diff mbox

[RFC,part2,9/9] ACPI / GIC: Initialize GIC using the information in MADT

Message ID 1386088753-2850-10-git-send-email-hanjun.guo@linaro.org (mailing list archive)
State New, archived
Headers show

Commit Message

Hanjun Guo Dec. 3, 2013, 4:39 p.m. UTC
In MADT table, there are GIC cpu interface base address and
GIC distributor base address, use them to convert GIC to ACPI.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
---
 arch/arm64/kernel/irq.c      |    5 ++++
 drivers/acpi/plat/arm-core.c |   66 ++++++++++++++++++++++++++++++++++++------
 include/linux/acpi.h         |    6 ++++
 3 files changed, 68 insertions(+), 9 deletions(-)

Comments

Rob Herring Dec. 3, 2013, 5:09 p.m. UTC | #1
On Tue, Dec 3, 2013 at 10:39 AM, Hanjun Guo <hanjun.guo@linaro.org> wrote:
> In MADT table, there are GIC cpu interface base address and
> GIC distributor base address, use them to convert GIC to ACPI.
>
> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
> ---
>  arch/arm64/kernel/irq.c      |    5 ++++
>  drivers/acpi/plat/arm-core.c |   66 ++++++++++++++++++++++++++++++++++++------
>  include/linux/acpi.h         |    6 ++++
>  3 files changed, 68 insertions(+), 9 deletions(-)
>
> diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c
> index 473e5db..a9e68bf 100644
> --- a/arch/arm64/kernel/irq.c
> +++ b/arch/arm64/kernel/irq.c
> @@ -25,6 +25,7 @@
>  #include <linux/irq.h>
>  #include <linux/smp.h>
>  #include <linux/init.h>
> +#include <linux/acpi.h>
>  #include <linux/irqchip.h>
>  #include <linux/seq_file.h>
>  #include <linux/ratelimit.h>
> @@ -78,6 +79,10 @@ void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
>  void __init init_IRQ(void)
>  {
>         irqchip_init();
> +
> +       if (!handle_arch_irq)
> +               acpi_gic_init();
> +
>         if (!handle_arch_irq)
>                 panic("No interrupt controller found.");
>  }
> diff --git a/drivers/acpi/plat/arm-core.c b/drivers/acpi/plat/arm-core.c
> index 17c99e1..509b847 100644
> --- a/drivers/acpi/plat/arm-core.c
> +++ b/drivers/acpi/plat/arm-core.c
> @@ -29,6 +29,7 @@
>  #include <linux/module.h>
>  #include <linux/irq.h>
>  #include <linux/irqdomain.h>
> +#include <linux/irqchip/arm-gic.h>
>  #include <linux/slab.h>
>  #include <linux/bootmem.h>
>  #include <linux/ioport.h>
> @@ -211,11 +212,21 @@ acpi_parse_gic(struct acpi_subtable_header *header, const unsigned long end)
>         return 0;
>  }
>
> +#ifdef CONFIG_ARM_GIC

Perhaps this should go in the GIC code? This is more of a general
question of where init/probing code goes. For DT, this as been with
the driver code.

> +/*
> + * Hard code here, we can not get memory size from MADT (but FDT does),
> + * this size is described in ARMv8 foudation model's User Guide
> + */
> +#define GIC_DISTRIBUTOR_MEMORY_SIZE (SZ_8K)
> +#define GIC_CPU_INTERFACE_MEMORY_SIZE (SZ_4K)

You have the sizes swapped. The cpu interface has the DIR register at 0x1000.

> +
>  static int __init
>  acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>                                 const unsigned long end)
>  {
>         struct acpi_madt_generic_distributor *distributor = NULL;
> +       void __iomem *dist_base = NULL;
> +       void __iomem *cpu_base = NULL;

Initialization here is unnecessary.

>
>         distributor = (struct acpi_madt_generic_distributor *)header;
>
> @@ -224,8 +235,43 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>
>         acpi_table_print_madt_entry(header);
>
> +       /* GIC is initialised after page_init(), no need for early_ioremap */
> +       dist_base = ioremap(distributor->base_address,
> +                               GIC_CPU_INTERFACE_MEMORY_SIZE);

Should be GIC_DISTRIBUTOR_MEMORY_SIZE.

> +       if (!dist_base) {
> +               pr_warn(PREFIX "unable to map gic dist registers\n");
> +               return -ENOMEM;
> +       }
> +
> +       /*
> +        * acpi_lapic_addr is stored in acpi_parse_madt(),
> +        * so we can use it here for GIC init
> +        */
> +       if (acpi_lapic_addr) {

Checking this first would be cleaner.

> +               iounmap(dist_base);
> +               pr_warn(PREFIX "Invalid GIC cpu interface base address\n");
> +               return -EINVAL;
> +       }
> +
> +       cpu_base = ioremap(acpi_lapic_addr, GIC_CPU_INTERFACE_MEMORY_SIZE);

How are gic's with different cpu address per core going to be handled?

> +       if (!cpu_base) {
> +               iounmap(dist_base);
> +               pr_warn(PREFIX "unable to map gic cpu registers\n");

All the printks are a bit verbose for my tastes. I think a single
error print would suffice.

> +               return -ENOMEM;
> +       }
> +
> +       gic_init(distributor->gic_id, -1, dist_base, cpu_base);
> +
>         return 0;
>  }
> +#else
> +static int __init
> +acpi_parse_gic_distributor(struct acpi_subtable_header *header,
> +                               const unsigned long end)
> +{
> +       return -ENODEV;
> +}
> +#endif /* CONFIG_ARM_GIC */

A "if (!IS_ENABLED(CONFIG_ARM_GIC)) return;" in the above function
would eliminate this ifdef.

>
>  /*
>   * Parse GIC cpu interface related entries in MADT
> @@ -234,7 +280,7 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>  static int __init acpi_parse_madt_gic_entries(void)
>  {
>         int count;
> -
> +

Unnecessary whitespace change.

>         /*
>          * do a partial walk of MADT to determine how many CPUs
>          * we have including disabled CPUs
> @@ -468,19 +514,21 @@ static void __init acpi_process_madt(void)
>                  * Parse MADT GIC cpu interface entries
>                  */
>                 error = acpi_parse_madt_gic_entries();
> -               if (!error) {
> -                       /*
> -                        * Parse MADT GIC distributor entries
> -                        */
> -                       acpi_parse_madt_gic_distributor_entries();
> -               }
> +               if (!error)
> +                       pr_info("Using ACPI for processor (GIC) configuration information\n");
>         }
>
> -       pr_info("Using ACPI for processor (GIC) configuration information\n");
> -
>         return;
>  }
>
> +int __init acpi_gic_init(void)
> +{
> +       /*
> +        * Parse MADT GIC distributor entries
> +        */
> +       return acpi_parse_madt_gic_distributor_entries();
> +}
> +
>  /*
>   * acpi_boot_table_init() and acpi_boot_init()
>   *  called from setup_arch(), always.
> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
> index edd5806..58a4bf4 100644
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
> @@ -112,6 +112,7 @@ char * __acpi_map_table (unsigned long phys_addr, unsigned long size);
>  void __acpi_unmap_table(char *map, unsigned long size);
>  int early_acpi_boot_init(void);
>  int acpi_boot_init (void);
> +int acpi_gic_init(void);
>  void acpi_boot_table_init (void);
>  int acpi_mps_check (void);
>  int acpi_numa_init (void);
> @@ -444,6 +445,11 @@ static inline int acpi_boot_init(void)
>         return 0;
>  }
>
> +static inline int acpi_gic_init(void)
> +{
> +       return -ENODEV;
> +}
> +
>  static inline void acpi_boot_table_init(void)
>  {
>         return;
> --
> 1.7.9.5
>
>
> _______________________________________________
> linaro-kernel mailing list
> linaro-kernel@lists.linaro.org
> http://lists.linaro.org/mailman/listinfo/linaro-kernel
Marc Zyngier Dec. 3, 2013, 5:26 p.m. UTC | #2
Hi Hanjun,

On 03/12/13 16:39, Hanjun Guo wrote:
> In MADT table, there are GIC cpu interface base address and
> GIC distributor base address, use them to convert GIC to ACPI.
> 
> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
> ---
>  arch/arm64/kernel/irq.c      |    5 ++++
>  drivers/acpi/plat/arm-core.c |   66 ++++++++++++++++++++++++++++++++++++------
>  include/linux/acpi.h         |    6 ++++
>  3 files changed, 68 insertions(+), 9 deletions(-)
> 
> diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c
> index 473e5db..a9e68bf 100644
> --- a/arch/arm64/kernel/irq.c
> +++ b/arch/arm64/kernel/irq.c
> @@ -25,6 +25,7 @@
>  #include <linux/irq.h>
>  #include <linux/smp.h>
>  #include <linux/init.h>
> +#include <linux/acpi.h>
>  #include <linux/irqchip.h>
>  #include <linux/seq_file.h>
>  #include <linux/ratelimit.h>
> @@ -78,6 +79,10 @@ void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
>  void __init init_IRQ(void)
>  {
>  	irqchip_init();
> +
> +	if (!handle_arch_irq)
> +		acpi_gic_init();
> +

Why is the GIC hardcoded? How are you going to support other interrupt
controllers?

>  	if (!handle_arch_irq)
>  		panic("No interrupt controller found.");
>  }
> diff --git a/drivers/acpi/plat/arm-core.c b/drivers/acpi/plat/arm-core.c
> index 17c99e1..509b847 100644
> --- a/drivers/acpi/plat/arm-core.c
> +++ b/drivers/acpi/plat/arm-core.c
> @@ -29,6 +29,7 @@
>  #include <linux/module.h>
>  #include <linux/irq.h>
>  #include <linux/irqdomain.h>
> +#include <linux/irqchip/arm-gic.h>
>  #include <linux/slab.h>
>  #include <linux/bootmem.h>
>  #include <linux/ioport.h>
> @@ -211,11 +212,21 @@ acpi_parse_gic(struct acpi_subtable_header *header, const unsigned long end)
>  	return 0;
>  }
>  
> +#ifdef CONFIG_ARM_GIC
> +/*
> + * Hard code here, we can not get memory size from MADT (but FDT does),
> + * this size is described in ARMv8 foudation model's User Guide
> + */
> +#define GIC_DISTRIBUTOR_MEMORY_SIZE (SZ_8K)
> +#define GIC_CPU_INTERFACE_MEMORY_SIZE (SZ_4K)

Aside from the incorrect sizes, how do you plan to address the other
regions that the GICv2 specification describes?

>  static int __init
>  acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>  				const unsigned long end)
>  {
>  	struct acpi_madt_generic_distributor *distributor = NULL;
> +	void __iomem *dist_base = NULL;
> +	void __iomem *cpu_base = NULL;
>  
>  	distributor = (struct acpi_madt_generic_distributor *)header;
>  
> @@ -224,8 +235,43 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>  
>  	acpi_table_print_madt_entry(header);
>  
> +	/* GIC is initialised after page_init(), no need for early_ioremap */
> +	dist_base = ioremap(distributor->base_address,
> +				GIC_CPU_INTERFACE_MEMORY_SIZE);
> +	if (!dist_base) {
> +		pr_warn(PREFIX "unable to map gic dist registers\n");
> +		return -ENOMEM;
> +	}
> +
> +	/*
> +	 * acpi_lapic_addr is stored in acpi_parse_madt(),
> +	 * so we can use it here for GIC init
> +	 */
> +	if (acpi_lapic_addr) {
> +		iounmap(dist_base);
> +		pr_warn(PREFIX "Invalid GIC cpu interface base address\n");
> +		return -EINVAL;
> +	}
> +
> +	cpu_base = ioremap(acpi_lapic_addr, GIC_CPU_INTERFACE_MEMORY_SIZE);
> +	if (!cpu_base) {
> +		iounmap(dist_base);
> +		pr_warn(PREFIX "unable to map gic cpu registers\n");
> +		return -ENOMEM;
> +	}
> +
> +	gic_init(distributor->gic_id, -1, dist_base, cpu_base);
> +
>  	return 0;
>  }
> +#else
> +static int __init
> +acpi_parse_gic_distributor(struct acpi_subtable_header *header,
> +				const unsigned long end)
> +{
> +	return -ENODEV;
> +}
> +#endif /* CONFIG_ARM_GIC */
>  
>  /*
>   * Parse GIC cpu interface related entries in MADT
> @@ -234,7 +280,7 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>  static int __init acpi_parse_madt_gic_entries(void)
>  {
>  	int count;
> -
> + 
>  	/*
>  	 * do a partial walk of MADT to determine how many CPUs
>  	 * we have including disabled CPUs
> @@ -468,19 +514,21 @@ static void __init acpi_process_madt(void)
>  		 * Parse MADT GIC cpu interface entries
>  		 */
>  		error = acpi_parse_madt_gic_entries();
> -		if (!error) {
> -			/*
> -			 * Parse MADT GIC distributor entries
> -			 */
> -			acpi_parse_madt_gic_distributor_entries();
> -		}
> +		if (!error)
> +			pr_info("Using ACPI for processor (GIC) configuration information\n");
>  	}
>  
> -	pr_info("Using ACPI for processor (GIC) configuration information\n");
> -
>  	return;
>  }
>  
> +int __init acpi_gic_init(void)
> +{
> +	/*
> +	 * Parse MADT GIC distributor entries
> +	 */
> +	return acpi_parse_madt_gic_distributor_entries();
> +}
> +

Why can't you do the GIC init in the GIC code? We've tried hard to make
interrupt controllers discoverable and self contained. What are you
going to do when ACPI adds GICv3 to the mix? I don't really think this
model (shoving everything into the core ACPI code) is sustainable in the
long run...

Cheers,

	M.
Hanjun Guo Dec. 4, 2013, 2:58 p.m. UTC | #3
On 2013?12?04? 01:09, Rob Herring wrote:
> On Tue, Dec 3, 2013 at 10:39 AM, Hanjun Guo <hanjun.guo@linaro.org> wrote:
>> In MADT table, there are GIC cpu interface base address and
>> GIC distributor base address, use them to convert GIC to ACPI.
>>
>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
>> ---
>>   arch/arm64/kernel/irq.c      |    5 ++++
>>   drivers/acpi/plat/arm-core.c |   66 ++++++++++++++++++++++++++++++++++++------
>>   include/linux/acpi.h         |    6 ++++
>>   3 files changed, 68 insertions(+), 9 deletions(-)
>>
>> diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c
>> index 473e5db..a9e68bf 100644
>> --- a/arch/arm64/kernel/irq.c
>> +++ b/arch/arm64/kernel/irq.c
>> @@ -25,6 +25,7 @@
>>   #include <linux/irq.h>
>>   #include <linux/smp.h>
>>   #include <linux/init.h>
>> +#include <linux/acpi.h>
>>   #include <linux/irqchip.h>
>>   #include <linux/seq_file.h>
>>   #include <linux/ratelimit.h>
>> @@ -78,6 +79,10 @@ void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
>>   void __init init_IRQ(void)
>>   {
>>          irqchip_init();
>> +
>> +       if (!handle_arch_irq)
>> +               acpi_gic_init();
>> +
>>          if (!handle_arch_irq)
>>                  panic("No interrupt controller found.");
>>   }
>> diff --git a/drivers/acpi/plat/arm-core.c b/drivers/acpi/plat/arm-core.c
>> index 17c99e1..509b847 100644
>> --- a/drivers/acpi/plat/arm-core.c
>> +++ b/drivers/acpi/plat/arm-core.c
>> @@ -29,6 +29,7 @@
>>   #include <linux/module.h>
>>   #include <linux/irq.h>
>>   #include <linux/irqdomain.h>
>> +#include <linux/irqchip/arm-gic.h>
>>   #include <linux/slab.h>
>>   #include <linux/bootmem.h>
>>   #include <linux/ioport.h>
>> @@ -211,11 +212,21 @@ acpi_parse_gic(struct acpi_subtable_header *header, const unsigned long end)
>>          return 0;
>>   }
>>
>> +#ifdef CONFIG_ARM_GIC
> Perhaps this should go in the GIC code? This is more of a general
> question of where init/probing code goes. For DT, this as been with
> the driver code.

I'm ok with your suggestion, how about move the code to
drivers/irqchip/irq-gic.c ? is this make sense to you?

>> +/*
>> + * Hard code here, we can not get memory size from MADT (but FDT does),
>> + * this size is described in ARMv8 foudation model's User Guide
>> + */
>> +#define GIC_DISTRIBUTOR_MEMORY_SIZE (SZ_8K)
>> +#define GIC_CPU_INTERFACE_MEMORY_SIZE (SZ_4K)
> You have the sizes swapped. The cpu interface has the DIR register at 0x1000.

I will figure out the right size in next version.

>> +
>>   static int __init
>>   acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>                                  const unsigned long end)
>>   {
>>          struct acpi_madt_generic_distributor *distributor = NULL;
>> +       void __iomem *dist_base = NULL;
>> +       void __iomem *cpu_base = NULL;
> Initialization here is unnecessary.

ok, will update in next version.

>>          distributor = (struct acpi_madt_generic_distributor *)header;
>>
>> @@ -224,8 +235,43 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>
>>          acpi_table_print_madt_entry(header);
>>
>> +       /* GIC is initialised after page_init(), no need for early_ioremap */
>> +       dist_base = ioremap(distributor->base_address,
>> +                               GIC_CPU_INTERFACE_MEMORY_SIZE);
> Should be GIC_DISTRIBUTOR_MEMORY_SIZE.

Good catch

>> +       if (!dist_base) {
>> +               pr_warn(PREFIX "unable to map gic dist registers\n");
>> +               return -ENOMEM;
>> +       }
>> +
>> +       /*
>> +        * acpi_lapic_addr is stored in acpi_parse_madt(),
>> +        * so we can use it here for GIC init
>> +        */
>> +       if (acpi_lapic_addr) {
> Checking this first would be cleaner.

Agreed, thank you for the advice, will update it in next version.

>> +               iounmap(dist_base);
>> +               pr_warn(PREFIX "Invalid GIC cpu interface base address\n");
>> +               return -EINVAL;
>> +       }
>> +
>> +       cpu_base = ioremap(acpi_lapic_addr, GIC_CPU_INTERFACE_MEMORY_SIZE);
> How are gic's with different cpu address per core going to be handled?

do you mean some GIC without banked registers?
if yes, ACPI can handle that, in the GIC (GIC cpu interface) structure, there is
"Physical Base Address" per core, we can use it to handle gic's with different
cpu address per core.

This part of code is not implemented yet, if needed, will send out in next version.


>> +       if (!cpu_base) {
>> +               iounmap(dist_base);
>> +               pr_warn(PREFIX "unable to map gic cpu registers\n");
> All the printks are a bit verbose for my tastes. I think a single
> error print would suffice.

do you mean if meet some error, then got to a single error printk?

>> +               return -ENOMEM;
>> +       }
>> +
>> +       gic_init(distributor->gic_id, -1, dist_base, cpu_base);
>> +
>>          return 0;
>>   }
>> +#else
>> +static int __init
>> +acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>> +                               const unsigned long end)
>> +{
>> +       return -ENODEV;
>> +}
>> +#endif /* CONFIG_ARM_GIC */
> A "if (!IS_ENABLED(CONFIG_ARM_GIC)) return;" in the above function
> would eliminate this ifdef.

Thanks for the suggestion, will do it

>>   /*
>>    * Parse GIC cpu interface related entries in MADT
>> @@ -234,7 +280,7 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>   static int __init acpi_parse_madt_gic_entries(void)
>>   {
>>          int count;
>> -
>> +
> Unnecessary whitespace change.

will update it :)

Thanks
Hanjun
Hanjun Guo Dec. 4, 2013, 3:32 p.m. UTC | #4
On 2013?12?04? 01:26, Marc Zyngier wrote:
> Hi Hanjun,
>
> On 03/12/13 16:39, Hanjun Guo wrote:
>> In MADT table, there are GIC cpu interface base address and
>> GIC distributor base address, use them to convert GIC to ACPI.
>>
>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
>> ---
>>   arch/arm64/kernel/irq.c      |    5 ++++
>>   drivers/acpi/plat/arm-core.c |   66 ++++++++++++++++++++++++++++++++++++------
>>   include/linux/acpi.h         |    6 ++++
>>   3 files changed, 68 insertions(+), 9 deletions(-)
>>
>> diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c
>> index 473e5db..a9e68bf 100644
>> --- a/arch/arm64/kernel/irq.c
>> +++ b/arch/arm64/kernel/irq.c
>> @@ -25,6 +25,7 @@
>>   #include <linux/irq.h>
>>   #include <linux/smp.h>
>>   #include <linux/init.h>
>> +#include <linux/acpi.h>
>>   #include <linux/irqchip.h>
>>   #include <linux/seq_file.h>
>>   #include <linux/ratelimit.h>
>> @@ -78,6 +79,10 @@ void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
>>   void __init init_IRQ(void)
>>   {
>>   	irqchip_init();
>> +
>> +	if (!handle_arch_irq)
>> +		acpi_gic_init();
>> +
> Why is the GIC hardcoded?

Very good question, thanks. I considered GIC only in my patch set.
I have no idea how to handle the GIC hardcoded problem here for
now, but I will figure it out later.

If any suggestion, I will appreciate a lot.

> How are you going to support other interrupt
> controllers?

ACPI 5.0 supports GICv2 only for now, if we want to
support other interrupt controller, we should introduce
some OEM table and parsing it, and it will not covered
by this patch set.

>>   	if (!handle_arch_irq)
>>   		panic("No interrupt controller found.");
>>   }
>> diff --git a/drivers/acpi/plat/arm-core.c b/drivers/acpi/plat/arm-core.c
>> index 17c99e1..509b847 100644
>> --- a/drivers/acpi/plat/arm-core.c
>> +++ b/drivers/acpi/plat/arm-core.c
>> @@ -29,6 +29,7 @@
>>   #include <linux/module.h>
>>   #include <linux/irq.h>
>>   #include <linux/irqdomain.h>
>> +#include <linux/irqchip/arm-gic.h>
>>   #include <linux/slab.h>
>>   #include <linux/bootmem.h>
>>   #include <linux/ioport.h>
>> @@ -211,11 +212,21 @@ acpi_parse_gic(struct acpi_subtable_header *header, const unsigned long end)
>>   	return 0;
>>   }
>>   
>> +#ifdef CONFIG_ARM_GIC
>> +/*
>> + * Hard code here, we can not get memory size from MADT (but FDT does),
>> + * this size is described in ARMv8 foudation model's User Guide
>> + */
>> +#define GIC_DISTRIBUTOR_MEMORY_SIZE (SZ_8K)
>> +#define GIC_CPU_INTERFACE_MEMORY_SIZE (SZ_4K)
> Aside from the incorrect sizes, how do you plan to address the other
> regions that the GICv2 specification describes?

Did these regions have the same base address? I mean the same
as GIC distributor base address and GIC cpu interface base address.

if yes, since the base address is stored in gic_init(), it can be for 
furture
use. if I misunderstood your question, please let me know.

>>   static int __init
>>   acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>   				const unsigned long end)
>>   {
>>   	struct acpi_madt_generic_distributor *distributor = NULL;
>> +	void __iomem *dist_base = NULL;
>> +	void __iomem *cpu_base = NULL;
>>   
>>   	distributor = (struct acpi_madt_generic_distributor *)header;
>>   
>> @@ -224,8 +235,43 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>   
>>   	acpi_table_print_madt_entry(header);
>>   
>> +	/* GIC is initialised after page_init(), no need for early_ioremap */
>> +	dist_base = ioremap(distributor->base_address,
>> +				GIC_CPU_INTERFACE_MEMORY_SIZE);
>> +	if (!dist_base) {
>> +		pr_warn(PREFIX "unable to map gic dist registers\n");
>> +		return -ENOMEM;
>> +	}
>> +
>> +	/*
>> +	 * acpi_lapic_addr is stored in acpi_parse_madt(),
>> +	 * so we can use it here for GIC init
>> +	 */
>> +	if (acpi_lapic_addr) {
>> +		iounmap(dist_base);
>> +		pr_warn(PREFIX "Invalid GIC cpu interface base address\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	cpu_base = ioremap(acpi_lapic_addr, GIC_CPU_INTERFACE_MEMORY_SIZE);
>> +	if (!cpu_base) {
>> +		iounmap(dist_base);
>> +		pr_warn(PREFIX "unable to map gic cpu registers\n");
>> +		return -ENOMEM;
>> +	}
>> +
>> +	gic_init(distributor->gic_id, -1, dist_base, cpu_base);
>> +
>>   	return 0;
>>   }
>> +#else
>> +static int __init
>> +acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>> +				const unsigned long end)
>> +{
>> +	return -ENODEV;
>> +}
>> +#endif /* CONFIG_ARM_GIC */
>>   
>>   /*
>>    * Parse GIC cpu interface related entries in MADT
>> @@ -234,7 +280,7 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>   static int __init acpi_parse_madt_gic_entries(void)
>>   {
>>   	int count;
>> -
>> +
>>   	/*
>>   	 * do a partial walk of MADT to determine how many CPUs
>>   	 * we have including disabled CPUs
>> @@ -468,19 +514,21 @@ static void __init acpi_process_madt(void)
>>   		 * Parse MADT GIC cpu interface entries
>>   		 */
>>   		error = acpi_parse_madt_gic_entries();
>> -		if (!error) {
>> -			/*
>> -			 * Parse MADT GIC distributor entries
>> -			 */
>> -			acpi_parse_madt_gic_distributor_entries();
>> -		}
>> +		if (!error)
>> +			pr_info("Using ACPI for processor (GIC) configuration information\n");
>>   	}
>>   
>> -	pr_info("Using ACPI for processor (GIC) configuration information\n");
>> -
>>   	return;
>>   }
>>   
>> +int __init acpi_gic_init(void)
>> +{
>> +	/*
>> +	 * Parse MADT GIC distributor entries
>> +	 */
>> +	return acpi_parse_madt_gic_distributor_entries();
>> +}
>> +
> Why can't you do the GIC init in the GIC code? We've tried hard to make
> interrupt controllers discoverable and self contained.

thanks for your suggestion, Rob also had the same suggestion,
will try to update it in next version.

> What are you
> going to do when ACPI adds GICv3 to the mix? I don't really think this
> model (shoving everything into the core ACPI code) is sustainable in the
> long run...

Since GICv3 related ACPI proposal is not public and not goes into ACPI
spec, my suggestion is that we implement GICv2 only for now and post
another patches for GICv3 when the new ACPI spec is available.

Thanks
Hanjun
Marc Zyngier Dec. 4, 2013, 3:50 p.m. UTC | #5
On 04/12/13 15:32, Hanjun Guo wrote:
> On 2013?12?04? 01:26, Marc Zyngier wrote:
>> Hi Hanjun,
>>
>> On 03/12/13 16:39, Hanjun Guo wrote:
>>> In MADT table, there are GIC cpu interface base address and
>>> GIC distributor base address, use them to convert GIC to ACPI.
>>>
>>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
>>> ---
>>>   arch/arm64/kernel/irq.c      |    5 ++++
>>>   drivers/acpi/plat/arm-core.c |   66 ++++++++++++++++++++++++++++++++++++------
>>>   include/linux/acpi.h         |    6 ++++
>>>   3 files changed, 68 insertions(+), 9 deletions(-)
>>>
>>> diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c
>>> index 473e5db..a9e68bf 100644
>>> --- a/arch/arm64/kernel/irq.c
>>> +++ b/arch/arm64/kernel/irq.c
>>> @@ -25,6 +25,7 @@
>>>   #include <linux/irq.h>
>>>   #include <linux/smp.h>
>>>   #include <linux/init.h>
>>> +#include <linux/acpi.h>
>>>   #include <linux/irqchip.h>
>>>   #include <linux/seq_file.h>
>>>   #include <linux/ratelimit.h>
>>> @@ -78,6 +79,10 @@ void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
>>>   void __init init_IRQ(void)
>>>   {
>>>   	irqchip_init();
>>> +
>>> +	if (!handle_arch_irq)
>>> +		acpi_gic_init();
>>> +
>> Why is the GIC hardcoded?
> 
> Very good question, thanks. I considered GIC only in my patch set.
> I have no idea how to handle the GIC hardcoded problem here for
> now, but I will figure it out later.
> 
> If any suggestion, I will appreciate a lot.
> 
>> How are you going to support other interrupt
>> controllers?
> 
> ACPI 5.0 supports GICv2 only for now, if we want to
> support other interrupt controller, we should introduce
> some OEM table and parsing it, and it will not covered
> by this patch set.
> 
>>>   	if (!handle_arch_irq)
>>>   		panic("No interrupt controller found.");
>>>   }
>>> diff --git a/drivers/acpi/plat/arm-core.c b/drivers/acpi/plat/arm-core.c
>>> index 17c99e1..509b847 100644
>>> --- a/drivers/acpi/plat/arm-core.c
>>> +++ b/drivers/acpi/plat/arm-core.c
>>> @@ -29,6 +29,7 @@
>>>   #include <linux/module.h>
>>>   #include <linux/irq.h>
>>>   #include <linux/irqdomain.h>
>>> +#include <linux/irqchip/arm-gic.h>
>>>   #include <linux/slab.h>
>>>   #include <linux/bootmem.h>
>>>   #include <linux/ioport.h>
>>> @@ -211,11 +212,21 @@ acpi_parse_gic(struct acpi_subtable_header *header, const unsigned long end)
>>>   	return 0;
>>>   }
>>>   
>>> +#ifdef CONFIG_ARM_GIC
>>> +/*
>>> + * Hard code here, we can not get memory size from MADT (but FDT does),
>>> + * this size is described in ARMv8 foudation model's User Guide
>>> + */
>>> +#define GIC_DISTRIBUTOR_MEMORY_SIZE (SZ_8K)
>>> +#define GIC_CPU_INTERFACE_MEMORY_SIZE (SZ_4K)
>> Aside from the incorrect sizes, how do you plan to address the other
>> regions that the GICv2 specification describes?
> 
> Did these regions have the same base address? I mean the same
> as GIC distributor base address and GIC cpu interface base address.
> 
> if yes, since the base address is stored in gic_init(), it can be for 
> furture
> use. if I misunderstood your question, please let me know.

Look at the VGIC implementation for KVM in virt/kvm/arm. It does its own
probing of the additional regions used for virtualization.

The GIC and VGIC code are completely separate, and you'll need to find
an acceptable solution for that too.

>>>   static int __init
>>>   acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>>   				const unsigned long end)
>>>   {
>>>   	struct acpi_madt_generic_distributor *distributor = NULL;
>>> +	void __iomem *dist_base = NULL;
>>> +	void __iomem *cpu_base = NULL;
>>>   
>>>   	distributor = (struct acpi_madt_generic_distributor *)header;
>>>   
>>> @@ -224,8 +235,43 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>>   
>>>   	acpi_table_print_madt_entry(header);
>>>   
>>> +	/* GIC is initialised after page_init(), no need for early_ioremap */
>>> +	dist_base = ioremap(distributor->base_address,
>>> +				GIC_CPU_INTERFACE_MEMORY_SIZE);
>>> +	if (!dist_base) {
>>> +		pr_warn(PREFIX "unable to map gic dist registers\n");
>>> +		return -ENOMEM;
>>> +	}
>>> +
>>> +	/*
>>> +	 * acpi_lapic_addr is stored in acpi_parse_madt(),
>>> +	 * so we can use it here for GIC init
>>> +	 */
>>> +	if (acpi_lapic_addr) {
>>> +		iounmap(dist_base);
>>> +		pr_warn(PREFIX "Invalid GIC cpu interface base address\n");
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	cpu_base = ioremap(acpi_lapic_addr, GIC_CPU_INTERFACE_MEMORY_SIZE);
>>> +	if (!cpu_base) {
>>> +		iounmap(dist_base);
>>> +		pr_warn(PREFIX "unable to map gic cpu registers\n");
>>> +		return -ENOMEM;
>>> +	}
>>> +
>>> +	gic_init(distributor->gic_id, -1, dist_base, cpu_base);
>>> +
>>>   	return 0;
>>>   }
>>> +#else
>>> +static int __init
>>> +acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>> +				const unsigned long end)
>>> +{
>>> +	return -ENODEV;
>>> +}
>>> +#endif /* CONFIG_ARM_GIC */
>>>   
>>>   /*
>>>    * Parse GIC cpu interface related entries in MADT
>>> @@ -234,7 +280,7 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>>   static int __init acpi_parse_madt_gic_entries(void)
>>>   {
>>>   	int count;
>>> -
>>> +
>>>   	/*
>>>   	 * do a partial walk of MADT to determine how many CPUs
>>>   	 * we have including disabled CPUs
>>> @@ -468,19 +514,21 @@ static void __init acpi_process_madt(void)
>>>   		 * Parse MADT GIC cpu interface entries
>>>   		 */
>>>   		error = acpi_parse_madt_gic_entries();
>>> -		if (!error) {
>>> -			/*
>>> -			 * Parse MADT GIC distributor entries
>>> -			 */
>>> -			acpi_parse_madt_gic_distributor_entries();
>>> -		}
>>> +		if (!error)
>>> +			pr_info("Using ACPI for processor (GIC) configuration information\n");
>>>   	}
>>>   
>>> -	pr_info("Using ACPI for processor (GIC) configuration information\n");
>>> -
>>>   	return;
>>>   }
>>>   
>>> +int __init acpi_gic_init(void)
>>> +{
>>> +	/*
>>> +	 * Parse MADT GIC distributor entries
>>> +	 */
>>> +	return acpi_parse_madt_gic_distributor_entries();
>>> +}
>>> +
>> Why can't you do the GIC init in the GIC code? We've tried hard to make
>> interrupt controllers discoverable and self contained.
> 
> thanks for your suggestion, Rob also had the same suggestion,
> will try to update it in next version.
> 
>> What are you
>> going to do when ACPI adds GICv3 to the mix? I don't really think this
>> model (shoving everything into the core ACPI code) is sustainable in the
>> long run...
> 
> Since GICv3 related ACPI proposal is not public and not goes into ACPI
> spec, my suggestion is that we implement GICv2 only for now and post
> another patches for GICv3 when the new ACPI spec is available.

Certainly. But I think you should aim for a scalable solution right
away, instead of starting with something that we already know won't work
for stuff that is already around the corner (which is what I infer from
your "non public" statement).

Cheers,

	M.
Hanjun Guo Dec. 5, 2013, 1:41 p.m. UTC | #6
On 2013?12?04? 23:50, Marc Zyngier wrote:
> On 04/12/13 15:32, Hanjun Guo wrote:
>> On 2013?12?04? 01:26, Marc Zyngier wrote:
>>> Hi Hanjun,
>>>
>>> On 03/12/13 16:39, Hanjun Guo wrote:
>>>> In MADT table, there are GIC cpu interface base address and
>>>> GIC distributor base address, use them to convert GIC to ACPI.
>>>>
>>>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
>>>> ---
>>>>    arch/arm64/kernel/irq.c      |    5 ++++
>>>>    drivers/acpi/plat/arm-core.c |   66 ++++++++++++++++++++++++++++++++++++------
>>>>    include/linux/acpi.h         |    6 ++++
>>>>    3 files changed, 68 insertions(+), 9 deletions(-)
>>>>
>>>> diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c
>>>> index 473e5db..a9e68bf 100644
>>>> --- a/arch/arm64/kernel/irq.c
>>>> +++ b/arch/arm64/kernel/irq.c
>>>> @@ -25,6 +25,7 @@
>>>>    #include <linux/irq.h>
>>>>    #include <linux/smp.h>
>>>>    #include <linux/init.h>
>>>> +#include <linux/acpi.h>
>>>>    #include <linux/irqchip.h>
>>>>    #include <linux/seq_file.h>
>>>>    #include <linux/ratelimit.h>
>>>> @@ -78,6 +79,10 @@ void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
>>>>    void __init init_IRQ(void)
>>>>    {
>>>>    	irqchip_init();
>>>> +
>>>> +	if (!handle_arch_irq)
>>>> +		acpi_gic_init();
>>>> +
>>> Why is the GIC hardcoded?
>> Very good question, thanks. I considered GIC only in my patch set.
>> I have no idea how to handle the GIC hardcoded problem here for
>> now, but I will figure it out later.
>>
>> If any suggestion, I will appreciate a lot.
>>
>>> How are you going to support other interrupt
>>> controllers?
>> ACPI 5.0 supports GICv2 only for now, if we want to
>> support other interrupt controller, we should introduce
>> some OEM table and parsing it, and it will not covered
>> by this patch set.
>>
>>>>    	if (!handle_arch_irq)
>>>>    		panic("No interrupt controller found.");
>>>>    }
>>>> diff --git a/drivers/acpi/plat/arm-core.c b/drivers/acpi/plat/arm-core.c
>>>> index 17c99e1..509b847 100644
>>>> --- a/drivers/acpi/plat/arm-core.c
>>>> +++ b/drivers/acpi/plat/arm-core.c
>>>> @@ -29,6 +29,7 @@
>>>>    #include <linux/module.h>
>>>>    #include <linux/irq.h>
>>>>    #include <linux/irqdomain.h>
>>>> +#include <linux/irqchip/arm-gic.h>
>>>>    #include <linux/slab.h>
>>>>    #include <linux/bootmem.h>
>>>>    #include <linux/ioport.h>
>>>> @@ -211,11 +212,21 @@ acpi_parse_gic(struct acpi_subtable_header *header, const unsigned long end)
>>>>    	return 0;
>>>>    }
>>>>    
>>>> +#ifdef CONFIG_ARM_GIC
>>>> +/*
>>>> + * Hard code here, we can not get memory size from MADT (but FDT does),
>>>> + * this size is described in ARMv8 foudation model's User Guide
>>>> + */
>>>> +#define GIC_DISTRIBUTOR_MEMORY_SIZE (SZ_8K)
>>>> +#define GIC_CPU_INTERFACE_MEMORY_SIZE (SZ_4K)
>>> Aside from the incorrect sizes, how do you plan to address the other
>>> regions that the GICv2 specification describes?
>> Did these regions have the same base address? I mean the same
>> as GIC distributor base address and GIC cpu interface base address.
>>
>> if yes, since the base address is stored in gic_init(), it can be for
>> furture
>> use. if I misunderstood your question, please let me know.
> Look at the VGIC implementation for KVM in virt/kvm/arm. It does its own
> probing of the additional regions used for virtualization.
>
> The GIC and VGIC code are completely separate, and you'll need to find
> an acceptable solution for that too.

Ok, will review the VGIC code for KVM, thanks for the guidance.

>>>>    static int __init
>>>>    acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>>>    				const unsigned long end)
>>>>    {
>>>>    	struct acpi_madt_generic_distributor *distributor = NULL;
>>>> +	void __iomem *dist_base = NULL;
>>>> +	void __iomem *cpu_base = NULL;
>>>>    
>>>>    	distributor = (struct acpi_madt_generic_distributor *)header;
>>>>    
>>>> @@ -224,8 +235,43 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>>>    
>>>>    	acpi_table_print_madt_entry(header);
>>>>    
>>>> +	/* GIC is initialised after page_init(), no need for early_ioremap */
>>>> +	dist_base = ioremap(distributor->base_address,
>>>> +				GIC_CPU_INTERFACE_MEMORY_SIZE);
>>>> +	if (!dist_base) {
>>>> +		pr_warn(PREFIX "unable to map gic dist registers\n");
>>>> +		return -ENOMEM;
>>>> +	}
>>>> +
>>>> +	/*
>>>> +	 * acpi_lapic_addr is stored in acpi_parse_madt(),
>>>> +	 * so we can use it here for GIC init
>>>> +	 */
>>>> +	if (acpi_lapic_addr) {
>>>> +		iounmap(dist_base);
>>>> +		pr_warn(PREFIX "Invalid GIC cpu interface base address\n");
>>>> +		return -EINVAL;
>>>> +	}
>>>> +
>>>> +	cpu_base = ioremap(acpi_lapic_addr, GIC_CPU_INTERFACE_MEMORY_SIZE);
>>>> +	if (!cpu_base) {
>>>> +		iounmap(dist_base);
>>>> +		pr_warn(PREFIX "unable to map gic cpu registers\n");
>>>> +		return -ENOMEM;
>>>> +	}
>>>> +
>>>> +	gic_init(distributor->gic_id, -1, dist_base, cpu_base);
>>>> +
>>>>    	return 0;
>>>>    }
>>>> +#else
>>>> +static int __init
>>>> +acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>>> +				const unsigned long end)
>>>> +{
>>>> +	return -ENODEV;
>>>> +}
>>>> +#endif /* CONFIG_ARM_GIC */
>>>>    
>>>>    /*
>>>>     * Parse GIC cpu interface related entries in MADT
>>>> @@ -234,7 +280,7 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
>>>>    static int __init acpi_parse_madt_gic_entries(void)
>>>>    {
>>>>    	int count;
>>>> -
>>>> +
>>>>    	/*
>>>>    	 * do a partial walk of MADT to determine how many CPUs
>>>>    	 * we have including disabled CPUs
>>>> @@ -468,19 +514,21 @@ static void __init acpi_process_madt(void)
>>>>    		 * Parse MADT GIC cpu interface entries
>>>>    		 */
>>>>    		error = acpi_parse_madt_gic_entries();
>>>> -		if (!error) {
>>>> -			/*
>>>> -			 * Parse MADT GIC distributor entries
>>>> -			 */
>>>> -			acpi_parse_madt_gic_distributor_entries();
>>>> -		}
>>>> +		if (!error)
>>>> +			pr_info("Using ACPI for processor (GIC) configuration information\n");
>>>>    	}
>>>>    
>>>> -	pr_info("Using ACPI for processor (GIC) configuration information\n");
>>>> -
>>>>    	return;
>>>>    }
>>>>    
>>>> +int __init acpi_gic_init(void)
>>>> +{
>>>> +	/*
>>>> +	 * Parse MADT GIC distributor entries
>>>> +	 */
>>>> +	return acpi_parse_madt_gic_distributor_entries();
>>>> +}
>>>> +
>>> Why can't you do the GIC init in the GIC code? We've tried hard to make
>>> interrupt controllers discoverable and self contained.
>> thanks for your suggestion, Rob also had the same suggestion,
>> will try to update it in next version.
>>
>>> What are you
>>> going to do when ACPI adds GICv3 to the mix? I don't really think this
>>> model (shoving everything into the core ACPI code) is sustainable in the
>>> long run...
>> Since GICv3 related ACPI proposal is not public and not goes into ACPI
>> spec, my suggestion is that we implement GICv2 only for now and post
>> another patches for GICv3 when the new ACPI spec is available.
> Certainly. But I think you should aim for a scalable solution right
> away, instead of starting with something that we already know won't work
> for stuff that is already around the corner (which is what I infer from
> your "non public" statement).

yes, sure I will, thanks for your comments.

Thanks
Hanjun
Olof Johansson Dec. 9, 2013, 6:54 p.m. UTC | #7
On Wed, Dec 04, 2013 at 03:50:17PM +0000, Marc Zyngier wrote:
> On 04/12/13 15:32, Hanjun Guo wrote:
> > On 2013?12?04? 01:26, Marc Zyngier wrote:
> >> Hi Hanjun,
> >>
> >> On 03/12/13 16:39, Hanjun Guo wrote:
> >>> In MADT table, there are GIC cpu interface base address and
> >>> GIC distributor base address, use them to convert GIC to ACPI.
> >>>
> >>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
> >>> ---
> >>>   arch/arm64/kernel/irq.c      |    5 ++++
> >>>   drivers/acpi/plat/arm-core.c |   66 ++++++++++++++++++++++++++++++++++++------
> >>>   include/linux/acpi.h         |    6 ++++
> >>>   3 files changed, 68 insertions(+), 9 deletions(-)
> >>>
> >>> diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c
> >>> index 473e5db..a9e68bf 100644
> >>> --- a/arch/arm64/kernel/irq.c
> >>> +++ b/arch/arm64/kernel/irq.c
> >>> @@ -25,6 +25,7 @@
> >>>   #include <linux/irq.h>
> >>>   #include <linux/smp.h>
> >>>   #include <linux/init.h>
> >>> +#include <linux/acpi.h>
> >>>   #include <linux/irqchip.h>
> >>>   #include <linux/seq_file.h>
> >>>   #include <linux/ratelimit.h>
> >>> @@ -78,6 +79,10 @@ void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
> >>>   void __init init_IRQ(void)
> >>>   {
> >>>   	irqchip_init();
> >>> +
> >>> +	if (!handle_arch_irq)
> >>> +		acpi_gic_init();
> >>> +
> >> Why is the GIC hardcoded?
> > 
> > Very good question, thanks. I considered GIC only in my patch set.
> > I have no idea how to handle the GIC hardcoded problem here for
> > now, but I will figure it out later.
> > 
> > If any suggestion, I will appreciate a lot.
> > 
> >> How are you going to support other interrupt
> >> controllers?
> > 
> > ACPI 5.0 supports GICv2 only for now, if we want to
> > support other interrupt controller, we should introduce
> > some OEM table and parsing it, and it will not covered
> > by this patch set.
> > 
> >>>   	if (!handle_arch_irq)
> >>>   		panic("No interrupt controller found.");
> >>>   }
> >>> diff --git a/drivers/acpi/plat/arm-core.c b/drivers/acpi/plat/arm-core.c
> >>> index 17c99e1..509b847 100644
> >>> --- a/drivers/acpi/plat/arm-core.c
> >>> +++ b/drivers/acpi/plat/arm-core.c
> >>> @@ -29,6 +29,7 @@
> >>>   #include <linux/module.h>
> >>>   #include <linux/irq.h>
> >>>   #include <linux/irqdomain.h>
> >>> +#include <linux/irqchip/arm-gic.h>
> >>>   #include <linux/slab.h>
> >>>   #include <linux/bootmem.h>
> >>>   #include <linux/ioport.h>
> >>> @@ -211,11 +212,21 @@ acpi_parse_gic(struct acpi_subtable_header *header, const unsigned long end)
> >>>   	return 0;
> >>>   }
> >>>   
> >>> +#ifdef CONFIG_ARM_GIC
> >>> +/*
> >>> + * Hard code here, we can not get memory size from MADT (but FDT does),
> >>> + * this size is described in ARMv8 foudation model's User Guide
> >>> + */
> >>> +#define GIC_DISTRIBUTOR_MEMORY_SIZE (SZ_8K)
> >>> +#define GIC_CPU_INTERFACE_MEMORY_SIZE (SZ_4K)
> >> Aside from the incorrect sizes, how do you plan to address the other
> >> regions that the GICv2 specification describes?
> > 
> > Did these regions have the same base address? I mean the same
> > as GIC distributor base address and GIC cpu interface base address.
> > 
> > if yes, since the base address is stored in gic_init(), it can be for 
> > furture
> > use. if I misunderstood your question, please let me know.
> 
> Look at the VGIC implementation for KVM in virt/kvm/arm. It does its own
> probing of the additional regions used for virtualization.
> 
> The GIC and VGIC code are completely separate, and you'll need to find
> an acceptable solution for that too.
> 
> >>>   static int __init
> >>>   acpi_parse_gic_distributor(struct acpi_subtable_header *header,
> >>>   				const unsigned long end)
> >>>   {
> >>>   	struct acpi_madt_generic_distributor *distributor = NULL;
> >>> +	void __iomem *dist_base = NULL;
> >>> +	void __iomem *cpu_base = NULL;
> >>>   
> >>>   	distributor = (struct acpi_madt_generic_distributor *)header;
> >>>   
> >>> @@ -224,8 +235,43 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
> >>>   
> >>>   	acpi_table_print_madt_entry(header);
> >>>   
> >>> +	/* GIC is initialised after page_init(), no need for early_ioremap */
> >>> +	dist_base = ioremap(distributor->base_address,
> >>> +				GIC_CPU_INTERFACE_MEMORY_SIZE);
> >>> +	if (!dist_base) {
> >>> +		pr_warn(PREFIX "unable to map gic dist registers\n");
> >>> +		return -ENOMEM;
> >>> +	}
> >>> +
> >>> +	/*
> >>> +	 * acpi_lapic_addr is stored in acpi_parse_madt(),
> >>> +	 * so we can use it here for GIC init
> >>> +	 */
> >>> +	if (acpi_lapic_addr) {
> >>> +		iounmap(dist_base);
> >>> +		pr_warn(PREFIX "Invalid GIC cpu interface base address\n");
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	cpu_base = ioremap(acpi_lapic_addr, GIC_CPU_INTERFACE_MEMORY_SIZE);
> >>> +	if (!cpu_base) {
> >>> +		iounmap(dist_base);
> >>> +		pr_warn(PREFIX "unable to map gic cpu registers\n");
> >>> +		return -ENOMEM;
> >>> +	}
> >>> +
> >>> +	gic_init(distributor->gic_id, -1, dist_base, cpu_base);
> >>> +
> >>>   	return 0;
> >>>   }
> >>> +#else
> >>> +static int __init
> >>> +acpi_parse_gic_distributor(struct acpi_subtable_header *header,
> >>> +				const unsigned long end)
> >>> +{
> >>> +	return -ENODEV;
> >>> +}
> >>> +#endif /* CONFIG_ARM_GIC */
> >>>   
> >>>   /*
> >>>    * Parse GIC cpu interface related entries in MADT
> >>> @@ -234,7 +280,7 @@ acpi_parse_gic_distributor(struct acpi_subtable_header *header,
> >>>   static int __init acpi_parse_madt_gic_entries(void)
> >>>   {
> >>>   	int count;
> >>> -
> >>> +
> >>>   	/*
> >>>   	 * do a partial walk of MADT to determine how many CPUs
> >>>   	 * we have including disabled CPUs
> >>> @@ -468,19 +514,21 @@ static void __init acpi_process_madt(void)
> >>>   		 * Parse MADT GIC cpu interface entries
> >>>   		 */
> >>>   		error = acpi_parse_madt_gic_entries();
> >>> -		if (!error) {
> >>> -			/*
> >>> -			 * Parse MADT GIC distributor entries
> >>> -			 */
> >>> -			acpi_parse_madt_gic_distributor_entries();
> >>> -		}
> >>> +		if (!error)
> >>> +			pr_info("Using ACPI for processor (GIC) configuration information\n");
> >>>   	}
> >>>   
> >>> -	pr_info("Using ACPI for processor (GIC) configuration information\n");
> >>> -
> >>>   	return;
> >>>   }
> >>>   
> >>> +int __init acpi_gic_init(void)
> >>> +{
> >>> +	/*
> >>> +	 * Parse MADT GIC distributor entries
> >>> +	 */
> >>> +	return acpi_parse_madt_gic_distributor_entries();
> >>> +}
> >>> +
> >> Why can't you do the GIC init in the GIC code? We've tried hard to make
> >> interrupt controllers discoverable and self contained.
> > 
> > thanks for your suggestion, Rob also had the same suggestion,
> > will try to update it in next version.
> > 
> >> What are you
> >> going to do when ACPI adds GICv3 to the mix? I don't really think this
> >> model (shoving everything into the core ACPI code) is sustainable in the
> >> long run...
> > 
> > Since GICv3 related ACPI proposal is not public and not goes into ACPI
> > spec, my suggestion is that we implement GICv2 only for now and post
> > another patches for GICv3 when the new ACPI spec is available.
> 
> Certainly. But I think you should aim for a scalable solution right
> away, instead of starting with something that we already know won't work
> for stuff that is already around the corner (which is what I infer from
> your "non public" statement).

Again, I wonder if we might be better off converting GIC info (since
it's likely to be there on all systems) in the EFI boot wrapper into
FDT data when ACPI is provided.

Essentially, if we can describe:
* Memory
* Console uart (if one exists) for debug
* Timers
* Interrupts
(Possibly PCI host controllers too but I'm less sure that can be done
generically)

in the FDT stub, then we can keep a lot of the lowlevel init code common
instead of diverging. We can also get away from having to update both ACPI and
DT for GICv3, etc, reducing boilerplate code in the kernel to handle both.

If we have to add some properties to bring across some ACPI information we can
of course do so, hopefully it'll be a small amount.


-Olof
diff mbox

Patch

diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c
index 473e5db..a9e68bf 100644
--- a/arch/arm64/kernel/irq.c
+++ b/arch/arm64/kernel/irq.c
@@ -25,6 +25,7 @@ 
 #include <linux/irq.h>
 #include <linux/smp.h>
 #include <linux/init.h>
+#include <linux/acpi.h>
 #include <linux/irqchip.h>
 #include <linux/seq_file.h>
 #include <linux/ratelimit.h>
@@ -78,6 +79,10 @@  void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
 void __init init_IRQ(void)
 {
 	irqchip_init();
+
+	if (!handle_arch_irq)
+		acpi_gic_init();
+
 	if (!handle_arch_irq)
 		panic("No interrupt controller found.");
 }
diff --git a/drivers/acpi/plat/arm-core.c b/drivers/acpi/plat/arm-core.c
index 17c99e1..509b847 100644
--- a/drivers/acpi/plat/arm-core.c
+++ b/drivers/acpi/plat/arm-core.c
@@ -29,6 +29,7 @@ 
 #include <linux/module.h>
 #include <linux/irq.h>
 #include <linux/irqdomain.h>
+#include <linux/irqchip/arm-gic.h>
 #include <linux/slab.h>
 #include <linux/bootmem.h>
 #include <linux/ioport.h>
@@ -211,11 +212,21 @@  acpi_parse_gic(struct acpi_subtable_header *header, const unsigned long end)
 	return 0;
 }
 
+#ifdef CONFIG_ARM_GIC
+/*
+ * Hard code here, we can not get memory size from MADT (but FDT does),
+ * this size is described in ARMv8 foudation model's User Guide
+ */
+#define GIC_DISTRIBUTOR_MEMORY_SIZE (SZ_8K)
+#define GIC_CPU_INTERFACE_MEMORY_SIZE (SZ_4K)
+
 static int __init
 acpi_parse_gic_distributor(struct acpi_subtable_header *header,
 				const unsigned long end)
 {
 	struct acpi_madt_generic_distributor *distributor = NULL;
+	void __iomem *dist_base = NULL;
+	void __iomem *cpu_base = NULL;
 
 	distributor = (struct acpi_madt_generic_distributor *)header;
 
@@ -224,8 +235,43 @@  acpi_parse_gic_distributor(struct acpi_subtable_header *header,
 
 	acpi_table_print_madt_entry(header);
 
+	/* GIC is initialised after page_init(), no need for early_ioremap */
+	dist_base = ioremap(distributor->base_address,
+				GIC_CPU_INTERFACE_MEMORY_SIZE);
+	if (!dist_base) {
+		pr_warn(PREFIX "unable to map gic dist registers\n");
+		return -ENOMEM;
+	}
+
+	/*
+	 * acpi_lapic_addr is stored in acpi_parse_madt(),
+	 * so we can use it here for GIC init
+	 */
+	if (acpi_lapic_addr) {
+		iounmap(dist_base);
+		pr_warn(PREFIX "Invalid GIC cpu interface base address\n");
+		return -EINVAL;
+	}
+
+	cpu_base = ioremap(acpi_lapic_addr, GIC_CPU_INTERFACE_MEMORY_SIZE);
+	if (!cpu_base) {
+		iounmap(dist_base);
+		pr_warn(PREFIX "unable to map gic cpu registers\n");
+		return -ENOMEM;
+	}
+
+	gic_init(distributor->gic_id, -1, dist_base, cpu_base);
+
 	return 0;
 }
+#else
+static int __init
+acpi_parse_gic_distributor(struct acpi_subtable_header *header,
+				const unsigned long end)
+{
+	return -ENODEV;
+}
+#endif /* CONFIG_ARM_GIC */
 
 /*
  * Parse GIC cpu interface related entries in MADT
@@ -234,7 +280,7 @@  acpi_parse_gic_distributor(struct acpi_subtable_header *header,
 static int __init acpi_parse_madt_gic_entries(void)
 {
 	int count;
-
+ 
 	/*
 	 * do a partial walk of MADT to determine how many CPUs
 	 * we have including disabled CPUs
@@ -468,19 +514,21 @@  static void __init acpi_process_madt(void)
 		 * Parse MADT GIC cpu interface entries
 		 */
 		error = acpi_parse_madt_gic_entries();
-		if (!error) {
-			/*
-			 * Parse MADT GIC distributor entries
-			 */
-			acpi_parse_madt_gic_distributor_entries();
-		}
+		if (!error)
+			pr_info("Using ACPI for processor (GIC) configuration information\n");
 	}
 
-	pr_info("Using ACPI for processor (GIC) configuration information\n");
-
 	return;
 }
 
+int __init acpi_gic_init(void)
+{
+	/*
+	 * Parse MADT GIC distributor entries
+	 */
+	return acpi_parse_madt_gic_distributor_entries();
+}
+
 /*
  * acpi_boot_table_init() and acpi_boot_init()
  *  called from setup_arch(), always.
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index edd5806..58a4bf4 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -112,6 +112,7 @@  char * __acpi_map_table (unsigned long phys_addr, unsigned long size);
 void __acpi_unmap_table(char *map, unsigned long size);
 int early_acpi_boot_init(void);
 int acpi_boot_init (void);
+int acpi_gic_init(void);
 void acpi_boot_table_init (void);
 int acpi_mps_check (void);
 int acpi_numa_init (void);
@@ -444,6 +445,11 @@  static inline int acpi_boot_init(void)
 	return 0;
 }
 
+static inline int acpi_gic_init(void)
+{
+	return -ENODEV;
+}
+
 static inline void acpi_boot_table_init(void)
 {
 	return;