[v4,6/8] qcom: msm-pm: Add cpu low power mode functions

Message ID 1408486537-6358-7-git-send-email-lina.iyer@linaro.org
State New
Headers show

Commit Message

Lina Iyer Aug. 19, 2014, 10:15 p.m.
Add interface layer to abstract and handle hardware specific
functionality for executing various cpu low power modes in QCOM
chipsets.

Signed-off-by: Venkat Devarasetty <vdevaras@codeaurora.org>
Signed-off-by: Mahesh Sivasubramanian <msivasub@codeaurora.org>
Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
---
 drivers/soc/qcom/Makefile |   2 +-
 drivers/soc/qcom/msm-pm.c | 117 ++++++++++++++++++++++++++++++++++++++++++++++
 include/soc/qcom/pm.h     |  38 +++++++++++++++
 3 files changed, 156 insertions(+), 1 deletion(-)
 create mode 100644 drivers/soc/qcom/msm-pm.c
 create mode 100644 include/soc/qcom/pm.h

Patch

diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index 9457b2a..acdd6fa 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -1,4 +1,4 @@ 
 obj-$(CONFIG_QCOM_GSBI)	+=	qcom_gsbi.o
-obj-$(CONFIG_QCOM_PM)	+=	spm.o spm-devices.o
+obj-$(CONFIG_QCOM_PM)	+=	spm.o spm-devices.o msm-pm.o
 CFLAGS_scm.o :=$(call as-instr,.arch_extension sec,-DREQUIRES_SEC=1)
 obj-$(CONFIG_QCOM_SCM) += scm.o scm-boot.o
diff --git a/drivers/soc/qcom/msm-pm.c b/drivers/soc/qcom/msm-pm.c
new file mode 100644
index 0000000..5a984e3
--- /dev/null
+++ b/drivers/soc/qcom/msm-pm.c
@@ -0,0 +1,117 @@ 
+/* Copyright (c) 2010-2014, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/smp.h>
+#include <linux/platform_device.h>
+#include <linux/cpu_pm.h>
+#include <linux/uaccess.h>
+
+#include <soc/qcom/spm.h>
+#include <soc/qcom/pm.h>
+#include <soc/qcom/scm.h>
+#include <soc/qcom/scm-boot.h>
+
+#include <asm/suspend.h>
+#include <asm/cacheflush.h>
+#include <asm/cputype.h>
+#include <asm/system_misc.h>
+
+#define SCM_CMD_TERMINATE_PC	(0x2)
+#define SCM_FLUSH_FLAG_MASK	(0x3)
+
+static int msm_pm_collapse(unsigned long unused)
+{
+	enum msm_pm_l2_scm_flag flag;
+
+	flag = MSM_SCM_L2_ON & SCM_FLUSH_FLAG_MASK;
+	scm_call_atomic1(SCM_SVC_BOOT, SCM_CMD_TERMINATE_PC, flag);
+
+	return 0;
+}
+
+static void set_up_boot_address(void *entry, int cpu)
+{
+	static int flags[NR_CPUS] = {
+		SCM_FLAG_WARMBOOT_CPU0,
+		SCM_FLAG_WARMBOOT_CPU1,
+		SCM_FLAG_WARMBOOT_CPU2,
+		SCM_FLAG_WARMBOOT_CPU3,
+	};
+	static DEFINE_PER_CPU(void *, last_known_entry);
+
+	if (entry == per_cpu(last_known_entry, cpu))
+		return;
+
+	per_cpu(last_known_entry, cpu) = entry;
+	scm_set_boot_addr(virt_to_phys(entry), flags[cpu]);
+}
+
+static int do_power_down(void)
+{
+	int ret;
+
+	cpu_pm_enter();
+
+	msm_spm_set_low_power_mode(MSM_SPM_MODE_POWER_COLLAPSE);
+	set_up_boot_address(cpu_resume, raw_smp_processor_id());
+	ret = cpu_suspend(0, msm_pm_collapse);
+
+	cpu_pm_exit();
+
+	return ret;
+}
+
+static inline int do_idle(void)
+{
+	msm_spm_set_low_power_mode(MSM_SPM_MODE_CLOCK_GATING);
+
+	/* Flush and clock-gate */
+	mb();
+	wfi();
+
+	return 0;
+}
+
+/**
+ * msm_cpu_pm_enter_sleep(): Enter a low power mode on current cpu
+ *
+ * @mode - sleep mode to enter
+ * @from_idle - bool to indicate that the mode is exercised during idle/suspend
+ *
+ * The code should be with interrupts disabled and on the core on which the
+ * low power is to be executed.
+ *
+ */
+int msm_cpu_pm_enter_sleep(enum msm_pm_sleep_mode mode, bool from_idle)
+{
+	int ret;
+
+	switch (mode) {
+	case MSM_PM_SLEEP_MODE_POWER_COLLAPSE_STANDALONE:
+		ret = do_power_down();
+		break;
+	default:
+	case MSM_PM_SLEEP_MODE_WAIT_FOR_INTERRUPT:
+		ret = do_idle();
+		break;
+	}
+
+	local_irq_enable();
+
+	return ret;
+}
+EXPORT_SYMBOL(msm_cpu_pm_enter_sleep);
diff --git a/include/soc/qcom/pm.h b/include/soc/qcom/pm.h
new file mode 100644
index 0000000..7563e09
--- /dev/null
+++ b/include/soc/qcom/pm.h
@@ -0,0 +1,38 @@ 
+/*
+ * Copyright (c) 2009-2014, The Linux Foundation. All rights reserved.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef __QCOM_PM_H
+#define __QCOM_PM_H
+
+enum msm_pm_sleep_mode {
+	MSM_PM_SLEEP_MODE_WAIT_FOR_INTERRUPT,
+	MSM_PM_SLEEP_MODE_POWER_COLLAPSE_STANDALONE,
+	MSM_PM_SLEEP_MODE_NR,
+};
+
+
+enum msm_pm_l2_scm_flag {
+	MSM_SCM_L2_ON = 0,
+	MSM_SCM_L2_OFF = 1
+};
+
+#ifdef CONFIG_QCOM_PM
+int msm_cpu_pm_enter_sleep(enum msm_pm_sleep_mode mode, bool from_idle);
+#else
+static inline int msm_cpu_pm_enter_sleep(enum msm_pm_sleep_mode mode,
+						bool from_idle)
+{ return -ENODEV; }
+#endif
+
+#endif  /* __QCOM_PM_H */