2017-06-08 08:57:49

by Lorenzo Pieralisi

[permalink] [raw]
Subject: Re: [PATCH v7 1/3] ACPI/IORT: Fixup SMMUv3 resource size for Cavium ThunderX2 SMMUv3 model

On Tue, May 30, 2017 at 05:33:39PM +0530, Geetha sowjanya wrote:
> From: Linu Cherian <[email protected]>
>
> Cavium ThunderX2 implementation doesn't support second page in SMMU
> register space. Hence, resource size is set as 64k for this model.
>
> Signed-off-by: Linu Cherian <[email protected]>
> Signed-off-by: Geetha Sowjanya <[email protected]>
> ---
> drivers/acpi/arm64/iort.c | 10 +++++++++-
> 1 files changed, 9 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> index c5fecf9..bba2b59 100644
> --- a/drivers/acpi/arm64/iort.c
> +++ b/drivers/acpi/arm64/iort.c
> @@ -833,12 +833,20 @@ static void __init arm_smmu_v3_init_resources(struct resource *res,
> {
> struct acpi_iort_smmu_v3 *smmu;
> int num_res = 0;
> + unsigned long size = SZ_128K;
>
> /* Retrieve SMMUv3 specific data */
> smmu = (struct acpi_iort_smmu_v3 *)node->node_data;
>
> + /*
> + * Override the size, for Cavium ThunderX2 implementation
> + * which doesn't support the page 1 SMMU register space.
> + */
> + if (smmu->model == ACPI_IORT_SMMU_CAVIUM_CN99XX)
> + size = SZ_64K;

Nit: add a function, say arm_smmu_v3_resource_size() with the logic
above that by default returns SZ_128K, I do not like this switch
in the middle of this function.

Lorenzo

> +
> res[num_res].start = smmu->base_address;
> - res[num_res].end = smmu->base_address + SZ_128K - 1;
> + res[num_res].end = smmu->base_address + size - 1;
> res[num_res].flags = IORESOURCE_MEM;
>
> num_res++;
> --
> 1.7.1
>


2017-06-09 06:00:58

by Geetha Akula

[permalink] [raw]
Subject: Re: [PATCH v7 1/3] ACPI/IORT: Fixup SMMUv3 resource size for Cavium ThunderX2 SMMUv3 model

On Thu, Jun 8, 2017 at 2:28 PM, Lorenzo Pieralisi
<[email protected]> wrote:
> On Tue, May 30, 2017 at 05:33:39PM +0530, Geetha sowjanya wrote:
>> From: Linu Cherian <[email protected]>
>>
>> Cavium ThunderX2 implementation doesn't support second page in SMMU
>> register space. Hence, resource size is set as 64k for this model.
>>
>> Signed-off-by: Linu Cherian <[email protected]>
>> Signed-off-by: Geetha Sowjanya <[email protected]>
>> ---
>> drivers/acpi/arm64/iort.c | 10 +++++++++-
>> 1 files changed, 9 insertions(+), 1 deletions(-)
>>
>> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
>> index c5fecf9..bba2b59 100644
>> --- a/drivers/acpi/arm64/iort.c
>> +++ b/drivers/acpi/arm64/iort.c
>> @@ -833,12 +833,20 @@ static void __init arm_smmu_v3_init_resources(struct resource *res,
>> {
>> struct acpi_iort_smmu_v3 *smmu;
>> int num_res = 0;
>> + unsigned long size = SZ_128K;
>>
>> /* Retrieve SMMUv3 specific data */
>> smmu = (struct acpi_iort_smmu_v3 *)node->node_data;
>>
>> + /*
>> + * Override the size, for Cavium ThunderX2 implementation
>> + * which doesn't support the page 1 SMMU register space.
>> + */
>> + if (smmu->model == ACPI_IORT_SMMU_CAVIUM_CN99XX)
>> + size = SZ_64K;
>
> Nit: add a function, say arm_smmu_v3_resource_size() with the logic
> above that by default returns SZ_128K, I do not like this switch
> in the middle of this function.

I will resubmit the patch with suggested changes.


Thanks,
Geetha.
>
> Lorenzo
>
>> +
>> res[num_res].start = smmu->base_address;
>> - res[num_res].end = smmu->base_address + SZ_128K - 1;
>> + res[num_res].end = smmu->base_address + size - 1;
>> res[num_res].flags = IORESOURCE_MEM;
>>
>> num_res++;
>> --
>> 1.7.1
>>