ENGR00123744-1 iMX23 add unique ID support

copy file from stmp plat

Signed-off-by: Frank Li <Frank.Li@freescale.com>

3 files changed, 662 insertions, 0 deletions

diff --git a/arch/arm/mach-mx23/otp.c b/arch/arm/mach-mx23/otp.c
new file mode 100644
index 000000000000..e9ae4a7d8858
--- /dev/null
+++ b/arch/arm/mach-mx23/otp.c
@@ -0,0 +1,434 @@
+/*
+ * Unique ID manipulation: Freescale STMP378X OTP bits read/write procedures
+ *
+ * Author: dmitry pervushin <dimka@embeddedalley.com>
+ *
+ * Copyright 2008-2010 Freescale Semiconductor, Inc.
+ * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
+ */
+
+/*
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+#include <linux/kobject.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/fcntl.h>
+#include <linux/mutex.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+
+#include <mach/unique-id.h>
+#include <mach/regs-ocotp.h>
+#include <mach/regs-power.h>
+#include <mach/platform.h>
+
+static DEFINE_MUTEX(otp_mutex);
+static unsigned otp_mode;
+static unsigned long otp_hclk_saved;
+static u32 otp_voltage_saved;
+
+static int otp_full; /* = 0. By default, show/set only customer bits */
+#define OTP_USER_OFFSET 0
+#define OTP_USER_SIZE	4
+
+/**
+ * otp_wait_busy - wait for completion of operation
+ *
+ * @flags: flags that should be clear in addition to _BUSY and _ERROR
+ *
+ * Returns 0 on success or -ETIMEDOUT on error
+ **/
+static int otp_wait_busy(u32 flags)
+{
+	int count;
+	u32 c;
+
+	for (count = 10000; count >= 0; count--) {
+		c = __raw_readl(REGS_OCOTP_BASE + HW_OCOTP_CTRL);
+		if (!(c & (BM_OCOTP_CTRL_BUSY | BM_OCOTP_CTRL_ERROR | flags)))
+			break;
+		cpu_relax();
+	}
+	if (count < 0)
+		return -ETIMEDOUT;
+	return 0;
+}
+
+/**
+ * otp_open - open OTP bits for read or write access
+ *
+ * @mode: either O_RDONLY or O_WRONLY
+ *
+ * Returns 0 on success, error code otherwise
+ **/
+static int otp_open(int mode)
+{
+	int r;
+	struct clk *hclk;
+	int err;
+
+	if (!mutex_trylock(&otp_mutex)) {
+		printk(KERN_ERR"%s: already opened\n", __func__);
+		return -EAGAIN;
+	}
+
+	if (mode == O_RDONLY) {
+		pr_debug("%s: read-only mode\n", __func__);
+
+		r = otp_wait_busy(0);
+		if (r) {
+			err = -ETIMEDOUT;
+			goto out;
+		}
+
+		/* 2. Set RD_BANK_OPEN */
+		stmp3xxx_setl(BM_OCOTP_CTRL_RD_BANK_OPEN, REGS_OCOTP_BASE + HW_OCOTP_CTRL);
+		udelay(10);
+
+		otp_wait_busy(0);
+	}
+
+	else if (mode == O_WRONLY) {
+		pr_debug("%s: write-only mode\n", __func__);
+		hclk = clk_get(NULL, "hclk");
+		if (IS_ERR(hclk)) {
+			err = PTR_ERR(hclk);
+			goto out;
+		}
+
+		/*
+		   WARNING  ACHTUNG  UWAGA
+
+		   the code below changes HCLK clock rate to 24M. This is
+		   required to write OTP bits (7.2.2 in STMP378x Target
+		   Specification), and might affect LCD operation, for example.
+		   Moreover, this hacky code changes VDDIO to 2.8V; and resto-
+		   res it only on otp_close(). This may affect... anything.
+
+		   You are warned now.
+		 */
+		otp_hclk_saved = clk_get_rate(hclk);
+		clk_set_rate(hclk, 24000);
+		/* Set the voltage to 2.8V */
+		otp_voltage_saved = __raw_readl(REGS_POWER_BASE + HW_POWER_VDDIOCTRL);
+		__raw_writel(
+			(otp_voltage_saved & ~BM_POWER_VDDIOCTRL_TRG) | 0x00, REGS_POWER_BASE + HW_POWER_VDDIOCTRL);
+
+		r = otp_wait_busy(BM_OCOTP_CTRL_RD_BANK_OPEN);
+		if (r < 0) {
+			__raw_writel(otp_voltage_saved, REGS_POWER_BASE + HW_POWER_VDDIOCTRL);
+			clk_set_rate(hclk, otp_hclk_saved);
+			clk_put(hclk);
+			err = -ETIMEDOUT;
+			goto out;
+		}
+
+		clk_put(hclk);
+	}
+
+	else {
+		pr_debug("%s: unknown mode '%d'\n", __func__, mode);
+		err = -EINVAL;
+		goto out;
+	}
+
+	otp_mode = mode;
+	return 0;
+out:
+	mutex_unlock(&otp_mutex);
+	pr_debug("%s: status %d\n", __func__, err);
+	return err;
+}
+
+/**
+ * otp_close - close the OTP bits after opening by otp_open
+ **/
+static void otp_close(void)
+{
+	struct clk *hclk;
+
+	if (!mutex_is_locked(&otp_mutex)) {
+		printk(KERN_ERR"%s: wasn't opened\n", __func__);
+		return;
+	}
+
+	if (otp_mode == O_RDONLY) {
+		/* 5. clear RD_BANK_OPEN */
+		stmp3xxx_clearl(BM_OCOTP_CTRL_RD_BANK_OPEN, REGS_OCOTP_BASE + HW_OCOTP_CTRL);
+	}
+
+	else if (otp_mode == O_WRONLY) {
+		hclk = clk_get(NULL, "hclk");
+		clk_set_rate(hclk, otp_hclk_saved);
+		__raw_writel(otp_voltage_saved, REGS_POWER_BASE + HW_POWER_VDDIOCTRL);
+		otp_wait_busy(0);
+		stmp3xxx_setl(BM_OCOTP_CTRL_RELOAD_SHADOWS, REGS_OCOTP_BASE + HW_OCOTP_CTRL);
+		otp_wait_busy(BM_OCOTP_CTRL_RELOAD_SHADOWS);
+	}
+
+	else {
+		return; /* -EINVAL. Who does really check close? */
+	}
+
+	otp_mode = 0;
+	mutex_unlock(&otp_mutex);
+}
+
+/**
+ * otp_read_bits - read the content of OTP
+ *
+ * @start: offset from 0, in u32's
+ * @len: number of OTP u32's to read
+ * @bits: caller-allocated buffer to save bits
+ * @size: size of @bits
+ *
+ * Returns number of u32's saved to buffer
+ **/
+static size_t otp_read_bits(int start, int len, u32 *bits, size_t size)
+{
+	int ofs;
+
+	BUG_ON(!mutex_is_locked(&otp_mutex));
+
+	/* read all stuff that caller needs */
+	if (start + len > 4 * 8)  		/* 4 banks, 8 registers each */
+		len = 4 * 8 - start;
+
+	for (ofs = start; ofs < len; ofs++) {
+		if (size/sizeof(*bits) <= 0)	/* we drained out the buffer */
+			break;
+		*bits = __raw_readl(REGS_OCOTP_BASE + HW_OCOTP_CUSTn(ofs));
+		bits++;
+		size -= sizeof(*bits);
+	}
+
+	return ofs - start;	/* number of u32's that we saved to buffer */
+}
+
+/**
+ * otp_write_bits - store OTP bits
+ *
+ * @offset: offset from 0, in u32's
+ * @data: the u32 to write
+ * @magic: the magic value to be stored in UNLOCK field
+ *
+ **/
+static int otp_write_bits(int offset, u32 data, u32 magic)
+{
+	u32 c;
+	int r;
+
+	BUG_ON(!mutex_is_locked(&otp_mutex));
+
+	if (offset < 0 || offset > 0x1F)
+		return -EINVAL;
+
+	c = __raw_readl(REGS_OCOTP_BASE + HW_OCOTP_CTRL);
+	c &= ~BM_OCOTP_CTRL_ADDR;
+	c |= BF(offset, OCOTP_CTRL_ADDR);
+	c |= BF(magic, OCOTP_CTRL_WR_UNLOCK);
+	__raw_writel(c, REGS_OCOTP_BASE + HW_OCOTP_CTRL);
+
+	__raw_writel(data, REGS_OCOTP_BASE + HW_OCOTP_DATA);
+
+	r = otp_wait_busy(0);
+	if (r < 0)
+		return r;
+
+	udelay(2);
+	return 0;
+}
+
+static ssize_t otp_id_show(void *context, char *page, int ascii)
+{
+	char s[60];
+	int ret;
+	int n, i, j, r;
+	u32 otp_bits[4 * 8];
+
+	r = otp_open(O_RDONLY);
+	if (r < 0)
+		return 0;
+	n = otp_read_bits(0, 4 * 8, otp_bits, sizeof(otp_bits));
+	otp_close();
+
+	ret = 0;
+
+
+	if (ascii) {
+
+		strcpy(page, "");
+		ret = 0;
+
+		if (otp_full) {
+			for (i = 0; i < 4; i++) {
+
+				ret += sprintf(s, "Bank %d: ", i);
+				strcat(page, s);
+
+				for (j = 0; j < 8; j++) {
+
+					if (i * 4 + j > n)
+						break;
+					ret += sprintf(s, "%08X ",
+						otp_bits[i * 4 + j]);
+					strcat(page, s);
+				}
+
+				strcat(page, "\n");
+				ret++;
+			}
+		} else {
+			for (i = 0; i < OTP_USER_SIZE; i++) {
+				ret += sprintf(s, "%08X ",
+					otp_bits[i + OTP_USER_OFFSET]);
+				strcat(page, s);
+			}
+			strcat(page, "\n");
+			ret++;
+		}
+	} else {
+
+		if (otp_full) {
+			memcpy(page, otp_bits, sizeof(otp_bits));
+			ret = sizeof(otp_bits);
+		} else {
+			memcpy(page, otp_bits + OTP_USER_OFFSET,
+					OTP_USER_SIZE * sizeof(u32));
+			ret = OTP_USER_SIZE * sizeof(u32);
+		}
+	}
+
+	return ret;
+}
+
+static int otp_check_dry_run(const char *page, size_t count)
+{
+	if (count >= 3 && memcmp(page, "+++", 3) == 0)
+		return 3;
+	return 0;
+}
+
+static ssize_t otp_id_store(void *context, const char *page,
+				size_t count, int ascii)
+{
+	int r = 0;
+	const char *p, *cp, *d;
+	unsigned long index, value;
+	char tmps[20];	/* subject of strtoul */
+	int dry_run;
+
+	r = otp_open(O_WRONLY);
+	if (r < 0) {
+		printk(KERN_ERR"Cannot open OTP in WRITE mode\n");
+		return r;
+	}
+
+	if (ascii) {
+
+		dry_run = otp_check_dry_run(page, count);
+		if (dry_run > 0)
+			page += dry_run;
+
+		index = 0;
+		cp = page;
+
+		memset(tmps, 0, sizeof(tmps));
+
+		for (index = 0, cp = page; cp != NULL; index++) {
+			p = strchr(cp, ',');
+
+			d = strchr(cp, ':');
+			if (d && (!p || d < p)) {
+				strncpy(tmps, cp,
+					min_t(int, d - cp, sizeof(tmps) - 1));
+				r = strict_strtoul(tmps, 0, &index);
+				if (r < 0) {
+					pr_debug("Cannot parse '%s'\n", tmps);
+					break;
+				}
+				cp = d + 1;
+			}
+
+			memset(tmps, 0, sizeof(tmps));
+
+			if (!p)
+				strncpy(tmps, cp, sizeof(tmps));
+			else
+				strncpy(tmps, cp,
+					min_t(int, p - cp, sizeof(tmps) - 1));
+			r = strict_strtoul(tmps, 0, &value);
+			if (r < 0) {
+				pr_debug("Cannot parse '%s'\n", tmps);
+				break;
+			}
+
+			memset(tmps, 0, sizeof(tmps));
+
+			cp = p ? ++p : NULL;
+
+			if (!otp_full) {
+				index += OTP_USER_OFFSET;
+				if (index > OTP_USER_SIZE) {
+					printk(KERN_ERR"Cannot write at "
+							"offset %ld\n", index);
+					continue;
+				}
+			}
+
+			r = 0;
+			if (!dry_run) {
+				pr_debug("Index %ld, value 0x%08lx\n",
+						index, value);
+				r = otp_write_bits(index, value, 0x3e77);
+			} else
+				printk(KERN_NOTICE
+					"Dry-run: writing 0x%08lX => [%ld]\n",
+						value, index);
+			if (r < 0)
+				break;
+		}
+	} else {
+		printk(KERN_ERR"Binary write is not supported\n");
+		r = -ENOSYS;
+	}
+	otp_close();
+	return (r >= 0) ? count : r;
+}
+
+static struct uid_ops otp_ops = {
+	.id_show = otp_id_show,
+	.id_store = otp_id_store,
+};
+
+static int __init_or_module otp_init(void)
+{
+	void *p;
+
+	mutex_init(&otp_mutex);
+	p = uid_provider_init("otp", &otp_ops, NULL);
+	if (IS_ERR(p))
+		return PTR_ERR(p);
+	return 0;
+}
+
+static void __exit otp_remove(void)
+{
+	uid_provider_remove("otp");
+}
+
+module_param(otp_full, int, 0600);
+module_init(otp_init);
+module_exit(otp_remove);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("dmitry pervushin <dimka@embeddedalley.com>");
+MODULE_DESCRIPTION("Unique ID: OTP");
diff --git a/arch/arm/plat-mxs/include/mach/unique-id.h b/arch/arm/plat-mxs/include/mach/unique-id.h
new file mode 100644
index 000000000000..de5e04342ef5
--- /dev/null
+++ b/arch/arm/plat-mxs/include/mach/unique-id.h
@@ -0,0 +1,30 @@
+/*
+ * Unique ID interface for ID storage providers
+ *
+ * Embedded Alley Solutions, Inc <source@embeddedalley.com>
+ *
+ * Copyright 2008-2010 Freescale Semiconductor, Inc.
+ * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
+ */
+
+/*
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+#ifndef __UNIQUE_ID_H
+#define __UNIQUE_ID_H
+
+struct uid_ops {
+	ssize_t (*id_show)(void *context, char *page, int ascii);
+	ssize_t (*id_store)(void *context, const char *page,
+			size_t count, int ascii);
+};
+
+struct kobject *uid_provider_init(const char *name,
+		struct uid_ops *ops, void *context);
+void uid_provider_remove(const char *name);
+#endif
diff --git a/arch/arm/plat-mxs/unique-id.c b/arch/arm/plat-mxs/unique-id.c
new file mode 100644
index 000000000000..35c0fcdab605
--- /dev/null
+++ b/arch/arm/plat-mxs/unique-id.c
@@ -0,0 +1,198 @@
+/*
+ * Unique ID manipulation sysfs access generic functions
+ *
+ * Author: dmitry pervushin <dimka@embeddedalley.com>
+ *
+ * Copyright 2008-2010 Freescale Semiconductor, Inc.
+ * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
+ */
+
+/*
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+#include <linux/kobject.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/err.h>
+#include <linux/timer.h>
+#include <linux/spinlock.h>
+
+#include <mach/unique-id.h>
+
+static int unlock;
+static spinlock_t u_lock;
+static const unsigned long UID_AUTOLOCK_TIMEOUT = HZ * 60 * 3;
+static struct timer_list u_timer;
+
+static void uid_timer_autolock(unsigned long param)
+{
+	struct timer_list *tmr = (struct timer_list *)param;
+
+	if (spin_trylock(&u_lock)) {
+		if (unlock)
+			pr_debug("%s: locked down.\n", __func__);
+		unlock = 0;
+		spin_unlock(&u_lock);
+	}
+	mod_timer(tmr, jiffies + UID_AUTOLOCK_TIMEOUT);
+}
+
+static LIST_HEAD(uid_provider_list);
+
+struct uid_provider {
+	struct kobject 	*kobj;
+	struct list_head list;
+	struct uid_ops  *ops;
+	void *context;
+};
+
+static struct uid_provider *uid_provider_find(const char *name);
+
+#define UID_FWD_SYSFS_FILE(var, file, param) \
+	static ssize_t var##_show(struct kobject *kobj, 		\
+			struct kobj_attribute *attr, char *buf) 	\
+	{								\
+		struct uid_provider *p = 				\
+			uid_provider_find(kobject_name(kobj));		\
+		ssize_t r;						\
+		BUG_ON(p == NULL);					\
+		r = (p->ops && p->ops->file##_show) ? 			\
+			p->ops->file##_show(p->context, buf, param) : 0;\
+		return r;						\
+	}								\
+									\
+	static ssize_t var##_store(struct kobject *kobj, 		\
+		struct kobj_attribute *attr, const char *buf, 		\
+			size_t count)					\
+	{								\
+		struct uid_provider *p =				\
+			uid_provider_find(kobject_name(kobj));		\
+		ssize_t r;						\
+		int ul;							\
+		BUG_ON(p == NULL);					\
+		spin_lock(&u_lock);					\
+		ul = unlock;						\
+		spin_unlock(&u_lock);					\
+		if (ul) 						\
+			r =  (p->ops && p->ops->file##_store) ? 	\
+		    p->ops->file##_store(p->context, buf, count, param) \
+				: count;				\
+		else							\
+			r = -EACCES;					\
+		return r;						\
+	}
+
+struct kobject *uid_kobj;
+
+#define UID_ATTR(_name, _varname) \
+	static struct kobj_attribute _varname##_attr = \
+		__ATTR(_name, 0644, _varname##_show, _varname##_store)
+
+UID_FWD_SYSFS_FILE(id, id, 1);
+UID_FWD_SYSFS_FILE(id_bin, id, 0);
+UID_ATTR(id, id);
+UID_ATTR(id.bin, id_bin);
+
+static struct attribute *uid_attrs[] = {
+	&id_attr.attr,
+	&id_bin_attr.attr,
+	NULL
+};
+
+static struct attribute_group uid_attr_group = {
+	.attrs = uid_attrs,
+};
+
+struct kobject *uid_provider_init(const char *name,
+			struct uid_ops *ops, void *context)
+{
+	struct uid_provider *new;
+	int err;
+
+	new = kzalloc(sizeof(*new), GFP_KERNEL);
+	if (!new) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	new->kobj = kobject_create_and_add(name, uid_kobj);
+	if (!new->kobj) {
+		err = -ENOMEM;
+		goto out;
+	}
+	new->ops = ops;
+	new->context = context;
+
+	err = sysfs_create_group(new->kobj, &uid_attr_group);
+	if (err)
+		goto out2;
+
+	list_add_tail(&new->list, &uid_provider_list);
+	return new->kobj;
+out2:
+	kobject_del(new->kobj);
+out:
+	kfree(new);
+	return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(uid_provider_init);
+
+static struct uid_provider *uid_provider_find(const char *name)
+{
+	struct uid_provider *p;
+
+	list_for_each_entry(p, &uid_provider_list, list) {
+		if (strcmp(kobject_name(p->kobj), name) == 0)
+			return p;
+	}
+	return NULL;
+}
+
+void uid_provider_remove(const char *name)
+{
+	struct uid_provider *p;
+
+	p = uid_provider_find(name);
+	if (!p)
+		return;
+	kobject_del(p->kobj);
+	list_del(&p->list);
+	kfree(p);
+}
+EXPORT_SYMBOL_GPL(uid_provider_remove);
+
+static int uid_sysfs_init(void)
+{
+	int error;
+
+	uid_kobj = kobject_create_and_add("uid", NULL);
+	if (!uid_kobj) {
+		error = -ENOMEM;
+		goto out1;
+	}
+
+	spin_lock_init(&u_lock);
+	setup_timer(&u_timer, uid_timer_autolock, (unsigned long)&u_timer);
+
+	/* try to lock each 3 minutes */
+	mod_timer(&u_timer, jiffies + UID_AUTOLOCK_TIMEOUT);
+	return 0;
+
+out1:
+	printk(KERN_ERR"%s failed, error %d.", __func__, error);
+	return error;
+}
+
+module_param(unlock, int, 0600)
+core_initcall(uid_sysfs_init);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("dmitry pervushin <dimka@embeddedalley.com>");
+MODULE_DESCRIPTION("Unique ID simple framework");