drm/amdgpu: fix incorrect active rb bitmap for gfx11

GFX v11 changes RB_BACKEND_DISABLE related registers
from per SA to global ones. The approach to query active
rb bitmap needs to be changed accordingly. Query per
SE setting returns wrong active RB bitmap especially
in the case when some of SA are disabled. With the new
approach, driver will generate the active rb bitmap
based on active SA bitmap and global active RB bitmap.

Signed-off-by: Hawking Zhang <Hawking.Zhang@amd.com>
Reviewed-by: Likun Gao <Likun.Gao@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c

@@ -1503,44 +1503,70 @@ static void gfx_v11_0_select_se_sh(struct amdgpu_device *adev, u32 se_num,
 	WREG32_SOC15(GC, 0, regGRBM_GFX_INDEX, data);
 }
 
-static u32 gfx_v11_0_get_rb_active_bitmap(struct amdgpu_device *adev)
+static u32 gfx_v11_0_get_sa_active_bitmap(struct amdgpu_device *adev)
 {
-	u32 data, mask;
+	u32 gc_disabled_sa_mask, gc_user_disabled_sa_mask, sa_mask;
+
+	gc_disabled_sa_mask = RREG32_SOC15(GC, 0, regCC_GC_SA_UNIT_DISABLE);
+	gc_disabled_sa_mask = REG_GET_FIELD(gc_disabled_sa_mask,
+					   CC_GC_SA_UNIT_DISABLE,
+					   SA_DISABLE);
+	gc_user_disabled_sa_mask = RREG32_SOC15(GC, 0, regGC_USER_SA_UNIT_DISABLE);
+	gc_user_disabled_sa_mask = REG_GET_FIELD(gc_user_disabled_sa_mask,
+						 GC_USER_SA_UNIT_DISABLE,
+						 SA_DISABLE);
+	sa_mask = amdgpu_gfx_create_bitmask(adev->gfx.config.max_sh_per_se *
+					    adev->gfx.config.max_shader_engines);
 
-	data = RREG32_SOC15(GC, 0, regCC_RB_BACKEND_DISABLE);
-	data |= RREG32_SOC15(GC, 0, regGC_USER_RB_BACKEND_DISABLE);
+	return sa_mask & (~(gc_disabled_sa_mask | gc_user_disabled_sa_mask));
+}
 
-	data &= CC_RB_BACKEND_DISABLE__BACKEND_DISABLE_MASK;
-	data >>= GC_USER_RB_BACKEND_DISABLE__BACKEND_DISABLE__SHIFT;
+static u32 gfx_v11_0_get_rb_active_bitmap(struct amdgpu_device *adev)
+{
+	u32 gc_disabled_rb_mask, gc_user_disabled_rb_mask;
+	u32 rb_mask;
 
-	mask = amdgpu_gfx_create_bitmask(adev->gfx.config.max_backends_per_se /
-					 adev->gfx.config.max_sh_per_se);
+	gc_disabled_rb_mask = RREG32_SOC15(GC, 0, regCC_RB_BACKEND_DISABLE);
+	gc_disabled_rb_mask = REG_GET_FIELD(gc_disabled_rb_mask,
+					    CC_RB_BACKEND_DISABLE,
+					    BACKEND_DISABLE);
+	gc_user_disabled_rb_mask = RREG32_SOC15(GC, 0, regGC_USER_RB_BACKEND_DISABLE);
+	gc_user_disabled_rb_mask = REG_GET_FIELD(gc_user_disabled_rb_mask,
+						 GC_USER_RB_BACKEND_DISABLE,
+						 BACKEND_DISABLE);
+	rb_mask = amdgpu_gfx_create_bitmask(adev->gfx.config.max_backends_per_se *
+					    adev->gfx.config.max_shader_engines);
 
-	return (~data) & mask;
+	return rb_mask & (~(gc_disabled_rb_mask | gc_user_disabled_rb_mask));
 }
 
 static void gfx_v11_0_setup_rb(struct amdgpu_device *adev)
 {
-	int i, j;
-	u32 data;
-	u32 active_rbs = 0;
-	u32 rb_bitmap_width_per_sh = adev->gfx.config.max_backends_per_se /
-					adev->gfx.config.max_sh_per_se;
+	u32 rb_bitmap_width_per_sa;
+	u32 max_sa;
+	u32 active_sa_bitmap;
+	u32 global_active_rb_bitmap;
+	u32 active_rb_bitmap = 0;
+	u32 i;
 
-	mutex_lock(&adev->grbm_idx_mutex);
-	for (i = 0; i < adev->gfx.config.max_shader_engines; i++) {
-		for (j = 0; j < adev->gfx.config.max_sh_per_se; j++) {
-			gfx_v11_0_select_se_sh(adev, i, j, 0xffffffff);
-			data = gfx_v11_0_get_rb_active_bitmap(adev);
-			active_rbs |= data << ((i * adev->gfx.config.max_sh_per_se + j) *
-					       rb_bitmap_width_per_sh);
-		}
+	/* query sa bitmap from SA_UNIT_DISABLE registers */
+	active_sa_bitmap = gfx_v11_0_get_sa_active_bitmap(adev);
+	/* query rb bitmap from RB_BACKEND_DISABLE registers */
+	global_active_rb_bitmap = gfx_v11_0_get_rb_active_bitmap(adev);
+
+	/* generate active rb bitmap according to active sa bitmap */
+	max_sa = adev->gfx.config.max_shader_engines *
+		 adev->gfx.config.max_sh_per_se;
+	rb_bitmap_width_per_sa = adev->gfx.config.max_backends_per_se /
+				 adev->gfx.config.max_sh_per_se;
+	for (i = 0; i < max_sa; i++) {
+		if (active_sa_bitmap & (1 << i))
+			active_rb_bitmap |= (0x3 << (i * rb_bitmap_width_per_sa));
 	}
-	gfx_v11_0_select_se_sh(adev, 0xffffffff, 0xffffffff, 0xffffffff);
-	mutex_unlock(&adev->grbm_idx_mutex);
 
-	adev->gfx.config.backend_enable_mask = active_rbs;
-	adev->gfx.config.num_rbs = hweight32(active_rbs);
+	active_rb_bitmap |= global_active_rb_bitmap;
+	adev->gfx.config.backend_enable_mask = active_rb_bitmap;
+	adev->gfx.config.num_rbs = hweight32(active_rb_bitmap);
 }
 
 #define DEFAULT_SH_MEM_BASES	(0x6000)