4 * Copyright 2011 IBM Corp.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
14 #include <linux/kernel.h>
15 #include <linux/init.h>
19 #include <asm/nvram.h>
20 #include <asm/machdep.h>
22 static unsigned int nvram_size;
24 static ssize_t opal_nvram_size(void)
29 static ssize_t opal_nvram_read(char *buf, size_t count, loff_t *index)
34 if (*index >= nvram_size)
37 if ((off + count) > nvram_size)
38 count = nvram_size - off;
39 rc = opal_read_nvram(__pa(buf), count, off);
40 if (rc != OPAL_SUCCESS)
46 static ssize_t opal_nvram_write(char *buf, size_t count, loff_t *index)
51 if (*index >= nvram_size)
54 if ((off + count) > nvram_size)
55 count = nvram_size - off;
57 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
58 rc = opal_write_nvram(__pa(buf), count, off);
59 if (rc == OPAL_BUSY_EVENT)
60 opal_poll_events(NULL);
66 static int __init opal_nvram_init_log_partitions(void)
68 /* Scan nvram for partitions */
69 nvram_scan_partitions();
70 nvram_init_oops_partition(0);
73 machine_arch_initcall(powernv, opal_nvram_init_log_partitions);
75 void __init opal_nvram_init(void)
77 struct device_node *np;
78 const __be32 *nbytes_p;
80 np = of_find_compatible_node(NULL, NULL, "ibm,opal-nvram");
84 nbytes_p = of_get_property(np, "#bytes", NULL);
89 nvram_size = be32_to_cpup(nbytes_p);
91 pr_info("OPAL nvram setup, %u bytes\n", nvram_size);
94 ppc_md.nvram_read = opal_nvram_read;
95 ppc_md.nvram_write = opal_nvram_write;
96 ppc_md.nvram_size = opal_nvram_size;