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