drm/radeon: add a module parameter to control deep color support

Some monitors seem to have problems with deep color enabled, even
though they claim to support it.  I'm not sure if the monitor
need a quirk or if the driver is doing something the monitor doesn't
like.  At this point lets just disable deep color by default like
we did for hdmi audio and work through the bugs so we can eventually
enable it by default.

bug:
https://bugs.freedesktop.org/show_bug.cgi?id=80531

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index 4b0bbf88d5c0f19b3d2cda822e2634c51d1268fa..a2e1ed8d4ed434e262f8cb68c74e4f46bf30bb16 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -102,6 +102,7 @@ extern int radeon_runtime_pm;
 extern int radeon_hard_reset;
 extern int radeon_vm_size;
 extern int radeon_vm_block_size;
+extern int radeon_deep_color;
 
 /*
  * Copy from radeon_drv.h so we don't have to include both and have conflicting

diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c
index 1b9177ed181fa2827bbbeae422bddb2cf06ad19f..44831197e82eed7e441399818408a8599e697dde 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -199,6 +199,9 @@ int radeon_get_monitor_bpc(struct drm_connector *connector)
                }
        }
 
+       if ((radeon_deep_color == 0) && (bpc > 8))
+               bpc = 8;
+
        DRM_DEBUG("%s: Display bpc=%d, returned bpc=%d\n",
                          connector->name, connector->display_info.bpc, bpc);
 

diff --git a/drivers/gpu/drm/radeon/radeon_drv.c b/drivers/gpu/drm/radeon/radeon_drv.c
index 6e301741338689abf0328ced81d1118ec5b4dbdd..cb1421369e3a2eaa111a8c6d5f3b1e248e72beec 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_drv.c
+++ b/drivers/gpu/drm/radeon/radeon_drv.c
@@ -175,6 +175,7 @@ int radeon_runtime_pm = -1;
 int radeon_hard_reset = 0;
 int radeon_vm_size = 4096;
 int radeon_vm_block_size = 9;
+int radeon_deep_color = 0;
 
 MODULE_PARM_DESC(no_wb, "Disable AGP writeback for scratch registers");
 module_param_named(no_wb, radeon_no_wb, int, 0444);
@@ -248,6 +249,9 @@ module_param_named(vm_size, radeon_vm_size, int, 0444);
 MODULE_PARM_DESC(vm_block_size, "VM page table size in bits (default 9)");
 module_param_named(vm_block_size, radeon_vm_block_size, int, 0444);
 
+MODULE_PARM_DESC(deep_color, "Deep Color support (1 = enable, 0 = disable (default))");
+module_param_named(deep_color, radeon_deep_color, int, 0444);
+
 static struct pci_device_id pciidlist[] = {
        radeon_PCI_IDS
 };