[PATCH 06/18] drm/dp: Pimp drm_dp_downstream_max_bpc()
Aaron Ma
aaron.ma at canonical.com
Mon Mar 22 15:47:32 UTC 2021
From: Ville Syrjälä <ville.syrjala at linux.intel.com>
BugLink: https://bugs.launchpad.net/bugs/1920777
Deal with more cases in drm_dp_downstream_max_bpc():
- DPCD 1.0 -> assume 8bpc for non-DP
- DPCD 1.1+ DP (or DP++ with DP sink) -> allow anything
- DPCD 1.1+ TMDS -> check the caps, assume 8bpc if the value is crap
- anything else -> assume 8bpc
v2: Use Returns: for kdoc (Lyude)
Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200904115354.25336-8-ville.syrjala@linux.intel.com
Reviewed-by: Lyude Paul <lyude at redhat.com>
Acked-by: Daniel Vetter <daniel.vetter at ffwll.ch>
(backported from commit 42f2562ca1b52810415107d919535c552196384e)
Signed-off-by: Aaron Ma <aaron.ma at canonical.com>
---
drivers/gpu/drm/drm_dp_helper.c | 57 ++++++++++++-------
.../drm/i915/display/intel_display_debugfs.c | 3 +-
drivers/gpu/drm/i915/display/intel_dp.c | 2 +-
include/drm/drm_dp_helper.h | 10 +++-
4 files changed, 47 insertions(+), 25 deletions(-)
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index bf2089f83422..b5e35088b2c0 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -514,32 +514,44 @@ int drm_dp_downstream_max_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
EXPORT_SYMBOL(drm_dp_downstream_max_clock);
/**
- * drm_dp_downstream_max_bpc() - extract branch device max
+ * drm_dp_downstream_max_bpc() - extract downstream facing port max
* bits per component
* @dpcd: DisplayPort configuration data
- * @port_cap: port capabilities
+ * @port_cap: downstream facing port capabilities
+ * @edid: EDID
*
- * Returns max bpc on success or 0 if max bpc not defined
+ * Returns: Max bpc on success or 0 if max bpc not defined
*/
int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
- const u8 port_cap[4])
+ const u8 port_cap[4],
+ const struct edid *edid)
{
- int type = port_cap[0] & DP_DS_PORT_TYPE_MASK;
- bool detailed_cap_info = dpcd[DP_DOWNSTREAMPORT_PRESENT] &
- DP_DETAILED_CAP_INFO_AVAILABLE;
- int bpc;
-
- if (!detailed_cap_info)
+ if (!drm_dp_is_branch(dpcd))
return 0;
- switch (type) {
- case DP_DS_PORT_TYPE_VGA:
- case DP_DS_PORT_TYPE_DVI:
- case DP_DS_PORT_TYPE_HDMI:
+ if (dpcd[DP_DPCD_REV] < 0x11) {
+ switch (dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_TYPE_MASK) {
+ case DP_DWN_STRM_PORT_TYPE_DP:
+ return 0;
+ default:
+ return 8;
+ }
+ }
+
+ switch (port_cap[0] & DP_DS_PORT_TYPE_MASK) {
+ case DP_DS_PORT_TYPE_DP:
+ return 0;
case DP_DS_PORT_TYPE_DP_DUALMODE:
- bpc = port_cap[2] & DP_DS_MAX_BPC_MASK;
+ if (is_edid_digital_input_dp(edid))
+ return 0;
+ fallthrough;
+ case DP_DS_PORT_TYPE_HDMI:
+ case DP_DS_PORT_TYPE_DVI:
+ case DP_DS_PORT_TYPE_VGA:
+ if ((dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DETAILED_CAP_INFO_AVAILABLE) == 0)
+ return 8;
- switch (bpc) {
+ switch (port_cap[2] & DP_DS_MAX_BPC_MASK) {
case DP_DS_8BPC:
return 8;
case DP_DS_10BPC:
@@ -548,10 +560,12 @@ int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
return 12;
case DP_DS_16BPC:
return 16;
+ default:
+ return 8;
}
- /* fall through */
+ break;
default:
- return 0;
+ return 8;
}
}
EXPORT_SYMBOL(drm_dp_downstream_max_bpc);
@@ -574,12 +588,15 @@ EXPORT_SYMBOL(drm_dp_downstream_id);
* @m: pointer for debugfs file
* @dpcd: DisplayPort configuration data
* @port_cap: port capabilities
+ * @edid: EDID
* @aux: DisplayPort AUX channel
*
*/
void drm_dp_downstream_debug(struct seq_file *m,
const u8 dpcd[DP_RECEIVER_CAP_SIZE],
- const u8 port_cap[4], struct drm_dp_aux *aux)
+ const u8 port_cap[4],
+ const struct edid *edid,
+ struct drm_dp_aux *aux)
{
bool detailed_cap_info = dpcd[DP_DOWNSTREAMPORT_PRESENT] &
DP_DETAILED_CAP_INFO_AVAILABLE;
@@ -646,7 +663,7 @@ void drm_dp_downstream_debug(struct seq_file *m,
seq_printf(m, "\t\tMax TMDS clock: %d kHz\n", clk);
}
- bpc = drm_dp_downstream_max_bpc(dpcd, port_cap);
+ bpc = drm_dp_downstream_max_bpc(dpcd, port_cap, edid);
if (bpc > 0)
seq_printf(m, "\t\tMax bpc: %d\n", bpc);
diff --git a/drivers/gpu/drm/i915/display/intel_display_debugfs.c b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
index 70525623bcdf..e90e171e916a 100644
--- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
+++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
@@ -617,6 +617,7 @@ static void intel_dp_info(struct seq_file *m,
{
struct intel_encoder *intel_encoder = intel_attached_encoder(intel_connector);
struct intel_dp *intel_dp = enc_to_intel_dp(intel_encoder);
+ const struct drm_property_blob *edid = intel_connector->base.edid_blob_ptr;
seq_printf(m, "\tDPCD rev: %x\n", intel_dp->dpcd[DP_DPCD_REV]);
seq_printf(m, "\taudio support: %s\n", yesno(intel_dp->has_audio));
@@ -624,7 +625,7 @@ static void intel_dp_info(struct seq_file *m,
intel_panel_info(m, &intel_connector->panel);
drm_dp_downstream_debug(m, intel_dp->dpcd, intel_dp->downstream_ports,
- &intel_dp->aux);
+ edid ? edid->data : NULL, &intel_dp->aux);
if (intel_connector->hdcp.shim) {
seq_puts(m, "\tHDCP version: ");
intel_hdcp_info(m, intel_connector);
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index eee4bfa8f8e6..17149d5c27db 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -6138,7 +6138,7 @@ intel_dp_set_edid(struct intel_dp *intel_dp)
intel_dp->dfp.max_bpc =
drm_dp_downstream_max_bpc(intel_dp->dpcd,
- intel_dp->downstream_ports);
+ intel_dp->downstream_ports, edid);
drm_dbg_kms(&i915->drm, "[CONNECTOR:%d:%s] DFP max bpc %d\n",
connector->base.base.id, connector->base.name,
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index cba082cce9b8..18fc550fe963 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -1628,10 +1628,14 @@ bool drm_dp_downstream_is_tmds(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
int drm_dp_downstream_max_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
const u8 port_cap[4]);
int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
- const u8 port_cap[4]);
+ const u8 port_cap[4],
+ const struct edid *edid);
int drm_dp_downstream_id(struct drm_dp_aux *aux, char id[6]);
-void drm_dp_downstream_debug(struct seq_file *m, const u8 dpcd[DP_RECEIVER_CAP_SIZE],
- const u8 port_cap[4], struct drm_dp_aux *aux);
+void drm_dp_downstream_debug(struct seq_file *m,
+ const u8 dpcd[DP_RECEIVER_CAP_SIZE],
+ const u8 port_cap[4],
+ const struct edid *edid,
+ struct drm_dp_aux *aux);
void drm_dp_remote_aux_init(struct drm_dp_aux *aux);
void drm_dp_aux_init(struct drm_dp_aux *aux);
--
2.30.2
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