diff mbox series

[1/2] memory/mediatek: Add an interface to get current DDR data rate

Message ID 20241212090029.13692-2-crystal.guo@mediatek.com (mailing list archive)
State New
Headers show
Series Add MediaTek DRAMC driver support | expand

Commit Message

Crystal Guo Dec. 12, 2024, 8:59 a.m. UTC 
Add MediaTek DRAMC driver to provide an interface that can
obtain current DDR data rate.

Signed-off-by: Crystal Guo <crystal.guo@mediatek.com>
---
 drivers/memory/Kconfig                 |   1 +
 drivers/memory/Makefile                |   1 +
 drivers/memory/mediatek/Kconfig        |  21 ++
 drivers/memory/mediatek/Makefile       |   2 +
 drivers/memory/mediatek/mtk-dramc.c    | 325 +++++++++++++++++++++++++
 include/linux/soc/mediatek/mtk-dramc.h |  41 ++++
 6 files changed, 391 insertions(+)
 create mode 100644 drivers/memory/mediatek/Kconfig
 create mode 100644 drivers/memory/mediatek/Makefile
 create mode 100644 drivers/memory/mediatek/mtk-dramc.c
 create mode 100644 include/linux/soc/mediatek/mtk-dramc.h

Comments

AngeloGioacchino Del Regno Dec. 12, 2024, 10:46 a.m. UTC | #1 
Il 12/12/24 09:59, Crystal Guo ha scritto:
> Add MediaTek DRAMC driver to provide an interface that can
> obtain current DDR data rate.
> 
> Signed-off-by: Crystal Guo <crystal.guo@mediatek.com>
> ---
>   drivers/memory/Kconfig                 |   1 +
>   drivers/memory/Makefile                |   1 +
>   drivers/memory/mediatek/Kconfig        |  21 ++
>   drivers/memory/mediatek/Makefile       |   2 +
>   drivers/memory/mediatek/mtk-dramc.c    | 325 +++++++++++++++++++++++++
>   include/linux/soc/mediatek/mtk-dramc.h |  41 ++++
>   6 files changed, 391 insertions(+)
>   create mode 100644 drivers/memory/mediatek/Kconfig
>   create mode 100644 drivers/memory/mediatek/Makefile
>   create mode 100644 drivers/memory/mediatek/mtk-dramc.c
>   create mode 100644 include/linux/soc/mediatek/mtk-dramc.h
> 
> diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
> index c82d8d8a16ea..b1698549ff81 100644
> --- a/drivers/memory/Kconfig
> +++ b/drivers/memory/Kconfig
> @@ -227,5 +227,6 @@ config STM32_FMC2_EBI
>   
>   source "drivers/memory/samsung/Kconfig"
>   source "drivers/memory/tegra/Kconfig"
> +source "drivers/memory/mediatek/Kconfig"
>   
>   endif
> diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
> index d2e6ca9abbe0..cf1091449d2e 100644
> --- a/drivers/memory/Makefile
> +++ b/drivers/memory/Makefile
> @@ -27,6 +27,7 @@ obj-$(CONFIG_STM32_FMC2_EBI)	+= stm32-fmc2-ebi.o
>   
>   obj-$(CONFIG_SAMSUNG_MC)	+= samsung/
>   obj-$(CONFIG_TEGRA_MC)		+= tegra/
> +obj-$(CONFIG_HAVE_MTK_MC)	+= mediatek/
>   obj-$(CONFIG_TI_EMIF_SRAM)	+= ti-emif-sram.o
>   obj-$(CONFIG_FPGA_DFL_EMIF)	+= dfl-emif.o
>   
> diff --git a/drivers/memory/mediatek/Kconfig b/drivers/memory/mediatek/Kconfig
> new file mode 100644
> index 000000000000..00764cdb157e
> --- /dev/null
> +++ b/drivers/memory/mediatek/Kconfig
> @@ -0,0 +1,21 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +config HAVE_MTK_MC
> +	bool "MediaTek Memory Controller support"
> +	help
> +	  This option allows to enable MediaTek memory controller drivers,
> +	  which may include controllers for DRAM or others.
> +	  Select Y here if you need support for MediaTek memory controller.
> +	  If you don't need, select N.
> +
> +if HAVE_MTK_MC
> +
> +config MTK_DRAMC
> +	tristate "MediaTek DRAMC driver"
> +	depends on HAVE_MTK_MC
> +	help
> +	  This option selects the MediaTek DRAMC driver, which provides
> +	  an interface for reporting the current data rate of DRAM.
> +	  Select Y here if you need support for the MediaTek DRAMC driver.
> +	  If you don't need, select N.
> +
> +endif
> diff --git a/drivers/memory/mediatek/Makefile b/drivers/memory/mediatek/Makefile
> new file mode 100644
> index 000000000000..a1395fc55b41
> --- /dev/null
> +++ b/drivers/memory/mediatek/Makefile
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0
> +obj-$(CONFIG_MTK_DRAMC)		+= mtk-dramc.o
> diff --git a/drivers/memory/mediatek/mtk-dramc.c b/drivers/memory/mediatek/mtk-dramc.c
> new file mode 100644
> index 000000000000..9c2c8e187a4a
> --- /dev/null
> +++ b/drivers/memory/mediatek/mtk-dramc.c
> @@ -0,0 +1,325 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2024 MediaTek Inc.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/device.h>
> +#include <linux/platform_device.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/printk.h>
> +#include <linux/io.h>
> +#include <linux/soc/mediatek/mtk-dramc.h>
> +
> +static struct platform_device *dramc_pdev;
> +static struct platform_driver dramc_drv;

You don't need these globals.

> +
> +static int fmeter_init(struct platform_device *pdev,
> +		       struct fmeter_dev_t *fmeter_dev_ptr, unsigned int fmeter_version)
> +{
> +	struct device_node *dramc_node = pdev->dev.of_node;
> +	int ret;
> +
> +	ret = of_property_read_u32(dramc_node,
> +				   "crystal-freq", &(fmeter_dev_ptr->crystal_freq));
> +	ret |= of_property_read_u32(dramc_node,
> +				    "shu-of", &(fmeter_dev_ptr->shu_of));

ret |= x doesn't make sense.

ret = ...
if (ret)
	return ret;

> +	ret |= of_property_read_u32_array(dramc_node,
> +					  "shu-lv", (unsigned int *)&(fmeter_dev_ptr->shu_lv), 3);
> +	ret |= of_property_read_u32_array(dramc_node,
> +					  "pll-id", (unsigned int *)&(fmeter_dev_ptr->pll_id), 3);
> +	ret |= of_property_read_u32_array(dramc_node,
> +					  "sdmpcw", (unsigned int *)(fmeter_dev_ptr->sdmpcw), 6);
> +	ret |= of_property_read_u32_array(dramc_node,
> +					  "posdiv", (unsigned int *)(fmeter_dev_ptr->posdiv), 6);
> +	ret |= of_property_read_u32_array(dramc_node,
> +					  "fbksel", (unsigned int *)(fmeter_dev_ptr->fbksel), 6);
> +	ret |= of_property_read_u32_array(dramc_node,
> +					  "dqsopen", (unsigned int *)(fmeter_dev_ptr->dqsopen), 6);
> +	if (fmeter_version == 1) {
> +		fmeter_dev_ptr->version = 1;
> +		ret |= of_property_read_u32_array(dramc_node,
> +			"async-ca", (unsigned int *)(fmeter_dev_ptr->async_ca), 6);
> +		ret |= of_property_read_u32_array(dramc_node,
> +			"dq-ser-mode", (unsigned int *)(fmeter_dev_ptr->dq_ser_mode), 6);
> +	}
> +	return ret;
> +}
> +
> +static ssize_t dram_data_rate_show(struct device_driver *driver, char *buf)
> +{
> +	return snprintf(buf, PAGE_SIZE, "DRAM data rate = %d\n",
> +		mtk_dramc_get_data_rate());
> +}
> +
> +static DRIVER_ATTR_RO(dram_data_rate);> +
> +static int dramc_probe(struct platform_device *pdev)
> +{
> +	struct device_node *dramc_node = pdev->dev.of_node;
> +	struct dramc_dev_t *dramc_dev_ptr;
> +	unsigned int fmeter_version;
> +	struct resource *res;
> +	unsigned int i, size;
> +	int ret;
> +
> +	pr_info("%s: module probe.\n", __func__);

This pr_info makes no sense. Please remove.

> +	dramc_pdev = pdev;
> +	dramc_dev_ptr = devm_kmalloc(&pdev->dev,
> +				     sizeof(struct dramc_dev_t), GFP_KERNEL);
> +
> +	if (!dramc_dev_ptr)
> +		return -ENOMEM;
> +
> +	ret = of_property_read_u32(dramc_node,
> +				   "support-ch-cnt", &dramc_dev_ptr->support_ch_cnt);
> +	if (ret) {
> +		pr_info("%s: get support_ch_cnt fail\n", __func__);

that's an error, and you want dev_err_probe().

> +		return -EINVAL;
> +	}
> +
> +	dramc_dev_ptr->sleep_base = of_iomap(dramc_node,
> +					     dramc_dev_ptr->support_ch_cnt * 4);
> +	if (IS_ERR(dramc_dev_ptr->sleep_base)) {
> +		pr_info("%s: unable to map sleep base\n", __func__);

same, here and everywhere else

> +		return -EINVAL;
> +	}
> +
> +	size = sizeof(phys_addr_t) * dramc_dev_ptr->support_ch_cnt;
> +	dramc_dev_ptr->dramc_chn_base_ao = devm_kmalloc(&pdev->dev,
> +							size, GFP_KERNEL);
> +	if (!(dramc_dev_ptr->dramc_chn_base_ao))
> +		return -ENOMEM;
> +	dramc_dev_ptr->dramc_chn_base_nao = devm_kmalloc(&pdev->dev,
> +							 size, GFP_KERNEL);
> +	if (!(dramc_dev_ptr->dramc_chn_base_nao))
> +		return -ENOMEM;
> +	dramc_dev_ptr->ddrphy_chn_base_ao = devm_kmalloc(&pdev->dev,
> +							 size, GFP_KERNEL);
> +	if (!(dramc_dev_ptr->ddrphy_chn_base_ao))
> +		return -ENOMEM;
> +	dramc_dev_ptr->ddrphy_chn_base_nao = devm_kmalloc(&pdev->dev,
> +							  size, GFP_KERNEL);
> +	if (!(dramc_dev_ptr->ddrphy_chn_base_nao))
> +		return -ENOMEM;
> +
> +	for (i = 0; i < dramc_dev_ptr->support_ch_cnt; i++) {
> +		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
> +		dramc_dev_ptr->dramc_chn_base_ao[i] =
> +			devm_ioremap_resource(&pdev->dev, res);
> +		if (IS_ERR(dramc_dev_ptr->dramc_chn_base_ao[i])) {
> +			pr_info("%s: unable to map ch%d DRAMC AO base\n",
> +				__func__, i);
> +			return -EINVAL;
> +		}
> +
> +		res = platform_get_resource(pdev, IORESOURCE_MEM,
> +					    i + dramc_dev_ptr->support_ch_cnt);
> +		dramc_dev_ptr->dramc_chn_base_nao[i] =
> +			devm_ioremap_resource(&pdev->dev, res);
> +		if (IS_ERR(dramc_dev_ptr->dramc_chn_base_nao[i])) {
> +			pr_info("%s: unable to map ch%d DRAMC NAO base\n",
> +				__func__, i);
> +			return -EINVAL;
> +		}
> +
> +		res = platform_get_resource(pdev, IORESOURCE_MEM,
> +					    i + dramc_dev_ptr->support_ch_cnt * 2);
> +		dramc_dev_ptr->ddrphy_chn_base_ao[i] =
> +			devm_ioremap_resource(&pdev->dev, res);
> +		if (IS_ERR(dramc_dev_ptr->ddrphy_chn_base_ao[i])) {
> +			pr_info("%s: unable to map ch%d DDRPHY AO base\n",
> +				__func__, i);
> +			return -EINVAL;
> +		}
> +
> +		res = platform_get_resource(pdev, IORESOURCE_MEM,
> +					    i + dramc_dev_ptr->support_ch_cnt * 3);
> +		dramc_dev_ptr->ddrphy_chn_base_nao[i] =
> +			devm_ioremap_resource(&pdev->dev, res);
> +		if (IS_ERR(dramc_dev_ptr->ddrphy_chn_base_nao[i])) {
> +			pr_info("%s: unable to map ch%d DDRPHY NAO base\n",
> +				__func__, i);
> +			return -EINVAL;
> +		}
> +	}
> +
> +	ret = of_property_read_u32(dramc_node, "fmeter-version", &fmeter_version);

This is something for platform data, not devicetree.

> +	if (ret) {
> +		pr_info("%s: get fmeter_version fail\n", __func__);
> +		return -EINVAL;
> +	}
> +	pr_info("%s: fmeter_version(%d)\n", __func__, fmeter_version);
> +
> +	if (fmeter_version == 1) {
> +		dramc_dev_ptr->fmeter_dev_ptr = devm_kmalloc(&pdev->dev,
> +							     sizeof(struct fmeter_dev_t),
> +							     GFP_KERNEL);
> +		if (!(dramc_dev_ptr->fmeter_dev_ptr)) {
> +			pr_info("%s: memory  alloc fail\n", __func__);
> +			return -ENOMEM;
> +		}
> +		ret = fmeter_init(pdev, dramc_dev_ptr->fmeter_dev_ptr, fmeter_version);
> +		if (ret) {
> +			pr_info("%s: fmeter_init fail\n", __func__);
> +			return -EINVAL;
> +		}
> +	} else {
> +		dramc_dev_ptr->fmeter_dev_ptr = NULL;
> +	}
> +	ret = driver_create_file(pdev->dev.driver, &driver_attr_dram_data_rate);
> +	if (ret) {
> +		pr_info("%s: fail to create dram_data_rate sysfs\n", __func__);
> +		return ret;
> +	}
> +
> +	platform_set_drvdata(pdev, dramc_dev_ptr);
> +	pr_info("%s: DRAM data rate = %d\n", __func__,
> +		mtk_dramc_get_data_rate());
> +
> +	return ret;
> +}
> +
> +static unsigned int fmeter_v1(struct dramc_dev_t *dramc_dev_ptr)
> +{
> +	struct fmeter_dev_t *fmeter_dev_ptr =
> +		(struct fmeter_dev_t *)dramc_dev_ptr->fmeter_dev_ptr;
> +	unsigned int shu_lv_val;
> +	unsigned int pll_id_val;
> +	unsigned int sdmpcw_val;
> +	unsigned int posdiv_val;
> +	unsigned int ckdiv4_val;
> +	unsigned int offset;
> +	unsigned int vco_freq;
> +	unsigned int fbksel;
> +	unsigned int dqsopen;
> +	unsigned int async_ca;
> +	unsigned int dq_ser_mode;
> +
> +	shu_lv_val = (readl(dramc_dev_ptr->ddrphy_chn_base_ao[0] +
> +		fmeter_dev_ptr->shu_lv.offset) &
> +		fmeter_dev_ptr->shu_lv.mask) >>
> +		fmeter_dev_ptr->shu_lv.shift;
> +
> +	pll_id_val = (readl(dramc_dev_ptr->ddrphy_chn_base_ao[0] +
> +		fmeter_dev_ptr->pll_id.offset) &
> +		fmeter_dev_ptr->pll_id.mask) >>
> +		fmeter_dev_ptr->pll_id.shift;
> +
> +	offset = fmeter_dev_ptr->sdmpcw[pll_id_val].offset +
> +		fmeter_dev_ptr->shu_of * shu_lv_val;
> +	sdmpcw_val = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
> +		fmeter_dev_ptr->sdmpcw[pll_id_val].mask) >>
> +		fmeter_dev_ptr->sdmpcw[pll_id_val].shift;
> +
> +	offset = fmeter_dev_ptr->posdiv[pll_id_val].offset +
> +		fmeter_dev_ptr->shu_of * shu_lv_val;
> +	posdiv_val = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
> +		fmeter_dev_ptr->posdiv[pll_id_val].mask) >>
> +		fmeter_dev_ptr->posdiv[pll_id_val].shift;
> +
> +	offset = fmeter_dev_ptr->fbksel[pll_id_val].offset +
> +		fmeter_dev_ptr->shu_of * shu_lv_val;
> +	fbksel = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
> +		fmeter_dev_ptr->fbksel[pll_id_val].mask) >>
> +		fmeter_dev_ptr->fbksel[pll_id_val].shift;
> +
> +	offset = fmeter_dev_ptr->dqsopen[pll_id_val].offset +
> +		fmeter_dev_ptr->shu_of * shu_lv_val;
> +	dqsopen = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
> +		fmeter_dev_ptr->dqsopen[pll_id_val].mask) >>
> +		fmeter_dev_ptr->dqsopen[pll_id_val].shift;
> +
> +	offset = fmeter_dev_ptr->async_ca[pll_id_val].offset +
> +		fmeter_dev_ptr->shu_of * shu_lv_val;
> +	async_ca = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
> +		fmeter_dev_ptr->async_ca[pll_id_val].mask) >>
> +		fmeter_dev_ptr->async_ca[pll_id_val].shift;
> +
> +	offset = fmeter_dev_ptr->dq_ser_mode[pll_id_val].offset +
> +		fmeter_dev_ptr->shu_of * shu_lv_val;
> +	dq_ser_mode = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
> +		fmeter_dev_ptr->dq_ser_mode[pll_id_val].mask) >>
> +		fmeter_dev_ptr->dq_ser_mode[pll_id_val].shift;
> +	ckdiv4_val = (dq_ser_mode == 1); // 1: DIV4, 2: DIV8, 3: DIV16
> +
> +	posdiv_val &= ~(0x4);
> +
> +	vco_freq = ((fmeter_dev_ptr->crystal_freq) *
> +		(sdmpcw_val >> 7)) >> posdiv_val >> 1 >> ckdiv4_val
> +		<< fbksel;

That vco_freq calculation is seriously unreadable :\

> +
> +	if ((dqsopen == 1) && (async_ca == 1))
> +		vco_freq >>= 1;
> +
> +	return vco_freq;
> +}
> +
> +/*
> + * mtk_dramc_get_data_rate - calculate DRAM data rate
> + *
> + * Returns DRAM data rate (MB/s)
> + */
> +unsigned int mtk_dramc_get_data_rate(void)
> +{
> +	struct dramc_dev_t *dramc_dev_ptr;
> +	struct fmeter_dev_t *fmeter_dev_ptr;
> +
> +	if (!dramc_pdev)
> +		return 0;
> +
> +	dramc_dev_ptr =
> +		(struct dramc_dev_t *)platform_get_drvdata(dramc_pdev);
> +
> +	fmeter_dev_ptr = (struct fmeter_dev_t *)dramc_dev_ptr->fmeter_dev_ptr;
> +	if (!fmeter_dev_ptr)
> +		return 0;
> +
> +	if (fmeter_dev_ptr->version == 1)
> +		return fmeter_v1(dramc_dev_ptr);
> +	return 0;
> +}
> +EXPORT_SYMBOL(mtk_dramc_get_data_rate);

Not sure about mtk_dramc_get_data_rate().

Please show an example of how you're actually using it in the external driver,
as there are many ways to expose this value.

> +
> +static int dramc_remove(struct platform_device *pdev)
> +{
> +	dramc_pdev = NULL;
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id dramc_of_ids[] = {
> +	{.compatible = "mediatek,common-dramc",},

{ .compatible = "mediatek,something" },
{ /* sentinel */ }

> +	{}
> +};
> +
> +static struct platform_driver dramc_drv = {
> +	.probe = dramc_probe,
> +	.remove = dramc_remove,
> +	.driver = {
> +		.name = "dramc_drv",
> +		.owner = THIS_MODULE,
> +		.of_match_table = dramc_of_ids,
> +	},
> +};

module_platform_driver(...)

> +
> +static int __init dramc_drv_init(void)

...so that function is not needed.

> +{
> +	int ret;
> +
> +	ret = platform_driver_register(&dramc_drv);
> +	if (ret) {
> +		pr_info("%s: init fail, ret 0x%x\n", __func__, ret);
> +		return ret;
> +	}
> +
> +	return ret;
> +}
> +
> +module_init(dramc_drv_init);
> +
> +MODULE_AUTHOR("Mediatek Corporation");

MODULE_AUTHOR("Author Name <your.email@mediatek.com>");

> +MODULE_DESCRIPTION("MediaTek DRAMC Driver");

MODULE_DESCRIPTION("MediaTek DRAM Controller driver");



...and I have a hunch that this series will need many versions before the code
quality bar reaches a nice level...

Cheers,
Angelo

> +MODULE_LICENSE("GPL");
Krzysztof Kozlowski Dec. 12, 2024, 11:02 a.m. UTC | #2 
On 12/12/2024 09:59, Crystal Guo wrote:
> Add MediaTek DRAMC driver to provide an interface that can
> obtain current DDR data rate.
> 
> Signed-off-by: Crystal Guo <crystal.guo@mediatek.com>
> ---
>  drivers/memory/Kconfig                 |   1 +
>  drivers/memory/Makefile                |   1 +
>  drivers/memory/mediatek/Kconfig        |  21 ++
>  drivers/memory/mediatek/Makefile       |   2 +
>  drivers/memory/mediatek/mtk-dramc.c    | 325 +++++++++++++++++++++++++
>  include/linux/soc/mediatek/mtk-dramc.h |  41 ++++
>  6 files changed, 391 insertions(+)
>  create mode 100644 drivers/memory/mediatek/Kconfig
>  create mode 100644 drivers/memory/mediatek/Makefile
>  create mode 100644 drivers/memory/mediatek/mtk-dramc.c
>  create mode 100644 include/linux/soc/mediatek/mtk-dramc.h
> 
> diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
> index c82d8d8a16ea..b1698549ff81 100644
> --- a/drivers/memory/Kconfig
> +++ b/drivers/memory/Kconfig
> @@ -227,5 +227,6 @@ config STM32_FMC2_EBI
>  
>  source "drivers/memory/samsung/Kconfig"
>  source "drivers/memory/tegra/Kconfig"
> +source "drivers/memory/mediatek/Kconfig"
>  
>  endif
> diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
> index d2e6ca9abbe0..cf1091449d2e 100644
> --- a/drivers/memory/Makefile
> +++ b/drivers/memory/Makefile
> @@ -27,6 +27,7 @@ obj-$(CONFIG_STM32_FMC2_EBI)	+= stm32-fmc2-ebi.o
>  
>  obj-$(CONFIG_SAMSUNG_MC)	+= samsung/
>  obj-$(CONFIG_TEGRA_MC)		+= tegra/
> +obj-$(CONFIG_HAVE_MTK_MC)	+= mediatek/

What is HAVE? Why this is not just MTK_MC or ARCH_MEDIATEK?

>  obj-$(CONFIG_TI_EMIF_SRAM)	+= ti-emif-sram.o
>  obj-$(CONFIG_FPGA_DFL_EMIF)	+= dfl-emif.o
>  
> diff --git a/drivers/memory/mediatek/Kconfig b/drivers/memory/mediatek/Kconfig
> new file mode 100644
> index 000000000000..00764cdb157e
> --- /dev/null
> +++ b/drivers/memory/mediatek/Kconfig
> @@ -0,0 +1,21 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +config HAVE_MTK_MC
> +	bool "MediaTek Memory Controller support"
> +	help
> +	  This option allows to enable MediaTek memory controller drivers,
> +	  which may include controllers for DRAM or others.
> +	  Select Y here if you need support for MediaTek memory controller.
> +	  If you don't need, select N.
> +
> +if HAVE_MTK_MC
> +
> +config MTK_DRAMC
> +	tristate "MediaTek DRAMC driver"
> +	depends on HAVE_MTK_MC

Feels useless, isn't it part of if?

> +	help
> +	  This option selects the MediaTek DRAMC driver, which provides
> +	  an interface for reporting the current data rate of DRAM.
> +	  Select Y here if you need support for the MediaTek DRAMC driver.
> +	  If you don't need, select N.
> +
> +endif
> diff --git a/drivers/memory/mediatek/Makefile b/drivers/memory/mediatek/Makefile
> new file mode 100644
> index 000000000000..a1395fc55b41
> --- /dev/null
> +++ b/drivers/memory/mediatek/Makefile
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0
> +obj-$(CONFIG_MTK_DRAMC)		+= mtk-dramc.o
> diff --git a/drivers/memory/mediatek/mtk-dramc.c b/drivers/memory/mediatek/mtk-dramc.c
> new file mode 100644
> index 000000000000..9c2c8e187a4a
> --- /dev/null
> +++ b/drivers/memory/mediatek/mtk-dramc.c
> @@ -0,0 +1,325 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2024 MediaTek Inc.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/device.h>
> +#include <linux/platform_device.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/printk.h>
> +#include <linux/io.h>
> +#include <linux/soc/mediatek/mtk-dramc.h>
> +
> +static struct platform_device *dramc_pdev;
> +static struct platform_driver dramc_drv;

Drop both. Don't write singleton code.

...

> +		if (!(dramc_dev_ptr->fmeter_dev_ptr)) {
> +			pr_info("%s: memory  alloc fail\n", __func__);
> +			return -ENOMEM;
> +		}
> +		ret = fmeter_init(pdev, dramc_dev_ptr->fmeter_dev_ptr, fmeter_version);
> +		if (ret) {
> +			pr_info("%s: fmeter_init fail\n", __func__);
> +			return -EINVAL;
> +		}
> +	} else {
> +		dramc_dev_ptr->fmeter_dev_ptr = NULL;
> +	}
> +	ret = driver_create_file(pdev->dev.driver, &driver_attr_dram_data_rate);
> +	if (ret) {
> +		pr_info("%s: fail to create dram_data_rate sysfs\n", __func__);
> +		return ret;
> +	}
> +
> +	platform_set_drvdata(pdev, dramc_dev_ptr);
> +	pr_info("%s: DRAM data rate = %d\n", __func__,
> +		mtk_dramc_get_data_rate());


This is terible coding style. Driver is in very poor shape.

Please perform extensive internal review in Mediatek to avoid sending
very poor quality contributions. This uses community resources in unfair
way. Few more comments, but all this code needs extensive rework and I
am not going to explain you basics of Linux Coding style, if you do not
want to take existing code as learning examples. Work with your
collegagues on that.


> +
> +	return ret;
> +}
> +
> +static unsigned int fmeter_v1(struct dramc_dev_t *dramc_dev_ptr)
> +{
> +	struct fmeter_dev_t *fmeter_dev_ptr =
> +		(struct fmeter_dev_t *)dramc_dev_ptr->fmeter_dev_ptr;
> +	unsigned int shu_lv_val;
> +	unsigned int pll_id_val;
> +	unsigned int sdmpcw_val;
> +	unsigned int posdiv_val;
> +	unsigned int ckdiv4_val;
> +	unsigned int offset;
> +	unsigned int vco_freq;
> +	unsigned int fbksel;
> +	unsigned int dqsopen;
> +	unsigned int async_ca;
> +	unsigned int dq_ser_mode;
> +
> +	shu_lv_val = (readl(dramc_dev_ptr->ddrphy_chn_base_ao[0] +
> +		fmeter_dev_ptr->shu_lv.offset) &
> +		fmeter_dev_ptr->shu_lv.mask) >>
> +		fmeter_dev_ptr->shu_lv.shift;
> +
> +	pll_id_val = (readl(dramc_dev_ptr->ddrphy_chn_base_ao[0] +
> +		fmeter_dev_ptr->pll_id.offset) &
> +		fmeter_dev_ptr->pll_id.mask) >>
> +		fmeter_dev_ptr->pll_id.shift;
> +
> +	offset = fmeter_dev_ptr->sdmpcw[pll_id_val].offset +
> +		fmeter_dev_ptr->shu_of * shu_lv_val;
> +	sdmpcw_val = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
> +		fmeter_dev_ptr->sdmpcw[pll_id_val].mask) >>
> +		fmeter_dev_ptr->sdmpcw[pll_id_val].shift;
> +
> +	offset = fmeter_dev_ptr->posdiv[pll_id_val].offset +
> +		fmeter_dev_ptr->shu_of * shu_lv_val;
> +	posdiv_val = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
> +		fmeter_dev_ptr->posdiv[pll_id_val].mask) >>
> +		fmeter_dev_ptr->posdiv[pll_id_val].shift;
> +
> +	offset = fmeter_dev_ptr->fbksel[pll_id_val].offset +
> +		fmeter_dev_ptr->shu_of * shu_lv_val;
> +	fbksel = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
> +		fmeter_dev_ptr->fbksel[pll_id_val].mask) >>
> +		fmeter_dev_ptr->fbksel[pll_id_val].shift;
> +
> +	offset = fmeter_dev_ptr->dqsopen[pll_id_val].offset +
> +		fmeter_dev_ptr->shu_of * shu_lv_val;
> +	dqsopen = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
> +		fmeter_dev_ptr->dqsopen[pll_id_val].mask) >>
> +		fmeter_dev_ptr->dqsopen[pll_id_val].shift;
> +
> +	offset = fmeter_dev_ptr->async_ca[pll_id_val].offset +
> +		fmeter_dev_ptr->shu_of * shu_lv_val;
> +	async_ca = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
> +		fmeter_dev_ptr->async_ca[pll_id_val].mask) >>
> +		fmeter_dev_ptr->async_ca[pll_id_val].shift;
> +
> +	offset = fmeter_dev_ptr->dq_ser_mode[pll_id_val].offset +
> +		fmeter_dev_ptr->shu_of * shu_lv_val;
> +	dq_ser_mode = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
> +		fmeter_dev_ptr->dq_ser_mode[pll_id_val].mask) >>
> +		fmeter_dev_ptr->dq_ser_mode[pll_id_val].shift;
> +	ckdiv4_val = (dq_ser_mode == 1); // 1: DIV4, 2: DIV8, 3: DIV16
> +
> +	posdiv_val &= ~(0x4);
> +
> +	vco_freq = ((fmeter_dev_ptr->crystal_freq) *
> +		(sdmpcw_val >> 7)) >> posdiv_val >> 1 >> ckdiv4_val
> +		<< fbksel;
> +
> +	if ((dqsopen == 1) && (async_ca == 1))
> +		vco_freq >>= 1;
> +
> +	return vco_freq;
> +}
> +
> +/*
> + * mtk_dramc_get_data_rate - calculate DRAM data rate
> + *
> + * Returns DRAM data rate (MB/s)
> + */
> +unsigned int mtk_dramc_get_data_rate(void)
> +{
> +	struct dramc_dev_t *dramc_dev_ptr;
> +	struct fmeter_dev_t *fmeter_dev_ptr;
> +
> +	if (!dramc_pdev)
> +		return 0;
> +
> +	dramc_dev_ptr =
> +		(struct dramc_dev_t *)platform_get_drvdata(dramc_pdev);
> +
> +	fmeter_dev_ptr = (struct fmeter_dev_t *)dramc_dev_ptr->fmeter_dev_ptr;
> +	if (!fmeter_dev_ptr)
> +		return 0;
> +
> +	if (fmeter_dev_ptr->version == 1)
> +		return fmeter_v1(dramc_dev_ptr);
> +	return 0;
> +}
> +EXPORT_SYMBOL(mtk_dramc_get_data_rate);

NAK, not used.

> +
> +static int dramc_remove(struct platform_device *pdev)
> +{
> +	dramc_pdev = NULL;
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id dramc_of_ids[] = {
> +	{.compatible = "mediatek,common-dramc",},
> +	{}
> +};
> +
> +static struct platform_driver dramc_drv = {
> +	.probe = dramc_probe,
> +	.remove = dramc_remove,
> +	.driver = {
> +		.name = "dramc_drv",
> +		.owner = THIS_MODULE,

NAK. You sent us 10 year old code, which means you replicated all the
bugs, issues and old-coding styles existing 10 years ago.

Start *FROM SCRATCH* from the newest driver, so you won't send us same
junk we already fixed during last 10 years.


> +		.of_match_table = dramc_of_ids,
> +	},
> +};
> +
> +static int __init dramc_drv_init(void)
> +{
> +	int ret;
> +
> +	ret = platform_driver_register(&dramc_drv);
> +	if (ret) {
> +		pr_info("%s: init fail, ret 0x%x\n", __func__, ret);
> +		return ret;
> +	}
> +
> +	return ret;
> +}
> +
> +module_init(dramc_drv_init);

No, just module_platform_driver

> +
> +MODULE_AUTHOR("Mediatek Corporation");
> +MODULE_DESCRIPTION("MediaTek DRAMC Driver");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/soc/mediatek/mtk-dramc.h b/include/linux/soc/mediatek/mtk-dramc.h
> new file mode 100644
> index 000000000000..95e7dbfe7d0e
> --- /dev/null
> +++ b/include/linux/soc/mediatek/mtk-dramc.h

Move everything into driver.

> @@ -0,0 +1,41 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2019 MediaTek Inc.
> + */
> +
> +#ifndef __MTK_DRAMC_H__
> +#define __MTK_DRAMC_H__
> +
> +struct reg_ctrl_t {
> +	unsigned int offset;
> +	unsigned int mask;
> +	unsigned int shift;
> +};
> +
> +struct fmeter_dev_t {
> +	unsigned int version;
> +	unsigned int crystal_freq;
> +	unsigned int shu_of;
> +	struct reg_ctrl_t shu_lv;
> +	struct reg_ctrl_t pll_id;
> +	struct reg_ctrl_t sdmpcw[2];
> +	struct reg_ctrl_t posdiv[2];
> +	struct reg_ctrl_t fbksel[2];
> +	struct reg_ctrl_t dqsopen[2];
> +	struct reg_ctrl_t async_ca[2];
> +	struct reg_ctrl_t dq_ser_mode[2];
> +};
> +
> +struct dramc_dev_t {
> +	unsigned int support_ch_cnt;
> +	void __iomem **dramc_chn_base_ao;
> +	void __iomem **dramc_chn_base_nao;
> +	void __iomem **ddrphy_chn_base_ao;
> +	void __iomem **ddrphy_chn_base_nao;
> +	void __iomem *sleep_base;
> +	void *fmeter_dev_ptr;
> +};
> +
> +unsigned int mtk_dramc_get_data_rate(void);


Drop, unused.

> +
> +#endif /* __MTK_DRAMC_H__ */


Best regards,
Krzysztof
kernel test robot Dec. 21, 2024, 1:42 a.m. UTC | #3 
Hi Crystal,

kernel test robot noticed the following build errors:

[auto build test ERROR on krzk-mem-ctrl/for-next]
[also build test ERROR on robh/for-next krzk-dt/for-next linus/master v6.13-rc3 next-20241220]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Crystal-Guo/memory-mediatek-Add-an-interface-to-get-current-DDR-data-rate/20241212-170306
base:   https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux-mem-ctrl.git for-next
patch link:    https://lore.kernel.org/r/20241212090029.13692-2-crystal.guo%40mediatek.com
patch subject: [PATCH 1/2] memory/mediatek: Add an interface to get current DDR data rate
config: m68k-allmodconfig (https://download.01.org/0day-ci/archive/20241221/202412210955.FvO0Pee3-lkp@intel.com/config)
compiler: m68k-linux-gcc (GCC) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241221/202412210955.FvO0Pee3-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202412210955.FvO0Pee3-lkp@intel.com/

All errors (new ones prefixed by >>):

>> drivers/memory/mediatek/mtk-dramc.c:300:19: error: initialization of 'void (*)(struct platform_device *)' from incompatible pointer type 'int (*)(struct platform_device *)' [-Wincompatible-pointer-types]
     300 |         .remove = dramc_remove,
         |                   ^~~~~~~~~~~~
   drivers/memory/mediatek/mtk-dramc.c:300:19: note: (near initialization for 'dramc_drv.<anonymous>.remove')


vim +300 drivers/memory/mediatek/mtk-dramc.c

   297	
   298	static struct platform_driver dramc_drv = {
   299		.probe = dramc_probe,
 > 300		.remove = dramc_remove,
   301		.driver = {
   302			.name = "dramc_drv",
   303			.owner = THIS_MODULE,
   304			.of_match_table = dramc_of_ids,
   305		},
   306	};
   307
kernel test robot Dec. 21, 2024, 11:03 a.m. UTC | #4 
Hi Crystal,

kernel test robot noticed the following build errors:

[auto build test ERROR on krzk-mem-ctrl/for-next]
[also build test ERROR on robh/for-next krzk-dt/for-next linus/master v6.13-rc3 next-20241220]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Crystal-Guo/memory-mediatek-Add-an-interface-to-get-current-DDR-data-rate/20241212-170306
base:   https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux-mem-ctrl.git for-next
patch link:    https://lore.kernel.org/r/20241212090029.13692-2-crystal.guo%40mediatek.com
patch subject: [PATCH 1/2] memory/mediatek: Add an interface to get current DDR data rate
config: hexagon-allmodconfig (https://download.01.org/0day-ci/archive/20241221/202412211805.ulwSEmZa-lkp@intel.com/config)
compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 9daf10ff8f29ba3a88a105aaa9d2379c21b77d35)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241221/202412211805.ulwSEmZa-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202412211805.ulwSEmZa-lkp@intel.com/

All errors (new ones prefixed by >>):

>> drivers/memory/mediatek/mtk-dramc.c:300:12: error: incompatible function pointer types initializing 'void (*)(struct platform_device *)' with an expression of type 'int (struct platform_device *)' [-Wincompatible-function-pointer-types]
     300 |         .remove = dramc_remove,
         |                   ^~~~~~~~~~~~
   1 error generated.


vim +300 drivers/memory/mediatek/mtk-dramc.c

   297	
   298	static struct platform_driver dramc_drv = {
   299		.probe = dramc_probe,
 > 300		.remove = dramc_remove,
   301		.driver = {
   302			.name = "dramc_drv",
   303			.owner = THIS_MODULE,
   304			.of_match_table = dramc_of_ids,
   305		},
   306	};
   307
diff mbox series

Patch

diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
index c82d8d8a16ea..b1698549ff81 100644
--- a/drivers/memory/Kconfig
+++ b/drivers/memory/Kconfig
@@ -227,5 +227,6 @@  config STM32_FMC2_EBI
 
 source "drivers/memory/samsung/Kconfig"
 source "drivers/memory/tegra/Kconfig"
+source "drivers/memory/mediatek/Kconfig"
 
 endif
diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
index d2e6ca9abbe0..cf1091449d2e 100644
--- a/drivers/memory/Makefile
+++ b/drivers/memory/Makefile
@@ -27,6 +27,7 @@  obj-$(CONFIG_STM32_FMC2_EBI)	+= stm32-fmc2-ebi.o
 
 obj-$(CONFIG_SAMSUNG_MC)	+= samsung/
 obj-$(CONFIG_TEGRA_MC)		+= tegra/
+obj-$(CONFIG_HAVE_MTK_MC)	+= mediatek/
 obj-$(CONFIG_TI_EMIF_SRAM)	+= ti-emif-sram.o
 obj-$(CONFIG_FPGA_DFL_EMIF)	+= dfl-emif.o
 
diff --git a/drivers/memory/mediatek/Kconfig b/drivers/memory/mediatek/Kconfig
new file mode 100644
index 000000000000..00764cdb157e
--- /dev/null
+++ b/drivers/memory/mediatek/Kconfig
@@ -0,0 +1,21 @@ 
+# SPDX-License-Identifier: GPL-2.0-only
+config HAVE_MTK_MC
+	bool "MediaTek Memory Controller support"
+	help
+	  This option allows to enable MediaTek memory controller drivers,
+	  which may include controllers for DRAM or others.
+	  Select Y here if you need support for MediaTek memory controller.
+	  If you don't need, select N.
+
+if HAVE_MTK_MC
+
+config MTK_DRAMC
+	tristate "MediaTek DRAMC driver"
+	depends on HAVE_MTK_MC
+	help
+	  This option selects the MediaTek DRAMC driver, which provides
+	  an interface for reporting the current data rate of DRAM.
+	  Select Y here if you need support for the MediaTek DRAMC driver.
+	  If you don't need, select N.
+
+endif
diff --git a/drivers/memory/mediatek/Makefile b/drivers/memory/mediatek/Makefile
new file mode 100644
index 000000000000..a1395fc55b41
--- /dev/null
+++ b/drivers/memory/mediatek/Makefile
@@ -0,0 +1,2 @@ 
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_MTK_DRAMC)		+= mtk-dramc.o
diff --git a/drivers/memory/mediatek/mtk-dramc.c b/drivers/memory/mediatek/mtk-dramc.c
new file mode 100644
index 000000000000..9c2c8e187a4a
--- /dev/null
+++ b/drivers/memory/mediatek/mtk-dramc.c
@@ -0,0 +1,325 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2024 MediaTek Inc.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/printk.h>
+#include <linux/io.h>
+#include <linux/soc/mediatek/mtk-dramc.h>
+
+static struct platform_device *dramc_pdev;
+static struct platform_driver dramc_drv;
+
+static int fmeter_init(struct platform_device *pdev,
+		       struct fmeter_dev_t *fmeter_dev_ptr, unsigned int fmeter_version)
+{
+	struct device_node *dramc_node = pdev->dev.of_node;
+	int ret;
+
+	ret = of_property_read_u32(dramc_node,
+				   "crystal-freq", &(fmeter_dev_ptr->crystal_freq));
+	ret |= of_property_read_u32(dramc_node,
+				    "shu-of", &(fmeter_dev_ptr->shu_of));
+	ret |= of_property_read_u32_array(dramc_node,
+					  "shu-lv", (unsigned int *)&(fmeter_dev_ptr->shu_lv), 3);
+	ret |= of_property_read_u32_array(dramc_node,
+					  "pll-id", (unsigned int *)&(fmeter_dev_ptr->pll_id), 3);
+	ret |= of_property_read_u32_array(dramc_node,
+					  "sdmpcw", (unsigned int *)(fmeter_dev_ptr->sdmpcw), 6);
+	ret |= of_property_read_u32_array(dramc_node,
+					  "posdiv", (unsigned int *)(fmeter_dev_ptr->posdiv), 6);
+	ret |= of_property_read_u32_array(dramc_node,
+					  "fbksel", (unsigned int *)(fmeter_dev_ptr->fbksel), 6);
+	ret |= of_property_read_u32_array(dramc_node,
+					  "dqsopen", (unsigned int *)(fmeter_dev_ptr->dqsopen), 6);
+	if (fmeter_version == 1) {
+		fmeter_dev_ptr->version = 1;
+		ret |= of_property_read_u32_array(dramc_node,
+			"async-ca", (unsigned int *)(fmeter_dev_ptr->async_ca), 6);
+		ret |= of_property_read_u32_array(dramc_node,
+			"dq-ser-mode", (unsigned int *)(fmeter_dev_ptr->dq_ser_mode), 6);
+	}
+	return ret;
+}
+
+static ssize_t dram_data_rate_show(struct device_driver *driver, char *buf)
+{
+	return snprintf(buf, PAGE_SIZE, "DRAM data rate = %d\n",
+		mtk_dramc_get_data_rate());
+}
+
+static DRIVER_ATTR_RO(dram_data_rate);
+
+static int dramc_probe(struct platform_device *pdev)
+{
+	struct device_node *dramc_node = pdev->dev.of_node;
+	struct dramc_dev_t *dramc_dev_ptr;
+	unsigned int fmeter_version;
+	struct resource *res;
+	unsigned int i, size;
+	int ret;
+
+	pr_info("%s: module probe.\n", __func__);
+	dramc_pdev = pdev;
+	dramc_dev_ptr = devm_kmalloc(&pdev->dev,
+				     sizeof(struct dramc_dev_t), GFP_KERNEL);
+
+	if (!dramc_dev_ptr)
+		return -ENOMEM;
+
+	ret = of_property_read_u32(dramc_node,
+				   "support-ch-cnt", &dramc_dev_ptr->support_ch_cnt);
+	if (ret) {
+		pr_info("%s: get support_ch_cnt fail\n", __func__);
+		return -EINVAL;
+	}
+
+	dramc_dev_ptr->sleep_base = of_iomap(dramc_node,
+					     dramc_dev_ptr->support_ch_cnt * 4);
+	if (IS_ERR(dramc_dev_ptr->sleep_base)) {
+		pr_info("%s: unable to map sleep base\n", __func__);
+		return -EINVAL;
+	}
+
+	size = sizeof(phys_addr_t) * dramc_dev_ptr->support_ch_cnt;
+	dramc_dev_ptr->dramc_chn_base_ao = devm_kmalloc(&pdev->dev,
+							size, GFP_KERNEL);
+	if (!(dramc_dev_ptr->dramc_chn_base_ao))
+		return -ENOMEM;
+	dramc_dev_ptr->dramc_chn_base_nao = devm_kmalloc(&pdev->dev,
+							 size, GFP_KERNEL);
+	if (!(dramc_dev_ptr->dramc_chn_base_nao))
+		return -ENOMEM;
+	dramc_dev_ptr->ddrphy_chn_base_ao = devm_kmalloc(&pdev->dev,
+							 size, GFP_KERNEL);
+	if (!(dramc_dev_ptr->ddrphy_chn_base_ao))
+		return -ENOMEM;
+	dramc_dev_ptr->ddrphy_chn_base_nao = devm_kmalloc(&pdev->dev,
+							  size, GFP_KERNEL);
+	if (!(dramc_dev_ptr->ddrphy_chn_base_nao))
+		return -ENOMEM;
+
+	for (i = 0; i < dramc_dev_ptr->support_ch_cnt; i++) {
+		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
+		dramc_dev_ptr->dramc_chn_base_ao[i] =
+			devm_ioremap_resource(&pdev->dev, res);
+		if (IS_ERR(dramc_dev_ptr->dramc_chn_base_ao[i])) {
+			pr_info("%s: unable to map ch%d DRAMC AO base\n",
+				__func__, i);
+			return -EINVAL;
+		}
+
+		res = platform_get_resource(pdev, IORESOURCE_MEM,
+					    i + dramc_dev_ptr->support_ch_cnt);
+		dramc_dev_ptr->dramc_chn_base_nao[i] =
+			devm_ioremap_resource(&pdev->dev, res);
+		if (IS_ERR(dramc_dev_ptr->dramc_chn_base_nao[i])) {
+			pr_info("%s: unable to map ch%d DRAMC NAO base\n",
+				__func__, i);
+			return -EINVAL;
+		}
+
+		res = platform_get_resource(pdev, IORESOURCE_MEM,
+					    i + dramc_dev_ptr->support_ch_cnt * 2);
+		dramc_dev_ptr->ddrphy_chn_base_ao[i] =
+			devm_ioremap_resource(&pdev->dev, res);
+		if (IS_ERR(dramc_dev_ptr->ddrphy_chn_base_ao[i])) {
+			pr_info("%s: unable to map ch%d DDRPHY AO base\n",
+				__func__, i);
+			return -EINVAL;
+		}
+
+		res = platform_get_resource(pdev, IORESOURCE_MEM,
+					    i + dramc_dev_ptr->support_ch_cnt * 3);
+		dramc_dev_ptr->ddrphy_chn_base_nao[i] =
+			devm_ioremap_resource(&pdev->dev, res);
+		if (IS_ERR(dramc_dev_ptr->ddrphy_chn_base_nao[i])) {
+			pr_info("%s: unable to map ch%d DDRPHY NAO base\n",
+				__func__, i);
+			return -EINVAL;
+		}
+	}
+
+	ret = of_property_read_u32(dramc_node, "fmeter-version", &fmeter_version);
+	if (ret) {
+		pr_info("%s: get fmeter_version fail\n", __func__);
+		return -EINVAL;
+	}
+	pr_info("%s: fmeter_version(%d)\n", __func__, fmeter_version);
+
+	if (fmeter_version == 1) {
+		dramc_dev_ptr->fmeter_dev_ptr = devm_kmalloc(&pdev->dev,
+							     sizeof(struct fmeter_dev_t),
+							     GFP_KERNEL);
+		if (!(dramc_dev_ptr->fmeter_dev_ptr)) {
+			pr_info("%s: memory  alloc fail\n", __func__);
+			return -ENOMEM;
+		}
+		ret = fmeter_init(pdev, dramc_dev_ptr->fmeter_dev_ptr, fmeter_version);
+		if (ret) {
+			pr_info("%s: fmeter_init fail\n", __func__);
+			return -EINVAL;
+		}
+	} else {
+		dramc_dev_ptr->fmeter_dev_ptr = NULL;
+	}
+	ret = driver_create_file(pdev->dev.driver, &driver_attr_dram_data_rate);
+	if (ret) {
+		pr_info("%s: fail to create dram_data_rate sysfs\n", __func__);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, dramc_dev_ptr);
+	pr_info("%s: DRAM data rate = %d\n", __func__,
+		mtk_dramc_get_data_rate());
+
+	return ret;
+}
+
+static unsigned int fmeter_v1(struct dramc_dev_t *dramc_dev_ptr)
+{
+	struct fmeter_dev_t *fmeter_dev_ptr =
+		(struct fmeter_dev_t *)dramc_dev_ptr->fmeter_dev_ptr;
+	unsigned int shu_lv_val;
+	unsigned int pll_id_val;
+	unsigned int sdmpcw_val;
+	unsigned int posdiv_val;
+	unsigned int ckdiv4_val;
+	unsigned int offset;
+	unsigned int vco_freq;
+	unsigned int fbksel;
+	unsigned int dqsopen;
+	unsigned int async_ca;
+	unsigned int dq_ser_mode;
+
+	shu_lv_val = (readl(dramc_dev_ptr->ddrphy_chn_base_ao[0] +
+		fmeter_dev_ptr->shu_lv.offset) &
+		fmeter_dev_ptr->shu_lv.mask) >>
+		fmeter_dev_ptr->shu_lv.shift;
+
+	pll_id_val = (readl(dramc_dev_ptr->ddrphy_chn_base_ao[0] +
+		fmeter_dev_ptr->pll_id.offset) &
+		fmeter_dev_ptr->pll_id.mask) >>
+		fmeter_dev_ptr->pll_id.shift;
+
+	offset = fmeter_dev_ptr->sdmpcw[pll_id_val].offset +
+		fmeter_dev_ptr->shu_of * shu_lv_val;
+	sdmpcw_val = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
+		fmeter_dev_ptr->sdmpcw[pll_id_val].mask) >>
+		fmeter_dev_ptr->sdmpcw[pll_id_val].shift;
+
+	offset = fmeter_dev_ptr->posdiv[pll_id_val].offset +
+		fmeter_dev_ptr->shu_of * shu_lv_val;
+	posdiv_val = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
+		fmeter_dev_ptr->posdiv[pll_id_val].mask) >>
+		fmeter_dev_ptr->posdiv[pll_id_val].shift;
+
+	offset = fmeter_dev_ptr->fbksel[pll_id_val].offset +
+		fmeter_dev_ptr->shu_of * shu_lv_val;
+	fbksel = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
+		fmeter_dev_ptr->fbksel[pll_id_val].mask) >>
+		fmeter_dev_ptr->fbksel[pll_id_val].shift;
+
+	offset = fmeter_dev_ptr->dqsopen[pll_id_val].offset +
+		fmeter_dev_ptr->shu_of * shu_lv_val;
+	dqsopen = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
+		fmeter_dev_ptr->dqsopen[pll_id_val].mask) >>
+		fmeter_dev_ptr->dqsopen[pll_id_val].shift;
+
+	offset = fmeter_dev_ptr->async_ca[pll_id_val].offset +
+		fmeter_dev_ptr->shu_of * shu_lv_val;
+	async_ca = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
+		fmeter_dev_ptr->async_ca[pll_id_val].mask) >>
+		fmeter_dev_ptr->async_ca[pll_id_val].shift;
+
+	offset = fmeter_dev_ptr->dq_ser_mode[pll_id_val].offset +
+		fmeter_dev_ptr->shu_of * shu_lv_val;
+	dq_ser_mode = (readl(dramc_dev_ptr->ddrphy_chn_base_nao[0] + offset) &
+		fmeter_dev_ptr->dq_ser_mode[pll_id_val].mask) >>
+		fmeter_dev_ptr->dq_ser_mode[pll_id_val].shift;
+	ckdiv4_val = (dq_ser_mode == 1); // 1: DIV4, 2: DIV8, 3: DIV16
+
+	posdiv_val &= ~(0x4);
+
+	vco_freq = ((fmeter_dev_ptr->crystal_freq) *
+		(sdmpcw_val >> 7)) >> posdiv_val >> 1 >> ckdiv4_val
+		<< fbksel;
+
+	if ((dqsopen == 1) && (async_ca == 1))
+		vco_freq >>= 1;
+
+	return vco_freq;
+}
+
+/*
+ * mtk_dramc_get_data_rate - calculate DRAM data rate
+ *
+ * Returns DRAM data rate (MB/s)
+ */
+unsigned int mtk_dramc_get_data_rate(void)
+{
+	struct dramc_dev_t *dramc_dev_ptr;
+	struct fmeter_dev_t *fmeter_dev_ptr;
+
+	if (!dramc_pdev)
+		return 0;
+
+	dramc_dev_ptr =
+		(struct dramc_dev_t *)platform_get_drvdata(dramc_pdev);
+
+	fmeter_dev_ptr = (struct fmeter_dev_t *)dramc_dev_ptr->fmeter_dev_ptr;
+	if (!fmeter_dev_ptr)
+		return 0;
+
+	if (fmeter_dev_ptr->version == 1)
+		return fmeter_v1(dramc_dev_ptr);
+	return 0;
+}
+EXPORT_SYMBOL(mtk_dramc_get_data_rate);
+
+static int dramc_remove(struct platform_device *pdev)
+{
+	dramc_pdev = NULL;
+
+	return 0;
+}
+
+static const struct of_device_id dramc_of_ids[] = {
+	{.compatible = "mediatek,common-dramc",},
+	{}
+};
+
+static struct platform_driver dramc_drv = {
+	.probe = dramc_probe,
+	.remove = dramc_remove,
+	.driver = {
+		.name = "dramc_drv",
+		.owner = THIS_MODULE,
+		.of_match_table = dramc_of_ids,
+	},
+};
+
+static int __init dramc_drv_init(void)
+{
+	int ret;
+
+	ret = platform_driver_register(&dramc_drv);
+	if (ret) {
+		pr_info("%s: init fail, ret 0x%x\n", __func__, ret);
+		return ret;
+	}
+
+	return ret;
+}
+
+module_init(dramc_drv_init);
+
+MODULE_AUTHOR("Mediatek Corporation");
+MODULE_DESCRIPTION("MediaTek DRAMC Driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/soc/mediatek/mtk-dramc.h b/include/linux/soc/mediatek/mtk-dramc.h
new file mode 100644
index 000000000000..95e7dbfe7d0e
--- /dev/null
+++ b/include/linux/soc/mediatek/mtk-dramc.h
@@ -0,0 +1,41 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2019 MediaTek Inc.
+ */
+
+#ifndef __MTK_DRAMC_H__
+#define __MTK_DRAMC_H__
+
+struct reg_ctrl_t {
+	unsigned int offset;
+	unsigned int mask;
+	unsigned int shift;
+};
+
+struct fmeter_dev_t {
+	unsigned int version;
+	unsigned int crystal_freq;
+	unsigned int shu_of;
+	struct reg_ctrl_t shu_lv;
+	struct reg_ctrl_t pll_id;
+	struct reg_ctrl_t sdmpcw[2];
+	struct reg_ctrl_t posdiv[2];
+	struct reg_ctrl_t fbksel[2];
+	struct reg_ctrl_t dqsopen[2];
+	struct reg_ctrl_t async_ca[2];
+	struct reg_ctrl_t dq_ser_mode[2];
+};
+
+struct dramc_dev_t {
+	unsigned int support_ch_cnt;
+	void __iomem **dramc_chn_base_ao;
+	void __iomem **dramc_chn_base_nao;
+	void __iomem **ddrphy_chn_base_ao;
+	void __iomem **ddrphy_chn_base_nao;
+	void __iomem *sleep_base;
+	void *fmeter_dev_ptr;
+};
+
+unsigned int mtk_dramc_get_data_rate(void);
+
+#endif /* __MTK_DRAMC_H__ */