[PATCH v2] drm/amdgpu: Unify Device Aperture in amdgpu_info_ioctl for KGD/KFD
Alex Deucher
alexdeucher at gmail.com
Tue Jul 1 14:07:19 UTC 2025
On Tue, Jul 1, 2025 at 2:53 AM Srinivasan Shanmugam
<srinivasan.shanmugam at amd.com> wrote:
>
> This commit refines the amdgpu_info_ioctl function to unify
> the reporting of device apertures for both KGD and KFD
> subsystems.
>
> v2:
> - Use amdgpu_ip_version() instead of directly accessing
> adev->ip_versions. (Alex)
> - Added AMDGPU_VM_ prefix to scratch and LDS base and limit macros.
> (Christian)
> - Clarified in comments that the top 16 bits of the 64-bit address must
> not be 0x0000 or 0xffff to avoid sign extension problems. (Christian)
>
> Cc: David Yat Sin <David.YatSin at amd.com>
> Cc: Christian König <christian.koenig at amd.com>
> Cc: Alex Deucher <alexander.deucher at amd.com>
> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam at amd.com>
Reviewed-by: Alex Deucher <alexander.deucher at amd.com>
But don't commit this yet as we are still waiting on the userspace
side to be complete.
Alex
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 25 +++++++++++
> drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h | 23 ++++++++++
> drivers/gpu/drm/amd/amdkfd/kfd_flat_memory.c | 45 ++++----------------
> include/uapi/drm/amdgpu_drm.h | 6 +++
> 4 files changed, 62 insertions(+), 37 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> index 4aab5e394ce2..76d902342271 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> @@ -46,6 +46,7 @@
> #include "amdgpu_reset.h"
> #include "amd_pcie.h"
> #include "amdgpu_userq.h"
> +#include "amdgpu_vm.h"
>
> void amdgpu_unregister_gpu_instance(struct amdgpu_device *adev)
> {
> @@ -1031,6 +1032,30 @@ int amdgpu_info_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
>
> dev_info->userq_ip_mask = amdgpu_userq_get_supported_ip_mask(adev);
>
> + /* Retrieve Device Apertures */
> + if (amdgpu_ip_version(adev, GC_HWIP, 0) >= IP_VERSION(9, 0, 0)) {
> + dev_info->lds_base = AMDGPU_VM_MAKE_LDS_APP_BASE_V9();
> + dev_info->scratch_base = AMDGPU_VM_MAKE_SCRATCH_APP_BASE_V9();
> +
> + dev_info->lds_limit = AMDGPU_VM_MAKE_LDS_APP_LIMIT(dev_info->lds_base);
> + dev_info->scratch_limit =
> + AMDGPU_VM_MAKE_SCRATCH_APP_LIMIT(dev_info->scratch_base);
> + } else {
> + dev_info->lds_base = AMDGPU_VM_MAKE_LDS_APP_BASE_VI();
> + dev_info->scratch_base = AMDGPU_VM_MAKE_SCRATCH_APP_BASE_VI();
> +
> + dev_info->lds_limit = AMDGPU_VM_MAKE_LDS_APP_LIMIT(dev_info->lds_base);
> + dev_info->scratch_limit =
> + AMDGPU_VM_MAKE_SCRATCH_APP_LIMIT(dev_info->scratch_base);
> + }
> +
> + dev_dbg(adev->dev, "Node ID: %u\n", adev->dev->id);
> + dev_dbg(adev->dev, "GPU ID: %u\n", dev_info->device_id);
> + dev_dbg(adev->dev, "LDS Base: %llX\n", dev_info->lds_base);
> + dev_dbg(adev->dev, "LDS Limit: %llX\n", dev_info->lds_limit);
> + dev_dbg(adev->dev, "Scratch Base: %llX\n", dev_info->scratch_base);
> + dev_dbg(adev->dev, "Scratch Limit: %llX\n", dev_info->scratch_limit);
> +
> ret = copy_to_user(out, dev_info,
> min((size_t)size, sizeof(*dev_info))) ? -EFAULT : 0;
> kfree(dev_info);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
> index f3ad687125ad..fd8f6da30096 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
> @@ -184,6 +184,29 @@ struct amdgpu_bo_vm;
> #define AMDGPU_VM_USE_CPU_FOR_GFX (1 << 0)
> #define AMDGPU_VM_USE_CPU_FOR_COMPUTE (1 << 1)
>
> +#define AMDGPU_VM_MAKE_SCRATCH_APP_BASE_VI() \
> + (((uint64_t)(0x1UL) << 61) + 0x100000000L)
> +#define AMDGPU_VM_MAKE_SCRATCH_APP_LIMIT(base) \
> + (((uint64_t)(base) & 0xFFFFFFFF00000000UL) | 0xFFFFFFFF)
> +
> +#define AMDGPU_VM_MAKE_LDS_APP_BASE_VI() \
> + (((uint64_t)(0x1UL) << 61) + 0x0)
> +#define AMDGPU_VM_MAKE_LDS_APP_LIMIT(base) \
> + (((uint64_t)(base) & 0xFFFFFFFF00000000UL) | 0xFFFFFFFF)
> +
> +/* On GFXv9 the LDS and scratch apertures are programmed independently
> + * using the high 16 bits of the 64-bit virtual address. They must be
> + * in the hole, which will be the case as long as the high 16 bits are
> + * neither 0x0000 nor 0xffff to avoid sign extension issues.
> + *
> + * The aperture sizes are still 4GB implicitly.
> + *
> + * Note: While GPUVM apertures are generally not applicable on GFXv9,
> + * there is at least one APU case where GFX9 has a limited GPUVM aperture.
> + */
> +#define AMDGPU_VM_MAKE_LDS_APP_BASE_V9() ((uint64_t)(0x1UL) << 48)
> +#define AMDGPU_VM_MAKE_SCRATCH_APP_BASE_V9() ((uint64_t)(0x2UL) << 48)
> +
> /* VMPT level enumerate, and the hiberachy is:
> * PDB2->PDB1->PDB0->PTB
> */
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_flat_memory.c b/drivers/gpu/drm/amd/amdkfd/kfd_flat_memory.c
> index 1d170dc50df3..291b068aaf8a 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_flat_memory.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_flat_memory.c
> @@ -276,35 +276,6 @@
> * for FLAT_* / S_LOAD operations.
> */
>
> -#define MAKE_GPUVM_APP_BASE_VI(gpu_num) \
> - (((uint64_t)(gpu_num) << 61) + 0x1000000000000L)
> -
> -#define MAKE_GPUVM_APP_LIMIT(base, size) \
> - (((uint64_t)(base) & 0xFFFFFF0000000000UL) + (size) - 1)
> -
> -#define MAKE_SCRATCH_APP_BASE_VI() \
> - (((uint64_t)(0x1UL) << 61) + 0x100000000L)
> -
> -#define MAKE_SCRATCH_APP_LIMIT(base) \
> - (((uint64_t)base & 0xFFFFFFFF00000000UL) | 0xFFFFFFFF)
> -
> -#define MAKE_LDS_APP_BASE_VI() \
> - (((uint64_t)(0x1UL) << 61) + 0x0)
> -#define MAKE_LDS_APP_LIMIT(base) \
> - (((uint64_t)(base) & 0xFFFFFFFF00000000UL) | 0xFFFFFFFF)
> -
> -/* On GFXv9 the LDS and scratch apertures are programmed independently
> - * using the high 16 bits of the 64-bit virtual address. They must be
> - * in the hole, which will be the case as long as the high 16 bits are
> - * not 0.
> - *
> - * The aperture sizes are still 4GB implicitly.
> - *
> - * A GPUVM aperture is not applicable on GFXv9.
> - */
> -#define MAKE_LDS_APP_BASE_V9() ((uint64_t)(0x1UL) << 48)
> -#define MAKE_SCRATCH_APP_BASE_V9() ((uint64_t)(0x2UL) << 48)
> -
> /* User mode manages most of the SVM aperture address space. The low
> * 16MB are reserved for kernel use (CWSR trap handler and kernel IB
> * for now).
> @@ -319,8 +290,8 @@ static void kfd_init_apertures_vi(struct kfd_process_device *pdd, uint8_t id)
> * node id couldn't be 0 - the three MSB bits of
> * aperture shouldn't be 0
> */
> - pdd->lds_base = MAKE_LDS_APP_BASE_VI();
> - pdd->lds_limit = MAKE_LDS_APP_LIMIT(pdd->lds_base);
> + pdd->lds_base = AMDGPU_VM_MAKE_LDS_APP_BASE_VI();
> + pdd->lds_limit = AMDGPU_VM_MAKE_LDS_APP_LIMIT(pdd->lds_base);
>
> /* dGPUs: SVM aperture starting at 0
> * with small reserved space for kernel.
> @@ -336,21 +307,21 @@ static void kfd_init_apertures_vi(struct kfd_process_device *pdd, uint8_t id)
> pdd->qpd.cwsr_base = SVM_CWSR_BASE;
> pdd->qpd.ib_base = SVM_IB_BASE;
>
> - pdd->scratch_base = MAKE_SCRATCH_APP_BASE_VI();
> - pdd->scratch_limit = MAKE_SCRATCH_APP_LIMIT(pdd->scratch_base);
> + pdd->scratch_base = AMDGPU_VM_MAKE_SCRATCH_APP_BASE_VI();
> + pdd->scratch_limit = AMDGPU_VM_MAKE_SCRATCH_APP_LIMIT(pdd->scratch_base);
> }
>
> static void kfd_init_apertures_v9(struct kfd_process_device *pdd, uint8_t id)
> {
> - pdd->lds_base = MAKE_LDS_APP_BASE_V9();
> - pdd->lds_limit = MAKE_LDS_APP_LIMIT(pdd->lds_base);
> + pdd->lds_base = AMDGPU_VM_MAKE_LDS_APP_BASE_V9();
> + pdd->lds_limit = AMDGPU_VM_MAKE_LDS_APP_LIMIT(pdd->lds_base);
>
> pdd->gpuvm_base = AMDGPU_VA_RESERVED_BOTTOM;
> pdd->gpuvm_limit =
> pdd->dev->kfd->shared_resources.gpuvm_size - 1;
>
> - pdd->scratch_base = MAKE_SCRATCH_APP_BASE_V9();
> - pdd->scratch_limit = MAKE_SCRATCH_APP_LIMIT(pdd->scratch_base);
> + pdd->scratch_base = AMDGPU_VM_MAKE_SCRATCH_APP_BASE_V9();
> + pdd->scratch_limit = AMDGPU_VM_MAKE_SCRATCH_APP_LIMIT(pdd->scratch_base);
>
> /*
> * Place TBA/TMA on opposite side of VM hole to prevent
> diff --git a/include/uapi/drm/amdgpu_drm.h b/include/uapi/drm/amdgpu_drm.h
> index 66c4a03ac9f9..f285e9325d06 100644
> --- a/include/uapi/drm/amdgpu_drm.h
> +++ b/include/uapi/drm/amdgpu_drm.h
> @@ -1477,6 +1477,12 @@ struct drm_amdgpu_info_device {
> /* Userq IP mask (1 << AMDGPU_HW_IP_*) */
> __u32 userq_ip_mask;
> __u32 pad;
> +
> + /* Additional fields for memory aperture information */
> + __u64 lds_base; /* LDS base */
> + __u64 lds_limit; /* LDS limit */
> + __u64 scratch_base; /* Scratch base */
> + __u64 scratch_limit; /* Scratch limit */
> };
>
> struct drm_amdgpu_info_hw_ip {
> --
> 2.34.1
>
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