linux/linux-5.18.11/arch/powerpc/kernel/udbg.c

179 lines
3.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* polling mode stateless debugging stuff, originally for NS16550 Serial Ports
*
* c 2001 PPC 64 Team, IBM Corp
*/
#include <linux/stdarg.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/console.h>
#include <linux/init.h>
#include <asm/processor.h>
#include <asm/udbg.h>
void (*udbg_putc)(char c);
void (*udbg_flush)(void);
int (*udbg_getc)(void);
int (*udbg_getc_poll)(void);
/*
* Early debugging facilities. You can enable _one_ of these via .config,
* if you do so your kernel _will not boot_ on anything else. Be careful.
*/
void __init udbg_early_init(void)
{
#if defined(CONFIG_PPC_EARLY_DEBUG_LPAR)
/* For LPAR machines that have an HVC console on vterm 0 */
udbg_init_debug_lpar();
#elif defined(CONFIG_PPC_EARLY_DEBUG_LPAR_HVSI)
/* For LPAR machines that have an HVSI console on vterm 0 */
udbg_init_debug_lpar_hvsi();
#elif defined(CONFIG_PPC_EARLY_DEBUG_G5)
/* For use on Apple G5 machines */
udbg_init_pmac_realmode();
#elif defined(CONFIG_PPC_EARLY_DEBUG_RTAS_PANEL)
/* RTAS panel debug */
udbg_init_rtas_panel();
#elif defined(CONFIG_PPC_EARLY_DEBUG_RTAS_CONSOLE)
/* RTAS console debug */
udbg_init_rtas_console();
#elif defined(CONFIG_PPC_EARLY_DEBUG_MAPLE)
/* Maple real mode debug */
udbg_init_maple_realmode();
#elif defined(CONFIG_PPC_EARLY_DEBUG_PAS_REALMODE)
udbg_init_pas_realmode();
#elif defined(CONFIG_PPC_EARLY_DEBUG_BOOTX)
udbg_init_btext();
#elif defined(CONFIG_PPC_EARLY_DEBUG_44x)
/* PPC44x debug */
udbg_init_44x_as1();
#elif defined(CONFIG_PPC_EARLY_DEBUG_40x)
/* PPC40x debug */
udbg_init_40x_realmode();
#elif defined(CONFIG_PPC_EARLY_DEBUG_CPM)
udbg_init_cpm();
#elif defined(CONFIG_PPC_EARLY_DEBUG_USBGECKO)
udbg_init_usbgecko();
#elif defined(CONFIG_PPC_EARLY_DEBUG_MEMCONS)
/* In memory console */
udbg_init_memcons();
#elif defined(CONFIG_PPC_EARLY_DEBUG_EHV_BC)
udbg_init_ehv_bc();
#elif defined(CONFIG_PPC_EARLY_DEBUG_PS3GELIC)
udbg_init_ps3gelic();
#elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_RAW)
udbg_init_debug_opal_raw();
#elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI)
udbg_init_debug_opal_hvsi();
#endif
#ifdef CONFIG_PPC_EARLY_DEBUG
console_loglevel = CONSOLE_LOGLEVEL_DEBUG;
register_early_udbg_console();
#endif
}
/* 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 (udbg_flush)
udbg_flush();
}
#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);
}
}
if (udbg_flush)
udbg_flush();
return n - remain;
}
#define UDBG_BUFSIZE 256
void udbg_printf(const char *fmt, ...)
{
if (udbg_putc) {
char buf[UDBG_BUFSIZE];
va_list args;
va_start(args, fmt);
vsnprintf(buf, UDBG_BUFSIZE, fmt, args);
udbg_puts(buf);
va_end(args);
}
}
void __init udbg_progress(char *s, unsigned short hex)
{
udbg_puts(s);
udbg_puts("\n");
}
/*
* 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 | CON_ENABLED | CON_BOOT | CON_ANYTIME,
.index = 0,
};
/*
* Called by setup_system after ppc_md->probe and ppc_md->early_init.
* Call it again after setting udbg_putc in ppc_md->setup_arch.
*/
void __init register_early_udbg_console(void)
{
if (early_console)
return;
if (!udbg_putc)
return;
if (strstr(boot_command_line, "udbg-immortal")) {
printk(KERN_INFO "early console immortal !\n");
udbg_console.flags &= ~CON_BOOT;
}
early_console = &udbg_console;
register_console(&udbg_console);
}
#if 0 /* if you want to use this as a regular output console */
console_initcall(register_udbg_console);
#endif