summaryrefslogtreecommitdiffstats
path: root/arch/mips/bcm47xx/nvram.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/mips/bcm47xx/nvram.c')
-rw-r--r--arch/mips/bcm47xx/nvram.c94
1 files changed, 94 insertions, 0 deletions
diff --git a/arch/mips/bcm47xx/nvram.c b/arch/mips/bcm47xx/nvram.c
new file mode 100644
index 0000000..06e03b2
--- /dev/null
+++ b/arch/mips/bcm47xx/nvram.c
@@ -0,0 +1,94 @@
+/*
+ * BCM947xx nvram variable access
+ *
+ * Copyright (C) 2005 Broadcom Corporation
+ * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/ssb/ssb.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <asm/addrspace.h>
+#include <asm/mach-bcm47xx/nvram.h>
+#include <asm/mach-bcm47xx/bcm47xx.h>
+
+static char nvram_buf[NVRAM_SPACE];
+
+/* Probe for NVRAM header */
+static void __init early_nvram_init(void)
+{
+ struct ssb_mipscore *mcore = &ssb_bcm47xx.mipscore;
+ struct nvram_header *header;
+ int i;
+ u32 base, lim, off;
+ u32 *src, *dst;
+
+ base = mcore->flash_window;
+ lim = mcore->flash_window_size;
+
+ off = FLASH_MIN;
+ while (off <= lim) {
+ /* Windowed flash access */
+ header = (struct nvram_header *)
+ KSEG1ADDR(base + off - NVRAM_SPACE);
+ if (header->magic == NVRAM_HEADER)
+ goto found;
+ off <<= 1;
+ }
+
+ /* Try embedded NVRAM at 4 KB and 1 KB as last resorts */
+ header = (struct nvram_header *) KSEG1ADDR(base + 4096);
+ if (header->magic == NVRAM_HEADER)
+ goto found;
+
+ header = (struct nvram_header *) KSEG1ADDR(base + 1024);
+ if (header->magic == NVRAM_HEADER)
+ goto found;
+
+ return;
+
+found:
+ src = (u32 *) header;
+ dst = (u32 *) nvram_buf;
+ for (i = 0; i < sizeof(struct nvram_header); i += 4)
+ *dst++ = *src++;
+ for (; i < header->len && i < NVRAM_SPACE; i += 4)
+ *dst++ = le32_to_cpu(*src++);
+}
+
+int nvram_getenv(char *name, char *val, size_t val_len)
+{
+ char *var, *value, *end, *eq;
+
+ if (!name)
+ return 1;
+
+ if (!nvram_buf[0])
+ early_nvram_init();
+
+ /* Look for name=value and return value */
+ var = &nvram_buf[sizeof(struct nvram_header)];
+ end = nvram_buf + sizeof(nvram_buf) - 2;
+ end[0] = end[1] = '\0';
+ for (; *var; var = value + strlen(value) + 1) {
+ eq = strchr(var, '=');
+ if (!eq)
+ break;
+ value = eq + 1;
+ if ((eq - var) == strlen(name) &&
+ strncmp(var, name, (eq - var)) == 0) {
+ snprintf(val, val_len, "%s", value);
+ return 0;
+ }
+ }
+ return 1;
+}
+EXPORT_SYMBOL(nvram_getenv);
OpenPOWER on IntegriCloud