Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / arch / powerpc / sysdev / mmio_nvram.c

diff --git a/kernel/arch/powerpc/sysdev/mmio_nvram.c b/kernel/arch/powerpc/sysdev/mmio_nvram.c
new file mode 100644 (file)
index 0000000..69f5814
--- /dev/null
+++ b/kernel/arch/powerpc/sysdev/mmio_nvram.c
@@ -0,0 +1,158 @@
+/*
+ * 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 DEFINE_SPINLOCK(mmio_nvram_lock);
+
+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 unsigned char mmio_nvram_read_val(int addr)
+{
+       unsigned long flags;
+       unsigned char val;
+
+       if (addr >= mmio_nvram_len)
+               return 0xff;
+
+       spin_lock_irqsave(&mmio_nvram_lock, flags);
+
+       val = ioread8(mmio_nvram_start + addr);
+
+       spin_unlock_irqrestore(&mmio_nvram_lock, flags);
+
+       return val;
+}
+
+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;
+}
+
+void mmio_nvram_write_val(int addr, unsigned char val)
+{
+       unsigned long flags;
+
+       if (addr < mmio_nvram_len) {
+               spin_lock_irqsave(&mmio_nvram_lock, flags);
+
+               iowrite8(val, mmio_nvram_start + addr);
+
+               spin_unlock_irqrestore(&mmio_nvram_lock, flags);
+       }
+}
+
+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 nvram_addr;
+       struct resource r;
+       int ret;
+
+       nvram_node = of_find_node_by_type(NULL, "nvram");
+       if (!nvram_node)
+               nvram_node = of_find_compatible_node(NULL, NULL, "nvram");
+       if (!nvram_node) {
+               printk(KERN_WARNING "nvram: no node found in device-tree\n");
+               return -ENODEV;
+       }
+
+       ret = of_address_to_resource(nvram_node, 0, &r);
+       if (ret) {
+               printk(KERN_WARNING "nvram: failed to get address (err %d)\n",
+                      ret);
+               goto out;
+       }
+       nvram_addr = r.start;
+       mmio_nvram_len = resource_size(&r);
+       if ( (!mmio_nvram_len) || (!nvram_addr) ) {
+               printk(KERN_WARNING "nvram: address or length is 0\n");
+               ret = -EIO;
+               goto out;
+       }
+
+       mmio_nvram_start = ioremap(nvram_addr, mmio_nvram_len);
+       if (!mmio_nvram_start) {
+               printk(KERN_WARNING "nvram: failed to ioremap\n");
+               ret = -ENOMEM;
+               goto out;
+       }
+
+       printk(KERN_INFO "mmio NVRAM, %luk at 0x%lx mapped to %p\n",
+              mmio_nvram_len >> 10, nvram_addr, mmio_nvram_start);
+
+       ppc_md.nvram_read_val   = mmio_nvram_read_val;
+       ppc_md.nvram_write_val  = mmio_nvram_write_val;
+       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;
+}