On 20.08.25 23:00, Deucher, Alexander wrote:
> [Public]
>
>> -----Original Message-----
>> From: SHANMUGAM, SRINIVASAN <srinivasan.shanmu...@amd.com>
>> Sent: Wednesday, August 20, 2025 7:33 AM
>> To: Koenig, Christian <christian.koe...@amd.com>; Deucher, Alexander
>> <alexander.deuc...@amd.com>
>> Cc: amd-gfx@lists.freedesktop.org; SHANMUGAM, SRINIVASAN
>> <srinivasan.shanmu...@amd.com>
>> Subject: [RFC PATCH 4/7] drm/amdgpu: Add mmio_remap fields to amdgpu_device
>>
>> Add bookkeeping for the remap page to struct amdgpu_device:
>>
>> * mmio_remap_bo (singleton BO)
>> * mmio_remap_base, mmio_remap_barsz (register BAR base/size)
>> * mmio_remap_offset (BAR-relative offset of the remap page)
>> * mmio_remap_size (PAGE_SIZE)
>
> It's not PAGE_SIZE it's 4K. If the PAGE_SIZE is >4K on the system, then we
> can't support this.
Please use AMDGPU_PAGE_SIZE for all defines, it should be 4k for current GPU HW
generations.
Regards,
Christian.
>
>>
>> Cc: Christian König <christian.koe...@amd.com>
>> Cc: Alex Deucher <alexander.deuc...@amd.com>
>> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmu...@amd.com>
>> ---
>> drivers/gpu/drm/amd/amdgpu/amdgpu.h | 7 +++++++
>> 1 file changed, 7 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> index ddd472e56f69..6c477596617b 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> @@ -1038,6 +1038,13 @@ struct amdgpu_device {
>> amdgpu_block_wreg_t audio_endpt_wreg;
>> struct amdgpu_doorbell doorbell;
>>
>> + /* ===== MMIO remap (HDP flush) bookkeeping ===== */
>> + struct amdgpu_bo *mmio_remap_bo; /* singleton BO */
>> + resource_size_t mmio_remap_base; /* REG BAR bus base
>> */
>> + resource_size_t mmio_remap_barsz; /* REG BAR size */
>> + resource_size_t mmio_remap_offset;/* BAR-relative
>> offset of
>> remap page */
>> + resource_size_t mmio_remap_size; /* always PAGE_SIZE
>> */
>
> Always 4K.
>
> Alex
>
>
>> +
>> /* clock/pll info */
>> struct amdgpu_clock clock;
>>
>> --
>> 2.34.1
>
