drm/amdgpu/virt: use kiq to access registers (v2)

For virtualization, it is must for driver to use KIQ to access
registers when it is out of GPU full access mode.

v2: agd: rebase
Signed-off-by: Xiangliang Yu <Xiangliang.Yu@amd.com>
Signed-off-by: Monk Liu <Monk.Liu@amd.com>
Reviewed-by: Monk Liu <Monk.Liu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c

@@ -94,6 +94,11 @@ uint32_t amdgpu_mm_rreg(struct amdgpu_device *adev, uint32_t reg,
 {
 	uint32_t ret;
 
+	if (amdgpu_sriov_runtime(adev)) {
+		BUG_ON(in_interrupt());
+		return amdgpu_virt_kiq_rreg(adev, reg);
+	}
+
 	if ((reg * 4) < adev->rmmio_size && !always_indirect)
 		ret = readl(((void __iomem *)adev->rmmio) + (reg * 4));
 	else {
@@ -113,6 +118,11 @@ void amdgpu_mm_wreg(struct amdgpu_device *adev, uint32_t reg, uint32_t v,
 {
 	trace_amdgpu_mm_wreg(adev->pdev->device, reg, v);
 
+	if (amdgpu_sriov_runtime(adev)) {
+		BUG_ON(in_interrupt());
+		return amdgpu_virt_kiq_wreg(adev, reg, v);
+	}
+
 	if ((reg * 4) < adev->rmmio_size && !always_indirect)
 		writel(v, ((void __iomem *)adev->rmmio) + (reg * 4));
 	else {

drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c

@@ -91,3 +91,61 @@ int amdgpu_map_static_csa(struct amdgpu_device *adev, struct amdgpu_vm *vm)
 	ttm_eu_backoff_reservation(&ticket, &list);
 	return 0;
 }
+
+void amdgpu_virt_init_setting(struct amdgpu_device *adev)
+{
+	mutex_init(&adev->virt.lock);
+}
+
+uint32_t amdgpu_virt_kiq_rreg(struct amdgpu_device *adev, uint32_t reg)
+{
+	signed long r;
+	uint32_t val;
+	struct dma_fence *f;
+	struct amdgpu_kiq *kiq = &adev->gfx.kiq;
+	struct amdgpu_ring *ring = &kiq->ring;
+
+	BUG_ON(!ring->funcs->emit_rreg);
+
+	mutex_lock(&adev->virt.lock);
+	amdgpu_ring_alloc(ring, 32);
+	amdgpu_ring_emit_hdp_flush(ring);
+	amdgpu_ring_emit_rreg(ring, reg);
+	amdgpu_ring_emit_hdp_invalidate(ring);
+	amdgpu_fence_emit(ring, &f);
+	amdgpu_ring_commit(ring);
+	mutex_unlock(&adev->virt.lock);
+
+	r = dma_fence_wait(f, false);
+	if (r)
+		DRM_ERROR("wait for kiq fence error: %ld.\n", r);
+	dma_fence_put(f);
+
+	val = adev->wb.wb[adev->virt.reg_val_offs];
+
+	return val;
+}
+
+void amdgpu_virt_kiq_wreg(struct amdgpu_device *adev, uint32_t reg, uint32_t v)
+{
+	signed long r;
+	struct dma_fence *f;
+	struct amdgpu_kiq *kiq = &adev->gfx.kiq;
+	struct amdgpu_ring *ring = &kiq->ring;
+
+	BUG_ON(!ring->funcs->emit_wreg);
+
+	mutex_lock(&adev->virt.lock);
+	amdgpu_ring_alloc(ring, 32);
+	amdgpu_ring_emit_hdp_flush(ring);
+	amdgpu_ring_emit_wreg(ring, reg, v);
+	amdgpu_ring_emit_hdp_invalidate(ring);
+	amdgpu_fence_emit(ring, &f);
+	amdgpu_ring_commit(ring);
+	mutex_unlock(&adev->virt.lock);
+
+	r = dma_fence_wait(f, false);
+	if (r)
+		DRM_ERROR("wait for kiq fence error: %ld.\n", r);
+	dma_fence_put(f);
+}

drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h

@@ -36,6 +36,7 @@ struct amdgpu_virt {
 	struct amdgpu_bo *csa_obj;
 	uint64_t csa_vmid0_addr;
 	uint32_t		reg_val_offs;
+	struct mutex		lock;
 };
 
 #define AMDGPU_CSA_SIZE    (8 * 1024)
@@ -68,5 +69,8 @@ static inline bool is_virtual_machine(void)
 struct amdgpu_vm;
 int amdgpu_allocate_static_csa(struct amdgpu_device *adev);
 int amdgpu_map_static_csa(struct amdgpu_device *adev, struct amdgpu_vm *vm);
+void amdgpu_virt_init_setting(struct amdgpu_device *adev);
+uint32_t amdgpu_virt_kiq_rreg(struct amdgpu_device *adev, uint32_t reg);
+void amdgpu_virt_kiq_wreg(struct amdgpu_device *adev, uint32_t reg, uint32_t v);
 
 #endif

drivers/gpu/drm/amd/amdgpu/vi.c

@@ -921,6 +921,9 @@ static int vi_common_early_init(void *handle)
 		(amdgpu_ip_block_mask & (1 << AMD_IP_BLOCK_TYPE_SMC)))
 		smc_enabled = true;
 
+	if (amdgpu_sriov_vf(adev))
+		amdgpu_virt_init_setting(adev);
+
 	adev->rev_id = vi_get_rev_id(adev);
 	adev->external_rev_id = 0xFF;
 	switch (adev->asic_type) {