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();
+}
+