target/linux/bcm27xx/patches-5.10/950-0665-drm-vc4-Notify-the-firmware-when-DRM-is-in-charge.patch

   1 From 154a12e5c0d417cae205b8e16431f29c627311e6 Mon Sep 17 00:00:00 2001
   2 From: Maxime Ripard <maxime@cerno.tech>
   3 Date: Wed, 23 Jun 2021 11:54:58 +0200
   4 Subject: [PATCH] drm/vc4: Notify the firmware when DRM is in charge
   5
   6 Once the call to drm_fb_helper_remove_conflicting_framebuffers() has
   7 been made, simplefb has been unregistered and the KMS driver is entirely
   8 in charge of the display.
   9
  10 Thus, we can notify the firmware it can free whatever resource it was
  11 using to maintain simplefb functional.
  12
  13 Signed-off-by: Maxime Ripard <maxime@cerno.tech>
  14 ---
  15  drivers/gpu/drm/vc4/vc4_drv.c | 19 +++++++++++++++++++
  16  1 file changed, 19 insertions(+)
  17
  18 --- a/drivers/gpu/drm/vc4/vc4_drv.c
  19 +++ b/drivers/gpu/drm/vc4/vc4_drv.c
  20 @@ -36,6 +36,8 @@
  21  #include <drm/drm_fb_helper.h>
  22  #include <drm/drm_vblank.h>
  23
  24 +#include <soc/bcm2835/raspberrypi-firmware.h>
  25 +
  26  #include "uapi/drm/vc4_drm.h"
  27
  28  #include "vc4_drv.h"
  29 @@ -305,8 +307,25 @@ static int vc4_drm_bind(struct device *d
  30         if (ret)
  31                 return ret;
  32
  33 +       node = of_parse_phandle(dev->of_node, "raspberrypi,firmware", 0);
  34 +       if (node) {
  35 +               vc4->firmware = rpi_firmware_get(dev->of_node);
  36 +               of_node_put(node);
  37 +
  38 +               if (!vc4->firmware)
  39 +                       return -EPROBE_DEFER;
  40 +       }
  41 +
  42         drm_fb_helper_remove_conflicting_framebuffers(NULL, "vc4drmfb", false);
  43
  44 +       if (vc4->firmware) {
  45 +               ret = rpi_firmware_property(vc4->firmware,
  46 +                                           RPI_FIRMWARE_NOTIFY_DISPLAY_DONE,
  47 +                                           NULL, 0);
  48 +               if (ret)
  49 +                       drm_warn(drm, "Couldn't stop firmware display driver: %d\n", ret);
  50 +       }
  51 +
  52         ret = component_bind_all(dev, drm);
  53         if (ret)
  54                 return ret;