diff options
Diffstat (limited to 'arch/powerpc/kernel/udbg.c')
-rw-r--r-- | arch/powerpc/kernel/udbg.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/udbg.c b/arch/powerpc/kernel/udbg.c new file mode 100644 index 00000000000..0d878e72fc4 --- /dev/null +++ b/arch/powerpc/kernel/udbg.c @@ -0,0 +1,125 @@ +/* + * polling mode stateless debugging stuff, originally for NS16550 Serial Ports + * + * c 2001 PPC 64 Team, IBM Corp + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <stdarg.h> +#include <linux/config.h> +#include <linux/types.h> +#include <linux/sched.h> +#include <linux/console.h> +#include <asm/processor.h> + +void (*udbg_putc)(unsigned char c); +unsigned char (*udbg_getc)(void); +int (*udbg_getc_poll)(void); + +/* udbg library, used by xmon et al */ +void udbg_puts(const char *s) +{ + if (udbg_putc) { + char c; + + if (s && *s != '\0') { + while ((c = *s++) != '\0') + udbg_putc(c); + } + } +#if 0 + else { + printk("%s", s); + } +#endif +} + +int udbg_write(const char *s, int n) +{ + int remain = n; + char c; + + if (!udbg_putc) + return 0; + + if (s && *s != '\0') { + while (((c = *s++) != '\0') && (remain-- > 0)) { + udbg_putc(c); + } + } + + return n - remain; +} + +int udbg_read(char *buf, int buflen) +{ + char c, *p = buf; + int i; + + if (!udbg_getc) + return 0; + + for (i = 0; i < buflen; ++i) { + do { + c = udbg_getc(); + } while (c == 0x11 || c == 0x13); + if (c == 0) + break; + *p++ = c; + } + + return i; +} + +#define UDBG_BUFSIZE 256 +void udbg_printf(const char *fmt, ...) +{ + unsigned char buf[UDBG_BUFSIZE]; + va_list args; + + va_start(args, fmt); + vsnprintf(buf, UDBG_BUFSIZE, fmt, args); + udbg_puts(buf); + va_end(args); +} + +/* + * Early boot console based on udbg + */ +static void udbg_console_write(struct console *con, const char *s, + unsigned int n) +{ + udbg_write(s, n); +} + +static struct console udbg_console = { + .name = "udbg", + .write = udbg_console_write, + .flags = CON_PRINTBUFFER, + .index = -1, +}; + +static int early_console_initialized; + +void __init disable_early_printk(void) +{ + if (!early_console_initialized) + return; + unregister_console(&udbg_console); + early_console_initialized = 0; +} + +/* called by setup_system */ +void register_early_udbg_console(void) +{ + early_console_initialized = 1; + register_console(&udbg_console); +} + +#if 0 /* if you want to use this as a regular output console */ +console_initcall(register_udbg_console); +#endif |