| Message ID | 20201101100657.12087-6-ankit.k.nautiyal@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add support for DP-HDMI2.1 PCON | expand |
> -----Original Message----- > From: Nautiyal, Ankit K <ankit.k.nautiyal@intel.com> > Sent: Sunday, November 1, 2020 3:37 PM > To: intel-gfx@lists.freedesktop.org > Cc: dri-devel@lists.freedesktop.org; Shankar, Uma <uma.shankar@intel.com>; > Kulkarni, Vandita <vandita.kulkarni@intel.com>; ville.syrjala@linux.intel.com; > Sharma, Swati2 <swati2.sharma@intel.com> > Subject: [PATCH v2 05/13] drm/dp_helper: Add support for link failure detection > > From: Swati Sharma <swati2.sharma@intel.com> > > There are specific DPCDs defined for detecting link failures between the PCON > and HDMI sink and check the link status. In case of link failure, PCON will > communicate the same using an IRQ_HPD to source. > HDMI sink would have indicated the same to PCON using SCDC interrupt > mechanism. While source can always read final HDMI sink's status using I2C over > AUX, it is easier and faster to read the PCONs already read HDMI sink status > registers. > > This patch adds the DPCDs required for link failure detection and provide a > helper function for printing error count/lane which might help in debugging the > link failure issues. > > v2: Addressed comments from Uma Shankar: > -rephrased the commit message, as per the code. > -fixed styling issues > -added documentation for the helper function. Reviewed-by: Uma Shankar <uma.shankar@intel.com> > Signed-off-by: Swati Sharma <swati2.sharma@intel.com> > Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com> > --- > drivers/gpu/drm/drm_dp_helper.c | 39 +++++++++++++++++++++++++++++++++ > include/drm/drm_dp_helper.h | 17 ++++++++++++++ > 2 files changed, 56 insertions(+) > > diff --git a/drivers/gpu/drm/drm_dp_helper.c > b/drivers/gpu/drm/drm_dp_helper.c index b67580294c4e..05782091e7e1 100644 > --- a/drivers/gpu/drm/drm_dp_helper.c > +++ b/drivers/gpu/drm/drm_dp_helper.c > @@ -2893,3 +2893,42 @@ int drm_dp_pcon_hdmi_link_mode(struct > drm_dp_aux *aux, u8 *frl_trained_mask) > return mode; > } > EXPORT_SYMBOL(drm_dp_pcon_hdmi_link_mode); > + > +/** > + * drm_dp_pcon_hdmi_frl_link_error_count() - print the error count per > +lane > + * during link failure between PCON and HDMI sink > + * @aux: DisplayPort AUX channel > + * @connector: DRM connector > + * code. > + **/ > + > +void drm_dp_pcon_hdmi_frl_link_error_count(struct drm_dp_aux *aux, > + struct drm_connector *connector) { > + u8 buf, error_count; > + int i, num_error; > + struct drm_hdmi_info *hdmi = &connector->display_info.hdmi; > + > + for (i = 0; i < hdmi->max_lanes; i++) { > + if (drm_dp_dpcd_readb(aux, > DP_PCON_HDMI_ERROR_STATUS_LN0 + i, &buf) < 0) > + return; > + > + error_count = buf & DP_PCON_HDMI_ERROR_COUNT_MASK; > + switch (error_count) { > + case DP_PCON_HDMI_ERROR_COUNT_HUNDRED_PLUS: > + num_error = 100; > + break; > + case DP_PCON_HDMI_ERROR_COUNT_TEN_PLUS: > + num_error = 10; > + break; > + case DP_PCON_HDMI_ERROR_COUNT_THREE_PLUS: > + num_error = 3; > + break; > + default: > + num_error = 0; > + } > + > + DRM_ERROR("More than %d errors since the last read for lane > %d", num_error, i); > + } > +} > +EXPORT_SYMBOL(drm_dp_pcon_hdmi_frl_link_error_count); > diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index > e2ed6bfaae89..bdbe9bbdb244 100644 > --- a/include/drm/drm_dp_helper.h > +++ b/include/drm/drm_dp_helper.h > @@ -946,6 +946,11 @@ struct drm_device; > # define DP_CEC_IRQ (1 << 2) > > #define DP_LINK_SERVICE_IRQ_VECTOR_ESI0 0x2005 /* 1.2 */ > +# define RX_CAP_CHANGED (1 << 0) > +# define LINK_STATUS_CHANGED (1 << 1) > +# define STREAM_STATUS_CHANGED (1 << 2) > +# define HDMI_LINK_STATUS_CHANGED (1 << 3) > +# define CONNECTED_OFF_ENTRY_REQUESTED (1 << 4) > > #define DP_PSR_ERROR_STATUS 0x2006 /* XXX 1.2? */ > # define DP_PSR_LINK_CRC_ERROR (1 << 0) > @@ -1130,6 +1135,16 @@ struct drm_device; > #define DP_PROTOCOL_CONVERTER_CONTROL_2 0x3052 /* DP 1.3 > */ > # define DP_CONVERSION_TO_YCBCR422_ENABLE (1 << 0) /* DP 1.3 */ > > +/* PCON Downstream HDMI ERROR Status per Lane */ > +#define DP_PCON_HDMI_ERROR_STATUS_LN0 0x3037 > +#define DP_PCON_HDMI_ERROR_STATUS_LN1 0x3038 > +#define DP_PCON_HDMI_ERROR_STATUS_LN2 0x3039 > +#define DP_PCON_HDMI_ERROR_STATUS_LN3 0x303A > +# define DP_PCON_HDMI_ERROR_COUNT_MASK (0x7 << 0) > +# define DP_PCON_HDMI_ERROR_COUNT_THREE_PLUS (1 << 0) > +# define DP_PCON_HDMI_ERROR_COUNT_TEN_PLUS (1 << 1) > +# define DP_PCON_HDMI_ERROR_COUNT_HUNDRED_PLUS (1 << 2) > + > /* HDCP 1.3 and HDCP 2.2 */ > #define DP_AUX_HDCP_BKSV 0x68000 > #define DP_AUX_HDCP_RI_PRIME 0x68005 > @@ -2047,5 +2062,7 @@ int drm_dp_pcon_frl_enable(struct drm_dp_aux *aux); > > bool drm_dp_pcon_hdmi_link_active(struct drm_dp_aux *aux); int > drm_dp_pcon_hdmi_link_mode(struct drm_dp_aux *aux, u8 *frl_trained_mask); > +void drm_dp_pcon_hdmi_frl_link_error_count(struct drm_dp_aux *aux, > + struct drm_connector *connector); > > #endif /* _DRM_DP_HELPER_H_ */ > -- > 2.17.1
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index b67580294c4e..05782091e7e1 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -2893,3 +2893,42 @@ int drm_dp_pcon_hdmi_link_mode(struct drm_dp_aux *aux, u8 *frl_trained_mask) return mode; } EXPORT_SYMBOL(drm_dp_pcon_hdmi_link_mode); + +/** + * drm_dp_pcon_hdmi_frl_link_error_count() - print the error count per lane + * during link failure between PCON and HDMI sink + * @aux: DisplayPort AUX channel + * @connector: DRM connector + * code. + **/ + +void drm_dp_pcon_hdmi_frl_link_error_count(struct drm_dp_aux *aux, + struct drm_connector *connector) +{ + u8 buf, error_count; + int i, num_error; + struct drm_hdmi_info *hdmi = &connector->display_info.hdmi; + + for (i = 0; i < hdmi->max_lanes; i++) { + if (drm_dp_dpcd_readb(aux, DP_PCON_HDMI_ERROR_STATUS_LN0 + i, &buf) < 0) + return; + + error_count = buf & DP_PCON_HDMI_ERROR_COUNT_MASK; + switch (error_count) { + case DP_PCON_HDMI_ERROR_COUNT_HUNDRED_PLUS: + num_error = 100; + break; + case DP_PCON_HDMI_ERROR_COUNT_TEN_PLUS: + num_error = 10; + break; + case DP_PCON_HDMI_ERROR_COUNT_THREE_PLUS: + num_error = 3; + break; + default: + num_error = 0; + } + + DRM_ERROR("More than %d errors since the last read for lane %d", num_error, i); + } +} +EXPORT_SYMBOL(drm_dp_pcon_hdmi_frl_link_error_count); diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index e2ed6bfaae89..bdbe9bbdb244 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -946,6 +946,11 @@ struct drm_device; # define DP_CEC_IRQ (1 << 2) #define DP_LINK_SERVICE_IRQ_VECTOR_ESI0 0x2005 /* 1.2 */ +# define RX_CAP_CHANGED (1 << 0) +# define LINK_STATUS_CHANGED (1 << 1) +# define STREAM_STATUS_CHANGED (1 << 2) +# define HDMI_LINK_STATUS_CHANGED (1 << 3) +# define CONNECTED_OFF_ENTRY_REQUESTED (1 << 4) #define DP_PSR_ERROR_STATUS 0x2006 /* XXX 1.2? */ # define DP_PSR_LINK_CRC_ERROR (1 << 0) @@ -1130,6 +1135,16 @@ struct drm_device; #define DP_PROTOCOL_CONVERTER_CONTROL_2 0x3052 /* DP 1.3 */ # define DP_CONVERSION_TO_YCBCR422_ENABLE (1 << 0) /* DP 1.3 */ +/* PCON Downstream HDMI ERROR Status per Lane */ +#define DP_PCON_HDMI_ERROR_STATUS_LN0 0x3037 +#define DP_PCON_HDMI_ERROR_STATUS_LN1 0x3038 +#define DP_PCON_HDMI_ERROR_STATUS_LN2 0x3039 +#define DP_PCON_HDMI_ERROR_STATUS_LN3 0x303A +# define DP_PCON_HDMI_ERROR_COUNT_MASK (0x7 << 0) +# define DP_PCON_HDMI_ERROR_COUNT_THREE_PLUS (1 << 0) +# define DP_PCON_HDMI_ERROR_COUNT_TEN_PLUS (1 << 1) +# define DP_PCON_HDMI_ERROR_COUNT_HUNDRED_PLUS (1 << 2) + /* HDCP 1.3 and HDCP 2.2 */ #define DP_AUX_HDCP_BKSV 0x68000 #define DP_AUX_HDCP_RI_PRIME 0x68005 @@ -2047,5 +2062,7 @@ int drm_dp_pcon_frl_enable(struct drm_dp_aux *aux); bool drm_dp_pcon_hdmi_link_active(struct drm_dp_aux *aux); int drm_dp_pcon_hdmi_link_mode(struct drm_dp_aux *aux, u8 *frl_trained_mask); +void drm_dp_pcon_hdmi_frl_link_error_count(struct drm_dp_aux *aux, + struct drm_connector *connector); #endif /* _DRM_DP_HELPER_H_ */