drm/radeon/kms/atom: make sure tables are valid (v2)

Check that atom cmd and data tables are valid
before using them.

(v2)
- fix some whitespace errors noticed by Rafał Miłecki
- check a few more cases

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

1 files changed, 44 insertions, 30 deletions

diff --git a/drivers/gpu/drm/radeon/rs690.c b/drivers/gpu/drm/radeon/rs690.c
index e356935b0283..f758d5cc1160 100644
--- a/drivers/gpu/drm/radeon/rs690.c
+++ b/drivers/gpu/drm/radeon/rs690.c
@@ -58,42 +58,57 @@ static void rs690_gpu_init(struct radeon_device *rdev)
 	}
 }
 
+union igp_info {
+	struct _ATOM_INTEGRATED_SYSTEM_INFO info;
+	struct _ATOM_INTEGRATED_SYSTEM_INFO_V2 info_v2;
+};
+
 void rs690_pm_info(struct radeon_device *rdev)
 {
 	int index = GetIndexIntoMasterTable(DATA, IntegratedSystemInfo);
-	struct _ATOM_INTEGRATED_SYSTEM_INFO *info;
-	struct _ATOM_INTEGRATED_SYSTEM_INFO_V2 *info_v2;
-	void *ptr;
+	union igp_info *info;
 	uint16_t data_offset;
 	uint8_t frev, crev;
 	fixed20_12 tmp;
 
-	atom_parse_data_header(rdev->mode_info.atom_context, index, NULL,
-			       &frev, &crev, &data_offset);
-	ptr = rdev->mode_info.atom_context->bios + data_offset;
-	info = (struct _ATOM_INTEGRATED_SYSTEM_INFO *)ptr;
-	info_v2 = (struct _ATOM_INTEGRATED_SYSTEM_INFO_V2 *)ptr;
-	/* Get various system informations from bios */
-	switch (crev) {
-	case 1:
-		tmp.full = rfixed_const(100);
-		rdev->pm.igp_sideport_mclk.full = rfixed_const(info->ulBootUpMemoryClock);
-		rdev->pm.igp_sideport_mclk.full = rfixed_div(rdev->pm.igp_sideport_mclk, tmp);
-		rdev->pm.igp_system_mclk.full = rfixed_const(le16_to_cpu(info->usK8MemoryClock));
-		rdev->pm.igp_ht_link_clk.full = rfixed_const(le16_to_cpu(info->usFSBClock));
-		rdev->pm.igp_ht_link_width.full = rfixed_const(info->ucHTLinkWidth);
-		break;
-	case 2:
-		tmp.full = rfixed_const(100);
-		rdev->pm.igp_sideport_mclk.full = rfixed_const(info_v2->ulBootUpSidePortClock);
-		rdev->pm.igp_sideport_mclk.full = rfixed_div(rdev->pm.igp_sideport_mclk, tmp);
-		rdev->pm.igp_system_mclk.full = rfixed_const(info_v2->ulBootUpUMAClock);
-		rdev->pm.igp_system_mclk.full = rfixed_div(rdev->pm.igp_system_mclk, tmp);
-		rdev->pm.igp_ht_link_clk.full = rfixed_const(info_v2->ulHTLinkFreq);
-		rdev->pm.igp_ht_link_clk.full = rfixed_div(rdev->pm.igp_ht_link_clk, tmp);
-		rdev->pm.igp_ht_link_width.full = rfixed_const(le16_to_cpu(info_v2->usMinHTLinkWidth));
-		break;
-	default:
+	if (atom_parse_data_header(rdev->mode_info.atom_context, index, NULL,
+				   &frev, &crev, &data_offset)) {
+		info = (union igp_info *)(rdev->mode_info.atom_context->bios + data_offset);
+
+		/* Get various system informations from bios */
+		switch (crev) {
+		case 1:
+			tmp.full = rfixed_const(100);
+			rdev->pm.igp_sideport_mclk.full = rfixed_const(info->info.ulBootUpMemoryClock);
+			rdev->pm.igp_sideport_mclk.full = rfixed_div(rdev->pm.igp_sideport_mclk, tmp);
+			rdev->pm.igp_system_mclk.full = rfixed_const(le16_to_cpu(info->info.usK8MemoryClock));
+			rdev->pm.igp_ht_link_clk.full = rfixed_const(le16_to_cpu(info->info.usFSBClock));
+			rdev->pm.igp_ht_link_width.full = rfixed_const(info->info.ucHTLinkWidth);
+			break;
+		case 2:
+			tmp.full = rfixed_const(100);
+			rdev->pm.igp_sideport_mclk.full = rfixed_const(info->info_v2.ulBootUpSidePortClock);
+			rdev->pm.igp_sideport_mclk.full = rfixed_div(rdev->pm.igp_sideport_mclk, tmp);
+			rdev->pm.igp_system_mclk.full = rfixed_const(info->info_v2.ulBootUpUMAClock);
+			rdev->pm.igp_system_mclk.full = rfixed_div(rdev->pm.igp_system_mclk, tmp);
+			rdev->pm.igp_ht_link_clk.full = rfixed_const(info->info_v2.ulHTLinkFreq);
+			rdev->pm.igp_ht_link_clk.full = rfixed_div(rdev->pm.igp_ht_link_clk, tmp);
+			rdev->pm.igp_ht_link_width.full = rfixed_const(le16_to_cpu(info->info_v2.usMinHTLinkWidth));
+			break;
+		default:
+			tmp.full = rfixed_const(100);
+			/* We assume the slower possible clock ie worst case */
+			/* DDR 333Mhz */
+			rdev->pm.igp_sideport_mclk.full = rfixed_const(333);
+			/* FIXME: system clock ? */
+			rdev->pm.igp_system_mclk.full = rfixed_const(100);
+			rdev->pm.igp_system_mclk.full = rfixed_div(rdev->pm.igp_system_mclk, tmp);
+			rdev->pm.igp_ht_link_clk.full = rfixed_const(200);
+			rdev->pm.igp_ht_link_width.full = rfixed_const(8);
+			DRM_ERROR("No integrated system info for your GPU, using safe default\n");
+			break;
+		}
+	} else {
 		tmp.full = rfixed_const(100);
 		/* We assume the slower possible clock ie worst case */
 		/* DDR 333Mhz */
@@ -104,7 +119,6 @@ void rs690_pm_info(struct radeon_device *rdev)
 		rdev->pm.igp_ht_link_clk.full = rfixed_const(200);
 		rdev->pm.igp_ht_link_width.full = rfixed_const(8);
 		DRM_ERROR("No integrated system info for your GPU, using safe default\n");
-		break;
 	}
 	/* Compute various bandwidth */
 	/* k8_bandwidth = (memory_clk / 2) * 2 * 8 * 0.5 = memory_clk * 4  */