[PATCH 20/20] drm/i915: write AVI infoframes for LSPCON

Ville Syrjälä ville.syrjala at linux.intel.com
Thu Jul 13 12:27:32 UTC 2017


On Thu, Jul 13, 2017 at 11:11:53AM +0530, Sharma, Shashank wrote:
> Regards
> 
> Shashank
> 
> 
> On 7/12/2017 10:54 PM, Ville Syrjälä wrote:
> > On Mon, Jul 10, 2017 at 04:48:48PM +0530, Shashank Sharma wrote:
> >> LSPCON chips can't pick the HDMI AVI infoframes from direct link.
> >> In order to pass AVI infoframes from display controller to LSPCON,
> >> we have to write infoframe packets into vendor specified AUX address.
> >>
> >> Also, LSPCON vendors provide AUX offsets, to inform the LSPCON
> >> chip that the AVI IF packets are written, so that the firmware
> >> can pick it up and apply.
> >>
> >> This patch adds function to write AVI infoframes for both MCA as
> >> well as Parade Tech LSPCON chips. These two vendors provide different
> >> methods for writing infoframes, so this patch contains two different
> >> functions, one for each.
> > Seems to me that we should also be checking the receiver cap for the
> > 444->420 conversion support, and enable it in the PROTOCOL_CONVERTER
> > DPCD register. Or are these LSPCON things even ignoring that part of the
> > spec?
> Yes, LSPCON just needs the YCBCR444 input, and info frames for 420, and 
> it would take care of
> 444->420 conversion in FW.

So it snoops the AVI infoframe we write to it to figure out that it has
to do the 444->420 downsampling?

> Also, its a part of LSPCON specs, that it has 
> to have 420 output capability.
> 
> - Shashank
> >
> >> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> >> Cc: Imre Deak <imre.deak at intel.com>
> >> Signed-off-by: Shashank Sharma <shashank.sharma at intel.com>
> >> ---
> >>   drivers/gpu/drm/i915/intel_ddi.c    |   8 ++
> >>   drivers/gpu/drm/i915/intel_drv.h    |   3 +
> >>   drivers/gpu/drm/i915/intel_lspcon.c | 174 ++++++++++++++++++++++++++++++++++++
> >>   3 files changed, 185 insertions(+)
> >>
> >> diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
> >> index f691710..944d9d5 100644
> >> --- a/drivers/gpu/drm/i915/intel_ddi.c
> >> +++ b/drivers/gpu/drm/i915/intel_ddi.c
> >> @@ -2068,6 +2068,14 @@ void intel_ddi_set_avi_infoframe(struct drm_encoder *encoder,
> >>   					   rgb_qrange_limited,
> >>   					   rgb_qrange_selectable);
> >>   
> >> +	if (crtc_state->lspcon_active) {
> >> +		struct intel_lspcon *lspcon = enc_to_intel_lspcon(encoder);
> >> +
> >> +		/* LSPCON writes infoframes via AUX */
> >> +		lspcon->write_infoframe(encoder, crtc_state, &frame);
> >> +		return;
> >> +	}
> >> +
> >>   	intel_write_infoframe(encoder, crtc_state, &frame);
> >>   }
> >>   
> >> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> >> index fad9a53..3e686d2 100644
> >> --- a/drivers/gpu/drm/i915/intel_drv.h
> >> +++ b/drivers/gpu/drm/i915/intel_drv.h
> >> @@ -1079,6 +1079,9 @@ struct intel_lspcon {
> >>   	/* AVI IF setup function for LSPCON */
> >>   	void (*set_infoframes)(struct drm_encoder *encoder,
> >>   				const struct intel_crtc_state *crtc_state);
> >> +	void (*write_infoframe)(struct drm_encoder *encoder,
> >> +				const struct intel_crtc_state *crtc_state,
> >> +				union hdmi_infoframe *frame);
> >>   };
> >>   
> >>   struct intel_digital_port {
> >> diff --git a/drivers/gpu/drm/i915/intel_lspcon.c b/drivers/gpu/drm/i915/intel_lspcon.c
> >> index 53ddd39..01fddf7 100644
> >> --- a/drivers/gpu/drm/i915/intel_lspcon.c
> >> +++ b/drivers/gpu/drm/i915/intel_lspcon.c
> >> @@ -31,6 +31,18 @@
> >>   #define LSPCON_VENDOR_PARADE_OUI 0x001CF8
> >>   #define LSPCON_VENDOR_MCA_OUI 0x0060AD
> >>   
> >> +/* AUX addresses to write AVI IF into */
> >> +#define LSPCON_MCA_AVI_IF_WRITE_OFFSET 0x5C0
> >> +#define LSPCON_MCA_AVI_IF_CTRL 0x5DF
> >> +#define  LSPCON_MCA_AVI_IF_KICKOFF (1 << 0)
> >> +#define  LSPCON_MCA_AVI_IF_HANDLED (1 << 1)
> >> +
> >> +#define LSPCON_PARADE_AVI_IF_WRITE_OFFSET 0x516
> >> +#define LSPCON_PARADE_AVI_IF_CTRL 0x51E
> >> +#define  LSPCON_PARADE_AVI_IF_KICKOFF (1 << 7)
> >> +#define LSPCON_PARADE_AVI_IF_STATUS 0x51F
> >> +#define  LSPCON_PARADE_AVI_IF_HANDLED (2 << 6)
> >> +
> >>   static struct intel_dp *lspcon_to_intel_dp(struct intel_lspcon *lspcon)
> >>   {
> >>   	struct intel_digital_port *dig_port =
> >> @@ -217,6 +229,167 @@ bool lspcon_ycbcr420_config(struct drm_connector *connector,
> >>   	return false;
> >>   }
> >>   
> >> +static bool _lspcon_write_infoframe_parade(struct drm_dp_aux *aux,
> >> +					   uint8_t *buffer, ssize_t len)
> >> +{
> >> +	u8 avi_if_ctrl;
> >> +	u8 avi_if_status;
> >> +	u8 count = 0;
> >> +	u8 retry = 5;
> >> +	u8 avi_buf[8] = {0, };
> >> +	uint16_t reg;
> >> +	ssize_t ret;
> >> +
> >> +	while (count++ < 4) {
> >> +
> >> +		do {
> >> +			/* Is LSPCON FW ready */
> >> +			reg = LSPCON_PARADE_AVI_IF_CTRL;
> >> +			ret = drm_dp_dpcd_read(aux, reg, &avi_if_ctrl, 1);
> >> +			if (ret < 0) {
> >> +				DRM_ERROR("DPCD read failed, add:0x%x\n", reg);
> >> +				return false;
> >> +			}
> >> +
> >> +			if (avi_if_ctrl & LSPCON_PARADE_AVI_IF_KICKOFF)
> >> +				break;
> >> +			usleep_range(100, 200);
> >> +		} while (--retry);
> >> +
> >> +		if (!(avi_if_ctrl & LSPCON_PARADE_AVI_IF_KICKOFF)) {
> >> +			DRM_ERROR("LSPCON FW not ready for infoframes\n");
> >> +			return false;
> >> +		}
> >> +
> >> +		/*
> >> +		 * AVI Infoframe contains 31 bytes of data:
> >> +		 *	HB0 to HB2   (3 bytes header)
> >> +		 *	PB0 to PB27 (28 bytes data)
> >> +		 * As per Parade spec, while sending first block (8bytes),
> >> +		 * byte 0 is kept for request token no, and byte1 - byte7
> >> +		 * contain frame data. So we have to pack frame like this:
> >> +		 *	first block of 8 bytes: <token> <HB0-HB2> <PB0-PB3>
> >> +		 *	next 3 blocks: <PB4-PB27>
> >> +		 */
> >> +		if (count)
> >> +			memcpy(avi_buf, buffer + count * 8 - 1, 8);
> >> +		else {
> >> +			avi_buf[0] = 1;
> >> +			memcpy(&avi_buf[1], buffer, 7);
> >> +		}
> >> +
> >> +		/* Write 8 bytes of data at a time */
> >> +		reg = LSPCON_PARADE_AVI_IF_WRITE_OFFSET;
> >> +		ret = drm_dp_dpcd_write(aux, reg, avi_buf, 8);
> >> +		if (ret < 0) {
> >> +			DRM_ERROR("DPCD write failed, add:0x%x\n", reg);
> >> +			return false;
> >> +		}
> >> +
> >> +		/*
> >> +		 * While sending a block of 8 byes, we need to inform block
> >> +		 * number to FW, by programming bits[1:0] of ctrl reg with
> >> +		 * block number
> >> +		 */
> >> +		avi_if_ctrl = 0x80 + count;
> >> +		reg = LSPCON_PARADE_AVI_IF_CTRL;
> >> +		ret = drm_dp_dpcd_write(aux, reg, &avi_if_ctrl, 1);
> >> +		if (ret < 0) {
> >> +			DRM_ERROR("DPCD write failed, add:0x%x\n", reg);
> >> +			return false;
> >> +		}
> >> +	}
> >> +
> >> +	/* Check LSPCON FW status */
> >> +	reg = LSPCON_PARADE_AVI_IF_STATUS;
> >> +	ret = drm_dp_dpcd_read(aux, reg, &avi_if_status, 1);
> >> +	if (ret < 0) {
> >> +		DRM_ERROR("DPCD write failed, address 0x%x\n", reg);
> >> +		return false;
> >> +	}
> >> +
> >> +	if (avi_if_status & LSPCON_PARADE_AVI_IF_HANDLED)
> >> +		DRM_DEBUG_KMS("AVI IF handled by FW\n");
> >> +
> >> +	return true;
> >> +}
> >> +
> >> +static bool _lspcon_write_infoframe_mca(struct drm_dp_aux *aux,
> >> +					uint8_t *buffer, ssize_t len)
> >> +{
> >> +	int ret;
> >> +	uint32_t val = 0;
> >> +	uint16_t reg;
> >> +	uint8_t *data = buffer;
> >> +
> >> +	reg = LSPCON_MCA_AVI_IF_WRITE_OFFSET;
> >> +	while (val < len) {
> >> +		ret = drm_dp_dpcd_write(aux, reg, data, 1);
> >> +		if (ret < 0) {
> >> +			DRM_ERROR("DPCD write failed, add:0x%x\n", reg);
> >> +			return false;
> >> +		}
> >> +		val++; reg++; data++;
> >> +	}
> >> +
> >> +	val = 0;
> >> +	reg = LSPCON_MCA_AVI_IF_CTRL;
> >> +	ret = drm_dp_dpcd_read(aux, reg, &val, 1);
> >> +	if (ret < 0) {
> >> +		DRM_ERROR("DPCD read failed, address 0x%x\n", reg);
> >> +		return false;
> >> +	}
> >> +
> >> +	/* Indicate LSPCON chip about infoframe, clear bit 1 and set bit 0 */
> >> +	val &= ~LSPCON_MCA_AVI_IF_HANDLED;
> >> +	val |= LSPCON_MCA_AVI_IF_KICKOFF;
> >> +
> >> +	ret = drm_dp_dpcd_write(aux, reg, &val, 1);
> >> +	if (ret < 0) {
> >> +		DRM_ERROR("DPCD read failed, address 0x%x\n", reg);
> >> +		return false;
> >> +	}
> >> +
> >> +	val = 0;
> >> +	ret = drm_dp_dpcd_read(aux, reg, &val, 1);
> >> +	if (ret < 0) {
> >> +		DRM_ERROR("DPCD read failed, address 0x%x\n", reg);
> >> +		return false;
> >> +	}
> >> +
> >> +	if (val == LSPCON_MCA_AVI_IF_HANDLED)
> >> +		DRM_DEBUG_KMS("AVI IF handled by FW\n");
> >> +
> >> +	return true;
> >> +}
> >> +
> >> +void lspcon_write_infoframe(struct drm_encoder *encoder,
> >> +				  const struct intel_crtc_state *crtc_state,
> >> +				  union hdmi_infoframe *frame)
> >> +{
> >> +	bool ret;
> >> +	ssize_t len;
> >> +	uint8_t buf[VIDEO_DIP_DATA_SIZE];
> >> +	struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
> >> +	struct intel_lspcon *lspcon = enc_to_intel_lspcon(encoder);
> >> +
> >> +	len = hdmi_infoframe_pack(frame, buf, sizeof(buf));
> >> +	if (len < 0) {
> >> +		DRM_ERROR("Failed to pack AVI IF\n");
> >> +		return;
> >> +	}
> >> +
> >> +	if (lspcon->vendor == LSPCON_VENDOR_MCA)
> >> +		ret = _lspcon_write_infoframe_mca(&intel_dp->aux, buf, len);
> >> +	else
> >> +		ret = _lspcon_write_infoframe_parade(&intel_dp->aux, buf, len);
> >> +
> >> +	if (!ret)
> >> +		DRM_ERROR("Failed to write AVI infoframes\n");
> >> +	else
> >> +		DRM_DEBUG_DRIVER("AVI infoframes updated successfully\n");
> >> +}
> >> +
> >>   void lspcon_resume(struct intel_lspcon *lspcon)
> >>   {
> >>   	enum drm_lspcon_mode expected_mode;
> >> @@ -282,6 +455,7 @@ bool lspcon_init(struct intel_digital_port *intel_dig_port)
> >>   
> >>   	connector->ycbcr_420_allowed = true;
> >>   	lspcon->set_infoframes = intel_ddi_set_avi_infoframe;
> >> +	lspcon->write_infoframe = lspcon_write_infoframe;
> >>   	drm_dp_read_desc(&dp->aux, &dp->desc, drm_dp_is_branch(dp->dpcd));
> >>   
> >>   	DRM_DEBUG_KMS("Success: LSPCON init\n");
> >> -- 
> >> 2.7.4

-- 
Ville Syrjälä
Intel OTC


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