diff options
author | Arnd Bergmann <arndb@de.ibm.com> | 2005-10-31 20:08:40 -0500 |
---|---|---|
committer | Paul Mackerras <paulus@samba.org> | 2005-11-01 21:03:04 +1100 |
commit | edf03c1ee84e5095e8f4a4b8ad6e0784118cb176 (patch) | |
tree | 2b86e57df3cfd2767fffb55ccf4b04e4d28c5c75 /arch/powerpc/sysdev/mmio_nvram.c | |
parent | e9add2eeb182e2bf1863c548f7a8173c45b4b92f (diff) |
[PATCH] powerpc: move mmio_nvram.c over to arch/powerpc
The nvram code formally known as bpa_nvram.c is rather
generic really, so it is quite likely to be useful to
future boards not based on cell.
This patch puts it into arch/powerpc/sysdev.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/sysdev/mmio_nvram.c')
-rw-r--r-- | arch/powerpc/sysdev/mmio_nvram.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/mmio_nvram.c b/arch/powerpc/sysdev/mmio_nvram.c new file mode 100644 index 00000000000..74e0d31a355 --- /dev/null +++ b/arch/powerpc/sysdev/mmio_nvram.c @@ -0,0 +1,118 @@ +/* + * memory mapped NVRAM + * + * (C) Copyright IBM Corp. 2005 + * + * Authors : Utz Bacher <utz.bacher@de.ibm.com> + * + * 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, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <linux/fs.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/spinlock.h> +#include <linux/types.h> + +#include <asm/machdep.h> +#include <asm/nvram.h> +#include <asm/prom.h> + +static void __iomem *mmio_nvram_start; +static long mmio_nvram_len; +static spinlock_t mmio_nvram_lock = SPIN_LOCK_UNLOCKED; + +static ssize_t mmio_nvram_read(char *buf, size_t count, loff_t *index) +{ + unsigned long flags; + + if (*index >= mmio_nvram_len) + return 0; + if (*index + count > mmio_nvram_len) + count = mmio_nvram_len - *index; + + spin_lock_irqsave(&mmio_nvram_lock, flags); + + memcpy_fromio(buf, mmio_nvram_start + *index, count); + + spin_unlock_irqrestore(&mmio_nvram_lock, flags); + + *index += count; + return count; +} + +static ssize_t mmio_nvram_write(char *buf, size_t count, loff_t *index) +{ + unsigned long flags; + + if (*index >= mmio_nvram_len) + return 0; + if (*index + count > mmio_nvram_len) + count = mmio_nvram_len - *index; + + spin_lock_irqsave(&mmio_nvram_lock, flags); + + memcpy_toio(mmio_nvram_start + *index, buf, count); + + spin_unlock_irqrestore(&mmio_nvram_lock, flags); + + *index += count; + return count; +} + +static ssize_t mmio_nvram_get_size(void) +{ + return mmio_nvram_len; +} + +int __init mmio_nvram_init(void) +{ + struct device_node *nvram_node; + unsigned long *buffer; + int proplen; + unsigned long nvram_addr; + int ret; + + ret = -ENODEV; + nvram_node = of_find_node_by_type(NULL, "nvram"); + if (!nvram_node) + goto out; + + ret = -EIO; + buffer = (unsigned long *)get_property(nvram_node, "reg", &proplen); + if (proplen != 2*sizeof(unsigned long)) + goto out; + + ret = -ENODEV; + nvram_addr = buffer[0]; + mmio_nvram_len = buffer[1]; + if ( (!mmio_nvram_len) || (!nvram_addr) ) + goto out; + + mmio_nvram_start = ioremap(nvram_addr, mmio_nvram_len); + if (!mmio_nvram_start) + goto out; + + printk(KERN_INFO "mmio NVRAM, %luk mapped to %p\n", + mmio_nvram_len >> 10, mmio_nvram_start); + + ppc_md.nvram_read = mmio_nvram_read; + ppc_md.nvram_write = mmio_nvram_write; + ppc_md.nvram_size = mmio_nvram_get_size; + +out: + of_node_put(nvram_node); + return ret; +} |