target/linux/bcm27xx/patches-5.15/950-0634-drm-vc4-hdmi-Always-try-to-have-the-highest-bpc.patch

   1 From 5194c69ca3e4af8c3a6ffc77e5eb1ee0a62a6bbe Mon Sep 17 00:00:00 2001
   2 From: Maxime Ripard <maxime@cerno.tech>
   3 Date: Fri, 10 Dec 2021 15:29:56 +0100
   4 Subject: [PATCH] drm/vc4: hdmi: Always try to have the highest bpc
   5
   6 Currently we take the max_bpc property as the bpc value and do not try
   7 anything else.
   8
   9 However, what the other drivers seem to be doing is that they would try
  10 with the highest bpc allowed by the max_bpc property and the hardware
  11 capabilities, test if it results in an acceptable configuration, and if
  12 not decrease the bpc and try again.
  13
  14 Let's use the same logic.
  15
  16 Signed-off-by: Maxime Ripard <maxime@cerno.tech>
  17 ---
  18  drivers/gpu/drm/vc4/vc4_hdmi.c | 44 ++++++++++++++++++++++++++++++----
  19  drivers/gpu/drm/vc4/vc4_hdmi.h |  4 +++-
  20  2 files changed, 43 insertions(+), 5 deletions(-)
  21
  22 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c
  23 +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
  24 @@ -357,6 +357,7 @@ vc4_hdmi_connector_duplicate_state(struc
  25                 return NULL;
  26
  27         new_state->pixel_rate = vc4_state->pixel_rate;
  28 +       new_state->output_bpc = vc4_state->output_bpc;
  29         __drm_atomic_helper_connector_duplicate_state(connector, &new_state->base);
  30
  31         return &new_state->base;
  32 @@ -914,6 +915,8 @@ static void vc5_hdmi_set_timings(struct
  33                                  struct drm_connector_state *state,
  34                                  struct drm_display_mode *mode)
  35  {
  36 +       const struct vc4_hdmi_connector_state *vc4_state =
  37 +               conn_state_to_vc4_hdmi_conn_state(state);
  38         bool hsync_pos = mode->flags & DRM_MODE_FLAG_PHSYNC;
  39         bool vsync_pos = mode->flags & DRM_MODE_FLAG_PVSYNC;
  40         bool interlaced = mode->flags & DRM_MODE_FLAG_INTERLACE;
  41 @@ -962,7 +965,7 @@ static void vc5_hdmi_set_timings(struct
  42         HDMI_WRITE(HDMI_VERTB0, vertb_even);
  43         HDMI_WRITE(HDMI_VERTB1, vertb);
  44
  45 -       switch (state->max_bpc) {
  46 +       switch (vc4_state->output_bpc) {
  47         case 12:
  48                 gcp = 6;
  49                 gcp_en = true;
  50 @@ -1252,9 +1255,11 @@ static void vc4_hdmi_encoder_atomic_mode
  51                                              struct drm_connector_state *conn_state)
  52  {
  53         struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
  54 +       struct vc4_hdmi_connector_state *vc4_state =
  55 +               conn_state_to_vc4_hdmi_conn_state(conn_state);
  56
  57         mutex_lock(&vc4_hdmi->mutex);
  58 -       vc4_hdmi->output_bpc = conn_state->max_bpc;
  59 +       vc4_hdmi->output_bpc = vc4_state->output_bpc;
  60         memcpy(&vc4_hdmi->saved_adjusted_mode,
  61                &crtc_state->adjusted_mode,
  62                sizeof(vc4_hdmi->saved_adjusted_mode));
  63 @@ -1309,6 +1314,38 @@ vc4_hdmi_encoder_compute_clock(const str
  64         return 0;
  65  }
  66
  67 +static int
  68 +vc4_hdmi_encoder_compute_config(const struct vc4_hdmi *vc4_hdmi,
  69 +                               struct vc4_hdmi_connector_state *vc4_state,
  70 +                               const struct drm_display_mode *mode)
  71 +{
  72 +       struct drm_connector_state *conn_state = &vc4_state->base;
  73 +       unsigned int max_bpc = clamp_t(unsigned int, conn_state->max_bpc, 8, 12);
  74 +       unsigned int bpc;
  75 +       int ret;
  76 +
  77 +       for (bpc = max_bpc; bpc >= 8; bpc -= 2) {
  78 +               drm_dbg(dev, "Trying with a %d bpc output\n", bpc);
  79 +
  80 +               ret = vc4_hdmi_encoder_compute_clock(vc4_hdmi, vc4_state,
  81 +                                                    mode, bpc);
  82 +               if (ret)
  83 +                       continue;
  84 +
  85 +               vc4_state->output_bpc = bpc;
  86 +
  87 +               drm_dbg(dev,
  88 +                       "Mode %ux%u @ %uHz: Found configuration: bpc: %u, clock: %llu\n",
  89 +                       mode->hdisplay, mode->vdisplay, drm_mode_vrefresh(mode),
  90 +                       vc4_state->output_bpc,
  91 +                       vc4_state->pixel_rate);
  92 +
  93 +               break;
  94 +       }
  95 +
  96 +       return ret;
  97 +}
  98 +
  99  #define WIFI_2_4GHz_CH1_MIN_FREQ       2400000000ULL
 100  #define WIFI_2_4GHz_CH1_MAX_FREQ       2422000000ULL
 101
 102 @@ -1343,8 +1380,7 @@ static int vc4_hdmi_encoder_atomic_check
 103                 pixel_rate = mode->clock * 1000;
 104         }
 105
 106 -       ret = vc4_hdmi_encoder_compute_clock(vc4_hdmi, vc4_state, mode,
 107 -                                            conn_state->max_bpc);
 108 +       ret = vc4_hdmi_encoder_compute_config(vc4_hdmi, vc4_state, mode);
 109         if (ret)
 110                 return ret;
 111
 112 --- a/drivers/gpu/drm/vc4/vc4_hdmi.h
 113 +++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
 114 @@ -222,7 +222,8 @@ struct vc4_hdmi {
 115         bool scdc_enabled;
 116
 117         /**
 118 -        * @output_bpc: BPC currently being used. Protected by @mutex.
 119 +        * @output_bpc: Copy of @vc4_connector_state.output_bpc for use
 120 +        * outside of KMS hooks. Protected by @mutex.
 121          */
 122         unsigned int output_bpc;
 123
 124 @@ -252,6 +253,7 @@ encoder_to_vc4_hdmi(struct drm_encoder *
 125  struct vc4_hdmi_connector_state {
 126         struct drm_connector_state      base;
 127         unsigned long long              pixel_rate;
 128 +       unsigned int                    output_bpc;
 129  };
 130
 131  static inline struct vc4_hdmi_connector_state *