diff options
Diffstat (limited to '0004-console-fbcon-Add-support-for-deferred-console-takeo.patch')
| -rw-r--r-- | 0004-console-fbcon-Add-support-for-deferred-console-takeo.patch | 322 |
1 files changed, 0 insertions, 322 deletions
diff --git a/0004-console-fbcon-Add-support-for-deferred-console-takeo.patch b/0004-console-fbcon-Add-support-for-deferred-console-takeo.patch deleted file mode 100644 index 36d625ef3..000000000 --- a/0004-console-fbcon-Add-support-for-deferred-console-takeo.patch +++ /dev/null @@ -1,322 +0,0 @@ -From 83d83bebf40132e2d55ec58af666713cc76f9764 Mon Sep 17 00:00:00 2001 -From: Hans de Goede <hdegoede@redhat.com> -Date: Thu, 28 Jun 2018 15:20:30 +0200 -Subject: [PATCH 4/7] console/fbcon: Add support for deferred console takeover - -Currently fbcon claims fbdevs as soon as they are registered and takes over -the console as soon as the first fbdev gets registered. - -This behavior is undesirable in cases where a smooth graphical bootup is -desired, in such cases we typically want the contents of the framebuffer -(typically a vendor logo) to stay in place as is. - -The current solution for this problem (on embedded systems) is to not -enable fbcon. - -This commit adds a new FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER config option, -which when enabled defers fbcon taking over the console from the dummy -console until the first text is displayed on the console. Together with the -"quiet" kernel commandline option, this allows fbcon to still be used -together with a smooth graphical bootup, having it take over the console as -soon as e.g. an error message is logged. - -Note the choice to detect the first console output in the dummycon driver, -rather then handling this entirely inside the fbcon code, was made after -2 failed attempts to handle this entirely inside the fbcon code. The fbcon -code is woven quite tightly into the console code, making this to only -feasible option. - -Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> -Signed-off-by: Hans de Goede <hdegoede@redhat.com> -Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> ---- - Documentation/fb/fbcon.txt | 7 ++++ - drivers/video/console/Kconfig | 11 +++++ - drivers/video/console/dummycon.c | 67 +++++++++++++++++++++++++---- - drivers/video/fbdev/core/fbcon.c | 72 ++++++++++++++++++++++++++++++++ - 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 */ --- -2.18.0 - |