[PATCH 1/2] soc: imx: add i.MX8QXP SoC driver support

[Anson Huang]

Add i.MX8QXP SoC driver support, introduce driver dependency
into Kconfig as CONFIG_IMX_SCU must be selected to support
i.MX8QXP, also need to use platform driver model to make sure
IMX_SCU driver is probed before i.MX8 SoC driver.

With this patch, SoC info can be read from sysfs:

i.mx8qxp-mek# cat /sys/devices/soc0/family
Freescale i.MX

i.mx8qxp-mek# cat /sys/devices/soc0/soc_id
i.MX8QXP

i.mx8qxp-mek# cat /sys/devices/soc0/machine
Freescale i.MX8QXP MEK

i.mx8qxp-mek# cat /sys/devices/soc0/revision
1.1

Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
---
 drivers/soc/imx/Kconfig    |   4 ++
 drivers/soc/imx/Makefile   |   2 +-
 drivers/soc/imx/soc-imx8.c | 126 ++++++++++++++++++++++++++++++++++++++++++---
 3 files changed, 124 insertions(+), 8 deletions(-)

diff --git a/drivers/soc/imx/Kconfig b/drivers/soc/imx/Kconfig
index d80f899..a4353f9 100644
--- a/drivers/soc/imx/Kconfig
+++ b/drivers/soc/imx/Kconfig
@@ -7,4 +7,8 @@ config IMX_GPCV2_PM_DOMAINS
 	select PM_GENERIC_DOMAINS
 	default y if SOC_IMX7D
 
+config IMX8_SOC
+	bool "i.MX8 SoC driver"
+	depends on ARCH_MXC && IMX_SCU
+
 endmenu
diff --git a/drivers/soc/imx/Makefile b/drivers/soc/imx/Makefile
index d6b529e0..5bf23f8 100644
--- a/drivers/soc/imx/Makefile
+++ b/drivers/soc/imx/Makefile
@@ -1,3 +1,3 @@
 obj-$(CONFIG_HAVE_IMX_GPC) += gpc.o
 obj-$(CONFIG_IMX_GPCV2_PM_DOMAINS) += gpcv2.o
-obj-$(CONFIG_ARCH_MXC) += soc-imx8.o
+obj-$(CONFIG_IMX8_SOC) += soc-imx8.o
diff --git a/drivers/soc/imx/soc-imx8.c b/drivers/soc/imx/soc-imx8.c
index fc6429f..3ad0b1c 100644
--- a/drivers/soc/imx/soc-imx8.c
+++ b/drivers/soc/imx/soc-imx8.c
@@ -3,8 +3,11 @@
  * Copyright 2019 NXP.
  */
 
+#include <dt-bindings/firmware/imx/rsrc.h>
+#include <linux/firmware/imx/sci.h>
 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/module.h>
 #include <linux/of_address.h>
 #include <linux/slab.h>
 #include <linux/sys_soc.h>
@@ -16,12 +19,61 @@
 #define IMX8MQ_SW_INFO_B1		0x40
 #define IMX8MQ_SW_MAGIC_B1		0xff0055aa
 
+#define IMX8_SOC_DRIVER_NAME		"imx8-soc"
+
+static struct imx_sc_ipc *soc_ipc_handle;
+static struct platform_device *imx8_soc_pdev;
+
+struct imx_sc_msg_misc_get_soc_id {
+	struct imx_sc_rpc_msg hdr;
+	union {
+		struct {
+			u32 control;
+			u16 resource;
+		} send;
+		struct {
+			u32 id;
+			u16 reserved;
+		} resp;
+	} data;
+};
+
 struct imx8_soc_data {
 	char *name;
 	u32 (*soc_revision)(void);
+	bool have_imx_scu;
 };
 
-static u32 __init imx8mq_soc_revision(void)
+static u32 imx8qxp_soc_revision(void)
+{
+	struct imx_sc_msg_misc_get_soc_id msg;
+	struct imx_sc_rpc_msg *hdr = &msg.hdr;
+	u32 rev = 0;
+	int ret;
+
+	hdr->ver = IMX_SC_RPC_VERSION;
+	hdr->svc = IMX_SC_RPC_SVC_MISC;
+	hdr->func = IMX_SC_MISC_FUNC_GET_CONTROL;
+	hdr->size = 3;
+
+	msg.data.send.control = IMX_SC_C_ID;
+	msg.data.send.resource = IMX_SC_R_SYSTEM;
+
+	ret = imx_scu_call_rpc(soc_ipc_handle, &msg, true);
+	if (ret) {
+		dev_err(&imx8_soc_pdev->dev,
+			"misc get control failed, ret %d\n", ret);
+		return rev;
+	}
+
+	/* format revision value passed from SCU firmware */
+	rev = (msg.data.resp.id >> 5) & 0xf;
+	rev = (((rev >> 2) + 1) << 4) | (rev & 0x3);
+
+	return rev;
+}
+
+static u32 imx8mq_soc_revision(void)
 {
 	struct device_node *np;
 	void __iomem *ocotp_base;
@@ -49,10 +101,18 @@ static u32 __init imx8mq_soc_revision(void)
 static const struct imx8_soc_data imx8mq_soc_data = {
 	.name = "i.MX8MQ",
 	.soc_revision = imx8mq_soc_revision,
+	.have_imx_scu = false,
+};
+
+static const struct imx8_soc_data imx8qxp_soc_data = {
+	.name = "i.MX8QXP",
+	.soc_revision = imx8qxp_soc_revision,
+	.have_imx_scu = true,
 };
 
 static const struct of_device_id imx8_soc_match[] = {
 	{ .compatible = "fsl,imx8mq", .data = &imx8mq_soc_data, },
+	{ .compatible = "fsl,imx8qxp", .data = &imx8qxp_soc_data, },
 	{ }
 };
 
@@ -61,7 +121,7 @@ static 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 imx8_soc_probe(struct platform_device *pdev)
 {
 	struct soc_device_attribute *soc_dev_attr;
 	struct soc_device *soc_dev;
@@ -83,25 +143,37 @@ static int __init imx8_soc_init(void)
 		goto free_soc;
 
 	id = of_match_node(imx8_soc_match, root);
-	if (!id)
+	if (!id) {
+		ret = -ENODEV;
 		goto free_soc;
+	}
 
 	of_node_put(root);
 
 	data = id->data;
 	if (data) {
+		if (data->have_imx_scu) {
+			ret = imx_scu_get_handle(&soc_ipc_handle);
+			if (ret)
+				goto free_soc;
+		}
+
 		soc_dev_attr->soc_id = data->name;
 		if (data->soc_revision)
 			soc_rev = data->soc_revision();
 	}
 
 	soc_dev_attr->revision = imx8_revision(soc_rev);
-	if (!soc_dev_attr->revision)
+	if (!soc_dev_attr->revision) {
+		ret = -ENODEV;
 		goto free_soc;
+	}
 
 	soc_dev = soc_device_register(soc_dev_attr);
-	if (IS_ERR(soc_dev))
+	if (IS_ERR(soc_dev)) {
+		ret = -ENODEV;
 		goto free_rev;
+	}
 
 	return 0;
 
@@ -110,6 +182,46 @@ static int __init imx8_soc_init(void)
 free_soc:
 	kfree(soc_dev_attr);
 	of_node_put(root);
-	return -ENODEV;
+	return ret;
 }
-device_initcall(imx8_soc_init);
+
+static struct platform_driver imx8_soc_driver = {
+	.driver = {
+		.name = IMX8_SOC_DRIVER_NAME,
+	},
+	.probe = imx8_soc_probe,
+};
+
+static int __init imx8_soc_init(void)
+{
+	int ret;
+
+	ret = platform_driver_register(&imx8_soc_driver);
+	if (ret)
+		return ret;
+
+	imx8_soc_pdev =
+		platform_device_register_simple(IMX8_SOC_DRIVER_NAME,
+						-1,
+						NULL,
+						0);
+	if (IS_ERR(imx8_soc_pdev)) {
+		ret = PTR_ERR(imx8_soc_pdev);
+		goto unreg_platform_driver;
+	}
+
+	return 0;
+
+unreg_platform_driver:
+	platform_driver_unregister(&imx8_soc_driver);
+	return ret;
+}
+
+static void __exit imx8_soc_exit(void)
+{
+	platform_device_unregister(imx8_soc_pdev);
+	platform_driver_unregister(&imx8_soc_driver);
+}
+
+module_init(imx8_soc_init);
+module_exit(imx8_soc_exit);
-- 
2.7.4