From: Arul Ramasamy <Arul.Ramasamy@xxxxxxxxxx>
The Pistachio SoC from Imagination Technologies includes a generic eFuse
Controller which exposes the status of 128 EFUSE bits to the external world.
Signed-off-by: Arul Ramasamy <Arul.Ramasamy@xxxxxxxxxx>
Signed-off-by: Jude Abraham <Jude.Abraham@xxxxxxxxxx>
Signed-off-by: Naidu Tellapati <Naidu.Tellapati@xxxxxxxxxx>
---
drivers/soc/Kconfig | 1 +
drivers/soc/Makefile | 1 +
drivers/soc/img/Makefile | 1 +
drivers/soc/img/fuse/Kconfig | 9 ++
drivers/soc/img/fuse/Makefile | 1 +
drivers/soc/img/fuse/img-efuse.c | 192 +++++++++++++++++++++++++++++++++++++++
include/soc/img/img-efuse.h | 15 +++
7 files changed, 220 insertions(+)
create mode 100644 drivers/soc/img/Makefile
create mode 100644 drivers/soc/img/fuse/Kconfig
create mode 100644 drivers/soc/img/fuse/Makefile
create mode 100644 drivers/soc/img/fuse/img-efuse.c
create mode 100644 include/soc/img/img-efuse.h
diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index 76d6bd4..b699082 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -1,5 +1,6 @@
menu "SOC (System On Chip) specific Drivers"
+source "drivers/soc/img/fuse/Kconfig"
source "drivers/soc/qcom/Kconfig"
source "drivers/soc/ti/Kconfig"
source "drivers/soc/versatile/Kconfig"
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index 063113d..eed9585 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -2,6 +2,7 @@
# Makefile for the Linux Kernel SOC specific device drivers.
#
+obj-$(CONFIG_SOC_IMG) += img/
obj-$(CONFIG_ARCH_QCOM) += qcom/
obj-$(CONFIG_ARCH_TEGRA) += tegra/
obj-$(CONFIG_SOC_TI) += ti/
diff --git a/drivers/soc/img/Makefile b/drivers/soc/img/Makefile
new file mode 100644
index 0000000..f33a89f
--- /dev/null
+++ b/drivers/soc/img/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_SOC_IMG) += fuse/
diff --git a/drivers/soc/img/fuse/Kconfig b/drivers/soc/img/fuse/Kconfig
new file mode 100644
index 0000000..7810ea3
--- /dev/null
+++ b/drivers/soc/img/fuse/Kconfig
@@ -0,0 +1,9 @@
+config IMG_EFUSE
+ tristate "Imagination Technologies Generic eFuse driver"
+ depends on HAS_IOMEM
+ help
+ Imagination Technologies Generic eFuse driver which exposes the status
+ of 128 EFUSE bits.
+
+ To compile this driver as a module, choose M here: the module will
+ be called img-efuse.
diff --git a/drivers/soc/img/fuse/Makefile b/drivers/soc/img/fuse/Makefile
new file mode 100644
index 0000000..e873dc0
--- /dev/null
+++ b/drivers/soc/img/fuse/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_IMG_EFUSE) += img-efuse.o
diff --git a/drivers/soc/img/fuse/img-efuse.c b/drivers/soc/img/fuse/img-efuse.c
new file mode 100644
index 0000000..de08b64
--- /dev/null
+++ b/drivers/soc/img/fuse/img-efuse.c
@@ -0,0 +1,192 @@
+/*
+ * Imagination Technologies Generic eFuse driver
+ *
+ * Copyright (c) 2014 Imagination Technologies Ltd.
+ *
+ * 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.
+ *
+ * Based on drivers/misc/eeprom/sunxi_sid.c Copyright (c) 2013 Oliver Schinagl
+ */
+#include <linux/clk.h>
+#include <linux/compiler.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/kobject.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/stat.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+
+#include <soc/img/img-efuse.h>
+
+#define DRV_NAME "img-efuse"
+
+struct img_efuse {
+ void __iomem *base;
+ unsigned int size;
+ struct clk *osc_clk;
+ struct clk *sys_clk;
+};
+
+struct img_efuse *efuse_dev;
+
+static u8 img_efuse_read_byte(const unsigned int offset)
+{
+ u32 data;
+
+ if (offset >= efuse_dev->size)
+ return 0;
+
+ data = readl(efuse_dev->base + round_down(offset, 4));
+ data >>= (offset % 4) * 8;
+
+ return data; /* Only return the last byte */
+}
+
+int img_efuse_readl(unsigned int offset, u32 *value)
+{
+ if (!efuse_dev || IS_ERR(efuse_dev->base))
+ return -ENODEV;
+
+ if ((offset > (efuse_dev->size - 4)) || (offset % 4 != 0))
+ return -EINVAL;
+
+ *value = readl(efuse_dev->base + offset);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(img_efuse_readl);
+
+static ssize_t img_efuse_read(struct file *fd, struct kobject *kobj,
+ struct bin_attribute *attr, char *buf,
+ loff_t pos, size_t size)
+{
+ int i;
+ struct platform_device *pdev;
+ struct img_efuse *efuse;
+
+ pdev = to_platform_device(kobj_to_dev(kobj));
+ efuse = platform_get_drvdata(pdev);
+
+ if (pos < 0 || pos >= efuse->size)
+ return 0;
+
+ if (size > efuse->size - pos)
+ size = efuse->size - pos;
+
+ for (i = 0; i < size; i++)
+ buf[i] = img_efuse_read_byte(pos + i);
+
+ return i;
+}
+
+static struct bin_attribute img_efuse_bin_attr = {
+ .attr = { .name = "efuse", .mode = S_IRUGO, },
+ .read = img_efuse_read,
+};
+
+static int img_efuse_remove(struct platform_device *pdev)
+{
+ struct img_efuse *efuse;
+
+ efuse = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(efuse->osc_clk);
+ clk_disable_unprepare(efuse->sys_clk);
+
+ device_remove_bin_file(&pdev->dev, &img_efuse_bin_attr);
+
+ return 0;
+}
+
+static const struct of_device_id img_efuse_of_match[] = {
+ { .compatible = "img,efuse", .data = (void *)16},
+ {/* sentinel */},
+};
+MODULE_DEVICE_TABLE(of, img_efuse_of_match);
+
+static int img_efuse_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct resource *res;
+ const struct of_device_id *of_dev_id;
+
+ efuse_dev = devm_kzalloc(&pdev->dev, sizeof(struct img_efuse *),
+ GFP_KERNEL);
+ if (!efuse_dev)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ efuse_dev->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(efuse_dev->base))
+ return PTR_ERR(efuse_dev->base);
+
+ of_dev_id = of_match_device(img_efuse_of_match, &pdev->dev);
+ if (!of_dev_id)
+ return -ENODEV;
+ efuse_dev->size = (int)of_dev_id->data;
+
+ efuse_dev->sys_clk = devm_clk_get(&pdev->dev, "sys");
+ if (IS_ERR(efuse_dev->sys_clk)) {
+ dev_err(&pdev->dev, "failed to get system clock");
+ return PTR_ERR(efuse_dev->sys_clk);
+ }
+
+ efuse_dev->osc_clk = devm_clk_get(&pdev->dev, "osc");
+ if (IS_ERR(efuse_dev->osc_clk)) {
+ dev_err(&pdev->dev, "failed to get oscillator clock");
+ return PTR_ERR(efuse_dev->osc_clk);
+ }
+
+ ret = clk_prepare_enable(efuse_dev->sys_clk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "could not enable system clock.\n");
+ return ret;
+ }
+
+ ret = clk_prepare_enable(efuse_dev->osc_clk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "could not enable oscillator clock.\n");
+ goto disable_sysclk;
+ }
+
+ platform_set_drvdata(pdev, efuse_dev);
+
+ img_efuse_bin_attr.size = efuse_dev->size;
+ if (device_create_bin_file(&pdev->dev, &img_efuse_bin_attr)) {
+ ret = -ENODEV;
+ goto disable_oscclk;
+ }
+
+ return 0;
+
+disable_oscclk:
+ clk_disable_unprepare(efuse_dev->osc_clk);
+disable_sysclk:
+ clk_disable_unprepare(efuse_dev->sys_clk);
+ return ret;
+}
+
+static struct platform_driver img_efuse_driver = {
+ .probe = img_efuse_probe,
+ .remove = img_efuse_remove,
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = img_efuse_of_match,
+ },
+};
+module_platform_driver(img_efuse_driver);
+
+MODULE_AUTHOR("Arul Ramasamy<Arul.Ramasamy@xxxxxxxxxx>");
+MODULE_AUTHOR("Jude Abraham<Jude.Abraham@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Imagination Technologies Generic eFuse driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/soc/img/img-efuse.h b/include/soc/img/img-efuse.h
new file mode 100644
index 0000000..64bf4ad
--- /dev/null
+++ b/include/soc/img/img-efuse.h
@@ -0,0 +1,15 @@
+/*
+ * Imagination Technologies Generic eFuse driver
+ *
+ * Copyright (C) 2014 Imagination Technologies Ltd.
+ *
+ * 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 __IMG_EFUSE_H
+#define __IMG_EFUSE_H
+
+int img_efuse_readl(unsigned int offset, u32 *value);
+
+#endif
--
1.9.1
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