rtas.c

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	if (status == RTAS_BUSY) {
		ms = 1;
	} else if (status >= 9900 && status <= 9905) {
		order = status - 9900;
		for (ms = 1; order > 0; order--)
			ms *= 10;
	}

	return ms;
}
EXPORT_SYMBOL(rtas_busy_delay_time);

/* For an RTAS busy status code, perform the hinted delay. */
unsigned int rtas_busy_delay(int status)
{
	unsigned int ms;

	might_sleep();
	ms = rtas_busy_delay_time(status);
	if (ms)
		msleep(ms);

	return ms;
}
EXPORT_SYMBOL(rtas_busy_delay);

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;
}
EXPORT_SYMBOL(rtas_get_power_level);

int rtas_set_power_level(int powerdomain, int level, int *setlevel)
{
	int token = rtas_token("set-power-level");
	int rc;

	if (token == RTAS_UNKNOWN_SERVICE)
		return -ENOENT;

	do {
		rc = rtas_call(token, 2, 2, setlevel, powerdomain, level);
	} while (rtas_busy_delay(rc));

	if (rc < 0)
		return rtas_error_rc(rc);
	return rc;
}
EXPORT_SYMBOL(rtas_set_power_level);

int rtas_get_sensor(int sensor, int index, int *state)
{
	int token = rtas_token("get-sensor-state");
	int rc;

	if (token == RTAS_UNKNOWN_SERVICE)
		return -ENOENT;

	do {
		rc = rtas_call(token, 2, 2, state, sensor, index);
	} while (rtas_busy_delay(rc));

	if (rc < 0)
		return rtas_error_rc(rc);
	return rc;
}
EXPORT_SYMBOL(rtas_get_sensor);

int rtas_set_indicator(int indicator, int index, int new_value)
{
	int token = rtas_token("set-indicator");
	int rc;

	if (token == RTAS_UNKNOWN_SERVICE)
		return -ENOENT;

	do {
		rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);
	} while (rtas_busy_delay(rc));

	if (rc < 0)
		return rtas_error_rc(rc);
	return rc;
}
EXPORT_SYMBOL(rtas_set_indicator);

/*
 * Ignoring RTAS extended delay
 */
int rtas_set_indicator_fast(int indicator, int index, int new_value)
{
	int rc;
	int token = rtas_token("set-indicator");

	if (token == RTAS_UNKNOWN_SERVICE)
		return -ENOENT;

	rc = rtas_call(token, 3, 1, NULL, indicator, index, new_value);

	WARN_ON(rc == -2 || (rc >= 9900 && rc <= 9905));

	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 (panic_timeout)
		return;

	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));
	} while (rtas_busy_delay(status));

	if (status != 0)
		printk(KERN_EMERG "ibm,os-term call failed %d\n",
			       status);
}

static int ibm_suspend_me_token = RTAS_UNKNOWN_SERVICE;
#ifdef CONFIG_PPC_PSERIES
static void rtas_percpu_suspend_me(void *info)
{
	long rc;
	unsigned long msr_save;
	int cpu;
	struct rtas_suspend_me_data *data =
		(struct rtas_suspend_me_data *)info;

	atomic_inc(&data->working);

	/* really need to ensure MSR.EE is off for H_JOIN */
	msr_save = mfmsr();
	mtmsr(msr_save & ~(MSR_EE));

	rc = plpar_hcall_norets(H_JOIN);

	mtmsr(msr_save);

	if (rc == H_SUCCESS) {
		/* This cpu was prodded and the suspend is complete. */
		goto out;
	} else if (rc == H_CONTINUE) {
		/* All other cpus are in H_JOIN, this cpu does
		 * the suspend.
		 */
		printk(KERN_DEBUG "calling ibm,suspend-me on cpu %i\n",
		       smp_processor_id());
		data->error = rtas_call(data->token, 0, 1, NULL);

		if (data->error)
			printk(KERN_DEBUG "ibm,suspend-me returned %d\n",
			       data->error);
	} else {
		printk(KERN_ERR "H_JOIN on cpu %i failed with rc = %ld\n",
		       smp_processor_id(), rc);
		data->error = rc;
	}
	/* This cpu did the suspend or got an error; in either case,
	 * we need to prod all other other cpus out of join state.
	 * Extra prods are harmless.
	 */
	for_each_online_cpu(cpu)
		plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
out:
	if (atomic_dec_return(&data->working) == 0)
		complete(data->complete);
}

static int rtas_ibm_suspend_me(struct rtas_args *args)
{
	long state;
	long rc;
	unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
	struct rtas_suspend_me_data data;
	DECLARE_COMPLETION_ONSTACK(done);

	if (!rtas_service_present("ibm,suspend-me"))
		return -ENOSYS;

	/* Make sure the state is valid */
	rc = plpar_hcall(H_VASI_STATE, retbuf,
			 ((u64)args->args[0] << 32) | args->args[1]);

	state = retbuf[0];

	if (rc) {
		printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned %ld\n",rc);
		return rc;
	} else if (state == H_VASI_ENABLED) {
		args->args[args->nargs] = RTAS_NOT_SUSPENDABLE;
		return 0;
	} else if (state != H_VASI_SUSPENDING) {
		printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned state %ld\n",
		       state);
		args->args[args->nargs] = -1;
		return 0;
	}

	atomic_set(&data.working, 0);
	data.token = rtas_token("ibm,suspend-me");
	data.error = 0;
	data.complete = &done;

	/* Call function on all CPUs.  One of us will make the
	 * rtas call
	 */
	if (on_each_cpu(rtas_percpu_suspend_me, &data, 1, 0))
		data.error = -EINVAL;

	wait_for_completion(&done);

	if (data.error != 0)
		printk(KERN_ERR "Error doing global join\n");

	return data.error;
}
#else /* CONFIG_PPC_PSERIES */
static int rtas_ibm_suspend_me(struct rtas_args *args)
{
	return -ENOSYS;
}
#endif

asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
{
	struct rtas_args args;
	unsigned long flags;
	char *buff_copy, *errbuf = NULL;
	int nargs;
	int rc;

	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;

	if (args.token == RTAS_UNKNOWN_SERVICE)
		return -EINVAL;

	/* Need to handle ibm,suspend_me call specially */
	if (args.token == ibm_suspend_me_token) {
		rc = rtas_ibm_suspend_me(&args);
		if (rc)
			return rc;
		goto copy_return;
	}

	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_return:
	/* Copy out args. */
	if (copy_to_user(uargs->args + nargs,
			 args.args + nargs,
			 args.nret * sizeof(rtas_arg_t)) != 0)
		return -EFAULT;

	return 0;
}

/*
 * 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) {
		const u32 *basep, *entryp, *sizep;

		basep = of_get_property(rtas.dev, "linux,rtas-base", NULL);
		sizep = of_get_property(rtas.dev, "rtas-size", NULL);
		if (basep != NULL && sizep != NULL) {
			rtas.base = *basep;
			rtas.size = *sizep;
			entryp = of_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_is(pseries) && firmware_has_feature(FW_FEATURE_LPAR)) {
		rtas_region = min(lmb.rmo_size, RTAS_INSTANTIATE_MAX);
		ibm_suspend_me_token = rtas_token("ibm,suspend-me");
	}
#endif
	rtas_rmo_buf = lmb_alloc_base(RTAS_RMOBUF_MAX, PAGE_SIZE, rtas_region);

#ifdef CONFIG_RTAS_ERROR_LOGGING
	rtas_last_error_token = rtas_token("rtas-last-error");
#endif
}

int __init early_init_dt_scan_rtas(unsigned long node,
		const char *uname, int depth, void *data)
{
	u32 *basep, *entryp, *sizep;

	if (depth != 1 || strcmp(uname, "rtas") != 0)
		return 0;

	basep  = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
	entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
	sizep  = of_get_flat_dt_prop(node, "rtas-size", NULL);

	if (basep && entryp && sizep) {
		rtas.base = *basep;
		rtas.entry = *entryp;
		rtas.size = *sizep;
	}

#ifdef CONFIG_UDBG_RTAS_CONSOLE
	basep = of_get_flat_dt_prop(node, "put-term-char", NULL);
	if (basep)
		rtas_putchar_token = *basep;

	basep = of_get_flat_dt_prop(node, "get-term-char", NULL);
	if (basep)
		rtas_getchar_token = *basep;

	if (rtas_putchar_token != RTAS_UNKNOWN_SERVICE &&
	    rtas_getchar_token != RTAS_UNKNOWN_SERVICE)
		udbg_init_rtas_console();

#endif

	/* break now */
	return 1;
}