/*
   * Copyright (c) 2015-2016 MediaTek Inc.
   * Author: Yong Wu <yong.wu@mediatek.com>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License 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/clk.h>
  #include <linux/component.h>
  #include <linux/device.h>
  #include <linux/err.h>
  #include <linux/io.h>
  #include <linux/of.h>
  #include <linux/of_platform.h>
  #include <linux/platform_device.h>
  #include <linux/pm_runtime.h>
  #include <soc/mediatek/smi.h>

  #include <dt-bindings/memory/mt2701-larb-port.h>

  
  #define SMI_LARB_MMU_EN		0xf00

  #define REG_SMI_SECUR_CON_BASE		0x5c0
  
  /* every register control 8 port, register offset 0x4 */
  #define REG_SMI_SECUR_CON_OFFSET(id)	(((id) >> 3) << 2)
  #define REG_SMI_SECUR_CON_ADDR(id)	\
  	(REG_SMI_SECUR_CON_BASE + REG_SMI_SECUR_CON_OFFSET(id))
  
  /*
   * every port have 4 bit to control, bit[port + 3] control virtual or physical,
   * bit[port + 2 : port + 1] control the domain, bit[port] control the security
   * or non-security.
   */
  #define SMI_SECUR_CON_VAL_MSK(id)	(~(0xf << (((id) & 0x7) << 2)))
  #define SMI_SECUR_CON_VAL_VIRT(id)	BIT((((id) & 0x7) << 2) + 3)
  /* mt2701 domain should be set to 3 */
  #define SMI_SECUR_CON_VAL_DOMAIN(id)	(0x3 << ((((id) & 0x7) << 2) + 1))
  
  struct mtk_smi_larb_gen {
  	int port_in_larb[MTK_LARB_NR_MAX + 1];
  	void (*config_port)(struct device *);
  };

  
  struct mtk_smi {

  	struct device			*dev;
  	struct clk			*clk_apb, *clk_smi;
  	struct clk			*clk_async; /*only needed by mt2701*/
  	void __iomem			*smi_ao_base;

  };
  
  struct mtk_smi_larb { /* larb: local arbiter */

  	struct mtk_smi			smi;
  	void __iomem			*base;
  	struct device			*smi_common_dev;
  	const struct mtk_smi_larb_gen	*larb_gen;
  	int				larbid;
  	u32				*mmu;
  };
  
  enum mtk_smi_gen {
  	MTK_SMI_GEN1,
  	MTK_SMI_GEN2

  };
  
  static int mtk_smi_enable(const struct mtk_smi *smi)
  {
  	int ret;
  
  	ret = pm_runtime_get_sync(smi->dev);
  	if (ret < 0)
  		return ret;
  
  	ret = clk_prepare_enable(smi->clk_apb);
  	if (ret)
  		goto err_put_pm;
  
  	ret = clk_prepare_enable(smi->clk_smi);
  	if (ret)
  		goto err_disable_apb;
  
  	return 0;
  
  err_disable_apb:
  	clk_disable_unprepare(smi->clk_apb);
  err_put_pm:
  	pm_runtime_put_sync(smi->dev);
  	return ret;
  }
  
  static void mtk_smi_disable(const struct mtk_smi *smi)
  {
  	clk_disable_unprepare(smi->clk_smi);
  	clk_disable_unprepare(smi->clk_apb);
  	pm_runtime_put_sync(smi->dev);
  }
  
  int mtk_smi_larb_get(struct device *larbdev)
  {
  	struct mtk_smi_larb *larb = dev_get_drvdata(larbdev);

  	const struct mtk_smi_larb_gen *larb_gen = larb->larb_gen;

  	struct mtk_smi *common = dev_get_drvdata(larb->smi_common_dev);
  	int ret;
  
  	/* Enable the smi-common's power and clocks */
  	ret = mtk_smi_enable(common);
  	if (ret)
  		return ret;
  
  	/* Enable the larb's power and clocks */
  	ret = mtk_smi_enable(&larb->smi);
  	if (ret) {
  		mtk_smi_disable(common);
  		return ret;
  	}
  
  	/* Configure the iommu info for this larb */

  	larb_gen->config_port(larbdev);

  
  	return 0;
  }

  EXPORT_SYMBOL_GPL(mtk_smi_larb_get);

  
  void mtk_smi_larb_put(struct device *larbdev)
  {
  	struct mtk_smi_larb *larb = dev_get_drvdata(larbdev);
  	struct mtk_smi *common = dev_get_drvdata(larb->smi_common_dev);
  
  	/*
  	 * Don't de-configure the iommu info for this larb since there may be
  	 * several modules in this larb.
  	 * The iommu info will be reset after power off.
  	 */
  
  	mtk_smi_disable(&larb->smi);
  	mtk_smi_disable(common);
  }

  EXPORT_SYMBOL_GPL(mtk_smi_larb_put);

  
  static int
  mtk_smi_larb_bind(struct device *dev, struct device *master, void *data)
  {
  	struct mtk_smi_larb *larb = dev_get_drvdata(dev);
  	struct mtk_smi_iommu *smi_iommu = data;
  	unsigned int         i;
  
  	for (i = 0; i < smi_iommu->larb_nr; i++) {
  		if (dev == smi_iommu->larb_imu[i].dev) {
  			/* The 'mmu' may be updated in iommu-attach/detach. */
  			larb->mmu = &smi_iommu->larb_imu[i].mmu;
  			return 0;
  		}
  	}
  	return -ENODEV;
  }

  static void mtk_smi_larb_config_port(struct device *dev)
  {
  	struct mtk_smi_larb *larb = dev_get_drvdata(dev);
  
  	writel(*larb->mmu, larb->base + SMI_LARB_MMU_EN);
  }
  
  
  static void mtk_smi_larb_config_port_gen1(struct device *dev)
  {
  	struct mtk_smi_larb *larb = dev_get_drvdata(dev);
  	const struct mtk_smi_larb_gen *larb_gen = larb->larb_gen;
  	struct mtk_smi *common = dev_get_drvdata(larb->smi_common_dev);
  	int i, m4u_port_id, larb_port_num;
  	u32 sec_con_val, reg_val;
  
  	m4u_port_id = larb_gen->port_in_larb[larb->larbid];
  	larb_port_num = larb_gen->port_in_larb[larb->larbid + 1]
  			- larb_gen->port_in_larb[larb->larbid];
  
  	for (i = 0; i < larb_port_num; i++, m4u_port_id++) {
  		if (*larb->mmu & BIT(i)) {
  			/* bit[port + 3] controls the virtual or physical */
  			sec_con_val = SMI_SECUR_CON_VAL_VIRT(m4u_port_id);
  		} else {
  			/* do not need to enable m4u for this port */
  			continue;
  		}
  		reg_val = readl(common->smi_ao_base
  			+ REG_SMI_SECUR_CON_ADDR(m4u_port_id));
  		reg_val &= SMI_SECUR_CON_VAL_MSK(m4u_port_id);
  		reg_val |= sec_con_val;
  		reg_val |= SMI_SECUR_CON_VAL_DOMAIN(m4u_port_id);
  		writel(reg_val,
  			common->smi_ao_base
  			+ REG_SMI_SECUR_CON_ADDR(m4u_port_id));
  	}
  }

  static void
  mtk_smi_larb_unbind(struct device *dev, struct device *master, void *data)
  {
  	/* Do nothing as the iommu is always enabled. */
  }
  
  static const struct component_ops mtk_smi_larb_component_ops = {
  	.bind = mtk_smi_larb_bind,
  	.unbind = mtk_smi_larb_unbind,
  };

  static const struct mtk_smi_larb_gen mtk_smi_larb_mt8173 = {
  	/* mt8173 do not need the port in larb */
  	.config_port = mtk_smi_larb_config_port,
  };
  
  static const struct mtk_smi_larb_gen mtk_smi_larb_mt2701 = {
  	.port_in_larb = {
  		LARB0_PORT_OFFSET, LARB1_PORT_OFFSET,
  		LARB2_PORT_OFFSET, LARB3_PORT_OFFSET
  	},
  	.config_port = mtk_smi_larb_config_port_gen1,
  };
  
  static const struct of_device_id mtk_smi_larb_of_ids[] = {
  	{
  		.compatible = "mediatek,mt8173-smi-larb",
  		.data = &mtk_smi_larb_mt8173
  	},
  	{
  		.compatible = "mediatek,mt2701-smi-larb",
  		.data = &mtk_smi_larb_mt2701
  	},
  	{}
  };

  static int mtk_smi_larb_probe(struct platform_device *pdev)
  {
  	struct mtk_smi_larb *larb;
  	struct resource *res;
  	struct device *dev = &pdev->dev;
  	struct device_node *smi_node;
  	struct platform_device *smi_pdev;

  	const struct of_device_id *of_id;

  
  	if (!dev->pm_domain)
  		return -EPROBE_DEFER;

  	of_id = of_match_node(mtk_smi_larb_of_ids, pdev->dev.of_node);
  	if (!of_id)
  		return -EINVAL;

  	larb = devm_kzalloc(dev, sizeof(*larb), GFP_KERNEL);
  	if (!larb)
  		return -ENOMEM;

  	larb->larb_gen = of_id->data;

  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  	larb->base = devm_ioremap_resource(dev, res);
  	if (IS_ERR(larb->base))
  		return PTR_ERR(larb->base);
  
  	larb->smi.clk_apb = devm_clk_get(dev, "apb");
  	if (IS_ERR(larb->smi.clk_apb))
  		return PTR_ERR(larb->smi.clk_apb);
  
  	larb->smi.clk_smi = devm_clk_get(dev, "smi");
  	if (IS_ERR(larb->smi.clk_smi))
  		return PTR_ERR(larb->smi.clk_smi);
  	larb->smi.dev = dev;
  
  	smi_node = of_parse_phandle(dev->of_node, "mediatek,smi", 0);
  	if (!smi_node)
  		return -EINVAL;
  
  	smi_pdev = of_find_device_by_node(smi_node);
  	of_node_put(smi_node);
  	if (smi_pdev) {
  		larb->smi_common_dev = &smi_pdev->dev;
  	} else {
  		dev_err(dev, "Failed to get the smi_common device
  ");
  		return -EINVAL;
  	}
  
  	pm_runtime_enable(dev);
  	platform_set_drvdata(pdev, larb);
  	return component_add(dev, &mtk_smi_larb_component_ops);
  }
  
  static int mtk_smi_larb_remove(struct platform_device *pdev)
  {
  	pm_runtime_disable(&pdev->dev);
  	component_del(&pdev->dev, &mtk_smi_larb_component_ops);
  	return 0;
  }

  static struct platform_driver mtk_smi_larb_driver = {
  	.probe	= mtk_smi_larb_probe,

  	.remove	= mtk_smi_larb_remove,

  	.driver	= {
  		.name = "mtk-smi-larb",
  		.of_match_table = mtk_smi_larb_of_ids,
  	}
  };

  static const struct of_device_id mtk_smi_common_of_ids[] = {
  	{
  		.compatible = "mediatek,mt8173-smi-common",
  		.data = (void *)MTK_SMI_GEN2
  	},
  	{
  		.compatible = "mediatek,mt2701-smi-common",
  		.data = (void *)MTK_SMI_GEN1
  	},
  	{}
  };

  static int mtk_smi_common_probe(struct platform_device *pdev)
  {
  	struct device *dev = &pdev->dev;
  	struct mtk_smi *common;

  	struct resource *res;
  	const struct of_device_id *of_id;
  	enum mtk_smi_gen smi_gen;

  
  	if (!dev->pm_domain)
  		return -EPROBE_DEFER;
  
  	common = devm_kzalloc(dev, sizeof(*common), GFP_KERNEL);
  	if (!common)
  		return -ENOMEM;
  	common->dev = dev;
  
  	common->clk_apb = devm_clk_get(dev, "apb");
  	if (IS_ERR(common->clk_apb))
  		return PTR_ERR(common->clk_apb);
  
  	common->clk_smi = devm_clk_get(dev, "smi");
  	if (IS_ERR(common->clk_smi))
  		return PTR_ERR(common->clk_smi);

  	of_id = of_match_node(mtk_smi_common_of_ids, pdev->dev.of_node);
  	if (!of_id)
  		return -EINVAL;
  
  	/*
  	 * for mtk smi gen 1, we need to get the ao(always on) base to config
  	 * m4u port, and we need to enable the aync clock for transform the smi
  	 * clock into emi clock domain, but for mtk smi gen2, there's no smi ao
  	 * base.
  	 */
  	smi_gen = (enum mtk_smi_gen)of_id->data;
  	if (smi_gen == MTK_SMI_GEN1) {
  		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  		common->smi_ao_base = devm_ioremap_resource(dev, res);
  		if (IS_ERR(common->smi_ao_base))
  			return PTR_ERR(common->smi_ao_base);
  
  		common->clk_async = devm_clk_get(dev, "async");
  		if (IS_ERR(common->clk_async))
  			return PTR_ERR(common->clk_async);
  
  		clk_prepare_enable(common->clk_async);
  	}

  	pm_runtime_enable(dev);
  	platform_set_drvdata(pdev, common);
  	return 0;
  }
  
  static int mtk_smi_common_remove(struct platform_device *pdev)
  {
  	pm_runtime_disable(&pdev->dev);
  	return 0;
  }

  static struct platform_driver mtk_smi_common_driver = {
  	.probe	= mtk_smi_common_probe,
  	.remove = mtk_smi_common_remove,
  	.driver	= {
  		.name = "mtk-smi-common",
  		.of_match_table = mtk_smi_common_of_ids,
  	}
  };
  
  static int __init mtk_smi_init(void)
  {
  	int ret;
  
  	ret = platform_driver_register(&mtk_smi_common_driver);
  	if (ret != 0) {
  		pr_err("Failed to register SMI driver
  ");
  		return ret;
  	}
  
  	ret = platform_driver_register(&mtk_smi_larb_driver);
  	if (ret != 0) {
  		pr_err("Failed to register SMI-LARB driver
  ");
  		goto err_unreg_smi;
  	}
  	return ret;
  
  err_unreg_smi:
  	platform_driver_unregister(&mtk_smi_common_driver);
  	return ret;
  }

  subsys_initcall(mtk_smi_init);