[PATCH 0/8] Introduce UCLASS_SOC

[PATCH 0/8] Introduce UCLASS_SOC

[Dave Gerlach]

Hi,

This patch series introduces UCLASS_SOC to be used for SOC identification and
attribute matching based on SoC ID info. This allows drivers to be
provided for SoCs to retrieve SoC identifying information and also for matching
device attributes for selecting SoC specific data. This is intended to be a
counterpart to the soc-device framework in the Linux kernel.

I started with attempts to extend either UCLASS_CPU and UCLASS_BOARD to provide
equivalent functionality, but UCLASS_CPU is focused specifically on processing
units, of which multiples can exist heterogeneously in a system, and
UCLASS_BOARD is focused on indentifying things connected to an SoC dynamically.
Rather than try to force this into the existing UCLASS's, a new UCLASS seemed
appropriate to provide same services as the soc-device functionality
in the kernel.

This is useful for other device drivers that may need different
parameters or quirks enabled depending on the specific device variant or
revision in use.

Additionally, this introduces a user of UCLASS_SOC, soc_ti_k3, which provides
SoC identifying information for K3 SoCs which can be used directly, for
print_cpuinfo, and for selecting SoC specific data using soc_device_match.

Regards,
Dave

Dave Gerlach (8):
  dm: soc: Introduce UCLASS_SOC for SOC ID and attribute matching
  test: Add tests for SOC uclass
  dm: soc: Introduce soc_ti_k3 driver for TI K3 SoCs
  arm: dts: k3-am65-wakeup: Introduce chipid node
  arm: dts: k3-j721e-mcu-wakeup: Introduce chipid node
  configs: am65x_evm: Enable CONFIG_SOC_DEVICE and
    CONFIG_SOC_DEVICE_TI_K3
  configs: j721e_evm: Enable CONFIG_SOC_DEVICE and
    CONFIG_SOC_DEVICE_TI_K3
  arm: mach-k3: Use SOC driver for device identification

 arch/arm/dts/k3-am65-wakeup.dtsi              |   5 +
 arch/arm/dts/k3-am654-base-board-u-boot.dtsi  |   4 +
 .../k3-j721e-common-proc-board-u-boot.dtsi    |   4 +
 arch/arm/dts/k3-j721e-mcu-wakeup.dtsi         |   5 +
 arch/arm/mach-k3/common.c                     |  48 +++----
 arch/arm/mach-k3/include/mach/hardware.h      |   1 -
 arch/sandbox/dts/test.dts                     |   4 +
 configs/am65x_evm_a53_defconfig               |   2 +
 configs/am65x_evm_r5_defconfig                |   2 +
 configs/am65x_hs_evm_a53_defconfig            |   2 +
 configs/am65x_hs_evm_r5_defconfig             |   2 +
 configs/j721e_evm_a72_defconfig               |   2 +
 configs/j721e_evm_r5_defconfig                |   2 +
 configs/j721e_hs_evm_a72_defconfig            |   2 +
 configs/j721e_hs_evm_r5_defconfig             |   2 +
 configs/sandbox64_defconfig                   |   1 +
 configs/sandbox_defconfig                     |   1 +
 configs/sandbox_flattree_defconfig            |   1 +
 configs/sandbox_spl_defconfig                 |   1 +
 drivers/soc/Kconfig                           |  16 +++
 drivers/soc/Makefile                          |   3 +
 drivers/soc/soc-uclass.c                      | 102 ++++++++++++++
 drivers/soc/soc_sandbox.c                     |  56 ++++++++
 drivers/soc/soc_ti_k3.c                       | 124 ++++++++++++++++
 include/dm/uclass-id.h                        |   1 +
 include/soc.h                                 | 132 ++++++++++++++++++
 test/dm/Makefile                              |   1 +
 test/dm/soc.c                                 | 120 ++++++++++++++++
 28 files changed, 616 insertions(+), 30 deletions(-)
 create mode 100644 drivers/soc/soc-uclass.c
 create mode 100644 drivers/soc/soc_sandbox.c
 create mode 100644 drivers/soc/soc_ti_k3.c
 create mode 100644 include/soc.h
 create mode 100644 test/dm/soc.c

-- 
2.20.1

[PATCH 1/8] dm: soc: Introduce UCLASS_SOC for SOC ID and attribute matching

[Dave Gerlach]

Introduce UCLASS_SOC to be used for SOC identification and attribute
matching based on the SoC ID info. This allows drivers to be provided
for SoCs to retrieve SoC identifying information and also for matching
device attributes for selecting SoC specific data.

This is useful for other device drivers that may need different
parameters or quirks enabled depending on the specific device variant in
use.

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
---
 drivers/soc/Kconfig      |   9 +++
 drivers/soc/Makefile     |   1 +
 drivers/soc/soc-uclass.c | 102 ++++++++++++++++++++++++++++++
 include/dm/uclass-id.h   |   1 +
 include/soc.h            | 132 +++++++++++++++++++++++++++++++++++++++
 5 files changed, 245 insertions(+)
 create mode 100644 drivers/soc/soc-uclass.c
 create mode 100644 include/soc.h

diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index 7b4e4d613088..e715dfd01712 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -1,5 +1,14 @@
 menu "SOC (System On Chip) specific Drivers"
 
+config SOC_DEVICE
+	bool "Enable SoC Device ID drivers using Driver Model"
+	help
+	  This allows drivers to be provided for SoCs to help in identifying
+	  the SoC in use and matching SoC attributes for selecting SoC
+	  specific data. This is useful for other device drivers that may
+	  need different parameters or quirks enabled depending on the
+	  specific device variant in use.
+
 source "drivers/soc/ti/Kconfig"
 
 endmenu
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index ce253b7aa886..1c09a8465670 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -3,3 +3,4 @@
 # Makefile for the U-Boot SOC specific device drivers.
 
 obj-$(CONFIG_SOC_TI) += ti/
+obj-$(CONFIG_SOC_DEVICE) += soc-uclass.o
diff --git a/drivers/soc/soc-uclass.c b/drivers/soc/soc-uclass.c
new file mode 100644
index 000000000000..22f89514ed7d
--- /dev/null
+++ b/drivers/soc/soc-uclass.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2020 - Texas Instruments Incorporated - http://www.ti.com/
+ *	Dave Gerlach <d-gerlach@ti.com>
+ */
+
+#include <common.h>
+#include <soc.h>
+#include <dm.h>
+#include <errno.h>
+#include <dm/lists.h>
+#include <dm/root.h>
+
+int soc_get(struct udevice **devp)
+{
+	return uclass_first_device_err(UCLASS_SOC, devp);
+}
+
+int soc_get_machine(struct udevice *dev, char *buf, int size)
+{
+	struct soc_ops *ops = soc_get_ops(dev);
+
+	if (!ops->get_machine)
+		return -ENOSYS;
+
+	return ops->get_machine(dev, buf, size);
+}
+
+int soc_get_family(struct udevice *dev, char *buf, int size)
+{
+	struct soc_ops *ops = soc_get_ops(dev);
+
+	if (!ops->get_family)
+		return -ENOSYS;
+
+	return ops->get_family(dev, buf, size);
+}
+
+int soc_get_revision(struct udevice *dev, char *buf, int size)
+{
+	struct soc_ops *ops = soc_get_ops(dev);
+
+	if (!ops->get_revision)
+		return -ENOSYS;
+
+	return ops->get_revision(dev, buf, size);
+}
+
+const struct soc_device_attribute *
+soc_device_match(const struct soc_device_attribute *matches)
+{
+	bool match;
+	struct udevice *soc;
+	char str[SOC_MAX_STR_SIZE];
+
+	if (!matches)
+		return NULL;
+
+	if (soc_get(&soc))
+		return NULL;
+
+	while (1) {
+		if (!(matches->machine || matches->family ||
+		      matches->revision))
+			break;
+
+		match = true;
+
+		if (matches->machine) {
+			if (!soc_get_machine(soc, str, SOC_MAX_STR_SIZE)) {
+				if (strcmp(matches->machine, str))
+					match = false;
+			}
+		}
+
+		if (matches->family) {
+			if (!soc_get_family(soc, str, SOC_MAX_STR_SIZE)) {
+				if (strcmp(matches->family, str))
+					match = false;
+			}
+		}
+
+		if (matches->revision) {
+			if (!soc_get_revision(soc, str, SOC_MAX_STR_SIZE)) {
+				if (strcmp(matches->revision, str))
+					match = false;
+			}
+		}
+
+		if (match)
+			return matches;
+
+		matches++;
+	}
+
+	return NULL;
+}
+
+UCLASS_DRIVER(soc) = {
+	.id		= UCLASS_SOC,
+	.name		= "soc",
+};
diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index 7837d459f18c..690a8ed4df49 100644
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -97,6 +97,7 @@ enum uclass_id {
 	UCLASS_SERIAL,		/* Serial UART */
 	UCLASS_SIMPLE_BUS,	/* Bus with child devices */
 	UCLASS_SMEM,		/* Shared memory interface */
+	UCLASS_SOC,		/* SOC Device */
 	UCLASS_SOUND,		/* Playing simple sounds */
 	UCLASS_SPI,		/* SPI bus */
 	UCLASS_SPI_FLASH,	/* SPI flash */
diff --git a/include/soc.h b/include/soc.h
new file mode 100644
index 000000000000..98e3cc000198
--- /dev/null
+++ b/include/soc.h
@@ -0,0 +1,132 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * (C) Copyright 2020 - Texas Instruments Incorporated - http://www.ti.com/
+ *	Dave Gerlach <d-gerlach@ti.com>
+ */
+
+#ifndef __SOC_H
+#define __SOC_H
+
+#define SOC_MAX_STR_SIZE	128
+
+struct soc_device_attribute {
+	const char *machine;
+	const char *family;
+	const char *revision;
+	const void *data;
+};
+
+#ifdef CONFIG_SOC_DEVICE
+struct soc_ops {
+	/**
+	 * get_machine() - Get machine name of an SOC
+	 *
+	 * @dev:	Device to check (UCLASS_SOC)
+	 * @buf:	Buffer to place string
+	 * @size:	Size of string space
+	 * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
+	 */
+	int (*get_machine)(struct udevice *dev, char *buf, int size);
+
+	/**
+	 * get_revision() - Get revision name of a SOC
+	 *
+	 * @dev:	Device to check (UCLASS_SOC)
+	 * @buf:	Buffer to place string
+	 * @size:	Size of string space
+	 * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
+	 */
+	int (*get_revision)(struct udevice *dev, char *buf, int size);
+
+	/**
+	 * get_family() - Get family name of an SOC
+	 *
+	 * @dev:	Device to check (UCLASS_SOC)
+	 * @buf:	Buffer to place string
+	 * @size:	Size of string space
+	 * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
+	 */
+	int (*get_family)(struct udevice *dev, char *buf, int size);
+};
+
+#define soc_get_ops(dev)        ((struct soc_ops *)(dev)->driver->ops)
+
+/**
+ * soc_get() - Return the soc device for the soc in use.
+ * @devp: Pointer to structure to receive the soc device.
+ *
+ * Since there can only be at most one SOC instance, the API can supply a
+ * function that returns the unique device.
+ *
+ * Return: 0 if OK, -ve on error.
+ */
+int soc_get(struct udevice **devp);
+
+/**
+ * soc_get_machine() - Get machine name of an SOC
+ * @dev:	Device to check (UCLASS_SOC)
+ * @buf:	Buffer to place string
+ * @size:	Size of string space
+ *
+ * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
+ */
+int soc_get_machine(struct udevice *dev, char *buf, int size);
+
+/**
+ * soc_get_revision() - Get revision name of an SOC
+ * @dev:	Device to check (UCLASS_SOC)
+ * @buf:	Buffer to place string
+ * @size:	Size of string space
+ *
+ * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
+ */
+int soc_get_revision(struct udevice *dev, char *buf, int size);
+
+/**
+ * soc_get_family() - Get family name of an SOC
+ * @dev:	Device to check (UCLASS_SOC)
+ * @buf:	Buffer to place string
+ * @size:	Size of string space
+ *
+ * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
+ */
+int soc_get_family(struct udevice *dev, char *buf, int size);
+
+/**
+ * soc_device_match() - Return match from an array of soc_device_attribute
+ * @matches:	Array with any combination of family, revision or machine set
+ *
+ * Return: Pointer to struct from matches array with set attributes matching
+ *	   those provided by the soc device.
+ */
+const struct soc_device_attribute *
+soc_device_match(const struct soc_device_attribute *matches);
+
+#else
+static inline int soc_get(struct udevice **devp)
+{
+	return -ENOSYS;
+}
+
+static inline int soc_get_machine(struct udevice *dev, char *buf, int size)
+{
+	return -ENOSYS;
+}
+
+static inline int soc_get_revision(struct udevice *dev, char *buf, int size)
+{
+	return -ENOSYS;
+}
+
+static inline int soc_get_family(struct udevice *dev, char *buf, int size)
+{
+	return -ENOSYS;
+}
+
+static inline const struct soc_device_attribute *
+soc_device_match(const struct soc_device_attribute *matches)
+{
+	return NULL;
+}
+#endif
+#endif /* _SOC_H */
-- 
2.20.1

[PATCH 2/8] test: Add tests for SOC uclass

[Dave Gerlach]

Add a sandbox SOC driver, and some tests for the SOC uclass.

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
---
 arch/sandbox/dts/test.dts          |   4 +
 configs/sandbox64_defconfig        |   1 +
 configs/sandbox_defconfig          |   1 +
 configs/sandbox_flattree_defconfig |   1 +
 configs/sandbox_spl_defconfig      |   1 +
 drivers/soc/Makefile               |   1 +
 drivers/soc/soc_sandbox.c          |  56 ++++++++++++++
 test/dm/Makefile                   |   1 +
 test/dm/soc.c                      | 120 +++++++++++++++++++++++++++++
 9 files changed, 186 insertions(+)
 create mode 100644 drivers/soc/soc_sandbox.c
 create mode 100644 test/dm/soc.c

diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
index 5ce5e2847642..20404c4a0ce9 100644
--- a/arch/sandbox/dts/test.dts
+++ b/arch/sandbox/dts/test.dts
@@ -492,6 +492,10 @@
 		};
 	};
 
+	chipid: chipid {
+		compatible = "sandbox,soc";
+	};
+
 	i2s: i2s {
 		compatible = "sandbox,i2s";
 		#sound-dai-cells = <1>;
diff --git a/configs/sandbox64_defconfig b/configs/sandbox64_defconfig
index a3f049e124e1..3ded31f4a9a7 100644
--- a/configs/sandbox64_defconfig
+++ b/configs/sandbox64_defconfig
@@ -114,6 +114,7 @@ CONFIG_LED_GPIO=y
 CONFIG_DM_MAILBOX=y
 CONFIG_SANDBOX_MBOX=y
 CONFIG_MISC=y
+CONFIG_SOC_DEVICE=y
 CONFIG_CROS_EC=y
 CONFIG_CROS_EC_I2C=y
 CONFIG_CROS_EC_LPC=y
diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig
index 5b7569319b73..b19f337f3f0c 100644
--- a/configs/sandbox_defconfig
+++ b/configs/sandbox_defconfig
@@ -133,6 +133,7 @@ CONFIG_LED_GPIO=y
 CONFIG_DM_MAILBOX=y
 CONFIG_SANDBOX_MBOX=y
 CONFIG_MISC=y
+CONFIG_SOC_DEVICE=y
 CONFIG_CROS_EC=y
 CONFIG_CROS_EC_I2C=y
 CONFIG_CROS_EC_LPC=y
diff --git a/configs/sandbox_flattree_defconfig b/configs/sandbox_flattree_defconfig
index 21f9047046a3..b889ecb058c8 100644
--- a/configs/sandbox_flattree_defconfig
+++ b/configs/sandbox_flattree_defconfig
@@ -99,6 +99,7 @@ CONFIG_LED_GPIO=y
 CONFIG_DM_MAILBOX=y
 CONFIG_SANDBOX_MBOX=y
 CONFIG_MISC=y
+CONFIG_SOC_DEVICE=y
 CONFIG_CROS_EC=y
 CONFIG_CROS_EC_I2C=y
 CONFIG_CROS_EC_LPC=y
diff --git a/configs/sandbox_spl_defconfig b/configs/sandbox_spl_defconfig
index fc8b26e88cfe..45cb9e78d769 100644
--- a/configs/sandbox_spl_defconfig
+++ b/configs/sandbox_spl_defconfig
@@ -118,6 +118,7 @@ CONFIG_LED_GPIO=y
 CONFIG_DM_MAILBOX=y
 CONFIG_SANDBOX_MBOX=y
 CONFIG_MISC=y
+CONFIG_SOC_DEVICE=y
 CONFIG_CROS_EC=y
 CONFIG_CROS_EC_I2C=y
 CONFIG_CROS_EC_LPC=y
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index 1c09a8465670..649e92b3906d 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -4,3 +4,4 @@
 
 obj-$(CONFIG_SOC_TI) += ti/
 obj-$(CONFIG_SOC_DEVICE) += soc-uclass.o
+obj-$(CONFIG_SANDBOX) += soc_sandbox.o
diff --git a/drivers/soc/soc_sandbox.c b/drivers/soc/soc_sandbox.c
new file mode 100644
index 000000000000..5c82ad84fc21
--- /dev/null
+++ b/drivers/soc/soc_sandbox.c
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Sandbox driver for the SOC uclass
+ *
+ * (C) Copyright 2020 - Texas Instruments Incorporated - http://www.ti.com/
+ * Dave Gerlach <d-gerlach@ti.com>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <soc.h>
+
+int soc_sandbox_get_family(struct udevice *dev, char *buf, int size)
+{
+	snprintf(buf, size, "SANDBOX1xx");
+
+	return 0;
+}
+
+int soc_sandbox_get_machine(struct udevice *dev, char *buf, int size)
+{
+	snprintf(buf, size, "SANDBOX123");
+
+	return 0;
+}
+
+int soc_sandbox_get_revision(struct udevice *dev, char *buf, int size)
+{
+	snprintf(buf, size, "1.0");
+
+	return 0;
+}
+
+static const struct soc_ops soc_sandbox_ops = {
+	.get_family = soc_sandbox_get_family,
+	.get_revision = soc_sandbox_get_revision,
+	.get_machine = soc_sandbox_get_machine,
+};
+
+int soc_sandbox_probe(struct udevice *dev)
+{
+	return 0;
+}
+
+static const struct udevice_id soc_sandbox_ids[] = {
+	{ .compatible = "sandbox,soc" },
+	{ }
+};
+
+U_BOOT_DRIVER(soc_sandbox) = {
+	.name           = "soc_sandbox",
+	.id             = UCLASS_SOC,
+	.ops		= &soc_sandbox_ops,
+	.of_match       = soc_sandbox_ids,
+	.probe          = soc_sandbox_probe,
+};
diff --git a/test/dm/Makefile b/test/dm/Makefile
index 6c18fd04ce1c..9d570d3f5b89 100644
--- a/test/dm/Makefile
+++ b/test/dm/Makefile
@@ -66,6 +66,7 @@ obj-$(CONFIG_AXI) += axi.o
 obj-$(CONFIG_MISC) += misc.o
 obj-$(CONFIG_DM_SERIAL) += serial.o
 obj-$(CONFIG_CPU) += cpu.o
+obj-$(CONFIG_SOC_DEVICE) += soc.o
 obj-$(CONFIG_SOUND) += sound.o
 obj-$(CONFIG_TEE) += tee.o
 obj-$(CONFIG_VIRTIO_SANDBOX) += virtio.o
diff --git a/test/dm/soc.c b/test/dm/soc.c
new file mode 100644
index 000000000000..17918d7d47b0
--- /dev/null
+++ b/test/dm/soc.c
@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Test for the SOC uclass
+ *
+ * (C) Copyright 2020 - Texas Instruments Incorporated - http://www.ti.com/
+ *	Dave Gerlach <d-gerlach@ti.com>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <dm/test.h>
+#include <dm/uclass-internal.h>
+#include <soc.h>
+#include <test/ut.h>
+
+struct sb_soc_data {
+	unsigned long param;
+};
+
+static int dm_test_soc(struct unit_test_state *uts)
+{
+	struct udevice *dev;
+	char text[128];
+	const struct soc_device_attribute *soc_data;
+	const struct sb_soc_data *match_data;
+
+	static const struct sb_soc_data soc_sandbox1_sr10_data = { 0x91919191 };
+	static const struct sb_soc_data soc_sandbox123_data    = { 0x84848484 };
+
+	static const struct soc_device_attribute sb_soc_devices_full[] = {
+		{
+			.family = "SANDBOX0xx",
+			.machine = "SANDBOX012",
+			.revision = "1.0",
+			.data = NULL,
+		},
+		{
+			.family = "SANDBOX1xx",
+			.machine = "SANDBOX107",
+			.revision = "1.0",
+			.data = NULL,
+		},
+		{
+			.family = "SANDBOX1xx",
+			.machine = "SANDBOX123",
+			.revision = "1.0",
+			.data = &soc_sandbox123_data,
+		},
+		{
+			.family = "SANDBOX1xx",
+			.machine = "SANDBOX131",
+			.revision = "2.0",
+			.data = NULL,
+		},
+		{ /* sentinel */ }
+	};
+
+	static const struct soc_device_attribute sb_soc_devices_partial[] = {
+		{
+			.family = "SANDBOX0xx",
+			.revision = "1.0",
+			.data = NULL,
+		},
+		{
+			.family = "SANDBOX1xx",
+			.revision = "1.0",
+			.data = &soc_sandbox1_sr10_data,
+		},
+		{
+			.family = "SANDBOX1xx",
+			.revision = "2.0",
+			.data = NULL,
+		},
+		{ /* sentinel */ }
+	};
+
+	static const struct soc_device_attribute sb_soc_devices_nomatch[] = {
+		{
+			.family = "SANDBOX0xx",
+			.revision = "1.0",
+			.data = NULL,
+		},
+		{
+			.family = "SANDBOX1xx",
+			.revision = "2.0",
+			.data = NULL,
+		},
+		{ /* sentinel */ }
+	};
+
+	ut_assertok(soc_get(&dev));
+
+	ut_assertok(soc_get_machine(dev, text, sizeof(text)));
+	ut_assertok(strcmp(text, "SANDBOX123"));
+
+	ut_assertok(soc_get_family(dev, text, sizeof(text)));
+	ut_assertok(strcmp(text, "SANDBOX1xx"));
+
+	ut_assertok(soc_get_revision(dev, text, sizeof(text)));
+	ut_asserteq_str(text, "1.0");
+
+	soc_data = soc_device_match(sb_soc_devices_full);
+	ut_assert(soc_data);
+
+	match_data = soc_data->data;
+	ut_asserteq(match_data->param, 0x84848484);
+
+	soc_data = soc_device_match(sb_soc_devices_partial);
+	ut_assert(soc_data);
+
+	match_data = soc_data->data;
+	ut_asserteq(match_data->param, 0x91919191);
+
+	soc_data = soc_device_match(sb_soc_devices_nomatch);
+	ut_asserteq_ptr(soc_data, NULL);
+
+	return 0;
+}
+
+DM_TEST(dm_test_soc, DM_TESTF_SCAN_FDT);
-- 
2.20.1

[PATCH 3/8] dm: soc: Introduce soc_ti_k3 driver for TI K3 SoCs

[Dave Gerlach]

Introduce an soc_ti_k3_driver that allows identification and selection
of SoC specific data based on the JTAG ID register for device
identification, as described for AM65x[0] and J721E[1] devices.

[0] http://www.ti.com/lit/ug/spruid7e/spruid7e.pdf
[1] http://www.ti.com/lit/ug/spruil1a/spruil1a.pdf

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
---
 drivers/soc/Kconfig     |   7 +++
 drivers/soc/Makefile    |   1 +
 drivers/soc/soc_ti_k3.c | 124 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 132 insertions(+)
 create mode 100644 drivers/soc/soc_ti_k3.c

diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index e715dfd01712..864d00a88538 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -9,6 +9,13 @@ config SOC_DEVICE
 	  need different parameters or quirks enabled depending on the
 	  specific device variant in use.
 
+config SOC_DEVICE_TI_K3
+	depends on SOC_DEVICE
+	bool "Enable SoC Device ID driver for TI K3 SoCs"
+	help
+	  This allows Texas Instruments Keystone 3 SoCs to identify
+	  specifics about the SoC in use.
+
 source "drivers/soc/ti/Kconfig"
 
 endmenu
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index 649e92b3906d..9ef20ca5066f 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -4,4 +4,5 @@
 
 obj-$(CONFIG_SOC_TI) += ti/
 obj-$(CONFIG_SOC_DEVICE) += soc-uclass.o
+obj-$(CONFIG_SOC_DEVICE_TI_K3) += soc_ti_k3.o
 obj-$(CONFIG_SANDBOX) += soc_sandbox.o
diff --git a/drivers/soc/soc_ti_k3.c b/drivers/soc/soc_ti_k3.c
new file mode 100644
index 000000000000..ceab58759ca1
--- /dev/null
+++ b/drivers/soc/soc_ti_k3.c
@@ -0,0 +1,124 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com/
+ *	Dave Gerlach <d-gerlach@ti.com>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <soc.h>
+
+#include <asm/io.h>
+
+#define AM65X			0xbb5a
+#define J721E			0xbb64
+
+#define REV_PG1_0		0
+#define REV_PG2_0		1
+
+#define JTAG_ID_VARIANT_SHIFT	28
+#define JTAG_ID_VARIANT_MASK	(0xf << 28)
+#define JTAG_ID_PARTNO_SHIFT	12
+#define JTAG_ID_PARTNO_MASK	(0xffff << 12)
+
+struct soc_ti_k3_platdata {
+	const char *family;
+	const char *revision;
+};
+
+static const char *get_family_string(u32 idreg)
+{
+	const char *family;
+	u32 soc;
+
+	soc = (idreg & JTAG_ID_PARTNO_MASK) >> JTAG_ID_PARTNO_SHIFT;
+
+	switch (soc) {
+	case AM65X:
+		family = "AM65X";
+		break;
+	case J721E:
+		family = "J721E";
+		break;
+	default:
+		family = "Unknown Silicon";
+	};
+
+	return family;
+}
+
+static const char *get_rev_string(u32 idreg)
+{
+	const char *revision;
+	u32 rev;
+
+	rev = (idreg & JTAG_ID_VARIANT_MASK) >> JTAG_ID_VARIANT_SHIFT;
+
+	switch (rev) {
+	case REV_PG1_0:
+		revision = "1.0";
+		break;
+	case REV_PG2_0:
+		revision = "2.0";
+		break;
+	default:
+		revision = "Unknown Revision";
+	};
+
+	return revision;
+}
+
+static int soc_ti_k3_get_family(struct udevice *dev, char *buf, int size)
+{
+	struct soc_ti_k3_platdata *plat = dev_get_platdata(dev);
+
+	snprintf(buf, size, "%s", plat->family);
+
+	return 0;
+}
+
+static int soc_ti_k3_get_revision(struct udevice *dev, char *buf, int size)
+{
+	struct soc_ti_k3_platdata *plat = dev_get_platdata(dev);
+
+	snprintf(buf, size, "SR%s", plat->revision);
+
+	return 0;
+}
+
+static const struct soc_ops soc_ti_k3_ops = {
+	.get_family = soc_ti_k3_get_family,
+	.get_revision = soc_ti_k3_get_revision,
+};
+
+int soc_ti_k3_probe(struct udevice *dev)
+{
+	struct soc_ti_k3_platdata *plat = dev_get_platdata(dev);
+	u32 idreg;
+	void *idreg_addr;
+
+	idreg_addr = dev_read_addr_ptr(dev);
+	if (!idreg_addr)
+		return -EINVAL;
+
+	idreg = readl(idreg_addr);
+
+	plat->family = get_family_string(idreg);
+	plat->revision = get_rev_string(idreg);
+
+	return 0;
+}
+
+static const struct udevice_id soc_ti_k3_ids[] = {
+	{ .compatible = "ti,am654-chipid" },
+	{ }
+};
+
+U_BOOT_DRIVER(soc_ti_k3) = {
+	.name           = "soc_ti_k3",
+	.id             = UCLASS_SOC,
+	.ops		= &soc_ti_k3_ops,
+	.of_match       = soc_ti_k3_ids,
+	.probe          = soc_ti_k3_probe,
+	.platdata_auto_alloc_size = sizeof(struct soc_ti_k3_platdata),
+};
-- 
2.20.1

[PATCH 4/8] arm: dts: k3-am65-wakeup: Introduce chipid node

[Dave Gerlach]

Introduce a chipid node to provide a UCLASS_SOC driver to identify TI K3
SoCs.

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
---
 arch/arm/dts/k3-am65-wakeup.dtsi             | 5 +++++
 arch/arm/dts/k3-am654-base-board-u-boot.dtsi | 4 ++++
 2 files changed, 9 insertions(+)

diff --git a/arch/arm/dts/k3-am65-wakeup.dtsi b/arch/arm/dts/k3-am65-wakeup.dtsi
index 2676d6035b21..666c30d01919 100644
--- a/arch/arm/dts/k3-am65-wakeup.dtsi
+++ b/arch/arm/dts/k3-am65-wakeup.dtsi
@@ -62,4 +62,9 @@
 		clocks = <&k3_clks 115 1>;
 		power-domains = <&k3_pds 115 TI_SCI_PD_EXCLUSIVE>;
 	};
+
+	chipid: chipid at 43000014 {
+		compatible = "ti,am654-chipid";
+		reg = <0x43000014 0x4>;
+	};
 };
diff --git a/arch/arm/dts/k3-am654-base-board-u-boot.dtsi b/arch/arm/dts/k3-am654-base-board-u-boot.dtsi
index a7e5eb055313..ef75a68fd511 100644
--- a/arch/arm/dts/k3-am654-base-board-u-boot.dtsi
+++ b/arch/arm/dts/k3-am654-base-board-u-boot.dtsi
@@ -393,3 +393,7 @@
 		u-boot,dm-spl;
 	};
 };
+
+&chipid {
+	u-boot,dm-spl;
+};
-- 
2.20.1

[PATCH 5/8] arm: dts: k3-j721e-mcu-wakeup: Introduce chipid node

[Dave Gerlach]

Introduce a chipid node to provide a UCLASS_SOC driver to identify TI K3
SoCs.

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
---
 arch/arm/dts/k3-j721e-common-proc-board-u-boot.dtsi | 4 ++++
 arch/arm/dts/k3-j721e-mcu-wakeup.dtsi               | 5 +++++
 2 files changed, 9 insertions(+)

diff --git a/arch/arm/dts/k3-j721e-common-proc-board-u-boot.dtsi b/arch/arm/dts/k3-j721e-common-proc-board-u-boot.dtsi
index 7b01e4204f73..bea77cb1f74c 100644
--- a/arch/arm/dts/k3-j721e-common-proc-board-u-boot.dtsi
+++ b/arch/arm/dts/k3-j721e-common-proc-board-u-boot.dtsi
@@ -377,3 +377,7 @@
 &mcu_fss0_ospi1_pins_default {
 	u-boot,dm-spl;
 };
+
+&chipid {
+	u-boot,dm-spl;
+};
diff --git a/arch/arm/dts/k3-j721e-mcu-wakeup.dtsi b/arch/arm/dts/k3-j721e-mcu-wakeup.dtsi
index 2eed50aa5a4c..7a815620a507 100644
--- a/arch/arm/dts/k3-j721e-mcu-wakeup.dtsi
+++ b/arch/arm/dts/k3-j721e-mcu-wakeup.dtsi
@@ -199,4 +199,9 @@
 		clocks = <&k3_clks 195 0>;
 		power-domains = <&k3_pds 195 TI_SCI_PD_EXCLUSIVE>;
 	};
+
+	chipid: chipid at 43000014 {
+		compatible = "ti,am654-chipid";
+		reg = <0x0 0x43000014 0x0 0x4>;
+	};
 };
-- 
2.20.1

[PATCH 6/8] configs: am65x_evm: Enable CONFIG_SOC_DEVICE and CONFIG_SOC_DEVICE_TI_K3

[Dave Gerlach]

Enable CONFIG_SOC_DEVICE and CONFIG_SOC_DEVICE_TI_K3 so the TI K3 SoC
driver can be used for SoC detection.

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
---
 configs/am65x_evm_a53_defconfig    | 2 ++
 configs/am65x_evm_r5_defconfig     | 2 ++
 configs/am65x_hs_evm_a53_defconfig | 2 ++
 configs/am65x_hs_evm_r5_defconfig  | 2 ++
 4 files changed, 8 insertions(+)

diff --git a/configs/am65x_evm_a53_defconfig b/configs/am65x_evm_a53_defconfig
index d74a2d09309b..32817321e762 100644
--- a/configs/am65x_evm_a53_defconfig
+++ b/configs/am65x_evm_a53_defconfig
@@ -144,3 +144,5 @@ CONFIG_USB_GADGET_PRODUCT_NUM=0x6162
 CONFIG_USB_GADGET_DOWNLOAD=y
 CONFIG_FAT_WRITE=y
 CONFIG_OF_LIBFDT_OVERLAY=y
+CONFIG_SOC_DEVICE=y
+CONFIG_SOC_DEVICE_TI_K3=y
diff --git a/configs/am65x_evm_r5_defconfig b/configs/am65x_evm_r5_defconfig
index 4fc199e80911..f6b1d71d9d83 100644
--- a/configs/am65x_evm_r5_defconfig
+++ b/configs/am65x_evm_r5_defconfig
@@ -118,3 +118,5 @@ CONFIG_TIMER=y
 CONFIG_SPL_TIMER=y
 CONFIG_OMAP_TIMER=y
 CONFIG_FS_FAT_MAX_CLUSTSIZE=16384
+CONFIG_SOC_DEVICE=y
+CONFIG_SOC_DEVICE_TI_K3=y
diff --git a/configs/am65x_hs_evm_a53_defconfig b/configs/am65x_hs_evm_a53_defconfig
index 117953817d82..58f47bd511f3 100644
--- a/configs/am65x_hs_evm_a53_defconfig
+++ b/configs/am65x_hs_evm_a53_defconfig
@@ -146,3 +146,5 @@ CONFIG_USB_GADGET_PRODUCT_NUM=0x6162
 CONFIG_USB_GADGET_DOWNLOAD=y
 CONFIG_FAT_WRITE=y
 CONFIG_OF_LIBFDT_OVERLAY=y
+CONFIG_SOC_DEVICE=y
+CONFIG_SOC_DEVICE_TI_K3=y
diff --git a/configs/am65x_hs_evm_r5_defconfig b/configs/am65x_hs_evm_r5_defconfig
index b2d638672e33..13be670a3647 100644
--- a/configs/am65x_hs_evm_r5_defconfig
+++ b/configs/am65x_hs_evm_r5_defconfig
@@ -119,3 +119,5 @@ CONFIG_TIMER=y
 CONFIG_SPL_TIMER=y
 CONFIG_OMAP_TIMER=y
 CONFIG_FS_FAT_MAX_CLUSTSIZE=16384
+CONFIG_SOC_DEVICE=y
+CONFIG_SOC_DEVICE_TI_K3=y
-- 
2.20.1

[PATCH 7/8] configs: j721e_evm: Enable CONFIG_SOC_DEVICE and CONFIG_SOC_DEVICE_TI_K3

[Dave Gerlach]

Enable CONFIG_SOC_DEVICE and CONFIG_SOC_DEVICE_TI_K3 so the TI K3 SoC
driver can be used for SoC detection.

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
---
 configs/j721e_evm_a72_defconfig    | 2 ++
 configs/j721e_evm_r5_defconfig     | 2 ++
 configs/j721e_hs_evm_a72_defconfig | 2 ++
 configs/j721e_hs_evm_r5_defconfig  | 2 ++
 4 files changed, 8 insertions(+)

diff --git a/configs/j721e_evm_a72_defconfig b/configs/j721e_evm_a72_defconfig
index 4deb4e219fe7..1bc0ef4ed8a0 100644
--- a/configs/j721e_evm_a72_defconfig
+++ b/configs/j721e_evm_a72_defconfig
@@ -168,3 +168,5 @@ CONFIG_CADENCE_UFS=y
 CONFIG_TI_J721E_UFS=y
 CONFIG_FAT_WRITE=y
 CONFIG_OF_LIBFDT_OVERLAY=y
+CONFIG_SOC_DEVICE=y
+CONFIG_SOC_DEVICE_TI_K3=y
diff --git a/configs/j721e_evm_r5_defconfig b/configs/j721e_evm_r5_defconfig
index ee9217aee238..eec5a3c0d11c 100644
--- a/configs/j721e_evm_r5_defconfig
+++ b/configs/j721e_evm_r5_defconfig
@@ -133,3 +133,5 @@ CONFIG_USB_GADGET_PRODUCT_NUM=0x6163
 CONFIG_USB_GADGET_DOWNLOAD=y
 CONFIG_FS_EXT4=y
 CONFIG_FS_FAT_MAX_CLUSTSIZE=16384
+CONFIG_SOC_DEVICE=y
+CONFIG_SOC_DEVICE_TI_K3=y
diff --git a/configs/j721e_hs_evm_a72_defconfig b/configs/j721e_hs_evm_a72_defconfig
index ae540a26a401..c6755e41cc6b 100644
--- a/configs/j721e_hs_evm_a72_defconfig
+++ b/configs/j721e_hs_evm_a72_defconfig
@@ -156,3 +156,5 @@ CONFIG_CADENCE_UFS=y
 CONFIG_TI_J721E_UFS=y
 CONFIG_FAT_WRITE=y
 CONFIG_OF_LIBFDT_OVERLAY=y
+CONFIG_SOC_DEVICE=y
+CONFIG_SOC_DEVICE_TI_K3=y
diff --git a/configs/j721e_hs_evm_r5_defconfig b/configs/j721e_hs_evm_r5_defconfig
index 51d5a3bb98fa..f8893ed58622 100644
--- a/configs/j721e_hs_evm_r5_defconfig
+++ b/configs/j721e_hs_evm_r5_defconfig
@@ -114,3 +114,5 @@ CONFIG_SPL_TIMER=y
 CONFIG_OMAP_TIMER=y
 CONFIG_FS_EXT4=y
 CONFIG_FS_FAT_MAX_CLUSTSIZE=16384
+CONFIG_SOC_DEVICE=y
+CONFIG_SOC_DEVICE_TI_K3=y
-- 
2.20.1

[PATCH 8/8] arm: mach-k3: Use SOC driver for device identification

[Dave Gerlach]

Make use of UCLASS_SOC to find device family and revision for
print_cpuinfo.

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
---
 arch/arm/mach-k3/common.c                | 48 ++++++++++--------------
 arch/arm/mach-k3/include/mach/hardware.h |  1 -
 2 files changed, 19 insertions(+), 30 deletions(-)

diff --git a/arch/arm/mach-k3/common.c b/arch/arm/mach-k3/common.c
index 9695b2236ecd..b88516b8c02b 100644
--- a/arch/arm/mach-k3/common.c
+++ b/arch/arm/mach-k3/common.c
@@ -25,6 +25,7 @@
 #include <fs.h>
 #include <env.h>
 #include <elf.h>
+#include <soc.h>
 
 struct ti_sci_handle *get_ti_sci_handle(void)
 {
@@ -308,38 +309,27 @@ void reset_cpu(ulong ignored)
 #if defined(CONFIG_DISPLAY_CPUINFO)
 int print_cpuinfo(void)
 {
-	u32 soc, rev;
-	char *name;
-
-	soc = (readl(CTRLMMR_WKUP_JTAG_ID) &
-		JTAG_ID_PARTNO_MASK) >> JTAG_ID_PARTNO_SHIFT;
-	rev = (readl(CTRLMMR_WKUP_JTAG_ID) &
-		JTAG_ID_VARIANT_MASK) >> JTAG_ID_VARIANT_SHIFT;
+	struct udevice *soc;
+	char name[64];
+	int ret;
 
 	printf("SoC:   ");
-	switch (soc) {
-	case AM65X:
-		name = "AM65x";
-		break;
-	case J721E:
-		name = "J721E";
-		break;
-	default:
-		name = "Unknown Silicon";
-	};
 
-	printf("%s SR ", name);
-	switch (rev) {
-	case REV_PG1_0:
-		name = "1.0";
-		break;
-	case REV_PG2_0:
-		name = "2.0";
-		break;
-	default:
-		name = "Unknown Revision";
-	};
-	printf("%s\n", name);
+	ret = soc_get(&soc);
+	if (ret) {
+		printf("UNKNOWN\n");
+		return 0;
+	}
+
+	ret = soc_get_family(soc, name, 64);
+	if (!ret) {
+		printf("%s ", name);
+	}
+
+	ret = soc_get_revision(soc, name, 64);
+	if (!ret) {
+		printf("%s\n", name);
+	}
 
 	return 0;
 }
diff --git a/arch/arm/mach-k3/include/mach/hardware.h b/arch/arm/mach-k3/include/mach/hardware.h
index 0ad761418bb7..f2ca80af1a9b 100644
--- a/arch/arm/mach-k3/include/mach/hardware.h
+++ b/arch/arm/mach-k3/include/mach/hardware.h
@@ -15,7 +15,6 @@
 #endif
 
 /* Assuming these addresses and definitions stay common across K3 devices */
-#define CTRLMMR_WKUP_JTAG_ID	0x43000014
 #define JTAG_ID_VARIANT_SHIFT	28
 #define JTAG_ID_VARIANT_MASK	(0xf << 28)
 #define JTAG_ID_PARTNO_SHIFT	12
-- 
2.20.1

[PATCH 1/8] dm: soc: Introduce UCLASS_SOC for SOC ID and attribute matching

[Tom Rini]

On Mon, Jun 29, 2020 at 11:38:46PM -0500, Dave Gerlach wrote:

> Introduce UCLASS_SOC to be used for SOC identification and attribute
> matching based on the SoC ID info. This allows drivers to be provided
> for SoCs to retrieve SoC identifying information and also for matching
> device attributes for selecting SoC specific data.
> 
> This is useful for other device drivers that may need different
> parameters or quirks enabled depending on the specific device variant in
> use.
> 
> Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
> ---
>  drivers/soc/Kconfig      |   9 +++
>  drivers/soc/Makefile     |   1 +
>  drivers/soc/soc-uclass.c | 102 ++++++++++++++++++++++++++++++
>  include/dm/uclass-id.h   |   1 +
>  include/soc.h            | 132 +++++++++++++++++++++++++++++++++++++++
>  5 files changed, 245 insertions(+)
>  create mode 100644 drivers/soc/soc-uclass.c
>  create mode 100644 include/soc.h

Can we please get a write-up in doc/driver-model/ as well for this?
Thanks!

-- 
Tom
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 659 bytes
Desc: not available
URL: <https://lists.denx.de/pipermail/u-boot/attachments/20200630/d03f452e/attachment.sig>

[PATCH 2/8] test: Add tests for SOC uclass

[Simon Glass]

On Mon, 29 Jun 2020 at 22:38, Dave Gerlach <d-gerlach@ti.com> wrote:
>
> Add a sandbox SOC driver, and some tests for the SOC uclass.
>
> Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
> ---
>  arch/sandbox/dts/test.dts          |   4 +
>  configs/sandbox64_defconfig        |   1 +
>  configs/sandbox_defconfig          |   1 +
>  configs/sandbox_flattree_defconfig |   1 +
>  configs/sandbox_spl_defconfig      |   1 +
>  drivers/soc/Makefile               |   1 +
>  drivers/soc/soc_sandbox.c          |  56 ++++++++++++++
>  test/dm/Makefile                   |   1 +
>  test/dm/soc.c                      | 120 +++++++++++++++++++++++++++++
>  9 files changed, 186 insertions(+)
>  create mode 100644 drivers/soc/soc_sandbox.c
>  create mode 100644 test/dm/soc.c
>

Reviewed-by: Simon Glass <sjg@chromium.org>

[PATCH 1/8] dm: soc: Introduce UCLASS_SOC for SOC ID and attribute matching

[Simon Glass]

On Mon, 29 Jun 2020 at 22:38, Dave Gerlach <d-gerlach@ti.com> wrote:
>
> Introduce UCLASS_SOC to be used for SOC identification and attribute
> matching based on the SoC ID info. This allows drivers to be provided
> for SoCs to retrieve SoC identifying information and also for matching
> device attributes for selecting SoC specific data.
>
> This is useful for other device drivers that may need different
> parameters or quirks enabled depending on the specific device variant in
> use.
>
> Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
> ---
>  drivers/soc/Kconfig      |   9 +++
>  drivers/soc/Makefile     |   1 +
>  drivers/soc/soc-uclass.c | 102 ++++++++++++++++++++++++++++++
>  include/dm/uclass-id.h   |   1 +
>  include/soc.h            | 132 +++++++++++++++++++++++++++++++++++++++
>  5 files changed, 245 insertions(+)
>  create mode 100644 drivers/soc/soc-uclass.c
>  create mode 100644 include/soc.h

Reviewed-by: Simon Glass <sjg@chromium.org>

As Tom says, docs please but looks great otherwise.

Nits below. Do you think it might make sense to have an
integer-encoded version? Maybe it would be more hassle than it is
worth.

>
> diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
> index 7b4e4d613088..e715dfd01712 100644
> --- a/drivers/soc/Kconfig
> +++ b/drivers/soc/Kconfig
> @@ -1,5 +1,14 @@
>  menu "SOC (System On Chip) specific Drivers"
>
> +config SOC_DEVICE
> +       bool "Enable SoC Device ID drivers using Driver Model"
> +       help
> +         This allows drivers to be provided for SoCs to help in identifying
> +         the SoC in use and matching SoC attributes for selecting SoC
> +         specific data. This is useful for other device drivers that may
> +         need different parameters or quirks enabled depending on the
> +         specific device variant in use.
> +
>  source "drivers/soc/ti/Kconfig"
>
>  endmenu
> diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
> index ce253b7aa886..1c09a8465670 100644
> --- a/drivers/soc/Makefile
> +++ b/drivers/soc/Makefile
> @@ -3,3 +3,4 @@
>  # Makefile for the U-Boot SOC specific device drivers.
>
>  obj-$(CONFIG_SOC_TI) += ti/
> +obj-$(CONFIG_SOC_DEVICE) += soc-uclass.o
> diff --git a/drivers/soc/soc-uclass.c b/drivers/soc/soc-uclass.c
> new file mode 100644
> index 000000000000..22f89514ed7d
> --- /dev/null
> +++ b/drivers/soc/soc-uclass.c
> @@ -0,0 +1,102 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * (C) Copyright 2020 - Texas Instruments Incorporated - http://www.ti.com/
> + *     Dave Gerlach <d-gerlach@ti.com>
> + */
> +
> +#include <common.h>
> +#include <soc.h>
> +#include <dm.h>
> +#include <errno.h>
> +#include <dm/lists.h>
> +#include <dm/root.h>
> +
> +int soc_get(struct udevice **devp)
> +{
> +       return uclass_first_device_err(UCLASS_SOC, devp);
> +}
> +
> +int soc_get_machine(struct udevice *dev, char *buf, int size)
> +{
> +       struct soc_ops *ops = soc_get_ops(dev);
> +
> +       if (!ops->get_machine)
> +               return -ENOSYS;
> +
> +       return ops->get_machine(dev, buf, size);
> +}
> +
> +int soc_get_family(struct udevice *dev, char *buf, int size)
> +{
> +       struct soc_ops *ops = soc_get_ops(dev);
> +
> +       if (!ops->get_family)
> +               return -ENOSYS;
> +
> +       return ops->get_family(dev, buf, size);
> +}
> +
> +int soc_get_revision(struct udevice *dev, char *buf, int size)
> +{
> +       struct soc_ops *ops = soc_get_ops(dev);
> +
> +       if (!ops->get_revision)
> +               return -ENOSYS;
> +
> +       return ops->get_revision(dev, buf, size);
> +}
> +
> +const struct soc_device_attribute *
> +soc_device_match(const struct soc_device_attribute *matches)
> +{
> +       bool match;
> +       struct udevice *soc;
> +       char str[SOC_MAX_STR_SIZE];
> +
> +       if (!matches)
> +               return NULL;
> +
> +       if (soc_get(&soc))
> +               return NULL;
> +
> +       while (1) {
> +               if (!(matches->machine || matches->family ||
> +                     matches->revision))
> +                       break;
> +
> +               match = true;
> +
> +               if (matches->machine) {
> +                       if (!soc_get_machine(soc, str, SOC_MAX_STR_SIZE)) {
> +                               if (strcmp(matches->machine, str))
> +                                       match = false;
> +                       }
> +               }
> +
> +               if (matches->family) {
> +                       if (!soc_get_family(soc, str, SOC_MAX_STR_SIZE)) {
> +                               if (strcmp(matches->family, str))
> +                                       match = false;
> +                       }
> +               }
> +
> +               if (matches->revision) {
> +                       if (!soc_get_revision(soc, str, SOC_MAX_STR_SIZE)) {
> +                               if (strcmp(matches->revision, str))
> +                                       match = false;
> +                       }
> +               }
> +
> +               if (match)
> +                       return matches;
> +
> +               matches++;
> +       }
> +
> +       return NULL;
> +}
> +
> +UCLASS_DRIVER(soc) = {
> +       .id             = UCLASS_SOC,
> +       .name           = "soc",
> +};
> diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
> index 7837d459f18c..690a8ed4df49 100644
> --- a/include/dm/uclass-id.h
> +++ b/include/dm/uclass-id.h
> @@ -97,6 +97,7 @@ enum uclass_id {
>         UCLASS_SERIAL,          /* Serial UART */
>         UCLASS_SIMPLE_BUS,      /* Bus with child devices */
>         UCLASS_SMEM,            /* Shared memory interface */
> +       UCLASS_SOC,             /* SOC Device */
>         UCLASS_SOUND,           /* Playing simple sounds */
>         UCLASS_SPI,             /* SPI bus */
>         UCLASS_SPI_FLASH,       /* SPI flash */
> diff --git a/include/soc.h b/include/soc.h
> new file mode 100644
> index 000000000000..98e3cc000198
> --- /dev/null
> +++ b/include/soc.h
> @@ -0,0 +1,132 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +/*
> + * (C) Copyright 2020 - Texas Instruments Incorporated - http://www.ti.com/
> + *     Dave Gerlach <d-gerlach@ti.com>
> + */
> +
> +#ifndef __SOC_H
> +#define __SOC_H
> +
> +#define SOC_MAX_STR_SIZE       128
> +
> +struct soc_device_attribute {

Could this be soc_attr or maybe soc_dev_attr? This is too long.

> +       const char *machine;
> +       const char *family;
> +       const char *revision;
> +       const void *data;

Please can you comment this struct with what each thing means and an
example for your SoC.

> +};
> +
> +#ifdef CONFIG_SOC_DEVICE

Please drop the #ifdef as there is no harm in defining this.

> +struct soc_ops {
> +       /**
> +        * get_machine() - Get machine name of an SOC
> +        *
> +        * @dev:        Device to check (UCLASS_SOC)
> +        * @buf:        Buffer to place string
> +        * @size:       Size of string space
> +        * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
> +        */
> +       int (*get_machine)(struct udevice *dev, char *buf, int size);
> +
> +       /**
> +        * get_revision() - Get revision name of a SOC
> +        *
> +        * @dev:        Device to check (UCLASS_SOC)
> +        * @buf:        Buffer to place string
> +        * @size:       Size of string space
> +        * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
> +        */
> +       int (*get_revision)(struct udevice *dev, char *buf, int size);
> +
> +       /**
> +        * get_family() - Get family name of an SOC
> +        *
> +        * @dev:        Device to check (UCLASS_SOC)
> +        * @buf:        Buffer to place string
> +        * @size:       Size of string space
> +        * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
> +        */
> +       int (*get_family)(struct udevice *dev, char *buf, int size);
> +};
> +
> +#define soc_get_ops(dev)        ((struct soc_ops *)(dev)->driver->ops)
> +
> +/**
> + * soc_get() - Return the soc device for the soc in use.
> + * @devp: Pointer to structure to receive the soc device.
> + *
> + * Since there can only be at most one SOC instance, the API can supply a
> + * function that returns the unique device.
> + *
> + * Return: 0 if OK, -ve on error.
> + */
> +int soc_get(struct udevice **devp);
> +
> +/**
> + * soc_get_machine() - Get machine name of an SOC
> + * @dev:       Device to check (UCLASS_SOC)
> + * @buf:       Buffer to place string
> + * @size:      Size of string space
> + *
> + * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
> + */
> +int soc_get_machine(struct udevice *dev, char *buf, int size);
> +
> +/**
> + * soc_get_revision() - Get revision name of an SOC
> + * @dev:       Device to check (UCLASS_SOC)
> + * @buf:       Buffer to place string
> + * @size:      Size of string space
> + *
> + * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
> + */
> +int soc_get_revision(struct udevice *dev, char *buf, int size);
> +
> +/**
> + * soc_get_family() - Get family name of an SOC
> + * @dev:       Device to check (UCLASS_SOC)
> + * @buf:       Buffer to place string
> + * @size:      Size of string space
> + *
> + * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
> + */
> +int soc_get_family(struct udevice *dev, char *buf, int size);
> +
> +/**
> + * soc_device_match() - Return match from an array of soc_device_attribute
> + * @matches:   Array with any combination of family, revision or machine set
> + *
> + * Return: Pointer to struct from matches array with set attributes matching
> + *        those provided by the soc device.

or NULL ?

> + */
> +const struct soc_device_attribute *
> +soc_device_match(const struct soc_device_attribute *matches);
> +
> +#else
> +static inline int soc_get(struct udevice **devp)
> +{
> +       return -ENOSYS;
> +}
> +
> +static inline int soc_get_machine(struct udevice *dev, char *buf, int size)
> +{
> +       return -ENOSYS;
> +}
> +
> +static inline int soc_get_revision(struct udevice *dev, char *buf, int size)
> +{
> +       return -ENOSYS;
> +}
> +
> +static inline int soc_get_family(struct udevice *dev, char *buf, int size)
> +{
> +       return -ENOSYS;
> +}
> +
> +static inline const struct soc_device_attribute *
> +soc_device_match(const struct soc_device_attribute *matches)
> +{
> +       return NULL;
> +}
> +#endif
> +#endif /* _SOC_H */
> --
> 2.20.1
>

Regards,
Simon

[PATCH 0/8] Introduce UCLASS_SOC

[Lokesh Vutla]

Hi Dave,

On 30/06/20 10:08 am, Dave Gerlach wrote:
> Hi,
> 
> This patch series introduces UCLASS_SOC to be used for SOC identification and
> attribute matching based on SoC ID info. This allows drivers to be
> provided for SoCs to retrieve SoC identifying information and also for matching
> device attributes for selecting SoC specific data. This is intended to be a
> counterpart to the soc-device framework in the Linux kernel.
> 
> I started with attempts to extend either UCLASS_CPU and UCLASS_BOARD to provide
> equivalent functionality, but UCLASS_CPU is focused specifically on processing
> units, of which multiples can exist heterogeneously in a system, and
> UCLASS_BOARD is focused on indentifying things connected to an SoC dynamically.
> Rather than try to force this into the existing UCLASS's, a new UCLASS seemed
> appropriate to provide same services as the soc-device functionality
> in the kernel.
> 
> This is useful for other device drivers that may need different
> parameters or quirks enabled depending on the specific device variant or
> revision in use.
> 
> Additionally, this introduces a user of UCLASS_SOC, soc_ti_k3, which provides
> SoC identifying information for K3 SoCs which can be used directly, for
> print_cpuinfo, and for selecting SoC specific data using soc_device_match.

Series looks good to me. Can you please re post the series addressing comments
from Tom and Simon?

Thanks and regards,
Lokesh

> 
> Regards,
> Dave
> 
> Dave Gerlach (8):
>   dm: soc: Introduce UCLASS_SOC for SOC ID and attribute matching
>   test: Add tests for SOC uclass
>   dm: soc: Introduce soc_ti_k3 driver for TI K3 SoCs
>   arm: dts: k3-am65-wakeup: Introduce chipid node
>   arm: dts: k3-j721e-mcu-wakeup: Introduce chipid node
>   configs: am65x_evm: Enable CONFIG_SOC_DEVICE and
>     CONFIG_SOC_DEVICE_TI_K3
>   configs: j721e_evm: Enable CONFIG_SOC_DEVICE and
>     CONFIG_SOC_DEVICE_TI_K3
>   arm: mach-k3: Use SOC driver for device identification
> 
>  arch/arm/dts/k3-am65-wakeup.dtsi              |   5 +
>  arch/arm/dts/k3-am654-base-board-u-boot.dtsi  |   4 +
>  .../k3-j721e-common-proc-board-u-boot.dtsi    |   4 +
>  arch/arm/dts/k3-j721e-mcu-wakeup.dtsi         |   5 +
>  arch/arm/mach-k3/common.c                     |  48 +++----
>  arch/arm/mach-k3/include/mach/hardware.h      |   1 -
>  arch/sandbox/dts/test.dts                     |   4 +
>  configs/am65x_evm_a53_defconfig               |   2 +
>  configs/am65x_evm_r5_defconfig                |   2 +
>  configs/am65x_hs_evm_a53_defconfig            |   2 +
>  configs/am65x_hs_evm_r5_defconfig             |   2 +
>  configs/j721e_evm_a72_defconfig               |   2 +
>  configs/j721e_evm_r5_defconfig                |   2 +
>  configs/j721e_hs_evm_a72_defconfig            |   2 +
>  configs/j721e_hs_evm_r5_defconfig             |   2 +
>  configs/sandbox64_defconfig                   |   1 +
>  configs/sandbox_defconfig                     |   1 +
>  configs/sandbox_flattree_defconfig            |   1 +
>  configs/sandbox_spl_defconfig                 |   1 +
>  drivers/soc/Kconfig                           |  16 +++
>  drivers/soc/Makefile                          |   3 +
>  drivers/soc/soc-uclass.c                      | 102 ++++++++++++++
>  drivers/soc/soc_sandbox.c                     |  56 ++++++++
>  drivers/soc/soc_ti_k3.c                       | 124 ++++++++++++++++
>  include/dm/uclass-id.h                        |   1 +
>  include/soc.h                                 | 132 ++++++++++++++++++
>  test/dm/Makefile                              |   1 +
>  test/dm/soc.c                                 | 120 ++++++++++++++++
>  28 files changed, 616 insertions(+), 30 deletions(-)
>  create mode 100644 drivers/soc/soc-uclass.c
>  create mode 100644 drivers/soc/soc_sandbox.c
>  create mode 100644 drivers/soc/soc_ti_k3.c
>  create mode 100644 include/soc.h
>  create mode 100644 test/dm/soc.c
> 

[PATCH 1/8] dm: soc: Introduce UCLASS_SOC for SOC ID and attribute matching

[Dave Gerlach]

Tom,
On 6/30/20 7:43 AM, Tom Rini wrote:
> On Mon, Jun 29, 2020 at 11:38:46PM -0500, Dave Gerlach wrote:
> 
>> Introduce UCLASS_SOC to be used for SOC identification and attribute
>> matching based on the SoC ID info. This allows drivers to be provided
>> for SoCs to retrieve SoC identifying information and also for matching
>> device attributes for selecting SoC specific data.
>>
>> This is useful for other device drivers that may need different
>> parameters or quirks enabled depending on the specific device variant in
>> use.
>>
>> Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
>> ---
>>   drivers/soc/Kconfig      |   9 +++
>>   drivers/soc/Makefile     |   1 +
>>   drivers/soc/soc-uclass.c | 102 ++++++++++++++++++++++++++++++
>>   include/dm/uclass-id.h   |   1 +
>>   include/soc.h            | 132 +++++++++++++++++++++++++++++++++++++++
>>   5 files changed, 245 insertions(+)
>>   create mode 100644 drivers/soc/soc-uclass.c
>>   create mode 100644 include/soc.h
> 
> Can we please get a write-up in doc/driver-model/ as well for this?
> Thanks!
> 

Yes, will add for v2, thanks for the suggestion.

Regards,
Dave

[PATCH 1/8] dm: soc: Introduce UCLASS_SOC for SOC ID and attribute matching

[Dave Gerlach]

Simon,
On 7/2/20 10:50 PM, Simon Glass wrote:
> On Mon, 29 Jun 2020 at 22:38, Dave Gerlach <d-gerlach@ti.com> wrote:
>>
>> Introduce UCLASS_SOC to be used for SOC identification and attribute
>> matching based on the SoC ID info. This allows drivers to be provided
>> for SoCs to retrieve SoC identifying information and also for matching
>> device attributes for selecting SoC specific data.
>>
>> This is useful for other device drivers that may need different
>> parameters or quirks enabled depending on the specific device variant in
>> use.
>>
>> Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
>> ---
>>   drivers/soc/Kconfig      |   9 +++
>>   drivers/soc/Makefile     |   1 +
>>   drivers/soc/soc-uclass.c | 102 ++++++++++++++++++++++++++++++
>>   include/dm/uclass-id.h   |   1 +
>>   include/soc.h            | 132 +++++++++++++++++++++++++++++++++++++++
>>   5 files changed, 245 insertions(+)
>>   create mode 100644 drivers/soc/soc-uclass.c
>>   create mode 100644 include/soc.h
> 
> Reviewed-by: Simon Glass <sjg@chromium.org>
> 
> As Tom says, docs please but looks great otherwise.
> 

Yes will add docs in v2.

> Nits below. Do you think it might make sense to have an
> integer-encoded version? Maybe it would be more hassle than it is
> worth.

Well my primary driver for using strings was to be consistent with the 
kernel counterpart, but I also thought it was convenient beacuse it 
allows the identifiers to be descriptive and also to be printed out 
directly once retrieved. Attributes could be added as needed in the future.

> 
>>
>> diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
>> index 7b4e4d613088..e715dfd01712 100644
>> --- a/drivers/soc/Kconfig
>> +++ b/drivers/soc/Kconfig
>> @@ -1,5 +1,14 @@
>>   menu "SOC (System On Chip) specific Drivers"
>>
>> +config SOC_DEVICE
>> +       bool "Enable SoC Device ID drivers using Driver Model"
>> +       help
>> +         This allows drivers to be provided for SoCs to help in identifying
>> +         the SoC in use and matching SoC attributes for selecting SoC
>> +         specific data. This is useful for other device drivers that may
>> +         need different parameters or quirks enabled depending on the
>> +         specific device variant in use.
>> +
>>   source "drivers/soc/ti/Kconfig"
>>
>>   endmenu
>> diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
>> index ce253b7aa886..1c09a8465670 100644
>> --- a/drivers/soc/Makefile
>> +++ b/drivers/soc/Makefile
>> @@ -3,3 +3,4 @@
>>   # Makefile for the U-Boot SOC specific device drivers.
>>
>>   obj-$(CONFIG_SOC_TI) += ti/
>> +obj-$(CONFIG_SOC_DEVICE) += soc-uclass.o
>> diff --git a/drivers/soc/soc-uclass.c b/drivers/soc/soc-uclass.c
>> new file mode 100644
>> index 000000000000..22f89514ed7d
>> --- /dev/null
>> +++ b/drivers/soc/soc-uclass.c
>> @@ -0,0 +1,102 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +/*
>> + * (C) Copyright 2020 - Texas Instruments Incorporated - http://www.ti.com/
>> + *     Dave Gerlach <d-gerlach@ti.com>
>> + */
>> +
>> +#include <common.h>
>> +#include <soc.h>
>> +#include <dm.h>
>> +#include <errno.h>
>> +#include <dm/lists.h>
>> +#include <dm/root.h>
>> +
>> +int soc_get(struct udevice **devp)
>> +{
>> +       return uclass_first_device_err(UCLASS_SOC, devp);
>> +}
>> +
>> +int soc_get_machine(struct udevice *dev, char *buf, int size)
>> +{
>> +       struct soc_ops *ops = soc_get_ops(dev);
>> +
>> +       if (!ops->get_machine)
>> +               return -ENOSYS;
>> +
>> +       return ops->get_machine(dev, buf, size);
>> +}
>> +
>> +int soc_get_family(struct udevice *dev, char *buf, int size)
>> +{
>> +       struct soc_ops *ops = soc_get_ops(dev);
>> +
>> +       if (!ops->get_family)
>> +               return -ENOSYS;
>> +
>> +       return ops->get_family(dev, buf, size);
>> +}
>> +
>> +int soc_get_revision(struct udevice *dev, char *buf, int size)
>> +{
>> +       struct soc_ops *ops = soc_get_ops(dev);
>> +
>> +       if (!ops->get_revision)
>> +               return -ENOSYS;
>> +
>> +       return ops->get_revision(dev, buf, size);
>> +}
>> +
>> +const struct soc_device_attribute *
>> +soc_device_match(const struct soc_device_attribute *matches)
>> +{
>> +       bool match;
>> +       struct udevice *soc;
>> +       char str[SOC_MAX_STR_SIZE];
>> +
>> +       if (!matches)
>> +               return NULL;
>> +
>> +       if (soc_get(&soc))
>> +               return NULL;
>> +
>> +       while (1) {
>> +               if (!(matches->machine || matches->family ||
>> +                     matches->revision))
>> +                       break;
>> +
>> +               match = true;
>> +
>> +               if (matches->machine) {
>> +                       if (!soc_get_machine(soc, str, SOC_MAX_STR_SIZE)) {
>> +                               if (strcmp(matches->machine, str))
>> +                                       match = false;
>> +                       }
>> +               }
>> +
>> +               if (matches->family) {
>> +                       if (!soc_get_family(soc, str, SOC_MAX_STR_SIZE)) {
>> +                               if (strcmp(matches->family, str))
>> +                                       match = false;
>> +                       }
>> +               }
>> +
>> +               if (matches->revision) {
>> +                       if (!soc_get_revision(soc, str, SOC_MAX_STR_SIZE)) {
>> +                               if (strcmp(matches->revision, str))
>> +                                       match = false;
>> +                       }
>> +               }
>> +
>> +               if (match)
>> +                       return matches;
>> +
>> +               matches++;
>> +       }
>> +
>> +       return NULL;
>> +}
>> +
>> +UCLASS_DRIVER(soc) = {
>> +       .id             = UCLASS_SOC,
>> +       .name           = "soc",
>> +};
>> diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
>> index 7837d459f18c..690a8ed4df49 100644
>> --- a/include/dm/uclass-id.h
>> +++ b/include/dm/uclass-id.h
>> @@ -97,6 +97,7 @@ enum uclass_id {
>>          UCLASS_SERIAL,          /* Serial UART */
>>          UCLASS_SIMPLE_BUS,      /* Bus with child devices */
>>          UCLASS_SMEM,            /* Shared memory interface */
>> +       UCLASS_SOC,             /* SOC Device */
>>          UCLASS_SOUND,           /* Playing simple sounds */
>>          UCLASS_SPI,             /* SPI bus */
>>          UCLASS_SPI_FLASH,       /* SPI flash */
>> diff --git a/include/soc.h b/include/soc.h
>> new file mode 100644
>> index 000000000000..98e3cc000198
>> --- /dev/null
>> +++ b/include/soc.h
>> @@ -0,0 +1,132 @@
>> +/* SPDX-License-Identifier: GPL-2.0+ */
>> +/*
>> + * (C) Copyright 2020 - Texas Instruments Incorporated - http://www.ti.com/
>> + *     Dave Gerlach <d-gerlach@ti.com>
>> + */
>> +
>> +#ifndef __SOC_H
>> +#define __SOC_H
>> +
>> +#define SOC_MAX_STR_SIZE       128
>> +
>> +struct soc_device_attribute {
> 
> Could this be soc_attr or maybe soc_dev_attr? This is too long.

Good idea, it is too long for no reason, I will shorten it.

> 
>> +       const char *machine;
>> +       const char *family;
>> +       const char *revision;
>> +       const void *data;
> 
> Please can you comment this struct with what each thing means and an
> example for your SoC.

Will do.

> 
>> +};
>> +
>> +#ifdef CONFIG_SOC_DEVICE
> 
> Please drop the #ifdef as there is no harm in defining this.

Ok, will move it lower to wrap the functions so that stubs are still 
defined when !CONFIG_SOC_DEVICE.

> 
>> +struct soc_ops {
>> +       /**
>> +        * get_machine() - Get machine name of an SOC
>> +        *
>> +        * @dev:        Device to check (UCLASS_SOC)
>> +        * @buf:        Buffer to place string
>> +        * @size:       Size of string space
>> +        * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
>> +        */
>> +       int (*get_machine)(struct udevice *dev, char *buf, int size);
>> +
>> +       /**
>> +        * get_revision() - Get revision name of a SOC
>> +        *
>> +        * @dev:        Device to check (UCLASS_SOC)
>> +        * @buf:        Buffer to place string
>> +        * @size:       Size of string space
>> +        * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
>> +        */
>> +       int (*get_revision)(struct udevice *dev, char *buf, int size);
>> +
>> +       /**
>> +        * get_family() - Get family name of an SOC
>> +        *
>> +        * @dev:        Device to check (UCLASS_SOC)
>> +        * @buf:        Buffer to place string
>> +        * @size:       Size of string space
>> +        * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
>> +        */
>> +       int (*get_family)(struct udevice *dev, char *buf, int size);
>> +};
>> +
>> +#define soc_get_ops(dev)        ((struct soc_ops *)(dev)->driver->ops)
>> +
>> +/**
>> + * soc_get() - Return the soc device for the soc in use.
>> + * @devp: Pointer to structure to receive the soc device.
>> + *
>> + * Since there can only be at most one SOC instance, the API can supply a
>> + * function that returns the unique device.
>> + *
>> + * Return: 0 if OK, -ve on error.
>> + */
>> +int soc_get(struct udevice **devp);
>> +
>> +/**
>> + * soc_get_machine() - Get machine name of an SOC
>> + * @dev:       Device to check (UCLASS_SOC)
>> + * @buf:       Buffer to place string
>> + * @size:      Size of string space
>> + *
>> + * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
>> + */
>> +int soc_get_machine(struct udevice *dev, char *buf, int size);
>> +
>> +/**
>> + * soc_get_revision() - Get revision name of an SOC
>> + * @dev:       Device to check (UCLASS_SOC)
>> + * @buf:       Buffer to place string
>> + * @size:      Size of string space
>> + *
>> + * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
>> + */
>> +int soc_get_revision(struct udevice *dev, char *buf, int size);
>> +
>> +/**
>> + * soc_get_family() - Get family name of an SOC
>> + * @dev:       Device to check (UCLASS_SOC)
>> + * @buf:       Buffer to place string
>> + * @size:      Size of string space
>> + *
>> + * Return: 0 if OK, -ENOSPC if buffer is too small, other -ve on error
>> + */
>> +int soc_get_family(struct udevice *dev, char *buf, int size);
>> +
>> +/**
>> + * soc_device_match() - Return match from an array of soc_device_attribute
>> + * @matches:   Array with any combination of family, revision or machine set
>> + *
>> + * Return: Pointer to struct from matches array with set attributes matching
>> + *        those provided by the soc device.
> 
> or NULL ?

Yes, must document the not found case as well. Will add. Appreciate the 
comments!

Regards,
Dave

> 
>> + */
>> +const struct soc_device_attribute *
>> +soc_device_match(const struct soc_device_attribute *matches);
>> +
>> +#else
>> +static inline int soc_get(struct udevice **devp)
>> +{
>> +       return -ENOSYS;
>> +}
>> +
>> +static inline int soc_get_machine(struct udevice *dev, char *buf, int size)
>> +{
>> +       return -ENOSYS;
>> +}
>> +
>> +static inline int soc_get_revision(struct udevice *dev, char *buf, int size)
>> +{
>> +       return -ENOSYS;
>> +}
>> +
>> +static inline int soc_get_family(struct udevice *dev, char *buf, int size)
>> +{
>> +       return -ENOSYS;
>> +}
>> +
>> +static inline const struct soc_device_attribute *
>> +soc_device_match(const struct soc_device_attribute *matches)
>> +{
>> +       return NULL;
>> +}
>> +#endif
>> +#endif /* _SOC_H */
>> --
>> 2.20.1
>>
> 
> Regards,
> Simon
>