diff options
| -rw-r--r-- | Documentation/fb/fbcon.txt | 7 | ||||
| -rw-r--r-- | drivers/video/console/Kconfig | 11 | ||||
| -rw-r--r-- | drivers/video/console/dummycon.c | 67 | ||||
| -rw-r--r-- | drivers/video/fbdev/core/fbcon.c | 72 | ||||
| -rw-r--r-- | include/linux/console.h | 5 |
5 files changed, 154 insertions, 8 deletions
diff --git a/Documentation/fb/fbcon.txt b/Documentation/fb/fbcon.txt index 79c22d096bbc..d4d642e1ce9c 100644 --- a/Documentation/fb/fbcon.txt +++ b/Documentation/fb/fbcon.txt @@ -155,6 +155,13 @@ C. Boot options used by text. By default, this area will be black. The 'color' value is an integer number that depends on the framebuffer driver being used. +6. fbcon=nodefer + + If the kernel is compiled with deferred fbcon takeover support, normally + the framebuffer contents, left in place by the firmware/bootloader, will + be preserved until there actually is some text is output to the console. + This option causes fbcon to bind immediately to the fbdev device. + C. Attaching, Detaching and Unloading Before going on how to attach, detach and unload the framebuffer console, an diff --git a/drivers/video/console/Kconfig b/drivers/video/console/Kconfig index 4110ba7d7ca9..e91edef98633 100644 --- a/drivers/video/console/Kconfig +++ b/drivers/video/console/Kconfig @@ -150,6 +150,17 @@ config FRAMEBUFFER_CONSOLE_ROTATION such that other users of the framebuffer will remain normally oriented. +config FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER + bool "Framebuffer Console Deferred Takeover" + depends on FRAMEBUFFER_CONSOLE=y && DUMMY_CONSOLE=y + help + If enabled this defers the framebuffer console taking over the + console from the dummy console until the first text is displayed on + the console. This is useful in combination with the "quiet" kernel + commandline option to keep the framebuffer contents initially put up + by the firmware in place, rather then replacing the contents with a + black screen as soon as fbcon loads. + config STI_CONSOLE bool "STI text console" depends on PARISC && HAS_IOMEM diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c index f2eafe2ed980..45ad925ad5f8 100644 --- a/drivers/video/console/dummycon.c +++ b/drivers/video/console/dummycon.c @@ -26,6 +26,65 @@ #define DUMMY_ROWS CONFIG_DUMMY_CONSOLE_ROWS #endif +#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER +/* These are both protected by the console_lock */ +static RAW_NOTIFIER_HEAD(dummycon_output_nh); +static bool dummycon_putc_called; + +void dummycon_register_output_notifier(struct notifier_block *nb) +{ + raw_notifier_chain_register(&dummycon_output_nh, nb); + + if (dummycon_putc_called) + nb->notifier_call(nb, 0, NULL); +} + +void dummycon_unregister_output_notifier(struct notifier_block *nb) +{ + raw_notifier_chain_unregister(&dummycon_output_nh, nb); +} + +static void dummycon_putc(struct vc_data *vc, int c, int ypos, int xpos) +{ + dummycon_putc_called = true; + raw_notifier_call_chain(&dummycon_output_nh, 0, NULL); +} + +static void dummycon_putcs(struct vc_data *vc, const unsigned short *s, + int count, int ypos, int xpos) +{ + int i; + + if (!dummycon_putc_called) { + /* Ignore erases */ + for (i = 0 ; i < count; i++) { + if (s[i] != vc->vc_video_erase_char) + break; + } + if (i == count) + return; + + dummycon_putc_called = true; + } + + raw_notifier_call_chain(&dummycon_output_nh, 0, NULL); +} + +static int dummycon_blank(struct vc_data *vc, int blank, int mode_switch) +{ + /* Redraw, so that we get putc(s) for output done while blanked */ + return 1; +} +#else +static void dummycon_putc(struct vc_data *vc, int c, int ypos, int xpos) { } +static void dummycon_putcs(struct vc_data *vc, const unsigned short *s, + int count, int ypos, int xpos) { } +static int dummycon_blank(struct vc_data *vc, int blank, int mode_switch) +{ + return 0; +} +#endif + static const char *dummycon_startup(void) { return "dummy device"; @@ -44,9 +103,6 @@ static void dummycon_init(struct vc_data *vc, int init) static void dummycon_deinit(struct vc_data *vc) { } static void dummycon_clear(struct vc_data *vc, int sy, int sx, int height, int width) { } -static void dummycon_putc(struct vc_data *vc, int c, int ypos, int xpos) { } -static void dummycon_putcs(struct vc_data *vc, const unsigned short *s, - int count, int ypos, int xpos) { } static void dummycon_cursor(struct vc_data *vc, int mode) { } static bool dummycon_scroll(struct vc_data *vc, unsigned int top, @@ -61,11 +117,6 @@ static int dummycon_switch(struct vc_data *vc) return 0; } -static int dummycon_blank(struct vc_data *vc, int blank, int mode_switch) -{ - return 0; -} - static int dummycon_font_set(struct vc_data *vc, struct console_font *font, unsigned int flags) { diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c index cd8d52a967aa..5fb156bdcf4e 100644 --- a/drivers/video/fbdev/core/fbcon.c +++ b/drivers/video/fbdev/core/fbcon.c @@ -129,6 +129,12 @@ static inline void fbcon_map_override(void) } #endif /* CONFIG_FRAMEBUFFER_CONSOLE_DETECT_PRIMARY */ +#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER +static bool deferred_takeover = true; +#else +#define deferred_takeover false +#endif + /* font data */ static char fontname[40]; @@ -499,6 +505,12 @@ static int __init fb_console_setup(char *this_opt) margin_color = simple_strtoul(options, &options, 0); continue; } +#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER + if (!strcmp(options, "nodefer")) { + deferred_takeover = false; + continue; + } +#endif } return 1; } @@ -3100,6 +3112,9 @@ static int fbcon_fb_unregistered(struct fb_info *info) WARN_CONSOLE_UNLOCKED(); + if (deferred_takeover) + return 0; + idx = info->node; for (i = first_fb_vc; i <= last_fb_vc; i++) { if (con2fb_map[i] == idx) @@ -3140,6 +3155,13 @@ static void fbcon_remap_all(int idx) WARN_CONSOLE_UNLOCKED(); + if (deferred_takeover) { + for (i = first_fb_vc; i <= last_fb_vc; i++) + con2fb_map_boot[i] = idx; + fbcon_map_override(); + return; + } + for (i = first_fb_vc; i <= last_fb_vc; i++) set_con2fb_map(i, idx, 0); @@ -3191,6 +3213,11 @@ static int fbcon_fb_registered(struct fb_info *info) idx = info->node; fbcon_select_primary(info); + if (deferred_takeover) { + pr_info("fbcon: Deferring console take-over\n"); + return 0; + } + if (info_idx == -1) { for (i = first_fb_vc; i <= last_fb_vc; i++) { if (con2fb_map_boot[i] == idx) { @@ -3566,8 +3593,46 @@ static int fbcon_init_device(void) return 0; } +#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER +static struct notifier_block fbcon_output_nb; + +static int fbcon_output_notifier(struct notifier_block *nb, + unsigned long action, void *data) +{ + int i; + + WARN_CONSOLE_UNLOCKED(); + + pr_info("fbcon: Taking over console\n"); + + dummycon_unregister_output_notifier(&fbcon_output_nb); + deferred_takeover = false; + logo_shown = FBCON_LOGO_DONTSHOW; + + for (i = 0; i < FB_MAX; i++) { + if (registered_fb[i]) + fbcon_fb_registered(registered_fb[i]); + } + + return NOTIFY_OK; +} + +static void fbcon_register_output_notifier(void) +{ + fbcon_output_nb.notifier_call = fbcon_output_notifier; + dummycon_register_output_notifier(&fbcon_output_nb); +} +#else +static inline void fbcon_register_output_notifier(void) {} +#endif + static void fbcon_start(void) { + if (deferred_takeover) { + fbcon_register_output_notifier(); + return; + } + if (num_registered_fb) { int i; @@ -3594,6 +3659,13 @@ static void fbcon_exit(void) if (fbcon_has_exited) return; +#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER + if (deferred_takeover) { + dummycon_unregister_output_notifier(&fbcon_output_nb); + deferred_takeover = false; + } +#endif + kfree((void *)softback_buf); softback_buf = 0UL; diff --git a/include/linux/console.h b/include/linux/console.h index dfd6b0e97855..f59f3dbca65c 100644 --- a/include/linux/console.h +++ b/include/linux/console.h @@ -21,6 +21,7 @@ struct console_font_op; struct console_font; struct module; struct tty_struct; +struct notifier_block; /* * this is what the terminal answers to a ESC-Z or csi0c query. @@ -220,4 +221,8 @@ static inline bool vgacon_text_force(void) { return false; } extern void console_init(void); +/* For deferred console takeover */ +void dummycon_register_output_notifier(struct notifier_block *nb); +void dummycon_unregister_output_notifier(struct notifier_block *nb); + #endif /* _LINUX_CONSOLE_H */ |