Commit 9cc832d3 authored by Marek Vasut's avatar Marek Vasut Committed by Shawn Guo
Browse files

soc: imx8m: Probe the SoC driver as platform driver 



With driver_async_probe=* on kernel command line, the following trace is
produced because on i.MX8M Plus hardware because the soc-imx8m.c driver
calls of_clk_get_by_name() which returns -EPROBE_DEFER because the clock
driver is not yet probed. This was not detected during regular testing
without driver_async_probe.

Convert the SoC code to platform driver and instantiate a platform device
in its current device_initcall() to probe the platform driver. Rework
.soc_revision callback to always return valid error code and return SoC
revision via parameter. This way, if anything in the .soc_revision callback
return -EPROBE_DEFER, it gets propagated to .probe and the .probe will get
retried later.

"
------------[ cut here ]------------
WARNING: CPU: 1 PID: 1 at drivers/soc/imx/soc-imx8m.c:115 imx8mm_soc_revision+0xdc/0x180
CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.11.0-next-20240924-00002-g2062bb554dea #603
Hardware name: DH electronics i.MX8M Plus DHCOM Premium Developer Kit (3) (DT)
pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : imx8mm_soc_revision+0xdc/0x180
lr : imx8mm_soc_revision+0xd0/0x180
sp : ffff8000821fbcc0
x29: ffff8000821fbce0 x28: 0000000000000000 x27: ffff800081810120
x26: ffff8000818a9970 x25: 0000000000000006 x24: 0000000000824311
x23: ffff8000817f42c8 x22: ffff0000df8be210 x21: fffffffffffffdfb
x20: ffff800082780000 x19: 0000000000000001 x18: ffffffffffffffff
x17: ffff800081fff418 x16: ffff8000823e1000 x15: ffff0000c03b65e8
x14: ffff0000c00051b0 x13: ffff800082790000 x12: 0000000000000801
x11: ffff80008278ffff x10: ffff80008209d3a6 x9 : ffff80008062e95c
x8 : ffff8000821fb9a0 x7 : 0000000000000000 x6 : 00000000000080e3
x5 : ffff0000df8c03d8 x4 : 0000000000000000 x3 : 0000000000000000
x2 : 0000000000000000 x1 : fffffffffffffdfb x0 : fffffffffffffdfb
Call trace:
 imx8mm_soc_revision+0xdc/0x180
 imx8_soc_init+0xb0/0x1e0
 do_one_initcall+0x94/0x1a8
 kernel_init_freeable+0x240/0x2a8
 kernel_init+0x28/0x140
 ret_from_fork+0x10/0x20
---[ end trace 0000000000000000 ]---
SoC: i.MX8MP revision 1.1
"

Signed-off-by: default avatarMarek Vasut <marex@denx.de>
Signed-off-by: default avatarShawn Guo <shawnguo@kernel.org>
parent 9852d85e

drivers/soc/imx/soc-imx8m.c

+85 −22
Original line number Diff line number Diff line
@@ -30,7 +30,7 @@ 


struct imx8_soc_data {

	char *name;

	u32 (*soc_revision)(void);

	int (*soc_revision)(u32 *socrev);

};



static u64 soc_uid;
@@ -51,24 +51,29 @@ static u32 imx8mq_soc_revision_from_atf(void) 
static inline u32 imx8mq_soc_revision_from_atf(void) { return 0; };

#endif



static u32 __init imx8mq_soc_revision(void)

static int imx8mq_soc_revision(u32 *socrev)

{

	struct device_node *np;

	void __iomem *ocotp_base;

	u32 magic;

	u32 rev;

	struct clk *clk;

	int ret;



	np = of_find_compatible_node(NULL, NULL, "fsl,imx8mq-ocotp");

	if (!np)

		return 0;

		return -EINVAL;



	ocotp_base = of_iomap(np, 0);

	WARN_ON(!ocotp_base);

	if (!ocotp_base) {

		ret = -EINVAL;

		goto err_iomap;

	}



	clk = of_clk_get_by_name(np, NULL);

	if (IS_ERR(clk)) {

		WARN_ON(IS_ERR(clk));

		return 0;

		ret = PTR_ERR(clk);

		goto err_clk;

	}



	clk_prepare_enable(clk);
@@ -88,32 +93,45 @@ static u32 __init imx8mq_soc_revision(void) 
	soc_uid <<= 32;

	soc_uid |= readl_relaxed(ocotp_base + OCOTP_UID_LOW);



	*socrev = rev;



	clk_disable_unprepare(clk);

	clk_put(clk);

	iounmap(ocotp_base);

	of_node_put(np);



	return rev;

	return 0;



err_clk:

	iounmap(ocotp_base);

err_iomap:

	of_node_put(np);

	return ret;

}



static void __init imx8mm_soc_uid(void)

static int imx8mm_soc_uid(void)

{

	void __iomem *ocotp_base;

	struct device_node *np;

	struct clk *clk;

	int ret = 0;

	u32 offset = of_machine_is_compatible("fsl,imx8mp") ?

		     IMX8MP_OCOTP_UID_OFFSET : 0;



	np = of_find_compatible_node(NULL, NULL, "fsl,imx8mm-ocotp");

	if (!np)

		return;

		return -EINVAL;



	ocotp_base = of_iomap(np, 0);

	WARN_ON(!ocotp_base);

	if (!ocotp_base) {

		ret = -EINVAL;

		goto err_iomap;

	}



	clk = of_clk_get_by_name(np, NULL);

	if (IS_ERR(clk)) {

		WARN_ON(IS_ERR(clk));

		return;

		ret = PTR_ERR(clk);

		goto err_clk;

	}



	clk_prepare_enable(clk);
@@ -124,31 +142,41 @@ static void __init imx8mm_soc_uid(void) 


	clk_disable_unprepare(clk);

	clk_put(clk);



err_clk:

	iounmap(ocotp_base);

err_iomap:

	of_node_put(np);



	return ret;

}



static u32 __init imx8mm_soc_revision(void)

static int imx8mm_soc_revision(u32 *socrev)

{

	struct device_node *np;

	void __iomem *anatop_base;

	u32 rev;

	int ret;



	np = of_find_compatible_node(NULL, NULL, "fsl,imx8mm-anatop");

	if (!np)

		return 0;

		return -EINVAL;



	anatop_base = of_iomap(np, 0);

	WARN_ON(!anatop_base);

	if (!anatop_base) {

		ret = -EINVAL;

		goto err_iomap;

	}



	rev = readl_relaxed(anatop_base + ANADIG_DIGPROG_IMX8MM);

	*socrev = readl_relaxed(anatop_base + ANADIG_DIGPROG_IMX8MM);



	iounmap(anatop_base);

	of_node_put(np);



	imx8mm_soc_uid();

	return imx8mm_soc_uid();



	return rev;

err_iomap:

	of_node_put(np);

	return ret;

}



static const struct imx8_soc_data imx8mq_soc_data = {
@@ -184,7 +212,7 @@ static __maybe_unused const struct of_device_id imx8_soc_match[] = { 
	kasprintf(GFP_KERNEL, "%d.%d", (soc_rev >> 4) & 0xf,  soc_rev & 0xf) : \

	"unknown"



static int __init imx8_soc_init(void)

static int imx8m_soc_probe(struct platform_device *pdev)

{

	struct soc_device_attribute *soc_dev_attr;

	struct soc_device *soc_dev;
@@ -212,8 +240,11 @@ static int __init imx8_soc_init(void) 
	data = id->data;

	if (data) {

		soc_dev_attr->soc_id = data->name;

		if (data->soc_revision)

			soc_rev = data->soc_revision();

		if (data->soc_revision) {

			ret = data->soc_revision(&soc_rev);

			if (ret)

				goto free_soc;

		}

	}



	soc_dev_attr->revision = imx8_revision(soc_rev);
@@ -251,6 +282,38 @@ static int __init imx8_soc_init(void) 
	kfree(soc_dev_attr);

	return ret;

}



static struct platform_driver imx8m_soc_driver = {

	.probe = imx8m_soc_probe,

	.driver = {

		.name = "imx8m-soc",

	},

};



static int __init imx8_soc_init(void)

{

	struct platform_device *pdev;

	int ret;



	/* No match means this is non-i.MX8M hardware, do nothing. */

	if (!of_match_node(imx8_soc_match, of_root))

		return 0;



	ret = platform_driver_register(&imx8m_soc_driver);

	if (ret) {

		pr_err("Failed to register imx8m-soc platform driver: %d\n", ret);

		return ret;

	}



	pdev = platform_device_register_simple("imx8m-soc", -1, NULL, 0);

	if (IS_ERR(pdev)) {

		pr_err("Failed to register imx8m-soc platform device: %ld\n", PTR_ERR(pdev));

		platform_driver_unregister(&imx8m_soc_driver);

		return PTR_ERR(pdev);

	}



	return 0;

}

device_initcall(imx8_soc_init);

MODULE_DESCRIPTION("NXP i.MX8M SoC driver");

MODULE_LICENSE("GPL");