drm/radeon: properly handle mc_stop/mc_resume on evergreen+ (v2)

commit 62444b74 upstream.

- Stop the displays from accessing the FB
- Block CPU access
- Turn off MC client access

This should fix issues some users have seen, especially
with UEFI, when changing the MC FB location that result
in hangs or display corruption.

v2: fix crtc enabled check noticed by Luca Tettamanti
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[bwh: Backported to 3.2:
 - Drop DCE6 cases
 - Call evergreen_mc_wait_for_idle() directly
 - Add dce4_wait_for_vblank() (commits 3ae19b75
   and 4a15903d) and call it directly
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/gpu/drm/radeon/evergreen.c

@@ -37,6 +37,16 @@
 #define EVERGREEN_PFP_UCODE_SIZE 1120
 #define EVERGREEN_PM4_UCODE_SIZE 1376
 
+static const u32 crtc_offsets[6] =
+{
+	EVERGREEN_CRTC0_REGISTER_OFFSET,
+	EVERGREEN_CRTC1_REGISTER_OFFSET,
+	EVERGREEN_CRTC2_REGISTER_OFFSET,
+	EVERGREEN_CRTC3_REGISTER_OFFSET,
+	EVERGREEN_CRTC4_REGISTER_OFFSET,
+	EVERGREEN_CRTC5_REGISTER_OFFSET
+};
+
 static void evergreen_gpu_init(struct radeon_device *rdev);
 void evergreen_fini(struct radeon_device *rdev);
 void evergreen_pcie_gen2_enable(struct radeon_device *rdev);
@@ -66,6 +76,27 @@ void evergreen_fix_pci_max_read_req_size(struct radeon_device *rdev)
 	}
 }
 
+void dce4_wait_for_vblank(struct radeon_device *rdev, int crtc)
+{
+	int i;
+
+	if (crtc >= rdev->num_crtc)
+		return;
+
+	if (RREG32(EVERGREEN_CRTC_CONTROL + crtc_offsets[crtc]) & EVERGREEN_CRTC_MASTER_EN) {
+		for (i = 0; i < rdev->usec_timeout; i++) {
+			if (!(RREG32(EVERGREEN_CRTC_STATUS + crtc_offsets[crtc]) & EVERGREEN_CRTC_V_BLANK))
+				break;
+			udelay(1);
+		}
+		for (i = 0; i < rdev->usec_timeout; i++) {
+			if (RREG32(EVERGREEN_CRTC_STATUS + crtc_offsets[crtc]) & EVERGREEN_CRTC_V_BLANK)
+				break;
+			udelay(1);
+		}
+	}
+}
+
 void evergreen_pre_page_flip(struct radeon_device *rdev, int crtc)
 {
 	/* enable the pflip int */
@@ -1065,116 +1096,88 @@ void evergreen_agp_enable(struct radeon_device *rdev)
 
 void evergreen_mc_stop(struct radeon_device *rdev, struct evergreen_mc_save *save)
 {
+	u32 crtc_enabled, tmp, frame_count, blackout;
+	int i, j;
+
 	save->vga_render_control = RREG32(VGA_RENDER_CONTROL);
 	save->vga_hdp_control = RREG32(VGA_HDP_CONTROL);
 
-	/* Stop all video */
+	/* disable VGA render */
 	WREG32(VGA_RENDER_CONTROL, 0);
-	WREG32(EVERGREEN_CRTC_UPDATE_LOCK + EVERGREEN_CRTC0_REGISTER_OFFSET, 1);
-	WREG32(EVERGREEN_CRTC_UPDATE_LOCK + EVERGREEN_CRTC1_REGISTER_OFFSET, 1);
-	if (rdev->num_crtc >= 4) {
-		WREG32(EVERGREEN_CRTC_UPDATE_LOCK + EVERGREEN_CRTC2_REGISTER_OFFSET, 1);
-		WREG32(EVERGREEN_CRTC_UPDATE_LOCK + EVERGREEN_CRTC3_REGISTER_OFFSET, 1);
-	}
-	if (rdev->num_crtc >= 6) {
-		WREG32(EVERGREEN_CRTC_UPDATE_LOCK + EVERGREEN_CRTC4_REGISTER_OFFSET, 1);
-		WREG32(EVERGREEN_CRTC_UPDATE_LOCK + EVERGREEN_CRTC5_REGISTER_OFFSET, 1);
-	}
-	WREG32(EVERGREEN_CRTC_CONTROL + EVERGREEN_CRTC0_REGISTER_OFFSET, 0);
-	WREG32(EVERGREEN_CRTC_CONTROL + EVERGREEN_CRTC1_REGISTER_OFFSET, 0);
-	if (rdev->num_crtc >= 4) {
-		WREG32(EVERGREEN_CRTC_CONTROL + EVERGREEN_CRTC2_REGISTER_OFFSET, 0);
-		WREG32(EVERGREEN_CRTC_CONTROL + EVERGREEN_CRTC3_REGISTER_OFFSET, 0);
-	}
-	if (rdev->num_crtc >= 6) {
-		WREG32(EVERGREEN_CRTC_CONTROL + EVERGREEN_CRTC4_REGISTER_OFFSET, 0);
-		WREG32(EVERGREEN_CRTC_CONTROL + EVERGREEN_CRTC5_REGISTER_OFFSET, 0);
-	}
-	WREG32(EVERGREEN_CRTC_UPDATE_LOCK + EVERGREEN_CRTC0_REGISTER_OFFSET, 0);
-	WREG32(EVERGREEN_CRTC_UPDATE_LOCK + EVERGREEN_CRTC1_REGISTER_OFFSET, 0);
-	if (rdev->num_crtc >= 4) {
-		WREG32(EVERGREEN_CRTC_UPDATE_LOCK + EVERGREEN_CRTC2_REGISTER_OFFSET, 0);
-		WREG32(EVERGREEN_CRTC_UPDATE_LOCK + EVERGREEN_CRTC3_REGISTER_OFFSET, 0);
-	}
-	if (rdev->num_crtc >= 6) {
-		WREG32(EVERGREEN_CRTC_UPDATE_LOCK + EVERGREEN_CRTC4_REGISTER_OFFSET, 0);
-		WREG32(EVERGREEN_CRTC_UPDATE_LOCK + EVERGREEN_CRTC5_REGISTER_OFFSET, 0);
+	/* blank the display controllers */
+	for (i = 0; i < rdev->num_crtc; i++) {
+		crtc_enabled = RREG32(EVERGREEN_CRTC_CONTROL + crtc_offsets[i]) & EVERGREEN_CRTC_MASTER_EN;
+		if (crtc_enabled) {
+			save->crtc_enabled[i] = true;
+			tmp = RREG32(EVERGREEN_CRTC_CONTROL + crtc_offsets[i]);
+			if (!(tmp & EVERGREEN_CRTC_DISP_READ_REQUEST_DISABLE)) {
+				dce4_wait_for_vblank(rdev, i);
+				tmp |= EVERGREEN_CRTC_DISP_READ_REQUEST_DISABLE;
+				WREG32(EVERGREEN_CRTC_CONTROL + crtc_offsets[i], tmp);
+			}
+			/* wait for the next frame */
+			frame_count = radeon_get_vblank_counter(rdev, i);
+			for (j = 0; j < rdev->usec_timeout; j++) {
+				if (radeon_get_vblank_counter(rdev, i) != frame_count)
+					break;
+				udelay(1);
+			}
+		}
 	}
 
-	WREG32(D1VGA_CONTROL, 0);
-	WREG32(D2VGA_CONTROL, 0);
-	if (rdev->num_crtc >= 4) {
-		WREG32(EVERGREEN_D3VGA_CONTROL, 0);
-		WREG32(EVERGREEN_D4VGA_CONTROL, 0);
-	}
-	if (rdev->num_crtc >= 6) {
-		WREG32(EVERGREEN_D5VGA_CONTROL, 0);
-		WREG32(EVERGREEN_D6VGA_CONTROL, 0);
+	evergreen_mc_wait_for_idle(rdev);
+
+	blackout = RREG32(MC_SHARED_BLACKOUT_CNTL);
+	if ((blackout & BLACKOUT_MODE_MASK) != 1) {
+		/* Block CPU access */
+		WREG32(BIF_FB_EN, 0);
+		/* blackout the MC */
+		blackout &= ~BLACKOUT_MODE_MASK;
+		WREG32(MC_SHARED_BLACKOUT_CNTL, blackout | 1);
 	}
 }
 
 void evergreen_mc_resume(struct radeon_device *rdev, struct evergreen_mc_save *save)
 {
-	WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS_HIGH + EVERGREEN_CRTC0_REGISTER_OFFSET,
-	       upper_32_bits(rdev->mc.vram_start));
-	WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS_HIGH + EVERGREEN_CRTC0_REGISTER_OFFSET,
-	       upper_32_bits(rdev->mc.vram_start));
-	WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS + EVERGREEN_CRTC0_REGISTER_OFFSET,
-	       (u32)rdev->mc.vram_start);
-	WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS + EVERGREEN_CRTC0_REGISTER_OFFSET,
-	       (u32)rdev->mc.vram_start);
-
-	WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS_HIGH + EVERGREEN_CRTC1_REGISTER_OFFSET,
-	       upper_32_bits(rdev->mc.vram_start));
-	WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS_HIGH + EVERGREEN_CRTC1_REGISTER_OFFSET,
-	       upper_32_bits(rdev->mc.vram_start));
-	WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS + EVERGREEN_CRTC1_REGISTER_OFFSET,
-	       (u32)rdev->mc.vram_start);
-	WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS + EVERGREEN_CRTC1_REGISTER_OFFSET,
-	       (u32)rdev->mc.vram_start);
-
-	if (rdev->num_crtc >= 4) {
-		WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS_HIGH + EVERGREEN_CRTC2_REGISTER_OFFSET,
-		       upper_32_bits(rdev->mc.vram_start));
-		WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS_HIGH + EVERGREEN_CRTC2_REGISTER_OFFSET,
-		       upper_32_bits(rdev->mc.vram_start));
-		WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS + EVERGREEN_CRTC2_REGISTER_OFFSET,
-		       (u32)rdev->mc.vram_start);
-		WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS + EVERGREEN_CRTC2_REGISTER_OFFSET,
-		       (u32)rdev->mc.vram_start);
-
-		WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS_HIGH + EVERGREEN_CRTC3_REGISTER_OFFSET,
-		       upper_32_bits(rdev->mc.vram_start));
-		WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS_HIGH + EVERGREEN_CRTC3_REGISTER_OFFSET,
-		       upper_32_bits(rdev->mc.vram_start));
-		WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS + EVERGREEN_CRTC3_REGISTER_OFFSET,
-		       (u32)rdev->mc.vram_start);
-		WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS + EVERGREEN_CRTC3_REGISTER_OFFSET,
-		       (u32)rdev->mc.vram_start);
-	}
-	if (rdev->num_crtc >= 6) {
-		WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS_HIGH + EVERGREEN_CRTC4_REGISTER_OFFSET,
-		       upper_32_bits(rdev->mc.vram_start));
-		WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS_HIGH + EVERGREEN_CRTC4_REGISTER_OFFSET,
-		       upper_32_bits(rdev->mc.vram_start));
-		WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS + EVERGREEN_CRTC4_REGISTER_OFFSET,
-		       (u32)rdev->mc.vram_start);
-		WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS + EVERGREEN_CRTC4_REGISTER_OFFSET,
-		       (u32)rdev->mc.vram_start);
+	u32 tmp, frame_count;
+	int i, j;
 
-		WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS_HIGH + EVERGREEN_CRTC5_REGISTER_OFFSET,
+	/* update crtc base addresses */
+	for (i = 0; i < rdev->num_crtc; i++) {
+		WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS_HIGH + crtc_offsets[i],
 		       upper_32_bits(rdev->mc.vram_start));
-		WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS_HIGH + EVERGREEN_CRTC5_REGISTER_OFFSET,
+		WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS_HIGH + crtc_offsets[i],
 		       upper_32_bits(rdev->mc.vram_start));
-		WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS + EVERGREEN_CRTC5_REGISTER_OFFSET,
+		WREG32(EVERGREEN_GRPH_PRIMARY_SURFACE_ADDRESS + crtc_offsets[i],
 		       (u32)rdev->mc.vram_start);
-		WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS + EVERGREEN_CRTC5_REGISTER_OFFSET,
+		WREG32(EVERGREEN_GRPH_SECONDARY_SURFACE_ADDRESS + crtc_offsets[i],
 		       (u32)rdev->mc.vram_start);
 	}
-
 	WREG32(EVERGREEN_VGA_MEMORY_BASE_ADDRESS_HIGH, upper_32_bits(rdev->mc.vram_start));
 	WREG32(EVERGREEN_VGA_MEMORY_BASE_ADDRESS, (u32)rdev->mc.vram_start);
-	/* Unlock host access */
+
+	/* unblackout the MC */
+	tmp = RREG32(MC_SHARED_BLACKOUT_CNTL);
+	tmp &= ~BLACKOUT_MODE_MASK;
+	WREG32(MC_SHARED_BLACKOUT_CNTL, tmp);
+	/* allow CPU access */
+	WREG32(BIF_FB_EN, FB_READ_EN | FB_WRITE_EN);
+
+	for (i = 0; i < rdev->num_crtc; i++) {
+		if (save->crtc_enabled) {
+			tmp = RREG32(EVERGREEN_CRTC_CONTROL + crtc_offsets[i]);
+			tmp &= ~EVERGREEN_CRTC_DISP_READ_REQUEST_DISABLE;
+			WREG32(EVERGREEN_CRTC_CONTROL + crtc_offsets[i], tmp);
+			/* wait for the next frame */
+			frame_count = radeon_get_vblank_counter(rdev, i);
+			for (j = 0; j < rdev->usec_timeout; j++) {
+				if (radeon_get_vblank_counter(rdev, i) != frame_count)
+					break;
+				udelay(1);
+			}
+		}
+	}
+	/* Unlock vga access */
 	WREG32(VGA_HDP_CONTROL, save->vga_hdp_control);
 	mdelay(1);
 	WREG32(VGA_RENDER_CONTROL, save->vga_render_control);

drivers/gpu/drm/radeon/evergreen_reg.h

@@ -210,7 +210,10 @@
 #define EVERGREEN_CRTC_CONTROL                          0x6e70
 #       define EVERGREEN_CRTC_MASTER_EN                 (1 << 0)
 #       define EVERGREEN_CRTC_DISP_READ_REQUEST_DISABLE (1 << 24)
+#define EVERGREEN_CRTC_BLANK_CONTROL                    0x6e74
+#       define EVERGREEN_CRTC_BLANK_DATA_EN             (1 << 8)
 #define EVERGREEN_CRTC_STATUS                           0x6e8c
+#       define EVERGREEN_CRTC_V_BLANK                   (1 << 0)
 #define EVERGREEN_CRTC_STATUS_POSITION                  0x6e90
 #define EVERGREEN_MASTER_UPDATE_MODE                    0x6ef8
 #define EVERGREEN_CRTC_UPDATE_LOCK                      0x6ed4

drivers/gpu/drm/radeon/evergreend.h

@@ -77,6 +77,10 @@
 
 #define	CONFIG_MEMSIZE					0x5428
 
+#define	BIF_FB_EN						0x5490
+#define		FB_READ_EN					(1 << 0)
+#define		FB_WRITE_EN					(1 << 1)
+
 #define CP_ME_CNTL					0x86D8
 #define		CP_ME_HALT					(1 << 28)
 #define		CP_PFP_HALT					(1 << 26)
@@ -194,6 +198,9 @@
 #define		NOOFCHAN_MASK					0x00003000
 #define MC_SHARED_CHREMAP					0x2008
 
+#define MC_SHARED_BLACKOUT_CNTL           		0x20ac
+#define		BLACKOUT_MODE_MASK			0x00000007
+
 #define	MC_ARB_RAMCFG					0x2760
 #define		NOOFBANK_SHIFT					0
 #define		NOOFBANK_MASK					0x00000003

drivers/gpu/drm/radeon/radeon_asic.h

@@ -386,6 +386,7 @@ void r700_cp_fini(struct radeon_device *rdev);
 struct evergreen_mc_save {
 	u32 vga_render_control;
 	u32 vga_hdp_control;
+	bool crtc_enabled[RADEON_MAX_CRTCS];
 };
 
 void evergreen_pcie_gart_tlb_flush(struct radeon_device *rdev);