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dm: video: Add an EFI framebuffer driver

This adds a DM video driver for U-Boot as the EFI payload. The driver
makes use of all necessary information from the passed EFI GOP info
to create a linear framebuffer device, as if it were initialized by
U-Boot itself.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anatolij Gustschin <agust@denx.de>
tags/2020-06-01
Bin Meng 2 years ago
parent
commit
4a08c74697
3 changed files with 156 additions and 0 deletions
  1. +9
    -0
      drivers/video/Kconfig
  2. +1
    -0
      drivers/video/Makefile
  3. +146
    -0
      drivers/video/efi.c

+ 9
- 0
drivers/video/Kconfig View File

@@ -156,6 +156,15 @@ config VIDEO_COREBOOT
coreboot already. This can in principle be used with any platform
that coreboot supports.

config VIDEO_EFI
bool "Enable EFI framebuffer driver support"
depends on EFI_STUB
help
Turn on this option to enable a framebuffeer driver when U-Boot is
loaded as a payload (see README.u-boot_on_efi) by an EFI BIOS where
the graphics device is configured by the EFI BIOS already. This can
in principle be used with any platform that has an EFI BIOS.

config VIDEO_VESA
bool "Enable VESA video driver support"
default n


+ 1
- 0
drivers/video/Makefile View File

@@ -32,6 +32,7 @@ obj-$(CONFIG_LD9040) += ld9040.o
obj-$(CONFIG_VIDEO_BCM2835) += bcm2835.o
obj-$(CONFIG_VIDEO_COREBOOT) += coreboot.o
obj-$(CONFIG_VIDEO_DA8XX) += da8xx-fb.o videomodes.o
obj-$(CONFIG_VIDEO_EFI) += efi.o
obj-$(CONFIG_VIDEO_LCD_ANX9804) += anx9804.o
obj-$(CONFIG_VIDEO_LCD_HITACHI_TX18D42VM) += hitachi_tx18d42vm_lcd.o
obj-$(CONFIG_VIDEO_LCD_SSD2828) += ssd2828.o


+ 146
- 0
drivers/video/efi.c View File

@@ -0,0 +1,146 @@
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
*
* EFI framebuffer driver based on GOP
*/

#include <common.h>
#include <dm.h>
#include <efi_api.h>
#include <vbe.h>
#include <video.h>

struct pixel {
u8 pos;
u8 size;
};

static const struct efi_framebuffer {
struct pixel red;
struct pixel green;
struct pixel blue;
struct pixel rsvd;
} efi_framebuffer_format_map[] = {
[EFI_GOT_RGBA8] = { {0, 8}, {8, 8}, {16, 8}, {24, 8} },
[EFI_GOT_BGRA8] = { {16, 8}, {8, 8}, {0, 8}, {24, 8} },
};

static void efi_find_pixel_bits(u32 mask, u8 *pos, u8 *size)
{
u8 first, len;

first = 0;
len = 0;

if (mask) {
while (!(mask & 0x1)) {
mask = mask >> 1;
first++;
}

while (mask & 0x1) {
mask = mask >> 1;
len++;
}
}

*pos = first;
*size = len;
}

static int save_vesa_mode(struct vesa_mode_info *vesa)
{
struct efi_entry_gopmode *mode;
const struct efi_framebuffer *fbinfo;
int size;
int ret;

ret = efi_info_get(EFIET_GOP_MODE, (void **)&mode, &size);
if (ret == -ENOENT) {
debug("efi graphics output protocol mode not found\n");
return -ENXIO;
}

vesa->phys_base_ptr = mode->fb_base;
vesa->x_resolution = mode->info->width;
vesa->y_resolution = mode->info->height;

if (mode->info->pixel_format < EFI_GOT_BITMASK) {
fbinfo = &efi_framebuffer_format_map[mode->info->pixel_format];
vesa->red_mask_size = fbinfo->red.size;
vesa->red_mask_pos = fbinfo->red.pos;
vesa->green_mask_size = fbinfo->green.size;
vesa->green_mask_pos = fbinfo->green.pos;
vesa->blue_mask_size = fbinfo->blue.size;
vesa->blue_mask_pos = fbinfo->blue.pos;
vesa->reserved_mask_size = fbinfo->rsvd.size;
vesa->reserved_mask_pos = fbinfo->rsvd.pos;

vesa->bits_per_pixel = 32;
vesa->bytes_per_scanline = mode->info->pixels_per_scanline * 4;
} else if (mode->info->pixel_format == EFI_GOT_BITMASK) {
efi_find_pixel_bits(mode->info->pixel_bitmask[0],
&vesa->red_mask_pos,
&vesa->red_mask_size);
efi_find_pixel_bits(mode->info->pixel_bitmask[1],
&vesa->green_mask_pos,
&vesa->green_mask_size);
efi_find_pixel_bits(mode->info->pixel_bitmask[2],
&vesa->blue_mask_pos,
&vesa->blue_mask_size);
efi_find_pixel_bits(mode->info->pixel_bitmask[3],
&vesa->reserved_mask_pos,
&vesa->reserved_mask_size);
vesa->bits_per_pixel = vesa->red_mask_size +
vesa->green_mask_size +
vesa->blue_mask_size +
vesa->reserved_mask_size;
vesa->bytes_per_scanline = (mode->info->pixels_per_scanline *
vesa->bits_per_pixel) / 8;
} else {
debug("efi set unknown framebuffer format: %d\n",
mode->info->pixel_format);
return -EINVAL;
}

return 0;
}

static int efi_video_probe(struct udevice *dev)
{
struct video_uc_platdata *plat = dev_get_uclass_platdata(dev);
struct video_priv *uc_priv = dev_get_uclass_priv(dev);
struct vesa_mode_info *vesa = &mode_info.vesa;
int ret;

/* Initialize vesa_mode_info structure */
ret = save_vesa_mode(vesa);
if (ret)
goto err;

ret = vbe_setup_video_priv(vesa, uc_priv, plat);
if (ret)
goto err;

printf("Video: %dx%dx%d\n", uc_priv->xsize, uc_priv->ysize,
vesa->bits_per_pixel);

return 0;

err:
printf("No video mode configured in EFI!\n");
return ret;
}

static const struct udevice_id efi_video_ids[] = {
{ .compatible = "efi-fb" },
{ }
};

U_BOOT_DRIVER(efi_video) = {
.name = "efi_video",
.id = UCLASS_VIDEO,
.of_match = efi_video_ids,
.probe = efi_video_probe,
};

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