/* Copyright (c) 2011-2012, Code Aurora Forum. 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/elf.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/iopoll.h>
#include <linux/of.h>
#include <linux/regulator/consumer.h>

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

#define PRONTO_PMU_COMMON_GDSCR				0x24
#define PRONTO_PMU_COMMON_GDSCR_SW_COLLAPSE		BIT(0)
#define CLK_DIS_WAIT					12
#define EN_FEW_WAIT					16
#define EN_REST_WAIT					20

#define PRONTO_PMU_COMMON_CPU_CBCR			0x30
#define PRONTO_PMU_COMMON_CPU_CBCR_CLK_EN		BIT(0)
#define PRONTO_PMU_COMMON_CPU_CLK_OFF			BIT(31)

#define PRONTO_PMU_COMMON_AHB_CBCR			0x34
#define PRONTO_PMU_COMMON_AHB_CBCR_CLK_EN		BIT(0)
#define PRONTO_PMU_COMMON_AHB_CLK_OFF			BIT(31)

#define PRONTO_PMU_COMMON_CSR				0x1040
#define PRONTO_PMU_COMMON_CSR_A2XB_CFG_EN		BIT(0)

#define PRONTO_PMU_SOFT_RESET				0x104C
#define PRONTO_PMU_SOFT_RESET_CRCM_CCPU_SOFT_RESET	BIT(10)

#define PRONTO_PMU_CCPU_CTL				0x2000
#define PRONTO_PMU_CCPU_CTL_REMAP_EN			BIT(2)
#define PRONTO_PMU_CCPU_CTL_HIGH_IVT			BIT(0)

#define PRONTO_PMU_CCPU_BOOT_REMAP_ADDR			0x2004

#define CLK_CTL_WCNSS_RESTART_BIT			BIT(0)

#define AXI_HALTREQ					0x0
#define AXI_HALTACK					0x4
#define AXI_IDLE					0x8

#define HALT_ACK_TIMEOUT_US				500000
#define CLK_UPDATE_TIMEOUT_US				500000

struct pronto_data {
	void __iomem *base;
	void __iomem *reset_base;
	void __iomem *axi_halt_base;
	unsigned long start_addr;
	struct pil_device *pil;
	struct clk *cxo;
	struct regulator *vreg;
};

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

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

static void pil_pronto_remove_proxy_vote(struct pil_desc *pil)
{
	struct pronto_data *drv = dev_get_drvdata(pil->dev);
	regulator_disable(drv->vreg);
	clk_disable_unprepare(drv->cxo);
}

static int pil_pronto_init_image(struct pil_desc *pil, const u8 *metadata,
		size_t size)
{
	const struct elf32_hdr *ehdr = (struct elf32_hdr *)metadata;
	struct pronto_data *drv = dev_get_drvdata(pil->dev);
	drv->start_addr = ehdr->e_entry;
	return 0;
}

static int pil_pronto_reset(struct pil_desc *pil)
{
	u32 reg;
	int rc;
	struct pronto_data *drv = dev_get_drvdata(pil->dev);
	void __iomem *base = drv->base;
	unsigned long start_addr = drv->start_addr;

	/* Deassert reset to subsystem and wait for propagation */
	reg = readl_relaxed(drv->reset_base);
	reg &= ~CLK_CTL_WCNSS_RESTART_BIT;
	writel_relaxed(reg, drv->reset_base);
	mb();
	udelay(2);

	/* Configure boot address */
	writel_relaxed(start_addr >> 16, base +
			PRONTO_PMU_CCPU_BOOT_REMAP_ADDR);

	/* Use the high vector table */
	reg = readl_relaxed(base + PRONTO_PMU_CCPU_CTL);
	reg |= PRONTO_PMU_CCPU_CTL_REMAP_EN | PRONTO_PMU_CCPU_CTL_HIGH_IVT;
	writel_relaxed(reg, base + PRONTO_PMU_CCPU_CTL);

	/* Turn on AHB clock of common_ss */
	reg = readl_relaxed(base + PRONTO_PMU_COMMON_AHB_CBCR);
	reg |= PRONTO_PMU_COMMON_AHB_CBCR_CLK_EN;
	writel_relaxed(reg, base + PRONTO_PMU_COMMON_AHB_CBCR);

	/* Turn on CPU clock of common_ss */
	reg = readl_relaxed(base + PRONTO_PMU_COMMON_CPU_CBCR);
	reg |= PRONTO_PMU_COMMON_CPU_CBCR_CLK_EN;
	writel_relaxed(reg, base + PRONTO_PMU_COMMON_CPU_CBCR);

	/* Enable A2XB bridge */
	reg = readl_relaxed(base + PRONTO_PMU_COMMON_CSR);
	reg |= PRONTO_PMU_COMMON_CSR_A2XB_CFG_EN;
	writel_relaxed(reg, base + PRONTO_PMU_COMMON_CSR);

	/* Enable common_ss power */
	reg = readl_relaxed(base + PRONTO_PMU_COMMON_GDSCR);
	reg &= ~PRONTO_PMU_COMMON_GDSCR_SW_COLLAPSE;
	writel_relaxed(reg, base + PRONTO_PMU_COMMON_GDSCR);

	/* Wait for AHB clock to be on */
	rc = readl_tight_poll_timeout(base + PRONTO_PMU_COMMON_AHB_CBCR,
				      reg,
				      !(reg & PRONTO_PMU_COMMON_AHB_CLK_OFF),
				      CLK_UPDATE_TIMEOUT_US);
	if (rc) {
		dev_err(pil->dev, "pronto common ahb clk enable timeout\n");
		return rc;
	}

	/* Wait for CPU clock to be on */
	rc = readl_tight_poll_timeout(base + PRONTO_PMU_COMMON_CPU_CBCR,
				      reg,
				      !(reg & PRONTO_PMU_COMMON_CPU_CLK_OFF),
				      CLK_UPDATE_TIMEOUT_US);
	if (rc) {
		dev_err(pil->dev, "pronto common cpu clk enable timeout\n");
		return rc;
	}

	/* Deassert ARM9 software reset */
	reg = readl_relaxed(base + PRONTO_PMU_SOFT_RESET);
	reg &= ~PRONTO_PMU_SOFT_RESET_CRCM_CCPU_SOFT_RESET;
	writel_relaxed(reg, base + PRONTO_PMU_SOFT_RESET);

	return 0;
}

static int pil_pronto_shutdown(struct pil_desc *pil)
{
	struct pronto_data *drv = dev_get_drvdata(pil->dev);
	int ret;
	u32 reg, status;

	/* Halt A2XB */
	writel_relaxed(1, drv->axi_halt_base + AXI_HALTREQ);
	ret = readl_poll_timeout(drv->axi_halt_base + AXI_HALTACK,
				status, status, 50, HALT_ACK_TIMEOUT_US);
	if (ret)
		dev_err(pil->dev, "Port halt timeout\n");
	else if (!readl_relaxed(drv->axi_halt_base + AXI_IDLE))
		dev_err(pil->dev, "Port halt failed\n");

	writel_relaxed(0, drv->axi_halt_base + AXI_HALTREQ);

	/* Assert reset to Pronto */
	reg = readl_relaxed(drv->reset_base);
	reg |= CLK_CTL_WCNSS_RESTART_BIT;
	writel_relaxed(reg, drv->reset_base);

	/* Wait for reset to complete */
	mb();
	usleep_range(1000, 2000);

	/* Deassert reset to subsystem and wait for propagation */
	reg = readl_relaxed(drv->reset_base);
	reg &= ~CLK_CTL_WCNSS_RESTART_BIT;
	writel_relaxed(reg, drv->reset_base);
	mb();
	udelay(2);

	return 0;
}

static struct pil_reset_ops pil_pronto_ops = {
	.init_image = pil_pronto_init_image,
	.auth_and_reset = pil_pronto_reset,
	.shutdown = pil_pronto_shutdown,
	.proxy_vote = pil_pronto_make_proxy_vote,
	.proxy_unvote = pil_pronto_remove_proxy_vote,
};

static int __devinit pil_pronto_probe(struct platform_device *pdev)
{
	struct pronto_data *drv;
	struct resource *res;
	struct pil_desc *desc;
	int ret;
	uint32_t regval;

	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pmu_base");
	if (!res)
		return -EINVAL;

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

	drv->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
	if (!drv->base)
		return -ENOMEM;

	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "clk_base");
	if (!res)
		return -EINVAL;

	drv->reset_base = devm_ioremap(&pdev->dev, res->start,
					resource_size(res));

	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "halt_base");
	if (!res)
		return -EINVAL;

	drv->axi_halt_base = devm_ioremap(&pdev->dev, res->start,
					  resource_size(res));

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

	ret = of_property_read_string(pdev->dev.of_node, "qcom,firmware-name",
				      &desc->name);
	if (ret)
		return ret;

	desc->dev = &pdev->dev;
	desc->owner = THIS_MODULE;
	desc->proxy_timeout = 10000;

	/* TODO: need to add secure boot when the support is available */
	desc->ops = &pil_pronto_ops;
	dev_info(&pdev->dev, "using non-secure boot\n");

	drv->vreg = devm_regulator_get(&pdev->dev, "vdd_pronto_pll");
	if (IS_ERR(drv->vreg)) {
		dev_err(&pdev->dev, "failed to get pronto pll supply");
		return PTR_ERR(drv->vreg);
	}

	ret = regulator_set_voltage(drv->vreg, 1800000, 1800000);
	if (ret) {
		dev_err(&pdev->dev, "failed to set pll supply voltage\n");
		return ret;
	}

	ret = regulator_set_optimum_mode(drv->vreg, 18000);
	if (ret < 0) {
		dev_err(&pdev->dev, "failed to set pll supply mode\n");
		return ret;
	}

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

	drv->pil = msm_pil_register(desc);
	if (IS_ERR(drv->pil))
		return PTR_ERR(drv->pil);

	/* Initialize common_ss GDSCR to wait 4 cycles between states */
	regval = readl_relaxed(drv->base + PRONTO_PMU_COMMON_GDSCR)
		& PRONTO_PMU_COMMON_GDSCR_SW_COLLAPSE;
	regval |= (2 << EN_REST_WAIT) | (2 << EN_FEW_WAIT)
		  | (2 << CLK_DIS_WAIT);
	writel_relaxed(regval, drv->base + PRONTO_PMU_COMMON_GDSCR);

	return 0;
}

static int __devexit pil_pronto_remove(struct platform_device *pdev)
{
	struct pronto_data *drv = platform_get_drvdata(pdev);
	msm_pil_unregister(drv->pil);
	return 0;
}

static struct of_device_id msm_pil_pronto_match[] = {
	{.compatible = "qcom,pil-pronto"},
	{}
};

static struct platform_driver pil_pronto_driver = {
	.probe = pil_pronto_probe,
	.remove = __devexit_p(pil_pronto_remove),
	.driver = {
		.name = "pil_pronto",
		.owner = THIS_MODULE,
		.of_match_table = msm_pil_pronto_match,
	},
};

static int __init pil_pronto_init(void)
{
	return platform_driver_register(&pil_pronto_driver);
}
module_init(pil_pronto_init);

static void __exit pil_pronto_exit(void)
{
	platform_driver_unregister(&pil_pronto_driver);
}
module_exit(pil_pronto_exit);

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