On 08/12/2014 09:43 PM, Lina Iyer wrote:
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@xxxxxxxxxxxxxx>
Signed-off-by: Mahesh Sivasubramanian <msivasub@xxxxxxxxxxxxxx>
Signed-off-by: Lina Iyer <lina.iyer@xxxxxxxxxx>
---
drivers/soc/qcom/Makefile | 2 +-
drivers/soc/qcom/msm-pm.c | 219 ++++++++++++++++++++++++++++++++++++++++++++++
include/soc/qcom/pm.h | 39 +++++++++
3 files changed, 259 insertions(+), 1 deletion(-)
create mode 100644 drivers/soc/qcom/msm-pm.c
create mode 100644 include/soc/qcom/pm.h
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index d7ae93b..7925f83 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -1,5 +1,5 @@
obj-$(CONFIG_QCOM_GSBI) += qcom_gsbi.o
-obj-$(CONFIG_QCOM_PM) += spm-devices.o spm.o
+obj-$(CONFIG_QCOM_PM) += spm-devices.o spm.o msm-pm.o
CFLAGS_scm.o :=$(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..f2f15b8
--- /dev/null
+++ b/drivers/soc/qcom/msm-pm.c
@@ -0,0 +1,219 @@
+/* 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/tick.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_CMD_CORE_HOTPLUGGED (0x10)
+#define SCM_FLUSH_FLAG_MASK (0x3)
+
+static bool msm_pm_is_L1_writeback(void)
+{
+ u32 cache_id = 0;
+
+#if defined(CONFIG_CPU_V7)
+ u32 sel = 0;
+
+ asm volatile ("mcr p15, 2, %[ccselr], c0, c0, 0\n\t"
+ "isb\n\t"
+ "mrc p15, 1, %[ccsidr], c0, c0, 0\n\t"
+ :[ccsidr]"=r" (cache_id)
+ :[ccselr]"r" (sel)
+ );
+ return cache_id & BIT(30);
+#elif defined(CONFIG_ARM64)
+ u32 sel = 0;
+ asm volatile("msr csselr_el1, %[ccselr]\n\t"
+ "isb\n\t"
+ "mrs %[ccsidr],ccsidr_el1\n\t"
+ :[ccsidr]"=r" (cache_id)
+ :[ccselr]"r" (sel)
+ );
+ return cache_id & BIT(30);
+#else
+#error No valid CPU arch selected
+#endif
+}
+
+static inline void msm_arch_idle(void)
+{
+ /* Flush and clock-gate */
+ mb();
Why is needed this memory barrier ?
+ wfi();
+}
+
+static bool msm_pm_swfi(bool from_idle)
+{
+ msm_arch_idle();
+ return true;
+}
+
+static bool msm_pm_retention(bool from_idle)
+{
+ int ret = 0;
+
+ ret = msm_spm_set_low_power_mode(MSM_SPM_MODE_RETENTION, false);
+ WARN_ON(ret);
+
+ msm_arch_idle();
+
+ ret = msm_spm_set_low_power_mode(MSM_SPM_MODE_CLOCK_GATING, false);
+ WARN_ON(ret);
Why do you need to set the clock gating mode each time you exit the
retention mode ?
+ return true;
+}
+
+static int msm_pm_collapse(unsigned long from_idle)
+{
+ enum msm_pm_l2_scm_flag flag = MSM_SCM_L2_ON;
+
+ /**
+ * Single core processors need to have L2
+ * flushed when powering down the core.
+ * Notify SCM to flush secure L2 lines.
+ */
+ if (num_possible_cpus() == 1)
+ flag = MSM_SCM_L2_OFF;
I am wondering if this shouldn't be handle by a mcpm driver.
Cc nico.
+ if (flag == MSM_SCM_L2_OFF)
+ flush_cache_all();
+ else if (msm_pm_is_L1_writeback())
+ flush_cache_louis();
+
+ flag &= SCM_FLUSH_FLAG_MASK;
+ if (!from_idle)
+ flag |= SCM_CMD_CORE_HOTPLUGGED;
+
+ 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 bool __ref msm_pm_spm_power_collapse(unsigned int cpu, bool from_idle)
+{
+ void *entry;
+ bool collapsed = 0;
+ int ret;
+ bool save_cpu_regs = (cpu_online(cpu) || from_idle);
+
+ if (from_idle)
+ cpu_pm_enter();
+
+ ret = msm_spm_set_low_power_mode(MSM_SPM_MODE_POWER_COLLAPSE, false);
+ WARN_ON(ret);
+
+ entry = save_cpu_regs ? cpu_resume : secondary_startup;
+ set_up_boot_address(entry, cpu);
+
+#ifdef CONFIG_CPU_V7
+ collapsed = !cpu_suspend(from_idle, msm_pm_collapse);
+#else
+ collapsed = !cpu_suspend(0);
+#endif
+
+ if (collapsed)
+ local_fiq_enable();
+
+ if (from_idle)
+ cpu_pm_exit();
+
+ ret = msm_spm_set_low_power_mode(MSM_SPM_MODE_CLOCK_GATING, false);
+ WARN_ON(ret);
+
+ return collapsed;
+}
+
+static bool msm_pm_power_collapse_standalone(bool from_idle)
+{
+ unsigned int cpu = smp_processor_id();
+ bool collapsed;
+
+ collapsed = msm_pm_spm_power_collapse(cpu, from_idle);
+
+ return collapsed;
+}
+
+static bool msm_pm_power_collapse(bool from_idle)
+{
+ unsigned int cpu = smp_processor_id();
+ bool collapsed;
+
+ collapsed = msm_pm_spm_power_collapse(cpu, from_idle);
+
+ return collapsed;
+}
+
+static bool (*execute[MSM_PM_SLEEP_MODE_NR])(bool idle) = {
+ [MSM_PM_SLEEP_MODE_WAIT_FOR_INTERRUPT] = msm_pm_swfi,
+ [MSM_PM_SLEEP_MODE_POWER_COLLAPSE_STANDALONE] =
+ msm_pm_power_collapse_standalone,
+ [MSM_PM_SLEEP_MODE_RETENTION] = msm_pm_retention,
+ [MSM_PM_SLEEP_MODE_POWER_COLLAPSE] = msm_pm_power_collapse,
+};
+
+/**
+ * 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.
+ *
+ */
+bool msm_cpu_pm_enter_sleep(enum msm_pm_sleep_mode mode, bool from_idle)
+{
+ bool exit_stat = false;
+
+ if (execute[mode])
+ exit_stat = execute[mode](from_idle);
+
+ local_irq_enable();
+ return exit_stat;
+}
+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..01872ad
--- /dev/null
+++ b/include/soc/qcom/pm.h
@@ -0,0 +1,39 @@
+/*
+ * 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_RETENTION,
+ MSM_PM_SLEEP_MODE_POWER_COLLAPSE_STANDALONE,
+ MSM_PM_SLEEP_MODE_POWER_COLLAPSE,
+ 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
+bool msm_cpu_pm_enter_sleep(enum msm_pm_sleep_mode mode, bool from_idle);
+#else
+static inline bool msm_cpu_pm_enter_sleep(enum msm_pm_sleep_mode mode,
+ bool from_idle)
+{ return true; }
+#endif
+
+#endif /* __QCOM_PM_H */
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