Re: [PATCH] soc: imx: Add generic i.MX8 SoC driver

[Stefan Agner <stefan@agner.ch>]

On 03.02.2019 12:49, Abel Vesa wrote:
> Add generic i.MX8 SoC driver along with the i.MX8MQ SoC specific code.
> 
> Signed-off-by: Abel Vesa <abel.vesa@nxp.com>
> ---
>  drivers/soc/imx/Makefile   |   1 +
>  drivers/soc/imx/soc-imx8.c | 108 +++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 109 insertions(+)
>  create mode 100644 drivers/soc/imx/soc-imx8.c
> 
> diff --git a/drivers/soc/imx/Makefile b/drivers/soc/imx/Makefile
> index 506a6f3..d6b529e0 100644
> --- a/drivers/soc/imx/Makefile
> +++ b/drivers/soc/imx/Makefile
> @@ -1,2 +1,3 @@
>  obj-$(CONFIG_HAVE_IMX_GPC) += gpc.o
>  obj-$(CONFIG_IMX_GPCV2_PM_DOMAINS) += gpcv2.o
> +obj-$(CONFIG_ARCH_MXC) += soc-imx8.o
> diff --git a/drivers/soc/imx/soc-imx8.c b/drivers/soc/imx/soc-imx8.c
> new file mode 100644
> index 0000000..69fe04e
> --- /dev/null
> +++ b/drivers/soc/imx/soc-imx8.c
> @@ -0,0 +1,108 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright 2019 NXP.
> + */
> +
> +#include <linux/init.h>
> +#include <linux/io.h>
> +#include <linux/of_address.h>
> +#include <linux/slab.h>
> +#include <linux/sys_soc.h>
> +#include <linux/platform_device.h>
> +#include <linux/of.h>
> +
> +#define ANADIG_DIGPROG		0x6c
> +
> +struct imx8_soc_data {
> +	char *name;
> +	u32 (*soc_revision)(void);
> +};
> +
> +static u32 __init imx_init_revision_from_anatop(void)
> +{
> +	struct device_node *np;
> +	void __iomem *anatop_base;
> +	u32 digprog;
> +
> +	np = of_find_compatible_node(NULL, NULL, "fsl,imx8mq-anatop");
> +	anatop_base = of_iomap(np, 0);
> +	WARN_ON(!anatop_base);
> +	digprog = readl_relaxed(anatop_base + ANADIG_DIGPROG);
> +	iounmap(anatop_base);
> +
> +	/*
> +	 * Bit[7:4] is the base layer revision,
> +	 * Bit[3:0] is the metal layer revision
> +	 * e.g. 0x10 stands for Tapeout 1.0
> +	 */
> +	return digprog & 0xff;
> +}
> +
> +u32 imx8mq_soc_revision(void)

Since imx_init_revision_from_anatop is __init, you should make this
__init too.

> +{
> +	return imx_init_revision_from_anatop();
> +}
> +
> +struct imx8_soc_data imx8mq_soc_data = {
> +	.name = "i.MX8MQ",
> +	.soc_revision = imx8mq_soc_revision,
> +};

Can we make this const?

> +
> +static const struct of_device_id imx8_soc_match[] = {
> +	{ .compatible = "fsl,imx8mq", .data = &imx8mq_soc_data, },
> +	{ }
> +};
> +
> +static int __init imx8_soc_init(void)
> +{
> +	struct soc_device_attribute *soc_dev_attr;
> +	struct soc_device *soc_dev;
> +	struct device_node *root;
> +	const struct of_device_id *id;
> +	u32 soc_rev = 0;
> +	const struct imx8_soc_data *data;
> +	int ret;
> +
> +	soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
> +	if (!soc_dev_attr)
> +		return -ENODEV;
> +
> +	soc_dev_attr->family = "Freescale i.MX";
> +
> +	root = of_find_node_by_path("/");
> +	ret = of_property_read_string(root, "model", &soc_dev_attr->machine);
> +	if (ret)
> +		goto free_soc;
> +
> +	id = of_match_node(imx8_soc_match, root);
> +	if (!id)
> +		goto free_soc;

In this and the error case above you also need to make sure to call
of_node_put.

--
Stefan

> +
> +	of_node_put(root);
> +
> +	data = id->data;
> +	if (data) {
> +		soc_dev_attr->soc_id = data->name;
> +		if (data->soc_revision)
> +			soc_rev = data->soc_revision();
> +	}
> +
> +	soc_dev_attr->revision = kasprintf(GFP_KERNEL, "%d.%d",
> +					   (soc_rev >> 4) & 0xf,
> +					    soc_rev & 0xf);
> +	if (!soc_dev_attr->revision)
> +		goto free_soc;
> +
> +	soc_dev = soc_device_register(soc_dev_attr);
> +	if (IS_ERR(soc_dev))
> +		goto free_rev;
> +
> +	return 0;
> +
> +free_rev:
> +	kfree(soc_dev_attr->revision);
> +free_soc:
> +	kfree(soc_dev_attr);
> +	return -ENODEV;
> +}
> +device_initcall(imx8_soc_init);