[Nouveau] [PATCH 2/2] connector: allow 225/297MHz pixel clocks for HDMI on Fermi/Kepler

[Ilia Mirkin]

Some Fermi's apparently alow allow 297MHz clocks, so create a parameter
which allows end-users to set it themselves until we have a reliable way
to determine the board's maximum pixel clocks.

Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
---
 drm/nouveau/nouveau_connector.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drm/nouveau/nouveau_connector.c b/drm/nouveau/nouveau_connector.c
index 4c8f6ef..f5806eb 100644
--- a/drm/nouveau/nouveau_connector.c
+++ b/drm/nouveau/nouveau_connector.c
@@ -56,6 +56,10 @@ MODULE_PARM_DESC(duallink, "Allow dual-link TMDS (default: enabled)");
 int nouveau_duallink = 1;
 module_param_named(duallink, nouveau_duallink, int, 0400);
 
+MODULE_PARM_DESC(hdmimhz, "Force a maximum HDMI pixel clock (in MHz)");
+int nouveau_hdmimhz = 0;
+module_param_named(hdmimhz, nouveau_hdmimhz, int, 0400);
+
 struct nouveau_encoder *
 find_encoder(struct drm_connector *connector, int type)
 {
@@ -815,6 +819,17 @@ get_tmds_link_bandwidth(struct drm_connector *connector)
 	struct nouveau_drm *drm = nouveau_drm(connector->dev);
 	struct dcb_output *dcb = nv_connector->detected_encoder->dcb;
 
+	if (drm_detect_hdmi_monitor(nv_connector->edid)) {
+		if (nouveau_hdmimhz > 0)
+			return nouveau_hdmimhz * 1000;
+		/* Note: these limits are conservative, some Fermi's
+		 * can do 297 MHz. Unclear how this can be determined.
+		 */
+		if (drm->device.info.family >= NV_DEVICE_INFO_V0_KEPLER)
+			return 297000;
+		if (drm->device.info.family >= NV_DEVICE_INFO_V0_FERMI)
+			return 225000;
+	}
 	if (dcb->location != DCB_LOC_ON_CHIP ||
 	    drm->device.info.chipset >= 0x46)
 		return 165000;
-- 
2.4.10