sh: earlyprintk= support and cleanups.

Allow multiple early printk consoles via earlyprintk=.

With this change earlyprintk is no longer enabled by default,
it must be specified on the kernel command line. Optionally
with ,keep to prevent unreg by tty_io.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This commit is contained in:
Paul Mundt 2006-09-27 14:26:53 +09:00
parent e86d6b66f5
commit a80fd21e52
3 changed files with 102 additions and 32 deletions

View File

@ -3,7 +3,7 @@
*
* Copyright (C) 1999, 2000 Niibe Yutaka
* Copyright (C) 2002 M. R. Brown
* Copyright (C) 2004 Paul Mundt
* Copyright (C) 2004 - 2006 Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
@ -49,7 +49,7 @@ static int __init sh_console_setup(struct console *co, char *options)
return 0;
}
static struct console early_console = {
static struct console bios_console = {
.name = "bios",
.write = sh_console_write,
.setup = sh_console_setup,
@ -59,34 +59,43 @@ static struct console early_console = {
#endif
#ifdef CONFIG_EARLY_SCIF_CONSOLE
#include <linux/serial_core.h>
#include "../../../drivers/serial/sh-sci.h"
#ifdef CONFIG_CPU_SH4
#define SCIF_REG 0xffe80000
#elif defined(CONFIG_CPU_SUBTYPE_SH72060)
#define SCIF_REG 0xfffe9800
#else
#error "Undefined SCIF for this subtype"
#endif
static struct uart_port scif_port = {
.mapbase = SCIF_REG,
.membase = (char __iomem *)SCIF_REG,
};
static void scif_sercon_putc(int c)
{
while (!(ctrl_inw(SCIF_REG + 0x10) & 0x20)) ;
while (((sci_in(&scif_port, SCFDR) & 0x1f00 >> 8) == 16))
;
ctrl_outb(c, SCIF_REG + 12);
ctrl_outw((ctrl_inw(SCIF_REG + 0x10) & 0x9f), SCIF_REG + 0x10);
sci_out(&scif_port, SCxTDR, c);
sci_in(&scif_port, SCxSR);
sci_out(&scif_port, SCxSR, 0xf3 & ~(0x20 | 0x40));
while ((sci_in(&scif_port, SCxSR) & 0x40) == 0);
;
if (c == '\n')
scif_sercon_putc('\r');
}
static void scif_sercon_flush(void)
{
ctrl_outw((ctrl_inw(SCIF_REG + 0x10) & 0xbf), SCIF_REG + 0x10);
while (!(ctrl_inw(SCIF_REG + 0x10) & 0x40)) ;
ctrl_outw((ctrl_inw(SCIF_REG + 0x10) & 0xbf), SCIF_REG + 0x10);
}
static void scif_sercon_write(struct console *con, const char *s, unsigned count)
static void scif_sercon_write(struct console *con, const char *s,
unsigned count)
{
while (count-- > 0)
scif_sercon_putc(*s++);
scif_sercon_flush();
}
static int __init scif_sercon_setup(struct console *con, char *options)
@ -96,7 +105,7 @@ static int __init scif_sercon_setup(struct console *con, char *options)
return 0;
}
static struct console early_console = {
static struct console scif_console = {
.name = "sercon",
.write = scif_sercon_write,
.setup = scif_sercon_setup,
@ -104,7 +113,7 @@ static struct console early_console = {
.index = -1,
};
void scif_sercon_init(int baud)
static void scif_sercon_init(int baud)
{
ctrl_outw(0, SCIF_REG + 8);
ctrl_outw(0, SCIF_REG);
@ -122,16 +131,61 @@ void scif_sercon_init(int baud)
}
#endif
void __init enable_early_printk(void)
{
#ifdef CONFIG_EARLY_SCIF_CONSOLE
scif_sercon_init(115200);
/*
* Setup a default console, if more than one is compiled in, rely on the
* earlyprintk= parsing to give priority.
*/
static struct console *early_console =
#ifdef CONFIG_SH_STANDARD_BIOS
&bios_console
#elif defined(CONFIG_EARLY_SCIF_CONSOLE)
&scif_console
#else
NULL
#endif
register_console(&early_console);
}
;
void disable_early_printk(void)
static int __initdata keep_early;
int __init setup_early_printk(char *opt)
{
unregister_console(&early_console);
}
char *space;
char buf[256];
strlcpy(buf, opt, sizeof(buf));
space = strchr(buf, ' ');
if (space)
*space = 0;
if (strstr(buf, "keep"))
keep_early = 1;
#ifdef CONFIG_SH_STANDARD_BIOS
if (!strncmp(buf, "bios", 4))
early_console = &bios_console;
#endif
#if defined(CONFIG_EARLY_SCIF_CONSOLE)
if (!strncmp(buf, "serial", 6)) {
early_console = &scif_console;
#ifdef CONFIG_CPU_SH4
scif_sercon_init(115200);
#endif
}
#endif
if (likely(early_console))
register_console(early_console);
return 1;
}
__setup("earlyprintk=", setup_early_printk);
void __init disable_early_printk(void)
{
if (!keep_early) {
printk("disabling early console\n");
unregister_console(early_console);
} else
printk("keeping early console\n");
}

View File

@ -145,6 +145,24 @@ static inline void parse_cmdline (char ** cmdline_p, char mv_name[MV_NAME_SIZE],
memory_end = memory_start + mem_size;
}
}
#ifdef CONFIG_EARLY_PRINTK
if (c == ' ' && !memcmp(from, "earlyprintk=", 12)) {
char *ep_end;
if (to != command_line)
to--;
from += 12;
ep_end = strchr(from, ' ');
setup_early_printk(from);
printk("early console enabled\n");
from = ep_end;
}
#endif
if (c == ' ' && !memcmp(from, "sh_mv=", 6)) {
char* mv_end;
char* mv_comma;
@ -245,11 +263,7 @@ void __init setup_arch(char **cmdline_p)
unsigned long bootmap_size;
unsigned long start_pfn, max_pfn, max_low_pfn;
#ifdef CONFIG_EARLY_PRINTK
extern void enable_early_printk(void);
enable_early_printk();
#endif
#ifdef CONFIG_CMDLINE_BOOL
strcpy(COMMAND_LINE, CONFIG_CMDLINE);
#endif

View File

@ -4,5 +4,7 @@
#define COMMAND_LINE_SIZE 256
int setup_early_printk(char *);
#endif /* _SH_SETUP_H */
#endif /* __KERNEL__ */