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diff --git a/target/linux/olpc/files/arch/i386/kernel/ofw.c b/target/linux/olpc/files/arch/i386/kernel/ofw.c
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+++ b/target/linux/olpc/files/arch/i386/kernel/ofw.c
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+/*
+ * ofw.c - Open Firmware client interface for 32-bit systems.
+ * This code is intended to be portable to any 32-bit Open Firmware
+ * implementation with a standard client interface that can be
+ * called when Linux is running.
+ *
+ * Copyright (C) 2007 Mitch Bradley <wmb@firmworks.com>
+ * Copyright (C) 2007 Andres Salomon <dilinger@debian.org>
+ */
+
+#include <stdarg.h>
+#include <linux/spinlock.h>
+#include <linux/module.h>
+#include <asm/ofw.h>
+
+
+int (*call_firmware)(int *);
+
+static DEFINE_SPINLOCK(prom_lock);
+
+#define MAXARGS 20
+
+/*
+ * The return value from ofw() in all cases is 0 if the attempt to call the
+ * function succeeded, <0 otherwise. That return value is from the
+ * gateway function only. Any results from the called function are returned
+ * via output argument pointers.
+ *
+ * Here are call templates for all the standard OFW client services:
+ *
+ * ofw("test", 1, 1, namestr, &missing);
+ * ofw("peer", 1, 1, phandle, &sibling_phandle);
+ * ofw("child", 1, 1, phandle, &child_phandle);
+ * ofw("parent", 1, 1, phandle, &parent_phandle);
+ * ofw("instance_to_package", 1, 1, ihandle, &phandle);
+ * ofw("getproplen", 2, 1, phandle, namestr, &proplen);
+ * ofw("getprop", 4, 1, phandle, namestr, bufaddr, buflen, &size);
+ * ofw("nextprop", 3, 1, phandle, previousstr, bufaddr, &flag);
+ * ofw("setprop", 4, 1, phandle, namestr, bufaddr, len, &size);
+ * ofw("canon", 3, 1, devspecstr, bufaddr, buflen, &length);
+ * ofw("finddevice", 1, 1, devspecstr, &phandle);
+ * ofw("instance-to-path", 3, 1, ihandle, bufaddr, buflen, &length);
+ * ofw("package-to-path", 3, 1, phandle, bufaddr, buflen, &length);
+ * ofw("call_method", numin, numout, in0, in1, ..., &out0, &out1, ...);
+ * ofw("open", 1, 1, devspecstr, &ihandle);
+ * ofw("close", 1, 0, ihandle);
+ * ofw("read", 3, 1, ihandle, addr, len, &actual);
+ * ofw("write", 3, 1, ihandle, addr, len, &actual);
+ * ofw("seek", 3, 1, ihandle, pos_hi, pos_lo, &status);
+ * ofw("claim", 3, 1, virtaddr, size, align, &baseaddr);
+ * ofw("release", 2, 0, virtaddr, size);
+ * ofw("boot", 1, 0, bootspecstr);
+ * ofw("enter", 0, 0);
+ * ofw("exit", 0, 0);
+ * ofw("chain", 5, 0, virtaddr, size, entryaddr, argsaddr, len);
+ * ofw("interpret", numin+1, numout+1, cmdstr, in0, ..., &catchres, &out0, ...);
+ * ofw("set-callback", 1, 1, newfuncaddr, &oldfuncaddr);
+ * ofw("set-symbol-lookup", 2, 0, symtovaladdr, valtosymaddr);
+ * ofw("milliseconds", 0, 1, &ms);
+ */
+
+int ofw(char *name, int numargs, int numres, ...)
+{
+ va_list ap;
+ int argarray[MAXARGS+3];
+ int argnum = 3;
+ int retval;
+ int *intp;
+ unsigned long flags;
+
+ if (!call_firmware)
+ return -1;
+ if ((numargs + numres) > MAXARGS)
+ return -1; /* spit out an error? */
+
+ argarray[0] = (int) name;
+ argarray[1] = numargs;
+ argarray[2] = numres;
+
+ va_start(ap, numres);
+ while (numargs) {
+ argarray[argnum++] = va_arg(ap, int);
+ numargs--;
+ }
+
+ spin_lock_irqsave(&prom_lock, flags);
+ retval = call_firmware(argarray);
+ spin_unlock_irqrestore(&prom_lock, flags);
+
+ if (retval == 0) {
+ while (numres) {
+ intp = va_arg(ap, int *);
+ *intp = argarray[argnum++];
+ numres--;
+ }
+ }
+ va_end(ap);
+ return retval;
+}
+EXPORT_SYMBOL(ofw);