Merge tag 'v2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

[mv-sheeva.git] / arch / x86 / platform / olpc / olpc_dt.c

diff --git a/arch/x86/platform/olpc/olpc_dt.c b/arch/x86/platform/olpc/olpc_dt.c
new file mode 100644 (file)
index 0000000..044bda5
--- /dev/null
+++ b/arch/x86/platform/olpc/olpc_dt.c
@@ -0,0 +1,182 @@
+/*
+ * OLPC-specific OFW device tree support code.
+ *
+ * Paul Mackerras      August 1996.
+ * Copyright (C) 1996-2005 Paul Mackerras.
+ *
+ *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
+ *    {engebret|bergner}@us.ibm.com
+ *
+ *  Adapted for sparc by David S. Miller davem@davemloft.net
+ *  Adapted for x86/OLPC by Andres Salomon <dilinger@queued.net>
+ *
+ *      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/kernel.h>
+#include <linux/bootmem.h>
+#include <linux/of.h>
+#include <linux/of_pdt.h>
+#include <asm/olpc_ofw.h>
+
+static phandle __init olpc_dt_getsibling(phandle node)
+{
+       const void *args[] = { (void *)node };
+       void *res[] = { &node };
+
+       if ((s32)node == -1)
+               return 0;
+
+       if (olpc_ofw("peer", args, res) || (s32)node == -1)
+               return 0;
+
+       return node;
+}
+
+static phandle __init olpc_dt_getchild(phandle node)
+{
+       const void *args[] = { (void *)node };
+       void *res[] = { &node };
+
+       if ((s32)node == -1)
+               return 0;
+
+       if (olpc_ofw("child", args, res) || (s32)node == -1) {
+               pr_err("PROM: %s: fetching child failed!\n", __func__);
+               return 0;
+       }
+
+       return node;
+}
+
+static int __init olpc_dt_getproplen(phandle node, const char *prop)
+{
+       const void *args[] = { (void *)node, prop };
+       int len;
+       void *res[] = { &len };
+
+       if ((s32)node == -1)
+               return -1;
+
+       if (olpc_ofw("getproplen", args, res)) {
+               pr_err("PROM: %s: getproplen failed!\n", __func__);
+               return -1;
+       }
+
+       return len;
+}
+
+static int __init olpc_dt_getproperty(phandle node, const char *prop,
+               char *buf, int bufsize)
+{
+       int plen;
+
+       plen = olpc_dt_getproplen(node, prop);
+       if (plen > bufsize || plen < 1) {
+               return -1;
+       } else {
+               const void *args[] = { (void *)node, prop, buf, (void *)plen };
+               void *res[] = { &plen };
+
+               if (olpc_ofw("getprop", args, res)) {
+                       pr_err("PROM: %s: getprop failed!\n", __func__);
+                       return -1;
+               }
+       }
+
+       return plen;
+}
+
+static int __init olpc_dt_nextprop(phandle node, char *prev, char *buf)
+{
+       const void *args[] = { (void *)node, prev, buf };
+       int success;
+       void *res[] = { &success };
+
+       buf[0] = '\0';
+
+       if ((s32)node == -1)
+               return -1;
+
+       if (olpc_ofw("nextprop", args, res) || success != 1)
+               return -1;
+
+       return 0;
+}
+
+static int __init olpc_dt_pkg2path(phandle node, char *buf,
+               const int buflen, int *len)
+{
+       const void *args[] = { (void *)node, buf, (void *)buflen };
+       void *res[] = { len };
+
+       if ((s32)node == -1)
+               return -1;
+
+       if (olpc_ofw("package-to-path", args, res) || *len < 1)
+               return -1;
+
+       return 0;
+}
+
+static unsigned int prom_early_allocated __initdata;
+
+void * __init prom_early_alloc(unsigned long size)
+{
+       static u8 *mem;
+       static size_t free_mem;
+       void *res;
+
+       if (free_mem < size) {
+               const size_t chunk_size = max(PAGE_SIZE, size);
+
+               /*
+                * To mimimize the number of allocations, grab at least
+                * PAGE_SIZE of memory (that's an arbitrary choice that's
+                * fast enough on the platforms we care about while minimizing
+                * wasted bootmem) and hand off chunks of it to callers.
+                */
+               res = alloc_bootmem(chunk_size);
+               BUG_ON(!res);
+               prom_early_allocated += chunk_size;
+               memset(res, 0, chunk_size);
+               free_mem = chunk_size;
+               mem = res;
+       }
+
+       /* allocate from the local cache */
+       free_mem -= size;
+       res = mem;
+       mem += size;
+       return res;
+}
+
+static struct of_pdt_ops prom_olpc_ops __initdata = {
+       .nextprop = olpc_dt_nextprop,
+       .getproplen = olpc_dt_getproplen,
+       .getproperty = olpc_dt_getproperty,
+       .getchild = olpc_dt_getchild,
+       .getsibling = olpc_dt_getsibling,
+       .pkg2path = olpc_dt_pkg2path,
+};
+
+void __init olpc_dt_build_devicetree(void)
+{
+       phandle root;
+
+       if (!olpc_ofw_is_installed())
+               return;
+
+       root = olpc_dt_getsibling(0);
+       if (!root) {
+               pr_err("PROM: unable to get root node from OFW!\n");
+               return;
+       }
+       of_pdt_build_devicetree(root, &prom_olpc_ops);
+
+       pr_info("PROM DT: Built device tree with %u bytes of memory.\n",
+                       prom_early_allocated);
+}