Add VM update mode module param (amdgpu.vm_update_mode) that can used to
control how VM pde/pte are updated for Graphics and Compute.
BIT0 controls Graphics and BIT1 Compute.
BIT0 [= 0] Graphics updated by SDMA [= 1] by CPU
BIT1 [= 0] Compute updated by SDMA [= 1] by CPU
By default, only for large BAR system vm_update_mode = 2, indicating
that Graphics VMs will be updated via SDMA and Compute VMs will be
updated via CPU. And for all all other systems (by default)
vm_update_mode = 0
Signed-off-by: Harish Kasiviswanathan <Harish.Kasiviswanathan at amd.com>
---
drivers/gpu/drm/amd/amdgpu/amdgpu.h | 1 +
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 4 ++++
drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 3 ++-
drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 35 ++++++++++++++++++++++++++++++++-
drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h | 20 ++++++++++++++++++-
5 files changed, 60 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index fadeb55..fd84410 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -94,6 +94,7 @@
extern int amdgpu_vm_block_size;
extern int amdgpu_vm_fault_stop;
extern int amdgpu_vm_debug;
+extern int amdgpu_vm_update_mode;
extern int amdgpu_dc;
extern int amdgpu_sched_jobs;
extern int amdgpu_sched_hw_submission;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index 130c45d..8d28a35 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -94,6 +94,7 @@
int amdgpu_vm_fault_stop = 0;
int amdgpu_vm_debug = 0;
int amdgpu_vram_page_split = 512;
+int amdgpu_vm_update_mode = -1;
int amdgpu_exp_hw_support = 0;
int amdgpu_dc = -1;
int amdgpu_sched_jobs = 32;
@@ -180,6 +181,9 @@
MODULE_PARM_DESC(vm_debug, "Debug VM handling (0 = disabled (default), 1 = enabled)");
module_param_named(vm_debug, amdgpu_vm_debug, int, 0644);
+MODULE_PARM_DESC(vm_update_mode, "VM update using CPU (0 = never (default except for large BAR(LB)), 1 = Graphics only, 2 = Compute only (default for LB), 3 = Both");
+module_param_named(vm_update_mode, amdgpu_vm_update_mode, int, 0444);
+
MODULE_PARM_DESC(vram_page_split, "Number of pages after we split VRAM allocations (default 1024, -1 = disable)");
module_param_named(vram_page_split, amdgpu_vram_page_split, int, 0444);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
index d167949..8f6c20f 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
@@ -774,7 +774,8 @@ int amdgpu_driver_open_kms(struct drm_device *dev, struct drm_file *file_priv)
goto out_suspend;
}
- r = amdgpu_vm_init(adev, &fpriv->vm);
+ r = amdgpu_vm_init(adev, &fpriv->vm,
+ AMDGPU_VM_CONTEXT_GFX);
if (r) {
kfree(fpriv);
goto out_suspend;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index c644e54..9c89cb2 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -721,6 +721,11 @@ bool amdgpu_vm_need_pipeline_sync(struct amdgpu_ring *ring,
return true;
}
+static bool amdgpu_vm_is_large_bar(struct amdgpu_device *adev)
+{
+ return (adev->mc.real_vram_size == adev->mc.visible_vram_size);
+}
+
/**
* amdgpu_vm_flush - hardware flush the vm
*
@@ -2291,10 +2296,12 @@ void amdgpu_vm_adjust_size(struct amdgpu_device *adev, uint64_t vm_size)
*
* @adev: amdgpu_device pointer
* @vm: requested vm
+ * @vm_context: Indicates if it GFX or Compute context
*
* Init @vm fields.
*/
-int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm)
+int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm,
+ int vm_context)
{
const unsigned align = min(AMDGPU_VM_PTB_ALIGN_SIZE,
AMDGPU_VM_PTE_COUNT(adev) * 8);
@@ -2323,6 +2330,16 @@ int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm)
if (r)
return r;
+ if (vm_context == AMDGPU_VM_CONTEXT_COMPUTE)
+ vm->use_cpu_for_update = !!(adev->vm_manager.vm_update_mode &
+ AMDGPU_VM_USE_CPU_FOR_COMPUTE);
+ else
+ vm->use_cpu_for_update = !!(adev->vm_manager.vm_update_mode &
+ AMDGPU_VM_USE_CPU_FOR_GFX);
+ DRM_DEBUG_DRIVER("VM update mode is %s\n",
+ vm->use_cpu_for_update ? "CPU" : "SDMA");
+ WARN_ONCE((vm->use_cpu_for_update & !amdgpu_vm_is_large_bar(adev)),
+ "CPU update of VM recommended only for large BAR system\n");
vm->last_dir_update = NULL;
r = amdgpu_bo_create(adev, amdgpu_vm_bo_size(adev, 0), align, true,
@@ -2454,6 +2471,22 @@ void amdgpu_vm_manager_init(struct amdgpu_device *adev)
atomic64_set(&adev->vm_manager.client_counter, 0);
spin_lock_init(&adev->vm_manager.prt_lock);
atomic_set(&adev->vm_manager.num_prt_users, 0);
+
+ /* If not overridden by the user, by default, only in large BAR systems
+ * Compute VM tables will be updated by CPU
+ */
+#ifdef CONFIG_X86_64
+ if (amdgpu_vm_update_mode == -1) {
+ if (amdgpu_vm_is_large_bar(adev))
+ adev->vm_manager.vm_update_mode =
+ AMDGPU_VM_USE_CPU_FOR_COMPUTE;
+ else
+ adev->vm_manager.vm_update_mode = 0;
+ }
+#else
+ adev->vm_manager.vm_update_mode = 0;
+#endif
+
}
/**
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
index afe9073..9aa00d9 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
@@ -87,6 +87,14 @@
/* max vmids dedicated for process */
#define AMDGPU_VM_MAX_RESERVED_VMID 1
+#define AMDGPU_VM_CONTEXT_GFX 0
+#define AMDGPU_VM_CONTEXT_COMPUTE 1
+
+/* See vm_update_mode */
+#define AMDGPU_VM_USE_CPU_FOR_GFX (1 << 0)
+#define AMDGPU_VM_USE_CPU_FOR_COMPUTE (1 << 1)
+
+
struct amdgpu_vm_pt {
struct amdgpu_bo *bo;
uint64_t addr;
@@ -129,6 +137,9 @@ struct amdgpu_vm {
struct amdgpu_vm_id *reserved_vmid[AMDGPU_MAX_VMHUBS];
/* each VM will map on CSA */
struct amdgpu_bo_va *csa_bo_va;
+
+ /* Flag to indicate if VM tables are updated by CPU or GPU (SDMA) */
+ bool use_cpu_for_update;
};
struct amdgpu_vm_id {
@@ -184,11 +195,18 @@ struct amdgpu_vm_manager {
/* partial resident texture handling */
spinlock_t prt_lock;
atomic_t num_prt_users;
+
+ /* controls how VM page tables are updated for Graphics and Compute.
+ * BIT0[= 0] Graphics updated by SDMA [= 1] by CPU
+ * BIT1[= 0] Compute updated by SDMA [= 1] by CPU
+ */
+ int vm_update_mode;
};
void amdgpu_vm_manager_init(struct amdgpu_device *adev);
void amdgpu_vm_manager_fini(struct amdgpu_device *adev);
-int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm);
+int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm,
+ int vm_context);
void amdgpu_vm_fini(struct amdgpu_device *adev, struct amdgpu_vm *vm);
void amdgpu_vm_get_pd_bo(struct amdgpu_vm *vm,
struct list_head *validated,
--
1.9.1
