1 files changed, 148 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/pseries/nvram.c b/arch/powerpc/platforms/pseries/nvram.c
new file mode 100644
index 000000000000..18abfb1f4e24
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/nvram.c
@@ -0,0 +1,148 @@
+/*
+ *  c 2001 PPC 64 Team, IBM Corp
+ *
+ *      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.
+ *
+ * /dev/nvram driver for PPC64
+ *
+ * This perhaps should live in drivers/char
+ */
+
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <asm/uaccess.h>
+#include <asm/nvram.h>
+#include <asm/rtas.h>
+#include <asm/prom.h>
+#include <asm/machdep.h>
+
+static unsigned int nvram_size;
+static int nvram_fetch, nvram_store;
+static char nvram_buf[NVRW_CNT];        /* assume this is in the first 4GB */
+static DEFINE_SPINLOCK(nvram_lock);
+
+
+static ssize_t pSeries_nvram_read(char *buf, size_t count, loff_t *index)
+{
+        unsigned int i;
+        unsigned long len;
+        int done;
+        unsigned long flags;
+        char *p = buf;
+
+
+        if (nvram_size == 0 || nvram_fetch == RTAS_UNKNOWN_SERVICE)
+                return -ENODEV;
+
+        if (*index >= nvram_size)
+                return 0;
+
+        i = *index;
+        if (i + count > nvram_size)
+                count = nvram_size - i;
+
+        spin_lock_irqsave(&nvram_lock, flags);
+
+        for (; count != 0; count -= len) {
+                len = count;
+                if (len > NVRW_CNT)
+                        len = NVRW_CNT;
+                
+                if ((rtas_call(nvram_fetch, 3, 2, &done, i, __pa(nvram_buf),
+                               len) != 0) || len != done) {
+                        spin_unlock_irqrestore(&nvram_lock, flags);
+                        return -EIO;
+                }
+                
+                memcpy(p, nvram_buf, len);
+
+                p += len;
+                i += len;
+        }
+
+        spin_unlock_irqrestore(&nvram_lock, flags);
+        
+        *index = i;
+        return p - buf;
+}
+
+static ssize_t pSeries_nvram_write(char *buf, size_t count, loff_t *index)
+{
+        unsigned int i;
+        unsigned long len;
+        int done;
+        unsigned long flags;
+        const char *p = buf;
+
+        if (nvram_size == 0 || nvram_store == RTAS_UNKNOWN_SERVICE)
+                return -ENODEV;
+
+        if (*index >= nvram_size)
+                return 0;
+
+        i = *index;
+        if (i + count > nvram_size)
+                count = nvram_size - i;
+
+        spin_lock_irqsave(&nvram_lock, flags);
+
+        for (; count != 0; count -= len) {
+                len = count;
+                if (len > NVRW_CNT)
+                        len = NVRW_CNT;
+
+                memcpy(nvram_buf, p, len);
+
+                if ((rtas_call(nvram_store, 3, 2, &done, i, __pa(nvram_buf),
+                               len) != 0) || len != done) {
+                        spin_unlock_irqrestore(&nvram_lock, flags);
+                        return -EIO;
+                }
+                
+                p += len;
+                i += len;
+        }
+        spin_unlock_irqrestore(&nvram_lock, flags);
+        
+        *index = i;
+        return p - buf;
+}
+
+static ssize_t pSeries_nvram_get_size(void)
+{
+        return nvram_size ? nvram_size : -ENODEV;
+}
+
+int __init pSeries_nvram_init(void)
+{
+        struct device_node *nvram;
+        unsigned int *nbytes_p, proplen;
+
+        nvram = of_find_node_by_type(NULL, "nvram");
+        if (nvram == NULL)
+                return -ENODEV;
+
+        nbytes_p = (unsigned int *)get_property(nvram, "#bytes", &proplen);
+        if (nbytes_p == NULL || proplen != sizeof(unsigned int))
+                return -EIO;
+
+        nvram_size = *nbytes_p;
+
+        nvram_fetch = rtas_token("nvram-fetch");
+        nvram_store = rtas_token("nvram-store");
+        printk(KERN_INFO "PPC64 nvram contains %d bytes\n", nvram_size);
+        of_node_put(nvram);
+
+        ppc_md.nvram_read       = pSeries_nvram_read;
+        ppc_md.nvram_write      = pSeries_nvram_write;
+        ppc_md.nvram_size       = pSeries_nvram_get_size;
+
+        return 0;
+}