On Wed, May 17, 2023 at 12:26 PM Joshi, Mukul <Mukul.Joshi@xxxxxxx> wrote:
>
> [AMD Official Use Only - General]
>
>
> Hi Alex,
>
> ________________________________
> From: amd-gfx <amd-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx> on behalf of Alex Deucher <alexander.deucher@xxxxxxx>
> Sent: Wednesday, May 17, 2023 10:31 AM
> To: amd-gfx@xxxxxxxxxxxxxxxxxxxxx <amd-gfx@xxxxxxxxxxxxxxxxxxxxx>
> Cc: Deucher, Alexander <Alexander.Deucher@xxxxxxx>; Chen, Guchun <Guchun.Chen@xxxxxxx>
> Subject: [PATCH] drm/amdgpu/gmc9: fix 64 bit division in partition code
>
> Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
>
>
> Rework logic or use do_div() to avoid problems on 32 bit.
>
> v2: add a missing case for XCP macro
>
> Acked-by: Guchun Chen <guchun.chen@xxxxxxx> (v1)
> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c | 14 ++++++++++++++
> drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h | 9 ++++-----
> drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 5 ++++-
> drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c | 11 ++++++-----
> 4 files changed, 28 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c
> index 739eb7c0d133..fed545cdd1de 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c
> @@ -794,3 +794,17 @@ void amdgpu_amdkfd_unlock_kfd(struct amdgpu_device *adev)
> {
> kgd2kfd_unlock_kfd();
> }
> +
> +
> +u64 amdgpu_amdkfd_xcp_memory_size(struct amdgpu_device *adev, int xcp_id)
> +{
> + u64 tmp;
> +
> + if (adev->gmc.num_mem_partitions && xcp_id >= 0) {
> + tmp = adev->gmc.mem_partitions[KFD_XCP_MEM_ID(adev, xcp_id)].size;
> + do_div(tmp, adev->xcp_mgr->num_xcp_per_mem_partition);
> + return tmp;
> + } else {
> + return adev->gmc.real_vram_size;
> + }
> +}
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h
> index be43d71ba7ef..94cc456761e5 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h
> @@ -333,15 +333,14 @@ int amdgpu_amdkfd_reserve_mem_limit(struct amdgpu_device *adev,
> void amdgpu_amdkfd_unreserve_mem_limit(struct amdgpu_device *adev,
> uint64_t size, u32 alloc_flag, int8_t xcp_id);
>
> +u64 amdgpu_amdkfd_xcp_memory_size(struct amdgpu_device *adev, int xcp_id);
> +
> #define KFD_XCP_MEM_ID(adev, xcp_id) \
> ((adev)->xcp_mgr && (xcp_id) >= 0 ?\
> (adev)->xcp_mgr->xcp[(xcp_id)].mem_id : -1)
>
> -#define KFD_XCP_MEMORY_SIZE(adev, xcp_id)\
> - ((adev)->gmc.num_mem_partitions && (xcp_id) >= 0 ?\
> - (adev)->gmc.mem_partitions[KFD_XCP_MEM_ID((adev), (xcp_id))].size /\
> - (adev)->xcp_mgr->num_xcp_per_mem_partition :\
> - (adev)->gmc.real_vram_size)
> +#define KFD_XCP_MEMORY_SIZE(adev, xcp_id) amdgpu_amdkfd_xcp_memory_size((adev), (xcp_id))
> +
>
> #if IS_ENABLED(CONFIG_HSA_AMD)
> void amdgpu_amdkfd_gpuvm_init_mem_limits(void);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> index ad664ef640ff..34724b771ace 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> @@ -818,11 +818,14 @@ static void amdgpu_ttm_gart_bind_gfx9_mqd(struct amdgpu_device *adev,
> struct amdgpu_ttm_tt *gtt = (void *)ttm;
> uint64_t total_pages = ttm->num_pages;
> int num_xcc = max(1U, adev->gfx.num_xcc_per_xcp);
> - uint64_t page_idx, pages_per_xcc = total_pages / num_xcc;
> + uint64_t page_idx, pages_per_xcc;
> int i;
> uint64_t ctrl_flags = (flags & ~AMDGPU_PTE_MTYPE_VG10_MASK) |
> AMDGPU_PTE_MTYPE_VG10(AMDGPU_MTYPE_NC);
>
> + pages_per_xcc = total_pages;
> + do_div(pages_per_xcc, num_xcc);
> +
> for (i = 0, page_idx = 0; i < num_xcc; i++, page_idx += pages_per_xcc) {
> /* MQD page: use default flags */
> amdgpu_gart_bind(adev,
> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> index 938c8dba9057..d559e7bc0f09 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> @@ -1919,9 +1919,10 @@ gmc_v9_0_init_acpi_mem_ranges(struct amdgpu_device *adev,
> adev->gmc.num_mem_partitions = num_ranges;
>
> /* If there is only partition, don't use entire size */
> - if (adev->gmc.num_mem_partitions == 1)
> - mem_ranges[0].size =
> - (mem_ranges[0].size * (mem_groups - 1) / mem_groups);
> + if (adev->gmc.num_mem_partitions == 1) {
> + mem_ranges[0].size = mem_ranges[0].size * (mem_groups - 1);
> + do_div(mem_ranges[0].size, mem_groups);
> + }
> }
>
> static void
> @@ -1953,8 +1954,8 @@ gmc_v9_0_init_sw_mem_ranges(struct amdgpu_device *adev,
> break;
> }
>
> - size = (adev->gmc.real_vram_size >> AMDGPU_GPU_PAGE_SHIFT) /
> - adev->gmc.num_mem_partitions;
> + size = adev->gmc.real_vram_size >> AMDGPU_GPU_PAGE_SHIFT;
> + size /= adev->gmc.num_mem_partitions;
>
> Did you miss using the do_div() here?
It's not needed here. size is 32 bits IIRC.
Alex
>
> Thanks,
> Mukul
>
> for (i = 0; i < adev->gmc.num_mem_partitions; ++i) {
> mem_ranges[i].range.fpfn = start_addr;
> --
> 2.40.1
>
