diff options
Diffstat (limited to 'drivers/memory/mtk-smi.c')
| -rw-r--r-- | drivers/memory/mtk-smi.c | 273 |
1 files changed, 273 insertions, 0 deletions
diff --git a/drivers/memory/mtk-smi.c b/drivers/memory/mtk-smi.c new file mode 100644 index 000000000..089091f5f --- /dev/null +++ b/drivers/memory/mtk-smi.c @@ -0,0 +1,273 @@ +/* + * 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> + +#define SMI_LARB_MMU_EN 0xf00 + +struct mtk_smi { + struct device *dev; + struct clk *clk_apb, *clk_smi; +}; + +struct mtk_smi_larb { /* larb: local arbiter */ + struct mtk_smi smi; + void __iomem *base; + struct device *smi_common_dev; + u32 *mmu; +}; + +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); + 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 */ + writel(*larb->mmu, larb->base + SMI_LARB_MMU_EN); + + return 0; +} + +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); +} + +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_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 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; + + if (!dev->pm_domain) + return -EPROBE_DEFER; + + larb = devm_kzalloc(dev, sizeof(*larb), GFP_KERNEL); + if (!larb) + return -ENOMEM; + + 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\n"); + 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 const struct of_device_id mtk_smi_larb_of_ids[] = { + { .compatible = "mediatek,mt8173-smi-larb",}, + {} +}; + +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 int mtk_smi_common_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct mtk_smi *common; + + 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); + + 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 const struct of_device_id mtk_smi_common_of_ids[] = { + { .compatible = "mediatek,mt8173-smi-common", }, + {} +}; + +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\n"); + return ret; + } + + ret = platform_driver_register(&mtk_smi_larb_driver); + if (ret != 0) { + pr_err("Failed to register SMI-LARB driver\n"); + goto err_unreg_smi; + } + return ret; + +err_unreg_smi: + platform_driver_unregister(&mtk_smi_common_driver); + return ret; +} +subsys_initcall(mtk_smi_init); |