Hack to load PS3 legacy kernels (2.6.16 and fc7 installer) with the 2.6.23
mainline linux kernel.

---
 kexec/arch/ppc64/fs2dt.c           |   47 +++++++++++++++++++++++++++++++++++++
 kexec/arch/ppc64/kexec-elf-ppc64.c |   44 ++++++++++++++++++++++++++++++++++
 kexec/arch/ppc64/kexec-ppc64.c     |    5 +++
 kexec/arch/ppc64/kexec-ppc64.h     |    2 +
 4 files changed, 98 insertions(+)

--- a/kexec/arch/ppc64/fs2dt.c
+++ b/kexec/arch/ppc64/fs2dt.c
@@ -262,6 +262,33 @@ static void putprops(char *fn, struct di
 			die("unrecoverable error: could not read \"%s\": %s\n",
 			    pathname, strerror(errno));
 
+		/* ps3 legacy - Add 'PS3PF' to compatible */
+
+		if (ps3_legacy && !strcmp(dp->d_name, "compatible")) {
+			static const char s[] = "PS3PF";
+			char *const tmp = (char *)dt + len;
+
+			memcpy(tmp, s, sizeof(s));
+			len += sizeof(s);
+			*dt_len = len;
+
+			fprintf(stdout, "ps3 legacy: Changed dt entry "
+				"/compatible: <%s> -> <%s %s>\n",
+				(char *)dt, (char *)dt, tmp);
+		}
+
+		/* ps3 legacy - force memory.reg to 224 MiB */
+
+		if (ps3_legacy && !strcmp(dp->d_name, "reg") && len == 16) {
+			uint64_t tmp = *((uint64_t *)dt + 1);
+
+			*((uint64_t *)dt + 1) = 0xe000000ULL;
+			fprintf(stdout, "ps3 legacy: Changed dt entry "
+				"/memory/reg: <%llx> -> <%llx>\n",
+				(unsigned long long)tmp,
+				*((unsigned long long *)dt + 1));
+		}
+
 		checkprop(fn, dt, len);
 
 		dt += (len + 3)/4;
@@ -360,6 +387,26 @@ static void putnode(void)
 		reserve(initrd_base, initrd_size);
 	}
 
+	/* ps3 legacy - add entry linux,platform <801> */
+
+	if (ps3_legacy && !strcmp(basename,"/chosen/")) {
+		int len = 4;
+		static const uint32_t data = 0x801UL;
+
+		*dt++ = 3;
+		*dt++ = len;
+		*dt++ = propnum("linux,platform");
+
+		if ((len >= 8) && ((unsigned long)dt & 0x4))
+			dt++;
+
+		memcpy(dt,&data,len);
+		dt += (len + 3)/4;
+
+		fprintf(stdout, "ps3 legacy: Added dt entry "
+			"/chosen/linux,platform = <801>\n");
+	}
+
 	/* Add cmdline to the second kernel.  Check to see if the new
 	 * cmdline has a root=.  If not, use the old root= cmdline.  */
 	if (!strcmp(basename,"/chosen/")) {
--- a/kexec/arch/ppc64/kexec-elf-ppc64.c
+++ b/kexec/arch/ppc64/kexec-elf-ppc64.c
@@ -45,6 +45,7 @@
 uint64_t initrd_base, initrd_size;
 unsigned char reuse_initrd = 0;
 const char *ramdisk;
+int ps3_legacy = -1; /* default to probe */
 
 int create_flatten_tree(struct kexec_info *, unsigned char **, unsigned long *,
 			char *);
@@ -76,6 +77,33 @@ void arch_reuse_initrd(void)
 	reuse_initrd = 1;
 }
 
+/**
+ * ps3_legacy_probe - Probe kernel version.
+ */
+
+static int ps3_legacy_probe(const char *p, off_t len)
+{
+	static const char d1[] = "linux,platform";    /* legacy 2.6.16 */
+	static const char d2[] = "2.6.21-1.3194.fc7"; /* fedora 7 installer */
+	const char *const end = p + len - sizeof(d2);
+
+	while(p < end) {
+		if (p[0] == d1[0] && !memcmp(p, d1, sizeof(d1) - 1)) {
+			fprintf(stdout, "ps3 legacy: Legacy kernel found: "
+				"'%s'\n", d1);
+			break;
+		}
+		if (p[0] == d2[0] && !memcmp(p, d2, sizeof(d2) - 1)) {
+			fprintf(stdout, "ps3 legacy: Legacy kernel found: "
+				"'%s'\n", d2);
+			break;
+		}
+		p++;
+	}
+
+	return (p != end);
+}
+
 int elf_ppc64_load(int argc, char **argv, const char *buf, off_t len,
 			struct kexec_info *info)
 {
@@ -102,6 +130,8 @@ int elf_ppc64_load(int argc, char **argv
 #define OPT_RAMDISK     (OPT_ARCH_MAX+1)
 #define OPT_DEVICETREEBLOB     (OPT_ARCH_MAX+2)
 #define OPT_ARGS_IGNORE		(OPT_ARCH_MAX+3)
+#define OPT_PS3_LEGACY (OPT_ARCH_MAX+4)
+#define OPT_PS3_LEGACY_NO (OPT_ARCH_MAX+5)
 
 	static const struct option options[] = {
 		KEXEC_ARCH_OPTIONS
@@ -111,6 +141,8 @@ int elf_ppc64_load(int argc, char **argv
 		{ "initrd",             1, NULL, OPT_RAMDISK },
 		{ "devicetreeblob",     1, NULL, OPT_DEVICETREEBLOB },
 		{ "args-linux",		0, NULL, OPT_ARGS_IGNORE },
+		{ "ps3-legacy",         0, NULL, OPT_PS3_LEGACY },
+		{ "ps3-no-legacy",      0, NULL, OPT_PS3_LEGACY_NO },
 		{ 0,                    0, NULL, 0 },
 	};
 
@@ -146,9 +178,18 @@ int elf_ppc64_load(int argc, char **argv
 			break;
 		case OPT_ARGS_IGNORE:
 			break;
+		case OPT_PS3_LEGACY:
+			ps3_legacy = 1;
+			break;
+		case OPT_PS3_LEGACY_NO:
+			ps3_legacy = 0;
+			break;
 		}
 	}
 
+	if (ps3_legacy == -1)
+		ps3_legacy = ps3_legacy_probe(buf, len);
+
 	cmdline_len = 0;
 	if (cmdline)
 		cmdline_len = strlen(cmdline) + 1;
@@ -158,6 +199,9 @@ int elf_ppc64_load(int argc, char **argv
 	if (ramdisk && reuse_initrd)
 		die("Can't specify --ramdisk or --initrd with --reuseinitrd\n");
 
+	if (ps3_legacy && devicetreeblob)
+		die("Can't specify --devicetreeblob with --ps3-legacy\n");
+
 	setup_memory_ranges(info->kexec_flags);
 
 	/* Need to append some command line parameters internally in case of
--- a/kexec/arch/ppc64/kexec-ppc64.c
+++ b/kexec/arch/ppc64/kexec-ppc64.c
@@ -650,6 +650,11 @@ void arch_usage(void)
 	fprintf(stderr, "     --initrd=<filename> same as --ramdisk.\n");
 	fprintf(stderr, "     --devicetreeblob=<filename> Specify device tree blob file.\n");
 	fprintf(stderr, "     --elf64-core-headers Prepare core headers in ELF64 format\n");
+	fprintf(stderr, "     --ps3-legacy    Make fixups needed to boot PS3 legacy kernels.\n");
+	fprintf(stderr, "                     The default is to probe the kernel type.\n");
+	fprintf(stderr, "     --ps3-no-legacy Do not make fixups needed to boot PS3 legacy\n");
+	fprintf(stderr, "                     kernels. The default is to probe the kernel\n");
+	fprintf(stderr, "                     type.\n");
 }
 
 struct arch_options_t arch_options = {
--- a/kexec/arch/ppc64/kexec-ppc64.h
+++ b/kexec/arch/ppc64/kexec-ppc64.h
@@ -41,4 +41,6 @@ typedef struct mem_rgns {
 
 extern mem_rgns_t usablemem_rgns;
 
+extern int ps3_legacy;
+
 #endif /* KEXEC_PPC64_H */