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-rw-r--r--arch/powerpc/kernel/rtas.c680
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);