[PATCH v6 3/5] memory: mediatek: Add SMI driver
Matthias Brugger
matthias.bgg at gmail.com
Mon Dec 14 10:18:41 PST 2015
On Tuesday 08 Dec 2015 17:49:11 Yong Wu wrote:
> This patch add SMI(Smart Multimedia Interface) driver. This driver
> is responsible to enable/disable iommu and control the power domain
> and clocks of each local arbiter.
>
> Signed-off-by: Yong Wu <yong.wu at mediatek.com>
> ---
> Currently SMI offer mtk_smi_larb_get/put to enable the power-domain
> ,clocks and initialize the iommu configuration register for each a local
> arbiter, The reason is:
> a) If a device would like to disable iommu, it also need call
> mtk_smi_larb_get/put to enable its power and clocks.
> b) The iommu core don't support attach/detach a device within a
> iommu-group. So we cann't use iommu_attach_device(iommu_detach_device)
> instead
> of mtk_smi_larb_get/put.
>
> drivers/memory/Kconfig | 8 ++
> drivers/memory/Makefile | 1 +
> drivers/memory/mtk-smi.c | 297
> +++++++++++++++++++++++++++++++++++++++++++++ include/soc/mediatek/smi.h |
> 53 ++++++++
> 4 files changed, 359 insertions(+)
> create mode 100644 drivers/memory/mtk-smi.c
> create mode 100644 include/soc/mediatek/smi.h
>
> diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
> index 6f31546..51d5cd2 100644
> --- a/drivers/memory/Kconfig
> +++ b/drivers/memory/Kconfig
> @@ -114,6 +114,14 @@ config JZ4780_NEMC
> the Ingenic JZ4780. This controller is used to handle external
> memory devices such as NAND and SRAM.
>
> +config MTK_SMI
> + bool
> + depends on ARCH_MEDIATEK || COMPILE_TEST
> + help
> + This driver is for the Memory Controller module in MediaTek SoCs,
> + mainly help enable/disable iommu and control the power domain and
> + clocks for each local arbiter.
> +
> source "drivers/memory/tegra/Kconfig"
>
> endif
> diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
> index 1c46af5..890bdf4 100644
> --- a/drivers/memory/Makefile
> +++ b/drivers/memory/Makefile
> @@ -15,5 +15,6 @@ obj-$(CONFIG_FSL_IFC) += fsl_ifc.o
> obj-$(CONFIG_MVEBU_DEVBUS) += mvebu-devbus.o
> obj-$(CONFIG_TEGRA20_MC) += tegra20-mc.o
> obj-$(CONFIG_JZ4780_NEMC) += jz4780-nemc.o
> +obj-$(CONFIG_MTK_SMI) += mtk-smi.o
>
> obj-$(CONFIG_TEGRA_MC) += tegra/
> diff --git a/drivers/memory/mtk-smi.c b/drivers/memory/mtk-smi.c
> new file mode 100644
> index 0000000..3562081
> --- /dev/null
> +++ b/drivers/memory/mtk-smi.c
> @@ -0,0 +1,297 @@
> +/*
> + * Copyright (c) 2014-2015 MediaTek Inc.
> + * Author: Yong Wu <yong.wu at 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/err.h>
> +#include <linux/io.h>
> +#include <linux/of_address.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
> +#define F_SMI_MMU_EN(port) BIT(port)
> +
> +struct mtk_smi_common {
> + struct device *dev;
> + struct clk *clk_apb, *clk_smi;
> +};
> +
> +struct mtk_smi_larb { /* larb: local arbiter */
> + struct device *dev;
> + void __iomem *base;
> + struct clk *clk_apb, *clk_smi;
> + struct device *smi_common_dev;
> + u32 mmu;
> +};
> +
> +static int
> +mtk_smi_enable(struct device *dev, struct clk *apb, struct clk *smi)
> +{
> + int ret;
> +
> + ret = pm_runtime_get_sync(dev);
> + if (ret < 0)
> + return ret;
> +
> + ret = clk_prepare_enable(apb);
> + if (ret)
> + goto err_put_pm;
> +
> + ret = clk_prepare_enable(smi);
> + if (ret)
> + goto err_disable_apb;
> +
> + return 0;
> +
> +err_disable_apb:
> + clk_disable_unprepare(apb);
> +err_put_pm:
> + pm_runtime_put_sync(dev);
> + return ret;
> +}
> +
> +static void
> +mtk_smi_disable(struct device *dev, struct clk *apb, struct clk *smi)
> +{
> + clk_disable_unprepare(smi);
> + clk_disable_unprepare(apb);
> + pm_runtime_put_sync(dev);
> +}
> +
> +static int mtk_smi_common_enable(struct mtk_smi_common *common)
> +{
> + return mtk_smi_enable(common->dev, common->clk_apb, common->clk_smi);
> +}
> +
> +static void mtk_smi_common_disable(struct mtk_smi_common *common)
> +{
> + mtk_smi_disable(common->dev, common->clk_apb, common->clk_smi);
> +}
> +
> +static int mtk_smi_larb_enable(struct mtk_smi_larb *larb)
> +{
> + return mtk_smi_enable(larb->dev, larb->clk_apb, larb->clk_smi);
> +}
> +
> +static void mtk_smi_larb_disable(struct mtk_smi_larb *larb)
> +{
> + mtk_smi_disable(larb->dev, larb->clk_apb, larb->clk_smi);
> +}
> +
This is somehow over-engineered. Just use mtk_smi_enable and mtk_smi_disable
instead of adding an extra indirection.
> +int mtk_smi_larb_get(struct device *larbdev)
> +{
> + struct mtk_smi_larb *larb = dev_get_drvdata(larbdev);
> + struct mtk_smi_common *common = dev_get_drvdata(larb->smi_common_dev);
> + int ret;
> +
> + ret = mtk_smi_common_enable(common);
> + if (ret)
> + return ret;
> +
> + ret = mtk_smi_larb_enable(larb);
> + if (ret)
> + goto err_put_smi;
> +
> + /* Configure the iommu info */
> + writel_relaxed(larb->mmu, larb->base + SMI_LARB_MMU_EN);
> +
> + return 0;
> +
> +err_put_smi:
> + mtk_smi_common_disable(common);
> + return ret;
> +}
> +
> +void mtk_smi_larb_put(struct device *larbdev)
> +{
> + struct mtk_smi_larb *larb = dev_get_drvdata(larbdev);
> + struct mtk_smi_common *common = dev_get_drvdata(larb->smi_common_dev);
> +
> + writel_relaxed(0, larb->base + SMI_LARB_MMU_EN);
> + mtk_smi_larb_disable(larb);
> + mtk_smi_common_disable(common);
> +}
> +
Looks strange that you just disable all MMUs while you only enable some of
them at runtime. Unfortunately the datasheet I have lacks the SMI part, so I
can just guess how the HW is working.
>From the DTS it looks like as if a larb can be used by two different
components (e.g. larb0 from ovl0 and rdma0). Wouldn't that produce a conflict?
Regards,
Matthias
> +void mtk_smi_config_port(struct device *larbdev, unsigned int larbportid,
> + bool enable)
> +{
> + struct mtk_smi_larb *larb = dev_get_drvdata(larbdev);
> +
> + dev_dbg(larbdev, "%s iommu port: %d\n",
> + enable ? "enable" : "disable", larbportid);
> +
> + /*
> + * Only record the iommu info here,
> + * and it will work after its power and clocks is enabled.
> + */
> + if (enable)
> + larb->mmu |= F_SMI_MMU_EN(larbportid);
> + else
> + larb->mmu &= ~F_SMI_MMU_EN(larbportid);
> +}
> +
> +static int
> +mtk_smi_larb_bind(struct device *dev, struct device *master, void *data)
> +{
> + return 0;
> +}
> +
> +static void
> +mtk_smi_larb_unbind(struct device *dev, struct device *master, void *data)
> +{
> +}
> +
> +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;
> + larb->dev = dev;
> +
> + 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->clk_apb = devm_clk_get(dev, "apb");
> + if (IS_ERR(larb->clk_apb))
> + return PTR_ERR(larb->clk_apb);
> +
> + larb->clk_smi = devm_clk_get(dev, "smi");
> + if (IS_ERR(larb->clk_smi))
> + return PTR_ERR(larb->clk_smi);
> +
> + 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);
> + dev_set_drvdata(dev, 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 *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);
> + dev_set_drvdata(dev, 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);
> diff --git a/include/soc/mediatek/smi.h b/include/soc/mediatek/smi.h
> new file mode 100644
> index 0000000..6f41b2e
> --- /dev/null
> +++ b/include/soc/mediatek/smi.h
> @@ -0,0 +1,53 @@
> +/*
> + * Copyright (c) 2014-2015 MediaTek Inc.
> + * Author: Yong Wu <yong.wu at 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.
> + */
> +#ifndef MTK_IOMMU_SMI_H
> +#define MTK_IOMMU_SMI_H
> +
> +#include <linux/device.h>
> +
> +#ifdef CONFIG_MTK_SMI
> +
> +/*
> + * Record the iommu info for each port in the local arbiter.
> + * It's only for iommu.
> + */
> +void mtk_smi_config_port(struct device *larbdev, unsigned int larbportid,
> + bool enable);
> +/*
> + * mtk_smi_larb_get: Enable the power domain and clocks for this local
> arbiter. + * It also initialize some basic setting(like
> iommu). + * mtk_smi_larb_put: Disable the power domain and clocks for this
> local arbiter. + * Both should be called in non-atomic context.
> + *
> + * Returns 0 if successful, negative on failure.
> + */
> +int mtk_smi_larb_get(struct device *larbdev);
> +void mtk_smi_larb_put(struct device *larbdev);
> +
> +#else
> +
> +static inline void
> +mtk_smi_config_port(struct device *larbdev, unsigned int larbportid,
> + bool enable) { }
> +
> +static inline int mtk_smi_larb_get(struct device *larbdev)
> +{
> + return 0;
> +}
> +
> +static inline void mtk_smi_larb_put(struct device *larbdev) { }
> +
> +#endif
> +
> +#endif
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