diff options
author | Arvind Sankar <nivedita@alum.mit.edu> | 2020-03-28 12:06:01 -0400 |
---|---|---|
committer | Ard Biesheuvel <ardb@kernel.org> | 2020-04-23 20:15:06 +0200 |
commit | 45d97a749e9fec6d5324b19561ce5fbfa937d60b (patch) | |
tree | 3bf12305975b235657491767a0cd95ea7148e6ec /drivers/firmware/efi | |
parent | 9a1663bc4d9856f6810786fec597dab5440a9d8d (diff) |
efi/gop: Allow automatically choosing the best mode
Add the ability to automatically pick the highest resolution video mode
(defined as the product of vertical and horizontal resolution) by using
a command-line argument of the form
video=efifb:auto
If there are multiple modes with the highest resolution, pick one with
the highest color depth.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200328160601.378299-2-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 848cb605a9c4..fa05a0b0adfd 100644 --- a/drivers/firmware/efi/libstub/gop.c +++ b/drivers/firmware/efi/libstub/gop.c @@ -18,7 +18,8 @@ enum efi_cmdline_option { EFI_CMDLINE_NONE, EFI_CMDLINE_MODE_NUM, - EFI_CMDLINE_RES + EFI_CMDLINE_RES, + EFI_CMDLINE_AUTO }; static struct { @@ -86,6 +87,19 @@ static bool parse_res(char *option, char **next) return true; } +static bool parse_auto(char *option, char **next) +{ + if (!strstarts(option, "auto")) + return false; + option += strlen("auto"); + if (*option && *option++ != ',') + return false; + cmdline.option = EFI_CMDLINE_AUTO; + + *next = option; + return true; +} + void efi_parse_option_graphics(char *option) { while (*option) { @@ -93,6 +107,8 @@ void efi_parse_option_graphics(char *option) continue; if (parse_res(option, &option)) continue; + if (parse_auto(option, &option)) + continue; while (*option && *option++ != ',') ; @@ -211,6 +227,69 @@ static u32 choose_mode_res(efi_graphics_output_protocol_t *gop) return cur_mode; } +static u32 choose_mode_auto(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, best_mode, area; + u8 depth; + int pf; + efi_pixel_bitmask_t pi; + u32 m, w, h, a; + u8 d; + + mode = efi_table_attr(gop, mode); + + cur_mode = efi_table_attr(mode, mode); + max_mode = efi_table_attr(mode, max_mode); + + info = efi_table_attr(mode, info); + + pf = info->pixel_format; + pi = info->pixel_information; + w = info->horizontal_resolution; + h = info->vertical_resolution; + + best_mode = cur_mode; + area = w * h; + depth = pixel_bpp(pf, pi); + + 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; + pi = info->pixel_information; + w = info->horizontal_resolution; + h = info->vertical_resolution; + + efi_bs_call(free_pool, info); + + if (pf == PIXEL_BLT_ONLY || pf >= PIXEL_FORMAT_MAX) + continue; + a = w * h; + if (a < area) + continue; + d = pixel_bpp(pf, pi); + if (a > area || d > depth) { + best_mode = m; + area = a; + depth = d; + } + } + + return best_mode; +} + static void set_mode(efi_graphics_output_protocol_t *gop) { efi_graphics_output_protocol_mode_t *mode; @@ -223,6 +302,9 @@ static void set_mode(efi_graphics_output_protocol_t *gop) case EFI_CMDLINE_RES: new_mode = choose_mode_res(gop); break; + case EFI_CMDLINE_AUTO: + new_mode = choose_mode_auto(gop); + break; default: return; } |