drm/radeon: default to 1024M gart size on rv770+

Newer asics have a lot of vram so it's less of an
issue to waste a little more space for the gart
page table.  This gives us some additional gart space
before having to migrate to non-gart system ram
for games, etc. where we use up most of vram.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/radeon_device.c

@@ -1003,16 +1003,28 @@ static void radeon_check_arguments(struct radeon_device *rdev)
 		radeon_vram_limit = 0;
 	}
 
+	if (radeon_gart_size == -1) {
+		/* default to a larger gart size on newer asics */
+		if (rdev->family >= CHIP_RV770)
+			radeon_gart_size = 1024;
+		else
+			radeon_gart_size = 512;
+	}
 	/* gtt size must be power of two and greater or equal to 32M */
 	if (radeon_gart_size < 32) {
-		dev_warn(rdev->dev, "gart size (%d) too small forcing to 512M\n",
+		dev_warn(rdev->dev, "gart size (%d) too small\n",
 				radeon_gart_size);
-		radeon_gart_size = 512;
-
+		if (rdev->family >= CHIP_RV770)
+			radeon_gart_size = 1024;
+		else
+			radeon_gart_size = 512;
 	} else if (!radeon_check_pot_argument(radeon_gart_size)) {
 		dev_warn(rdev->dev, "gart size (%d) must be a power of 2\n",
 				radeon_gart_size);
-		radeon_gart_size = 512;
+		if (rdev->family >= CHIP_RV770)
+			radeon_gart_size = 1024;
+		else
+			radeon_gart_size = 512;
 	}
 	rdev->mc.gtt_size = (uint64_t)radeon_gart_size << 20;
 
@@ -1144,7 +1156,7 @@ int radeon_device_init(struct radeon_device *rdev,
 	rdev->family = flags & RADEON_FAMILY_MASK;
 	rdev->is_atom_bios = false;
 	rdev->usec_timeout = RADEON_MAX_USEC_TIMEOUT;
-	rdev->mc.gtt_size = radeon_gart_size * 1024 * 1024;
+	rdev->mc.gtt_size = 512 * 1024 * 1024;
 	rdev->accel_working = false;
 	/* set up ring ids */
 	for (i = 0; i < RADEON_NUM_RINGS; i++) {

drivers/gpu/drm/radeon/radeon_drv.c

@@ -154,7 +154,7 @@ int radeon_dynclks = -1;
 int radeon_r4xx_atom = 0;
 int radeon_agpmode = 0;
 int radeon_vram_limit = 0;
-int radeon_gart_size = 512; /* default gart size */
+int radeon_gart_size = -1; /* auto */
 int radeon_benchmarking = 0;
 int radeon_testing = 0;
 int radeon_connector_table = 0;
@@ -187,7 +187,7 @@ module_param_named(vramlimit, radeon_vram_limit, int, 0600);
 MODULE_PARM_DESC(agpmode, "AGP Mode (-1 == PCI)");
 module_param_named(agpmode, radeon_agpmode, int, 0444);
 
-MODULE_PARM_DESC(gartsize, "Size of PCIE/IGP gart to setup in megabytes (32, 64, etc)");
+MODULE_PARM_DESC(gartsize, "Size of PCIE/IGP gart to setup in megabytes (32, 64, etc., -1 = auto)");
 module_param_named(gartsize, radeon_gart_size, int, 0600);
 
 MODULE_PARM_DESC(benchmark, "Run benchmark");