Some platforms have a boot agent that can create or modify properties in
the device-tree and load images into memory. Provide a helper to set
loader_info used by prep_initrd().
Signed-off-by: Milton Miller <[EMAIL PROTECTED]>
Acked-by: David Gibson <[EMAIL PROTECTED]>
---
re 12168
rediffed types.h, offset in ops.h
Index: kernel/arch/powerpc/boot/ops.h
===================================================================
--- kernel.orig/arch/powerpc/boot/ops.h 2007-09-17 22:12:47.000000000 -0500
+++ kernel/arch/powerpc/boot/ops.h 2007-09-17 22:12:51.000000000 -0500
@@ -163,6 +163,7 @@ void dt_fixup_clock(const char *path, u3
void __dt_fixup_mac_addresses(u32 startindex, ...);
#define dt_fixup_mac_addresses(...) \
__dt_fixup_mac_addresses(0, __VA_ARGS__, NULL)
+void dt_find_initrd(void);
static inline void *find_node_by_linuxphandle(const u32 linuxphandle)
Index: kernel/arch/powerpc/boot/types.h
===================================================================
--- kernel.orig/arch/powerpc/boot/types.h 2007-09-17 22:12:47.000000000
-0500
+++ kernel/arch/powerpc/boot/types.h 2007-09-17 22:12:51.000000000 -0500
@@ -12,6 +12,8 @@ typedef short s16;
typedef int s32;
typedef long long s64;
+#define UINT_MAX 0xFFFFFFFF
+
#define min(x,y) ({ \
typeof(x) _x = (x); \
typeof(y) _y = (y); \
Index: kernel/arch/powerpc/boot/devtree.c
===================================================================
--- kernel.orig/arch/powerpc/boot/devtree.c 2007-09-17 22:12:47.000000000
-0500
+++ kernel/arch/powerpc/boot/devtree.c 2007-09-17 22:12:51.000000000 -0500
@@ -1,6 +1,7 @@
/*
* devtree.c - convenience functions for device tree manipulation
* Copyright 2007 David Gibson, IBM Corporation.
+ * Copyright 2007 Milton Miller, IBM Corporation.
* Copyright (c) 2007 Freescale Semiconductor, Inc.
*
* Authors: David Gibson <[EMAIL PROTECTED]>
@@ -333,3 +334,68 @@ int dt_is_compatible(void *node, const c
return 0;
}
+
+/**
+ * dt_find_initrd - set loader initrd location based on existing properties
+ *
+ * finds the linux,initrd-start and linux,initrd-end properties in
+ * the /chosen node and sets the loader initrd fields accordingly.
+ *
+ * Use this if your loader sets the properties to allow other code to
+ * relocate the tree and/or cause r3 and r4 to be set on true OF
+ * platforms.
+ */
+void dt_find_initrd(void)
+{
+ int rc;
+ unsigned long long initrd_start, initrd_end;
+ void *devp;
+ static const char start_prop[] = "linux,initrd-start";
+ static const char end_prop[] = "linux,initrd-end";
+
+ devp = finddevice("/chosen");
+ if (! devp) {
+ return;
+ }
+
+ rc = getprop(devp, start_prop, &initrd_start, sizeof(initrd_start));
+ if (rc < 0)
+ return; /* not found */
+ /* The properties had to be 8 bytes until 2.6.22 */
+ if (rc == sizeof(unsigned long)) {
+ unsigned long tmp;
+ memcpy(&tmp, &initrd_start, rc);
+ initrd_start = tmp;
+ } else if (rc != sizeof(initrd_start)) { /* now they can be 4 */
+ printf("unexpected length of %s in /chosen!\n\r", start_prop);
+ return;
+ }
+
+ rc = getprop(devp, end_prop, &initrd_end, sizeof(initrd_end));
+ if (rc < 0) {
+ printf("chosen has %s but no %s!\n\r", start_prop, end_prop);
+ return;
+ }
+ if (rc == sizeof(unsigned long)) {
+ unsigned long tmp;
+ memcpy(&tmp, &initrd_end, rc);
+ initrd_end = tmp;
+ } else if (rc != sizeof(initrd_end)) {
+ printf("unexpected length of %s in /chosen!\n\r", end_prop);
+ return;
+ }
+
+ /* Check for presence, ignore if (partially) loaded above 32 bits */
+ if (initrd_start == initrd_end) {
+ printf("ignoring empty device-tree supplied initrd\n");
+ } else if (initrd_start > initrd_end) {
+ printf("ignoring device-tree supplied initrd: start 0x%llx"
+ " > end 0x%llx \n", initrd_start, initrd_end);
+ } else if (initrd_end > UINT_MAX) {
+ printf("ignoring device-tree supplied initrd:"
+ " end 0x%llx > 32 bits\n", initrd_end);
+ } else {
+ loader_info.initrd_addr = initrd_start;
+ loader_info.initrd_size = initrd_end - initrd_start;
+ }
+}
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