Initial import

1 files changed, 446 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/omap-mpuss-lowpower.c b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
new file mode 100644
index 000000000..79f49d904
--- /dev/null
+++ b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
@@ -0,0 +1,446 @@
+/*
+ * OMAP MPUSS low power code
+ *
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ *	Santosh Shilimkar <santosh.shilimkar@ti.com>
+ *
+ * OMAP4430 MPUSS mainly consists of dual Cortex-A9 with per-CPU
+ * Local timer and Watchdog, GIC, SCU, PL310 L2 cache controller,
+ * CPU0 and CPU1 LPRM modules.
+ * CPU0, CPU1 and MPUSS each have there own power domain and
+ * hence multiple low power combinations of MPUSS are possible.
+ *
+ * The CPU0 and CPU1 can't support Closed switch Retention (CSWR)
+ * because the mode is not supported by hw constraints of dormant
+ * mode. While waking up from the dormant mode, a reset  signal
+ * to the Cortex-A9 processor must be asserted by the external
+ * power controller.
+ *
+ * With architectural inputs and hardware recommendations, only
+ * below modes are supported from power gain vs latency point of view.
+ *
+ *	CPU0		CPU1		MPUSS
+ *	----------------------------------------------
+ *	ON		ON		ON
+ *	ON(Inactive)	OFF		ON(Inactive)
+ *	OFF		OFF		CSWR
+ *	OFF		OFF		OSWR
+ *	OFF		OFF		OFF(Device OFF *TBD)
+ *	----------------------------------------------
+ *
+ * Note: CPU0 is the master core and it is the last CPU to go down
+ * and first to wake-up when MPUSS low power states are excercised
+ *
+ *
+ * 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/kernel.h>
+#include <linux/io.h>
+#include <linux/errno.h>
+#include <linux/linkage.h>
+#include <linux/smp.h>
+
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+#include <asm/smp_scu.h>
+#include <asm/pgalloc.h>
+#include <asm/suspend.h>
+#include <asm/hardware/cache-l2x0.h>
+
+#include "soc.h"
+#include "common.h"
+#include "omap44xx.h"
+#include "omap4-sar-layout.h"
+#include "pm.h"
+#include "prcm_mpu44xx.h"
+#include "prcm_mpu54xx.h"
+#include "prminst44xx.h"
+#include "prcm44xx.h"
+#include "prm44xx.h"
+#include "prm-regbits-44xx.h"
+
+#ifdef CONFIG_SMP
+
+struct omap4_cpu_pm_info {
+	struct powerdomain *pwrdm;
+	void __iomem *scu_sar_addr;
+	void __iomem *wkup_sar_addr;
+	void __iomem *l2x0_sar_addr;
+};
+
+/**
+ * struct cpu_pm_ops - CPU pm operations
+ * @finish_suspend:	CPU suspend finisher function pointer
+ * @resume:		CPU resume function pointer
+ * @scu_prepare:	CPU Snoop Control program function pointer
+ * @hotplug_restart:	CPU restart function pointer
+ *
+ * Structure holds functions pointer for CPU low power operations like
+ * suspend, resume and scu programming.
+ */
+struct cpu_pm_ops {
+	int (*finish_suspend)(unsigned long cpu_state);
+	void (*resume)(void);
+	void (*scu_prepare)(unsigned int cpu_id, unsigned int cpu_state);
+	void (*hotplug_restart)(void);
+};
+
+static DEFINE_PER_CPU(struct omap4_cpu_pm_info, omap4_pm_info);
+static struct powerdomain *mpuss_pd;
+static void __iomem *sar_base;
+static u32 cpu_context_offset;
+
+static int default_finish_suspend(unsigned long cpu_state)
+{
+	omap_do_wfi();
+	return 0;
+}
+
+static void dummy_cpu_resume(void)
+{}
+
+static void dummy_scu_prepare(unsigned int cpu_id, unsigned int cpu_state)
+{}
+
+struct cpu_pm_ops omap_pm_ops = {
+	.finish_suspend		= default_finish_suspend,
+	.resume			= dummy_cpu_resume,
+	.scu_prepare		= dummy_scu_prepare,
+	.hotplug_restart	= dummy_cpu_resume,
+};
+
+/*
+ * Program the wakeup routine address for the CPU0 and CPU1
+ * used for OFF or DORMANT wakeup.
+ */
+static inline void set_cpu_wakeup_addr(unsigned int cpu_id, u32 addr)
+{
+	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
+
+	if (pm_info->wkup_sar_addr)
+		writel_relaxed(addr, pm_info->wkup_sar_addr);
+}
+
+/*
+ * Store the SCU power status value to scratchpad memory
+ */
+static void scu_pwrst_prepare(unsigned int cpu_id, unsigned int cpu_state)
+{
+	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
+	u32 scu_pwr_st;
+
+	switch (cpu_state) {
+	case PWRDM_POWER_RET:
+		scu_pwr_st = SCU_PM_DORMANT;
+		break;
+	case PWRDM_POWER_OFF:
+		scu_pwr_st = SCU_PM_POWEROFF;
+		break;
+	case PWRDM_POWER_ON:
+	case PWRDM_POWER_INACTIVE:
+	default:
+		scu_pwr_st = SCU_PM_NORMAL;
+		break;
+	}
+
+	if (pm_info->scu_sar_addr)
+		writel_relaxed(scu_pwr_st, pm_info->scu_sar_addr);
+}
+
+/* Helper functions for MPUSS OSWR */
+static inline void mpuss_clear_prev_logic_pwrst(void)
+{
+	u32 reg;
+
+	reg = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
+		OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET);
+	omap4_prminst_write_inst_reg(reg, OMAP4430_PRM_PARTITION,
+		OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET);
+}
+
+static inline void cpu_clear_prev_logic_pwrst(unsigned int cpu_id)
+{
+	u32 reg;
+
+	if (cpu_id) {
+		reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU1_INST,
+					cpu_context_offset);
+		omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU1_INST,
+					cpu_context_offset);
+	} else {
+		reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU0_INST,
+					cpu_context_offset);
+		omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU0_INST,
+					cpu_context_offset);
+	}
+}
+
+/*
+ * Store the CPU cluster state for L2X0 low power operations.
+ */
+static void l2x0_pwrst_prepare(unsigned int cpu_id, unsigned int save_state)
+{
+	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
+
+	if (pm_info->l2x0_sar_addr)
+		writel_relaxed(save_state, pm_info->l2x0_sar_addr);
+}
+
+/*
+ * Save the L2X0 AUXCTRL and POR value to SAR memory. Its used to
+ * in every restore MPUSS OFF path.
+ */
+#ifdef CONFIG_CACHE_L2X0
+static void __init save_l2x0_context(void)
+{
+	void __iomem *l2x0_base = omap4_get_l2cache_base();
+
+	if (l2x0_base && sar_base) {
+		writel_relaxed(l2x0_saved_regs.aux_ctrl,
+			       sar_base + L2X0_AUXCTRL_OFFSET);
+		writel_relaxed(l2x0_saved_regs.prefetch_ctrl,
+			       sar_base + L2X0_PREFETCH_CTRL_OFFSET);
+	}
+}
+#else
+static void __init save_l2x0_context(void)
+{}
+#endif
+
+/**
+ * omap4_enter_lowpower: OMAP4 MPUSS Low Power Entry Function
+ * The purpose of this function is to manage low power programming
+ * of OMAP4 MPUSS subsystem
+ * @cpu : CPU ID
+ * @power_state: Low power state.
+ *
+ * MPUSS states for the context save:
+ * save_state =
+ *	0 - Nothing lost and no need to save: MPUSS INACTIVE
+ *	1 - CPUx L1 and logic lost: MPUSS CSWR
+ *	2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR
+ *	3 - CPUx L1 and logic lost + GIC + L2 lost: DEVICE OFF
+ */
+int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
+{
+	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu);
+	unsigned int save_state = 0, cpu_logic_state = PWRDM_POWER_RET;
+	unsigned int wakeup_cpu;
+
+	if (omap_rev() == OMAP4430_REV_ES1_0)
+		return -ENXIO;
+
+	switch (power_state) {
+	case PWRDM_POWER_ON:
+	case PWRDM_POWER_INACTIVE:
+		save_state = 0;
+		break;
+	case PWRDM_POWER_OFF:
+		cpu_logic_state = PWRDM_POWER_OFF;
+		save_state = 1;
+		break;
+	case PWRDM_POWER_RET:
+		if (IS_PM44XX_ERRATUM(PM_OMAP4_CPU_OSWR_DISABLE)) {
+			save_state = 0;
+			break;
+		}
+	default:
+		/*
+		 * CPUx CSWR is invalid hardware state. Also CPUx OSWR
+		 * doesn't make much scense, since logic is lost and $L1
+		 * needs to be cleaned because of coherency. This makes
+		 * CPUx OSWR equivalent to CPUX OFF and hence not supported
+		 */
+		WARN_ON(1);
+		return -ENXIO;
+	}
+
+	pwrdm_pre_transition(NULL);
+
+	/*
+	 * Check MPUSS next state and save interrupt controller if needed.
+	 * In MPUSS OSWR or device OFF, interrupt controller  contest is lost.
+	 */
+	mpuss_clear_prev_logic_pwrst();
+	if ((pwrdm_read_next_pwrst(mpuss_pd) == PWRDM_POWER_RET) &&
+		(pwrdm_read_logic_retst(mpuss_pd) == PWRDM_POWER_OFF))
+		save_state = 2;
+
+	cpu_clear_prev_logic_pwrst(cpu);
+	pwrdm_set_next_pwrst(pm_info->pwrdm, power_state);
+	pwrdm_set_logic_retst(pm_info->pwrdm, cpu_logic_state);
+	set_cpu_wakeup_addr(cpu, virt_to_phys(omap_pm_ops.resume));
+	omap_pm_ops.scu_prepare(cpu, power_state);
+	l2x0_pwrst_prepare(cpu, save_state);
+
+	/*
+	 * Call low level function  with targeted low power state.
+	 */
+	if (save_state)
+		cpu_suspend(save_state, omap_pm_ops.finish_suspend);
+	else
+		omap_pm_ops.finish_suspend(save_state);
+
+	if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD) && cpu)
+		gic_dist_enable();
+
+	/*
+	 * Restore the CPUx power state to ON otherwise CPUx
+	 * power domain can transitions to programmed low power
+	 * state while doing WFI outside the low powe code. On
+	 * secure devices, CPUx does WFI which can result in
+	 * domain transition
+	 */
+	wakeup_cpu = smp_processor_id();
+	pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
+
+	pwrdm_post_transition(NULL);
+
+	return 0;
+}
+
+/**
+ * omap4_hotplug_cpu: OMAP4 CPU hotplug entry
+ * @cpu : CPU ID
+ * @power_state: CPU low power state.
+ */
+int omap4_hotplug_cpu(unsigned int cpu, unsigned int power_state)
+{
+	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu);
+	unsigned int cpu_state = 0;
+
+	if (omap_rev() == OMAP4430_REV_ES1_0)
+		return -ENXIO;
+
+	/* Use the achievable power state for the domain */
+	power_state = pwrdm_get_valid_lp_state(pm_info->pwrdm,
+					       false, power_state);
+
+	if (power_state == PWRDM_POWER_OFF)
+		cpu_state = 1;
+
+	pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
+	pwrdm_set_next_pwrst(pm_info->pwrdm, power_state);
+	set_cpu_wakeup_addr(cpu, virt_to_phys(omap_pm_ops.hotplug_restart));
+	omap_pm_ops.scu_prepare(cpu, power_state);
+
+	/*
+	 * CPU never retuns back if targeted power state is OFF mode.
+	 * CPU ONLINE follows normal CPU ONLINE ptah via
+	 * omap4_secondary_startup().
+	 */
+	omap_pm_ops.finish_suspend(cpu_state);
+
+	pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
+	return 0;
+}
+
+
+/*
+ * Enable Mercury Fast HG retention mode by default.
+ */
+static void enable_mercury_retention_mode(void)
+{
+	u32 reg;
+
+	reg = omap4_prcm_mpu_read_inst_reg(OMAP54XX_PRCM_MPU_DEVICE_INST,
+				  OMAP54XX_PRCM_MPU_PRM_PSCON_COUNT_OFFSET);
+	/* Enable HG_EN, HG_RAMPUP = fast mode */
+	reg |= BIT(24) | BIT(25);
+	omap4_prcm_mpu_write_inst_reg(reg, OMAP54XX_PRCM_MPU_DEVICE_INST,
+				      OMAP54XX_PRCM_MPU_PRM_PSCON_COUNT_OFFSET);
+}
+
+/*
+ * Initialise OMAP4 MPUSS
+ */
+int __init omap4_mpuss_init(void)
+{
+	struct omap4_cpu_pm_info *pm_info;
+
+	if (omap_rev() == OMAP4430_REV_ES1_0) {
+		WARN(1, "Power Management not supported on OMAP4430 ES1.0\n");
+		return -ENODEV;
+	}
+
+	if (cpu_is_omap44xx())
+		sar_base = omap4_get_sar_ram_base();
+
+	/* Initilaise per CPU PM information */
+	pm_info = &per_cpu(omap4_pm_info, 0x0);
+	if (sar_base) {
+		pm_info->scu_sar_addr = sar_base + SCU_OFFSET0;
+		pm_info->wkup_sar_addr = sar_base +
+					CPU0_WAKEUP_NS_PA_ADDR_OFFSET;
+		pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET0;
+	}
+	pm_info->pwrdm = pwrdm_lookup("cpu0_pwrdm");
+	if (!pm_info->pwrdm) {
+		pr_err("Lookup failed for CPU0 pwrdm\n");
+		return -ENODEV;
+	}
+
+	/* Clear CPU previous power domain state */
+	pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
+	cpu_clear_prev_logic_pwrst(0);
+
+	/* Initialise CPU0 power domain state to ON */
+	pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
+
+	pm_info = &per_cpu(omap4_pm_info, 0x1);
+	if (sar_base) {
+		pm_info->scu_sar_addr = sar_base + SCU_OFFSET1;
+		pm_info->wkup_sar_addr = sar_base +
+					CPU1_WAKEUP_NS_PA_ADDR_OFFSET;
+		pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET1;
+	}
+
+	pm_info->pwrdm = pwrdm_lookup("cpu1_pwrdm");
+	if (!pm_info->pwrdm) {
+		pr_err("Lookup failed for CPU1 pwrdm\n");
+		return -ENODEV;
+	}
+
+	/* Clear CPU previous power domain state */
+	pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
+	cpu_clear_prev_logic_pwrst(1);
+
+	/* Initialise CPU1 power domain state to ON */
+	pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
+
+	mpuss_pd = pwrdm_lookup("mpu_pwrdm");
+	if (!mpuss_pd) {
+		pr_err("Failed to lookup MPUSS power domain\n");
+		return -ENODEV;
+	}
+	pwrdm_clear_all_prev_pwrst(mpuss_pd);
+	mpuss_clear_prev_logic_pwrst();
+
+	if (sar_base) {
+		/* Save device type on scratchpad for low level code to use */
+		writel_relaxed((omap_type() != OMAP2_DEVICE_TYPE_GP) ? 1 : 0,
+			       sar_base + OMAP_TYPE_OFFSET);
+		save_l2x0_context();
+	}
+
+	if (cpu_is_omap44xx()) {
+		omap_pm_ops.finish_suspend = omap4_finish_suspend;
+		omap_pm_ops.resume = omap4_cpu_resume;
+		omap_pm_ops.scu_prepare = scu_pwrst_prepare;
+		omap_pm_ops.hotplug_restart = omap4_secondary_startup;
+		cpu_context_offset = OMAP4_RM_CPU0_CPU0_CONTEXT_OFFSET;
+	} else if (soc_is_omap54xx() || soc_is_dra7xx()) {
+		cpu_context_offset = OMAP54XX_RM_CPU0_CPU0_CONTEXT_OFFSET;
+		enable_mercury_retention_mode();
+	}
+
+	if (cpu_is_omap446x())
+		omap_pm_ops.hotplug_restart = omap4460_secondary_startup;
+
+	return 0;
+}
+
+#endif