[Intel-gfx] [PATCH v3] drm/i915/display: Enable DP Display Audio WA
Jani Nikula
jani.nikula at linux.intel.com
Tue Apr 7 13:55:38 UTC 2020
On Tue, 07 Apr 2020, Uma Shankar <uma.shankar at intel.com> wrote:
> For certain DP VDSC bpp settings, hblank asserts before hblank_early,
> leading to a bad audio state. Driver need to program "hblank early
> enable" and "samples per line" parameters in AUDIO_CONFIG_BE
> register.
>
> This is Display Audio WA #1406928334 for 4k+VDSC usecase
> applicable on DP encoders. Implemented the same.
>
> v2: Fixed build failures on 32bit machine.
>
> v3: Dropped u64, added helpers for sample room calculation,
> other general comments as per Jani Nikula's feedback.
> Also fixed connector type check (spotted by Anshuman)
>
> Signed-off-by: Uma Shankar <uma.shankar at intel.com>
> ---
> drivers/gpu/drm/i915/display/intel_audio.c | 146 +++++++++++++++++++++
> drivers/gpu/drm/i915/i915_reg.h | 16 +++
> 2 files changed, 162 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_audio.c b/drivers/gpu/drm/i915/display/intel_audio.c
> index 950160f1a89f..56fd17b65ce0 100644
> --- a/drivers/gpu/drm/i915/display/intel_audio.c
> +++ b/drivers/gpu/drm/i915/display/intel_audio.c
> @@ -512,6 +512,148 @@ static void hsw_audio_codec_disable(struct intel_encoder *encoder,
> mutex_unlock(&dev_priv->av_mutex);
> }
>
> +/* Add a factor to take care of rounding and truncations */
> +#define ROUNDING_FACTOR 10000
> +static int set_hblank_early_enable_config(struct intel_encoder *encoder,
> + const struct intel_crtc_state *crtc_state,
> + u32 *val)
> +{
> + struct drm_i915_private *i915 = to_i915(encoder->base.dev);
> + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> + enum pipe pipe = crtc->pipe;
> + u32 link_clks_available, link_clks_required;
> + u32 tu_data, tu_line, link_clks_active;
> + u32 hblank_rise, hblank_early_prog;
> + u32 h_active, h_total, hblank_delta, pixel_clk, v_total;
> + u32 fec_coeff, refresh_rate, cdclk;
> +
> + h_active = crtc_state->hw.adjusted_mode.hdisplay;
> + h_total = crtc_state->hw.adjusted_mode.htotal;
> + v_total = crtc_state->hw.adjusted_mode.vtotal;
> + hblank_rise = crtc_state->hw.adjusted_mode.hsync_start;
> + pixel_clk = crtc_state->hw.adjusted_mode.clock;
> + refresh_rate = crtc_state->hw.adjusted_mode.vrefresh;
> + cdclk = i915->cdclk.hw.cdclk;
> + /* fec= 0.972261, using rounding multiplier of 1000000 */
> + fec_coeff = 972261;
> +
> + if (!(h_active && crtc_state->port_clock && crtc_state->lane_count &&
> + crtc_state->pipe_bpp && cdclk)) {
> + drm_err(&i915->drm, "Null Parameters received\n");
> + WARN_ON(1);
> + return -EINVAL;
> + }
> +
> + drm_dbg_kms(&i915->drm, "h_active = %u link_clk = %u :"
> + "lanes = %u vdsc_bpp = %u cdclk = %u\n",
> + h_active, crtc_state->port_clock, crtc_state->lane_count,
> + crtc_state->pipe_bpp, cdclk);
> +
> + link_clks_available = ((((h_total - h_active) *
> + ((crtc_state->port_clock * ROUNDING_FACTOR) /
> + pixel_clk)) / ROUNDING_FACTOR) - 28);
> +
> + link_clks_required = DIV_ROUND_UP(192000, (refresh_rate *
> + v_total)) * ((48 /
> + crtc_state->lane_count) + 2);
> +
> + if (link_clks_available > link_clks_required)
> + hblank_delta = 32;
> + else
> + hblank_delta = DIV_ROUND_UP(((((5 * ROUNDING_FACTOR) /
> + crtc_state->port_clock) + ((5 *
> + ROUNDING_FACTOR) /
> + cdclk)) * pixel_clk),
> + ROUNDING_FACTOR);
> +
> + tu_data = (pixel_clk * crtc_state->pipe_bpp * 8) /
> + ((crtc_state->port_clock *
> + crtc_state->lane_count * fec_coeff) / 1000000);
> + tu_line = (((h_active * crtc_state->port_clock * fec_coeff) /
> + 1000000) / (64 * pixel_clk));
> + link_clks_active = (tu_line - 1) * 64 + tu_data;
> +
> + hblank_rise = ((link_clks_active + 6 * DIV_ROUND_UP(link_clks_active,
> + 250) + 4) * ((pixel_clk * ROUNDING_FACTOR) /
> + crtc_state->port_clock)) / ROUNDING_FACTOR;
> +
> + hblank_early_prog = h_active - hblank_rise + hblank_delta;
> +
> + if (hblank_early_prog < 32) {
> + *val &= ~HBLANK_START_COUNT_MASK(pipe);
> + *val |= HBLANK_START_COUNT(pipe, HBLANK_START_COUNT_32);
> + } else if (hblank_early_prog < 64) {
> + *val &= ~HBLANK_START_COUNT_MASK(pipe);
> + *val |= HBLANK_START_COUNT(pipe, HBLANK_START_COUNT_64);
> + } else if (hblank_early_prog < 96) {
> + *val &= ~HBLANK_START_COUNT_MASK(pipe);
> + *val |= HBLANK_START_COUNT(pipe, HBLANK_START_COUNT_96);
> + } else {
> + *val &= ~HBLANK_START_COUNT_MASK(pipe);
> + *val |= HBLANK_START_COUNT(pipe, HBLANK_START_COUNT_128);
> + }
> +
> + return 0;
> +}
> +
> +static void set_sample_room_config(const struct intel_crtc_state *crtc_state,
> + u32 *val)
> +{
> + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> + enum pipe pipe = crtc->pipe;
> + u32 h_active, h_total, pixel_clk;
> + u32 samples_room;
> +
> + h_active = crtc_state->hw.adjusted_mode.hdisplay;
> + h_total = crtc_state->hw.adjusted_mode.htotal;
> + pixel_clk = crtc_state->hw.adjusted_mode.clock;
> +
> + samples_room = ((((h_total - h_active) * ((crtc_state->port_clock *
> + ROUNDING_FACTOR) / pixel_clk)) /
> + ROUNDING_FACTOR) - 12) / ((48 /
> + crtc_state->lane_count) + 2);
> +
> + if (samples_room < 3) {
> + *val &= ~NUMBER_SAMPLES_PER_LINE_MASK(pipe);
> + *val |= NUMBER_SAMPLES_PER_LINE(pipe, samples_room);
> + } else {
> + *val &= ~NUMBER_SAMPLES_PER_LINE_MASK(pipe);
> + *val |= NUMBER_SAMPLES_PER_LINE(pipe, 0x0);
> + }
> +}
> +
> +static void enable_audio_dsc_wa(struct intel_encoder *encoder,
> + const struct intel_crtc_state *crtc_state)
> +{
> + struct drm_i915_private *i915 = to_i915(encoder->base.dev);
> + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> + enum pipe pipe = crtc->pipe;
> + u32 val;
> +
> + if (INTEL_GEN(i915) < 11)
> + return;
> +
> + val = intel_de_read(i915, AUD_CONFIG_BE);
> +
> + if (INTEL_GEN(i915) == 11)
> + val |= HBLANK_EARLY_ENABLE_ICL(pipe);
> + else if (INTEL_GEN(i915) >= 12)
> + val |= HBLANK_EARLY_ENABLE_TGL(pipe);
> +
> + if (crtc_state->dsc.compression_enable &&
> + (crtc_state->hw.adjusted_mode.hdisplay >= 3840 &&
> + crtc_state->hw.adjusted_mode.vdisplay >= 2160)) {
> + if (set_hblank_early_enable_config(encoder, crtc_state, &val))
> + return;
> +
> + set_sample_room_config(crtc_state, &val);
Communication is hard. I tried to imply that you'd add helpers that
*return* the values. Then the computations get moved to the helpers, yet
the modifications of the local variable val remain here. The split is
clear, and easy to follow.
BR,
Jani.
> + }
> +
> + intel_de_write(i915, AUD_CONFIG_BE, val);
> +}
> +
> +#undef ROUNDING_FACTOR
> +
> static void hsw_audio_codec_enable(struct intel_encoder *encoder,
> const struct intel_crtc_state *crtc_state,
> const struct drm_connector_state *conn_state)
> @@ -529,6 +671,10 @@ static void hsw_audio_codec_enable(struct intel_encoder *encoder,
>
> mutex_lock(&dev_priv->av_mutex);
>
> + /* Enable Audio WA for 4k DSC usecases */
> + if (intel_crtc_has_type(crtc_state, INTEL_OUTPUT_DP))
> + enable_audio_dsc_wa(encoder, crtc_state);
> +
> /* Enable audio presence detect, invalidate ELD */
> tmp = intel_de_read(dev_priv, HSW_AUD_PIN_ELD_CP_VLD);
> tmp |= AUDIO_OUTPUT_ENABLE(cpu_transcoder);
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 8cebb7a86b8c..f72ea2c2a8e3 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -9395,6 +9395,22 @@ enum {
> #define AUD_PIN_BUF_CTL _MMIO(0x48414)
> #define AUD_PIN_BUF_ENABLE REG_BIT(31)
>
> +/* Display Audio Config Reg */
> +#define AUD_CONFIG_BE _MMIO(0x65ef0)
> +#define HBLANK_EARLY_ENABLE_ICL(pipe) (0x1 << (20 - (pipe)))
> +#define HBLANK_EARLY_ENABLE_TGL(pipe) (0x1 << (24 + (pipe)))
> +#define HBLANK_START_COUNT_MASK(pipe) (0x7 << (3 + ((pipe) * 6)))
> +#define HBLANK_START_COUNT(pipe, val) (((val) & 0x7) << (3 + ((pipe)) * 6))
> +#define NUMBER_SAMPLES_PER_LINE_MASK(pipe) (0x3 << ((pipe) * 6))
> +#define NUMBER_SAMPLES_PER_LINE(pipe, val) (((val) & 0x3) << ((pipe) * 6))
> +
> +#define HBLANK_START_COUNT_8 0
> +#define HBLANK_START_COUNT_16 1
> +#define HBLANK_START_COUNT_32 2
> +#define HBLANK_START_COUNT_64 3
> +#define HBLANK_START_COUNT_96 4
> +#define HBLANK_START_COUNT_128 5
> +
> /*
> * HSW - ICL power wells
> *
--
Jani Nikula, Intel Open Source Graphics Center
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