[PATCH v5 1/4] dt-bindings: soc: imx8m: add DT Binding doc for soc unique ID

[PATCH v5 1/4] dt-bindings: soc: imx8m: add DT Binding doc for soc unique ID

[Alice Guo]

Add DT Binding doc for the Unique ID of i.MX 8M series.

Signed-off-by: Alice Guo <alice.guo@nxp.com>
---

v2: remove the subject prefix "LF-2571-1"
v3: put it into Documentation/devicetree/bindings/arm/fsl.yaml
    modify the description of nvmem-cells
    use "make ARCH=arm64 dtbs_check" to test it and fix errors
v4: use allOf to limit new version DTS files for i.MX8M to include
    "fsl,imx8mm/n/p/q-soc", nvmem-cells and nvmem-cells-names
v5: correct the error of using allOf

 .../devicetree/bindings/arm/fsl.yaml          | 47 +++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/fsl.yaml b/Documentation/devicetree/bindings/arm/fsl.yaml
index 67980dcef66d..7132ffd41abb 100644
--- a/Documentation/devicetree/bindings/arm/fsl.yaml
+++ b/Documentation/devicetree/bindings/arm/fsl.yaml
@@ -918,6 +918,53 @@ properties:
               - fsl,s32v234-evb           # S32V234-EVB2 Customer Evaluation Board
           - const: fsl,s32v234

+  soc:
+    type: object
+    properties:
+      compatible:
+        oneOf:
+          - description: new version compatible for i.MX8M SoCs
+            items:
+              - enum:
+                  - fsl,imx8mm-soc
+                  - fsl,imx8mn-soc
+                  - fsl,imx8mp-soc
+                  - fsl,imx8mq-soc
+              - const: simple-bus
+
+          - description: old version compatible for i.MX8M SoCs
+            items:
+              - const: simple-bus
+
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - fsl,imx8mm
+              - fsl,imx8mn
+              - fsl,imx8mp
+              - fsl,imx8mq
+
+    then:
+      patternProperties:
+        "^soc@[0-9a-f]+$":
+          properties:
+            compatible:
+              items:
+                - enum:
+                    - fsl,imx8mm-soc
+                    - fsl,imx8mn-soc
+                    - fsl,imx8mp-soc
+                    - fsl,imx8mq-soc
+                - const: simple-bus
+
+          required:
+            - compatible
+            - nvmem-cells
+            - nvmem-cell-names
+
 additionalProperties: true

 ...
--
2.17.1

[PATCH v5 2/4] arm64: dts: imx8m: add SoC ID compatible

[Alice Guo]

Add compatible string to .dtsi files for binding of imx8_soc_info and
device.

v2: remove the subject prefix "LF-2571-2"
v3: none
v4: change subject and commit message, add Reviewed-by

Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Alice Guo <alice.guo@nxp.com>
---

v2: remove the subject prefix "LF-2571-2"
v3: none
v4: change subject and commit message, add Reviewed-by
v5: none

 arch/arm64/boot/dts/freescale/imx8mm.dtsi | 2 +-
 arch/arm64/boot/dts/freescale/imx8mn.dtsi | 2 +-
 arch/arm64/boot/dts/freescale/imx8mp.dtsi | 2 +-
 arch/arm64/boot/dts/freescale/imx8mq.dtsi | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/boot/dts/freescale/imx8mm.dtsi b/arch/arm64/boot/dts/freescale/imx8mm.dtsi
index c824f2615fe8..d457ce815e68 100644
--- a/arch/arm64/boot/dts/freescale/imx8mm.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mm.dtsi
@@ -257,7 +257,7 @@
 	};

 	soc@0 {
-		compatible = "simple-bus";
+		compatible = "fsl,imx8mm-soc", "simple-bus";
 		#address-cells = <1>;
 		#size-cells = <1>;
 		ranges = <0x0 0x0 0x0 0x3e000000>;
diff --git a/arch/arm64/boot/dts/freescale/imx8mn.dtsi b/arch/arm64/boot/dts/freescale/imx8mn.dtsi
index a06d2a6268e6..6d3a809a00fd 100644
--- a/arch/arm64/boot/dts/freescale/imx8mn.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mn.dtsi
@@ -241,7 +241,7 @@
 	};

 	soc@0 {
-		compatible = "simple-bus";
+		compatible = "fsl,imx8mn-soc", "simple-bus";
 		#address-cells = <1>;
 		#size-cells = <1>;
 		ranges = <0x0 0x0 0x0 0x3e000000>;
diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
index ecccfbb4f5ad..ec6ac523ecfc 100644
--- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
@@ -218,7 +218,7 @@
 	};

 	soc@0 {
-		compatible = "simple-bus";
+		compatible = "fsl,imx8mp-soc", "simple-bus";
 		#address-cells = <1>;
 		#size-cells = <1>;
 		ranges = <0x0 0x0 0x0 0x3e000000>;
diff --git a/arch/arm64/boot/dts/freescale/imx8mq.dtsi b/arch/arm64/boot/dts/freescale/imx8mq.dtsi
index a841a023e8e0..9b6d9307e5d7 100644
--- a/arch/arm64/boot/dts/freescale/imx8mq.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mq.dtsi
@@ -286,7 +286,7 @@
 	};

 	soc@0 {
-		compatible = "simple-bus";
+		compatible = "fsl,imx8mq-soc", "simple-bus";
 		#address-cells = <1>;
 		#size-cells = <1>;
 		ranges = <0x0 0x0 0x0 0x3e000000>;
--
2.17.1

[PATCH v5 3/4] arm64: dts: imx8m: add NVMEM provider and consumer to read soc unique ID

[Alice Guo]

In order to be able to use NVMEM APIs to read soc unique ID, add the
nvmem data cell and name for nvmem-cells to the "soc" node, and add a
nvmem node which provides soc unique ID to efuse@30350000.

Signed-off-by: Alice Guo <alice.guo@nxp.com>
---

v2: remove the subject prefix "LF-2571-3"
v3: convert register addresses and sizes to hex
v4: delete "stuff" in subject and commit message, add detailed
    description
v5: change underscore of device node to hyphen

 arch/arm64/boot/dts/freescale/imx8mm.dtsi | 6 ++++++
 arch/arm64/boot/dts/freescale/imx8mn.dtsi | 6 ++++++
 arch/arm64/boot/dts/freescale/imx8mp.dtsi | 6 ++++++
 arch/arm64/boot/dts/freescale/imx8mq.dtsi | 6 ++++++
 4 files changed, 24 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/imx8mm.dtsi b/arch/arm64/boot/dts/freescale/imx8mm.dtsi
index d457ce815e68..9bee6f1889a4 100644
--- a/arch/arm64/boot/dts/freescale/imx8mm.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mm.dtsi
@@ -261,6 +261,8 @@
 		#address-cells = <1>;
 		#size-cells = <1>;
 		ranges = <0x0 0x0 0x0 0x3e000000>;
+		nvmem-cells = <&imx8mm_uid>;
+		nvmem-cell-names = "soc_unique_id";

 		aips1: bus@30000000 {
 			compatible = "fsl,aips-bus", "simple-bus";
@@ -518,6 +520,10 @@
 				#address-cells = <1>;
 				#size-cells = <1>;

+				imx8mm_uid: unique-id@410 {
+					reg = <0x4 0x8>;
+				};
+
 				cpu_speed_grade: speed-grade@10 {
 					reg = <0x10 4>;
 				};
diff --git a/arch/arm64/boot/dts/freescale/imx8mn.dtsi b/arch/arm64/boot/dts/freescale/imx8mn.dtsi
index 6d3a809a00fd..2edfde1119b8 100644
--- a/arch/arm64/boot/dts/freescale/imx8mn.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mn.dtsi
@@ -245,6 +245,8 @@
 		#address-cells = <1>;
 		#size-cells = <1>;
 		ranges = <0x0 0x0 0x0 0x3e000000>;
+		nvmem-cells = <&imx8mn_uid>;
+		nvmem-cell-names = "soc_unique_id";

 		aips1: bus@30000000 {
 			compatible = "fsl,aips-bus", "simple-bus";
@@ -388,6 +390,10 @@
 				#address-cells = <1>;
 				#size-cells = <1>;

+				imx8mn_uid: unique-id@410 {
+					reg = <0x4 0x8>;
+				};
+
 				cpu_speed_grade: speed-grade@10 {
 					reg = <0x10 4>;
 				};
diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
index ec6ac523ecfc..9401e92f1c84 100644
--- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
@@ -222,6 +222,8 @@
 		#address-cells = <1>;
 		#size-cells = <1>;
 		ranges = <0x0 0x0 0x0 0x3e000000>;
+		nvmem-cells = <&imx8mp_uid>;
+		nvmem-cell-names = "soc_unique_id";

 		aips1: bus@30000000 {
 			compatible = "fsl,aips-bus", "simple-bus";
@@ -328,6 +330,10 @@
 				#address-cells = <1>;
 				#size-cells = <1>;

+				imx8mp_uid: unique-id@420 {
+					reg = <0x8 0x8>;
+				};
+
 				cpu_speed_grade: speed-grade@10 {
 					reg = <0x10 4>;
 				};
diff --git a/arch/arm64/boot/dts/freescale/imx8mq.dtsi b/arch/arm64/boot/dts/freescale/imx8mq.dtsi
index 9b6d9307e5d7..a2a885f1a07a 100644
--- a/arch/arm64/boot/dts/freescale/imx8mq.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mq.dtsi
@@ -291,6 +291,8 @@
 		#size-cells = <1>;
 		ranges = <0x0 0x0 0x0 0x3e000000>;
 		dma-ranges = <0x40000000 0x0 0x40000000 0xc0000000>;
+		nvmem-cells = <&imx8mq_uid>;
+		nvmem-cell-names = "soc_unique_id";

 		bus@30000000 { /* AIPS1 */
 			compatible = "fsl,aips-bus", "simple-bus";
@@ -555,6 +557,10 @@
 				#address-cells = <1>;
 				#size-cells = <1>;

+				imx8mq_uid: soc-uid@410 {
+					reg = <0x4 0x8>;
+				};
+
 				cpu_speed_grade: speed-grade@10 {
 					reg = <0x10 4>;
 				};
--
2.17.1

[PATCH v5 4/4] soc: imx8m: change to use platform driver

[Alice Guo]

Directly reading ocotp register depends on that bootloader enables ocotp
clk, which is not always effective, so change to use nvmem API. Using
nvmem API requires to support driver defer probe and thus change
soc-imx8m.c to use platform driver.

The other reason is that directly reading ocotp register causes kexec
kernel hang because the 1st kernel running will disable unused clks
after kernel boots up, and then ocotp clk will be disabled even if
bootloader enables it. When kexec kernel, ocotp clk needs to be enabled
before reading ocotp registers, and nvmem API with platform driver
supported can accomplish this.

Signed-off-by: Alice Guo <alice.guo@nxp.com>
---

v2: remove the subject prefix "LF-2571-4"
v3: Keep the original way which uses device_initcall to read soc unique
    ID, and add the other way which uses module_platform_driver and
    nvmem API, so that it will not break the old version DTBs.
v4: delete "__maybe_unused"
    delete MODULE_DEVICE_TABLE(of, imx8m_soc_match);
    rename match table, "fsl,imx8mm/n/q/p" is actually a machine
compabile and "fsl,imx8mm/n/q/p-soc" is a compabile of soc@0
    delete "flag" and change to determine whether the pointer is NULL
    ues of_find_matching_node_and_match()
    delete of_match_ptr()
v5: add cleanup part "of_node_put"
    add note to explain that why device_initcall still exists

 drivers/soc/imx/soc-imx8m.c | 87 ++++++++++++++++++++++++++++++++-----
 1 file changed, 75 insertions(+), 12 deletions(-)

diff --git a/drivers/soc/imx/soc-imx8m.c b/drivers/soc/imx/soc-imx8m.c
index cc57a384d74d..250530177920 100644
--- a/drivers/soc/imx/soc-imx8m.c
+++ b/drivers/soc/imx/soc-imx8m.c
@@ -5,6 +5,8 @@

 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
 #include <linux/of_address.h>
 #include <linux/slab.h>
 #include <linux/sys_soc.h>
@@ -29,7 +31,7 @@

 struct imx8_soc_data {
 	char *name;
-	u32 (*soc_revision)(void);
+	u32 (*soc_revision)(struct device *dev);
 };

 static u64 soc_uid;
@@ -50,7 +52,7 @@ 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 u32 __init imx8mq_soc_revision(struct device *dev)
 {
 	struct device_node *np;
 	void __iomem *ocotp_base;
@@ -75,9 +77,20 @@ static u32 __init imx8mq_soc_revision(void)
 			rev = REV_B1;
 	}

-	soc_uid = readl_relaxed(ocotp_base + OCOTP_UID_HIGH);
-	soc_uid <<= 32;
-	soc_uid |= readl_relaxed(ocotp_base + OCOTP_UID_LOW);
+	if (dev) {
+		int ret = 0;
+
+		ret = nvmem_cell_read_u64(dev, "soc_unique_id", &soc_uid);
+		if (ret) {
+			iounmap(ocotp_base);
+			of_node_put(np);
+			return ret;
+		}
+	} else {
+		soc_uid = readl_relaxed(ocotp_base + OCOTP_UID_HIGH);
+		soc_uid <<= 32;
+		soc_uid |= readl_relaxed(ocotp_base + OCOTP_UID_LOW);
+	}

 	iounmap(ocotp_base);
 	of_node_put(np);
@@ -107,7 +120,7 @@ static void __init imx8mm_soc_uid(void)
 	of_node_put(np);
 }

-static u32 __init imx8mm_soc_revision(void)
+static u32 __init imx8mm_soc_revision(struct device *dev)
 {
 	struct device_node *np;
 	void __iomem *anatop_base;
@@ -125,7 +138,15 @@ static u32 __init imx8mm_soc_revision(void)
 	iounmap(anatop_base);
 	of_node_put(np);

-	imx8mm_soc_uid();
+	if (dev) {
+		int ret = 0;
+
+		ret = nvmem_cell_read_u64(dev, "soc_unique_id", &soc_uid);
+		if (ret)
+			return ret;
+	} else {
+		imx8mm_soc_uid();
+	}

 	return rev;
 }
@@ -150,7 +171,7 @@ static const struct imx8_soc_data imx8mp_soc_data = {
 	.soc_revision = imx8mm_soc_revision,
 };

-static __maybe_unused const struct of_device_id imx8_soc_match[] = {
+static const struct of_device_id imx8_machine_match[] = {
 	{ .compatible = "fsl,imx8mq", .data = &imx8mq_soc_data, },
 	{ .compatible = "fsl,imx8mm", .data = &imx8mm_soc_data, },
 	{ .compatible = "fsl,imx8mn", .data = &imx8mn_soc_data, },
@@ -158,12 +179,20 @@ static __maybe_unused const struct of_device_id imx8_soc_match[] = {
 	{ }
 };

+static const struct of_device_id imx8_soc_match[] = {
+	{ .compatible = "fsl,imx8mq-soc", .data = &imx8mq_soc_data, },
+	{ .compatible = "fsl,imx8mm-soc", .data = &imx8mm_soc_data, },
+	{ .compatible = "fsl,imx8mn-soc", .data = &imx8mn_soc_data, },
+	{ .compatible = "fsl,imx8mp-soc", .data = &imx8mp_soc_data, },
+	{ }
+};
+
 #define imx8_revision(soc_rev) \
 	soc_rev ? \
 	kasprintf(GFP_KERNEL, "%d.%d", (soc_rev >> 4) & 0xf,  soc_rev & 0xf) : \
 	"unknown"

-static int __init imx8_soc_init(void)
+static int imx8_soc_info(struct platform_device *pdev)
 {
 	struct soc_device_attribute *soc_dev_attr;
 	struct soc_device *soc_dev;
@@ -182,7 +211,10 @@ static int __init imx8_soc_init(void)
 	if (ret)
 		goto free_soc;

-	id = of_match_node(imx8_soc_match, of_root);
+	if (pdev)
+		id = of_match_node(imx8_soc_match, pdev->dev.of_node);
+	else
+		id = of_match_node(imx8_machine_match, of_root);
 	if (!id) {
 		ret = -ENODEV;
 		goto free_soc;
@@ -191,8 +223,16 @@ 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) {
+			if (pdev) {
+				soc_rev = data->soc_revision(&pdev->dev);
+				ret = soc_rev;
+				if (ret < 0)
+					goto free_soc;
+			} else {
+				soc_rev = data->soc_revision(NULL);
+			}
+		}
 	}

 	soc_dev_attr->revision = imx8_revision(soc_rev);
@@ -230,4 +270,27 @@ static int __init imx8_soc_init(void)
 	kfree(soc_dev_attr);
 	return ret;
 }
+
+/* Retain device_initcall is for backward compatibility with DTS. */
+static int __init imx8_soc_init(void)
+{
+	int ret = 0;
+
+	if (of_find_matching_node_and_match(NULL, imx8_soc_match, NULL))
+		return 0;
+
+	ret = imx8_soc_info(NULL);
+	return ret;
+}
 device_initcall(imx8_soc_init);
+
+static struct platform_driver imx8_soc_info_driver = {
+	.probe = imx8_soc_info,
+	.driver = {
+		.name = "imx8_soc_info",
+		.of_match_table = imx8_soc_match,
+	},
+};
+
+module_platform_driver(imx8_soc_info_driver);
+MODULE_LICENSE("GPL v2");
--
2.17.1

Re: [PATCH v5 1/4] dt-bindings: soc: imx8m: add DT Binding doc for soc unique ID

[Krzysztof Kozlowski]

On Mon, Nov 23, 2020 at 05:51:05PM +0800, Alice Guo wrote:
> Add DT Binding doc for the Unique ID of i.MX 8M series.
> 
> Signed-off-by: Alice Guo <alice.guo@nxp.com>
> ---
> 
> v2: remove the subject prefix "LF-2571-1"
> v3: put it into Documentation/devicetree/bindings/arm/fsl.yaml
>     modify the description of nvmem-cells
>     use "make ARCH=arm64 dtbs_check" to test it and fix errors
> v4: use allOf to limit new version DTS files for i.MX8M to include
>     "fsl,imx8mm/n/p/q-soc", nvmem-cells and nvmem-cells-names
> v5: correct the error of using allOf
> 
>  .../devicetree/bindings/arm/fsl.yaml          | 47 +++++++++++++++++++
>  1 file changed, 47 insertions(+)
> 

Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>

Best regards,
Krzysztof

Re: [PATCH v5 2/4] arm64: dts: imx8m: add SoC ID compatible

[Krzysztof Kozlowski]

On Mon, Nov 23, 2020 at 05:51:06PM +0800, Alice Guo wrote:
> Add compatible string to .dtsi files for binding of imx8_soc_info and
> device.
> 
> v2: remove the subject prefix "LF-2571-2"
> v3: none
> v4: change subject and commit message, add Reviewed-by

You have here duplicated changelog. Leave only the one under '---'.
Thanks!


Best regards,
Krzysztof

> 
> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
> Signed-off-by: Alice Guo <alice.guo@nxp.com>
> ---
> 
> v2: remove the subject prefix "LF-2571-2"
> v3: none
> v4: change subject and commit message, add Reviewed-by
> v5: none
> 
>  arch/arm64/boot/dts/freescale/imx8mm.dtsi | 2 +-
>  arch/arm64/boot/dts/freescale/imx8mn.dtsi | 2 +-
>  arch/arm64/boot/dts/freescale/imx8mp.dtsi | 2 +-
>  arch/arm64/boot/dts/freescale/imx8mq.dtsi | 2 +-
>  4 files changed, 4 insertions(+), 4 deletions(-)
> 

Re: [PATCH v5 3/4] arm64: dts: imx8m: add NVMEM provider and consumer to read soc unique ID

[Krzysztof Kozlowski]

On Mon, Nov 23, 2020 at 05:51:07PM +0800, Alice Guo wrote:
> In order to be able to use NVMEM APIs to read soc unique ID, add the
> nvmem data cell and name for nvmem-cells to the "soc" node, and add a
> nvmem node which provides soc unique ID to efuse@30350000.
> 
> Signed-off-by: Alice Guo <alice.guo@nxp.com>
> ---
> 

Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>

Best regards,
Krzysztof

Re: [PATCH v5 4/4] soc: imx8m: change to use platform driver

[Krzysztof Kozlowski]

On Mon, Nov 23, 2020 at 05:51:08PM +0800, Alice Guo wrote:
> Directly reading ocotp register depends on that bootloader enables ocotp
> clk, which is not always effective, so change to use nvmem API. Using
> nvmem API requires to support driver defer probe and thus change
> soc-imx8m.c to use platform driver.
> 
> The other reason is that directly reading ocotp register causes kexec
> kernel hang because the 1st kernel running will disable unused clks
> after kernel boots up, and then ocotp clk will be disabled even if
> bootloader enables it. When kexec kernel, ocotp clk needs to be enabled
> before reading ocotp registers, and nvmem API with platform driver
> supported can accomplish this.
> 
> Signed-off-by: Alice Guo <alice.guo@nxp.com>
> ---
> 

Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>

Best regards,
Krzysztof