diff mbox

[V4,3/6] pci: Generic function for setting up PCI device DMA coherency

Message ID 1431724994-21601-4-git-send-email-Suravee.Suthikulpanit@amd.com (mailing list archive)
State New, archived
Headers show

Commit Message

Suravee Suthikulpanit May 15, 2015, 9:23 p.m. UTC
This patch refactors of_pci_dma_configure() into a more generic
pci_dma_configure(), which can be reused by non-OF code.
Then, it adds support for setting up PCI device DMA coherency from
ACPI _CCA object that should normally be specified in the DSDT node
of its PCI host bridge..

Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Rob Herring <robh+dt@kernel.org>
CC: Will Deacon <will.deacon@arm.com>
CC: Rafael J. Wysocki <rjw@rjwysocki.net>
CC: Murali Karicheri <m-karicheri2@ti.com>
---
 drivers/of/of_pci.c    | 20 --------------------
 drivers/pci/probe.c    | 35 +++++++++++++++++++++++++++++++++--
 include/linux/of_pci.h |  3 ---
 3 files changed, 33 insertions(+), 25 deletions(-)

Comments

Rafael J. Wysocki May 15, 2015, 11:59 p.m. UTC | #1
On Friday, May 15, 2015 04:23:11 PM Suravee Suthikulpanit wrote:
> This patch refactors of_pci_dma_configure() into a more generic
> pci_dma_configure(), which can be reused by non-OF code.
> Then, it adds support for setting up PCI device DMA coherency from
> ACPI _CCA object that should normally be specified in the DSDT node
> of its PCI host bridge..
> 
> Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
> CC: Bjorn Helgaas <bhelgaas@google.com>
> CC: Catalin Marinas <catalin.marinas@arm.com>
> CC: Rob Herring <robh+dt@kernel.org>
> CC: Will Deacon <will.deacon@arm.com>
> CC: Rafael J. Wysocki <rjw@rjwysocki.net>
> CC: Murali Karicheri <m-karicheri2@ti.com>
> ---
>  drivers/of/of_pci.c    | 20 --------------------
>  drivers/pci/probe.c    | 35 +++++++++++++++++++++++++++++++++--
>  include/linux/of_pci.h |  3 ---
>  3 files changed, 33 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
> index 5751dc5..b66ee4e 100644
> --- a/drivers/of/of_pci.c
> +++ b/drivers/of/of_pci.c
> @@ -117,26 +117,6 @@ int of_get_pci_domain_nr(struct device_node *node)
>  }
>  EXPORT_SYMBOL_GPL(of_get_pci_domain_nr);
>  
> -/**
> - * of_pci_dma_configure - Setup DMA configuration
> - * @dev: ptr to pci_dev struct of the PCI device
> - *
> - * Function to update PCI devices's DMA configuration using the same
> - * info from the OF node of host bridge's parent (if any).
> - */
> -void of_pci_dma_configure(struct pci_dev *pci_dev)
> -{
> -	struct device *dev = &pci_dev->dev;
> -	struct device *bridge = pci_get_host_bridge_device(pci_dev);
> -
> -	if (!bridge->parent)
> -		return;
> -
> -	of_dma_configure(dev, bridge->parent->of_node);
> -	pci_put_host_bridge_device(bridge);
> -}
> -EXPORT_SYMBOL_GPL(of_pci_dma_configure);
> -
>  #if defined(CONFIG_OF_ADDRESS)
>  /**
>   * of_pci_get_host_bridge_resources - Parse PCI host bridge resources from DT
> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
> index 6675a7a..3c6f2e5 100644
> --- a/drivers/pci/probe.c
> +++ b/drivers/pci/probe.c
> @@ -6,12 +6,14 @@
>  #include <linux/delay.h>
>  #include <linux/init.h>
>  #include <linux/pci.h>
> -#include <linux/of_pci.h>
> +#include <linux/of_device.h>
>  #include <linux/pci_hotplug.h>
>  #include <linux/slab.h>
>  #include <linux/module.h>
>  #include <linux/cpumask.h>
>  #include <linux/pci-aspm.h>
> +#include <linux/acpi.h>
> +#include <linux/property.h>
>  #include <asm-generic/pci-bridge.h>
>  #include "pci.h"
>  
> @@ -1508,6 +1510,35 @@ static void pci_init_capabilities(struct pci_dev *dev)
>  	pci_enable_acs(dev);
>  }
>  
> +/**
> + * pci_dma_configure - Setup DMA configuration
> + * @pci_dev: ptr to pci_dev struct of the PCI device
> + *
> + * Function to update PCI devices's DMA configuration using the same
> + * info from the OF node or ACPI node of host bridge's parent (if any).
> + */
> +static void pci_dma_configure(struct pci_dev *pci_dev)
> +{
> +	struct device *dev = &pci_dev->dev;
> +	struct device *bridge = pci_get_host_bridge_device(pci_dev);
> +	struct device *host = bridge->parent;
> +	struct acpi_device *adev;
> +
> +	if (!host)
> +		return;
> +
> +	if (acpi_disabled) {
> +		of_dma_configure(dev, host->of_node);

I'd rather do

	if (IS_ENABLED(CONFIG_OF) && host->of_node) {
		of_dma_configure(dev, host->of_node);
	} else {
		struct acpi_device *adev = ACPI_COMPANION(host);

		if (adev && acpi_dma_is_supported(adev)) {


> +	} else if (has_acpi_companion(host)) {
> +		adev = acpi_node(host->fwnode);
> +		if (acpi_dma_is_supported(adev))
> +			arch_setup_dma_ops(dev, 0, 0, NULL,
> +					   acpi_dma_is_coherent(adev));
> +	}
> +
> +	pci_put_host_bridge_device(bridge);
> +}
> +
>  void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
>  {
>  	int ret;
> @@ -1521,7 +1552,7 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
>  	dev->dev.dma_mask = &dev->dma_mask;
>  	dev->dev.dma_parms = &dev->dma_parms;
>  	dev->dev.coherent_dma_mask = 0xffffffffull;
> -	of_pci_dma_configure(dev);
> +	pci_dma_configure(dev);

Also I'm not quite sure if that's actually OK.

We should be handling the DMA setup on x86 in the ACPI case already without it.
Or is this a NOP on x86?

>  
>  	pci_set_dma_max_seg_size(dev, 65536);
>  	pci_set_dma_seg_boundary(dev, 0xffffffff);
> diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h
> index 29fd3fe..ce0e5ab 100644
> --- a/include/linux/of_pci.h
> +++ b/include/linux/of_pci.h
> @@ -16,7 +16,6 @@ int of_pci_get_devfn(struct device_node *np);
>  int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin);
>  int of_pci_parse_bus_range(struct device_node *node, struct resource *res);
>  int of_get_pci_domain_nr(struct device_node *node);
> -void of_pci_dma_configure(struct pci_dev *pci_dev);
>  #else
>  static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq)
>  {
> @@ -51,8 +50,6 @@ of_get_pci_domain_nr(struct device_node *node)
>  {
>  	return -1;
>  }
> -
> -static inline void of_pci_dma_configure(struct pci_dev *pci_dev) { }
>  #endif
>  
>  #if defined(CONFIG_OF_ADDRESS)
>
Bjorn Helgaas May 16, 2015, 12:41 p.m. UTC | #2
On Fri, May 15, 2015 at 4:23 PM, Suravee Suthikulpanit
<Suravee.Suthikulpanit@amd.com> wrote:
> This patch refactors of_pci_dma_configure() into a more generic
> pci_dma_configure(), which can be reused by non-OF code.
> Then, it adds support for setting up PCI device DMA coherency from
> ACPI _CCA object that should normally be specified in the DSDT node
> of its PCI host bridge..

From the changelog, it sounds like you might be able to split this
into two patches:

1) Refactor of_pci_dma_configure(), with no functional change
2) Add support for using _CCA

If that's possible, please do so to make this easier to review.

Bjorn
Suravee Suthikulpanit May 16, 2015, 3:12 p.m. UTC | #3
Hi Rafael,

On 5/15/15, 18:59, "Rafael J. Wysocki" <rjw@rjwysocki.net> wrote:

>On Friday, May 15, 2015 04:23:11 PM Suravee Suthikulpanit wrote:
>> This patch refactors of_pci_dma_configure() into a more generic
>> pci_dma_configure(), which can be reused by non-OF code.
>> Then, it adds support for setting up PCI device DMA coherency from
>> ACPI _CCA object that should normally be specified in the DSDT node
>> of its PCI host bridge..
>> 
>> Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
>> CC: Bjorn Helgaas <bhelgaas@google.com>
>> CC: Catalin Marinas <catalin.marinas@arm.com>
>> CC: Rob Herring <robh+dt@kernel.org>
>> CC: Will Deacon <will.deacon@arm.com>
>> CC: Rafael J. Wysocki <rjw@rjwysocki.net>
>> CC: Murali Karicheri <m-karicheri2@ti.com>
>> ---
>>  drivers/of/of_pci.c    | 20 --------------------
>>  drivers/pci/probe.c    | 35 +++++++++++++++++++++++++++++++++--
>>  include/linux/of_pci.h |  3 ---
>>  3 files changed, 33 insertions(+), 25 deletions(-)
>> 
>> diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
>> index 5751dc5..b66ee4e 100644
>> --- a/drivers/of/of_pci.c
>> +++ b/drivers/of/of_pci.c
>> @@ -117,26 +117,6 @@ int of_get_pci_domain_nr(struct device_node *node)
>>  }
>>  EXPORT_SYMBOL_GPL(of_get_pci_domain_nr);
>>  
>> -/**
>> - * of_pci_dma_configure - Setup DMA configuration
>> - * @dev: ptr to pci_dev struct of the PCI device
>> - *
>> - * Function to update PCI devices's DMA configuration using the same
>> - * info from the OF node of host bridge's parent (if any).
>> - */
>> -void of_pci_dma_configure(struct pci_dev *pci_dev)
>> -{
>> -	struct device *dev = &pci_dev->dev;
>> -	struct device *bridge = pci_get_host_bridge_device(pci_dev);
>> -
>> -	if (!bridge->parent)
>> -		return;
>> -
>> -	of_dma_configure(dev, bridge->parent->of_node);
>> -	pci_put_host_bridge_device(bridge);
>> -}
>> -EXPORT_SYMBOL_GPL(of_pci_dma_configure);
>> -
>>  #if defined(CONFIG_OF_ADDRESS)
>>  /**
>>   * of_pci_get_host_bridge_resources - Parse PCI host bridge resources
>>from DT
>> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
>> index 6675a7a..3c6f2e5 100644
>> --- a/drivers/pci/probe.c
>> +++ b/drivers/pci/probe.c
>> @@ -6,12 +6,14 @@
>>  #include <linux/delay.h>
>>  #include <linux/init.h>
>>  #include <linux/pci.h>
>> -#include <linux/of_pci.h>
>> +#include <linux/of_device.h>
>>  #include <linux/pci_hotplug.h>
>>  #include <linux/slab.h>
>>  #include <linux/module.h>
>>  #include <linux/cpumask.h>
>>  #include <linux/pci-aspm.h>
>> +#include <linux/acpi.h>
>> +#include <linux/property.h>
>>  #include <asm-generic/pci-bridge.h>
>>  #include "pci.h"
>>  
>> @@ -1508,6 +1510,35 @@ static void pci_init_capabilities(struct pci_dev
>>*dev)
>>  	pci_enable_acs(dev);
>>  }
>>  
>> +/**
>> + * pci_dma_configure - Setup DMA configuration
>> + * @pci_dev: ptr to pci_dev struct of the PCI device
>> + *
>> + * Function to update PCI devices's DMA configuration using the same
>> + * info from the OF node or ACPI node of host bridge's parent (if any).
>> + */
>> +static void pci_dma_configure(struct pci_dev *pci_dev)
>> +{
>> +	struct device *dev = &pci_dev->dev;
>> +	struct device *bridge = pci_get_host_bridge_device(pci_dev);
>> +	struct device *host = bridge->parent;
>> +	struct acpi_device *adev;
>> +
>> +	if (!host)
>> +		return;
>> +
>> +	if (acpi_disabled) {
>> +		of_dma_configure(dev, host->of_node);
>
>I'd rather do
>
>	if (IS_ENABLED(CONFIG_OF) && host->of_node) {
>		of_dma_configure(dev, host->of_node);
>	} else {
>		struct acpi_device *adev = ACPI_COMPANION(host);
>
>		if (adev && acpi_dma_is_supported(adev)) {

Ok, I¹ll update this.

>
>> +	} else if (has_acpi_companion(host)) {
>> +		adev = acpi_node(host->fwnode);
>> +		if (acpi_dma_is_supported(adev))
>> +			arch_setup_dma_ops(dev, 0, 0, NULL,
>> +					   acpi_dma_is_coherent(adev));
>> +	}
>> +
>> +	pci_put_host_bridge_device(bridge);
>> +}
>> +
>>  void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
>>  {
>>  	int ret;
>> @@ -1521,7 +1552,7 @@ void pci_device_add(struct pci_dev *dev, struct
>>pci_bus *bus)
>>  	dev->dev.dma_mask = &dev->dma_mask;
>>  	dev->dev.dma_parms = &dev->dma_parms;
>>  	dev->dev.coherent_dma_mask = 0xffffffffull;
>> -	of_pci_dma_configure(dev);
>> +	pci_dma_configure(dev);
>
>Also I'm not quite sure if that's actually OK.
>
>We should be handling the DMA setup on x86 in the ACPI case already
>without it.
>Or is this a NOP on x86?

You are correct. x86 doesn¹t implement the arch_setup_dma_ops().
Therefore, this is a NOP on x86.

Thanks,

Suravee
Suravee Suthikulpanit May 16, 2015, 3:14 p.m. UTC | #4
Hi Bjorn,

On 5/16/15, 07:41, "Bjorn Helgaas" <bhelgaas@google.com> wrote:

>On Fri, May 15, 2015 at 4:23 PM, Suravee Suthikulpanit
><Suravee.Suthikulpanit@amd.com> wrote:
>> This patch refactors of_pci_dma_configure() into a more generic
>> pci_dma_configure(), which can be reused by non-OF code.
>> Then, it adds support for setting up PCI device DMA coherency from
>> ACPI _CCA object that should normally be specified in the DSDT node
>> of its PCI host bridge..
>
>From the changelog, it sounds like you might be able to split this
>into two patches:
>
>1) Refactor of_pci_dma_configure(), with no functional change
>2) Add support for using _CCA
>
>If that's possible, please do so to make this easier to review.
>
>Bjorn

Yes, I can separate the patch out. This would mainly affect ACPI+PCI
support for ARM64 (which is in progress).

Thanks,

Surafvee
Catalin Marinas May 20, 2015, 9:24 a.m. UTC | #5
On Sat, May 16, 2015 at 01:59:00AM +0200, Rafael J. Wysocki wrote:
> On Friday, May 15, 2015 04:23:11 PM Suravee Suthikulpanit wrote:
> > +/**
> > + * pci_dma_configure - Setup DMA configuration
> > + * @pci_dev: ptr to pci_dev struct of the PCI device
> > + *
> > + * Function to update PCI devices's DMA configuration using the same
> > + * info from the OF node or ACPI node of host bridge's parent (if any).
> > + */
> > +static void pci_dma_configure(struct pci_dev *pci_dev)
> > +{
> > +	struct device *dev = &pci_dev->dev;
> > +	struct device *bridge = pci_get_host_bridge_device(pci_dev);
> > +	struct device *host = bridge->parent;
> > +	struct acpi_device *adev;
> > +
> > +	if (!host)
> > +		return;
> > +
> > +	if (acpi_disabled) {
> > +		of_dma_configure(dev, host->of_node);
> 
> I'd rather do
> 
> 	if (IS_ENABLED(CONFIG_OF) && host->of_node) {
> 		of_dma_configure(dev, host->of_node);

Nitpick: do we need the CONFIG_OF check? If disabled, I don't think
anyone would set host->of_node.
Arnd Bergmann May 20, 2015, 9:27 a.m. UTC | #6
On Wednesday 20 May 2015 10:24:15 Catalin Marinas wrote:
> On Sat, May 16, 2015 at 01:59:00AM +0200, Rafael J. Wysocki wrote:
> > On Friday, May 15, 2015 04:23:11 PM Suravee Suthikulpanit wrote:
> > > +/**
> > > + * pci_dma_configure - Setup DMA configuration
> > > + * @pci_dev: ptr to pci_dev struct of the PCI device
> > > + *
> > > + * Function to update PCI devices's DMA configuration using the same
> > > + * info from the OF node or ACPI node of host bridge's parent (if any).
> > > + */
> > > +static void pci_dma_configure(struct pci_dev *pci_dev)
> > > +{
> > > +   struct device *dev = &pci_dev->dev;
> > > +   struct device *bridge = pci_get_host_bridge_device(pci_dev);
> > > +   struct device *host = bridge->parent;
> > > +   struct acpi_device *adev;
> > > +
> > > +   if (!host)
> > > +           return;
> > > +
> > > +   if (acpi_disabled) {
> > > +           of_dma_configure(dev, host->of_node);
> > 
> > I'd rather do
> > 
> >       if (IS_ENABLED(CONFIG_OF) && host->of_node) {
> >               of_dma_configure(dev, host->of_node);
> 
> Nitpick: do we need the CONFIG_OF check? If disabled, I don't think
> anyone would set host->of_node.
> 

If of_dma_configure() is defined in a file that is built conditionally
based on CONFIG_OF, you need it.

	Arnd
Catalin Marinas May 20, 2015, 9:31 a.m. UTC | #7
On Wed, May 20, 2015 at 10:24:15AM +0100, Catalin Marinas wrote:
> On Sat, May 16, 2015 at 01:59:00AM +0200, Rafael J. Wysocki wrote:
> > On Friday, May 15, 2015 04:23:11 PM Suravee Suthikulpanit wrote:
> > > +/**
> > > + * pci_dma_configure - Setup DMA configuration
> > > + * @pci_dev: ptr to pci_dev struct of the PCI device
> > > + *
> > > + * Function to update PCI devices's DMA configuration using the same
> > > + * info from the OF node or ACPI node of host bridge's parent (if any).
> > > + */
> > > +static void pci_dma_configure(struct pci_dev *pci_dev)
> > > +{
> > > +	struct device *dev = &pci_dev->dev;
> > > +	struct device *bridge = pci_get_host_bridge_device(pci_dev);
> > > +	struct device *host = bridge->parent;
> > > +	struct acpi_device *adev;
> > > +
> > > +	if (!host)
> > > +		return;
> > > +
> > > +	if (acpi_disabled) {
> > > +		of_dma_configure(dev, host->of_node);
> > 
> > I'd rather do
> > 
> > 	if (IS_ENABLED(CONFIG_OF) && host->of_node) {
> > 		of_dma_configure(dev, host->of_node);
> 
> Nitpick: do we need the CONFIG_OF check? If disabled, I don't think
> anyone would set host->of_node.

Please ignore this, there is no point in checking host->of_node if
CONFIG_OF is disabled (I was just thinking from an arm64 perspective
where we always have CONFIG_OF enabled).
Catalin Marinas May 20, 2015, 9:34 a.m. UTC | #8
On Wed, May 20, 2015 at 11:27:54AM +0200, Arnd Bergmann wrote:
> On Wednesday 20 May 2015 10:24:15 Catalin Marinas wrote:
> > On Sat, May 16, 2015 at 01:59:00AM +0200, Rafael J. Wysocki wrote:
> > > On Friday, May 15, 2015 04:23:11 PM Suravee Suthikulpanit wrote:
> > > > +/**
> > > > + * pci_dma_configure - Setup DMA configuration
> > > > + * @pci_dev: ptr to pci_dev struct of the PCI device
> > > > + *
> > > > + * Function to update PCI devices's DMA configuration using the same
> > > > + * info from the OF node or ACPI node of host bridge's parent (if any).
> > > > + */
> > > > +static void pci_dma_configure(struct pci_dev *pci_dev)
> > > > +{
> > > > +   struct device *dev = &pci_dev->dev;
> > > > +   struct device *bridge = pci_get_host_bridge_device(pci_dev);
> > > > +   struct device *host = bridge->parent;
> > > > +   struct acpi_device *adev;
> > > > +
> > > > +   if (!host)
> > > > +           return;
> > > > +
> > > > +   if (acpi_disabled) {
> > > > +           of_dma_configure(dev, host->of_node);
> > > 
> > > I'd rather do
> > > 
> > >       if (IS_ENABLED(CONFIG_OF) && host->of_node) {
> > >               of_dma_configure(dev, host->of_node);
> > 
> > Nitpick: do we need the CONFIG_OF check? If disabled, I don't think
> > anyone would set host->of_node.
> 
> If of_dma_configure() is defined in a file that is built conditionally
> based on CONFIG_OF, you need it.

We have a dummy of_dma_configure() already when !CONFIG_OF, otherwise
we would need #ifndef here. I already replied, I think for other
architectures we need this check to avoid a useless host->of_node test.
Suravee Suthikulpanit May 20, 2015, noon UTC | #9
On 5/20/2015 4:34 AM, Catalin Marinas wrote:
> On Wed, May 20, 2015 at 11:27:54AM +0200, Arnd Bergmann wrote:
>> On Wednesday 20 May 2015 10:24:15 Catalin Marinas wrote:
>>> On Sat, May 16, 2015 at 01:59:00AM +0200, Rafael J. Wysocki wrote:
>>>> On Friday, May 15, 2015 04:23:11 PM Suravee Suthikulpanit wrote:
>>>>> +/**
>>>>> + * pci_dma_configure - Setup DMA configuration
>>>>> + * @pci_dev: ptr to pci_dev struct of the PCI device
>>>>> + *
>>>>> + * Function to update PCI devices's DMA configuration using the same
>>>>> + * info from the OF node or ACPI node of host bridge's parent (if any).
>>>>> + */
>>>>> +static void pci_dma_configure(struct pci_dev *pci_dev)
>>>>> +{
>>>>> +   struct device *dev = &pci_dev->dev;
>>>>> +   struct device *bridge = pci_get_host_bridge_device(pci_dev);
>>>>> +   struct device *host = bridge->parent;
>>>>> +   struct acpi_device *adev;
>>>>> +
>>>>> +   if (!host)
>>>>> +           return;
>>>>> +
>>>>> +   if (acpi_disabled) {
>>>>> +           of_dma_configure(dev, host->of_node);
>>>>
>>>> I'd rather do
>>>>
>>>>        if (IS_ENABLED(CONFIG_OF) && host->of_node) {
>>>>                of_dma_configure(dev, host->of_node);
>>>
>>> Nitpick: do we need the CONFIG_OF check? If disabled, I don't think
>>> anyone would set host->of_node.
>>
>> If of_dma_configure() is defined in a file that is built conditionally
>> based on CONFIG_OF, you need it.
>
> We have a dummy of_dma_configure() already when !CONFIG_OF, otherwise
> we would need #ifndef here. I already replied, I think for other
> architectures we need this check to avoid a useless host->of_node test.
>

It seems that there are several places that have similar check. Would it 
be good to convert this into a macro? Something like:

#define OF_NODE_ENABLED(dev)	(IS_ENABLED(CONFIG_OF) && dev->of_node)

Thanks all for the review feedback.

Suravee
Arnd Bergmann May 20, 2015, 12:02 p.m. UTC | #10
On Wednesday 20 May 2015 07:00:25 Suravee Suthikulanit wrote:
> It seems that there are several places that have similar check. Would it 
> be good to convert this into a macro? Something like:
> 
> #define OF_NODE_ENABLED(dev)    (IS_ENABLED(CONFIG_OF) && dev->of_node)
> 
> Thanks all for the review feedback.
> 

Better make that an inline function that returns the node:

struct device_node *dev_of_node(struct device *)
{
	if (IS_ENABLED(CONFIG_OF))
		return dev->of_node;

	return NULL;
}

	Arnd
Russell King - ARM Linux May 20, 2015, 8:46 p.m. UTC | #11
On Wed, May 20, 2015 at 07:00:25AM -0500, Suravee Suthikulanit wrote:
> On 5/20/2015 4:34 AM, Catalin Marinas wrote:
> >We have a dummy of_dma_configure() already when !CONFIG_OF, otherwise
> >we would need #ifndef here. I already replied, I think for other
> >architectures we need this check to avoid a useless host->of_node test.
> 
> It seems that there are several places that have similar check. Would it be
> good to convert this into a macro? Something like:
> 
> #define OF_NODE_ENABLED(dev)	(IS_ENABLED(CONFIG_OF) && dev->of_node)

This /could/ be a useful compile-time optimisation: when CONFIG_OF is
disabled, dev->of_node exists but will always be NULL - but the
compiler doesn't know this.  Your suggestion above would tell the
compiler that when CONFIG_OF is disabled, OF_NODE_ENABLED() will
evaluate to a constant false, which means it can eliminate code.
diff mbox

Patch

diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
index 5751dc5..b66ee4e 100644
--- a/drivers/of/of_pci.c
+++ b/drivers/of/of_pci.c
@@ -117,26 +117,6 @@  int of_get_pci_domain_nr(struct device_node *node)
 }
 EXPORT_SYMBOL_GPL(of_get_pci_domain_nr);
 
-/**
- * of_pci_dma_configure - Setup DMA configuration
- * @dev: ptr to pci_dev struct of the PCI device
- *
- * Function to update PCI devices's DMA configuration using the same
- * info from the OF node of host bridge's parent (if any).
- */
-void of_pci_dma_configure(struct pci_dev *pci_dev)
-{
-	struct device *dev = &pci_dev->dev;
-	struct device *bridge = pci_get_host_bridge_device(pci_dev);
-
-	if (!bridge->parent)
-		return;
-
-	of_dma_configure(dev, bridge->parent->of_node);
-	pci_put_host_bridge_device(bridge);
-}
-EXPORT_SYMBOL_GPL(of_pci_dma_configure);
-
 #if defined(CONFIG_OF_ADDRESS)
 /**
  * of_pci_get_host_bridge_resources - Parse PCI host bridge resources from DT
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 6675a7a..3c6f2e5 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -6,12 +6,14 @@ 
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/pci.h>
-#include <linux/of_pci.h>
+#include <linux/of_device.h>
 #include <linux/pci_hotplug.h>
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/cpumask.h>
 #include <linux/pci-aspm.h>
+#include <linux/acpi.h>
+#include <linux/property.h>
 #include <asm-generic/pci-bridge.h>
 #include "pci.h"
 
@@ -1508,6 +1510,35 @@  static void pci_init_capabilities(struct pci_dev *dev)
 	pci_enable_acs(dev);
 }
 
+/**
+ * pci_dma_configure - Setup DMA configuration
+ * @pci_dev: ptr to pci_dev struct of the PCI device
+ *
+ * Function to update PCI devices's DMA configuration using the same
+ * info from the OF node or ACPI node of host bridge's parent (if any).
+ */
+static void pci_dma_configure(struct pci_dev *pci_dev)
+{
+	struct device *dev = &pci_dev->dev;
+	struct device *bridge = pci_get_host_bridge_device(pci_dev);
+	struct device *host = bridge->parent;
+	struct acpi_device *adev;
+
+	if (!host)
+		return;
+
+	if (acpi_disabled) {
+		of_dma_configure(dev, host->of_node);
+	} else if (has_acpi_companion(host)) {
+		adev = acpi_node(host->fwnode);
+		if (acpi_dma_is_supported(adev))
+			arch_setup_dma_ops(dev, 0, 0, NULL,
+					   acpi_dma_is_coherent(adev));
+	}
+
+	pci_put_host_bridge_device(bridge);
+}
+
 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
 {
 	int ret;
@@ -1521,7 +1552,7 @@  void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
 	dev->dev.dma_mask = &dev->dma_mask;
 	dev->dev.dma_parms = &dev->dma_parms;
 	dev->dev.coherent_dma_mask = 0xffffffffull;
-	of_pci_dma_configure(dev);
+	pci_dma_configure(dev);
 
 	pci_set_dma_max_seg_size(dev, 65536);
 	pci_set_dma_seg_boundary(dev, 0xffffffff);
diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h
index 29fd3fe..ce0e5ab 100644
--- a/include/linux/of_pci.h
+++ b/include/linux/of_pci.h
@@ -16,7 +16,6 @@  int of_pci_get_devfn(struct device_node *np);
 int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin);
 int of_pci_parse_bus_range(struct device_node *node, struct resource *res);
 int of_get_pci_domain_nr(struct device_node *node);
-void of_pci_dma_configure(struct pci_dev *pci_dev);
 #else
 static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq)
 {
@@ -51,8 +50,6 @@  of_get_pci_domain_nr(struct device_node *node)
 {
 	return -1;
 }
-
-static inline void of_pci_dma_configure(struct pci_dev *pci_dev) { }
 #endif
 
 #if defined(CONFIG_OF_ADDRESS)