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linux/arch/powerpc/kernel/rtas.c
Michael Ellerman 296167ae17 [PATCH] powerpc: Make early debugging configurable via Kconfig
This patch adds Kconfig entries to control the early debugging options,
currently in setup_64.c.

Doing this via Kconfig rather than #defines means you can have one source tree,
which is buildable for multiple platforms - and you can enable the correct
early debug option for each platform via .config.

I made udbg_early_init() a static inline because otherwise GCC is to daft to
optimise it away when debugging is off.

Now that we have udbg_init_rtas() we can make call_rtas_display_status* static.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-11 14:48:26 +11:00

700 lines
16 KiB
C

/*
*
* Procedures for interfacing to the RTAS on CHRP machines.
*
* Peter Bergner, IBM March 2001.
* Copyright (C) 2001 IBM.
*
* 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/kernel.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <asm/prom.h>
#include <asm/rtas.h>
#include <asm/semaphore.h>
#include <asm/machdep.h>
#include <asm/page.h>
#include <asm/param.h>
#include <asm/system.h>
#include <asm/delay.h>
#include <asm/uaccess.h>
#include <asm/lmb.h>
#include <asm/udbg.h>
struct rtas_t rtas = {
.lock = SPIN_LOCK_UNLOCKED
};
EXPORT_SYMBOL(rtas);
DEFINE_SPINLOCK(rtas_data_buf_lock);
char rtas_data_buf[RTAS_DATA_BUF_SIZE] __cacheline_aligned;
unsigned long rtas_rmo_buf;
/*
* If non-NULL, this gets called when the kernel terminates.
* This is done like this so rtas_flash can be a module.
*/
void (*rtas_flash_term_hook)(int);
EXPORT_SYMBOL(rtas_flash_term_hook);
/*
* call_rtas_display_status and call_rtas_display_status_delay
* are designed only for very early low-level debugging, which
* is why the token is hard-coded to 10.
*/
static void call_rtas_display_status(char c)
{
struct rtas_args *args = &rtas.args;
unsigned long s;
if (!rtas.base)
return;
spin_lock_irqsave(&rtas.lock, s);
args->token = 10;
args->nargs = 1;
args->nret = 1;
args->rets = (rtas_arg_t *)&(args->args[1]);
args->args[0] = (unsigned char)c;
enter_rtas(__pa(args));
spin_unlock_irqrestore(&rtas.lock, s);
}
static void call_rtas_display_status_delay(char c)
{
static int pending_newline = 0; /* did last write end with unprinted newline? */
static int width = 16;
if (c == '\n') {
while (width-- > 0)
call_rtas_display_status(' ');
width = 16;
mdelay(500);
pending_newline = 1;
} else {
if (pending_newline) {
call_rtas_display_status('\r');
call_rtas_display_status('\n');
}
pending_newline = 0;
if (width--) {
call_rtas_display_status(c);
udelay(10000);
}
}
}
void __init udbg_init_rtas(void)
{
udbg_putc = call_rtas_display_status_delay;
}
void rtas_progress(char *s, unsigned short hex)
{
struct device_node *root;
int width, *p;
char *os;
static int display_character, set_indicator;
static int display_width, display_lines, *row_width, form_feed;
static DEFINE_SPINLOCK(progress_lock);
static int current_line;
static int pending_newline = 0; /* did last write end with unprinted newline? */
if (!rtas.base)
return;
if (display_width == 0) {
display_width = 0x10;
if ((root = find_path_device("/rtas"))) {
if ((p = (unsigned int *)get_property(root,
"ibm,display-line-length", NULL)))
display_width = *p;
if ((p = (unsigned int *)get_property(root,
"ibm,form-feed", NULL)))
form_feed = *p;
if ((p = (unsigned int *)get_property(root,
"ibm,display-number-of-lines", NULL)))
display_lines = *p;
row_width = (unsigned int *)get_property(root,
"ibm,display-truncation-length", NULL);
}
display_character = rtas_token("display-character");
set_indicator = rtas_token("set-indicator");
}
if (display_character == RTAS_UNKNOWN_SERVICE) {
/* use hex display if available */
if (set_indicator != RTAS_UNKNOWN_SERVICE)
rtas_call(set_indicator, 3, 1, NULL, 6, 0, hex);
return;
}
spin_lock(&progress_lock);
/*
* Last write ended with newline, but we didn't print it since
* it would just clear the bottom line of output. Print it now
* instead.
*
* If no newline is pending and form feed is supported, clear the
* display with a form feed; otherwise, print a CR to start output
* at the beginning of the line.
*/
if (pending_newline) {
rtas_call(display_character, 1, 1, NULL, '\r');
rtas_call(display_character, 1, 1, NULL, '\n');
pending_newline = 0;
} else {
current_line = 0;
if (form_feed)
rtas_call(display_character, 1, 1, NULL,
(char)form_feed);
else
rtas_call(display_character, 1, 1, NULL, '\r');
}
if (row_width)
width = row_width[current_line];
else
width = display_width;
os = s;
while (*os) {
if (*os == '\n' || *os == '\r') {
/* If newline is the last character, save it
* until next call to avoid bumping up the
* display output.
*/
if (*os == '\n' && !os[1]) {
pending_newline = 1;
current_line++;
if (current_line > display_lines-1)
current_line = display_lines-1;
spin_unlock(&progress_lock);
return;
}
/* RTAS wants CR-LF, not just LF */
if (*os == '\n') {
rtas_call(display_character, 1, 1, NULL, '\r');
rtas_call(display_character, 1, 1, NULL, '\n');
} else {
/* CR might be used to re-draw a line, so we'll
* leave it alone and not add LF.
*/
rtas_call(display_character, 1, 1, NULL, *os);
}
if (row_width)
width = row_width[current_line];
else
width = display_width;
} else {
width--;
rtas_call(display_character, 1, 1, NULL, *os);
}
os++;
/* if we overwrite the screen length */
if (width <= 0)
while ((*os != 0) && (*os != '\n') && (*os != '\r'))
os++;
}
spin_unlock(&progress_lock);
}
EXPORT_SYMBOL(rtas_progress); /* needed by rtas_flash module */
int rtas_token(const char *service)
{
int *tokp;
if (rtas.dev == NULL)
return RTAS_UNKNOWN_SERVICE;
tokp = (int *) get_property(rtas.dev, service, NULL);
return tokp ? *tokp : RTAS_UNKNOWN_SERVICE;
}
#ifdef CONFIG_RTAS_ERROR_LOGGING
/*
* Return the firmware-specified size of the error log buffer
* for all rtas calls that require an error buffer argument.
* This includes 'check-exception' and 'rtas-last-error'.
*/
int rtas_get_error_log_max(void)
{
static int rtas_error_log_max;
if (rtas_error_log_max)
return rtas_error_log_max;
rtas_error_log_max = rtas_token ("rtas-error-log-max");
if ((rtas_error_log_max == RTAS_UNKNOWN_SERVICE) ||
(rtas_error_log_max > RTAS_ERROR_LOG_MAX)) {
printk (KERN_WARNING "RTAS: bad log buffer size %d\n",
rtas_error_log_max);
rtas_error_log_max = RTAS_ERROR_LOG_MAX;
}
return rtas_error_log_max;
}
EXPORT_SYMBOL(rtas_get_error_log_max);
char rtas_err_buf[RTAS_ERROR_LOG_MAX];
int rtas_last_error_token;
/** Return a copy of the detailed error text associated with the
* most recent failed call to rtas. Because the error text
* might go stale if there are any other intervening rtas calls,
* this routine must be called atomically with whatever produced
* the error (i.e. with rtas.lock still held from the previous call).
*/
static char *__fetch_rtas_last_error(char *altbuf)
{
struct rtas_args err_args, save_args;
u32 bufsz;
char *buf = NULL;
if (rtas_last_error_token == -1)
return NULL;
bufsz = rtas_get_error_log_max();
err_args.token = rtas_last_error_token;
err_args.nargs = 2;
err_args.nret = 1;
err_args.args[0] = (rtas_arg_t)__pa(rtas_err_buf);
err_args.args[1] = bufsz;
err_args.args[2] = 0;
save_args = rtas.args;
rtas.args = err_args;
enter_rtas(__pa(&rtas.args));
err_args = rtas.args;
rtas.args = save_args;
/* Log the error in the unlikely case that there was one. */
if (unlikely(err_args.args[2] == 0)) {
if (altbuf) {
buf = altbuf;
} else {
buf = rtas_err_buf;
if (mem_init_done)
buf = kmalloc(RTAS_ERROR_LOG_MAX, GFP_ATOMIC);
}
if (buf)
memcpy(buf, rtas_err_buf, RTAS_ERROR_LOG_MAX);
}
return buf;
}
#define get_errorlog_buffer() kmalloc(RTAS_ERROR_LOG_MAX, GFP_KERNEL)
#else /* CONFIG_RTAS_ERROR_LOGGING */
#define __fetch_rtas_last_error(x) NULL
#define get_errorlog_buffer() NULL
#endif
int rtas_call(int token, int nargs, int nret, int *outputs, ...)
{
va_list list;
int i;
unsigned long s;
struct rtas_args *rtas_args;
char *buff_copy = NULL;
int ret;
if (token == RTAS_UNKNOWN_SERVICE)
return -1;
/* Gotta do something different here, use global lock for now... */
spin_lock_irqsave(&rtas.lock, s);
rtas_args = &rtas.args;
rtas_args->token = token;
rtas_args->nargs = nargs;
rtas_args->nret = nret;
rtas_args->rets = (rtas_arg_t *)&(rtas_args->args[nargs]);
va_start(list, outputs);
for (i = 0; i < nargs; ++i)
rtas_args->args[i] = va_arg(list, rtas_arg_t);
va_end(list);
for (i = 0; i < nret; ++i)
rtas_args->rets[i] = 0;
enter_rtas(__pa(rtas_args));
/* A -1 return code indicates that the last command couldn't
be completed due to a hardware error. */
if (rtas_args->rets[0] == -1)
buff_copy = __fetch_rtas_last_error(NULL);
if (nret > 1 && outputs != NULL)
for (i = 0; i < nret-1; ++i)
outputs[i] = rtas_args->rets[i+1];
ret = (nret > 0)? rtas_args->rets[0]: 0;
/* Gotta do something different here, use global lock for now... */
spin_unlock_irqrestore(&rtas.lock, s);
if (buff_copy) {
log_error(buff_copy, ERR_TYPE_RTAS_LOG, 0);
if (mem_init_done)
kfree(buff_copy);
}
return ret;
}
/* Given an RTAS status code of 990n compute the hinted delay of 10^n
* (last digit) milliseconds. For now we bound at n=5 (100 sec).
*/
unsigned int rtas_extended_busy_delay_time(int status)
{
int order = status - 9900;
unsigned long ms;
if (order < 0)
order = 0; /* RTC depends on this for -2 clock busy */
else if (order > 5)
order = 5; /* bound */
/* Use microseconds for reasonable accuracy */
for (ms = 1; order > 0; order--)
ms *= 10;
return ms;
}
int rtas_error_rc(int rtas_rc)
{
int rc;
switch (rtas_rc) {
case -1: /* Hardware Error */
rc = -EIO;
break;
case -3: /* Bad indicator/domain/etc */
rc = -EINVAL;
break;
case -9000: /* Isolation error */
rc = -EFAULT;
break;
case -9001: /* Outstanding TCE/PTE */
rc = -EEXIST;
break;
case -9002: /* No usable slot */
rc = -ENODEV;
break;
default:
printk(KERN_ERR "%s: unexpected RTAS error %d\n",
__FUNCTION__, rtas_rc);
rc = -ERANGE;
break;
}
return rc;
}
int rtas_get_power_level(int powerdomain, int *level)
{
int token = rtas_token("get-power-level");
int rc;
if (token == RTAS_UNKNOWN_SERVICE)
return -ENOENT;
while ((rc = rtas_call(token, 1, 2, level, powerdomain)) == RTAS_BUSY)
udelay(1);
if (rc < 0)
return rtas_error_rc(rc);
return rc;
}
int rtas_set_power_level(int powerdomain, int level, int *setlevel)
{
int token = rtas_token("set-power-level");
unsigned int wait_time;
int rc;
if (token == RTAS_UNKNOWN_SERVICE)
return -ENOENT;
while (1) {
rc = rtas_call(token, 2, 2, setlevel, powerdomain, level);
if (rc == RTAS_BUSY)
udelay(1);
else if (rtas_is_extended_busy(rc)) {
wait_time = rtas_extended_busy_delay_time(rc);
udelay(wait_time * 1000);
} else
break;
}
if (rc < 0)
return rtas_error_rc(rc);
return rc;
}
int rtas_get_sensor(int sensor, int index, int *state)
{
int token = rtas_token("get-sensor-state");
unsigned int wait_time;
int rc;
if (token == RTAS_UNKNOWN_SERVICE)
return -ENOENT;
while (1) {
rc = rtas_call(token, 2, 2, state, sensor, index);
if (rc == RTAS_BUSY)
udelay(1);
else if (rtas_is_extended_busy(rc)) {
wait_time = rtas_extended_busy_delay_time(rc);
udelay(wait_time * 1000);
} else
break;
}
if (rc < 0)
return rtas_error_rc(rc);
return rc;
}
int rtas_set_indicator(int indicator, int index, int new_value)
{
int token = rtas_token("set-indicator");
unsigned int wait_time;
int rc;
if (token == RTAS_UNKNOWN_SERVICE)
return -ENOENT;
while (1) {
rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
if (rc == RTAS_BUSY)
udelay(1);
else if (rtas_is_extended_busy(rc)) {
wait_time = rtas_extended_busy_delay_time(rc);
udelay(wait_time * 1000);
}
else
break;
}
if (rc < 0)
return rtas_error_rc(rc);
return rc;
}
void rtas_restart(char *cmd)
{
if (rtas_flash_term_hook)
rtas_flash_term_hook(SYS_RESTART);
printk("RTAS system-reboot returned %d\n",
rtas_call(rtas_token("system-reboot"), 0, 1, NULL));
for (;;);
}
void rtas_power_off(void)
{
if (rtas_flash_term_hook)
rtas_flash_term_hook(SYS_POWER_OFF);
/* allow power on only with power button press */
printk("RTAS power-off returned %d\n",
rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
for (;;);
}
void rtas_halt(void)
{
if (rtas_flash_term_hook)
rtas_flash_term_hook(SYS_HALT);
/* allow power on only with power button press */
printk("RTAS power-off returned %d\n",
rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
for (;;);
}
/* Must be in the RMO region, so we place it here */
static char rtas_os_term_buf[2048];
void rtas_os_term(char *str)
{
int status;
if (RTAS_UNKNOWN_SERVICE == rtas_token("ibm,os-term"))
return;
snprintf(rtas_os_term_buf, 2048, "OS panic: %s", str);
do {
status = rtas_call(rtas_token("ibm,os-term"), 1, 1, NULL,
__pa(rtas_os_term_buf));
if (status == RTAS_BUSY)
udelay(1);
else if (status != 0)
printk(KERN_EMERG "ibm,os-term call failed %d\n",
status);
} while (status == RTAS_BUSY);
}
asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
{
struct rtas_args args;
unsigned long flags;
char *buff_copy, *errbuf = NULL;
int nargs;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0)
return -EFAULT;
nargs = args.nargs;
if (nargs > ARRAY_SIZE(args.args)
|| args.nret > ARRAY_SIZE(args.args)
|| nargs + args.nret > ARRAY_SIZE(args.args))
return -EINVAL;
/* Copy in args. */
if (copy_from_user(args.args, uargs->args,
nargs * sizeof(rtas_arg_t)) != 0)
return -EFAULT;
buff_copy = get_errorlog_buffer();
spin_lock_irqsave(&rtas.lock, flags);
rtas.args = args;
enter_rtas(__pa(&rtas.args));
args = rtas.args;
args.rets = &args.args[nargs];
/* A -1 return code indicates that the last command couldn't
be completed due to a hardware error. */
if (args.rets[0] == -1)
errbuf = __fetch_rtas_last_error(buff_copy);
spin_unlock_irqrestore(&rtas.lock, flags);
if (buff_copy) {
if (errbuf)
log_error(errbuf, ERR_TYPE_RTAS_LOG, 0);
kfree(buff_copy);
}
/* Copy out args. */
if (copy_to_user(uargs->args + nargs,
args.args + nargs,
args.nret * sizeof(rtas_arg_t)) != 0)
return -EFAULT;
return 0;
}
/* This version can't take the spinlock, because it never returns */
struct rtas_args rtas_stop_self_args = {
/* The token is initialized for real in setup_system() */
.token = RTAS_UNKNOWN_SERVICE,
.nargs = 0,
.nret = 1,
.rets = &rtas_stop_self_args.args[0],
};
void rtas_stop_self(void)
{
struct rtas_args *rtas_args = &rtas_stop_self_args;
local_irq_disable();
BUG_ON(rtas_args->token == RTAS_UNKNOWN_SERVICE);
printk("cpu %u (hwid %u) Ready to die...\n",
smp_processor_id(), hard_smp_processor_id());
enter_rtas(__pa(rtas_args));
panic("Alas, I survived.\n");
}
/*
* Call early during boot, before mem init or bootmem, to retrieve the RTAS
* informations from the device-tree and allocate the RMO buffer for userland
* accesses.
*/
void __init rtas_initialize(void)
{
unsigned long rtas_region = RTAS_INSTANTIATE_MAX;
/* Get RTAS dev node and fill up our "rtas" structure with infos
* about it.
*/
rtas.dev = of_find_node_by_name(NULL, "rtas");
if (rtas.dev) {
u32 *basep, *entryp;
u32 *sizep;
basep = (u32 *)get_property(rtas.dev, "linux,rtas-base", NULL);
sizep = (u32 *)get_property(rtas.dev, "rtas-size", NULL);
if (basep != NULL && sizep != NULL) {
rtas.base = *basep;
rtas.size = *sizep;
entryp = (u32 *)get_property(rtas.dev, "linux,rtas-entry", NULL);
if (entryp == NULL) /* Ugh */
rtas.entry = rtas.base;
else
rtas.entry = *entryp;
} else
rtas.dev = NULL;
}
if (!rtas.dev)
return;
/* If RTAS was found, allocate the RMO buffer for it and look for
* the stop-self token if any
*/
#ifdef CONFIG_PPC64
if (_machine == PLATFORM_PSERIES_LPAR)
rtas_region = min(lmb.rmo_size, RTAS_INSTANTIATE_MAX);
#endif
rtas_rmo_buf = lmb_alloc_base(RTAS_RMOBUF_MAX, PAGE_SIZE, rtas_region);
#ifdef CONFIG_HOTPLUG_CPU
rtas_stop_self_args.token = rtas_token("stop-self");
#endif /* CONFIG_HOTPLUG_CPU */
#ifdef CONFIG_RTAS_ERROR_LOGGING
rtas_last_error_token = rtas_token("rtas-last-error");
#endif
}
EXPORT_SYMBOL(rtas_token);
EXPORT_SYMBOL(rtas_call);
EXPORT_SYMBOL(rtas_data_buf);
EXPORT_SYMBOL(rtas_data_buf_lock);
EXPORT_SYMBOL(rtas_extended_busy_delay_time);
EXPORT_SYMBOL(rtas_get_sensor);
EXPORT_SYMBOL(rtas_get_power_level);
EXPORT_SYMBOL(rtas_set_power_level);
EXPORT_SYMBOL(rtas_set_indicator);