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-rw-r--r--kernel/arch/arm/mach-omap2/pm44xx.c295
1 files changed, 295 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-omap2/pm44xx.c b/kernel/arch/arm/mach-omap2/pm44xx.c
new file mode 100644
index 000000000..d697cecf7
--- /dev/null
+++ b/kernel/arch/arm/mach-omap2/pm44xx.c
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+/*
+ * OMAP4+ Power Management Routines
+ *
+ * Copyright (C) 2010-2013 Texas Instruments, Inc.
+ * Rajendra Nayak <rnayak@ti.com>
+ * Santosh Shilimkar <santosh.shilimkar@ti.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.
+ */
+
+#include <linux/pm.h>
+#include <linux/suspend.h>
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <asm/system_misc.h>
+
+#include "soc.h"
+#include "common.h"
+#include "clockdomain.h"
+#include "powerdomain.h"
+#include "pm.h"
+
+u16 pm44xx_errata;
+
+struct power_state {
+ struct powerdomain *pwrdm;
+ u32 next_state;
+ u32 next_logic_state;
+#ifdef CONFIG_SUSPEND
+ u32 saved_state;
+ u32 saved_logic_state;
+#endif
+ struct list_head node;
+};
+
+/**
+ * struct static_dep_map - Static dependency map
+ * @from: from clockdomain
+ * @to: to clockdomain
+ */
+struct static_dep_map {
+ const char *from;
+ const char *to;
+};
+
+static u32 cpu_suspend_state = PWRDM_POWER_OFF;
+
+static LIST_HEAD(pwrst_list);
+
+#ifdef CONFIG_SUSPEND
+static int omap4_pm_suspend(void)
+{
+ struct power_state *pwrst;
+ int state, ret = 0;
+ u32 cpu_id = smp_processor_id();
+
+ /* Save current powerdomain state */
+ list_for_each_entry(pwrst, &pwrst_list, node) {
+ pwrst->saved_state = pwrdm_read_next_pwrst(pwrst->pwrdm);
+ pwrst->saved_logic_state = pwrdm_read_logic_retst(pwrst->pwrdm);
+ }
+
+ /* Set targeted power domain states by suspend */
+ list_for_each_entry(pwrst, &pwrst_list, node) {
+ omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
+ pwrdm_set_logic_retst(pwrst->pwrdm, pwrst->next_logic_state);
+ }
+
+ /*
+ * For MPUSS to hit power domain retention(CSWR or OSWR),
+ * CPU0 and CPU1 power domains need to be in OFF or DORMANT state,
+ * since CPU power domain CSWR is not supported by hardware
+ * Only master CPU follows suspend path. All other CPUs follow
+ * CPU hotplug path in system wide suspend. On OMAP4, CPU power
+ * domain CSWR is not supported by hardware.
+ * More details can be found in OMAP4430 TRM section 4.3.4.2.
+ */
+ omap4_enter_lowpower(cpu_id, cpu_suspend_state);
+
+ /* Restore next powerdomain state */
+ list_for_each_entry(pwrst, &pwrst_list, node) {
+ state = pwrdm_read_prev_pwrst(pwrst->pwrdm);
+ if (state > pwrst->next_state) {
+ pr_info("Powerdomain (%s) didn't enter target state %d\n",
+ pwrst->pwrdm->name, pwrst->next_state);
+ ret = -1;
+ }
+ omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state);
+ pwrdm_set_logic_retst(pwrst->pwrdm, pwrst->saved_logic_state);
+ }
+ if (ret) {
+ pr_crit("Could not enter target state in pm_suspend\n");
+ /*
+ * OMAP4 chip PM currently works only with certain (newer)
+ * versions of bootloaders. This is due to missing code in the
+ * kernel to properly reset and initialize some devices.
+ * Warn the user about the bootloader version being one of the
+ * possible causes.
+ * http://www.spinics.net/lists/arm-kernel/msg218641.html
+ */
+ pr_warn("A possible cause could be an old bootloader - try u-boot >= v2012.07\n");
+ } else {
+ pr_info("Successfully put all powerdomains to target state\n");
+ }
+
+ return 0;
+}
+#else
+#define omap4_pm_suspend NULL
+#endif /* CONFIG_SUSPEND */
+
+static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
+{
+ struct power_state *pwrst;
+
+ if (!pwrdm->pwrsts)
+ return 0;
+
+ /*
+ * Skip CPU0 and CPU1 power domains. CPU1 is programmed
+ * through hotplug path and CPU0 explicitly programmed
+ * further down in the code path
+ */
+ if (!strncmp(pwrdm->name, "cpu", 3)) {
+ if (IS_PM44XX_ERRATUM(PM_OMAP4_CPU_OSWR_DISABLE))
+ cpu_suspend_state = PWRDM_POWER_RET;
+ return 0;
+ }
+
+ pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
+ if (!pwrst)
+ return -ENOMEM;
+
+ pwrst->pwrdm = pwrdm;
+ pwrst->next_state = pwrdm_get_valid_lp_state(pwrdm, false,
+ PWRDM_POWER_RET);
+ pwrst->next_logic_state = pwrdm_get_valid_lp_state(pwrdm, true,
+ PWRDM_POWER_OFF);
+
+ list_add(&pwrst->node, &pwrst_list);
+
+ return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
+}
+
+/**
+ * omap_default_idle - OMAP4 default ilde routine.'
+ *
+ * Implements OMAP4 memory, IO ordering requirements which can't be addressed
+ * with default cpu_do_idle() hook. Used by all CPUs with !CONFIG_CPU_IDLE and
+ * by secondary CPU with CONFIG_CPU_IDLE.
+ */
+static void omap_default_idle(void)
+{
+ omap_do_wfi();
+}
+
+/*
+ * The dynamic dependency between MPUSS -> MEMIF and
+ * MPUSS -> L4_PER/L3_* and DUCATI -> L3_* doesn't work as
+ * expected. The hardware recommendation is to enable static
+ * dependencies for these to avoid system lock ups or random crashes.
+ * The L4 wakeup depedency is added to workaround the OCP sync hardware
+ * BUG with 32K synctimer which lead to incorrect timer value read
+ * from the 32K counter. The BUG applies for GPTIMER1 and WDT2 which
+ * are part of L4 wakeup clockdomain.
+ */
+static const struct static_dep_map omap4_static_dep_map[] = {
+ {.from = "mpuss_clkdm", .to = "l3_emif_clkdm"},
+ {.from = "mpuss_clkdm", .to = "l3_1_clkdm"},
+ {.from = "mpuss_clkdm", .to = "l3_2_clkdm"},
+ {.from = "ducati_clkdm", .to = "l3_1_clkdm"},
+ {.from = "ducati_clkdm", .to = "l3_2_clkdm"},
+ {.from = NULL} /* TERMINATION */
+};
+
+static const struct static_dep_map omap5_dra7_static_dep_map[] = {
+ {.from = "mpu_clkdm", .to = "emif_clkdm"},
+ {.from = NULL} /* TERMINATION */
+};
+
+/**
+ * omap4plus_init_static_deps() - Initialize a static dependency map
+ * @map: Mapping of clock domains
+ */
+static inline int omap4plus_init_static_deps(const struct static_dep_map *map)
+{
+ int ret;
+ struct clockdomain *from, *to;
+
+ if (!map)
+ return 0;
+
+ while (map->from) {
+ from = clkdm_lookup(map->from);
+ to = clkdm_lookup(map->to);
+ if (!from || !to) {
+ pr_err("Failed lookup %s or %s for wakeup dependency\n",
+ map->from, map->to);
+ return -EINVAL;
+ }
+ ret = clkdm_add_wkdep(from, to);
+ if (ret) {
+ pr_err("Failed to add %s -> %s wakeup dependency(%d)\n",
+ map->from, map->to, ret);
+ return ret;
+ }
+
+ map++;
+ };
+
+ return 0;
+}
+
+/**
+ * omap4_pm_init_early - Does early initialization necessary for OMAP4+ devices
+ *
+ * Initializes basic stuff for power management functionality.
+ */
+int __init omap4_pm_init_early(void)
+{
+ if (cpu_is_omap446x())
+ pm44xx_errata |= PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD;
+
+ if (soc_is_omap54xx() || soc_is_dra7xx())
+ pm44xx_errata |= PM_OMAP4_CPU_OSWR_DISABLE;
+
+ return 0;
+}
+
+/**
+ * omap4_pm_init - Init routine for OMAP4+ devices
+ *
+ * Initializes all powerdomain and clockdomain target states
+ * and all PRCM settings.
+ * Return: Returns the error code returned by called functions.
+ */
+int __init omap4_pm_init(void)
+{
+ int ret = 0;
+
+ if (omap_rev() == OMAP4430_REV_ES1_0) {
+ WARN(1, "Power Management not supported on OMAP4430 ES1.0\n");
+ return -ENODEV;
+ }
+
+ pr_info("Power Management for TI OMAP4+ devices.\n");
+
+ /*
+ * OMAP4 chip PM currently works only with certain (newer)
+ * versions of bootloaders. This is due to missing code in the
+ * kernel to properly reset and initialize some devices.
+ * http://www.spinics.net/lists/arm-kernel/msg218641.html
+ */
+ if (cpu_is_omap44xx())
+ pr_warn("OMAP4 PM: u-boot >= v2012.07 is required for full PM support\n");
+
+ ret = pwrdm_for_each(pwrdms_setup, NULL);
+ if (ret) {
+ pr_err("Failed to setup powerdomains.\n");
+ goto err2;
+ }
+
+ if (cpu_is_omap44xx())
+ ret = omap4plus_init_static_deps(omap4_static_dep_map);
+ else if (soc_is_omap54xx() || soc_is_dra7xx())
+ ret = omap4plus_init_static_deps(omap5_dra7_static_dep_map);
+
+ if (ret) {
+ pr_err("Failed to initialise static dependencies.\n");
+ goto err2;
+ }
+
+ ret = omap4_mpuss_init();
+ if (ret) {
+ pr_err("Failed to initialise OMAP4 MPUSS\n");
+ goto err2;
+ }
+
+ (void) clkdm_for_each(omap_pm_clkdms_setup, NULL);
+
+ omap_common_suspend_init(omap4_pm_suspend);
+
+ /* Overwrite the default cpu_do_idle() */
+ arm_pm_idle = omap_default_idle;
+
+ if (cpu_is_omap44xx())
+ omap4_idle_init();
+
+err2:
+ return ret;
+}