From 974f48366f5b151f13b91961ec7721e74fb54fa9 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Pali=20Roh=C3=A1r?= Date: Mon, 5 Sep 2022 11:31:17 +0200 Subject: [PATCH] console: Implement flush() function MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit On certain places it is required to flush output print buffers to ensure that text strings were sent to console or serial devices. For example when printing message that U-Boot is going to boot kernel or when U-Boot is going to change baudrate of terminal device. Therefore introduce a new flush() and fflush() functions into console code. These functions will call .flush callback of associated stdio_dev device. As this function may increase U-Boot side, allow to compile U-Boot without this function. For this purpose there is a new config CONSOLE_FLUSH_SUPPORT which is enabled by default and can be disabled. It is a good idea to have this option enabled for all boards which have enough space for it. When option is disabled when U-Boot defines just empty static inline function fflush() to avoid ifdefs in other code. Signed-off-by: Pali Rohár Reviewed-by: Simon Glass --- common/Kconfig | 6 ++++++ common/console.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++++++++ include/_exports.h | 3 +++ include/stdio.h | 15 +++++++++++++ include/stdio_dev.h | 7 ++++++ 5 files changed, 92 insertions(+) diff --git a/common/Kconfig b/common/Kconfig index b776c5c..6591acd 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -186,6 +186,12 @@ config PRE_CON_BUF_ADDR We should consider removing this option and allocating the memory in board_init_f_init_reserve() instead. +config CONSOLE_FLUSH_SUPPORT + bool "Enable console flush support" + default y + help + This enables compilation of flush() function for console flush support. + config CONSOLE_MUX bool "Enable console multiplexing" default y if DM_VIDEO || VIDEO || LCD diff --git a/common/console.c b/common/console.c index e5be6ff..ce0c9b6 100644 --- a/common/console.c +++ b/common/console.c @@ -199,6 +199,7 @@ static int console_setfile(int file, struct stdio_dev * dev) case stdout: gd->jt->putc = putc; gd->jt->puts = puts; + STDIO_DEV_ASSIGN_FLUSH(gd->jt, flush); gd->jt->printf = printf; break; } @@ -364,6 +365,19 @@ static void console_puts(int file, const char *s) } } +#ifdef CONFIG_CONSOLE_FLUSH_SUPPORT +static void console_flush(int file) +{ + int i; + struct stdio_dev *dev; + + for_each_console_dev(i, file, dev) { + if (dev->flush != NULL) + dev->flush(dev); + } +} +#endif + #if CONFIG_IS_ENABLED(SYS_CONSOLE_IS_IN_ENV) static inline void console_doenv(int file, struct stdio_dev *dev) { @@ -413,6 +427,14 @@ static inline void console_puts(int file, const char *s) stdio_devices[file]->puts(stdio_devices[file], s); } +#ifdef CONFIG_CONSOLE_FLUSH_SUPPORT +static inline void console_flush(int file) +{ + if (stdio_devices[file]->flush) + stdio_devices[file]->flush(stdio_devices[file]); +} +#endif + #if CONFIG_IS_ENABLED(SYS_CONSOLE_IS_IN_ENV) static inline void console_doenv(int file, struct stdio_dev *dev) { @@ -526,6 +548,14 @@ void fputs(int file, const char *s) console_puts(file, s); } +#ifdef CONFIG_CONSOLE_FLUSH_SUPPORT +void fflush(int file) +{ + if (file < MAX_FILES) + console_flush(file); +} +#endif + int fprintf(int file, const char *fmt, ...) { va_list args; @@ -740,6 +770,37 @@ void puts(const char *s) } } +#ifdef CONFIG_CONSOLE_FLUSH_SUPPORT +void flush(void) +{ + if (!gd) + return; + + /* sandbox can send characters to stdout before it has a console */ + if (IS_ENABLED(CONFIG_SANDBOX) && !(gd->flags & GD_FLG_SERIAL_READY)) { + os_flush(); + return; + } + + if (IS_ENABLED(CONFIG_DEBUG_UART) && !(gd->flags & GD_FLG_SERIAL_READY)) + return; + + if (IS_ENABLED(CONFIG_SILENT_CONSOLE) && (gd->flags & GD_FLG_SILENT)) + return; + + if (IS_ENABLED(CONFIG_DISABLE_CONSOLE) && (gd->flags & GD_FLG_DISABLE_CONSOLE)) + return; + + if (!gd->have_console) + return; + + if (gd->flags & GD_FLG_DEVINIT) { + /* Send to the standard output */ + fflush(stdout); + } +} +#endif + #ifdef CONFIG_CONSOLE_RECORD int console_record_init(void) { diff --git a/include/_exports.h b/include/_exports.h index f6df8b6..1af946f 100644 --- a/include/_exports.h +++ b/include/_exports.h @@ -12,6 +12,9 @@ EXPORT_FUNC(tstc, int, tstc, void) EXPORT_FUNC(putc, void, putc, const char) EXPORT_FUNC(puts, void, puts, const char *) +#ifdef CONFIG_CONSOLE_FLUSH_SUPPORT + EXPORT_FUNC(flush, void, flush, void) +#endif EXPORT_FUNC(printf, int, printf, const char*, ...) #if (defined(CONFIG_X86) && !defined(CONFIG_X86_64)) || defined(CONFIG_PPC) EXPORT_FUNC(irq_install_handler, void, install_hdlr, diff --git a/include/stdio.h b/include/stdio.h index 1939a48..3241e2d 100644 --- a/include/stdio.h +++ b/include/stdio.h @@ -15,6 +15,11 @@ int tstc(void); defined(CONFIG_SPL_SERIAL)) void putc(const char c); void puts(const char *s); +#ifdef CONFIG_CONSOLE_FLUSH_SUPPORT +void flush(void); +#else +static inline void flush(void) {} +#endif int __printf(1, 2) printf(const char *fmt, ...); int vprintf(const char *fmt, va_list args); #else @@ -26,6 +31,10 @@ static inline void puts(const char *s) { } +static inline void flush(void) +{ +} + static inline int __printf(1, 2) printf(const char *fmt, ...) { return 0; @@ -48,11 +57,17 @@ static inline int vprintf(const char *fmt, va_list args) /* stderr */ #define eputc(c) fputc(stderr, c) #define eputs(s) fputs(stderr, s) +#define eflush() fflush(stderr) #define eprintf(fmt, args...) fprintf(stderr, fmt, ##args) int __printf(2, 3) fprintf(int file, const char *fmt, ...); void fputs(int file, const char *s); void fputc(int file, const char c); +#ifdef CONFIG_CONSOLE_FLUSH_SUPPORT +void fflush(int file); +#else +static inline void fflush(int file) {} +#endif int ftstc(int file); int fgetc(int file); diff --git a/include/stdio_dev.h b/include/stdio_dev.h index 270fa27..3105928 100644 --- a/include/stdio_dev.h +++ b/include/stdio_dev.h @@ -37,6 +37,13 @@ struct stdio_dev { void (*putc)(struct stdio_dev *dev, const char c); /* To put a string (accelerator) */ void (*puts)(struct stdio_dev *dev, const char *s); +#ifdef CONFIG_CONSOLE_FLUSH_SUPPORT + /* To flush output queue */ + void (*flush)(struct stdio_dev *dev); +#define STDIO_DEV_ASSIGN_FLUSH(dev, flush_func) ((dev)->flush = (flush_func)) +#else +#define STDIO_DEV_ASSIGN_FLUSH(dev, flush_func) +#endif /* INPUT functions */ -- 2.7.4