Re: [PATCH v4 4/6] drm/panfrost: Add support for AARCH64_4K page table format

[Ariel D'Alessandro <ariel.dalessandro@collabora.com>]

Adrian,

On 3/22/25 3:48 PM, Adrian Larumbe wrote:
> On 17.03.2025 11:52, Ariel D'Alessandro wrote:
>> Currently, Panfrost only supports MMU configuration in "LEGACY" (as
>> Bifrost calls it) mode, a (modified) version of LPAE "Large Physical
>> Address Extension", which in Linux we've called "mali_lpae".
>>
>> This commit adds support for conditionally enabling AARCH64_4K page
>> table format. To achieve that, a "GPU optional quirks" field was added
>> to `struct panfrost_features` with the related flag.
>>
>> Note that, in order to enable AARCH64_4K mode, the GPU variant must have
>> the HW_FEATURE_AARCH64_MMU feature flag present.
>>
>> Signed-off-by: Ariel D'Alessandro <ariel.dalessandro@collabora.com>
>> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>> Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
>> ---
>>   drivers/gpu/drm/panfrost/panfrost_device.h |  16 +++
>>   drivers/gpu/drm/panfrost/panfrost_mmu.c    | 140 +++++++++++++++++++--
>>   drivers/gpu/drm/panfrost/panfrost_regs.h   |  34 +++++
>>   3 files changed, 183 insertions(+), 7 deletions(-)

[snip]

>> diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c
>> index 294f86b3c25e7..506f42ccfd5fc 100644
>> --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
>> +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c

[snip]

>> +static int panfrost_mmu_cfg_init(struct panfrost_mmu *mmu,
>> +				  enum io_pgtable_fmt fmt)
>> +{
>> +	struct panfrost_device *pfdev = mmu->pfdev;
>> +
>> +	switch (fmt) {
>> +	case ARM_64_LPAE_S1:
>> +		return mmu_cfg_init_aarch64_4k(mmu);
>> +	case ARM_MALI_LPAE:
>> +		return mmu_cfg_init_mali_lpae(mmu);
>> +	default:
>> +		/* This should never happen */
>> +		drm_WARN(pfdev->ddev, "Invalid pgtable format");
> 
> I think there's a '1' missing here before the string literal.
> Other than that,
> 
> Reviewed-by: Adrián Larumbe <adrian.larumbe@collabora.com>

Fixed, thanks!

Will send v5 right away.

-- 
Ariel D'Alessandro
Software Engineer

Collabora Ltd.
Platinum Building, St John's Innovation Park, Cambridge CB4 0DS, UK 
Registered in England & Wales, no. 5513718