target/linux/bcm27xx/patches-5.15/950-0628-drm-vc4-hdmi-Define-colorspace-matrices.patch

   1 From cbb71ade28d28e5fcb04171b6be283b150796e7a Mon Sep 17 00:00:00 2001
   2 From: Maxime Ripard <maxime@cerno.tech>
   3 Date: Wed, 13 Jan 2021 11:30:21 +0100
   4 Subject: [PATCH] drm/vc4: hdmi: Define colorspace matrices
   5
   6 The current CSC setup code for the BCM2711 uses a sequence of register
   7 writes to configure the CSC depending on whether we output using a full
   8 or limited range.
   9
  10 However, with the upcoming introduction of the YUV output, we're going
  11 to add new matrices to perform the conversions, so we should switch to
  12 something a bit more flexible that takes the matrix as an argument and
  13 programs the CSC accordingly.
  14
  15 Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
  16 Signed-off-by: Maxime Ripard <maxime@cerno.tech>
  17 ---
  18  drivers/gpu/drm/vc4/vc4_hdmi.c | 79 +++++++++++++++++++++-------------
  19  1 file changed, 50 insertions(+), 29 deletions(-)
  20
  21 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c
  22 +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
  23 @@ -781,6 +781,52 @@ static void vc4_hdmi_csc_setup(struct vc
  24         spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags);
  25  }
  26
  27 +
  28 +/*
  29 + * If we need to output Full Range RGB, then use the unity matrix
  30 + *
  31 + * [ 1      0      0      0]
  32 + * [ 0      1      0      0]
  33 + * [ 0      0      1      0]
  34 + *
  35 + * Matrix is signed 2p13 fixed point, with signed 9p6 offsets
  36 + */
  37 +static const u16 vc5_hdmi_csc_full_rgb_unity[3][4] = {
  38 +       { 0x2000, 0x0000, 0x0000, 0x0000 },
  39 +       { 0x0000, 0x2000, 0x0000, 0x0000 },
  40 +       { 0x0000, 0x0000, 0x2000, 0x0000 },
  41 +};
  42 +
  43 +/*
  44 + * CEA VICs other than #1 require limited range RGB output unless
  45 + * overridden by an AVI infoframe. Apply a colorspace conversion to
  46 + * squash 0-255 down to 16-235. The matrix here is:
  47 + *
  48 + * [ 0.8594 0      0      16]
  49 + * [ 0      0.8594 0      16]
  50 + * [ 0      0      0.8594 16]
  51 + *
  52 + * Matrix is signed 2p13 fixed point, with signed 9p6 offsets
  53 + */
  54 +static const u16 vc5_hdmi_csc_full_rgb_to_limited_rgb[3][4] = {
  55 +       { 0x1b80, 0x0000, 0x0000, 0x0400 },
  56 +       { 0x0000, 0x1b80, 0x0000, 0x0400 },
  57 +       { 0x0000, 0x0000, 0x1b80, 0x0400 },
  58 +};
  59 +
  60 +static void vc5_hdmi_set_csc_coeffs(struct vc4_hdmi *vc4_hdmi,
  61 +                                   const u16 coeffs[3][4])
  62 +{
  63 +       lockdep_assert_held(&vc4_hdmi->hw_lock);
  64 +
  65 +       HDMI_WRITE(HDMI_CSC_12_11, (coeffs[0][1] << 16) | coeffs[0][0]);
  66 +       HDMI_WRITE(HDMI_CSC_14_13, (coeffs[0][3] << 16) | coeffs[0][2]);
  67 +       HDMI_WRITE(HDMI_CSC_22_21, (coeffs[1][1] << 16) | coeffs[1][0]);
  68 +       HDMI_WRITE(HDMI_CSC_24_23, (coeffs[1][3] << 16) | coeffs[1][2]);
  69 +       HDMI_WRITE(HDMI_CSC_32_31, (coeffs[2][1] << 16) | coeffs[2][0]);
  70 +       HDMI_WRITE(HDMI_CSC_34_33, (coeffs[2][3] << 16) | coeffs[2][2]);
  71 +}
  72 +
  73  static void vc5_hdmi_csc_setup(struct vc4_hdmi *vc4_hdmi,
  74                                const struct drm_display_mode *mode)
  75  {
  76 @@ -792,35 +838,10 @@ static void vc5_hdmi_csc_setup(struct vc
  77
  78         HDMI_WRITE(HDMI_VEC_INTERFACE_XBAR, 0x354021);
  79
  80 -       if (!vc4_hdmi_is_full_range_rgb(vc4_hdmi, mode)) {
  81 -               /* CEA VICs other than #1 requre limited range RGB
  82 -                * output unless overridden by an AVI infoframe.
  83 -                * Apply a colorspace conversion to squash 0-255 down
  84 -                * to 16-235.  The matrix here is:
  85 -                *
  86 -                * [ 0.8594 0      0      16]
  87 -                * [ 0      0.8594 0      16]
  88 -                * [ 0      0      0.8594 16]
  89 -                * [ 0      0      0       1]
  90 -                * Matrix is signed 2p13 fixed point, with signed 9p6 offsets
  91 -                */
  92 -               HDMI_WRITE(HDMI_CSC_12_11, (0x0000 << 16) | 0x1b80);
  93 -               HDMI_WRITE(HDMI_CSC_14_13, (0x0400 << 16) | 0x0000);
  94 -               HDMI_WRITE(HDMI_CSC_22_21, (0x1b80 << 16) | 0x0000);
  95 -               HDMI_WRITE(HDMI_CSC_24_23, (0x0400 << 16) | 0x0000);
  96 -               HDMI_WRITE(HDMI_CSC_32_31, (0x0000 << 16) | 0x0000);
  97 -               HDMI_WRITE(HDMI_CSC_34_33, (0x0400 << 16) | 0x1b80);
  98 -       } else {
  99 -               /* Still use the matrix for full range, but make it unity.
 100 -                * Matrix is signed 2p13 fixed point, with signed 9p6 offsets
 101 -                */
 102 -               HDMI_WRITE(HDMI_CSC_12_11, (0x0000 << 16) | 0x2000);
 103 -               HDMI_WRITE(HDMI_CSC_14_13, (0x0000 << 16) | 0x0000);
 104 -               HDMI_WRITE(HDMI_CSC_22_21, (0x2000 << 16) | 0x0000);
 105 -               HDMI_WRITE(HDMI_CSC_24_23, (0x0000 << 16) | 0x0000);
 106 -               HDMI_WRITE(HDMI_CSC_32_31, (0x0000 << 16) | 0x0000);
 107 -               HDMI_WRITE(HDMI_CSC_34_33, (0x0000 << 16) | 0x2000);
 108 -       }
 109 +       if (!vc4_hdmi_is_full_range_rgb(vc4_hdmi, mode))
 110 +               vc5_hdmi_set_csc_coeffs(vc4_hdmi, vc5_hdmi_csc_full_rgb_to_limited_rgb);
 111 +       else
 112 +               vc5_hdmi_set_csc_coeffs(vc4_hdmi, vc5_hdmi_csc_full_rgb_unity);
 113
 114         HDMI_WRITE(HDMI_CSC_CTL, csc_ctl);
 115