powerpc: Move ppc64 boot wrapper code over to arch/powerpc

This also extends the code to handle 32-bit ELF vmlinux files as well
as 64-bit ones.  This is sufficient for booting on new-world 32-bit
powermacs (i.e. all recent machines).

Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 321 insertions, 0 deletions

diff --git a/arch/powerpc/boot/main.c b/arch/powerpc/boot/main.c
new file mode 100644
index 000000000000..64ec93116fa6
--- /dev/null
+++ b/arch/powerpc/boot/main.c
@@ -0,0 +1,321 @@
+/*
+ * Copyright (C) Paul Mackerras 1997.
+ *
+ * Updates for PPC64 by Todd Inglett, Dave Engebretsen & Peter Bergner.
+ *
+ * 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 <stdarg.h>
+#include <stddef.h>
+#include "elf.h"
+#include "page.h"
+#include "string.h"
+#include "stdio.h"
+#include "prom.h"
+#include "zlib.h"
+
+extern void flush_cache(void *, unsigned long);
+
+
+/* Value picked to match that used by yaboot */
+#define PROG_START	0x01400000
+#define RAM_END		(512<<20) // Fixme: use OF */
+#define	ONE_MB		0x100000
+
+extern char _start[];
+extern char __bss_start[];
+extern char _end[];
+extern char _vmlinux_start[];
+extern char _vmlinux_end[];
+extern char _initrd_start[];
+extern char _initrd_end[];
+
+struct addr_range {
+	unsigned long addr;
+	unsigned long size;
+	unsigned long memsize;
+};
+static struct addr_range vmlinux;
+static struct addr_range vmlinuz;
+static struct addr_range initrd;
+
+static unsigned long elfoffset;
+
+static char scratch[46912];	/* scratch space for gunzip, from zlib_inflate_workspacesize() */
+static char elfheader[256];
+
+
+typedef void (*kernel_entry_t)( unsigned long,
+                                unsigned long,
+                                void *,
+				void *);
+
+
+#undef DEBUG
+
+static unsigned long claim_base;
+
+#define HEAD_CRC	2
+#define EXTRA_FIELD	4
+#define ORIG_NAME	8
+#define COMMENT		0x10
+#define RESERVED	0xe0
+
+static void gunzip(void *dst, int dstlen, unsigned char *src, int *lenp)
+{
+	z_stream s;
+	int r, i, flags;
+
+	/* skip header */
+	i = 10;
+	flags = src[3];
+	if (src[2] != Z_DEFLATED || (flags & RESERVED) != 0) {
+		printf("bad gzipped data\n\r");
+		exit();
+	}
+	if ((flags & EXTRA_FIELD) != 0)
+		i = 12 + src[10] + (src[11] << 8);
+	if ((flags & ORIG_NAME) != 0)
+		while (src[i++] != 0)
+			;
+	if ((flags & COMMENT) != 0)
+		while (src[i++] != 0)
+			;
+	if ((flags & HEAD_CRC) != 0)
+		i += 2;
+	if (i >= *lenp) {
+		printf("gunzip: ran out of data in header\n\r");
+		exit();
+	}
+
+	if (zlib_inflate_workspacesize() > sizeof(scratch)) {
+		printf("gunzip needs more mem\n");
+		exit();
+	}
+	memset(&s, 0, sizeof(s));
+	s.workspace = scratch;
+	r = zlib_inflateInit2(&s, -MAX_WBITS);
+	if (r != Z_OK) {
+		printf("inflateInit2 returned %d\n\r", r);
+		exit();
+	}
+	s.next_in = src + i;
+	s.avail_in = *lenp - i;
+	s.next_out = dst;
+	s.avail_out = dstlen;
+	r = zlib_inflate(&s, Z_FULL_FLUSH);
+	if (r != Z_OK && r != Z_STREAM_END) {
+		printf("inflate returned %d msg: %s\n\r", r, s.msg);
+		exit();
+	}
+	*lenp = s.next_out - (unsigned char *) dst;
+	zlib_inflateEnd(&s);
+}
+
+static unsigned long try_claim(unsigned long size)
+{
+	unsigned long addr = 0;
+
+	for(; claim_base < RAM_END; claim_base += ONE_MB) {
+#ifdef DEBUG
+		printf("    trying: 0x%08lx\n\r", claim_base);
+#endif
+		addr = (unsigned long)claim(claim_base, size, 0);
+		if ((void *)addr != (void *)-1)
+			break;
+	}
+	if (addr == 0)
+		return 0;
+	claim_base = PAGE_ALIGN(claim_base + size);
+	return addr;
+}
+
+static int is_elf64(void *hdr)
+{
+	Elf64_Ehdr *elf64 = hdr;
+	Elf64_Phdr *elf64ph;
+	unsigned int i;
+
+	if (!(elf64->e_ident[EI_MAG0]  == ELFMAG0	&&
+	      elf64->e_ident[EI_MAG1]  == ELFMAG1	&&
+	      elf64->e_ident[EI_MAG2]  == ELFMAG2	&&
+	      elf64->e_ident[EI_MAG3]  == ELFMAG3	&&
+	      elf64->e_ident[EI_CLASS] == ELFCLASS64	&&
+	      elf64->e_ident[EI_DATA]  == ELFDATA2MSB	&&
+	      elf64->e_type            == ET_EXEC	&&
+	      elf64->e_machine         == EM_PPC64))
+		return 0;
+
+	elf64ph = (Elf64_Phdr *)((unsigned long)elf64 +
+				 (unsigned long)elf64->e_phoff);
+	for (i = 0; i < (unsigned int)elf64->e_phnum; i++, elf64ph++)
+		if (elf64ph->p_type == PT_LOAD && elf64ph->p_offset != 0)
+			break;
+	if (i >= (unsigned int)elf64->e_phnum)
+		return 0;
+
+	elfoffset = (unsigned long)elf64ph->p_offset;
+	vmlinux.size = (unsigned long)elf64ph->p_filesz + elfoffset;
+	vmlinux.memsize = (unsigned long)elf64ph->p_memsz + elfoffset;
+	return 1;
+}
+
+static int is_elf32(void *hdr)
+{
+	Elf32_Ehdr *elf32 = hdr;
+	Elf32_Phdr *elf32ph;
+	unsigned int i;
+
+	if (!(elf32->e_ident[EI_MAG0]  == ELFMAG0	&&
+	      elf32->e_ident[EI_MAG1]  == ELFMAG1	&&
+	      elf32->e_ident[EI_MAG2]  == ELFMAG2	&&
+	      elf32->e_ident[EI_MAG3]  == ELFMAG3	&&
+	      elf32->e_ident[EI_CLASS] == ELFCLASS32	&&
+	      elf32->e_ident[EI_DATA]  == ELFDATA2MSB	&&
+	      elf32->e_type            == ET_EXEC	&&
+	      elf32->e_machine         == EM_PPC))
+		return 0;
+
+	elf32 = (Elf32_Ehdr *)elfheader;
+	elf32ph = (Elf32_Phdr *) ((unsigned long)elf32 + elf32->e_phoff);
+	for (i = 0; i < elf32->e_phnum; i++, elf32ph++)
+		if (elf32ph->p_type == PT_LOAD && elf32ph->p_offset != 0)
+			break;
+	if (i >= elf32->e_phnum)
+		return 0;
+
+	elfoffset = elf32ph->p_offset;
+	vmlinux.size = elf32ph->p_filesz + elf32ph->p_offset;
+	vmlinux.memsize = elf32ph->p_memsz + elf32ph->p_offset;
+	return 1;
+}
+
+void start(unsigned long a1, unsigned long a2, void *promptr, void *sp)
+{
+	int len;
+	kernel_entry_t kernel_entry;
+
+	memset(__bss_start, 0, _end - __bss_start);
+
+	prom = (int (*)(void *)) promptr;
+	chosen_handle = finddevice("/chosen");
+	if (chosen_handle == (void *) -1)
+		exit();
+	if (getprop(chosen_handle, "stdout", &stdout, sizeof(stdout)) != 4)
+		exit();
+	stderr = stdout;
+	if (getprop(chosen_handle, "stdin", &stdin, sizeof(stdin)) != 4)
+		exit();
+
+	printf("\n\rzImage starting: loaded at 0x%p (sp: 0x%p)\n\r", _start, sp);
+
+	vmlinuz.addr = (unsigned long)_vmlinux_start;
+	vmlinuz.size = (unsigned long)(_vmlinux_end - _vmlinux_start);
+
+	/* gunzip the ELF header of the kernel */
+	if (*(unsigned short *)vmlinuz.addr == 0x1f8b) {
+		len = vmlinuz.size;
+		gunzip(elfheader, sizeof(elfheader),
+				(unsigned char *)vmlinuz.addr, &len);
+	} else
+		memcpy(elfheader, (const void *)vmlinuz.addr, sizeof(elfheader));
+
+	if (!is_elf64(elfheader) && !is_elf32(elfheader)) {
+		printf("Error: not a valid PPC32 or PPC64 ELF file!\n\r");
+		exit();
+	}
+
+	/*
+	 * The first available claim_base must be above the end of the
+	 * the loaded kernel wrapper file (_start to _end includes the
+	 * initrd image if it is present) and rounded up to a nice
+	 * 1 MB boundary for good measure.
+	 */
+
+	claim_base = _ALIGN_UP((unsigned long)_end, ONE_MB);
+
+#if defined(PROG_START)
+	/*
+	 * Maintain a "magic" minimum address. This keeps some older
+	 * firmware platforms running.
+	 */
+
+	if (claim_base < PROG_START)
+		claim_base = PROG_START;
+#endif
+
+	/* We need to claim the memsize plus the file offset since gzip
+	 * will expand the header (file offset), then the kernel, then
+	 * possible rubbish we don't care about. But the kernel bss must
+	 * be claimed (it will be zero'd by the kernel itself)
+	 */
+	printf("Allocating 0x%lx bytes for kernel ...\n\r", vmlinux.memsize);
+	vmlinux.addr = try_claim(vmlinux.memsize);
+	if (vmlinux.addr == 0) {
+		printf("Can't allocate memory for kernel image !\n\r");
+		exit();
+	}
+
+	/*
+	 * Now we try to claim memory for the initrd (and copy it there)
+	 */
+	initrd.size = (unsigned long)(_initrd_end - _initrd_start);
+	initrd.memsize = initrd.size;
+	if ( initrd.size > 0 ) {
+		printf("Allocating 0x%lx bytes for initrd ...\n\r", initrd.size);
+		initrd.addr = try_claim(initrd.size);
+		if (initrd.addr == 0) {
+			printf("Can't allocate memory for initial ramdisk !\n\r");
+			exit();
+		}
+		a1 = initrd.addr;
+		a2 = initrd.size;
+		printf("initial ramdisk moving 0x%lx <- 0x%lx (0x%lx bytes)\n\r",
+		       initrd.addr, (unsigned long)_initrd_start, initrd.size);
+		memmove((void *)initrd.addr, (void *)_initrd_start, initrd.size);
+		printf("initrd head: 0x%lx\n\r", *((unsigned long *)initrd.addr));
+	}
+
+	/* Eventually gunzip the kernel */
+	if (*(unsigned short *)vmlinuz.addr == 0x1f8b) {
+		printf("gunzipping (0x%lx <- 0x%lx:0x%0lx)...",
+		       vmlinux.addr, vmlinuz.addr, vmlinuz.addr+vmlinuz.size);
+		len = vmlinuz.size;
+		gunzip((void *)vmlinux.addr, vmlinux.memsize,
+			(unsigned char *)vmlinuz.addr, &len);
+		printf("done 0x%lx bytes\n\r", len);
+	} else {
+		memmove((void *)vmlinux.addr,(void *)vmlinuz.addr,vmlinuz.size);
+	}
+
+	/* Skip over the ELF header */
+#ifdef DEBUG
+	printf("... skipping 0x%lx bytes of ELF header\n\r",
+			elfoffset);
+#endif
+	vmlinux.addr += elfoffset;
+
+	flush_cache((void *)vmlinux.addr, vmlinux.size);
+
+	kernel_entry = (kernel_entry_t)vmlinux.addr;
+#ifdef DEBUG
+	printf( "kernel:\n\r"
+		"        entry addr = 0x%lx\n\r"
+		"        a1         = 0x%lx,\n\r"
+		"        a2         = 0x%lx,\n\r"
+		"        prom       = 0x%lx,\n\r"
+		"        bi_recs    = 0x%lx,\n\r",
+		(unsigned long)kernel_entry, a1, a2,
+		(unsigned long)prom, NULL);
+#endif
+
+	kernel_entry(a1, a2, prom, NULL);
+
+	printf("Error: Linux kernel returned to zImage bootloader!\n\r");
+
+	exit();
+}
+