/* Copyright (c) 2011-2013, 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/delay.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <mach/msm_iomap.h>
#include <mach/socinfo.h>
#include "spm.h"
#include "spm_driver.h"

struct msm_spm_power_modes {
	uint32_t mode;
	bool notify_rpm;
	uint32_t start_addr;

};

struct msm_spm_device {
	bool initialized;
	struct msm_spm_driver_data reg_data;
	struct msm_spm_power_modes *modes;
	uint32_t num_modes;
	uint32_t cpu_vdd;
};

struct msm_spm_vdd_info {
	uint32_t cpu;
	uint32_t vlevel;
	int err;
};

static struct msm_spm_device msm_spm_l2_device;
static DEFINE_PER_CPU_SHARED_ALIGNED(struct msm_spm_device, msm_cpu_spm_device);


static void msm_spm_smp_set_vdd(void *data)
{
	struct msm_spm_device *dev;
	struct msm_spm_vdd_info *info = (struct msm_spm_vdd_info *)data;

	dev = &per_cpu(msm_cpu_spm_device, info->cpu);
	if (!dev->initialized)
		return;
	dev->cpu_vdd = info->vlevel;
	info->err = msm_spm_drv_set_vdd(&dev->reg_data, info->vlevel);
}

/**
 * msm_spm_set_vdd(): Set core voltage
 * @cpu: core id
 * @vlevel: Encoded PMIC data.
 */
int msm_spm_set_vdd(unsigned int cpu, unsigned int vlevel)
{
	struct msm_spm_vdd_info info;
	int ret;

	info.cpu = cpu;
	info.vlevel = vlevel;
	info.err = -ENODEV;

	if ((smp_processor_id() != cpu) && cpu_online(cpu)) {
		/**
		 * We do not want to set the voltage of another core from
		 * this core, as its possible that we may race the vdd change
		 * with the SPM state machine of that core, which could also
		 * be changing the voltage of that core during power collapse.
		 * Hence, set the function to be executed on that core and block
		 * until the vdd change is complete.
		 */
		ret = smp_call_function_single(cpu, msm_spm_smp_set_vdd,
				&info, true);
		if (!ret)
			ret = info.err;
	} else {
		/**
		 * Since the core is not online, it is safe to set the vdd
		 * directly.
		 */
		msm_spm_smp_set_vdd(&info);
		ret = info.err;
	}

	return ret;
}
EXPORT_SYMBOL(msm_spm_set_vdd);

/**
 * msm_spm_get_vdd(): Get core voltage
 * @cpu: core id
 * @return: Returns encoded PMIC data.
 */
unsigned int msm_spm_get_vdd(unsigned int cpu)
{
	struct msm_spm_device *dev;

	dev = &per_cpu(msm_cpu_spm_device, cpu);
	return dev->cpu_vdd;
}
EXPORT_SYMBOL(msm_spm_get_vdd);

static int msm_spm_dev_set_low_power_mode(struct msm_spm_device *dev,
		unsigned int mode, bool notify_rpm)
{
	uint32_t i;
	uint32_t start_addr = 0;
	int ret = -EINVAL;

	if (!dev->initialized)
		return -ENXIO;

	if (mode == MSM_SPM_MODE_DISABLED) {
		ret = msm_spm_drv_set_spm_enable(&dev->reg_data, false);
	} else if (!msm_spm_drv_set_spm_enable(&dev->reg_data, true)) {
		for (i = 0; i < dev->num_modes; i++) {
			if ((dev->modes[i].mode == mode) &&
				(dev->modes[i].notify_rpm == notify_rpm)) {
				start_addr = dev->modes[i].start_addr;
				break;
			}
		}
		ret = msm_spm_drv_set_low_power_mode(&dev->reg_data,
					start_addr);
	}
	return ret;
}

static int __devinit msm_spm_dev_init(struct msm_spm_device *dev,
		struct msm_spm_platform_data *data)
{
	int i, ret = -ENOMEM;
	uint32_t offset = 0;

	dev->num_modes = data->num_modes;
	dev->modes = kmalloc(
			sizeof(struct msm_spm_power_modes) * dev->num_modes,
			GFP_KERNEL);

	if (!dev->modes)
		goto spm_failed_malloc;

	dev->reg_data.ver_reg = data->ver_reg;
	ret = msm_spm_drv_init(&dev->reg_data, data);

	if (ret)
		goto spm_failed_init;

	for (i = 0; i < dev->num_modes; i++) {

		/* Default offset is 0 and gets updated as we write more
		 * sequences into SPM
		 */
		dev->modes[i].start_addr = offset;
		ret = msm_spm_drv_write_seq_data(&dev->reg_data,
						data->modes[i].cmd, &offset);
		if (ret < 0)
			goto spm_failed_init;

		dev->modes[i].mode = data->modes[i].mode;
		dev->modes[i].notify_rpm = data->modes[i].notify_rpm;
	}
	msm_spm_drv_flush_seq_entry(&dev->reg_data);
	dev->initialized = true;
	return 0;

spm_failed_init:
	kfree(dev->modes);
spm_failed_malloc:
	return ret;
}

/**
 * msm_spm_turn_on_cpu_rail(): Power on cpu rail before turning on core
 * @cpu: core id
 */
int msm_spm_turn_on_cpu_rail(unsigned int cpu)
{
	uint32_t val = 0;
	uint32_t timeout = 0;
	void *reg = NULL;
	void *saw_bases[] = {
		0,
		MSM_SAW1_BASE,
		MSM_SAW2_BASE,
		MSM_SAW3_BASE
	};

	if (cpu == 0 || cpu >= num_possible_cpus())
		return -EINVAL;

	reg = saw_bases[cpu];

	if (soc_class_is_msm8960() || soc_class_is_msm8930() ||
	    soc_class_is_apq8064()) {
		val = 0xA4;
		reg += 0x14;
		timeout = 512;
	} else {
		return -ENOSYS;
	}

	writel_relaxed(val, reg);
	mb();
	udelay(timeout);

	return 0;
}
EXPORT_SYMBOL(msm_spm_turn_on_cpu_rail);

void msm_spm_reinit(void)
{
	unsigned int cpu;
	for_each_possible_cpu(cpu)
		msm_spm_drv_reinit(&per_cpu(msm_cpu_spm_device.reg_data, cpu));
}
EXPORT_SYMBOL(msm_spm_reinit);

/**
 * msm_spm_set_low_power_mode() - Configure SPM start address for low power mode
 * @mode: SPM LPM mode to enter
 * @notify_rpm: Notify RPM in this mode
 */
int msm_spm_set_low_power_mode(unsigned int mode, bool notify_rpm)
{
	struct msm_spm_device *dev = &__get_cpu_var(msm_cpu_spm_device);
	return msm_spm_dev_set_low_power_mode(dev, mode, notify_rpm);
}
EXPORT_SYMBOL(msm_spm_set_low_power_mode);

/**
 * msm_spm_init(): Board initalization function
 * @data: platform specific SPM register configuration data
 * @nr_devs: Number of SPM devices being initialized
 */
int __init msm_spm_init(struct msm_spm_platform_data *data, int nr_devs)
{
	unsigned int cpu;
	int ret = 0;

	BUG_ON((nr_devs < num_possible_cpus()) || !data);

	for_each_possible_cpu(cpu) {
		struct msm_spm_device *dev = &per_cpu(msm_cpu_spm_device, cpu);
		ret = msm_spm_dev_init(dev, &data[cpu]);
		if (ret < 0) {
			pr_warn("%s():failed CPU:%u ret:%d\n", __func__,
					cpu, ret);
			break;
		}
	}

	return ret;
}

#ifdef CONFIG_MSM_L2_SPM

/**
 * msm_spm_l2_set_low_power_mode(): Configure L2 SPM start address
 *                                  for low power mode
 * @mode: SPM LPM mode to enter
 * @notify_rpm: Notify RPM in this mode
 */
int msm_spm_l2_set_low_power_mode(unsigned int mode, bool notify_rpm)
{
	return msm_spm_dev_set_low_power_mode(
			&msm_spm_l2_device, mode, notify_rpm);
}
EXPORT_SYMBOL(msm_spm_l2_set_low_power_mode);

void msm_spm_l2_reinit(void)
{
	if (!msm_spm_l2_device.initialized)
		return;
	msm_spm_drv_reinit(&msm_spm_l2_device.reg_data);
}
EXPORT_SYMBOL(msm_spm_l2_reinit);

/**
 * msm_spm_apcs_set_vdd(): Set Apps processor core sub-system voltage
 * @vlevel: Encoded PMIC data.
 */
int msm_spm_apcs_set_vdd(unsigned int vlevel)
{
	if (!msm_spm_l2_device.initialized)
		return -ENXIO;
	return msm_spm_drv_set_vdd(&msm_spm_l2_device.reg_data, vlevel);
}
EXPORT_SYMBOL(msm_spm_apcs_set_vdd);

/**
 * msm_spm_apcs_set_phase(): Set number of SMPS phases.
 * phase_cnt: Number of phases to be set active
 */
int msm_spm_apcs_set_phase(unsigned int phase_cnt)
{
	if (!msm_spm_l2_device.initialized)
		return -ENXIO;
	return msm_spm_drv_set_pmic_data(&msm_spm_l2_device.reg_data,
			MSM_SPM_PMIC_PHASE_PORT, phase_cnt);
}
EXPORT_SYMBOL(msm_spm_apcs_set_phase);

/** msm_spm_enable_fts_lpm() : Enable FTS to switch to low power
 *                             when the cores are in low power modes
 * @mode: The mode configuration for FTS
 */
int msm_spm_enable_fts_lpm(uint32_t mode)
{
	if (!msm_spm_l2_device.initialized)
		return -ENXIO;
	return msm_spm_drv_set_pmic_data(&msm_spm_l2_device.reg_data,
			MSM_SPM_PMIC_PFM_PORT, mode);
}
EXPORT_SYMBOL(msm_spm_enable_fts_lpm);

/**
 * msm_spm_l2_init(): Board initialization function
 * @data: SPM target specific register configuration
 */
int __init msm_spm_l2_init(struct msm_spm_platform_data *data)
{
	return msm_spm_dev_init(&msm_spm_l2_device, data);
}
#endif

static int __devinit msm_spm_dev_probe(struct platform_device *pdev)
{
	int ret = 0;
	int cpu = 0;
	int i = 0;
	struct device_node *node = pdev->dev.of_node;
	struct msm_spm_platform_data spm_data;
	char *key = NULL;
	uint32_t val = 0;
	struct msm_spm_seq_entry modes[MSM_SPM_MODE_NR];
	size_t len = 0;
	struct msm_spm_device *dev = NULL;
	struct resource *res = NULL;
	uint32_t mode_count = 0;

	struct spm_of {
		char *key;
		uint32_t id;
	};

	struct spm_of spm_of_data[] = {
		{"qcom,saw2-cfg", MSM_SPM_REG_SAW2_CFG},
		{"qcom,saw2-avs-ctl", MSM_SPM_REG_SAW2_AVS_CTL},
		{"qcom,saw2-avs-hysteresis", MSM_SPM_REG_SAW2_AVS_HYSTERESIS},
		{"qcom,saw2-avs-limit", MSM_SPM_REG_SAW2_AVS_LIMIT},
		{"qcom,saw2-avs-dly", MSM_SPM_REG_SAW2_AVS_DLY},
		{"qcom,saw2-spm-dly", MSM_SPM_REG_SAW2_SPM_DLY},
		{"qcom,saw2-spm-ctl", MSM_SPM_REG_SAW2_SPM_CTL},
		{"qcom,saw2-pmic-data0", MSM_SPM_REG_SAW2_PMIC_DATA_0},
		{"qcom,saw2-pmic-data1", MSM_SPM_REG_SAW2_PMIC_DATA_1},
		{"qcom,saw2-pmic-data2", MSM_SPM_REG_SAW2_PMIC_DATA_2},
		{"qcom,saw2-pmic-data3", MSM_SPM_REG_SAW2_PMIC_DATA_3},
		{"qcom,saw2-pmic-data4", MSM_SPM_REG_SAW2_PMIC_DATA_4},
		{"qcom,saw2-pmic-data5", MSM_SPM_REG_SAW2_PMIC_DATA_5},
		{"qcom,saw2-pmic-data6", MSM_SPM_REG_SAW2_PMIC_DATA_6},
		{"qcom,saw2-pmic-data7", MSM_SPM_REG_SAW2_PMIC_DATA_7},
	};

	struct mode_of {
		char *key;
		uint32_t id;
		uint32_t notify_rpm;
	};

	struct mode_of of_cpu_modes[] = {
		{"qcom,saw2-spm-cmd-wfi", MSM_SPM_MODE_CLOCK_GATING, 0},
		{"qcom,saw2-spm-cmd-ret", MSM_SPM_MODE_POWER_RETENTION, 0},
		{"qcom,saw2-spm-cmd-spc", MSM_SPM_MODE_POWER_COLLAPSE, 0},
		{"qcom,saw2-spm-cmd-pc", MSM_SPM_MODE_POWER_COLLAPSE, 1},
	};

	struct mode_of of_l2_modes[] = {
		{"qcom,saw2-spm-cmd-ret", MSM_SPM_L2_MODE_RETENTION, 1},
		{"qcom,saw2-spm-cmd-gdhs", MSM_SPM_L2_MODE_GDHS, 1},
		{"qcom,saw2-spm-cmd-pc", MSM_SPM_L2_MODE_POWER_COLLAPSE, 1},
	};

	struct mode_of *mode_of_data;
	int num_modes;

	memset(&spm_data, 0, sizeof(struct msm_spm_platform_data));
	memset(&modes, 0,
		(MSM_SPM_MODE_NR - 2) * sizeof(struct msm_spm_seq_entry));

	key = "qcom,core-id";
	ret = of_property_read_u32(node, key, &val);
	if (ret)
		goto fail;
	cpu = val;

	/*
	 * Device with id 0..NR_CPUS are SPM for apps cores
	 * Device with id 0xFFFF is for L2 SPM.
	 */
	if (cpu >= 0 && cpu < num_possible_cpus()) {
		mode_of_data = of_cpu_modes;
		num_modes = ARRAY_SIZE(of_cpu_modes);
		dev = &per_cpu(msm_cpu_spm_device, cpu);

	} else if (cpu == 0xffff) {
		mode_of_data = of_l2_modes;
		num_modes = ARRAY_SIZE(of_l2_modes);
		dev = &msm_spm_l2_device;
	} else
		return ret;

	key = "qcom,saw2-ver-reg";
	ret = of_property_read_u32(node, key, &val);
	if (ret)
		goto fail;
	spm_data.ver_reg = val;

	key = "qcom,vctl-timeout-us";
	ret = of_property_read_u32(node, key, &val);
	if (!ret)
		spm_data.vctl_timeout_us = val;
	else if (cpu == 0xffff)
		goto fail;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res)
		goto fail;

	spm_data.reg_base_addr = devm_ioremap(&pdev->dev, res->start,
					resource_size(res));
	if (!spm_data.reg_base_addr)
		return -ENOMEM;

	spm_data.vctl_port = -1;
	spm_data.phase_port = -1;
	spm_data.pfm_port = -1;

	/* optional */
	if (dev == &msm_spm_l2_device) {
		key = "qcom,vctl-port";
		ret = of_property_read_u32(node, key, &val);
		if (!ret)
			spm_data.vctl_port = val;

		key = "qcom,phase-port";
		ret = of_property_read_u32(node, key, &val);
		if (!ret)
			spm_data.phase_port = val;

		key = "qcom,pfm-port";
		ret = of_property_read_u32(node, key, &val);
		if (!ret)
			spm_data.pfm_port = val;
	}

	for (i = 0; i < ARRAY_SIZE(spm_of_data); i++) {
		ret = of_property_read_u32(node, spm_of_data[i].key, &val);
		if (ret)
			continue;
		spm_data.reg_init_values[spm_of_data[i].id] = val;
	}

	for (i = 0; i < num_modes; i++) {
		key = mode_of_data[i].key;
		modes[mode_count].cmd =
			(uint8_t *)of_get_property(node, key, &len);
		if (!modes[mode_count].cmd)
			continue;
		modes[mode_count].mode = mode_of_data[i].id;
		modes[mode_count].notify_rpm = mode_of_data[i].notify_rpm;
		mode_count++;
	}

	spm_data.modes = modes;
	spm_data.num_modes = mode_count;

	ret = msm_spm_dev_init(dev, &spm_data);

	if (ret < 0)
		pr_warn("%s():failed core-id:%u ret:%d\n", __func__, cpu, ret);

	return ret;

fail:
	pr_err("%s: Failed reading node=%s, key=%s\n",
			__func__, node->full_name, key);
	return -EFAULT;
}

static struct of_device_id msm_spm_match_table[] = {
	{.compatible = "qcom,spm-v2"},
	{},
};

static struct platform_driver msm_spm_device_driver = {
	.probe = msm_spm_dev_probe,
	.driver = {
		.name = "spm-v2",
		.owner = THIS_MODULE,
		.of_match_table = msm_spm_match_table,
	},
};

/**
 * msm_spm_device_init(): Device tree initialization function
 */
int __init msm_spm_device_init(void)
{
	return platform_driver_register(&msm_spm_device_driver);
}