e920a0be64708a26917926a76c29ffa90e973352
[oweals/openwrt.git] / target / linux / bcm27xx / patches-5.4 / 950-0564-drm-vc4-crtc-Add-FIFO-depth-to-vc4_crtc_data.patch
1 From a294de7c4782f91fe724e4e5b05fd99798d50760 Mon Sep 17 00:00:00 2001
2 From: Maxime Ripard <maxime@cerno.tech>
3 Date: Mon, 13 Jan 2020 13:39:20 +0100
4 Subject: [PATCH] drm/vc4: crtc: Add FIFO depth to vc4_crtc_data
5
6 Not all pixelvalve FIFOs in vc5 have the same depth, so we need to add that
7 to our vc4_crtc_data structure to be able to compute the fill level
8 properly later on.
9
10 Signed-off-by: Maxime Ripard <maxime@cerno.tech>
11 ---
12  drivers/gpu/drm/vc4/vc4_crtc.c | 20 ++++++++++++++++----
13  drivers/gpu/drm/vc4/vc4_drv.h  |  3 +++
14  2 files changed, 19 insertions(+), 4 deletions(-)
15
16 --- a/drivers/gpu/drm/vc4/vc4_crtc.c
17 +++ b/drivers/gpu/drm/vc4/vc4_crtc.c
18 @@ -250,11 +250,20 @@ vc4_crtc_update_gamma_lut(struct drm_crt
19         vc4_crtc_lut_load(crtc);
20  }
21  
22 -
23 -static u32 vc4_get_fifo_full_level(u32 format)
24 +static u32 vc4_get_fifo_full_level(struct vc4_crtc *vc4_crtc, u32 format)
25  {
26 -       static const u32 fifo_len_bytes = 64;
27 +       u32 fifo_len_bytes = vc4_crtc->data->fifo_depth;
28  
29 +       /*
30 +        * Pixels are pulled from the HVS if the number of bytes is
31 +        * lower than the FIFO full level.
32 +        *
33 +        * The latency of the pixel fetch mechanism is 6 pixels, so we
34 +        * need to convert those 6 pixels in bytes, depending on the
35 +        * format, and then substract that from the length of the FIFO
36 +        * to make sure we never end up in a situation where the FIFO
37 +        * is full.
38 +        */
39         switch (format) {
40         case PV_CONTROL_FORMAT_DSIV_16:
41         case PV_CONTROL_FORMAT_DSIC_16:
42 @@ -369,7 +378,7 @@ static void vc4_crtc_config_pv(struct dr
43  
44         CRTC_WRITE(PV_CONTROL,
45                    VC4_SET_FIELD(format, PV_CONTROL_FORMAT) |
46 -                  VC4_SET_FIELD(vc4_get_fifo_full_level(format),
47 +                  VC4_SET_FIELD(vc4_get_fifo_full_level(vc4_crtc, format),
48                                  PV_CONTROL_FIFO_LEVEL) |
49                    VC4_SET_FIELD(pixel_rep - 1, PV_CONTROL_PIXEL_REP) |
50                    PV_CONTROL_CLR_AT_START |
51 @@ -1067,6 +1076,7 @@ static const struct vc4_crtc_data bcm283
52         .hvs_available_channels = BIT(0),
53         .hvs_output = 0,
54         .debugfs_name = "crtc0_regs",
55 +       .fifo_depth = 64,
56         .pixels_per_clock = 1,
57         .encoder_types = {
58                 [PV_CONTROL_CLK_SELECT_DSI] = VC4_ENCODER_TYPE_DSI0,
59 @@ -1078,6 +1088,7 @@ static const struct vc4_crtc_data bcm283
60         .hvs_available_channels = BIT(2),
61         .hvs_output = 2,
62         .debugfs_name = "crtc1_regs",
63 +       .fifo_depth = 64,
64         .pixels_per_clock = 1,
65         .encoder_types = {
66                 [PV_CONTROL_CLK_SELECT_DSI] = VC4_ENCODER_TYPE_DSI1,
67 @@ -1089,6 +1100,7 @@ static const struct vc4_crtc_data bcm283
68         .hvs_available_channels = BIT(1),
69         .hvs_output = 1,
70         .debugfs_name = "crtc2_regs",
71 +       .fifo_depth = 64,
72         .pixels_per_clock = 1,
73         .encoder_types = {
74                 [PV_CONTROL_CLK_SELECT_DPI_SMI_HDMI] = VC4_ENCODER_TYPE_HDMI,
75 --- a/drivers/gpu/drm/vc4/vc4_drv.h
76 +++ b/drivers/gpu/drm/vc4/vc4_drv.h
77 @@ -452,6 +452,9 @@ to_vc4_encoder(struct drm_encoder *encod
78  }
79  
80  struct vc4_crtc_data {
81 +       /* Depth of the PixelValve FIFO in bytes */
82 +       unsigned int fifo_depth;
83 +
84         /* Which channels of the HVS can the output source from */
85         unsigned int hvs_available_channels;
86