drm/radeon/kms: fix vram_width calculation on r6xx/r7xx

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/r600.c

@@ -339,11 +339,10 @@ int r600_mc_init(struct radeon_device *rdev)
 {
 	fixed20_12 a;
 	u32 tmp;
-	int chansize;
+	int chansize, numchan;
 	int r;
 
 	/* Get VRAM informations */
-	rdev->mc.vram_width = 128;
 	rdev->mc.vram_is_ddr = true;
 	tmp = RREG32(RAMCFG);
 	if (tmp & CHANSIZE_OVERRIDE) {
@@ -353,17 +352,23 @@ int r600_mc_init(struct radeon_device *rdev)
 	} else {
 		chansize = 32;
 	}
-	if (rdev->family == CHIP_R600) {
-		rdev->mc.vram_width = 8 * chansize;
-	} else if (rdev->family == CHIP_RV670) {
-		rdev->mc.vram_width = 4 * chansize;
-	} else if ((rdev->family == CHIP_RV610) ||
-			(rdev->family == CHIP_RV620)) {
-		rdev->mc.vram_width = chansize;
-	} else if ((rdev->family == CHIP_RV630) ||
-			(rdev->family == CHIP_RV635)) {
-		rdev->mc.vram_width = 2 * chansize;
+	tmp = RREG32(CHMAP);
+	switch ((tmp & NOOFCHAN_MASK) >> NOOFCHAN_SHIFT) {
+	case 0:
+	default:
+		numchan = 1;
+		break;
+	case 1:
+		numchan = 2;
+		break;
+	case 2:
+		numchan = 4;
+		break;
+	case 3:
+		numchan = 8;
+		break;
 	}
+	rdev->mc.vram_width = numchan * chansize;
 	/* Could aper size report 0 ? */
 	rdev->mc.aper_base = drm_get_resource_start(rdev->ddev, 0);
 	rdev->mc.aper_size = drm_get_resource_len(rdev->ddev, 0);

drivers/gpu/drm/radeon/r600d.h

@@ -270,6 +270,10 @@
 #define	PCIE_PORT_INDEX					0x0038
 #define	PCIE_PORT_DATA					0x003C
 
+#define CHMAP						0x2004
+#define		NOOFCHAN_SHIFT					12
+#define		NOOFCHAN_MASK					0x00003000
+
 #define RAMCFG						0x2408
 #define		NOOFBANK_SHIFT					0
 #define		NOOFBANK_MASK					0x00000001

drivers/gpu/drm/radeon/rv770.c

@@ -774,14 +774,36 @@ int rv770_mc_init(struct radeon_device *rdev)
 {
 	fixed20_12 a;
 	u32 tmp;
+	int chansize, numchan;
 	int r;
 
 	/* Get VRAM informations */
-	/* FIXME: Don't know how to determine vram width, need to check
-	 * vram_width usage
-	 */
-	rdev->mc.vram_width = 128;
 	rdev->mc.vram_is_ddr = true;
+	tmp = RREG32(MC_ARB_RAMCFG);
+	if (tmp & CHANSIZE_OVERRIDE) {
+		chansize = 16;
+	} else if (tmp & CHANSIZE_MASK) {
+		chansize = 64;
+	} else {
+		chansize = 32;
+	}
+	tmp = RREG32(MC_SHARED_CHMAP);
+	switch ((tmp & NOOFCHAN_MASK) >> NOOFCHAN_SHIFT) {
+	case 0:
+	default:
+		numchan = 1;
+		break;
+	case 1:
+		numchan = 2;
+		break;
+	case 2:
+		numchan = 4;
+		break;
+	case 3:
+		numchan = 8;
+		break;
+	}
+	rdev->mc.vram_width = numchan * chansize;
 	/* Could aper size report 0 ? */
 	rdev->mc.aper_base = drm_get_resource_start(rdev->ddev, 0);
 	rdev->mc.aper_size = drm_get_resource_len(rdev->ddev, 0);

drivers/gpu/drm/radeon/rv770d.h

@@ -129,6 +129,10 @@
 #define HDP_REG_COHERENCY_FLUSH_CNTL			0x54A0
 #define	HDP_TILING_CONFIG				0x2F3C
 
+#define MC_SHARED_CHMAP						0x2004
+#define		NOOFCHAN_SHIFT					12
+#define		NOOFCHAN_MASK					0x00003000
+
 #define	MC_ARB_RAMCFG					0x2760
 #define		NOOFBANK_SHIFT					0
 #define		NOOFBANK_MASK					0x00000003
@@ -142,6 +146,7 @@
 #define		CHANSIZE_MASK					0x00000100
 #define		BURSTLENGTH_SHIFT				9
 #define		BURSTLENGTH_MASK				0x00000200
+#define		CHANSIZE_OVERRIDE				(1 << 11)
 #define	MC_VM_AGP_TOP					0x2028
 #define	MC_VM_AGP_BOT					0x202C
 #define	MC_VM_AGP_BASE					0x2030