[RFC 11/13] drm/i915: Read DSC capabilities of the HDMI2.1 PCON encoder
Shankar, Uma
uma.shankar at intel.com
Sun Oct 18 23:32:11 UTC 2020
> -----Original Message-----
> From: Nautiyal, Ankit K <ankit.k.nautiyal at intel.com>
> Sent: Thursday, October 15, 2020 4:23 PM
> To: intel-gfx at lists.freedesktop.org
> Cc: dri-devel at lists.freedesktop.org; Shankar, Uma <uma.shankar at intel.com>;
> Kulkarni, Vandita <vandita.kulkarni at intel.com>; ville.syrjala at linux.intel.com;
> Sharma, Swati2 <swati2.sharma at intel.com>
> Subject: [RFC 11/13] drm/i915: Read DSC capabilities of the HDMI2.1 PCON
> encoder
>
> This patch adds a helper function to read the DSC capabilities of the
> HDMI2.1 PCon encoder. It also adds a new structure to store these caps, which
> can then be used to get the PPS parameters for PCON-HDMI2.1 sink pair. Which
> inturn will be used to take a call to override the existing PPS-metadata, by either
> writing the entire new PPS metadata, or by writing only the PPS override
> parameters.
>
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
> ---
> .../drm/i915/display/intel_display_types.h | 16 ++
> drivers/gpu/drm/i915/display/intel_dp.c | 178 ++++++++++++++++++
> 2 files changed, 194 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h
> b/drivers/gpu/drm/i915/display/intel_display_types.h
> index 6c69922313d6..23282695a47f 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> @@ -1292,6 +1292,21 @@ struct intel_dp_pcon_frl {
> int trained_rate_gbps;
> };
>
> +struct intel_dp_pcon_dsc {
> + bool enc_support;
> + bool pps_override_support;
> + bool blk_prediction_support;
> + u8 version_major;
> + u8 version_minor;
> + u8 color_fmt_mask;
> + u8 color_depth_mask;
> + u8 max_slices;;
> + u8 max_slice_width;
> + u8 line_buf_bit_depth;
> + u8 bpp_precision_incr;
> + int rc_buf_size;
> +};
> +
> struct intel_dp {
> i915_reg_t output_reg;
> u32 DP;
> @@ -1415,6 +1430,7 @@ struct intel_dp {
> bool hobl_active;
>
> struct intel_dp_pcon_frl frl;
> + struct intel_dp_pcon_dsc pcon_dsc;
> };
>
> enum lspcon_vendor {
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> b/drivers/gpu/drm/i915/display/intel_dp.c
> index e6c4cb844e37..b4f8abaea607 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -3882,6 +3882,182 @@ cpt_set_link_train(struct intel_dp *intel_dp,
> intel_de_posting_read(dev_priv, intel_dp->output_reg); }
>
> +void intel_dp_get_pcon_dsc_cap(struct intel_dp *intel_dp) {
> + u8 buf;
> + u8 rc_buf_blk_size;
> + u8 max_slices = 0;
> +
> + struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> + struct intel_dp_pcon_dsc *pcon_dsc = &intel_dp->pcon_dsc;
> +
> + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_PCON_DSC_ENCODER, &buf)
> < 0) {
> + drm_err(&i915->drm, "Failed to read
> DP_PCON_DSC_ENCODER\n");
> + return;
> + }
> + pcon_dsc->enc_support = buf & DP_PCON_DSC_ENCODER_SUPPORTED;
> + pcon_dsc->pps_override_support = buf &
> DP_PCON_DSC_PPS_ENC_OVERRIDE;
> +
> + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_PCON_DSC_VERSION, &buf)
> < 0) {
> + drm_err(&i915->drm, "Failed to read
> DP_PCON_DSC_VERSION\n");
> + return;
If we fail here or in any of the subsequent calls below shouldn't we reset the dsc params saying DSC not
supported. Else we may return with ex.
pcon_dsc->enc_support = buf & DP_PCON_DSC_ENCODER_SUPPORTED
which would ideally not be right.
> + }
> + pcon_dsc->version_major = (buf & DP_PCON_DSC_MAJOR_MASK) >>
> + DP_PCON_DSC_MAJOR_SHIFT;
> + pcon_dsc->version_minor = (buf & DP_PCON_DSC_MINOR_MASK) >>
> + DP_PCON_DSC_MINOR_SHIFT;
> +
> + if (drm_dp_dpcd_readb(&intel_dp->aux,
> DP_PCON_DSC_RC_BUF_BLK_INFO, &buf) < 0) {
> + drm_err(&i915->drm, "Failed to read
> DP_PCON_DSC_RC_BUF_BLK_INFO\n");
> + return;
> + }
> +
> + switch (buf & DP_PCON_DSC_RC_BUF_BLK_SIZE) {
> + case DP_PCON_DSC_RC_BUF_BLK_1KB :
> + rc_buf_blk_size = 1;
> + break;
> + case DP_PCON_DSC_RC_BUF_BLK_4KB :
> + rc_buf_blk_size = 4;
> + break;
> + case DP_PCON_DSC_RC_BUF_BLK_16KB :
> + rc_buf_blk_size = 16;
> + break;
> + case DP_PCON_DSC_RC_BUF_BLK_64KB :
> + rc_buf_blk_size = 64;
> + break;
> + default :
> + rc_buf_blk_size = 0;
> + }
It would be good if you create sub-functions for each of these aspects to make it more readable.
> + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_PCON_DSC_RC_BUF_SIZE,
> &buf) < 0) {
> + drm_err(&i915->drm, "Failed to read
> DP_PCON_DSC_RC_BUF_SIZE\n");
> + return;
> + }
> + /* storing rc_buf_size in bytes */
> + pcon_dsc->rc_buf_size = (buf + 1) * rc_buf_blk_size * 1024;
> +
> + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_PCON_DSC_SLICE_CAP_2,
> &buf) < 0) {
> + drm_err(&i915->drm, "Failed to read
> DP_PCON_DSC_SLICE_CAP_2\n");
> + return;
> + }
> + if (buf & DP_PCON_DSC_24_PER_DSC_ENC)
> + max_slices = 24;
> + else if (buf & DP_PCON_DSC_20_PER_DSC_ENC)
> + max_slices = 20;
> + else if (buf & DP_PCON_DSC_16_PER_DSC_ENC)
> + max_slices = 16;
> +
> + if (max_slices == 0) {
> + if (drm_dp_dpcd_readb(&intel_dp->aux,
> DP_PCON_DSC_SLICE_CAP_1,
> + &buf) < 0) {
> + drm_err(&i915->drm, "Failed to read
> DP_PCON_DSC_SLICE_CAP_2\n");
Its SLICE_CAP_1.
> + return;
> + }
> +
> + if (buf & DP_PCON_DSC_12_PER_DSC_ENC)
> + max_slices = 12;
> + else if (buf & DP_PCON_DSC_10_PER_DSC_ENC)
> + max_slices = 10;
> + else if (buf & DP_PCON_DSC_8_PER_DSC_ENC)
> + max_slices = 8;
> + else if (buf & DP_PCON_DSC_6_PER_DSC_ENC)
> + max_slices = 6;
> + else if (buf & DP_PCON_DSC_4_PER_DSC_ENC)
> + max_slices = 4;
> + else if (buf & DP_PCON_DSC_2_PER_DSC_ENC)
> + max_slices = 2;
> + else if (buf & DP_PCON_DSC_1_PER_DSC_ENC)
> + max_slices = 1;
Use switch here as well.
> + }
> +
> + pcon_dsc->max_slices = max_slices;
> +
> + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_PCON_DSC_BUF_BIT_DEPTH,
> &buf) < 0) {
> + drm_err(&i915->drm, "Failed to read
> DP_PCON_DSC_BUF_BIT_DEPTH\n");
> + return;
> + }
> + switch (buf & DP_PCON_DSC_BIT_DEPTH_MASK) {
> + case DP_PCON_DSC_DEPTH_8_BITS :
> + pcon_dsc->line_buf_bit_depth = 8;
> + break;
> + case DP_PCON_DSC_DEPTH_9_BITS :
> + pcon_dsc->line_buf_bit_depth = 9;
> + break;
> + case DP_PCON_DSC_DEPTH_10_BITS :
> + pcon_dsc->line_buf_bit_depth = 10;
> + break;
> + case DP_PCON_DSC_DEPTH_11_BITS :
> + pcon_dsc->line_buf_bit_depth = 11;
> + break;
> + case DP_PCON_DSC_DEPTH_12_BITS :
> + pcon_dsc->line_buf_bit_depth = 12;
> + break;
> + case DP_PCON_DSC_DEPTH_13_BITS :
> + pcon_dsc->line_buf_bit_depth = 13;
> + break;
> + case DP_PCON_DSC_DEPTH_14_BITS :
> + pcon_dsc->line_buf_bit_depth = 14;
> + break;
> + case DP_PCON_DSC_DEPTH_15_BITS :
> + pcon_dsc->line_buf_bit_depth = 15;
> + break;
> + case DP_PCON_DSC_DEPTH_16_BITS :
> + pcon_dsc->line_buf_bit_depth = 16;
> + break;
> + default :
> + pcon_dsc->line_buf_bit_depth = 0;
> + }
> +
> + if (drm_dp_dpcd_readb(&intel_dp->aux,
> DP_PCON_DSC_BLOCK_PREDICTION, &buf) < 0) {
> + drm_err(&i915->drm, "Failed to read
> DP_PCON_DSC_BLOCK_PREDICTION\n");
> + return;
> + }
> + if (buf && DP_PCON_DSC_BLOCK_PRED_SUPPORT)
> + pcon_dsc->blk_prediction_support = true;
> +
> + if (drm_dp_dpcd_readb(&intel_dp->aux,
> DP_PCON_DSC_ENC_COLOR_FMT_CAP, &buf) < 0) {
> + drm_err(&i915->drm, "Failed to read
> DP_PCON_DSC_ENC_COLOR_FMT_CAP\n");
> + return;
> + }
> + pcon_dsc->color_fmt_mask = buf;
> +
> + if (drm_dp_dpcd_readb(&intel_dp->aux,
> DP_PCON_DSC_ENC_COLOR_DEPTH_CAP, &buf) < 0) {
> + drm_err(&i915->drm, "Failed to read
> DP_PCON_DSC_ENC_COLOR_DEPTH_CAP\n");
> + return;
> + }
> + pcon_dsc->color_depth_mask = buf;
> +
> + if (drm_dp_dpcd_readb(&intel_dp->aux,
> DP_PCON_DSC_MAX_SLICE_WIDTH, &buf) < 0) {
> + drm_err(&i915->drm, "Failed to read
> DP_PCON_DSC_MAX_SLICE_WIDTH\n");
> + return;
> + }
> + pcon_dsc->max_slice_width = buf;;
> +
> + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_PCON_DSC_BPP_INCR, &buf)
> < 0) {
> + drm_err(&i915->drm, "Failed to read
> DP_PCON_DSC_BPP_INCR\n");
> + return;
> + }
> + switch(buf & DP_PCON_DSC_BPP_INCR_MASK) {
> + case DP_PCON_DSC_ONE_16TH_BPP:
> + pcon_dsc->bpp_precision_incr = 16;
> + break;
> + case DP_PCON_DSC_ONE_8TH_BPP:
> + pcon_dsc->bpp_precision_incr = 8;
> + break;
> + case DP_PCON_DSC_ONE_4TH_BPP:
> + pcon_dsc->bpp_precision_incr = 4;
> + break;
> + case DP_PCON_DSC_ONE_HALF_BPP:
> + pcon_dsc->bpp_precision_incr = 2;
> + break;
> + case DP_PCON_DSC_ONE_BPP:
> + pcon_dsc->bpp_precision_incr = 1;
> + break;
> + default :
> + pcon_dsc->bpp_precision_incr = 0;
> + }
> +}
> +
> static int intel_dp_get_max_rate_gbps(struct intel_dp *intel_dp) {
> int max_link_clock, max_lanes, max_rate_khz, max_rate_gbps; @@ -
> 6659,6 +6835,8 @@ intel_dp_update_dfp(struct intel_dp *intel_dp,
> intel_dp->dfp.max_tmds_clock,
> intel_dp->dfp.pcon_max_frl,
> intel_dp->dfp.sink_max_frl);
> +
> + intel_dp_get_pcon_dsc_cap(intel_dp);
> }
>
> static void
> --
> 2.17.1
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