// SPDX-License-Identifier: GPL-2.0
/*
* Framebuffer driver for EFI/UEFI based system
*
* (c) 2006 Edgar Hucek <[email protected]>
* Original efi driver written by Gerd Knorr <[email protected]>
*
*/
#include <linux/aperture.h>
#include <linux/kernel.h>
#include <linux/efi.h>
#include <linux/efi-bgrt.h>
#include <linux/errno.h>
#include <linux/fb.h>
#include <linux/platform_device.h>
#include <linux/printk.h>
#include <linux/screen_info.h>
#include <video/vga.h>
#include <asm/efi.h>
#include <drm/drm_utils.h> /* For drm_get_panel_orientation_quirk */
#include <drm/drm_connector.h> /* For DRM_MODE_PANEL_ORIENTATION_* */
struct bmp_file_header {
u16 id;
u32 file_size;
u32 reserved;
u32 bitmap_offset;
} __packed;
struct bmp_dib_header {
u32 dib_header_size;
s32 width;
s32 height;
u16 planes;
u16 bpp;
u32 compression;
u32 bitmap_size;
u32 horz_resolution;
u32 vert_resolution;
u32 colors_used;
u32 colors_important;
} __packed;
static bool use_bgrt = true;
static bool request_mem_succeeded = false;
static u64 mem_flags = EFI_MEMORY_WC | EFI_MEMORY_UC;
struct efifb_par {
u32 pseudo_palette[16];
resource_size_t base;
resource_size_t size;
};
static struct fb_var_screeninfo efifb_defined = {
.activate = FB_ACTIVATE_NOW,
.height = -1,
.width = -1,
.right_margin = 32,
.upper_margin = 16,
.lower_margin = 4,
.vsync_len = 4,
.vmode = FB_VMODE_NONINTERLACED,
};
static struct fb_fix_screeninfo efifb_fix = {
.id = "EFI VGA",
.type = FB_TYPE_PACKED_PIXELS,
.accel = FB_ACCEL_NONE,
.visual = FB_VISUAL_TRUECOLOR,
};
static int efifb_setcolreg(unsigned regno, unsigned red, unsigned green,
unsigned blue, unsigned transp,
struct fb_info *info)
{
/*
* Set a single color register. The values supplied are
* already rounded down to the hardware's capabilities
* (according to the entries in the `var' structure). Return
* != 0 for invalid regno.
*/
if (regno >= info->cmap.len)
return 1;
if (regno < 16) {
red >>= 16 - info->var.red.length;
green >>= 16 - info->var.green.length;
blue >>= 16 - info->var.blue.length;
((u32 *)(info->pseudo_palette))[regno] =
(red << info->var.red.offset) |
(green << info->var.green.offset) |
(blue << info->var.blue.offset);
}
return 0;
}
/*
* If fbcon deffered console takeover is configured, the intent is for the
* framebuffer to show the boot graphics (e.g. vendor logo) until there is some
* (error) message to display. But the boot graphics may have been destroyed by
* e.g. option ROM output, detect this and restore the boot graphics.
*/
#if defined CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER && \
defined CONFIG_ACPI_BGRT
static void efifb_copy_bmp(u8 *src, u32 *dst, int width, const struct screen_info *si)
{
u8 r, g, b;
while (width--) {
b = *src++;
g = *src++;
r = *src++;
*dst++ = (r << si->red_pos) |
(g << si->green_pos) |
(b << si->blue_pos);
}
}
#ifdef CONFIG_X86
/*
* On x86 some firmwares use a low non native resolution for the display when
* they have shown some text messages. While keeping the bgrt filled with info
* for the native resolution. If the bgrt image intended for the native
* resolution still fits, it will be displayed very close to the right edge of
* the display looking quite bad. This function checks for this.
*/
static bool efifb_bgrt_sanity_check(const struct screen_info *si, u32 bmp_width)
{
/*
* All x86 firmwares horizontally center the image (the yoffset
* calculations differ between boards, but xoffset is predictable).
*/
u32 expected_xoffset = (si->lfb_width - bmp_width) / 2;
return bgrt_tab.image_offset_x == expected_xoffset;
}
#else
static bool efifb_bgrt_sanity_check(const struct screen_info *si, u32 bmp_width)
{
return true;
}
#endif
static void efifb_show_boot_graphics(struct fb_info *info, const struct screen_info *si)
{
u32 bmp_width, bmp_height, bmp_pitch, dst_x, y, src_y;
struct bmp_file_header *file_header;
struct bmp_dib_header *dib_header;
void *bgrt_image = NULL;
u8 *dst = info->screen_base;
if (!use_bgrt)
return;
if (!bgrt_tab.image_address) {
pr_info("efifb: No BGRT, not showing boot graphics\n");
return;
}
if (bgrt_tab.status & 0x06) {
pr_info("efifb: BGRT rotation bits set, not showing boot graphics\n");
return;
}
/* Avoid flashing the logo if we're going to print std probe messages */
if (console_loglevel > CONSOLE_LOGLEVEL_QUIET)
return;
/* bgrt_tab.status is unreliable, so we don't check it */
if (si->lfb_depth != 32) {
pr_info("efifb: not 32 bits, not showing boot graphics\n");
return;
}
bgrt_image = memremap(bgrt_tab.image_address, bgrt_image_size,
MEMREMAP_WB);
if (!bgrt_image) {
pr_warn("efifb: Ignoring BGRT: failed to map image memory\n");
return;
}
if (bgrt_image_size < (sizeof(*file_header) + sizeof(*dib_header)))
goto error;
file_header = bgrt_image;
if (file_header->id != 0x4d42 || file_header->reserved != 0)
goto error;
dib_header = bgrt_image + sizeof(*file_header);
if (dib_header->dib_header_size != 40 || dib_header->width < 0 ||
dib_header->planes != 1 || dib_header->bpp != 24 ||
dib_header->compression != 0)
goto error;
bmp_width = dib_header->width;
bmp_height = abs(dib_header->height);
bmp_pitch = round_up(3 * bmp_width, 4);
if ((file_header->bitmap_offset + bmp_pitch * bmp_height) >
bgrt_image_size)
goto error;
if ((bgrt_tab.image_offset_x + bmp_width) > si->lfb_width ||
(bgrt_tab.image_offset_y + bmp_height) > si->lfb_height)
goto error;
if (!efifb_bgrt_sanity_check(si, bmp_width))
goto error;
pr_info("efifb: showing boot graphics\n");
for (y = 0; y < si->lfb_height; y++, dst += si->lfb_linelength) {
/* Only background? */
if (y < bgrt_tab.image_offset_y ||
y >= (bgrt_tab.image_offset_y + bmp_height)) {
memset(dst, 0, 4 * si->lfb_width);
continue;
}
src_y = y - bgrt_tab.image_offset_y;
/* Positive header height means upside down row order */
if (dib_header->height > 0)
src_y = (bmp_height - 1) - src_y;
memset(dst, 0, bgrt_tab.image_offset_x * 4);
dst_x = bgrt_tab.image_offset_x;
efifb_copy_bmp(bgrt_image + file_header->bitmap_offset +
src_y * bmp_pitch,
(u32 *)dst + dst_x, bmp_width, si);
dst_x += bmp_width;
memset((u32 *)dst + dst_x, 0, (si->lfb_width - dst_x) * 4);
}
memunmap(bgrt_image);
return;
error:
memunmap(bgrt_image);
pr_warn("efifb: Ignoring BGRT: unexpected or invalid BMP data\n");
}
#else
static inline void efifb_show_boot_graphics(struct fb_info *info, const struct screen_info *si)
{ }
#endif
/*
* fb_ops.fb_destroy is called by the last put_fb_info() call at the end
* of unregister_framebuffer() or fb_release(). Do any cleanup here.
*/
static void efifb_destroy(struct fb_info *info)
{
struct efifb_par *par = info->par;
if (info->screen_base) {
if (mem_flags & (EFI_MEMORY_UC | EFI_MEMORY_WC))
iounmap(info->screen_base);
else
memunmap(info->screen_base);
}
if (request_mem_succeeded)
release_mem_region(par->base, par->size);
fb_dealloc_cmap(&info->cmap);
framebuffer_release(info);
}
static const struct fb_ops efifb_ops = {
.owner = THIS_MODULE,
FB_DEFAULT_IOMEM_OPS,
.fb_destroy = efifb_destroy,
.fb_setcolreg = efifb_setcolreg,
};
static int efifb_setup(struct screen_info *si, char *options)
{
char *this_opt;
if (options && *options) {
while ((this_opt = strsep(&options, ",")) != NULL) {
if (!*this_opt) continue;
efifb_setup_from_dmi(si, this_opt);
if (!strncmp(this_opt, "base:", 5))
si->lfb_base = simple_strtoul(this_opt+5, NULL, 0);
else if (!strncmp(this_opt, "stride:", 7))
si->lfb_linelength = simple_strtoul(this_opt+7, NULL, 0) * 4;
else if (!strncmp(this_opt, "height:", 7))
si->lfb_height = simple_strtoul(this_opt+7, NULL, 0);
else if (!strncmp(this_opt, "width:", 6))
si->lfb_width = simple_strtoul(this_opt+6, NULL, 0);
else if (!strcmp(this_opt, "nowc"))
mem_flags &= ~EFI_MEMORY_WC;
else if (!strcmp(this_opt, "nobgrt"))
use_bgrt = false;
}
}
return 0;
}
static inline bool fb_base_is_valid(struct screen_info *si)
{
if (si->lfb_base)
return true;
if (!(si->capabilities & VIDEO_CAPABILITY_64BIT_BASE))
return false;
if (si->ext_lfb_base)
return true;
return false;
}
#define efifb_attr_decl(name, fmt) \
static ssize_t name##_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
{ \
struct screen_info *si = dev_get_drvdata(dev); \
if (!si) \
return -ENODEV; \
return sprintf(buf, fmt "\n", (si->lfb_##name)); \
} \
static DEVICE_ATTR_RO(name)
efifb_attr_decl(base, "0x%x");
efifb_attr_decl(linelength, "%u");
efifb_attr_decl(height, "%u");
efifb_attr_decl(width, "%u");
efifb_attr_decl(depth, "%u");
static struct attribute *efifb_attrs[] = {
&dev_attr_base.attr,
&dev_attr_linelength.attr,
&dev_attr_width.attr,
&dev_attr_height.attr,
&dev_attr_depth.attr,
NULL
};
ATTRIBUTE_GROUPS(efifb);
static int efifb_probe(struct platform_device *dev)
{
struct screen_info *si;
struct fb_info *info;
struct efifb_par *par;
int err, orientation;
unsigned int size_vmode;
unsigned int size_remap;
unsigned int size_total;
char *option = NULL;
efi_memory_desc_t md;
/*
* If we fail probing the device, the kernel might try a different
* driver. We get a copy of the attached screen_info, so that we can
* modify its values without affecting later drivers.
*/
si = dev_get_platdata(&dev->dev);
if (!si)
return -ENODEV;
si = devm_kmemdup(&dev->dev, si, sizeof(*si), GFP_KERNEL);
if (!si)
return -ENOMEM;
dev_set_drvdata(&dev->dev, si);
if (si->orig_video_isVGA != VIDEO_TYPE_EFI)
return -ENODEV;
if (fb_get_options("efifb", &option))
return -ENODEV;
efifb_setup(si, option);
/* We don't get linelength from UGA Draw Protocol, only from
* EFI Graphics Protocol. So if it's not in DMI, and it's not
* passed in from the user, we really can't use the framebuffer.
*/
if (!si->lfb_linelength)
return -ENODEV;
if (!si->lfb_depth)
si->lfb_depth = 32;
if (!si->pages)
si->pages = 1;
if (!fb_base_is_valid(si)) {
printk(KERN_DEBUG "efifb: invalid framebuffer address\n");
return -ENODEV;
}
printk(KERN_INFO "efifb: probing for efifb\n");
/* just assume they're all unset if any are */
if (!si->blue_size) {
si->blue_size = 8;
si->blue_pos = 0;
si->green_size = 8;
si->green_pos = 8;
si->red_size = 8;
si->red_pos = 16;
si->rsvd_size = 8;
si->rsvd_pos = 24;
}
efifb_fix.smem_start = __screen_info_lfb_base(si);
efifb_defined.bits_per_pixel = si->lfb_depth;
efifb_defined.xres = si->lfb_width;
efifb_defined.yres = si->lfb_height;
efifb_fix.line_length = si->lfb_linelength;
/* size_vmode -- that is the amount of memory needed for the
* used video mode, i.e. the minimum amount of
* memory we need. */
size_vmode = efifb_defined.yres * efifb_fix.line_length;
/* size_total -- all video memory we have. Used for
* entries, ressource allocation and bounds
* checking. */
size_total = si->lfb_size;
if (size_total < size_vmode)
size_total = size_vmode;
/* size_remap -- the amount of video memory we are going to
* use for efifb. With modern cards it is no
* option to simply use size_total as that
* wastes plenty of kernel address space. */
size_remap = size_vmode * 2;
if (size_remap > size_total)
size_remap = size_total;
if (size_remap % PAGE_SIZE)
size_remap += PAGE_SIZE - (size_remap % PAGE_SIZE);
efifb_fix.smem_len = size_remap;
if (request_mem_region(efifb_fix.smem_start, size_remap, "efifb")) {
request_mem_succeeded = true;
} else {
/* We cannot make this fatal. Sometimes this comes from magic
spaces our resource handlers simply don't know about */
pr_warn("efifb: cannot reserve video memory at 0x%lx\n",
efifb_fix.smem_start);
}
info = framebuffer_alloc(sizeof(*par), &dev->dev);
if (!info) {
err = -ENOMEM;
goto err_release_mem;
}
par = info->par;
info->pseudo_palette = par->pseudo_palette;
par->base = efifb_fix.smem_start;
par->size = size_remap;
if (efi_enabled(EFI_MEMMAP) &&
!efi_mem_desc_lookup(efifb_fix.smem_start, &md)) {
if ((efifb_fix.smem_start + efifb_fix.smem_len) >
(md.phys_addr + (md.num_pages << EFI_PAGE_SHIFT))) {
pr_err("efifb: video memory @ 0x%lx spans multiple EFI memory regions\n",
efifb_fix.smem_start);
err = -EIO;
goto err_release_fb;
}
/*
* If the UEFI memory map covers the efifb region, we may only
* remap it using the attributes the memory map prescribes.
*/
md.attribute &= EFI_MEMORY_UC | EFI_MEMORY_WC |
EFI_MEMORY_WT | EFI_MEMORY_WB;
if (md.attribute) {
mem_flags |= EFI_MEMORY_WT | EFI_MEMORY_WB;
mem_flags &= md.attribute;
}
}
if (mem_flags & EFI_MEMORY_WC)
info->screen_base = ioremap_wc(efifb_fix.smem_start,
efifb_fix.smem_len);
else if (mem_flags & EFI_MEMORY_UC)
info->screen_base = ioremap(efifb_fix.smem_start,
efifb_fix.smem_len);
else if (mem_flags & EFI_MEMORY_WT)
info->screen_base = memremap(efifb_fix.smem_start,
efifb_fix.smem_len, MEMREMAP_WT);
else if (mem_flags & EFI_MEMORY_WB)
info->screen_base = memremap(efifb_fix.smem_start,
efifb_fix.smem_len, MEMREMAP_WB);
if (!info->screen_base) {
pr_err("efifb: abort, cannot remap video memory 0x%x @ 0x%lx\n",
efifb_fix.smem_len, efifb_fix.smem_start);
err = -EIO;
goto err_release_fb;
}
efifb_show_boot_graphics(info, si);
pr_info("efifb: framebuffer at 0x%lx, using %dk, total %dk\n",
efifb_fix.smem_start, size_remap/1024, size_total/1024);
pr_info("efifb: mode is %dx%dx%d, linelength=%d, pages=%d\n",
efifb_defined.xres, efifb_defined.yres,
efifb_defined.bits_per_pixel, efifb_fix.line_length,
si->pages);
efifb_defined.xres_virtual = efifb_defined.xres;
efifb_defined.yres_virtual = efifb_fix.smem_len /
efifb_fix.line_length;
pr_info("efifb: scrolling: redraw\n");
efifb_defined.yres_virtual = efifb_defined.yres;
/* some dummy values for timing to make fbset happy */
efifb_defined.pixclock = 10000000 / efifb_defined.xres *
1000 / efifb_defined.yres;
efifb_defined.left_margin = (efifb_defined.xres / 8) & 0xf8;
efifb_defined.hsync_len = (efifb_defined.xres / 8) & 0xf8;
efifb_defined.red.offset = si->red_pos;
efifb_defined.red.length = si->red_size;
efifb_defined.green.offset = si->green_pos;
efifb_defined.green.length = si->green_size;
efifb_defined.blue.offset = si->blue_pos;
efifb_defined.blue.length = si->blue_size;
efifb_defined.transp.offset = si->rsvd_pos;
efifb_defined.transp.length = si->rsvd_size;
pr_info("efifb: %s: "
"size=%d:%d:%d:%d, shift=%d:%d:%d:%d\n",
"Truecolor",
si->rsvd_size,
si->red_size,
si->green_size,
si->blue_size,
si->rsvd_pos,
si->red_pos,
si->green_pos,
si->blue_pos);
efifb_fix.ypanstep = 0;
efifb_fix.ywrapstep = 0;
info->fbops = &efifb_ops;
info->var = efifb_defined;
info->fix = efifb_fix;
orientation = drm_get_panel_orientation_quirk(efifb_defined.xres,
efifb_defined.yres);
switch (orientation) {
default:
info->fbcon_rotate_hint = FB_ROTATE_UR;
break;
case DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP:
info->fbcon_rotate_hint = FB_ROTATE_UD;
break;
case DRM_MODE_PANEL_ORIENTATION_LEFT_UP:
info->fbcon_rotate_hint = FB_ROTATE_CCW;
break;
case DRM_MODE_PANEL_ORIENTATION_RIGHT_UP:
info->fbcon_rotate_hint = FB_ROTATE_CW;
break;
}
err = fb_alloc_cmap(&info->cmap, 256, 0);
if (err < 0) {
pr_err("efifb: cannot allocate colormap\n");
goto err_unmap;
}
err = devm_aperture_acquire_for_platform_device(dev, par->base, par->size);
if (err) {
pr_err("efifb: cannot acquire aperture\n");
goto err_fb_dealloc_cmap;
}
err = devm_register_framebuffer(&dev->dev, info);
if (err < 0) {
pr_err("efifb: cannot register framebuffer\n");
goto err_fb_dealloc_cmap;
}
fb_info(info, "%s frame buffer device\n", info->fix.id);
return 0;
err_fb_dealloc_cmap:
fb_dealloc_cmap(&info->cmap);
err_unmap:
if (mem_flags & (EFI_MEMORY_UC | EFI_MEMORY_WC))
iounmap(info->screen_base);
else
memunmap(info->screen_base);
err_release_fb:
framebuffer_release(info);
err_release_mem:
if (request_mem_succeeded)
release_mem_region(efifb_fix.smem_start, size_total);
return err;
}
static struct platform_driver efifb_driver = {
.driver = {
.name = "efi-framebuffer",
.dev_groups = efifb_groups,
},
.probe = efifb_probe,
};
builtin_platform_driver(efifb_driver);
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