diff options
author | Arvind Sankar <nivedita@alum.mit.edu> | 2020-03-19 22:00:26 -0400 |
---|---|---|
committer | Ard Biesheuvel <ardb@kernel.org> | 2020-04-23 20:15:06 +0200 |
commit | d9ff0323d074c6c06467118c7a43d5748f147369 (patch) | |
tree | bd3f9a7875996c255c9e88705259b90f0883e756 /drivers/firmware/efi | |
parent | fffb68047e563fb74f782c726e9bdf1fa117d93d (diff) |
efi/gop: Allow specifying mode by <xres>x<yres>
Add the ability to choose a video mode using a command-line argument of
the form
video=efifb:<xres>x<yres>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-13-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Diffstat (limited to 'drivers/firmware/efi')
-rw-r--r-- | drivers/firmware/efi/libstub/gop.c | 84 |
1 files changed, 83 insertions, 1 deletions
diff --git a/drivers/firmware/efi/libstub/gop.c b/drivers/firmware/efi/libstub/gop.c index a32b784b4577..cc84e6a82f54 100644 --- a/drivers/firmware/efi/libstub/gop.c +++ b/drivers/firmware/efi/libstub/gop.c @@ -6,6 +6,7 @@ * ----------------------------------------------------------------------- */ #include <linux/bitops.h> +#include <linux/ctype.h> #include <linux/efi.h> #include <linux/screen_info.h> #include <linux/string.h> @@ -17,11 +18,17 @@ enum efi_cmdline_option { EFI_CMDLINE_NONE, EFI_CMDLINE_MODE_NUM, + EFI_CMDLINE_RES }; static struct { enum efi_cmdline_option option; - u32 mode; + union { + u32 mode; + struct { + u32 width, height; + } res; + }; } cmdline __efistub_global = { .option = EFI_CMDLINE_NONE }; static bool parse_modenum(char *option, char **next) @@ -41,11 +48,33 @@ static bool parse_modenum(char *option, char **next) return true; } +static bool parse_res(char *option, char **next) +{ + u32 w, h; + + if (!isdigit(*option)) + return false; + w = simple_strtoull(option, &option, 10); + if (*option++ != 'x' || !isdigit(*option)) + return false; + h = simple_strtoull(option, &option, 10); + if (*option && *option++ != ',') + return false; + cmdline.option = EFI_CMDLINE_RES; + cmdline.res.width = w; + cmdline.res.height = h; + + *next = option; + return true; +} + void efi_parse_option_graphics(char *option) { while (*option) { if (parse_modenum(option, &option)) continue; + if (parse_res(option, &option)) + continue; while (*option && *option++ != ',') ; @@ -94,6 +123,56 @@ static u32 choose_mode_modenum(efi_graphics_output_protocol_t *gop) return cmdline.mode; } +static u32 choose_mode_res(efi_graphics_output_protocol_t *gop) +{ + efi_status_t status; + + efi_graphics_output_protocol_mode_t *mode; + efi_graphics_output_mode_info_t *info; + unsigned long info_size; + + u32 max_mode, cur_mode; + int pf; + u32 m, w, h; + + mode = efi_table_attr(gop, mode); + + cur_mode = efi_table_attr(mode, mode); + info = efi_table_attr(mode, info); + w = info->horizontal_resolution; + h = info->vertical_resolution; + + if (w == cmdline.res.width && h == cmdline.res.height) + return cur_mode; + + max_mode = efi_table_attr(mode, max_mode); + + for (m = 0; m < max_mode; m++) { + if (m == cur_mode) + continue; + + status = efi_call_proto(gop, query_mode, m, + &info_size, &info); + if (status != EFI_SUCCESS) + continue; + + pf = info->pixel_format; + w = info->horizontal_resolution; + h = info->vertical_resolution; + + efi_bs_call(free_pool, info); + + if (pf == PIXEL_BLT_ONLY || pf >= PIXEL_FORMAT_MAX) + continue; + if (w == cmdline.res.width && h == cmdline.res.height) + return m; + } + + efi_printk("Couldn't find requested mode\n"); + + return cur_mode; +} + static void set_mode(efi_graphics_output_protocol_t *gop) { efi_graphics_output_protocol_mode_t *mode; @@ -103,6 +182,9 @@ static void set_mode(efi_graphics_output_protocol_t *gop) case EFI_CMDLINE_MODE_NUM: new_mode = choose_mode_modenum(gop); break; + case EFI_CMDLINE_RES: + new_mode = choose_mode_res(gop); + break; default: return; } |