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authorSrikant Patnaik2015-01-11 12:28:04 +0530
committerSrikant Patnaik2015-01-11 12:28:04 +0530
commit871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch)
tree8718f573808810c2a1e8cb8fb6ac469093ca2784 /drivers/mtd/devices/phram.c
parent9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff)
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Moved, renamed, and deleted files
The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure.
Diffstat (limited to 'drivers/mtd/devices/phram.c')
-rw-r--r--drivers/mtd/devices/phram.c302
1 files changed, 302 insertions, 0 deletions
diff --git a/drivers/mtd/devices/phram.c b/drivers/mtd/devices/phram.c
new file mode 100644
index 00000000..67823de6
--- /dev/null
+++ b/drivers/mtd/devices/phram.c
@@ -0,0 +1,302 @@
+/**
+ * Copyright (c) ???? Jochen Schäuble <psionic@psionic.de>
+ * Copyright (c) 2003-2004 Joern Engel <joern@wh.fh-wedel.de>
+ *
+ * Usage:
+ *
+ * one commend line parameter per device, each in the form:
+ * phram=<name>,<start>,<len>
+ * <name> may be up to 63 characters.
+ * <start> and <len> can be octal, decimal or hexadecimal. If followed
+ * by "ki", "Mi" or "Gi", the numbers will be interpreted as kilo, mega or
+ * gigabytes.
+ *
+ * Example:
+ * phram=swap,64Mi,128Mi phram=test,900Mi,1Mi
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <asm/io.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/slab.h>
+#include <linux/mtd/mtd.h>
+
+struct phram_mtd_list {
+ struct mtd_info mtd;
+ struct list_head list;
+};
+
+static LIST_HEAD(phram_list);
+
+static int phram_erase(struct mtd_info *mtd, struct erase_info *instr)
+{
+ u_char *start = mtd->priv;
+
+ memset(start + instr->addr, 0xff, instr->len);
+
+ /*
+ * This'll catch a few races. Free the thing before returning :)
+ * I don't feel at all ashamed. This kind of thing is possible anyway
+ * with flash, but unlikely.
+ */
+ instr->state = MTD_ERASE_DONE;
+ mtd_erase_callback(instr);
+ return 0;
+}
+
+static int phram_point(struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, void **virt, resource_size_t *phys)
+{
+ *virt = mtd->priv + from;
+ *retlen = len;
+ return 0;
+}
+
+static int phram_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
+{
+ return 0;
+}
+
+static int phram_read(struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, u_char *buf)
+{
+ u_char *start = mtd->priv;
+
+ memcpy(buf, start + from, len);
+ *retlen = len;
+ return 0;
+}
+
+static int phram_write(struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const u_char *buf)
+{
+ u_char *start = mtd->priv;
+
+ memcpy(start + to, buf, len);
+ *retlen = len;
+ return 0;
+}
+
+static void unregister_devices(void)
+{
+ struct phram_mtd_list *this, *safe;
+
+ list_for_each_entry_safe(this, safe, &phram_list, list) {
+ mtd_device_unregister(&this->mtd);
+ iounmap(this->mtd.priv);
+ kfree(this->mtd.name);
+ kfree(this);
+ }
+}
+
+static int register_device(char *name, unsigned long start, unsigned long len)
+{
+ struct phram_mtd_list *new;
+ int ret = -ENOMEM;
+
+ new = kzalloc(sizeof(*new), GFP_KERNEL);
+ if (!new)
+ goto out0;
+
+ ret = -EIO;
+ new->mtd.priv = ioremap(start, len);
+ if (!new->mtd.priv) {
+ pr_err("ioremap failed\n");
+ goto out1;
+ }
+
+
+ new->mtd.name = name;
+ new->mtd.size = len;
+ new->mtd.flags = MTD_CAP_RAM;
+ new->mtd._erase = phram_erase;
+ new->mtd._point = phram_point;
+ new->mtd._unpoint = phram_unpoint;
+ new->mtd._read = phram_read;
+ new->mtd._write = phram_write;
+ new->mtd.owner = THIS_MODULE;
+ new->mtd.type = MTD_RAM;
+ new->mtd.erasesize = PAGE_SIZE;
+ new->mtd.writesize = 1;
+
+ ret = -EAGAIN;
+ if (mtd_device_register(&new->mtd, NULL, 0)) {
+ pr_err("Failed to register new device\n");
+ goto out2;
+ }
+
+ list_add_tail(&new->list, &phram_list);
+ return 0;
+
+out2:
+ iounmap(new->mtd.priv);
+out1:
+ kfree(new);
+out0:
+ return ret;
+}
+
+static int ustrtoul(const char *cp, char **endp, unsigned int base)
+{
+ unsigned long result = simple_strtoul(cp, endp, base);
+
+ switch (**endp) {
+ case 'G':
+ result *= 1024;
+ case 'M':
+ result *= 1024;
+ case 'k':
+ result *= 1024;
+ /* By dwmw2 editorial decree, "ki", "Mi" or "Gi" are to be used. */
+ if ((*endp)[1] == 'i')
+ (*endp) += 2;
+ }
+ return result;
+}
+
+static int parse_num32(uint32_t *num32, const char *token)
+{
+ char *endp;
+ unsigned long n;
+
+ n = ustrtoul(token, &endp, 0);
+ if (*endp)
+ return -EINVAL;
+
+ *num32 = n;
+ return 0;
+}
+
+static int parse_name(char **pname, const char *token)
+{
+ size_t len;
+ char *name;
+
+ len = strlen(token) + 1;
+ if (len > 64)
+ return -ENOSPC;
+
+ name = kmalloc(len, GFP_KERNEL);
+ if (!name)
+ return -ENOMEM;
+
+ strcpy(name, token);
+
+ *pname = name;
+ return 0;
+}
+
+
+static inline void kill_final_newline(char *str)
+{
+ char *newline = strrchr(str, '\n');
+ if (newline && !newline[1])
+ *newline = 0;
+}
+
+
+#define parse_err(fmt, args...) do { \
+ pr_err(fmt , ## args); \
+ return 1; \
+} while (0)
+
+/*
+ * This shall contain the module parameter if any. It is of the form:
+ * - phram=<device>,<address>,<size> for module case
+ * - phram.phram=<device>,<address>,<size> for built-in case
+ * We leave 64 bytes for the device name, 12 for the address and 12 for the
+ * size.
+ * Example: phram.phram=rootfs,0xa0000000,512Mi
+ */
+static __initdata char phram_paramline[64+12+12];
+
+static int __init phram_setup(const char *val)
+{
+ char buf[64+12+12], *str = buf;
+ char *token[3];
+ char *name;
+ uint32_t start;
+ uint32_t len;
+ int i, ret;
+
+ if (strnlen(val, sizeof(buf)) >= sizeof(buf))
+ parse_err("parameter too long\n");
+
+ strcpy(str, val);
+ kill_final_newline(str);
+
+ for (i=0; i<3; i++)
+ token[i] = strsep(&str, ",");
+
+ if (str)
+ parse_err("too many arguments\n");
+
+ if (!token[2])
+ parse_err("not enough arguments\n");
+
+ ret = parse_name(&name, token[0]);
+ if (ret)
+ return ret;
+
+ ret = parse_num32(&start, token[1]);
+ if (ret) {
+ kfree(name);
+ parse_err("illegal start address\n");
+ }
+
+ ret = parse_num32(&len, token[2]);
+ if (ret) {
+ kfree(name);
+ parse_err("illegal device length\n");
+ }
+
+ ret = register_device(name, start, len);
+ if (!ret)
+ pr_info("%s device: %#x at %#x\n", name, len, start);
+ else
+ kfree(name);
+
+ return ret;
+}
+
+static int __init phram_param_call(const char *val, struct kernel_param *kp)
+{
+ /*
+ * This function is always called before 'init_phram()', whether
+ * built-in or module.
+ */
+ if (strlen(val) >= sizeof(phram_paramline))
+ return -ENOSPC;
+ strcpy(phram_paramline, val);
+
+ return 0;
+}
+
+module_param_call(phram, phram_param_call, NULL, NULL, 000);
+MODULE_PARM_DESC(phram, "Memory region to map. \"phram=<name>,<start>,<length>\"");
+
+
+static int __init init_phram(void)
+{
+ if (phram_paramline[0])
+ return phram_setup(phram_paramline);
+
+ return 0;
+}
+
+static void __exit cleanup_phram(void)
+{
+ unregister_devices();
+}
+
+module_init(init_phram);
+module_exit(cleanup_phram);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Joern Engel <joern@wh.fh-wedel.de>");
+MODULE_DESCRIPTION("MTD driver for physical RAM");