VMLINUX_SYMBOL(__end_acpi_mcfg_fixups) = .;		\
> +	}								\
> +									\
>  	/* Built-in firmware blobs */					\
>  	.builtin_fw        : AT(ADDR(.builtin_fw) - LOAD_OFFSET) {	\
>  		VMLINUX_SYMBOL(__start_builtin_fw) = .;			\
> diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
> index 7d63a66..088a1da 100644
> --- a/include/linux/pci-acpi.h
> +++ b/include/linux/pci-acpi.h
> @@ -25,6 +25,7 @@ static inline acpi_status
> pci_acpi_remove_pm_notifier(struct acpi_device *dev)
>  extern phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle);
> 
>  extern phys_addr_t pci_mcfg_lookup(u16 domain, struct resource
> *bus_res);
> +extern struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root
> *root);
> 
>  static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev
> *pdev)
>  {
> @@ -72,6 +73,25 @@ struct acpi_pci_root_ops {
>  	int (*prepare_resources)(struct acpi_pci_root_info *info);
>  };
> 
> +struct pci_cfg_fixup {
> +	struct pci_ecam_ops *ops;
> +	char *oem_id;
> +	char *oem_table_id;
> +	int domain;
> +	int bus_num;
> +};
> +
> +#define PCI_MCFG_DOMAIN_ANY	-1
> +#define PCI_MCFG_BUS_ANY	-1
> +
> +/* Designate a routine to fix up buggy MCFG */
> +#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, dom, bus)
> 	\
> +	static const struct pci_cfg_fixup				\
> +	__mcfg_fixup_##oem_id##oem_table_id##dom##bus			\
> +	__used	__attribute__((__section__(".acpi_fixup_mcfg"),
> 	\
> +				aligned((sizeof(void *))))) =		\
> +	{ ops, oem_id, oem_table_id, dom, bus };
> +
>  extern int acpi_pci_probe_root_resources(struct acpi_pci_root_info
> *info);
>  extern struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
>  					    struct acpi_pci_root_ops *ops,
> --
> 1.9.1

Sinan Kaya June 13, 2016, 2:02 p.m. UTC | #2

On 6/13/2016 9:54 AM, Gabriele Paoloni wrote:
> As you can see here Liudongdong has replaced oem_revision with
> oem_table_id.
> 
> Now it seems that there are some platforms that have already shipped
> using a matching based on the oem_revision (right Jon?)
> 
> However I guess that if in FW they have defined oem_table_id properly
> they should be able to use this mechanism without needing to a FW update.
> 
> Can these vendors confirm this?
> 
> Tomasz do you think this can work for Cavium Thunder?
> 
> Thanks
> 
> Gab

Why not have all three of them? 

The initial approach was OEM id and revision id. 

Jeff Hugo indicated that addition (not removing any other fields) of table id
would make more sense.

Gabriele Paoloni June 13, 2016, 2:29 p.m. UTC | #3

Hi Sinan

> -----Original Message-----
> From: Sinan Kaya [mailto:[e-mail]]
> Sent: 13 June 2016 15:03
> To: Gabriele Paoloni; liudongdong (C); [e-mail];
> [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail]
> Cc: [e-mail]; [e-mail];
> [e-mail]; [e-mail]; Wangyijing;
> [e-mail]; [e-mail]; linux-
> [e-mail]; [e-mail]; linux-
> [e-mail]; [e-mail]; linaro-
> [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail]; [e-mail]; Chenxin
> (Charles); Linuxarm
> Subject: Re: [RFC PATCH V2 1/2] ACPI/PCI: Match PCI config space
> accessors against platfrom specific ECAM quirks
> 
> On 6/13/2016 9:54 AM, Gabriele Paoloni wrote:
> > As you can see here Liudongdong has replaced oem_revision with
> > oem_table_id.
> >
> > Now it seems that there are some platforms that have already shipped
> > using a matching based on the oem_revision (right Jon?)
> >
> > However I guess that if in FW they have defined oem_table_id properly
> > they should be able to use this mechanism without needing to a FW
> update.
> >
> > Can these vendors confirm this?
> >
> > Tomasz do you think this can work for Cavium Thunder?
> >
> > Thanks
> >
> > Gab
> 
> Why not have all three of them?
> 
> The initial approach was OEM id and revision id.
> 
> Jeff Hugo indicated that addition (not removing any other fields) of
> table id
> would make more sense.

Mmm from last email of Jeff Hugo on "[RFC PATCH 1/3] pci, acpi: Match
PCI config space accessors against platfrom specific ECAM quirks."

I quote:

 "Using the OEM revision 
 field does not seem to be appropriate since these are different 
 platforms and the revision field appears to be for the purpose of 
 tracking differences within a single platform.  Therefore, Cov is 
 proposing using the OEM table id as a mechanism to distinguish
 platform A (needs quirk applied) vs platform B (no quirks) from the
 same OEM."

So it looks to me that he pointed out that using the OEM revision field
is wrong...and this is why I have asked if replacing it with the table
id can work for other vendors....

Thanks

Gab


> 
> --
> Sinan Kaya
> Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center,
> Inc.
> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a
> Linux Foundation Collaborative Project

Sinan Kaya June 13, 2016, 3:12 p.m. UTC | #4

On 2016-06-13 10:29, Gabriele Paoloni wrote:
> Hi Sinan
> 
>> -----Original Message-----
>> From: Sinan Kaya [mailto:[e-mail]]
>> Sent: 13 June 2016 15:03
>> To: Gabriele Paoloni; liudongdong (C); [e-mail];
>> [e-mail]; [e-mail]; [e-mail];
>> [e-mail]; [e-mail]; [e-mail];
>> [e-mail]; [e-mail]
>> Cc: [e-mail]; [e-mail];
>> [e-mail]; [e-mail]; Wangyijing;
>> [e-mail]; [e-mail]; linux-
>> [e-mail]; [e-mail]; linux-
>> [e-mail]; [e-mail]; linaro-
>> [e-mail]; [e-mail]; [e-mail];
>> [e-mail]; [e-mail]; [e-mail]; Chenxin
>> (Charles); Linuxarm
>> Subject: Re: [RFC PATCH V2 1/2] ACPI/PCI: Match PCI config space
>> accessors against platfrom specific ECAM quirks
>> 
>> On 6/13/2016 9:54 AM, Gabriele Paoloni wrote:
>> > As you can see here Liudongdong has replaced oem_revision with
>> > oem_table_id.
>> >
>> > Now it seems that there are some platforms that have already shipped
>> > using a matching based on the oem_revision (right Jon?)
>> >
>> > However I guess that if in FW they have defined oem_table_id properly
>> > they should be able to use this mechanism without needing to a FW
>> update.
>> >
>> > Can these vendors confirm this?
>> >
>> > Tomasz do you think this can work for Cavium Thunder?
>> >
>> > Thanks
>> >
>> > Gab
>> 
>> Why not have all three of them?
>> 
>> The initial approach was OEM id and revision id.
>> 
>> Jeff Hugo indicated that addition (not removing any other fields) of
>> table id
>> would make more sense.
> 
> Mmm from last email of Jeff Hugo on "[RFC PATCH 1/3] pci, acpi: Match
> PCI config space accessors against platfrom specific ECAM quirks."
> 
> I quote:
> 
>  "Using the OEM revision
>  field does not seem to be appropriate since these are different
>  platforms and the revision field appears to be for the purpose of
>  tracking differences within a single platform.  Therefore, Cov is
>  proposing using the OEM table id as a mechanism to distinguish
>  platform A (needs quirk applied) vs platform B (no quirks) from the
>  same OEM."
> 
> So it looks to me that he pointed out that using the OEM revision field
> is wrong...and this is why I have asked if replacing it with the table
> id can work for other vendors....
> 
> Thanks
> 
> Gab
> 

I had an internal discussion with jeff and cov before posting on the 
maillist.

I think there is missing info in the email.

Usage of oem id + table id + revision is ok.

Usage of oem id + revision is not ok as one oem can build multiple chips 
with the same oem id and revision id but different table id. Otherwise, 
we can run out of revisions very quickly.

> 
>> 
>> --
>> Sinan Kaya
>> Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center,
>> Inc.
>> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a
>> Linux Foundation Collaborative Project

Christopher Covington June 13, 2016, 3:47 p.m. UTC | #5

Hi Dongdong,

On 06/13/2016 09:02 AM, Dongdong Liu wrote:
> diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
> index d3c3e85..49612b3 100644
> --- a/drivers/acpi/pci_mcfg.c
> +++ b/drivers/acpi/pci_mcfg.c
> @@ -22,6 +22,10 @@
>  #include <linux/kernel.h>
>  #include <linux/pci.h>
>  #include <linux/pci-acpi.h>
> +#include <linux/pci-ecam.h>
> +
> +/* Root pointer to the mapped MCFG table */
> +static struct acpi_table_mcfg *mcfg_table;
>  
>  /* Structure to hold entries from the MCFG table */
>  struct mcfg_entry {
> @@ -35,6 +39,38 @@ struct mcfg_entry {
>  /* List to save mcfg entries */
>  static LIST_HEAD(pci_mcfg_list);
>  
> +extern struct pci_cfg_fixup __start_acpi_mcfg_fixups[];
> +extern struct pci_cfg_fixup __end_acpi_mcfg_fixups[];
> +
> +struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root)
> +{
> +	int bus_num = root->secondary.start;
> +	int domain = root->segment;
> +	struct pci_cfg_fixup *f;
> +
> +	if (!mcfg_table)
> +		return &pci_generic_ecam_ops;
> +
> +	/*
> +	 * Match against platform specific quirks and return corresponding
> +	 * CAM ops.
> +	 *
> +	 * First match against PCI topology <domain:bus> then use OEM ID and
> +	 * OEM revision from MCFG table standard header.
> +	 */
> +	for (f = __start_acpi_mcfg_fixups; f < __end_acpi_mcfg_fixups; f++) {
> +		if ((f->domain == domain || f->domain == PCI_MCFG_DOMAIN_ANY) &&
> +		    (f->bus_num == bus_num || f->bus_num == PCI_MCFG_BUS_ANY) &&
> +		    (!strncmp(f->oem_id, mcfg_table->header.oem_id,
> +			      ACPI_OEM_ID_SIZE)) &&
> +		    (!strncmp(f->oem_table_id, mcfg_table->header.oem_table_id,
> +			      ACPI_OEM_TABLE_ID_SIZE)))

This would just be a small convenience, but if the character count used here were

min(strlen(f->oem_id), ACPI_OEM_ID_SIZE)

then the parameters to DECLARE_ACPI_MCFG_FIXUP macro could be substrings and
wouldn't need to be padded out to the full length.

> +			return f->ops;
> +	}
> +	/* No quirks, use ECAM */
> +	return &pci_generic_ecam_ops;
> +}

> diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
> index 7d63a66..088a1da 100644
> --- a/include/linux/pci-acpi.h
> +++ b/include/linux/pci-acpi.h
> @@ -25,6 +25,7 @@ static inline acpi_status pci_acpi_remove_pm_notifier(struct acpi_device *dev)
>  extern phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle);
>  
>  extern phys_addr_t pci_mcfg_lookup(u16 domain, struct resource *bus_res);
> +extern struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root);
>  
>  static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev)
>  {
> @@ -72,6 +73,25 @@ struct acpi_pci_root_ops {
>  	int (*prepare_resources)(struct acpi_pci_root_info *info);
>  };
>  
> +struct pci_cfg_fixup {
> +	struct pci_ecam_ops *ops;
> +	char *oem_id;
> +	char *oem_table_id;
> +	int domain;
> +	int bus_num;
> +};
> +
> +#define PCI_MCFG_DOMAIN_ANY	-1
> +#define PCI_MCFG_BUS_ANY	-1
> +
> +/* Designate a routine to fix up buggy MCFG */
> +#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, dom, bus)	\
> +	static const struct pci_cfg_fixup				\
> +	__mcfg_fixup_##oem_id##oem_table_id##dom##bus			\

I'm not entirely sure that this is the right fix--I'm pretty blindly
following a GCC documentation suggestion [1]--but removing the first two
preprocessor concatenation operators "##" solved the following build error
for me.

include/linux/pci-acpi.h:90:2: error: pasting "__mcfg_fixup_" and ""QCOM"" does not give a valid preprocessing token
  __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
  ^
arch/arm64/kernel/pci.c:225:1: note: in expansion of macro ‘DECLARE_ACPI_MCFG_FIXUP’
 DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
 ^
arch/arm64/kernel/pci.c:225:44: error: pasting ""QCOM"" and ""QDF2432"" does not give a valid preprocessing token
 DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
                                            ^
include/linux/pci-acpi.h:90:17: note: in definition of macro ‘DECLARE_ACPI_MCFG_FIXUP’
  __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
                 ^
arch/arm64/kernel/pci.c:225:52: error: pasting ""QDF2432"" and "PCI_MCFG_DOMAIN_ANY" does not give a valid preprocessi
ng token
 DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
                                                    ^
include/linux/pci-acpi.h:90:25: note: in definition of macro ‘DECLARE_ACPI_MCFG_FIXUP’
  __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
                         ^
arch/arm64/kernel/pci.c:225:44: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before string constant
 DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
                                            ^
include/linux/pci-acpi.h:90:17: note: in definition of macro ‘DECLARE_ACPI_MCFG_FIXUP’
  __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
                 ^
make[1]: *** [arch/arm64/kernel/pci.o] Error 1
make: *** [arch/arm64/kernel] Error 2

1. https://gcc.gnu.org/onlinedocs/cpp/Concatenation.html#Concatenation

> +	__used	__attribute__((__section__(".acpi_fixup_mcfg"),		\
> +				aligned((sizeof(void *))))) =		\
> +	{ ops, oem_id, oem_table_id, dom, bus };
> +
>  extern int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info);
>  extern struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
>  					    struct acpi_pci_root_ops *ops,
> 

Thanks,
Cov

Jeffrey Hugo June 13, 2016, 3:59 p.m. UTC | #6

On 6/13/2016 9:12 AM, [e-mail] wrote:
> On 2016-06-13 10:29, Gabriele Paoloni wrote:
>> Hi Sinan
>>
>>> -----Original Message-----
>>> From: Sinan Kaya [mailto:[e-mail]]
>>> Sent: 13 June 2016 15:03
>>> To: Gabriele Paoloni; liudongdong (C); [e-mail];
>>> [e-mail]; [e-mail]; [e-mail];
>>> [e-mail]; [e-mail]; [e-mail];
>>> [e-mail]; [e-mail]
>>> Cc: [e-mail]; [e-mail];
>>> [e-mail]; [e-mail]; Wangyijing;
>>> [e-mail]; [e-mail]; linux-
>>> [e-mail]; [e-mail]; linux-
>>> [e-mail]; [e-mail]; linaro-
>>> [e-mail]; [e-mail]; [e-mail];
>>> [e-mail]; [e-mail]; [e-mail]; Chenxin
>>> (Charles); Linuxarm
>>> Subject: Re: [RFC PATCH V2 1/2] ACPI/PCI: Match PCI config space
>>> accessors against platfrom specific ECAM quirks
>>>
>>> On 6/13/2016 9:54 AM, Gabriele Paoloni wrote:
>>> > As you can see here Liudongdong has replaced oem_revision with
>>> > oem_table_id.
>>> >
>>> > Now it seems that there are some platforms that have already shipped
>>> > using a matching based on the oem_revision (right Jon?)
>>> >
>>> > However I guess that if in FW they have defined oem_table_id properly
>>> > they should be able to use this mechanism without needing to a FW
>>> update.
>>> >
>>> > Can these vendors confirm this?
>>> >
>>> > Tomasz do you think this can work for Cavium Thunder?
>>> >
>>> > Thanks
>>> >
>>> > Gab
>>>
>>> Why not have all three of them?
>>>
>>> The initial approach was OEM id and revision id.
>>>
>>> Jeff Hugo indicated that addition (not removing any other fields) of
>>> table id
>>> would make more sense.
>>
>> Mmm from last email of Jeff Hugo on "[RFC PATCH 1/3] pci, acpi: Match
>> PCI config space accessors against platfrom specific ECAM quirks."
>>
>> I quote:
>>
>>  "Using the OEM revision
>>  field does not seem to be appropriate since these are different
>>  platforms and the revision field appears to be for the purpose of
>>  tracking differences within a single platform.  Therefore, Cov is
>>  proposing using the OEM table id as a mechanism to distinguish
>>  platform A (needs quirk applied) vs platform B (no quirks) from the
>>  same OEM."
>>
>> So it looks to me that he pointed out that using the OEM revision field
>> is wrong...and this is why I have asked if replacing it with the table
>> id can work for other vendors....
>>
>> Thanks
>>
>> Gab
>>
>
> I had an internal discussion with jeff and cov before posting on the
> maillist.
>
> I think there is missing info in the email.
>
> Usage of oem id + table id + revision is ok.
>
> Usage of oem id + revision is not ok as one oem can build multiple chips
> with the same oem id and revision id but different table id. Otherwise,
> we can run out of revisions very quickly.

Agreed.

I'm sorry for the confusion.  My intent was to point out that revision 
alone appeared insufficient to address all the identified problems, but 
I believe there is still a case for using revision. Table id is useful 
for differentiating between platforms/chips.  Revision is useful for 
differentiation between different versions of a single platform/chip 
assuming the silicon is respun or some other fix is applied.  Both solve 
different scenarios, and I'm not aware of a reason why they could not be 
used together to solve all currently identified cases.

>
>>
>>>
>>> --
>>> Sinan Kaya
>>> Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center,
>>> Inc.
>>> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a
>>> Linux Foundation Collaborative Project
>
> _______________________________________________
> linux-arm-kernel mailing list
> [e-mail]
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Duc Dang June 13, 2016, 8:57 p.m. UTC | #7

On Mon, Jun 13, 2016 at 8:47 AM, Christopher Covington
<[e-mail]> wrote:
> Hi Dongdong,
>
> On 06/13/2016 09:02 AM, Dongdong Liu wrote:
>> diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
>> index d3c3e85..49612b3 100644
>> --- a/drivers/acpi/pci_mcfg.c
>> +++ b/drivers/acpi/pci_mcfg.c
>> @@ -22,6 +22,10 @@
>>  #include <linux/kernel.h>
>>  #include <linux/pci.h>
>>  #include <linux/pci-acpi.h>
>> +#include <linux/pci-ecam.h>
>> +
>> +/* Root pointer to the mapped MCFG table */
>> +static struct acpi_table_mcfg *mcfg_table;
>>
>>  /* Structure to hold entries from the MCFG table */
>>  struct mcfg_entry {
>> @@ -35,6 +39,38 @@ struct mcfg_entry {
>>  /* List to save mcfg entries */
>>  static LIST_HEAD(pci_mcfg_list);
>>
>> +extern struct pci_cfg_fixup __start_acpi_mcfg_fixups[];
>> +extern struct pci_cfg_fixup __end_acpi_mcfg_fixups[];
>> +
>> +struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root)
>> +{
>> +     int bus_num = root->secondary.start;
>> +     int domain = root->segment;
>> +     struct pci_cfg_fixup *f;
>> +
>> +     if (!mcfg_table)
>> +             return &pci_generic_ecam_ops;
>> +
>> +     /*
>> +      * Match against platform specific quirks and return corresponding
>> +      * CAM ops.
>> +      *
>> +      * First match against PCI topology <domain:bus> then use OEM ID and
>> +      * OEM revision from MCFG table standard header.
>> +      */
>> +     for (f = __start_acpi_mcfg_fixups; f < __end_acpi_mcfg_fixups; f++) {
>> +             if ((f->domain == domain || f->domain == PCI_MCFG_DOMAIN_ANY) &&
>> +                 (f->bus_num == bus_num || f->bus_num == PCI_MCFG_BUS_ANY) &&
>> +                 (!strncmp(f->oem_id, mcfg_table->header.oem_id,
>> +                           ACPI_OEM_ID_SIZE)) &&
>> +                 (!strncmp(f->oem_table_id, mcfg_table->header.oem_table_id,
>> +                           ACPI_OEM_TABLE_ID_SIZE)))
>
> This would just be a small convenience, but if the character count used here were
>
> min(strlen(f->oem_id), ACPI_OEM_ID_SIZE)
>
> then the parameters to DECLARE_ACPI_MCFG_FIXUP macro could be substrings and
> wouldn't need to be padded out to the full length.
>
>> +                     return f->ops;
>> +     }
>> +     /* No quirks, use ECAM */
>> +     return &pci_generic_ecam_ops;
>> +}
>
>> diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
>> index 7d63a66..088a1da 100644
>> --- a/include/linux/pci-acpi.h
>> +++ b/include/linux/pci-acpi.h
>> @@ -25,6 +25,7 @@ static inline acpi_status pci_acpi_remove_pm_notifier(struct acpi_device *dev)
>>  extern phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle);
>>
>>  extern phys_addr_t pci_mcfg_lookup(u16 domain, struct resource *bus_res);
>> +extern struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root);
>>
>>  static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev)
>>  {
>> @@ -72,6 +73,25 @@ struct acpi_pci_root_ops {
>>       int (*prepare_resources)(struct acpi_pci_root_info *info);
>>  };
>>
>> +struct pci_cfg_fixup {
>> +     struct pci_ecam_ops *ops;
>> +     char *oem_id;
>> +     char *oem_table_id;
>> +     int domain;
>> +     int bus_num;
>> +};
>> +
>> +#define PCI_MCFG_DOMAIN_ANY  -1
>> +#define PCI_MCFG_BUS_ANY     -1
>> +
>> +/* Designate a routine to fix up buggy MCFG */
>> +#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, dom, bus) \
>> +     static const struct pci_cfg_fixup                               \
>> +     __mcfg_fixup_##oem_id##oem_table_id##dom##bus                   \
>
> I'm not entirely sure that this is the right fix--I'm pretty blindly
> following a GCC documentation suggestion [1]--but removing the first two
> preprocessor concatenation operators "##" solved the following build error
> for me.
>
> include/linux/pci-acpi.h:90:2: error: pasting "__mcfg_fixup_" and ""QCOM"" does not give a valid preprocessing token
>   __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \

I think the problem is gcc is not happy with quoted string when
processing these tokens
(""QCOM"", the extra "" are added by gcc). So should we not concat
string tokens and
use the fixup definition in v1 of this RFC:
/* Designate a routine to fix up buggy MCFG */
#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, rev, dom, bus)             \
        static const struct pci_cfg_fixup __mcfg_fixup_##system##dom##bus\
         __used __attribute__((__section__(".acpi_fixup_mcfg"),         \
                                aligned((sizeof(void *))))) =           \
        { ops, oem_id, rev, dom, bus };

Regards,
Duc Dang.


>   ^
> arch/arm64/kernel/pci.c:225:1: note: in expansion of macro ‘DECLARE_ACPI_MCFG_FIXUP’
>  DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>  ^
> arch/arm64/kernel/pci.c:225:44: error: pasting ""QCOM"" and ""QDF2432"" does not give a valid preprocessing token
>  DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>                                             ^
> include/linux/pci-acpi.h:90:17: note: in definition of macro ‘DECLARE_ACPI_MCFG_FIXUP’
>   __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>                  ^
> arch/arm64/kernel/pci.c:225:52: error: pasting ""QDF2432"" and "PCI_MCFG_DOMAIN_ANY" does not give a valid preprocessi
> ng token
>  DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>                                                     ^
> include/linux/pci-acpi.h:90:25: note: in definition of macro ‘DECLARE_ACPI_MCFG_FIXUP’
>   __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>                          ^
> arch/arm64/kernel/pci.c:225:44: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before string constant
>  DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>                                             ^
> include/linux/pci-acpi.h:90:17: note: in definition of macro ‘DECLARE_ACPI_MCFG_FIXUP’
>   __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>                  ^
> make[1]: *** [arch/arm64/kernel/pci.o] Error 1
> make: *** [arch/arm64/kernel] Error 2
>
> 1. https://gcc.gnu.org/onlinedocs/cpp/Concatenation.html#Concatenation
>
>> +     __used  __attribute__((__section__(".acpi_fixup_mcfg"),         \
>> +                             aligned((sizeof(void *))))) =           \
>> +     { ops, oem_id, oem_table_id, dom, bus };
>> +
>>  extern int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info);
>>  extern struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
>>                                           struct acpi_pci_root_ops *ops,
>>
>
> Thanks,
> Cov
>
> --
> Qualcomm Innovation Center, Inc.
> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
> a Linux Foundation Collaborative Project

Duc Dang June 13, 2016, 9:07 p.m. UTC | #8

On Mon, Jun 13, 2016 at 8:59 AM, Jeffrey Hugo <[e-mail]> wrote:
> On 6/13/2016 9:12 AM, [e-mail] wrote:
>>
>> On 2016-06-13 10:29, Gabriele Paoloni wrote:
>>>
>>> Hi Sinan
>>>
>>>> -----Original Message-----
>>>> From: Sinan Kaya [mailto:[e-mail]]
>>>> Sent: 13 June 2016 15:03
>>>> To: Gabriele Paoloni; liudongdong (C); [e-mail];
>>>> [e-mail]; [e-mail]; [e-mail];
>>>> [e-mail]; [e-mail]; [e-mail];
>>>> [e-mail]; [e-mail]
>>>> Cc: [e-mail]; [e-mail];
>>>> [e-mail]; [e-mail]; Wangyijing;
>>>> [e-mail]; [e-mail]; linux-
>>>> [e-mail]; [e-mail]; linux-
>>>> [e-mail]; [e-mail]; linaro-
>>>> [e-mail]; [e-mail]; [e-mail];
>>>> [e-mail]; [e-mail]; [e-mail]; Chenxin
>>>> (Charles); Linuxarm
>>>> Subject: Re: [RFC PATCH V2 1/2] ACPI/PCI: Match PCI config space
>>>> accessors against platfrom specific ECAM quirks
>>>>
>>>> On 6/13/2016 9:54 AM, Gabriele Paoloni wrote:
>>>> > As you can see here Liudongdong has replaced oem_revision with
>>>> > oem_table_id.
>>>> >
>>>> > Now it seems that there are some platforms that have already shipped
>>>> > using a matching based on the oem_revision (right Jon?)
>>>> >
>>>> > However I guess that if in FW they have defined oem_table_id properly
>>>> > they should be able to use this mechanism without needing to a FW
>>>> update.
>>>> >
>>>> > Can these vendors confirm this?
>>>> >
>>>> > Tomasz do you think this can work for Cavium Thunder?
>>>> >
>>>> > Thanks
>>>> >
>>>> > Gab
>>>>
>>>> Why not have all three of them?
>>>>
>>>> The initial approach was OEM id and revision id.
>>>>
>>>> Jeff Hugo indicated that addition (not removing any other fields) of
>>>> table id
>>>> would make more sense.
>>>
>>>
>>> Mmm from last email of Jeff Hugo on "[RFC PATCH 1/3] pci, acpi: Match
>>> PCI config space accessors against platfrom specific ECAM quirks."
>>>
>>> I quote:
>>>
>>>  "Using the OEM revision
>>>  field does not seem to be appropriate since these are different
>>>  platforms and the revision field appears to be for the purpose of
>>>  tracking differences within a single platform.  Therefore, Cov is
>>>  proposing using the OEM table id as a mechanism to distinguish
>>>  platform A (needs quirk applied) vs platform B (no quirks) from the
>>>  same OEM."
>>>
>>> So it looks to me that he pointed out that using the OEM revision field
>>> is wrong...and this is why I have asked if replacing it with the table
>>> id can work for other vendors....
>>>
>>> Thanks
>>>
>>> Gab
>>>
>>
>> I had an internal discussion with jeff and cov before posting on the
>> maillist.
>>
>> I think there is missing info in the email.
>>
>> Usage of oem id + table id + revision is ok.
>>
>> Usage of oem id + revision is not ok as one oem can build multiple chips
>> with the same oem id and revision id but different table id. Otherwise,
>> we can run out of revisions very quickly.
>
>
> Agreed.
>
> I'm sorry for the confusion.  My intent was to point out that revision alone
> appeared insufficient to address all the identified problems, but I believe
> there is still a case for using revision. Table id is useful for
> differentiating between platforms/chips.  Revision is useful for
> differentiation between different versions of a single platform/chip
> assuming the silicon is respun or some other fix is applied.  Both solve
> different scenarios, and I'm not aware of a reason why they could not be
> used together to solve all currently identified cases.

Using OEM ID + Table ID + Revision will work for X-Gene platforms as well.

Regards,
Duc Dang.
>
>>
>>>
>>>>
>>>> --
>>>> Sinan Kaya
>>>> Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center,
>>>> Inc.
>>>> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a
>>>> Linux Foundation Collaborative Project
>>
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> [e-mail]
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
>
>
> --
> Jeffrey Hugo
> Qualcomm Innovation Center, Inc.
> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux
> Foundation Collaborative Project

Dongdong Liu June 14, 2016, 5:51 a.m. UTC | #9

Hi Duc

在 2016/6/14 4:57, Duc Dang 写道:
> On Mon, Jun 13, 2016 at 8:47 AM, Christopher Covington
> <[e-mail]> wrote:
>> Hi Dongdong,
>>
>> On 06/13/2016 09:02 AM, Dongdong Liu wrote:
>>> diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
>>> index d3c3e85..49612b3 100644
>>> --- a/drivers/acpi/pci_mcfg.c
>>> +++ b/drivers/acpi/pci_mcfg.c
>>> @@ -22,6 +22,10 @@
>>>   #include <linux/kernel.h>
>>>   #include <linux/pci.h>
>>>   #include <linux/pci-acpi.h>
>>> +#include <linux/pci-ecam.h>
>>> +
>>> +/* Root pointer to the mapped MCFG table */
>>> +static struct acpi_table_mcfg *mcfg_table;
>>>
>>>   /* Structure to hold entries from the MCFG table */
>>>   struct mcfg_entry {
>>> @@ -35,6 +39,38 @@ struct mcfg_entry {
>>>   /* List to save mcfg entries */
>>>   static LIST_HEAD(pci_mcfg_list);
>>>
>>> +extern struct pci_cfg_fixup __start_acpi_mcfg_fixups[];
>>> +extern struct pci_cfg_fixup __end_acpi_mcfg_fixups[];
>>> +
>>> +struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root)
>>> +{
>>> +     int bus_num = root->secondary.start;
>>> +     int domain = root->segment;
>>> +     struct pci_cfg_fixup *f;
>>> +
>>> +     if (!mcfg_table)
>>> +             return &pci_generic_ecam_ops;
>>> +
>>> +     /*
>>> +      * Match against platform specific quirks and return corresponding
>>> +      * CAM ops.
>>> +      *
>>> +      * First match against PCI topology <domain:bus> then use OEM ID and
>>> +      * OEM revision from MCFG table standard header.
>>> +      */
>>> +     for (f = __start_acpi_mcfg_fixups; f < __end_acpi_mcfg_fixups; f++) {
>>> +             if ((f->domain == domain || f->domain == PCI_MCFG_DOMAIN_ANY) &&
>>> +                 (f->bus_num == bus_num || f->bus_num == PCI_MCFG_BUS_ANY) &&
>>> +                 (!strncmp(f->oem_id, mcfg_table->header.oem_id,
>>> +                           ACPI_OEM_ID_SIZE)) &&
>>> +                 (!strncmp(f->oem_table_id, mcfg_table->header.oem_table_id,
>>> +                           ACPI_OEM_TABLE_ID_SIZE)))
>>
>> This would just be a small convenience, but if the character count used here were
>>
>> min(strlen(f->oem_id), ACPI_OEM_ID_SIZE)
>>
>> then the parameters to DECLARE_ACPI_MCFG_FIXUP macro could be substrings and
>> wouldn't need to be padded out to the full length.
>>
>>> +                     return f->ops;
>>> +     }
>>> +     /* No quirks, use ECAM */
>>> +     return &pci_generic_ecam_ops;
>>> +}
>>
>>> diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
>>> index 7d63a66..088a1da 100644
>>> --- a/include/linux/pci-acpi.h
>>> +++ b/include/linux/pci-acpi.h
>>> @@ -25,6 +25,7 @@ static inline acpi_status pci_acpi_remove_pm_notifier(struct acpi_device *dev)
>>>   extern phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle);
>>>
>>>   extern phys_addr_t pci_mcfg_lookup(u16 domain, struct resource *bus_res);
>>> +extern struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root);
>>>
>>>   static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev)
>>>   {
>>> @@ -72,6 +73,25 @@ struct acpi_pci_root_ops {
>>>        int (*prepare_resources)(struct acpi_pci_root_info *info);
>>>   };
>>>
>>> +struct pci_cfg_fixup {
>>> +     struct pci_ecam_ops *ops;
>>> +     char *oem_id;
>>> +     char *oem_table_id;
>>> +     int domain;
>>> +     int bus_num;
>>> +};
>>> +
>>> +#define PCI_MCFG_DOMAIN_ANY  -1
>>> +#define PCI_MCFG_BUS_ANY     -1
>>> +
>>> +/* Designate a routine to fix up buggy MCFG */
>>> +#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, dom, bus) \
>>> +     static const struct pci_cfg_fixup                               \
>>> +     __mcfg_fixup_##oem_id##oem_table_id##dom##bus                   \
>>
>> I'm not entirely sure that this is the right fix--I'm pretty blindly
>> following a GCC documentation suggestion [1]--but removing the first two
>> preprocessor concatenation operators "##" solved the following build error
>> for me.
>>
>> include/linux/pci-acpi.h:90:2: error: pasting "__mcfg_fixup_" and ""QCOM"" does not give a valid preprocessing token
>>    __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>
> I think the problem is gcc is not happy with quoted string when
> processing these tokens
> (""QCOM"", the extra "" are added by gcc). So should we not concat
> string tokens and
> use the fixup definition in v1 of this RFC:
> /* Designate a routine to fix up buggy MCFG */
> #define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, rev, dom, bus)             \
>          static const struct pci_cfg_fixup __mcfg_fixup_##system##dom##bus\
>           __used __attribute__((__section__(".acpi_fixup_mcfg"),         \
>                                  aligned((sizeof(void *))))) =           \
>          { ops, oem_id, rev, dom, bus };

V1 fixup exist the redefinition error when compiling mutiple DECLARE_ACPI_MCFG_FIXUP
with the same PCI_MCFG_DOMAIN_ANY and PCI_MCFG_BUS_ANY.

#define EFI_ACPI_HISI_OEM_ID "HISI"
#define EFI_ACPI_HISI_D02_OEM_TABLE_ID "HISI-D02"
#define EFI_ACPI_HISI_D03_OEM_TABLE_ID "HISI-D03"

DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
        EFI_ACPI_HISI_D02_OEM_TABLE_ID, PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);

DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
        EFI_ACPI_HISI_D03_OEM_TABLE_ID, PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);

In file included from drivers/pci/host/pcie-hisi-acpi.c:15:0:
include/linux/pci-acpi.h:98:43: error: redefinition of '__mcfg_fixup_systemPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY'
          static const struct pci_cfg_fixup __mcfg_fixup_##system##dom##bus\
                                            ^
drivers/pci/host/pcie-hisi-acpi.c:215:1: note: in expansion of macro 'DECLARE_ACPI_MCFG_FIXUP'
  DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
  ^
include/linux/pci-acpi.h:98:43: note: previous definition of '__mcfg_fixup_systemPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY' was here
          static const struct pci_cfg_fixup __mcfg_fixup_##system##dom##bus\
                                            ^
drivers/pci/host/pcie-hisi-acpi.c:212:1: note: in expansion of macro 'DECLARE_ACPI_MCFG_FIXUP'


V2 fixup can resolve the redefinition error, but need to use macro.
We can see that the name of macro is not replace with it's value in
"__mcfg_fixup_EFI_ACPI_HISI_OEM_IDEFI_ACPI_HISI_D03_OEM_TABLE_IDPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY".

Any good idea is appreciated.

Thanks
Dongdong

>
> Regards,
> Duc Dang.
>
>
>>    ^
>> arch/arm64/kernel/pci.c:225:1: note: in expansion of macro ‘DECLARE_ACPI_MCFG_FIXUP’
>>   DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>>   ^
>> arch/arm64/kernel/pci.c:225:44: error: pasting ""QCOM"" and ""QDF2432"" does not give a valid preprocessing token
>>   DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>>                                              ^
>> include/linux/pci-acpi.h:90:17: note: in definition of macro ‘DECLARE_ACPI_MCFG_FIXUP’
>>    __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>>                   ^
>> arch/arm64/kernel/pci.c:225:52: error: pasting ""QDF2432"" and "PCI_MCFG_DOMAIN_ANY" does not give a valid preprocessi
>> ng token
>>   DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>>                                                      ^
>> include/linux/pci-acpi.h:90:25: note: in definition of macro ‘DECLARE_ACPI_MCFG_FIXUP’
>>    __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>>                           ^
>> arch/arm64/kernel/pci.c:225:44: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before string constant
>>   DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>>                                              ^
>> include/linux/pci-acpi.h:90:17: note: in definition of macro ‘DECLARE_ACPI_MCFG_FIXUP’
>>    __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>>                   ^
>> make[1]: *** [arch/arm64/kernel/pci.o] Error 1
>> make: *** [arch/arm64/kernel] Error 2
>>
>> 1. https://gcc.gnu.org/onlinedocs/cpp/Concatenation.html#Concatenation
>>
>>> +     __used  __attribute__((__section__(".acpi_fixup_mcfg"),         \
>>> +                             aligned((sizeof(void *))))) =           \
>>> +     { ops, oem_id, oem_table_id, dom, bus };
>>> +
>>>   extern int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info);
>>>   extern struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
>>>                                            struct acpi_pci_root_ops *ops,
>>>
>>
>> Thanks,
>> Cov
>>
>> --
>> Qualcomm Innovation Center, Inc.
>> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
>> a Linux Foundation Collaborative Project
>
> .
>

Duc Dang June 14, 2016, 9 a.m. UTC | #10

On Mon, Jun 13, 2016 at 10:51 PM, Dongdong Liu <[e-mail]> wrote:
> Hi Duc
>
> 在 2016/6/14 4:57, Duc Dang 写道:
>>
>> On Mon, Jun 13, 2016 at 8:47 AM, Christopher Covington
>> <[e-mail]> wrote:
>>>
>>> Hi Dongdong,
>>>
>>> On 06/13/2016 09:02 AM, Dongdong Liu wrote:
>>>>
>>>> diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
>>>> index d3c3e85..49612b3 100644
>>>> --- a/drivers/acpi/pci_mcfg.c
>>>> +++ b/drivers/acpi/pci_mcfg.c
>>>> @@ -22,6 +22,10 @@
>>>>   #include <linux/kernel.h>
>>>>   #include <linux/pci.h>
>>>>   #include <linux/pci-acpi.h>
>>>> +#include <linux/pci-ecam.h>
>>>> +
>>>> +/* Root pointer to the mapped MCFG table */
>>>> +static struct acpi_table_mcfg *mcfg_table;
>>>>
>>>>   /* Structure to hold entries from the MCFG table */
>>>>   struct mcfg_entry {
>>>> @@ -35,6 +39,38 @@ struct mcfg_entry {
>>>>   /* List to save mcfg entries */
>>>>   static LIST_HEAD(pci_mcfg_list);
>>>>
>>>> +extern struct pci_cfg_fixup __start_acpi_mcfg_fixups[];
>>>> +extern struct pci_cfg_fixup __end_acpi_mcfg_fixups[];
>>>> +
>>>> +struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root)
>>>> +{
>>>> +     int bus_num = root->secondary.start;
>>>> +     int domain = root->segment;
>>>> +     struct pci_cfg_fixup *f;
>>>> +
>>>> +     if (!mcfg_table)
>>>> +             return &pci_generic_ecam_ops;
>>>> +
>>>> +     /*
>>>> +      * Match against platform specific quirks and return corresponding
>>>> +      * CAM ops.
>>>> +      *
>>>> +      * First match against PCI topology <domain:bus> then use OEM ID
>>>> and
>>>> +      * OEM revision from MCFG table standard header.
>>>> +      */
>>>> +     for (f = __start_acpi_mcfg_fixups; f < __end_acpi_mcfg_fixups;
>>>> f++) {
>>>> +             if ((f->domain == domain || f->domain ==
>>>> PCI_MCFG_DOMAIN_ANY) &&
>>>> +                 (f->bus_num == bus_num || f->bus_num ==
>>>> PCI_MCFG_BUS_ANY) &&
>>>> +                 (!strncmp(f->oem_id, mcfg_table->header.oem_id,
>>>> +                           ACPI_OEM_ID_SIZE)) &&
>>>> +                 (!strncmp(f->oem_table_id,
>>>> mcfg_table->header.oem_table_id,
>>>> +                           ACPI_OEM_TABLE_ID_SIZE)))
>>>
>>>
>>> This would just be a small convenience, but if the character count used
>>> here were
>>>
>>> min(strlen(f->oem_id), ACPI_OEM_ID_SIZE)
>>>
>>> then the parameters to DECLARE_ACPI_MCFG_FIXUP macro could be substrings
>>> and
>>> wouldn't need to be padded out to the full length.
>>>
>>>> +                     return f->ops;
>>>> +     }
>>>> +     /* No quirks, use ECAM */
>>>> +     return &pci_generic_ecam_ops;
>>>> +}
>>>
>>>
>>>> diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
>>>> index 7d63a66..088a1da 100644
>>>> --- a/include/linux/pci-acpi.h
>>>> +++ b/include/linux/pci-acpi.h
>>>> @@ -25,6 +25,7 @@ static inline acpi_status
>>>> pci_acpi_remove_pm_notifier(struct acpi_device *dev)
>>>>   extern phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle);
>>>>
>>>>   extern phys_addr_t pci_mcfg_lookup(u16 domain, struct resource
>>>> *bus_res);
>>>> +extern struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root
>>>> *root);
>>>>
>>>>   static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev
>>>> *pdev)
>>>>   {
>>>> @@ -72,6 +73,25 @@ struct acpi_pci_root_ops {
>>>>        int (*prepare_resources)(struct acpi_pci_root_info *info);
>>>>   };
>>>>
>>>> +struct pci_cfg_fixup {
>>>> +     struct pci_ecam_ops *ops;
>>>> +     char *oem_id;
>>>> +     char *oem_table_id;
>>>> +     int domain;
>>>> +     int bus_num;
>>>> +};
>>>> +
>>>> +#define PCI_MCFG_DOMAIN_ANY  -1
>>>> +#define PCI_MCFG_BUS_ANY     -1
>>>> +
>>>> +/* Designate a routine to fix up buggy MCFG */
>>>> +#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, dom, bus) \
>>>> +     static const struct pci_cfg_fixup                               \
>>>> +     __mcfg_fixup_##oem_id##oem_table_id##dom##bus                   \
>>>
>>>
>>> I'm not entirely sure that this is the right fix--I'm pretty blindly
>>> following a GCC documentation suggestion [1]--but removing the first two
>>> preprocessor concatenation operators "##" solved the following build
>>> error
>>> for me.
>>>
>>> include/linux/pci-acpi.h:90:2: error: pasting "__mcfg_fixup_" and
>>> ""QCOM"" does not give a valid preprocessing token
>>>    __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>>
>>
>> I think the problem is gcc is not happy with quoted string when
>> processing these tokens
>> (""QCOM"", the extra "" are added by gcc). So should we not concat
>> string tokens and
>> use the fixup definition in v1 of this RFC:
>> /* Designate a routine to fix up buggy MCFG */
>> #define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, rev, dom, bus)             \
>>          static const struct pci_cfg_fixup
>> __mcfg_fixup_##system##dom##bus\
>>           __used __attribute__((__section__(".acpi_fixup_mcfg"),         \
>>                                  aligned((sizeof(void *))))) =           \
>>          { ops, oem_id, rev, dom, bus };
>
>
> V1 fixup exist the redefinition error when compiling mutiple
> DECLARE_ACPI_MCFG_FIXUP
> with the same PCI_MCFG_DOMAIN_ANY and PCI_MCFG_BUS_ANY.
>
> #define EFI_ACPI_HISI_OEM_ID "HISI"
> #define EFI_ACPI_HISI_D02_OEM_TABLE_ID "HISI-D02"
> #define EFI_ACPI_HISI_D03_OEM_TABLE_ID "HISI-D03"
>
> DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
>        EFI_ACPI_HISI_D02_OEM_TABLE_ID, PCI_MCFG_DOMAIN_ANY,
> PCI_MCFG_BUS_ANY);
>
> DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
>        EFI_ACPI_HISI_D03_OEM_TABLE_ID, PCI_MCFG_DOMAIN_ANY,
> PCI_MCFG_BUS_ANY);
>
> In file included from drivers/pci/host/pcie-hisi-acpi.c:15:0:
> include/linux/pci-acpi.h:98:43: error: redefinition of
> '__mcfg_fixup_systemPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY'
>          static const struct pci_cfg_fixup __mcfg_fixup_##system##dom##bus\
>                                            ^
> drivers/pci/host/pcie-hisi-acpi.c:215:1: note: in expansion of macro
> 'DECLARE_ACPI_MCFG_FIXUP'
>  DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
>  ^
> include/linux/pci-acpi.h:98:43: note: previous definition of
> '__mcfg_fixup_systemPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY' was here
>          static const struct pci_cfg_fixup __mcfg_fixup_##system##dom##bus\
>                                            ^
> drivers/pci/host/pcie-hisi-acpi.c:212:1: note: in expansion of macro
> 'DECLARE_ACPI_MCFG_FIXUP'
>
>
> V2 fixup can resolve the redefinition error, but need to use macro.
> We can see that the name of macro is not replace with it's value in
> "__mcfg_fixup_EFI_ACPI_HISI_OEM_IDEFI_ACPI_HISI_D03_OEM_TABLE_IDPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY".
>
> Any good idea is appreciated.
Hmmm.

I was testing # op and using min_t to get the min-len when doing
strncmp similar to Chris' suggestion (using min_t avoids type
warnings)

/* Designate a routine to fix up buggy MCFG */
#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, rev, dom, bus) \
        static const struct pci_cfg_fixup
__mcfg_fixup##oem_id##oem_table_id##rev##dom##bus\
         __used __attribute__((__section__(".acpi_fixup_mcfg"),         \
                                aligned((sizeof(void *))))) =           \
        { ops, #oem_id, #oem_table_id, rev, dom, bus };

My fixup definition:
DECLARE_ACPI_MCFG_FIXUP(&xgene_pcie_ecam_ops, APM, XGENE, 2,
                                               PCI_MCFG_DOMAIN_ANY,
PCI_MCFG_BUS_ANY);
My match condition is:
               if ((f->domain == domain || f->domain == PCI_MCFG_DOMAIN_ANY) &&
                   (f->bus_num == bus_num || f->bus_num == PCI_MCFG_BUS_ANY) &&
                   (!strncmp(f->oem_id, mcfg->header.oem_id,
                             min_t(size_t, strlen(f->oem_id),
                                   ACPI_OEM_ID_SIZE))) &&
                   (!strncmp(f->oem_table_id, mcfg->header.oem_table_id,
                             min_t(size_t, strlen(f->oem_table_id),
                                   ACPI_OEM_TABLE_ID_SIZE))) &&
                   (f->oem_revision == mcfg->header.oem_revision)) {
                       return f->ops;
               }

But this still does not work for your case as having HISI-D02 as
oem_table_id will cause error.

>
> Thanks
> Dongdong
>
>>
>> Regards,
>> Duc Dang.
>>
>>
>>>    ^
>>> arch/arm64/kernel/pci.c:225:1: note: in expansion of macro
>>> ‘DECLARE_ACPI_MCFG_FIXUP’
>>>   DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432",
>>> PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>>>   ^
>>> arch/arm64/kernel/pci.c:225:44: error: pasting ""QCOM"" and ""QDF2432""
>>> does not give a valid preprocessing token
>>>   DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432",
>>> PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>>>                                              ^
>>> include/linux/pci-acpi.h:90:17: note: in definition of macro
>>> ‘DECLARE_ACPI_MCFG_FIXUP’
>>>    __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>>>                   ^
>>> arch/arm64/kernel/pci.c:225:52: error: pasting ""QDF2432"" and
>>> "PCI_MCFG_DOMAIN_ANY" does not give a valid preprocessi
>>> ng token
>>>   DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432",
>>> PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>>>                                                      ^
>>> include/linux/pci-acpi.h:90:25: note: in definition of macro
>>> ‘DECLARE_ACPI_MCFG_FIXUP’
>>>    __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>>>                           ^
>>> arch/arm64/kernel/pci.c:225:44: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or
>>> ‘__attribute__’ before string constant
>>>   DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432",
>>> PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>>>                                              ^
>>> include/linux/pci-acpi.h:90:17: note: in definition of macro
>>> ‘DECLARE_ACPI_MCFG_FIXUP’
>>>    __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>>>                   ^
>>> make[1]: *** [arch/arm64/kernel/pci.o] Error 1
>>> make: *** [arch/arm64/kernel] Error 2
>>>
>>> 1. https://gcc.gnu.org/onlinedocs/cpp/Concatenation.html#Concatenation
>>>
>>>> +     __used  __attribute__((__section__(".acpi_fixup_mcfg"),         \
>>>> +                             aligned((sizeof(void *))))) =           \
>>>> +     { ops, oem_id, oem_table_id, dom, bus };
>>>> +
>>>>   extern int acpi_pci_probe_root_resources(struct acpi_pci_root_info
>>>> *info);
>>>>   extern struct pci_bus *acpi_pci_root_create(struct acpi_pci_root
>>>> *root,
>>>>                                            struct acpi_pci_root_ops
>>>> *ops,
>>>>
>>>
>>> Thanks,
>>> Cov
>>>
>>> --
>>> Qualcomm Innovation Center, Inc.
>>> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
>>> a Linux Foundation Collaborative Project
>>
>>
>> .
>>
>
Regards
Duc Dang.

Dongdong Liu June 14, 2016, 9:45 a.m. UTC | #11

Hi Duc

在 2016/6/14 17:00, Duc Dang 写道:
> On Mon, Jun 13, 2016 at 10:51 PM, Dongdong Liu <[e-mail]> wrote:
>> Hi Duc
>>
>> 在 2016/6/14 4:57, Duc Dang 写道:
>>>
>>> On Mon, Jun 13, 2016 at 8:47 AM, Christopher Covington
>>> <[e-mail]> wrote:
>>>>
>>>> Hi Dongdong,
>>>>
>>>> On 06/13/2016 09:02 AM, Dongdong Liu wrote:
>>>>>
>>>>> diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
>>>>> index d3c3e85..49612b3 100644
>>>>> --- a/drivers/acpi/pci_mcfg.c
>>>>> +++ b/drivers/acpi/pci_mcfg.c
>>>>> @@ -22,6 +22,10 @@
>>>>>    #include <linux/kernel.h>
>>>>>    #include <linux/pci.h>
>>>>>    #include <linux/pci-acpi.h>
>>>>> +#include <linux/pci-ecam.h>
>>>>> +
>>>>> +/* Root pointer to the mapped MCFG table */
>>>>> +static struct acpi_table_mcfg *mcfg_table;
>>>>>
>>>>>    /* Structure to hold entries from the MCFG table */
>>>>>    struct mcfg_entry {
>>>>> @@ -35,6 +39,38 @@ struct mcfg_entry {
>>>>>    /* List to save mcfg entries */
>>>>>    static LIST_HEAD(pci_mcfg_list);
>>>>>
>>>>> +extern struct pci_cfg_fixup __start_acpi_mcfg_fixups[];
>>>>> +extern struct pci_cfg_fixup __end_acpi_mcfg_fixups[];
>>>>> +
>>>>> +struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root)
>>>>> +{
>>>>> +     int bus_num = root->secondary.start;
>>>>> +     int domain = root->segment;
>>>>> +     struct pci_cfg_fixup *f;
>>>>> +
>>>>> +     if (!mcfg_table)
>>>>> +             return &pci_generic_ecam_ops;
>>>>> +
>>>>> +     /*
>>>>> +      * Match against platform specific quirks and return corresponding
>>>>> +      * CAM ops.
>>>>> +      *
>>>>> +      * First match against PCI topology <domain:bus> then use OEM ID
>>>>> and
>>>>> +      * OEM revision from MCFG table standard header.
>>>>> +      */
>>>>> +     for (f = __start_acpi_mcfg_fixups; f < __end_acpi_mcfg_fixups;
>>>>> f++) {
>>>>> +             if ((f->domain == domain || f->domain ==
>>>>> PCI_MCFG_DOMAIN_ANY) &&
>>>>> +                 (f->bus_num == bus_num || f->bus_num ==
>>>>> PCI_MCFG_BUS_ANY) &&
>>>>> +                 (!strncmp(f->oem_id, mcfg_table->header.oem_id,
>>>>> +                           ACPI_OEM_ID_SIZE)) &&
>>>>> +                 (!strncmp(f->oem_table_id,
>>>>> mcfg_table->header.oem_table_id,
>>>>> +                           ACPI_OEM_TABLE_ID_SIZE)))
>>>>
>>>>
>>>> This would just be a small convenience, but if the character count used
>>>> here were
>>>>
>>>> min(strlen(f->oem_id), ACPI_OEM_ID_SIZE)
>>>>
>>>> then the parameters to DECLARE_ACPI_MCFG_FIXUP macro could be substrings
>>>> and
>>>> wouldn't need to be padded out to the full length.
>>>>
>>>>> +                     return f->ops;
>>>>> +     }
>>>>> +     /* No quirks, use ECAM */
>>>>> +     return &pci_generic_ecam_ops;
>>>>> +}
>>>>
>>>>
>>>>> diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
>>>>> index 7d63a66..088a1da 100644
>>>>> --- a/include/linux/pci-acpi.h
>>>>> +++ b/include/linux/pci-acpi.h
>>>>> @@ -25,6 +25,7 @@ static inline acpi_status
>>>>> pci_acpi_remove_pm_notifier(struct acpi_device *dev)
>>>>>    extern phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle);
>>>>>
>>>>>    extern phys_addr_t pci_mcfg_lookup(u16 domain, struct resource
>>>>> *bus_res);
>>>>> +extern struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root
>>>>> *root);
>>>>>
>>>>>    static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev
>>>>> *pdev)
>>>>>    {
>>>>> @@ -72,6 +73,25 @@ struct acpi_pci_root_ops {
>>>>>         int (*prepare_resources)(struct acpi_pci_root_info *info);
>>>>>    };
>>>>>
>>>>> +struct pci_cfg_fixup {
>>>>> +     struct pci_ecam_ops *ops;
>>>>> +     char *oem_id;
>>>>> +     char *oem_table_id;
>>>>> +     int domain;
>>>>> +     int bus_num;
>>>>> +};
>>>>> +
>>>>> +#define PCI_MCFG_DOMAIN_ANY  -1
>>>>> +#define PCI_MCFG_BUS_ANY     -1
>>>>> +
>>>>> +/* Designate a routine to fix up buggy MCFG */
>>>>> +#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, dom, bus) \
>>>>> +     static const struct pci_cfg_fixup                               \
>>>>> +     __mcfg_fixup_##oem_id##oem_table_id##dom##bus                   \
>>>>
>>>>
>>>> I'm not entirely sure that this is the right fix--I'm pretty blindly
>>>> following a GCC documentation suggestion [1]--but removing the first two
>>>> preprocessor concatenation operators "##" solved the following build
>>>> error
>>>> for me.
>>>>
>>>> include/linux/pci-acpi.h:90:2: error: pasting "__mcfg_fixup_" and
>>>> ""QCOM"" does not give a valid preprocessing token
>>>>     __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>>>
>>>
>>> I think the problem is gcc is not happy with quoted string when
>>> processing these tokens
>>> (""QCOM"", the extra "" are added by gcc). So should we not concat
>>> string tokens and
>>> use the fixup definition in v1 of this RFC:
>>> /* Designate a routine to fix up buggy MCFG */
>>> #define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, rev, dom, bus)             \
>>>           static const struct pci_cfg_fixup
>>> __mcfg_fixup_##system##dom##bus\
>>>            __used __attribute__((__section__(".acpi_fixup_mcfg"),         \
>>>                                   aligned((sizeof(void *))))) =           \
>>>           { ops, oem_id, rev, dom, bus };
>>
>>
>> V1 fixup exist the redefinition error when compiling mutiple
>> DECLARE_ACPI_MCFG_FIXUP
>> with the same PCI_MCFG_DOMAIN_ANY and PCI_MCFG_BUS_ANY.
>>
>> #define EFI_ACPI_HISI_OEM_ID "HISI"
>> #define EFI_ACPI_HISI_D02_OEM_TABLE_ID "HISI-D02"
>> #define EFI_ACPI_HISI_D03_OEM_TABLE_ID "HISI-D03"
>>
>> DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
>>         EFI_ACPI_HISI_D02_OEM_TABLE_ID, PCI_MCFG_DOMAIN_ANY,
>> PCI_MCFG_BUS_ANY);
>>
>> DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
>>         EFI_ACPI_HISI_D03_OEM_TABLE_ID, PCI_MCFG_DOMAIN_ANY,
>> PCI_MCFG_BUS_ANY);
>>
>> In file included from drivers/pci/host/pcie-hisi-acpi.c:15:0:
>> include/linux/pci-acpi.h:98:43: error: redefinition of
>> '__mcfg_fixup_systemPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY'
>>           static const struct pci_cfg_fixup __mcfg_fixup_##system##dom##bus\
>>                                             ^
>> drivers/pci/host/pcie-hisi-acpi.c:215:1: note: in expansion of macro
>> 'DECLARE_ACPI_MCFG_FIXUP'
>>   DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
>>   ^
>> include/linux/pci-acpi.h:98:43: note: previous definition of
>> '__mcfg_fixup_systemPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY' was here
>>           static const struct pci_cfg_fixup __mcfg_fixup_##system##dom##bus\
>>                                             ^
>> drivers/pci/host/pcie-hisi-acpi.c:212:1: note: in expansion of macro
>> 'DECLARE_ACPI_MCFG_FIXUP'
>>
>>
>> V2 fixup can resolve the redefinition error, but need to use macro.
>> We can see that the name of macro is not replace with it's value in
>> "__mcfg_fixup_EFI_ACPI_HISI_OEM_IDEFI_ACPI_HISI_D03_OEM_TABLE_IDPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY".
>>
>> Any good idea is appreciated.
> Hmmm.
>
> I was testing # op and using min_t to get the min-len when doing
> strncmp similar to Chris' suggestion (using min_t avoids type
> warnings)
>
> /* Designate a routine to fix up buggy MCFG */
> #define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, rev, dom, bus) \
>          static const struct pci_cfg_fixup
> __mcfg_fixup##oem_id##oem_table_id##rev##dom##bus\
>           __used __attribute__((__section__(".acpi_fixup_mcfg"),         \
>                                  aligned((sizeof(void *))))) =           \

>          { ops, #oem_id, #oem_table_id, rev, dom, bus };


This should change to { ops, oem_id, oem_table_id, rev, dom, bus };
‘#’ is not need.

>
> My fixup definition:
> DECLARE_ACPI_MCFG_FIXUP(&xgene_pcie_ecam_ops, APM, XGENE, 2,
>                                                 PCI_MCFG_DOMAIN_ANY,
> PCI_MCFG_BUS_ANY);
> My match condition is:
>                 if ((f->domain == domain || f->domain == PCI_MCFG_DOMAIN_ANY) &&
>                     (f->bus_num == bus_num || f->bus_num == PCI_MCFG_BUS_ANY) &&
>                     (!strncmp(f->oem_id, mcfg->header.oem_id,
>                               min_t(size_t, strlen(f->oem_id),
>                                     ACPI_OEM_ID_SIZE))) &&
>                     (!strncmp(f->oem_table_id, mcfg->header.oem_table_id,
>                               min_t(size_t, strlen(f->oem_table_id),
>                                     ACPI_OEM_TABLE_ID_SIZE))) &&
>                     (f->oem_revision == mcfg->header.oem_revision)) {
>                         return f->ops;
>                 }
>
> But this still does not work for your case as having HISI-D02 as
> oem_table_id will cause error.

In my case, I have tested  and it worked ok.
Could you show the detail error information that you met?

Thanks
Dongdong
>
>>
>> Thanks
>> Dongdong
>>
>>>
>>> Regards,
>>> Duc Dang.
>>>
>>>
>>>>     ^
>>>> arch/arm64/kernel/pci.c:225:1: note: in expansion of macro
>>>> ‘DECLARE_ACPI_MCFG_FIXUP’
>>>>    DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432",
>>>> PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>>>>    ^
>>>> arch/arm64/kernel/pci.c:225:44: error: pasting ""QCOM"" and ""QDF2432""
>>>> does not give a valid preprocessing token
>>>>    DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432",
>>>> PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>>>>                                               ^
>>>> include/linux/pci-acpi.h:90:17: note: in definition of macro
>>>> ‘DECLARE_ACPI_MCFG_FIXUP’
>>>>     __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>>>>                    ^
>>>> arch/arm64/kernel/pci.c:225:52: error: pasting ""QDF2432"" and
>>>> "PCI_MCFG_DOMAIN_ANY" does not give a valid preprocessi
>>>> ng token
>>>>    DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432",
>>>> PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>>>>                                                       ^
>>>> include/linux/pci-acpi.h:90:25: note: in definition of macro
>>>> ‘DECLARE_ACPI_MCFG_FIXUP’
>>>>     __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>>>>                            ^
>>>> arch/arm64/kernel/pci.c:225:44: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or
>>>> ‘__attribute__’ before string constant
>>>>    DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432",
>>>> PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>>>>                                               ^
>>>> include/linux/pci-acpi.h:90:17: note: in definition of macro
>>>> ‘DECLARE_ACPI_MCFG_FIXUP’
>>>>     __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>>>>                    ^
>>>> make[1]: *** [arch/arm64/kernel/pci.o] Error 1
>>>> make: *** [arch/arm64/kernel] Error 2
>>>>
>>>> 1. https://gcc.gnu.org/onlinedocs/cpp/Concatenation.html#Concatenation
>>>>
>>>>> +     __used  __attribute__((__section__(".acpi_fixup_mcfg"),         \
>>>>> +                             aligned((sizeof(void *))))) =           \
>>>>> +     { ops, oem_id, oem_table_id, dom, bus };
>>>>> +
>>>>>    extern int acpi_pci_probe_root_resources(struct acpi_pci_root_info
>>>>> *info);
>>>>>    extern struct pci_bus *acpi_pci_root_create(struct acpi_pci_root
>>>>> *root,
>>>>>                                             struct acpi_pci_root_ops
>>>>> *ops,
>>>>>
>>>>
>>>> Thanks,
>>>> Cov
>>>>
>>>> --
>>>> Qualcomm Innovation Center, Inc.
>>>> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
>>>> a Linux Foundation Collaborative Project
>>>
>>>
>>> .
>>>
>>
> Regards
> Duc Dang.
>
> .
>

Tomasz Nowicki June 14, 2016, 11:52 a.m. UTC | #12

On 14.06.2016 11:45, Dongdong Liu wrote:
> Hi Duc
>
> 在 2016/6/14 17:00, Duc Dang 写道:
>> On Mon, Jun 13, 2016 at 10:51 PM, Dongdong Liu
>> <[e-mail]> wrote:
>>> Hi Duc
>>>
>>> 在 2016/6/14 4:57, Duc Dang 写道:
>>>>
>>>> On Mon, Jun 13, 2016 at 8:47 AM, Christopher Covington
>>>> <[e-mail]> wrote:
>>>>>
>>>>> Hi Dongdong,
>>>>>
>>>>> On 06/13/2016 09:02 AM, Dongdong Liu wrote:
>>>>>>
>>>>>> diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
>>>>>> index d3c3e85..49612b3 100644
>>>>>> --- a/drivers/acpi/pci_mcfg.c
>>>>>> +++ b/drivers/acpi/pci_mcfg.c
>>>>>> @@ -22,6 +22,10 @@
>>>>>>    #include <linux/kernel.h>
>>>>>>    #include <linux/pci.h>
>>>>>>    #include <linux/pci-acpi.h>
>>>>>> +#include <linux/pci-ecam.h>
>>>>>> +
>>>>>> +/* Root pointer to the mapped MCFG table */
>>>>>> +static struct acpi_table_mcfg *mcfg_table;
>>>>>>
>>>>>>    /* Structure to hold entries from the MCFG table */
>>>>>>    struct mcfg_entry {
>>>>>> @@ -35,6 +39,38 @@ struct mcfg_entry {
>>>>>>    /* List to save mcfg entries */
>>>>>>    static LIST_HEAD(pci_mcfg_list);
>>>>>>
>>>>>> +extern struct pci_cfg_fixup __start_acpi_mcfg_fixups[];
>>>>>> +extern struct pci_cfg_fixup __end_acpi_mcfg_fixups[];
>>>>>> +
>>>>>> +struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root)
>>>>>> +{
>>>>>> +     int bus_num = root->secondary.start;
>>>>>> +     int domain = root->segment;
>>>>>> +     struct pci_cfg_fixup *f;
>>>>>> +
>>>>>> +     if (!mcfg_table)
>>>>>> +             return &pci_generic_ecam_ops;
>>>>>> +
>>>>>> +     /*
>>>>>> +      * Match against platform specific quirks and return
>>>>>> corresponding
>>>>>> +      * CAM ops.
>>>>>> +      *
>>>>>> +      * First match against PCI topology <domain:bus> then use
>>>>>> OEM ID
>>>>>> and
>>>>>> +      * OEM revision from MCFG table standard header.
>>>>>> +      */
>>>>>> +     for (f = __start_acpi_mcfg_fixups; f < __end_acpi_mcfg_fixups;
>>>>>> f++) {
>>>>>> +             if ((f->domain == domain || f->domain ==
>>>>>> PCI_MCFG_DOMAIN_ANY) &&
>>>>>> +                 (f->bus_num == bus_num || f->bus_num ==
>>>>>> PCI_MCFG_BUS_ANY) &&
>>>>>> +                 (!strncmp(f->oem_id, mcfg_table->header.oem_id,
>>>>>> +                           ACPI_OEM_ID_SIZE)) &&
>>>>>> +                 (!strncmp(f->oem_table_id,
>>>>>> mcfg_table->header.oem_table_id,
>>>>>> +                           ACPI_OEM_TABLE_ID_SIZE)))
>>>>>
>>>>>
>>>>> This would just be a small convenience, but if the character count
>>>>> used
>>>>> here were
>>>>>
>>>>> min(strlen(f->oem_id), ACPI_OEM_ID_SIZE)
>>>>>
>>>>> then the parameters to DECLARE_ACPI_MCFG_FIXUP macro could be
>>>>> substrings
>>>>> and
>>>>> wouldn't need to be padded out to the full length.
>>>>>
>>>>>> +                     return f->ops;
>>>>>> +     }
>>>>>> +     /* No quirks, use ECAM */
>>>>>> +     return &pci_generic_ecam_ops;
>>>>>> +}
>>>>>
>>>>>
>>>>>> diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
>>>>>> index 7d63a66..088a1da 100644
>>>>>> --- a/include/linux/pci-acpi.h
>>>>>> +++ b/include/linux/pci-acpi.h
>>>>>> @@ -25,6 +25,7 @@ static inline acpi_status
>>>>>> pci_acpi_remove_pm_notifier(struct acpi_device *dev)
>>>>>>    extern phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle
>>>>>> handle);
>>>>>>
>>>>>>    extern phys_addr_t pci_mcfg_lookup(u16 domain, struct resource
>>>>>> *bus_res);
>>>>>> +extern struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root
>>>>>> *root);
>>>>>>
>>>>>>    static inline acpi_handle acpi_find_root_bridge_handle(struct
>>>>>> pci_dev
>>>>>> *pdev)
>>>>>>    {
>>>>>> @@ -72,6 +73,25 @@ struct acpi_pci_root_ops {
>>>>>>         int (*prepare_resources)(struct acpi_pci_root_info *info);
>>>>>>    };
>>>>>>
>>>>>> +struct pci_cfg_fixup {
>>>>>> +     struct pci_ecam_ops *ops;
>>>>>> +     char *oem_id;
>>>>>> +     char *oem_table_id;
>>>>>> +     int domain;
>>>>>> +     int bus_num;
>>>>>> +};
>>>>>> +
>>>>>> +#define PCI_MCFG_DOMAIN_ANY  -1
>>>>>> +#define PCI_MCFG_BUS_ANY     -1
>>>>>> +
>>>>>> +/* Designate a routine to fix up buggy MCFG */
>>>>>> +#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, dom,
>>>>>> bus) \
>>>>>> +     static const struct
>>>>>> pci_cfg_fixup                               \
>>>>>> +
>>>>>> __mcfg_fixup_##oem_id##oem_table_id##dom##bus                   \
>>>>>
>>>>>
>>>>> I'm not entirely sure that this is the right fix--I'm pretty blindly
>>>>> following a GCC documentation suggestion [1]--but removing the
>>>>> first two
>>>>> preprocessor concatenation operators "##" solved the following build
>>>>> error
>>>>> for me.
>>>>>
>>>>> include/linux/pci-acpi.h:90:2: error: pasting "__mcfg_fixup_" and
>>>>> ""QCOM"" does not give a valid preprocessing token
>>>>>     __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>>>>
>>>>
>>>> I think the problem is gcc is not happy with quoted string when
>>>> processing these tokens
>>>> (""QCOM"", the extra "" are added by gcc). So should we not concat
>>>> string tokens and
>>>> use the fixup definition in v1 of this RFC:
>>>> /* Designate a routine to fix up buggy MCFG */
>>>> #define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, rev, dom,
>>>> bus)             \
>>>>           static const struct pci_cfg_fixup
>>>> __mcfg_fixup_##system##dom##bus\
>>>>            __used
>>>> __attribute__((__section__(".acpi_fixup_mcfg"),         \
>>>>                                   aligned((sizeof(void *)))))
>>>> =           \
>>>>           { ops, oem_id, rev, dom, bus };
>>>
>>>
>>> V1 fixup exist the redefinition error when compiling mutiple
>>> DECLARE_ACPI_MCFG_FIXUP
>>> with the same PCI_MCFG_DOMAIN_ANY and PCI_MCFG_BUS_ANY.
>>>
>>> #define EFI_ACPI_HISI_OEM_ID "HISI"
>>> #define EFI_ACPI_HISI_D02_OEM_TABLE_ID "HISI-D02"
>>> #define EFI_ACPI_HISI_D03_OEM_TABLE_ID "HISI-D03"
>>>
>>> DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
>>>         EFI_ACPI_HISI_D02_OEM_TABLE_ID, PCI_MCFG_DOMAIN_ANY,
>>> PCI_MCFG_BUS_ANY);
>>>
>>> DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
>>>         EFI_ACPI_HISI_D03_OEM_TABLE_ID, PCI_MCFG_DOMAIN_ANY,
>>> PCI_MCFG_BUS_ANY);
>>>
>>> In file included from drivers/pci/host/pcie-hisi-acpi.c:15:0:
>>> include/linux/pci-acpi.h:98:43: error: redefinition of
>>> '__mcfg_fixup_systemPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY'
>>>           static const struct pci_cfg_fixup
>>> __mcfg_fixup_##system##dom##bus\
>>>                                             ^
>>> drivers/pci/host/pcie-hisi-acpi.c:215:1: note: in expansion of macro
>>> 'DECLARE_ACPI_MCFG_FIXUP'
>>>   DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
>>>   ^
>>> include/linux/pci-acpi.h:98:43: note: previous definition of
>>> '__mcfg_fixup_systemPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY' was here
>>>           static const struct pci_cfg_fixup
>>> __mcfg_fixup_##system##dom##bus\
>>>                                             ^
>>> drivers/pci/host/pcie-hisi-acpi.c:212:1: note: in expansion of macro
>>> 'DECLARE_ACPI_MCFG_FIXUP'
>>>
>>>
>>> V2 fixup can resolve the redefinition error, but need to use macro.
>>> We can see that the name of macro is not replace with it's value in
>>> "__mcfg_fixup_EFI_ACPI_HISI_OEM_IDEFI_ACPI_HISI_D03_OEM_TABLE_IDPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY".
>>>
>>>
>>> Any good idea is appreciated.
>> Hmmm.
>>
>> I was testing # op and using min_t to get the min-len when doing
>> strncmp similar to Chris' suggestion (using min_t avoids type
>> warnings)
>>
>> /* Designate a routine to fix up buggy MCFG */
>> #define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, rev, dom,
>> bus) \
>>          static const struct pci_cfg_fixup
>> __mcfg_fixup##oem_id##oem_table_id##rev##dom##bus\
>>           __used
>> __attribute__((__section__(".acpi_fixup_mcfg"),         \
>>                                  aligned((sizeof(void *)))))
>> =           \
>
>>          { ops, #oem_id, #oem_table_id, rev, dom, bus };
>
>
> This should change to { ops, oem_id, oem_table_id, rev, dom, bus };
> ‘#’ is not need.

Both solutions are OK.

1. This works when we use macros as OEM ID and OEM table ID:

#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, rev, dom, bus)\
	static const struct pci_cfg_fixup				\
		__mcfg_fixup_##oem_id##oem_table_id##dom##bus		\
	 __used	__attribute__((__section__(".acpi_fixup_mcfg"),		\
				aligned((sizeof(void *))))) =		\
	{ ops, oem_id, oem_table_id, rev, dom, bus };

#define OEM_ID "XXXXXX"
#define OEM_TABLE_ID "YYYYYYYY"

DECLARE_ACPI_MCFG_FIXUP(&quirk_ops, OEM_ID, OEM_TABLE_ID, 1, 
PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);

2. This works w/o macro which means we need to define OEM ID and OEM as 
string w/o quotation marks:

#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, rev, dom, bus)\
static const struct pci_cfg_fixup \
__mcfg_fixup_##oem_id##oem_table_id##dom##bus \
__used __attribute__((__section__(".acpi_fixup_mcfg"), \
aligned((sizeof(void *))))) = \
{ ops, #oem_id, #oem_table_id, rev, dom, bus };

DECLARE_ACPI_MCFG_FIXUP(&quirk_ops, XXXXXX, YYYYYYYY, 1, 
PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);

Personally I think that (2) is better, no need for macro definitions.
Tomasz

Duc Dang June 14, 2016, 5:43 p.m. UTC | #13

On Tue, Jun 14, 2016 at 4:52 AM, Tomasz Nowicki <[e-mail]> wrote:
> On 14.06.2016 11:45, Dongdong Liu wrote:
>>
>> Hi Duc
>>
>> 在 2016/6/14 17:00, Duc Dang 写道:
>>>
>>> On Mon, Jun 13, 2016 at 10:51 PM, Dongdong Liu
>>> <[e-mail]> wrote:
>>>>
>>>> Hi Duc
>>>>
>>>> 在 2016/6/14 4:57, Duc Dang 写道:
>>>>>
>>>>>
>>>>> On Mon, Jun 13, 2016 at 8:47 AM, Christopher Covington
>>>>> <[e-mail]> wrote:
>>>>>>
>>>>>>
>>>>>> Hi Dongdong,
>>>>>>
>>>>>> On 06/13/2016 09:02 AM, Dongdong Liu wrote:
>>>>>>>
>>>>>>>
>>>>>>> diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
>>>>>>> index d3c3e85..49612b3 100644
>>>>>>> --- a/drivers/acpi/pci_mcfg.c
>>>>>>> +++ b/drivers/acpi/pci_mcfg.c
>>>>>>> @@ -22,6 +22,10 @@
>>>>>>>    #include <linux/kernel.h>
>>>>>>>    #include <linux/pci.h>
>>>>>>>    #include <linux/pci-acpi.h>
>>>>>>> +#include <linux/pci-ecam.h>
>>>>>>> +
>>>>>>> +/* Root pointer to the mapped MCFG table */
>>>>>>> +static struct acpi_table_mcfg *mcfg_table;
>>>>>>>
>>>>>>>    /* Structure to hold entries from the MCFG table */
>>>>>>>    struct mcfg_entry {
>>>>>>> @@ -35,6 +39,38 @@ struct mcfg_entry {
>>>>>>>    /* List to save mcfg entries */
>>>>>>>    static LIST_HEAD(pci_mcfg_list);
>>>>>>>
>>>>>>> +extern struct pci_cfg_fixup __start_acpi_mcfg_fixups[];
>>>>>>> +extern struct pci_cfg_fixup __end_acpi_mcfg_fixups[];
>>>>>>> +
>>>>>>> +struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root)
>>>>>>> +{
>>>>>>> +     int bus_num = root->secondary.start;
>>>>>>> +     int domain = root->segment;
>>>>>>> +     struct pci_cfg_fixup *f;
>>>>>>> +
>>>>>>> +     if (!mcfg_table)
>>>>>>> +             return &pci_generic_ecam_ops;
>>>>>>> +
>>>>>>> +     /*
>>>>>>> +      * Match against platform specific quirks and return
>>>>>>> corresponding
>>>>>>> +      * CAM ops.
>>>>>>> +      *
>>>>>>> +      * First match against PCI topology <domain:bus> then use
>>>>>>> OEM ID
>>>>>>> and
>>>>>>> +      * OEM revision from MCFG table standard header.
>>>>>>> +      */
>>>>>>> +     for (f = __start_acpi_mcfg_fixups; f < __end_acpi_mcfg_fixups;
>>>>>>> f++) {
>>>>>>> +             if ((f->domain == domain || f->domain ==
>>>>>>> PCI_MCFG_DOMAIN_ANY) &&
>>>>>>> +                 (f->bus_num == bus_num || f->bus_num ==
>>>>>>> PCI_MCFG_BUS_ANY) &&
>>>>>>> +                 (!strncmp(f->oem_id, mcfg_table->header.oem_id,
>>>>>>> +                           ACPI_OEM_ID_SIZE)) &&
>>>>>>> +                 (!strncmp(f->oem_table_id,
>>>>>>> mcfg_table->header.oem_table_id,
>>>>>>> +                           ACPI_OEM_TABLE_ID_SIZE)))
>>>>>>
>>>>>>
>>>>>>
>>>>>> This would just be a small convenience, but if the character count
>>>>>> used
>>>>>> here were
>>>>>>
>>>>>> min(strlen(f->oem_id), ACPI_OEM_ID_SIZE)
>>>>>>
>>>>>> then the parameters to DECLARE_ACPI_MCFG_FIXUP macro could be
>>>>>> substrings
>>>>>> and
>>>>>> wouldn't need to be padded out to the full length.
>>>>>>
>>>>>>> +                     return f->ops;
>>>>>>> +     }
>>>>>>> +     /* No quirks, use ECAM */
>>>>>>> +     return &pci_generic_ecam_ops;
>>>>>>> +}
>>>>>>
>>>>>>
>>>>>>
>>>>>>> diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
>>>>>>> index 7d63a66..088a1da 100644
>>>>>>> --- a/include/linux/pci-acpi.h
>>>>>>> +++ b/include/linux/pci-acpi.h
>>>>>>> @@ -25,6 +25,7 @@ static inline acpi_status
>>>>>>> pci_acpi_remove_pm_notifier(struct acpi_device *dev)
>>>>>>>    extern phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle
>>>>>>> handle);
>>>>>>>
>>>>>>>    extern phys_addr_t pci_mcfg_lookup(u16 domain, struct resource
>>>>>>> *bus_res);
>>>>>>> +extern struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root
>>>>>>> *root);
>>>>>>>
>>>>>>>    static inline acpi_handle acpi_find_root_bridge_handle(struct
>>>>>>> pci_dev
>>>>>>> *pdev)
>>>>>>>    {
>>>>>>> @@ -72,6 +73,25 @@ struct acpi_pci_root_ops {
>>>>>>>         int (*prepare_resources)(struct acpi_pci_root_info *info);
>>>>>>>    };
>>>>>>>
>>>>>>> +struct pci_cfg_fixup {
>>>>>>> +     struct pci_ecam_ops *ops;
>>>>>>> +     char *oem_id;
>>>>>>> +     char *oem_table_id;
>>>>>>> +     int domain;
>>>>>>> +     int bus_num;
>>>>>>> +};
>>>>>>> +
>>>>>>> +#define PCI_MCFG_DOMAIN_ANY  -1
>>>>>>> +#define PCI_MCFG_BUS_ANY     -1
>>>>>>> +
>>>>>>> +/* Designate a routine to fix up buggy MCFG */
>>>>>>> +#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, dom,
>>>>>>> bus) \
>>>>>>> +     static const struct
>>>>>>> pci_cfg_fixup                               \
>>>>>>> +
>>>>>>> __mcfg_fixup_##oem_id##oem_table_id##dom##bus                   \
>>>>>>
>>>>>>
>>>>>>
>>>>>> I'm not entirely sure that this is the right fix--I'm pretty blindly
>>>>>> following a GCC documentation suggestion [1]--but removing the
>>>>>> first two
>>>>>> preprocessor concatenation operators "##" solved the following build
>>>>>> error
>>>>>> for me.
>>>>>>
>>>>>> include/linux/pci-acpi.h:90:2: error: pasting "__mcfg_fixup_" and
>>>>>> ""QCOM"" does not give a valid preprocessing token
>>>>>>     __mcfg_fixup_##oem_id##oem_table_id##dom##bus   \
>>>>>
>>>>>
>>>>>
>>>>> I think the problem is gcc is not happy with quoted string when
>>>>> processing these tokens
>>>>> (""QCOM"", the extra "" are added by gcc). So should we not concat
>>>>> string tokens and
>>>>> use the fixup definition in v1 of this RFC:
>>>>> /* Designate a routine to fix up buggy MCFG */
>>>>> #define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, rev, dom,
>>>>> bus)             \
>>>>>           static const struct pci_cfg_fixup
>>>>> __mcfg_fixup_##system##dom##bus\
>>>>>            __used
>>>>> __attribute__((__section__(".acpi_fixup_mcfg"),         \
>>>>>                                   aligned((sizeof(void *)))))
>>>>> =           \
>>>>>           { ops, oem_id, rev, dom, bus };
>>>>
>>>>
>>>>
>>>> V1 fixup exist the redefinition error when compiling mutiple
>>>> DECLARE_ACPI_MCFG_FIXUP
>>>> with the same PCI_MCFG_DOMAIN_ANY and PCI_MCFG_BUS_ANY.
>>>>
>>>> #define EFI_ACPI_HISI_OEM_ID "HISI"
>>>> #define EFI_ACPI_HISI_D02_OEM_TABLE_ID "HISI-D02"
>>>> #define EFI_ACPI_HISI_D03_OEM_TABLE_ID "HISI-D03"
>>>>
>>>> DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
>>>>         EFI_ACPI_HISI_D02_OEM_TABLE_ID, PCI_MCFG_DOMAIN_ANY,
>>>> PCI_MCFG_BUS_ANY);
>>>>
>>>> DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
>>>>         EFI_ACPI_HISI_D03_OEM_TABLE_ID, PCI_MCFG_DOMAIN_ANY,
>>>> PCI_MCFG_BUS_ANY);
>>>>
>>>> In file included from drivers/pci/host/pcie-hisi-acpi.c:15:0:
>>>> include/linux/pci-acpi.h:98:43: error: redefinition of
>>>> '__mcfg_fixup_systemPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY'
>>>>           static const struct pci_cfg_fixup
>>>> __mcfg_fixup_##system##dom##bus\
>>>>                                             ^
>>>> drivers/pci/host/pcie-hisi-acpi.c:215:1: note: in expansion of macro
>>>> 'DECLARE_ACPI_MCFG_FIXUP'
>>>>   DECLARE_ACPI_MCFG_FIXUP(&hisi_pcie_ecam_ops, EFI_ACPI_HISI_OEM_ID,
>>>>   ^
>>>> include/linux/pci-acpi.h:98:43: note: previous definition of
>>>> '__mcfg_fixup_systemPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY' was here
>>>>           static const struct pci_cfg_fixup
>>>> __mcfg_fixup_##system##dom##bus\
>>>>                                             ^
>>>> drivers/pci/host/pcie-hisi-acpi.c:212:1: note: in expansion of macro
>>>> 'DECLARE_ACPI_MCFG_FIXUP'
>>>>
>>>>
>>>> V2 fixup can resolve the redefinition error, but need to use macro.
>>>> We can see that the name of macro is not replace with it's value in
>>>>
>>>> "__mcfg_fixup_EFI_ACPI_HISI_OEM_IDEFI_ACPI_HISI_D03_OEM_TABLE_IDPCI_MCFG_DOMAIN_ANYPCI_MCFG_BUS_ANY".
>>>>
>>>>
>>>> Any good idea is appreciated.
>>>
>>> Hmmm.
>>>
>>> I was testing # op and using min_t to get the min-len when doing
>>> strncmp similar to Chris' suggestion (using min_t avoids type
>>> warnings)
>>>
>>> /* Designate a routine to fix up buggy MCFG */
>>> #define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, rev, dom,
>>> bus) \
>>>          static const struct pci_cfg_fixup
>>> __mcfg_fixup##oem_id##oem_table_id##rev##dom##bus\
>>>           __used
>>> __attribute__((__section__(".acpi_fixup_mcfg"),         \
>>>                                  aligned((sizeof(void *)))))
>>> =           \
>>
>>
>>>          { ops, #oem_id, #oem_table_id, rev, dom, bus };
>>
>>
>>
>> This should change to { ops, oem_id, oem_table_id, rev, dom, bus };
>> ‘#’ is not need.
>
>
> Both solutions are OK.
>
> 1. This works when we use macros as OEM ID and OEM table ID:
>
> #define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, rev, dom, bus)\
>         static const struct pci_cfg_fixup                               \
>                 __mcfg_fixup_##oem_id##oem_table_id##dom##bus           \
>          __used __attribute__((__section__(".acpi_fixup_mcfg"),         \
>                                 aligned((sizeof(void *))))) =           \
>         { ops, oem_id, oem_table_id, rev, dom, bus };
>
> #define OEM_ID "XXXXXX"
> #define OEM_TABLE_ID "YYYYYYYY"
>
> DECLARE_ACPI_MCFG_FIXUP(&quirk_ops, OEM_ID, OEM_TABLE_ID, 1,
> PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);
>
> 2. This works w/o macro which means we need to define OEM ID and OEM as
> string w/o quotation marks:
>
> #define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, rev, dom, bus)\
> static const struct pci_cfg_fixup \
> __mcfg_fixup_##oem_id##oem_table_id##dom##bus \
> __used __attribute__((__section__(".acpi_fixup_mcfg"), \
> aligned((sizeof(void *))))) = \
> { ops, #oem_id, #oem_table_id, rev, dom, bus };
>
> DECLARE_ACPI_MCFG_FIXUP(&quirk_ops, XXXXXX, YYYYYYYY, 1,
> PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY);

In case of oem_id and oem_table_id have special characters ("HISI-D02"
as an example), #2 will have problem unless we use macro definitions
for them.

>
> Personally I think that (2) is better, no need for macro definitions.
> Tomasz
Regards,
Duc Dang

Jon Masters June 16, 2016, 6:31 a.m. UTC | #14

On 06/13/2016 09:54 AM, Gabriele Paoloni wrote:
> Hi Tomasz, Jon

Hi Gab,

Sorry for the lag in following up.

<snip>

> As you can see here Liudongdong has replaced oem_revision with
> oem_table_id.
> 
> Now it seems that there are some platforms that have already shipped
> using a matching based on the oem_revision (right Jon?)

Actually, it turns out (Cov is correct) that we can just match on OEM
Table ID. The revision should not generally be needed and the vendors
will just need to make sure that they change OEM Table ID in future
silicon. An example from two shipping platforms:

1). AppliedMicro Mustang:

[000h 0000   4]                    Signature : "MCFG"    [Memory Mapped
Configuration table]
[004h 0004   4]                 Table Length : 0000003C
[008h 0008   1]                     Revision : 01
[009h 0009   1]                     Checksum : 4A
[00Ah 0010   6]                       Oem ID : "APM   "
[010h 0016   8]                 Oem Table ID : "XGENE   "
[018h 0024   4]                 Oem Revision : 00000002
[01Ch 0028   4]              Asl Compiler ID : "INTL"
[020h 0032   4]        Asl Compiler Revision : 20140724

2). HP(E[0]) Moonshot:

[000h 0000   4]                    Signature : "MCFG"    [Memory Mapped
Configuration table]
[004h 0004   4]                 Table Length : 0000003C
[008h 0008   1]                     Revision : 01
[009h 0009   1]                     Checksum : 48
[00Ah 0010   6]                       Oem ID : "APM   "
[010h 0016   8]                 Oem Table ID : "XGENE   "
[018h 0024   4]                 Oem Revision : 00000001
[01Ch 0028   4]              Asl Compiler ID : "HP  "
[020h 0032   4]        Asl Compiler Revision : 00000001

I have pinged the semiconductor (Applied) and insisted upon a written
plan (which I have now) for handling the first affect generation(s) and
future chip roadmap stuff, along with how they plan to upstream this
immediately as part of this thread. I have also done similar with each
of the other vendors (this is something ARM or Linaro should be doing).
But I particularly care about X-Gene because I want it to be loved as
shipping silicon in production systems (Moonshot) that are sitting and
waiting in the Fedora Phoenix datacenter in large quantity to come
online if only an upstream kernel would actually boot on them :)

> However I guess that if in FW they have defined oem_table_id properly
> they should be able to use this mechanism without needing to a FW update.

Correct.

> Can these vendors confirm this?

I've checked all current shipping silicon and prototypes.

> Tomasz do you think this can work for Cavium Thunder?

Will let the vendors followup directly as well.

Jon.

[0] Fortunately that name change doesn't factor when using semiconductor
matching...hopefully none of the non-complaint IP companies in gen1
stuff get bought and change their table names. In the unlikely event
that that does happen, I will preemptively beat them up and ensure that
something crazy doesn't happen with table contents.

Duc Dang June 16, 2016, 7:45 a.m. UTC | #15

On Wed, Jun 15, 2016 at 11:31 PM, Jon Masters <[e-mail]> wrote:
> On 06/13/2016 09:54 AM, Gabriele Paoloni wrote:
>> Hi Tomasz, Jon
>
> Hi Gab,
>
> Sorry for the lag in following up.
>
> <snip>
>
>> As you can see here Liudongdong has replaced oem_revision with
>> oem_table_id.
>>
>> Now it seems that there are some platforms that have already shipped
>> using a matching based on the oem_revision (right Jon?)
>
> Actually, it turns out (Cov is correct) that we can just match on OEM
> Table ID. The revision should not generally be needed and the vendors
> will just need to make sure that they change OEM Table ID in future
> silicon. An example from two shipping platforms:
>
> 1). AppliedMicro Mustang:
>
> [000h 0000   4]                    Signature : "MCFG"    [Memory Mapped
> Configuration table]
> [004h 0004   4]                 Table Length : 0000003C
> [008h 0008   1]                     Revision : 01
> [009h 0009   1]                     Checksum : 4A
> [00Ah 0010   6]                       Oem ID : "APM   "
> [010h 0016   8]                 Oem Table ID : "XGENE   "
> [018h 0024   4]                 Oem Revision : 00000002
> [01Ch 0028   4]              Asl Compiler ID : "INTL"
> [020h 0032   4]        Asl Compiler Revision : 20140724
>
> 2). HP(E[0]) Moonshot:
>
> [000h 0000   4]                    Signature : "MCFG"    [Memory Mapped
> Configuration table]
> [004h 0004   4]                 Table Length : 0000003C
> [008h 0008   1]                     Revision : 01
> [009h 0009   1]                     Checksum : 48
> [00Ah 0010   6]                       Oem ID : "APM   "
> [010h 0016   8]                 Oem Table ID : "XGENE   "
> [018h 0024   4]                 Oem Revision : 00000001
> [01Ch 0028   4]              Asl Compiler ID : "HP  "
> [020h 0032   4]        Asl Compiler Revision : 00000001
>
> I have pinged the semiconductor (Applied) and insisted upon a written
> plan (which I have now) for handling the first affect generation(s) and
> future chip roadmap stuff, along with how they plan to upstream this
> immediately as part of this thread. I have also done similar with each
> of the other vendors (this is something ARM or Linaro should be doing).
> But I particularly care about X-Gene because I want it to be loved as
> shipping silicon in production systems (Moonshot) that are sitting and
> waiting in the Fedora Phoenix datacenter in large quantity to come
> online if only an upstream kernel would actually boot on them :)

Thanks for the MCFG information on Moonshot system, Jon.

I will make sure the posted quirk for X-Gene takes care for HPE
Moonshot system as well.

Regards,
Duc Dang.

>
>> However I guess that if in FW they have defined oem_table_id properly
>> they should be able to use this mechanism without needing to a FW update.
>
> Correct.
>
>> Can these vendors confirm this?
>
> I've checked all current shipping silicon and prototypes.
>
>> Tomasz do you think this can work for Cavium Thunder?
>
> Will let the vendors followup directly as well.
>
> Jon.
>
> [0] Fortunately that name change doesn't factor when using semiconductor
> matching...hopefully none of the non-complaint IP companies in gen1
> stuff get bought and change their table names. In the unlikely event
> that that does happen, I will preemptively beat them up and ensure that
> something crazy doesn't happen with table contents.
>
> --
> Computer Architect | Sent from my Fedora powered laptop

Jon Masters June 16, 2016, 7:54 a.m. UTC | #16

:) We should be good with a match on XGENE (but be careful with substring matching) as long as future platforms change that to eg XGENE3 (which is a publicly announced future chip). What you want to avoid is a shorter match later triggering on a future generation.

There are a lot of folks eagerly awaiting Moonshot running an upstream kernel in F25, both for 64 and 32-bit (VMs running 32-bit can replace older builders). I can picture a wonderful world in which this whole ARM server ecosystem works properly with folks doing what they should have three years ago and development happening on upstream kernels with ACPI. Then things become incredibly dull just like x86 - do the dev against upstream, pull into an enterprise distro after it is tested out in a Fedora cycle...and no random nonsense patches. Next thing we know there will be media reports covering silicon that won't end with a rant about how they couldn't get the right firmware and hacked up Ubuntu kernel booting.

Best, and goodnight :)

Jon.

Patch

diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
index d3c3e85..49612b3 100644
--- a/drivers/acpi/pci_mcfg.c
+++ b/drivers/acpi/pci_mcfg.c
@@ -22,6 +22,10 @@ 
 #include <linux/kernel.h>
 #include <linux/pci.h>
 #include <linux/pci-acpi.h>
+#include <linux/pci-ecam.h>
+
+/* Root pointer to the mapped MCFG table */
+static struct acpi_table_mcfg *mcfg_table;
 
 /* Structure to hold entries from the MCFG table */
 struct mcfg_entry {
@@ -35,6 +39,38 @@  struct mcfg_entry {
 /* List to save mcfg entries */
 static LIST_HEAD(pci_mcfg_list);
 
+extern struct pci_cfg_fixup __start_acpi_mcfg_fixups[];
+extern struct pci_cfg_fixup __end_acpi_mcfg_fixups[];
+
+struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root)
+{
+	int bus_num = root->secondary.start;
+	int domain = root->segment;
+	struct pci_cfg_fixup *f;
+
+	if (!mcfg_table)
+		return &pci_generic_ecam_ops;
+
+	/*
+	 * Match against platform specific quirks and return corresponding
+	 * CAM ops.
+	 *
+	 * First match against PCI topology <domain:bus> then use OEM ID and
+	 * OEM revision from MCFG table standard header.
+	 */
+	for (f = __start_acpi_mcfg_fixups; f < __end_acpi_mcfg_fixups; f++) {
+		if ((f->domain == domain || f->domain == PCI_MCFG_DOMAIN_ANY) &&
+		    (f->bus_num == bus_num || f->bus_num == PCI_MCFG_BUS_ANY) &&
+		    (!strncmp(f->oem_id, mcfg_table->header.oem_id,
+			      ACPI_OEM_ID_SIZE)) &&
+		    (!strncmp(f->oem_table_id, mcfg_table->header.oem_table_id,
+			      ACPI_OEM_TABLE_ID_SIZE)))
+			return f->ops;
+	}
+	/* No quirks, use ECAM */
+	return &pci_generic_ecam_ops;
+}
+
 phys_addr_t pci_mcfg_lookup(u16 seg, struct resource *bus_res)
 {
 	struct mcfg_entry *e;
@@ -54,7 +90,6 @@  phys_addr_t pci_mcfg_lookup(u16 seg, struct resource *bus_res)
 
 static __init int pci_mcfg_parse(struct acpi_table_header *header)
 {
-	struct acpi_table_mcfg *mcfg;
 	struct acpi_mcfg_allocation *mptr;
 	struct mcfg_entry *e, *arr;
 	int i, n;
@@ -64,8 +99,8 @@  static __init int pci_mcfg_parse(struct acpi_table_header *header)
 
 	n = (header->length - sizeof(struct acpi_table_mcfg)) /
 					sizeof(struct acpi_mcfg_allocation);
-	mcfg = (struct acpi_table_mcfg *)header;
-	mptr = (struct acpi_mcfg_allocation *) &mcfg[1];
+	mcfg_table = (struct acpi_table_mcfg *)header;
+	mptr = (struct acpi_mcfg_allocation *) &mcfg_table[1];
 
 	arr = kcalloc(n, sizeof(*arr), GFP_KERNEL);
 	if (!arr)
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 6a67ab9..43604fc 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -300,6 +300,13 @@ 
 		VMLINUX_SYMBOL(__end_pci_fixups_suspend_late) = .;	\
 	}								\
 									\
+	/* ACPI MCFG quirks */						\
+	.acpi_fixup        : AT(ADDR(.acpi_fixup) - LOAD_OFFSET) {	\
+		VMLINUX_SYMBOL(__start_acpi_mcfg_fixups) = .;		\
+		*(.acpi_fixup_mcfg)					\
+		VMLINUX_SYMBOL(__end_acpi_mcfg_fixups) = .;		\
+	}								\
+									\
 	/* Built-in firmware blobs */					\
 	.builtin_fw        : AT(ADDR(.builtin_fw) - LOAD_OFFSET) {	\
 		VMLINUX_SYMBOL(__start_builtin_fw) = .;			\
diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
index 7d63a66..088a1da 100644
--- a/include/linux/pci-acpi.h
+++ b/include/linux/pci-acpi.h
@@ -25,6 +25,7 @@  static inline acpi_status pci_acpi_remove_pm_notifier(struct acpi_device *dev)
 extern phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle);
 
 extern phys_addr_t pci_mcfg_lookup(u16 domain, struct resource *bus_res);
+extern struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root);
 
 static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev)
 {
@@ -72,6 +73,25 @@  struct acpi_pci_root_ops {
 	int (*prepare_resources)(struct acpi_pci_root_info *info);
 };
 
+struct pci_cfg_fixup {
+	struct pci_ecam_ops *ops;
+	char *oem_id;
+	char *oem_table_id;
+	int domain;
+	int bus_num;
+};
+
+#define PCI_MCFG_DOMAIN_ANY	-1
+#define PCI_MCFG_BUS_ANY	-1
+
+/* Designate a routine to fix up buggy MCFG */
+#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, dom, bus)	\
+	static const struct pci_cfg_fixup				\
+	__mcfg_fixup_##oem_id##oem_table_id##dom##bus			\
+	__used	__attribute__((__section__(".acpi_fixup_mcfg"),		\
+				aligned((sizeof(void *))))) =		\
+	{ ops, oem_id, oem_table_id, dom, bus };
+
 extern int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info);
 extern struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
 					    struct acpi_pci_root_ops *ops,