[PATCH v5 1/2] soc: samsung: add exynos chipid driver support

[pankaj.dubey@samsung.com (Pankaj Dubey)]

Exynos SoCs have Chipid, for identification of product IDs
and SoC revisions. This patch intendes to provide initialization
code for all these functionalites.

This driver usese existing binding for exnos-chipid.

CC: Grant Likely <grant.likely@linaro.org>
CC: Rob Herring <robh+dt@kernel.org>
CC: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com>
---
 drivers/soc/Kconfig                    |   1 +
 drivers/soc/Makefile                   |   1 +
 drivers/soc/samsung/Kconfig            |  14 +++
 drivers/soc/samsung/Makefile           |   1 +
 drivers/soc/samsung/exynos-chipid.c    | 168 +++++++++++++++++++++++++++++++++
 include/linux/soc/samsung/exynos-soc.h |  51 ++++++++++
 6 files changed, 236 insertions(+)
 create mode 100644 drivers/soc/samsung/Kconfig
 create mode 100644 drivers/soc/samsung/Makefile
 create mode 100644 drivers/soc/samsung/exynos-chipid.c
 create mode 100644 include/linux/soc/samsung/exynos-soc.h

diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index 76d6bd4..c3abfbe 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -1,6 +1,7 @@
 menu "SOC (System On Chip) specific Drivers"
 
 source "drivers/soc/qcom/Kconfig"
+source "drivers/soc/samsung/Kconfig"
 source "drivers/soc/ti/Kconfig"
 source "drivers/soc/versatile/Kconfig"
 
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index 063113d..620366f 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -3,6 +3,7 @@
 #
 
 obj-$(CONFIG_ARCH_QCOM)		+= qcom/
+obj-$(CONFIG_SOC_SAMSUNG)	+= samsung/
 obj-$(CONFIG_ARCH_TEGRA)	+= tegra/
 obj-$(CONFIG_SOC_TI)		+= ti/
 obj-$(CONFIG_PLAT_VERSATILE)	+= versatile/
diff --git a/drivers/soc/samsung/Kconfig b/drivers/soc/samsung/Kconfig
new file mode 100644
index 0000000..2d83652
--- /dev/null
+++ b/drivers/soc/samsung/Kconfig
@@ -0,0 +1,14 @@
+#
+# SAMSUNG SoC drivers
+#
+menu "Samsung SOC driver support"
+
+config SOC_SAMSUNG
+	bool
+
+config EXYNOS_CHIPID
+	bool
+	depends on ARCH_EXYNOS
+	select SOC_BUS
+
+endmenu
diff --git a/drivers/soc/samsung/Makefile b/drivers/soc/samsung/Makefile
new file mode 100644
index 0000000..855ca05
--- /dev/null
+++ b/drivers/soc/samsung/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_EXYNOS_CHIPID)	+= exynos-chipid.o
diff --git a/drivers/soc/samsung/exynos-chipid.c b/drivers/soc/samsung/exynos-chipid.c
new file mode 100644
index 0000000..8968f83
--- /dev/null
+++ b/drivers/soc/samsung/exynos-chipid.c
@@ -0,0 +1,168 @@
+/*
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd.
+ *	      http://www.samsung.com/
+ *
+ * EXYNOS - CHIP ID support
+ * Author: Pankaj Dubey <pankaj.dubey@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/sys_soc.h>
+#include <linux/soc/samsung/exynos-soc.h>
+
+#define EXYNOS_SUBREV_MASK	(0xF << 4)
+#define EXYNOS_MAINREV_MASK	(0xF << 0)
+#define EXYNOS_REV_MASK		(EXYNOS_SUBREV_MASK | EXYNOS_MAINREV_MASK)
+
+static void __iomem *exynos_chipid_base;
+
+struct exynos_chipid_info exynos_soc_info;
+EXPORT_SYMBOL(exynos_soc_info);
+
+static const char * __init product_id_to_name(unsigned int product_id)
+{
+	const char *soc_name;
+	unsigned int soc_id = product_id & EXYNOS_SOC_MASK;
+
+	switch (soc_id) {
+	case EXYNOS3250_SOC_ID:
+		soc_name = "EXYNOS3250";
+		break;
+	case EXYNOS4210_SOC_ID:
+		soc_name = "EXYNOS4210";
+		break;
+	case EXYNOS4212_SOC_ID:
+		soc_name = "EXYNOS4212";
+		break;
+	case EXYNOS4412_SOC_ID:
+		soc_name = "EXYNOS4412";
+		break;
+	case EXYNOS4415_SOC_ID:
+		soc_name = "EXYNOS4415";
+		break;
+	case EXYNOS5250_SOC_ID:
+		soc_name = "EXYNOS5250";
+		break;
+	case EXYNOS5260_SOC_ID:
+		soc_name = "EXYNOS5260";
+		break;
+	case EXYNOS5420_SOC_ID:
+		soc_name = "EXYNOS5420";
+		break;
+	case EXYNOS5440_SOC_ID:
+		soc_name = "EXYNOS5440";
+		break;
+	case EXYNOS5800_SOC_ID:
+		soc_name = "EXYNOS5800";
+		break;
+	default:
+		soc_name = "UNKNOWN";
+	}
+	return soc_name;
+}
+
+static const struct of_device_id of_exynos_chipid_ids[] __initconst = {
+	{
+		.compatible	= "samsung,exynos4210-chipid",
+	},
+	{},
+};
+
+/**
+ *  exynos_chipid_early_init: Early chipid initialization
+ *  @dev: pointer to chipid device
+ */
+void __init exynos_chipid_early_init(struct device *dev)
+{
+	struct device_node *np;
+	const struct of_device_id *match;
+
+	if (exynos_chipid_base)
+		return;
+
+	if (!dev)
+		np = of_find_matching_node_and_match(NULL,
+			of_exynos_chipid_ids, &match);
+	else
+		np = dev->of_node;
+
+	if (!np)
+		panic("%s, failed to find chipid node\n", __func__);
+
+	exynos_chipid_base = of_iomap(np, 0);
+
+	if (!exynos_chipid_base)
+		panic("%s: failed to map registers\n", __func__);
+
+	exynos_soc_info.product_id  = __raw_readl(exynos_chipid_base);
+	exynos_soc_info.revision = exynos_soc_info.product_id & EXYNOS_REV_MASK;
+}
+
+static int __init exynos_chipid_probe(struct platform_device *pdev)
+{
+	struct soc_device_attribute *soc_dev_attr;
+	struct soc_device *soc_dev;
+	struct device_node *root;
+	int ret;
+
+	exynos_chipid_early_init(&pdev->dev);
+
+	soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
+	if (!soc_dev_attr)
+		return -ENODEV;
+
+	soc_dev_attr->family = "Samsung Exynos";
+
+	root = of_find_node_by_path("/");
+	ret = of_property_read_string(root, "model", &soc_dev_attr->machine);
+	of_node_put(root);
+	if (ret)
+		goto free_soc;
+
+	soc_dev_attr->revision = kasprintf(GFP_KERNEL, "%d",
+					exynos_soc_info.revision);
+	if (!soc_dev_attr->revision)
+		goto free_soc;
+
+	soc_dev_attr->soc_id = product_id_to_name(exynos_soc_info.product_id);
+
+	soc_dev = soc_device_register(soc_dev_attr);
+	if (IS_ERR(soc_dev))
+		goto free_rev;
+
+	soc_device_to_device(soc_dev);
+
+	dev_info(&pdev->dev, "Exynos: CPU[%s] CPU_REV[0x%x] Detected\n",
+			product_id_to_name(exynos_soc_info.product_id),
+			exynos_soc_info.revision);
+	return 0;
+free_rev:
+	kfree(soc_dev_attr->revision);
+free_soc:
+	kfree(soc_dev_attr);
+	return -EINVAL;
+}
+
+static struct platform_driver exynos_chipid_driver __initdata = {
+	.driver = {
+		.name = "exynos-chipid",
+		.of_match_table = of_exynos_chipid_ids,
+	},
+	.probe = exynos_chipid_probe,
+};
+
+static int __init exynos_chipid_init(void)
+{
+	return platform_driver_register(&exynos_chipid_driver);
+}
+core_initcall(exynos_chipid_init);
+
diff --git a/include/linux/soc/samsung/exynos-soc.h b/include/linux/soc/samsung/exynos-soc.h
new file mode 100644
index 0000000..d2d9f05
--- /dev/null
+++ b/include/linux/soc/samsung/exynos-soc.h
@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * Header for EXYNOS SoC Chipid support
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __EXYNOS_SOC_H
+#define __EXYNOS_SOC_H
+
+#define EXYNOS3250_SOC_ID	0xE3472000
+#define EXYNOS4210_SOC_ID	0x43210000
+#define EXYNOS4212_SOC_ID	0x43220000
+#define EXYNOS4412_SOC_ID	0xE4412000
+#define EXYNOS4415_SOC_ID	0xE4415000
+#define EXYNOS5250_SOC_ID	0x43520000
+#define EXYNOS5260_SOC_ID	0xE5260000
+#define EXYNOS5410_SOC_ID	0xE5410000
+#define EXYNOS5420_SOC_ID	0xE5420000
+#define EXYNOS5440_SOC_ID	0xE5440000
+#define EXYNOS5800_SOC_ID	0xE5422000
+
+#define EXYNOS_SOC_MASK		0xFFFFF000
+
+#define EXYNOS4210_REV_0	0x0
+#define EXYNOS4210_REV_1_0	0x10
+#define EXYNOS4210_REV_1_1	0x11
+
+/**
+ * Struct exynos_chipid_info
+ * @soc_product_id: product id allocated to exynos SoC
+ * @soc_revision: revision of exynos SoC
+ */
+
+struct exynos_chipid_info {
+	u32 product_id;
+	u32 revision;
+};
+
+extern struct exynos_chipid_info exynos_soc_info;
+
+/* Since we need chipid to be initialized as early as possible
+ * during secondary core bootup adding early initialization function
+ */
+extern void exynos_chipid_early_init(struct device *dev);
+
+#endif /* __EXYNOS_SOC_H */
-- 
2.2.0