diff options
| -rw-r--r-- | Documentation/fb/efifb.rst | 20 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/efi-stub-helper.c | 3 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/efistub.h | 2 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/gop.c | 107 |
4 files changed, 129 insertions, 3 deletions
diff --git a/Documentation/fb/efifb.rst b/Documentation/fb/efifb.rst index 04840331a00e..367fbda2f4da 100644 --- a/Documentation/fb/efifb.rst +++ b/Documentation/fb/efifb.rst @@ -2,8 +2,10 @@ What is efifb? ============== -This is a generic EFI platform driver for Intel based Apple computers. -efifb is only for EFI booted Intel Macs. +This is a generic EFI platform driver for systems with UEFI firmware. The +system must be booted via the EFI stub for this to be usable. efifb supports +both firmware with Graphics Output Protocol (GOP) displays as well as older +systems with only Universal Graphics Adapter (UGA) displays. Supported Hardware ================== @@ -12,11 +14,14 @@ Supported Hardware - Macbook - Macbook Pro 15"/17" - MacMini +- ARM/ARM64/X86 systems with UEFI firmware How to use it? ============== -efifb does not have any kind of autodetection of your machine. +For UGA displays, efifb does not have any kind of autodetection of your +machine. + You have to add the following kernel parameters in your elilo.conf:: Macbook : @@ -28,6 +33,9 @@ You have to add the following kernel parameters in your elilo.conf:: Macbook Pro 17", iMac 20" : video=efifb:i20 +For GOP displays, efifb can autodetect the display's resolution and framebuffer +address, so these should work out of the box without any special parameters. + Accepted options: ======= =========================================================== @@ -36,4 +44,10 @@ nowc Don't map the framebuffer write combined. This can be used when large amounts of console data are written. ======= =========================================================== +Options for GOP displays: + +mode=n + The EFI stub will set the mode of the display to mode number n if + possible. + Edgar Hucek <gimli@dark-green.com> diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c index 9f34c7242939..c6092b6038cf 100644 --- a/drivers/firmware/efi/libstub/efi-stub-helper.c +++ b/drivers/firmware/efi/libstub/efi-stub-helper.c @@ -105,6 +105,9 @@ efi_status_t efi_parse_options(char const *cmdline) efi_disable_pci_dma = true; if (parse_option_str(val, "no_disable_early_pci_dma")) efi_disable_pci_dma = false; + } else if (!strcmp(param, "video") && + val && strstarts(val, "efifb:")) { + efi_parse_option_graphics(val + strlen("efifb:")); } } efi_bs_call(free_pool, buf); diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h index 321244ed20a4..9af65be3b278 100644 --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -666,6 +666,8 @@ efi_status_t efi_relocate_kernel(unsigned long *image_addr, efi_status_t efi_parse_options(char const *cmdline); +void efi_parse_option_graphics(char *option); + efi_status_t efi_setup_gop(struct screen_info *si, efi_guid_t *proto, unsigned long size); diff --git a/drivers/firmware/efi/libstub/gop.c b/drivers/firmware/efi/libstub/gop.c index 2d91699e3061..a32b784b4577 100644 --- a/drivers/firmware/efi/libstub/gop.c +++ b/drivers/firmware/efi/libstub/gop.c @@ -8,11 +8,115 @@ #include <linux/bitops.h> #include <linux/efi.h> #include <linux/screen_info.h> +#include <linux/string.h> #include <asm/efi.h> #include <asm/setup.h> #include "efistub.h" +enum efi_cmdline_option { + EFI_CMDLINE_NONE, + EFI_CMDLINE_MODE_NUM, +}; + +static struct { + enum efi_cmdline_option option; + u32 mode; +} cmdline __efistub_global = { .option = EFI_CMDLINE_NONE }; + +static bool parse_modenum(char *option, char **next) +{ + u32 m; + + if (!strstarts(option, "mode=")) + return false; + option += strlen("mode="); + m = simple_strtoull(option, &option, 0); + if (*option && *option++ != ',') + return false; + cmdline.option = EFI_CMDLINE_MODE_NUM; + cmdline.mode = m; + + *next = option; + return true; +} + +void efi_parse_option_graphics(char *option) +{ + while (*option) { + if (parse_modenum(option, &option)) + continue; + + while (*option && *option++ != ',') + ; + } +} + +static u32 choose_mode_modenum(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; + + mode = efi_table_attr(gop, mode); + + cur_mode = efi_table_attr(mode, mode); + if (cmdline.mode == cur_mode) + return cur_mode; + + max_mode = efi_table_attr(mode, max_mode); + if (cmdline.mode >= max_mode) { + efi_printk("Requested mode is invalid\n"); + return cur_mode; + } + + status = efi_call_proto(gop, query_mode, cmdline.mode, + &info_size, &info); + if (status != EFI_SUCCESS) { + efi_printk("Couldn't get mode information\n"); + return cur_mode; + } + + pf = info->pixel_format; + + efi_bs_call(free_pool, info); + + if (pf == PIXEL_BLT_ONLY || pf >= PIXEL_FORMAT_MAX) { + efi_printk("Invalid PixelFormat\n"); + return cur_mode; + } + + return cmdline.mode; +} + +static void set_mode(efi_graphics_output_protocol_t *gop) +{ + efi_graphics_output_protocol_mode_t *mode; + u32 cur_mode, new_mode; + + switch (cmdline.option) { + case EFI_CMDLINE_MODE_NUM: + new_mode = choose_mode_modenum(gop); + break; + default: + return; + } + + mode = efi_table_attr(gop, mode); + cur_mode = efi_table_attr(mode, mode); + + if (new_mode == cur_mode) + return; + + if (efi_call_proto(gop, set_mode, new_mode) != EFI_SUCCESS) + efi_printk("Failed to set requested mode\n"); +} + static void find_bits(u32 mask, u8 *pos, u8 *size) { if (!mask) { @@ -124,6 +228,9 @@ static efi_status_t setup_gop(struct screen_info *si, efi_guid_t *proto, if (!gop) return EFI_NOT_FOUND; + /* Change mode if requested */ + set_mode(gop); + /* EFI framebuffer */ mode = efi_table_attr(gop, mode); info = efi_table_attr(mode, info); |