diff options
Diffstat (limited to 'arch/powerpc/kernel/rtas.c')
-rw-r--r-- | arch/powerpc/kernel/rtas.c | 680 |
1 files changed, 680 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c new file mode 100644 index 00000000000..4d22eeeeb91 --- /dev/null +++ b/arch/powerpc/kernel/rtas.c @@ -0,0 +1,680 @@ +/* + * + * 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 <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> +#ifdef CONFIG_PPC64 +#include <asm/systemcfg.h> +#endif + +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; + +/* + * 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. + */ +void call_rtas_display_status(unsigned 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] = (int)c; + + enter_rtas(__pa(args)); + + spin_unlock_irqrestore(&rtas.lock, s); +} + +void call_rtas_display_status_delay(unsigned 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; + udelay(500000); + 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 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); +} + +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) +{ + printk("RTAS system-reboot returned %d\n", + rtas_call(rtas_token("system-reboot"), 0, 1, NULL)); + for (;;); +} + +void rtas_power_off(void) +{ + /* 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) +{ + rtas_power_off(); +} + +/* 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; +} + +#ifdef CONFIG_SMP +/* 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"); +} +#endif + +/* + * Call early during boot, before mem init or bootmem, to retreive 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 (systemcfg->platform == 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); |