/* 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/kernel.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/wcnss_wlan.h>

#include <mach/subsystem_restart.h>
#include <mach/ramdump.h>

#include "peripheral-loader.h"
#include "scm-pas.h"
#include "smd_private.h"

#define RIVA_PMU_A2XB_CFG		0xB8
#define RIVA_PMU_A2XB_CFG_EN		BIT(0)

#define RIVA_PMU_CFG			0x28
#define RIVA_PMU_CFG_WARM_BOOT		BIT(0)
#define RIVA_PMU_CFG_IRIS_XO_MODE	0x6
#define RIVA_PMU_CFG_IRIS_XO_MODE_48	(3 << 1)

#define RIVA_PMU_OVRD_EN		0x2C
#define RIVA_PMU_OVRD_EN_CCPU_RESET	BIT(0)
#define RIVA_PMU_OVRD_EN_CCPU_CLK	BIT(1)

#define RIVA_PMU_OVRD_VAL		0x30
#define RIVA_PMU_OVRD_VAL_CCPU_RESET	BIT(0)
#define RIVA_PMU_OVRD_VAL_CCPU_CLK	BIT(1)

#define RIVA_PMU_CCPU_CTL		0x9C
#define RIVA_PMU_CCPU_CTL_HIGH_IVT	BIT(0)
#define RIVA_PMU_CCPU_CTL_REMAP_EN	BIT(2)

#define RIVA_PMU_CCPU_BOOT_REMAP_ADDR	0xA0

#define RIVA_PLL_MODE			0x31A0
#define PLL_MODE_OUTCTRL		BIT(0)
#define PLL_MODE_BYPASSNL		BIT(1)
#define PLL_MODE_RESET_N		BIT(2)
#define PLL_MODE_REF_XO_SEL		0x30
#define PLL_MODE_REF_XO_SEL_CXO		(2 << 4)
#define PLL_MODE_REF_XO_SEL_RF		(3 << 4)
#define RIVA_PLL_L_VAL			0x31A4
#define RIVA_PLL_M_VAL			0x31A8
#define RIVA_PLL_N_VAL			0x31Ac
#define RIVA_PLL_CONFIG			0x31B4
#define RIVA_RESET			0x35E0

#define RIVA_PMU_ROOT_CLK_SEL		0xC8
#define RIVA_PMU_ROOT_CLK_SEL_3		BIT(2)

#define RIVA_PMU_CLK_ROOT3			0x78
#define RIVA_PMU_CLK_ROOT3_ENA			BIT(0)
#define RIVA_PMU_CLK_ROOT3_SRC0_DIV		0x3C
#define RIVA_PMU_CLK_ROOT3_SRC0_DIV_2		(1 << 2)
#define RIVA_PMU_CLK_ROOT3_SRC0_SEL		0x1C0
#define RIVA_PMU_CLK_ROOT3_SRC0_SEL_RIVA	(1 << 6)
#define RIVA_PMU_CLK_ROOT3_SRC1_DIV		0x1E00
#define RIVA_PMU_CLK_ROOT3_SRC1_DIV_2		(1 << 9)
#define RIVA_PMU_CLK_ROOT3_SRC1_SEL		0xE000
#define RIVA_PMU_CLK_ROOT3_SRC1_SEL_RIVA	(1 << 13)

struct riva_data {
	void __iomem *base;
	void __iomem *cbase;
	struct clk *xo;
	struct regulator *pll_supply;
	struct pil_desc pil_desc;
	int irq;
	int crash;
	int rst_in_progress;
	struct subsys_device *subsys;
	struct subsys_desc subsys_desc;
	struct delayed_work cancel_work;
	struct ramdump_device *ramdump_dev;
};

static bool cxo_is_needed(struct riva_data *drv)
{
	u32 reg = readl_relaxed(drv->base + RIVA_PMU_CFG);
	return (reg & RIVA_PMU_CFG_IRIS_XO_MODE)
		!= RIVA_PMU_CFG_IRIS_XO_MODE_48;
}

static int pil_riva_make_proxy_vote(struct pil_desc *pil)
{
	struct riva_data *drv = dev_get_drvdata(pil->dev);
	int ret;

	ret = regulator_enable(drv->pll_supply);
	if (ret) {
		dev_err(pil->dev, "failed to enable pll supply\n");
		goto err;
	}
	ret = clk_prepare_enable(drv->xo);
	if (ret) {
		dev_err(pil->dev, "failed to enable xo\n");
		goto err_clk;
	}
	return 0;
err_clk:
	regulator_disable(drv->pll_supply);
err:
	return ret;
}

static void pil_riva_remove_proxy_vote(struct pil_desc *pil)
{
	struct riva_data *drv = dev_get_drvdata(pil->dev);
	regulator_disable(drv->pll_supply);
	clk_disable_unprepare(drv->xo);
}

static int pil_riva_reset(struct pil_desc *pil)
{
	u32 reg, sel;
	struct riva_data *drv = dev_get_drvdata(pil->dev);
	void __iomem *base = drv->base;
	phys_addr_t start_addr = pil_get_entry_addr(pil);
	void __iomem *cbase = drv->cbase;
	bool use_cxo = cxo_is_needed(drv);

	/* Enable A2XB bridge */
	reg = readl_relaxed(base + RIVA_PMU_A2XB_CFG);
	reg |= RIVA_PMU_A2XB_CFG_EN;
	writel_relaxed(reg, base + RIVA_PMU_A2XB_CFG);

	/* Program PLL 13 to 960 MHz */
	reg = readl_relaxed(cbase + RIVA_PLL_MODE);
	reg &= ~(PLL_MODE_BYPASSNL | PLL_MODE_OUTCTRL | PLL_MODE_RESET_N);
	writel_relaxed(reg, cbase + RIVA_PLL_MODE);

	if (use_cxo)
		writel_relaxed(0x40000C00 | 50, cbase + RIVA_PLL_L_VAL);
	else
		writel_relaxed(0x40000C00 | 40, cbase + RIVA_PLL_L_VAL);
	writel_relaxed(0, cbase + RIVA_PLL_M_VAL);
	writel_relaxed(1, cbase + RIVA_PLL_N_VAL);
	writel_relaxed(0x01495227, cbase + RIVA_PLL_CONFIG);

	reg = readl_relaxed(cbase + RIVA_PLL_MODE);
	reg &= ~(PLL_MODE_REF_XO_SEL);
	reg |= use_cxo ? PLL_MODE_REF_XO_SEL_CXO : PLL_MODE_REF_XO_SEL_RF;
	writel_relaxed(reg, cbase + RIVA_PLL_MODE);

	/* Enable PLL 13 */
	reg |= PLL_MODE_BYPASSNL;
	writel_relaxed(reg, cbase + RIVA_PLL_MODE);

	/*
	 * H/W requires a 5us delay between disabling the bypass and
	 * de-asserting the reset. Delay 10us just to be safe.
	 */
	mb();
	usleep_range(10, 20);

	reg |= PLL_MODE_RESET_N;
	writel_relaxed(reg, cbase + RIVA_PLL_MODE);
	reg |= PLL_MODE_OUTCTRL;
	writel_relaxed(reg, cbase + RIVA_PLL_MODE);

	/* Wait for PLL to settle */
	mb();
	usleep_range(50, 100);

	/* Configure cCPU for 240 MHz */
	sel = readl_relaxed(base + RIVA_PMU_ROOT_CLK_SEL);
	reg = readl_relaxed(base + RIVA_PMU_CLK_ROOT3);
	if (sel & RIVA_PMU_ROOT_CLK_SEL_3) {
		reg &= ~(RIVA_PMU_CLK_ROOT3_SRC0_SEL |
			 RIVA_PMU_CLK_ROOT3_SRC0_DIV);
		reg |= RIVA_PMU_CLK_ROOT3_SRC0_SEL_RIVA |
		       RIVA_PMU_CLK_ROOT3_SRC0_DIV_2;
	} else {
		reg &= ~(RIVA_PMU_CLK_ROOT3_SRC1_SEL |
			 RIVA_PMU_CLK_ROOT3_SRC1_DIV);
		reg |= RIVA_PMU_CLK_ROOT3_SRC1_SEL_RIVA |
		       RIVA_PMU_CLK_ROOT3_SRC1_DIV_2;
	}
	writel_relaxed(reg, base + RIVA_PMU_CLK_ROOT3);
	reg |= RIVA_PMU_CLK_ROOT3_ENA;
	writel_relaxed(reg, base + RIVA_PMU_CLK_ROOT3);
	reg = readl_relaxed(base + RIVA_PMU_ROOT_CLK_SEL);
	reg ^= RIVA_PMU_ROOT_CLK_SEL_3;
	writel_relaxed(reg, base + RIVA_PMU_ROOT_CLK_SEL);

	/* Use the high vector table */
	reg = readl_relaxed(base + RIVA_PMU_CCPU_CTL);
	reg |= RIVA_PMU_CCPU_CTL_HIGH_IVT | RIVA_PMU_CCPU_CTL_REMAP_EN;
	writel_relaxed(reg, base + RIVA_PMU_CCPU_CTL);

	/* Set base memory address */
	writel_relaxed(start_addr >> 16, base + RIVA_PMU_CCPU_BOOT_REMAP_ADDR);

	/* Clear warmboot bit indicating this is a cold boot */
	reg = readl_relaxed(base + RIVA_PMU_CFG);
	reg &= ~(RIVA_PMU_CFG_WARM_BOOT);
	writel_relaxed(reg, base + RIVA_PMU_CFG);

	/* Enable the cCPU clock */
	reg = readl_relaxed(base + RIVA_PMU_OVRD_VAL);
	reg |= RIVA_PMU_OVRD_VAL_CCPU_CLK;
	writel_relaxed(reg, base + RIVA_PMU_OVRD_VAL);

	/* Take cCPU out of reset */
	reg |= RIVA_PMU_OVRD_VAL_CCPU_RESET;
	writel_relaxed(reg, base + RIVA_PMU_OVRD_VAL);

	return 0;
}

static int pil_riva_shutdown(struct pil_desc *pil)
{
	struct riva_data *drv = dev_get_drvdata(pil->dev);
	void __iomem *cbase = drv->cbase;

	/* Assert reset to Riva */
	writel_relaxed(1, cbase + RIVA_RESET);
	mb();
	usleep_range(1000, 2000);

	/* Deassert reset to Riva */
	writel_relaxed(0, cbase + RIVA_RESET);
	mb();

	return 0;
}

static struct pil_reset_ops pil_riva_ops = {
	.auth_and_reset = pil_riva_reset,
	.shutdown = pil_riva_shutdown,
	.proxy_vote = pil_riva_make_proxy_vote,
	.proxy_unvote = pil_riva_remove_proxy_vote,
};

static int pil_riva_init_image_trusted(struct pil_desc *pil,
		const u8 *metadata, size_t size)
{
	return pas_init_image(PAS_WCNSS, metadata, size);
}

static int pil_riva_reset_trusted(struct pil_desc *pil)
{
	return pas_auth_and_reset(PAS_WCNSS);
}

static int pil_riva_shutdown_trusted(struct pil_desc *pil)
{
	return pas_shutdown(PAS_WCNSS);
}

static struct pil_reset_ops pil_riva_ops_trusted = {
	.init_image = pil_riva_init_image_trusted,
	.auth_and_reset = pil_riva_reset_trusted,
	.shutdown = pil_riva_shutdown_trusted,
	.proxy_vote = pil_riva_make_proxy_vote,
	.proxy_unvote = pil_riva_remove_proxy_vote,
};

static int enable_riva_ssr;

static int enable_riva_ssr_set(const char *val, struct kernel_param *kp)
{
	int ret;

	ret = param_set_int(val, kp);
	if (ret)
		return ret;

	if (enable_riva_ssr)
		pr_info("Subsystem restart activated for riva.\n");

	return 0;
}
module_param_call(enable_riva_ssr, enable_riva_ssr_set, param_get_int,
		 &enable_riva_ssr, S_IRUGO | S_IWUSR);

static void smsm_state_cb_hdlr(void *data, uint32_t old_state,
			       uint32_t new_state)
{
	struct riva_data *drv = data;
	char *smem_reset_reason;
	char buffer[81];
	unsigned smem_reset_size;
	unsigned size;

	drv->crash = true;
	if (!(new_state & SMSM_RESET))
		return;

	if (drv->rst_in_progress) {
		pr_err("riva: Ignoring smsm reset req, restart in progress\n");
		return;
	}

	pr_err("riva: smsm state changed to smsm reset\n");

	smem_reset_reason = smem_get_entry(SMEM_SSR_REASON_WCNSS0,
		&smem_reset_size);

	if (!smem_reset_reason || !smem_reset_size) {
		pr_err("wcnss subsystem failure reason:\n"
		       "(unknown, smem_get_entry failed)");
	} else if (!smem_reset_reason[0]) {
		pr_err("wcnss subsystem failure reason:\n"
		       "(unknown, init string found)");
	} else {
		size = smem_reset_size < sizeof(buffer) ? smem_reset_size :
				(sizeof(buffer) - 1);
		memcpy(buffer, smem_reset_reason, size);
		buffer[size] = '\0';
		pr_err("wcnss subsystem failure reason: %s\n", buffer);
		memset(smem_reset_reason, 0, smem_reset_size);
		wmb();
	}

	drv->rst_in_progress = 1;
	subsystem_restart_dev(drv->subsys);
}

static irqreturn_t riva_wdog_bite_irq_hdlr(int irq, void *dev_id)
{
	struct riva_data *drv = dev_id;

	drv->crash = true;
	if (drv->rst_in_progress) {
		pr_err("Ignoring riva bite irq, restart in progress\n");
		return IRQ_HANDLED;
	}
	if (!enable_riva_ssr)
		panic("Watchdog bite received from Riva");

	drv->rst_in_progress = 1;
	wcnss_riva_log_debug_regs();
	subsystem_restart_dev(drv->subsys);

	return IRQ_HANDLED;
}

static void riva_post_bootup(struct work_struct *work)
{
	struct platform_device *pdev = wcnss_get_platform_device();
	struct wcnss_wlan_config *pwlanconfig = wcnss_get_wlan_config();

	wcnss_wlan_power(&pdev->dev, pwlanconfig, WCNSS_WLAN_SWITCH_OFF);
}

static int riva_start(const struct subsys_desc *desc)
{
	struct riva_data *drv;

	drv = container_of(desc, struct riva_data, subsys_desc);
	return pil_boot(&drv->pil_desc);
}

static void riva_stop(const struct subsys_desc *desc)
{
	struct riva_data *drv;

	drv = container_of(desc, struct riva_data, subsys_desc);
	pil_shutdown(&drv->pil_desc);
}

static int riva_shutdown(const struct subsys_desc *desc)
{
	struct riva_data *drv;

	drv = container_of(desc, struct riva_data, subsys_desc);
	pil_shutdown(&drv->pil_desc);
	flush_delayed_work(&drv->cancel_work);
	wcnss_flush_delayed_boot_votes();
	disable_irq_nosync(drv->irq);

	return 0;
}

static int riva_powerup(const struct subsys_desc *desc)
{
	struct riva_data *drv;
	struct platform_device *pdev = wcnss_get_platform_device();
	struct wcnss_wlan_config *pwlanconfig = wcnss_get_wlan_config();
	int ret = 0;

	drv = container_of(desc, struct riva_data, subsys_desc);
	if (pdev && pwlanconfig) {
		ret = wcnss_wlan_power(&pdev->dev, pwlanconfig,
					WCNSS_WLAN_SWITCH_ON);
		if (!ret)
			pil_boot(&drv->pil_desc);
	}
	drv->rst_in_progress = 0;
	enable_irq(drv->irq);
	schedule_delayed_work(&drv->cancel_work, msecs_to_jiffies(5000));

	return ret;
}

static int riva_ramdump(int enable, const struct subsys_desc *desc)
{
	struct riva_data *drv;

	drv = container_of(desc, struct riva_data, subsys_desc);

	if (!enable)
		return 0;

	return pil_do_ramdump(&drv->pil_desc, drv->ramdump_dev);
}

/* Riva crash handler */
static void riva_crash_shutdown(const struct subsys_desc *desc)
{
	struct riva_data *drv;

	drv = container_of(desc, struct riva_data, subsys_desc);
	pr_err("riva crash shutdown %d\n", drv->crash);
	if (drv->crash != true)
		smsm_change_state(SMSM_APPS_STATE, SMSM_RESET, SMSM_RESET);
}

static int __devinit pil_riva_probe(struct platform_device *pdev)
{
	struct riva_data *drv;
	struct resource *res;
	struct pil_desc *desc;
	int ret;

	drv = devm_kzalloc(&pdev->dev, sizeof(*drv), GFP_KERNEL);
	if (!drv)
		return -ENOMEM;
	platform_set_drvdata(pdev, drv);


	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	drv->base = devm_request_and_ioremap(&pdev->dev, res);
	if (!drv->base)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
	drv->cbase = devm_request_and_ioremap(&pdev->dev, res);
	if (!drv->cbase)
		return -ENOMEM;

	drv->pll_supply = devm_regulator_get(&pdev->dev, "pll_vdd");
	if (IS_ERR(drv->pll_supply)) {
		dev_err(&pdev->dev, "failed to get pll supply\n");
		return PTR_ERR(drv->pll_supply);
	}
	if (regulator_count_voltages(drv->pll_supply) > 0) {
		ret = regulator_set_voltage(drv->pll_supply, 1800000, 1800000);
		if (ret) {
			dev_err(&pdev->dev,
				"failed to set pll supply voltage\n");
			return ret;
		}

		ret = regulator_set_optimum_mode(drv->pll_supply, 100000);
		if (ret < 0) {
			dev_err(&pdev->dev,
				"failed to set pll supply optimum mode\n");
			return ret;
		}
	}

	drv->irq = platform_get_irq(pdev, 0);
	if (drv->irq < 0)
		return drv->irq;

	drv->xo = devm_clk_get(&pdev->dev, "cxo");
	if (IS_ERR(drv->xo))
		return PTR_ERR(drv->xo);

	desc = &drv->pil_desc;
	desc->name = "wcnss";
	desc->dev = &pdev->dev;
	desc->owner = THIS_MODULE;
	desc->proxy_timeout = 10000;

	if (pas_supported(PAS_WCNSS) > 0) {
		desc->ops = &pil_riva_ops_trusted;
		dev_info(&pdev->dev, "using secure boot\n");
	} else {
		desc->ops = &pil_riva_ops;
		dev_info(&pdev->dev, "using non-secure boot\n");
	}
	ret = pil_desc_init(desc);

	ret = smsm_state_cb_register(SMSM_WCNSS_STATE, SMSM_RESET,
					smsm_state_cb_hdlr, drv);
	if (ret < 0)
		goto err_smsm;

	drv->subsys_desc.name = "wcnss";
	drv->subsys_desc.dev = &pdev->dev;
	drv->subsys_desc.owner = THIS_MODULE;
	drv->subsys_desc.start = riva_start;
	drv->subsys_desc.stop = riva_stop;
	drv->subsys_desc.shutdown = riva_shutdown;
	drv->subsys_desc.powerup = riva_powerup;
	drv->subsys_desc.ramdump = riva_ramdump;
	drv->subsys_desc.crash_shutdown = riva_crash_shutdown;

	INIT_DELAYED_WORK(&drv->cancel_work, riva_post_bootup);

	drv->ramdump_dev = create_ramdump_device("riva", &pdev->dev);
	if (!drv->ramdump_dev) {
		ret = -ENOMEM;
		goto err_ramdump;
	}

	drv->subsys = subsys_register(&drv->subsys_desc);
	if (IS_ERR(drv->subsys)) {
		ret = PTR_ERR(drv->subsys);
		goto err_subsys;
	}

	ret = devm_request_irq(&pdev->dev, drv->irq, riva_wdog_bite_irq_hdlr,
			IRQF_TRIGGER_RISING, "riva_wdog", drv);
	if (ret < 0)
		goto err;

	return 0;
err:
	subsys_unregister(drv->subsys);
err_subsys:
	destroy_ramdump_device(drv->ramdump_dev);
err_ramdump:
	smsm_state_cb_deregister(SMSM_WCNSS_STATE, SMSM_RESET,
					smsm_state_cb_hdlr, drv);
err_smsm:
	pil_desc_release(desc);
	return ret;
}

static int __devexit pil_riva_remove(struct platform_device *pdev)
{
	struct riva_data *drv = platform_get_drvdata(pdev);

	subsys_unregister(drv->subsys);
	destroy_ramdump_device(drv->ramdump_dev);
	smsm_state_cb_deregister(SMSM_WCNSS_STATE, SMSM_RESET,
					smsm_state_cb_hdlr, drv);
	pil_desc_release(&drv->pil_desc);

	return 0;
}

static struct platform_driver pil_riva_driver = {
	.probe = pil_riva_probe,
	.remove = __devexit_p(pil_riva_remove),
	.driver = {
		.name = "pil_riva",
		.owner = THIS_MODULE,
	},
};

static int __init pil_riva_init(void)
{
	return platform_driver_register(&pil_riva_driver);
}
module_init(pil_riva_init);

static void __exit pil_riva_exit(void)
{
	platform_driver_unregister(&pil_riva_driver);
}
module_exit(pil_riva_exit);

MODULE_DESCRIPTION("Support for booting RIVA (WCNSS) processors");
MODULE_LICENSE("GPL v2");