initial_commit

1 files changed, 1001 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/powerdomain.c b/arch/arm/mach-omap2/powerdomain.c
new file mode 100644
index 00000000..9af08473
--- /dev/null
+++ b/arch/arm/mach-omap2/powerdomain.c
@@ -0,0 +1,1001 @@
+/*
+ * OMAP powerdomain control
+ *
+ * Copyright (C) 2007-2008 Texas Instruments, Inc.
+ * Copyright (C) 2007-2011 Nokia Corporation
+ *
+ * Written by Paul Walmsley
+ * Added OMAP4 specific support by Abhijit Pagare <abhijitpagare@ti.com>
+ * State counting code by Tero Kristo <tero.kristo@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#undef DEBUG
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <trace/events/power.h>
+
+#include "cm2xxx_3xxx.h"
+#include "prcm44xx.h"
+#include "cm44xx.h"
+#include "prm2xxx_3xxx.h"
+#include "prm44xx.h"
+
+#include <asm/cpu.h>
+#include <plat/cpu.h>
+#include "powerdomain.h"
+#include "clockdomain.h"
+#include <plat/prcm.h>
+
+#include "pm.h"
+
+#define PWRDM_TRACE_STATES_FLAG	(1<<31)
+
+enum {
+	PWRDM_STATE_NOW = 0,
+	PWRDM_STATE_PREV,
+};
+
+
+/* pwrdm_list contains all registered struct powerdomains */
+static LIST_HEAD(pwrdm_list);
+
+static struct pwrdm_ops *arch_pwrdm;
+
+/* Private functions */
+
+static struct powerdomain *_pwrdm_lookup(const char *name)
+{
+	struct powerdomain *pwrdm, *temp_pwrdm;
+
+	pwrdm = NULL;
+
+	list_for_each_entry(temp_pwrdm, &pwrdm_list, node) {
+		if (!strcmp(name, temp_pwrdm->name)) {
+			pwrdm = temp_pwrdm;
+			break;
+		}
+	}
+
+	return pwrdm;
+}
+
+/**
+ * _pwrdm_register - register a powerdomain
+ * @pwrdm: struct powerdomain * to register
+ *
+ * Adds a powerdomain to the internal powerdomain list.  Returns
+ * -EINVAL if given a null pointer, -EEXIST if a powerdomain is
+ * already registered by the provided name, or 0 upon success.
+ */
+static int _pwrdm_register(struct powerdomain *pwrdm)
+{
+	int i;
+
+	if (!pwrdm || !pwrdm->name)
+		return -EINVAL;
+
+	if (!omap_chip_is(pwrdm->omap_chip))
+		return -EINVAL;
+
+	if (cpu_is_omap44xx() &&
+	    pwrdm->prcm_partition == OMAP4430_INVALID_PRCM_PARTITION) {
+		pr_err("powerdomain: %s: missing OMAP4 PRCM partition ID\n",
+		       pwrdm->name);
+		return -EINVAL;
+	}
+
+	if (_pwrdm_lookup(pwrdm->name))
+		return -EEXIST;
+
+	list_add(&pwrdm->node, &pwrdm_list);
+
+	/* Initialize the powerdomain's state counter */
+	for (i = 0; i < PWRDM_MAX_PWRSTS; i++)
+		pwrdm->state_counter[i] = 0;
+
+	pwrdm->ret_logic_off_counter = 0;
+	for (i = 0; i < pwrdm->banks; i++)
+		pwrdm->ret_mem_off_counter[i] = 0;
+
+	pwrdm_wait_transition(pwrdm);
+	pwrdm->state = pwrdm_read_pwrst(pwrdm);
+	pwrdm->state_counter[pwrdm->state] = 1;
+
+	pr_debug("powerdomain: registered %s\n", pwrdm->name);
+
+	return 0;
+}
+
+static void _update_logic_membank_counters(struct powerdomain *pwrdm)
+{
+	int i;
+	u8 prev_logic_pwrst, prev_mem_pwrst;
+
+	prev_logic_pwrst = pwrdm_read_prev_logic_pwrst(pwrdm);
+	if ((pwrdm->pwrsts_logic_ret == PWRSTS_OFF_RET) &&
+	    (prev_logic_pwrst == PWRDM_POWER_OFF))
+		pwrdm->ret_logic_off_counter++;
+
+	for (i = 0; i < pwrdm->banks; i++) {
+		prev_mem_pwrst = pwrdm_read_prev_mem_pwrst(pwrdm, i);
+
+		if ((pwrdm->pwrsts_mem_ret[i] == PWRSTS_OFF_RET) &&
+		    (prev_mem_pwrst == PWRDM_POWER_OFF))
+			pwrdm->ret_mem_off_counter[i]++;
+	}
+}
+
+static int _pwrdm_state_switch(struct powerdomain *pwrdm, int flag)
+{
+
+	int prev, state, trace_state = 0;
+
+	if (pwrdm == NULL)
+		return -EINVAL;
+
+	state = pwrdm_read_pwrst(pwrdm);
+
+	switch (flag) {
+	case PWRDM_STATE_NOW:
+		prev = pwrdm->state;
+		break;
+	case PWRDM_STATE_PREV:
+		prev = pwrdm_read_prev_pwrst(pwrdm);
+		if (pwrdm->state != prev)
+			pwrdm->state_counter[prev]++;
+		if (prev == PWRDM_POWER_RET)
+			_update_logic_membank_counters(pwrdm);
+		/*
+		 * If the power domain did not hit the desired state,
+		 * generate a trace event with both the desired and hit states
+		 */
+		if (state != prev) {
+			trace_state = (PWRDM_TRACE_STATES_FLAG |
+				       ((state & OMAP_POWERSTATE_MASK) << 8) |
+				       ((prev & OMAP_POWERSTATE_MASK) << 0));
+			trace_power_domain_target(pwrdm->name, trace_state,
+						  smp_processor_id());
+		}
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (state != prev)
+		pwrdm->state_counter[state]++;
+
+	pm_dbg_update_time(pwrdm, prev);
+
+	pwrdm->state = state;
+
+	return 0;
+}
+
+static int _pwrdm_pre_transition_cb(struct powerdomain *pwrdm, void *unused)
+{
+	pwrdm_clear_all_prev_pwrst(pwrdm);
+	_pwrdm_state_switch(pwrdm, PWRDM_STATE_NOW);
+	return 0;
+}
+
+static int _pwrdm_post_transition_cb(struct powerdomain *pwrdm, void *unused)
+{
+	_pwrdm_state_switch(pwrdm, PWRDM_STATE_PREV);
+	return 0;
+}
+
+/* Public functions */
+
+/**
+ * pwrdm_init - set up the powerdomain layer
+ * @pwrdm_list: array of struct powerdomain pointers to register
+ * @custom_funcs: func pointers for arch specific implementations
+ *
+ * Loop through the array of powerdomains @pwrdm_list, registering all
+ * that are available on the current CPU. If pwrdm_list is supplied
+ * and not null, all of the referenced powerdomains will be
+ * registered.  No return value.  XXX pwrdm_list is not really a
+ * "list"; it is an array.  Rename appropriately.
+ */
+void pwrdm_init(struct powerdomain **pwrdm_list, struct pwrdm_ops *custom_funcs)
+{
+	struct powerdomain **p = NULL;
+
+	if (!custom_funcs)
+		WARN(1, "powerdomain: No custom pwrdm functions registered\n");
+	else
+		arch_pwrdm = custom_funcs;
+
+	if (pwrdm_list) {
+		for (p = pwrdm_list; *p; p++)
+			_pwrdm_register(*p);
+	}
+}
+
+/**
+ * pwrdm_lookup - look up a powerdomain by name, return a pointer
+ * @name: name of powerdomain
+ *
+ * Find a registered powerdomain by its name @name.  Returns a pointer
+ * to the struct powerdomain if found, or NULL otherwise.
+ */
+struct powerdomain *pwrdm_lookup(const char *name)
+{
+	struct powerdomain *pwrdm;
+
+	if (!name)
+		return NULL;
+
+	pwrdm = _pwrdm_lookup(name);
+
+	return pwrdm;
+}
+
+/**
+ * pwrdm_for_each - call function on each registered clockdomain
+ * @fn: callback function *
+ *
+ * Call the supplied function @fn for each registered powerdomain.
+ * The callback function @fn can return anything but 0 to bail out
+ * early from the iterator.  Returns the last return value of the
+ * callback function, which should be 0 for success or anything else
+ * to indicate failure; or -EINVAL if the function pointer is null.
+ */
+int pwrdm_for_each(int (*fn)(struct powerdomain *pwrdm, void *user),
+		   void *user)
+{
+	struct powerdomain *temp_pwrdm;
+	int ret = 0;
+
+	if (!fn)
+		return -EINVAL;
+
+	list_for_each_entry(temp_pwrdm, &pwrdm_list, node) {
+		ret = (*fn)(temp_pwrdm, user);
+		if (ret)
+			break;
+	}
+
+	return ret;
+}
+
+/**
+ * pwrdm_add_clkdm - add a clockdomain to a powerdomain
+ * @pwrdm: struct powerdomain * to add the clockdomain to
+ * @clkdm: struct clockdomain * to associate with a powerdomain
+ *
+ * Associate the clockdomain @clkdm with a powerdomain @pwrdm.  This
+ * enables the use of pwrdm_for_each_clkdm().  Returns -EINVAL if
+ * presented with invalid pointers; -ENOMEM if memory could not be allocated;
+ * or 0 upon success.
+ */
+int pwrdm_add_clkdm(struct powerdomain *pwrdm, struct clockdomain *clkdm)
+{
+	int i;
+	int ret = -EINVAL;
+
+	if (!pwrdm || !clkdm)
+		return -EINVAL;
+
+	pr_debug("powerdomain: associating clockdomain %s with powerdomain "
+		 "%s\n", clkdm->name, pwrdm->name);
+
+	for (i = 0; i < PWRDM_MAX_CLKDMS; i++) {
+		if (!pwrdm->pwrdm_clkdms[i])
+			break;
+#ifdef DEBUG
+		if (pwrdm->pwrdm_clkdms[i] == clkdm) {
+			ret = -EINVAL;
+			goto pac_exit;
+		}
+#endif
+	}
+
+	if (i == PWRDM_MAX_CLKDMS) {
+		pr_debug("powerdomain: increase PWRDM_MAX_CLKDMS for "
+			 "pwrdm %s clkdm %s\n", pwrdm->name, clkdm->name);
+		WARN_ON(1);
+		ret = -ENOMEM;
+		goto pac_exit;
+	}
+
+	pwrdm->pwrdm_clkdms[i] = clkdm;
+
+	ret = 0;
+
+pac_exit:
+	return ret;
+}
+
+/**
+ * pwrdm_del_clkdm - remove a clockdomain from a powerdomain
+ * @pwrdm: struct powerdomain * to add the clockdomain to
+ * @clkdm: struct clockdomain * to associate with a powerdomain
+ *
+ * Dissociate the clockdomain @clkdm from the powerdomain
+ * @pwrdm. Returns -EINVAL if presented with invalid pointers; -ENOENT
+ * if @clkdm was not associated with the powerdomain, or 0 upon
+ * success.
+ */
+int pwrdm_del_clkdm(struct powerdomain *pwrdm, struct clockdomain *clkdm)
+{
+	int ret = -EINVAL;
+	int i;
+
+	if (!pwrdm || !clkdm)
+		return -EINVAL;
+
+	pr_debug("powerdomain: dissociating clockdomain %s from powerdomain "
+		 "%s\n", clkdm->name, pwrdm->name);
+
+	for (i = 0; i < PWRDM_MAX_CLKDMS; i++)
+		if (pwrdm->pwrdm_clkdms[i] == clkdm)
+			break;
+
+	if (i == PWRDM_MAX_CLKDMS) {
+		pr_debug("powerdomain: clkdm %s not associated with pwrdm "
+			 "%s ?!\n", clkdm->name, pwrdm->name);
+		ret = -ENOENT;
+		goto pdc_exit;
+	}
+
+	pwrdm->pwrdm_clkdms[i] = NULL;
+
+	ret = 0;
+
+pdc_exit:
+	return ret;
+}
+
+/**
+ * pwrdm_for_each_clkdm - call function on each clkdm in a pwrdm
+ * @pwrdm: struct powerdomain * to iterate over
+ * @fn: callback function *
+ *
+ * Call the supplied function @fn for each clockdomain in the powerdomain
+ * @pwrdm.  The callback function can return anything but 0 to bail
+ * out early from the iterator.  Returns -EINVAL if presented with
+ * invalid pointers; or passes along the last return value of the
+ * callback function, which should be 0 for success or anything else
+ * to indicate failure.
+ */
+int pwrdm_for_each_clkdm(struct powerdomain *pwrdm,
+			 int (*fn)(struct powerdomain *pwrdm,
+				   struct clockdomain *clkdm))
+{
+	int ret = 0;
+	int i;
+
+	if (!fn)
+		return -EINVAL;
+
+	for (i = 0; i < PWRDM_MAX_CLKDMS && !ret; i++)
+		ret = (*fn)(pwrdm, pwrdm->pwrdm_clkdms[i]);
+
+	return ret;
+}
+
+/**
+ * pwrdm_get_mem_bank_count - get number of memory banks in this powerdomain
+ * @pwrdm: struct powerdomain *
+ *
+ * Return the number of controllable memory banks in powerdomain @pwrdm,
+ * starting with 1.  Returns -EINVAL if the powerdomain pointer is null.
+ */
+int pwrdm_get_mem_bank_count(struct powerdomain *pwrdm)
+{
+	if (!pwrdm)
+		return -EINVAL;
+
+	return pwrdm->banks;
+}
+
+/**
+ * pwrdm_set_next_pwrst - set next powerdomain power state
+ * @pwrdm: struct powerdomain * to set
+ * @pwrst: one of the PWRDM_POWER_* macros
+ *
+ * Set the powerdomain @pwrdm's next power state to @pwrst.  The powerdomain
+ * may not enter this state immediately if the preconditions for this state
+ * have not been satisfied.  Returns -EINVAL if the powerdomain pointer is
+ * null or if the power state is invalid for the powerdomin, or returns 0
+ * upon success.
+ */
+int pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return -EINVAL;
+
+	if (!(pwrdm->pwrsts & (1 << pwrst)))
+		return -EINVAL;
+
+	pr_debug("powerdomain: setting next powerstate for %s to %0x\n",
+		 pwrdm->name, pwrst);
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_set_next_pwrst) {
+		/* Trace the pwrdm desired target state */
+		trace_power_domain_target(pwrdm->name, pwrst,
+					  smp_processor_id());
+		/* Program the pwrdm desired target state */
+		ret = arch_pwrdm->pwrdm_set_next_pwrst(pwrdm, pwrst);
+	}
+
+	return ret;
+}
+
+/**
+ * pwrdm_read_next_pwrst - get next powerdomain power state
+ * @pwrdm: struct powerdomain * to get power state
+ *
+ * Return the powerdomain @pwrdm's next power state.  Returns -EINVAL
+ * if the powerdomain pointer is null or returns the next power state
+ * upon success.
+ */
+int pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return -EINVAL;
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_read_next_pwrst)
+		ret = arch_pwrdm->pwrdm_read_next_pwrst(pwrdm);
+
+	return ret;
+}
+
+/**
+ * pwrdm_read_pwrst - get current powerdomain power state
+ * @pwrdm: struct powerdomain * to get power state
+ *
+ * Return the powerdomain @pwrdm's current power state.	Returns -EINVAL
+ * if the powerdomain pointer is null or returns the current power state
+ * upon success.
+ */
+int pwrdm_read_pwrst(struct powerdomain *pwrdm)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return -EINVAL;
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_read_pwrst)
+		ret = arch_pwrdm->pwrdm_read_pwrst(pwrdm);
+
+	return ret;
+}
+
+/**
+ * pwrdm_read_prev_pwrst - get previous powerdomain power state
+ * @pwrdm: struct powerdomain * to get previous power state
+ *
+ * Return the powerdomain @pwrdm's previous power state.  Returns -EINVAL
+ * if the powerdomain pointer is null or returns the previous power state
+ * upon success.
+ */
+int pwrdm_read_prev_pwrst(struct powerdomain *pwrdm)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return -EINVAL;
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_read_prev_pwrst)
+		ret = arch_pwrdm->pwrdm_read_prev_pwrst(pwrdm);
+
+	return ret;
+}
+
+/**
+ * pwrdm_set_logic_retst - set powerdomain logic power state upon retention
+ * @pwrdm: struct powerdomain * to set
+ * @pwrst: one of the PWRDM_POWER_* macros
+ *
+ * Set the next power state @pwrst that the logic portion of the
+ * powerdomain @pwrdm will enter when the powerdomain enters retention.
+ * This will be either RETENTION or OFF, if supported.  Returns
+ * -EINVAL if the powerdomain pointer is null or the target power
+ * state is not not supported, or returns 0 upon success.
+ */
+int pwrdm_set_logic_retst(struct powerdomain *pwrdm, u8 pwrst)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return -EINVAL;
+
+	if (!(pwrdm->pwrsts_logic_ret & (1 << pwrst)))
+		return -EINVAL;
+
+	pr_debug("powerdomain: setting next logic powerstate for %s to %0x\n",
+		 pwrdm->name, pwrst);
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_set_logic_retst)
+		ret = arch_pwrdm->pwrdm_set_logic_retst(pwrdm, pwrst);
+
+	return ret;
+}
+
+/**
+ * pwrdm_set_mem_onst - set memory power state while powerdomain ON
+ * @pwrdm: struct powerdomain * to set
+ * @bank: memory bank number to set (0-3)
+ * @pwrst: one of the PWRDM_POWER_* macros
+ *
+ * Set the next power state @pwrst that memory bank @bank of the
+ * powerdomain @pwrdm will enter when the powerdomain enters the ON
+ * state.  @bank will be a number from 0 to 3, and represents different
+ * types of memory, depending on the powerdomain.  Returns -EINVAL if
+ * the powerdomain pointer is null or the target power state is not
+ * not supported for this memory bank, -EEXIST if the target memory
+ * bank does not exist or is not controllable, or returns 0 upon
+ * success.
+ */
+int pwrdm_set_mem_onst(struct powerdomain *pwrdm, u8 bank, u8 pwrst)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return -EINVAL;
+
+	if (pwrdm->banks < (bank + 1))
+		return -EEXIST;
+
+	if (!(pwrdm->pwrsts_mem_on[bank] & (1 << pwrst)))
+		return -EINVAL;
+
+	pr_debug("powerdomain: setting next memory powerstate for domain %s "
+		 "bank %0x while pwrdm-ON to %0x\n", pwrdm->name, bank, pwrst);
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_set_mem_onst)
+		ret = arch_pwrdm->pwrdm_set_mem_onst(pwrdm, bank, pwrst);
+
+	return ret;
+}
+
+/**
+ * pwrdm_set_mem_retst - set memory power state while powerdomain in RET
+ * @pwrdm: struct powerdomain * to set
+ * @bank: memory bank number to set (0-3)
+ * @pwrst: one of the PWRDM_POWER_* macros
+ *
+ * Set the next power state @pwrst that memory bank @bank of the
+ * powerdomain @pwrdm will enter when the powerdomain enters the
+ * RETENTION state.  Bank will be a number from 0 to 3, and represents
+ * different types of memory, depending on the powerdomain.  @pwrst
+ * will be either RETENTION or OFF, if supported.  Returns -EINVAL if
+ * the powerdomain pointer is null or the target power state is not
+ * not supported for this memory bank, -EEXIST if the target memory
+ * bank does not exist or is not controllable, or returns 0 upon
+ * success.
+ */
+int pwrdm_set_mem_retst(struct powerdomain *pwrdm, u8 bank, u8 pwrst)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return -EINVAL;
+
+	if (pwrdm->banks < (bank + 1))
+		return -EEXIST;
+
+	if (!(pwrdm->pwrsts_mem_ret[bank] & (1 << pwrst)))
+		return -EINVAL;
+
+	pr_debug("powerdomain: setting next memory powerstate for domain %s "
+		 "bank %0x while pwrdm-RET to %0x\n", pwrdm->name, bank, pwrst);
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_set_mem_retst)
+		ret = arch_pwrdm->pwrdm_set_mem_retst(pwrdm, bank, pwrst);
+
+	return ret;
+}
+
+/**
+ * pwrdm_read_logic_pwrst - get current powerdomain logic retention power state
+ * @pwrdm: struct powerdomain * to get current logic retention power state
+ *
+ * Return the power state that the logic portion of powerdomain @pwrdm
+ * will enter when the powerdomain enters retention.  Returns -EINVAL
+ * if the powerdomain pointer is null or returns the logic retention
+ * power state upon success.
+ */
+int pwrdm_read_logic_pwrst(struct powerdomain *pwrdm)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return -EINVAL;
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_read_logic_pwrst)
+		ret = arch_pwrdm->pwrdm_read_logic_pwrst(pwrdm);
+
+	return ret;
+}
+
+/**
+ * pwrdm_read_prev_logic_pwrst - get previous powerdomain logic power state
+ * @pwrdm: struct powerdomain * to get previous logic power state
+ *
+ * Return the powerdomain @pwrdm's previous logic power state.  Returns
+ * -EINVAL if the powerdomain pointer is null or returns the previous
+ * logic power state upon success.
+ */
+int pwrdm_read_prev_logic_pwrst(struct powerdomain *pwrdm)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return -EINVAL;
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_read_prev_logic_pwrst)
+		ret = arch_pwrdm->pwrdm_read_prev_logic_pwrst(pwrdm);
+
+	return ret;
+}
+
+/**
+ * pwrdm_read_logic_retst - get next powerdomain logic power state
+ * @pwrdm: struct powerdomain * to get next logic power state
+ *
+ * Return the powerdomain pwrdm's logic power state.  Returns -EINVAL
+ * if the powerdomain pointer is null or returns the next logic
+ * power state upon success.
+ */
+int pwrdm_read_logic_retst(struct powerdomain *pwrdm)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return -EINVAL;
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_read_logic_retst)
+		ret = arch_pwrdm->pwrdm_read_logic_retst(pwrdm);
+
+	return ret;
+}
+
+/**
+ * pwrdm_read_mem_pwrst - get current memory bank power state
+ * @pwrdm: struct powerdomain * to get current memory bank power state
+ * @bank: memory bank number (0-3)
+ *
+ * Return the powerdomain @pwrdm's current memory power state for bank
+ * @bank.  Returns -EINVAL if the powerdomain pointer is null, -EEXIST if
+ * the target memory bank does not exist or is not controllable, or
+ * returns the current memory power state upon success.
+ */
+int pwrdm_read_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return ret;
+
+	if (pwrdm->banks < (bank + 1))
+		return ret;
+
+	if (pwrdm->flags & PWRDM_HAS_MPU_QUIRK)
+		bank = 1;
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_read_mem_pwrst)
+		ret = arch_pwrdm->pwrdm_read_mem_pwrst(pwrdm, bank);
+
+	return ret;
+}
+
+/**
+ * pwrdm_read_prev_mem_pwrst - get previous memory bank power state
+ * @pwrdm: struct powerdomain * to get previous memory bank power state
+ * @bank: memory bank number (0-3)
+ *
+ * Return the powerdomain @pwrdm's previous memory power state for
+ * bank @bank.  Returns -EINVAL if the powerdomain pointer is null,
+ * -EEXIST if the target memory bank does not exist or is not
+ * controllable, or returns the previous memory power state upon
+ * success.
+ */
+int pwrdm_read_prev_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return ret;
+
+	if (pwrdm->banks < (bank + 1))
+		return ret;
+
+	if (pwrdm->flags & PWRDM_HAS_MPU_QUIRK)
+		bank = 1;
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_read_prev_mem_pwrst)
+		ret = arch_pwrdm->pwrdm_read_prev_mem_pwrst(pwrdm, bank);
+
+	return ret;
+}
+
+/**
+ * pwrdm_read_mem_retst - get next memory bank power state
+ * @pwrdm: struct powerdomain * to get mext memory bank power state
+ * @bank: memory bank number (0-3)
+ *
+ * Return the powerdomain pwrdm's next memory power state for bank
+ * x.  Returns -EINVAL if the powerdomain pointer is null, -EEXIST if
+ * the target memory bank does not exist or is not controllable, or
+ * returns the next memory power state upon success.
+ */
+int pwrdm_read_mem_retst(struct powerdomain *pwrdm, u8 bank)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return ret;
+
+	if (pwrdm->banks < (bank + 1))
+		return ret;
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_read_mem_retst)
+		ret = arch_pwrdm->pwrdm_read_mem_retst(pwrdm, bank);
+
+	return ret;
+}
+
+/**
+ * pwrdm_clear_all_prev_pwrst - clear previous powerstate register for a pwrdm
+ * @pwrdm: struct powerdomain * to clear
+ *
+ * Clear the powerdomain's previous power state register @pwrdm.
+ * Clears the entire register, including logic and memory bank
+ * previous power states.  Returns -EINVAL if the powerdomain pointer
+ * is null, or returns 0 upon success.
+ */
+int pwrdm_clear_all_prev_pwrst(struct powerdomain *pwrdm)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return ret;
+
+	/*
+	 * XXX should get the powerdomain's current state here;
+	 * warn & fail if it is not ON.
+	 */
+
+	pr_debug("powerdomain: clearing previous power state reg for %s\n",
+		 pwrdm->name);
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_clear_all_prev_pwrst)
+		ret = arch_pwrdm->pwrdm_clear_all_prev_pwrst(pwrdm);
+
+	return ret;
+}
+
+/**
+ * pwrdm_enable_hdwr_sar - enable automatic hardware SAR for a pwrdm
+ * @pwrdm: struct powerdomain *
+ *
+ * Enable automatic context save-and-restore upon power state change
+ * for some devices in the powerdomain @pwrdm.  Warning: this only
+ * affects a subset of devices in a powerdomain; check the TRM
+ * closely.  Returns -EINVAL if the powerdomain pointer is null or if
+ * the powerdomain does not support automatic save-and-restore, or
+ * returns 0 upon success.
+ */
+int pwrdm_enable_hdwr_sar(struct powerdomain *pwrdm)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return ret;
+
+	if (!(pwrdm->flags & PWRDM_HAS_HDWR_SAR))
+		return ret;
+
+	pr_debug("powerdomain: %s: setting SAVEANDRESTORE bit\n",
+		 pwrdm->name);
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_enable_hdwr_sar)
+		ret = arch_pwrdm->pwrdm_enable_hdwr_sar(pwrdm);
+
+	return ret;
+}
+
+/**
+ * pwrdm_disable_hdwr_sar - disable automatic hardware SAR for a pwrdm
+ * @pwrdm: struct powerdomain *
+ *
+ * Disable automatic context save-and-restore upon power state change
+ * for some devices in the powerdomain @pwrdm.  Warning: this only
+ * affects a subset of devices in a powerdomain; check the TRM
+ * closely.  Returns -EINVAL if the powerdomain pointer is null or if
+ * the powerdomain does not support automatic save-and-restore, or
+ * returns 0 upon success.
+ */
+int pwrdm_disable_hdwr_sar(struct powerdomain *pwrdm)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return ret;
+
+	if (!(pwrdm->flags & PWRDM_HAS_HDWR_SAR))
+		return ret;
+
+	pr_debug("powerdomain: %s: clearing SAVEANDRESTORE bit\n",
+		 pwrdm->name);
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_disable_hdwr_sar)
+		ret = arch_pwrdm->pwrdm_disable_hdwr_sar(pwrdm);
+
+	return ret;
+}
+
+/**
+ * pwrdm_has_hdwr_sar - test whether powerdomain supports hardware SAR
+ * @pwrdm: struct powerdomain *
+ *
+ * Returns 1 if powerdomain @pwrdm supports hardware save-and-restore
+ * for some devices, or 0 if it does not.
+ */
+bool pwrdm_has_hdwr_sar(struct powerdomain *pwrdm)
+{
+	return (pwrdm && pwrdm->flags & PWRDM_HAS_HDWR_SAR) ? 1 : 0;
+}
+
+/**
+ * pwrdm_set_lowpwrstchange - Request a low power state change
+ * @pwrdm: struct powerdomain *
+ *
+ * Allows a powerdomain to transtion to a lower power sleep state
+ * from an existing sleep state without waking up the powerdomain.
+ * Returns -EINVAL if the powerdomain pointer is null or if the
+ * powerdomain does not support LOWPOWERSTATECHANGE, or returns 0
+ * upon success.
+ */
+int pwrdm_set_lowpwrstchange(struct powerdomain *pwrdm)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return -EINVAL;
+
+	if (!(pwrdm->flags & PWRDM_HAS_LOWPOWERSTATECHANGE))
+		return -EINVAL;
+
+	pr_debug("powerdomain: %s: setting LOWPOWERSTATECHANGE bit\n",
+		 pwrdm->name);
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_set_lowpwrstchange)
+		ret = arch_pwrdm->pwrdm_set_lowpwrstchange(pwrdm);
+
+	return ret;
+}
+
+/**
+ * pwrdm_wait_transition - wait for powerdomain power transition to finish
+ * @pwrdm: struct powerdomain * to wait for
+ *
+ * If the powerdomain @pwrdm is in the process of a state transition,
+ * spin until it completes the power transition, or until an iteration
+ * bailout value is reached. Returns -EINVAL if the powerdomain
+ * pointer is null, -EAGAIN if the bailout value was reached, or
+ * returns 0 upon success.
+ */
+int pwrdm_wait_transition(struct powerdomain *pwrdm)
+{
+	int ret = -EINVAL;
+
+	if (!pwrdm)
+		return -EINVAL;
+
+	if (arch_pwrdm && arch_pwrdm->pwrdm_wait_transition)
+		ret = arch_pwrdm->pwrdm_wait_transition(pwrdm);
+
+	return ret;
+}
+
+int pwrdm_state_switch(struct powerdomain *pwrdm)
+{
+	return _pwrdm_state_switch(pwrdm, PWRDM_STATE_NOW);
+}
+
+int pwrdm_clkdm_state_switch(struct clockdomain *clkdm)
+{
+	if (clkdm != NULL && clkdm->pwrdm.ptr != NULL) {
+		pwrdm_wait_transition(clkdm->pwrdm.ptr);
+		return pwrdm_state_switch(clkdm->pwrdm.ptr);
+	}
+
+	return -EINVAL;
+}
+
+int pwrdm_pre_transition(void)
+{
+	pwrdm_for_each(_pwrdm_pre_transition_cb, NULL);
+	return 0;
+}
+
+int pwrdm_post_transition(void)
+{
+	pwrdm_for_each(_pwrdm_post_transition_cb, NULL);
+	return 0;
+}
+
+/**
+ * pwrdm_get_context_loss_count - get powerdomain's context loss count
+ * @pwrdm: struct powerdomain * to wait for
+ *
+ * Context loss count is the sum of powerdomain off-mode counter, the
+ * logic off counter and the per-bank memory off counter.  Returns 0
+ * (and WARNs) upon error, otherwise, returns the context loss count.
+ */
+u32 pwrdm_get_context_loss_count(struct powerdomain *pwrdm)
+{
+	int i, count;
+
+	if (!pwrdm) {
+		WARN(1, "powerdomain: %s: pwrdm is null\n", __func__);
+		return 0;
+	}
+
+	count = pwrdm->state_counter[PWRDM_POWER_OFF];
+	count += pwrdm->ret_logic_off_counter;
+
+	for (i = 0; i < pwrdm->banks; i++)
+		count += pwrdm->ret_mem_off_counter[i];
+
+	pr_debug("powerdomain: %s: context loss count = %u\n",
+		 pwrdm->name, count);
+
+	return count;
+}
+
+/**
+ * pwrdm_can_ever_lose_context - can this powerdomain ever lose context?
+ * @pwrdm: struct powerdomain *
+ *
+ * Given a struct powerdomain * @pwrdm, returns 1 if the powerdomain
+ * can lose either memory or logic context or if @pwrdm is invalid, or
+ * returns 0 otherwise.  This function is not concerned with how the
+ * powerdomain registers are programmed (i.e., to go off or not); it's
+ * concerned with whether it's ever possible for this powerdomain to
+ * go off while some other part of the chip is active.  This function
+ * assumes that every powerdomain can go to either ON or INACTIVE.
+ */
+bool pwrdm_can_ever_lose_context(struct powerdomain *pwrdm)
+{
+	int i;
+
+	if (IS_ERR_OR_NULL(pwrdm)) {
+		pr_debug("powerdomain: %s: invalid powerdomain pointer\n",
+			 __func__);
+		return 1;
+	}
+
+	if (pwrdm->pwrsts & PWRSTS_OFF)
+		return 1;
+
+	if (pwrdm->pwrsts & PWRSTS_RET) {
+		if (pwrdm->pwrsts_logic_ret & PWRSTS_OFF)
+			return 1;
+
+		for (i = 0; i < pwrdm->banks; i++)
+			if (pwrdm->pwrsts_mem_ret[i] & PWRSTS_OFF)
+				return 1;
+	}
+
+	for (i = 0; i < pwrdm->banks; i++)
+		if (pwrdm->pwrsts_mem_on[i] & PWRSTS_OFF)
+			return 1;
+
+	return 0;
+}