drivers/video/efi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
   4  *
   5  * EFI framebuffer driver based on GOP
   6  */
   7
   8 #include <common.h>
   9 #include <dm.h>
  10 #include <efi_api.h>
  11 #include <log.h>
  12 #include <vbe.h>
  13 #include <video.h>
  14
  15 struct pixel {
  16         u8 pos;
  17         u8 size;
  18 };
  19
  20 static const struct efi_framebuffer {
  21         struct pixel red;
  22         struct pixel green;
  23         struct pixel blue;
  24         struct pixel rsvd;
  25 } efi_framebuffer_format_map[] = {
  26         [EFI_GOT_RGBA8] = { {0, 8}, {8, 8}, {16, 8}, {24, 8} },
  27         [EFI_GOT_BGRA8] = { {16, 8}, {8, 8}, {0, 8}, {24, 8} },
  28 };
  29
  30 static void efi_find_pixel_bits(u32 mask, u8 *pos, u8 *size)
  31 {
  32         u8 first, len;
  33
  34         first = 0;
  35         len = 0;
  36
  37         if (mask) {
  38                 while (!(mask & 0x1)) {
  39                         mask = mask >> 1;
  40                         first++;
  41                 }
  42
  43                 while (mask & 0x1) {
  44                         mask = mask >> 1;
  45                         len++;
  46                 }
  47         }
  48
  49         *pos = first;
  50         *size = len;
  51 }
  52
  53 static int save_vesa_mode(struct vesa_mode_info *vesa)
  54 {
  55         struct efi_entry_gopmode *mode;
  56         const struct efi_framebuffer *fbinfo;
  57         int size;
  58         int ret;
  59
  60         ret = efi_info_get(EFIET_GOP_MODE, (void **)&mode, &size);
  61         if (ret == -ENOENT) {
  62                 debug("efi graphics output protocol mode not found\n");
  63                 return -ENXIO;
  64         }
  65
  66         vesa->phys_base_ptr = mode->fb_base;
  67         vesa->x_resolution = mode->info->width;
  68         vesa->y_resolution = mode->info->height;
  69
  70         if (mode->info->pixel_format < EFI_GOT_BITMASK) {
  71                 fbinfo = &efi_framebuffer_format_map[mode->info->pixel_format];
  72                 vesa->red_mask_size = fbinfo->red.size;
  73                 vesa->red_mask_pos = fbinfo->red.pos;
  74                 vesa->green_mask_size = fbinfo->green.size;
  75                 vesa->green_mask_pos = fbinfo->green.pos;
  76                 vesa->blue_mask_size = fbinfo->blue.size;
  77                 vesa->blue_mask_pos = fbinfo->blue.pos;
  78                 vesa->reserved_mask_size = fbinfo->rsvd.size;
  79                 vesa->reserved_mask_pos = fbinfo->rsvd.pos;
  80
  81                 vesa->bits_per_pixel = 32;
  82                 vesa->bytes_per_scanline = mode->info->pixels_per_scanline * 4;
  83         } else if (mode->info->pixel_format == EFI_GOT_BITMASK) {
  84                 efi_find_pixel_bits(mode->info->pixel_bitmask[0],
  85                                     &vesa->red_mask_pos,
  86                                     &vesa->red_mask_size);
  87                 efi_find_pixel_bits(mode->info->pixel_bitmask[1],
  88                                     &vesa->green_mask_pos,
  89                                     &vesa->green_mask_size);
  90                 efi_find_pixel_bits(mode->info->pixel_bitmask[2],
  91                                     &vesa->blue_mask_pos,
  92                                     &vesa->blue_mask_size);
  93                 efi_find_pixel_bits(mode->info->pixel_bitmask[3],
  94                                     &vesa->reserved_mask_pos,
  95                                     &vesa->reserved_mask_size);
  96                 vesa->bits_per_pixel = vesa->red_mask_size +
  97                                        vesa->green_mask_size +
  98                                        vesa->blue_mask_size +
  99                                        vesa->reserved_mask_size;
 100                 vesa->bytes_per_scanline = (mode->info->pixels_per_scanline *
 101                                             vesa->bits_per_pixel) / 8;
 102         } else {
 103                 debug("efi set unknown framebuffer format: %d\n",
 104                       mode->info->pixel_format);
 105                 return -EINVAL;
 106         }
 107
 108         return 0;
 109 }
 110
 111 static int efi_video_probe(struct udevice *dev)
 112 {
 113         struct video_uc_plat *plat = dev_get_uclass_plat(dev);
 114         struct video_priv *uc_priv = dev_get_uclass_priv(dev);
 115         struct vesa_mode_info *vesa = &mode_info.vesa;
 116         int ret;
 117
 118         /* Initialize vesa_mode_info structure */
 119         ret = save_vesa_mode(vesa);
 120         if (ret)
 121                 goto err;
 122
 123         ret = vbe_setup_video_priv(vesa, uc_priv, plat);
 124         if (ret)
 125                 goto err;
 126
 127         printf("Video: %dx%dx%d\n", uc_priv->xsize, uc_priv->ysize,
 128                vesa->bits_per_pixel);
 129
 130         return 0;
 131
 132 err:
 133         printf("No video mode configured in EFI!\n");
 134         return ret;
 135 }
 136
 137 static const struct udevice_id efi_video_ids[] = {
 138         { .compatible = "efi-fb" },
 139         { }
 140 };
 141
 142 U_BOOT_DRIVER(efi_video) = {
 143         .name   = "efi_video",
 144         .id     = UCLASS_VIDEO,
 145         .of_match = efi_video_ids,
 146         .probe  = efi_video_probe,
 147 };