summaryrefslogtreecommitdiff
path: root/arch/powerpc/boot/main.c
diff options
context:
space:
mode:
authorDavid Gibson <david@gibson.dropbear.id.au>2007-03-05 14:24:52 +1100
committerPaul Mackerras <paulus@samba.org>2007-03-13 13:35:01 +1100
commit79c8541924a220964f9f2cbed31eaa9fdb042eab (patch)
tree94e75bf65ea5cb0d40dfae7215ae432e1f914296 /arch/powerpc/boot/main.c
parentad9d2716cfc1cda5a7e0d7bc0db45e3af8a4adbb (diff)
[POWERPC] zImage: Cleanup and improve prep_kernel()
This patch rewrites prep_kernel() in the zImage wrapper code to be clearer and more flexible. Notable changes: - Handling of the initrd image from prep_kernel() has moved into a new prep_initrd() function. - The address of the initrd image is now added as device tree properties, as the kernel expects. - We only copy a packaged initrd image to a new location if it is in danger of being clobbered when the kernel moves to its final location, instead of always. - By default we decompress the kernel directly to address 0, instead of requiring it to relocate itself. Platforms (such as OF) where doing this could clobber still-live firmware data structures can override the vmlinux_alloc hook to provide an alternate place to decompress the kernel. - We no longer pass lots of information between functions in global variables. Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/boot/main.c')
-rw-r--r--arch/powerpc/boot/main.c167
1 files changed, 101 insertions, 66 deletions
diff --git a/arch/powerpc/boot/main.c b/arch/powerpc/boot/main.c
index 404620a9e733..05de6cfafeeb 100644
--- a/arch/powerpc/boot/main.c
+++ b/arch/powerpc/boot/main.c
@@ -33,24 +33,21 @@ extern char _dtb_end[];
static struct gunzip_state gzstate;
struct addr_range {
- unsigned long addr;
+ void *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 int is_64bit;
-static char elfheader[256];
+struct elf_info {
+ unsigned long loadsize;
+ unsigned long memsize;
+ unsigned long elfoffset;
+};
typedef void (*kernel_entry_t)(unsigned long, unsigned long, void *);
#undef DEBUG
-static int is_elf64(void *hdr)
+static int parse_elf64(void *hdr, struct elf_info *info)
{
Elf64_Ehdr *elf64 = hdr;
Elf64_Phdr *elf64ph;
@@ -74,15 +71,14 @@ static int is_elf64(void *hdr)
if (i >= (unsigned int)elf64->e_phnum)
return 0;
- elfoffset = (unsigned long)elf64ph->p_offset;
- vmlinux.size = (unsigned long)elf64ph->p_filesz;
- vmlinux.memsize = (unsigned long)elf64ph->p_memsz;
+ info->loadsize = (unsigned long)elf64ph->p_filesz;
+ info->memsize = (unsigned long)elf64ph->p_memsz;
+ info->elfoffset = (unsigned long)elf64ph->p_offset;
- is_64bit = 1;
return 1;
}
-static int is_elf32(void *hdr)
+static int parse_elf32(void *hdr, struct elf_info *info)
{
Elf32_Ehdr *elf32 = hdr;
Elf32_Phdr *elf32ph;
@@ -98,7 +94,6 @@ static int is_elf32(void *hdr)
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)
@@ -106,24 +101,26 @@ static int is_elf32(void *hdr)
if (i >= elf32->e_phnum)
return 0;
- elfoffset = elf32ph->p_offset;
- vmlinux.size = elf32ph->p_filesz;
- vmlinux.memsize = elf32ph->p_memsz;
+ info->loadsize = elf32ph->p_filesz;
+ info->memsize = elf32ph->p_memsz;
+ info->elfoffset = elf32ph->p_offset;
return 1;
}
-static void prep_kernel(unsigned long a1, unsigned long a2)
+static struct addr_range prep_kernel(void)
{
+ char elfheader[256];
+ void *vmlinuz_addr = _vmlinux_start;
+ unsigned long vmlinuz_size = _vmlinux_end - _vmlinux_start;
+ void *addr = 0;
+ struct elf_info ei;
int len;
- vmlinuz.addr = (unsigned long)_vmlinux_start;
- vmlinuz.size = (unsigned long)(_vmlinux_end - _vmlinux_start);
-
/* gunzip the ELF header of the kernel */
- gunzip_start(&gzstate, (void *)vmlinuz.addr, vmlinuz.size);
+ gunzip_start(&gzstate, vmlinuz_addr, vmlinuz_size);
gunzip_exactly(&gzstate, elfheader, sizeof(elfheader));
- if (!is_elf64(elfheader) && !is_elf32(elfheader)) {
+ if (!parse_elf64(elfheader, &ei) && !parse_elf32(elfheader, &ei)) {
printf("Error: not a valid PPC32 or PPC64 ELF file!\n\r");
exit();
}
@@ -135,55 +132,92 @@ static void prep_kernel(unsigned long a1, unsigned long a2)
* 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 = (unsigned long)malloc(vmlinux.memsize);
- if (vmlinux.addr == 0) {
- printf("Can't allocate memory for kernel image !\n\r");
- exit();
+ printf("Allocating 0x%lx bytes for kernel ...\n\r", ei.memsize);
+
+ if (platform_ops.vmlinux_alloc) {
+ addr = platform_ops.vmlinux_alloc(ei.memsize);
+ } else {
+ if ((unsigned long)_start < ei.memsize) {
+ printf("Insufficient memory for kernel at address 0!"
+ " (_start=%lx)\n\r", _start);
+ exit();
+ }
}
+ /* Finally, gunzip the kernel */
+ printf("gunzipping (0x%p <- 0x%p:0x%p)...", addr,
+ vmlinuz_addr, vmlinuz_addr+vmlinuz_size);
+ /* discard up to the actual load data */
+ gunzip_discard(&gzstate, ei.elfoffset - sizeof(elfheader));
+ len = gunzip_finish(&gzstate, addr, ei.memsize);
+ printf("done 0x%lx bytes\n\r", len);
+
+ flush_cache(addr, ei.loadsize);
+
+ return (struct addr_range){addr, ei.memsize};
+}
+
+static struct addr_range prep_initrd(struct addr_range vmlinux,
+ unsigned long initrd_addr,
+ unsigned long initrd_size)
+{
+ void *devp;
+ u32 initrd_start, initrd_end;
+
+ /* If we have an image attached to us, it overrides anything
+ * supplied by the loader. */
+ if (_initrd_end > _initrd_start) {
+ printf("Attached initrd image at 0x%p-0x%p\n\r",
+ _initrd_start, _initrd_end);
+ initrd_addr = (unsigned long)_initrd_start;
+ initrd_size = _initrd_end - _initrd_start;
+ } else if (initrd_size > 0) {
+ printf("Using loader supplied ramdisk at 0x%lx-0x%lx\n\r",
+ initrd_addr, initrd_addr + initrd_size);
+ }
+
+ /* If there's no initrd at all, we're done */
+ if (! initrd_size)
+ return (struct addr_range){0, 0};
+
/*
- * Now find the initrd
- *
- * First see if we have an image attached to us. If so
- * allocate memory for it and copy it there.
+ * If the initrd is too low it will be clobbered when the
+ * kernel relocates to its final location. In this case,
+ * allocate a safer place and move it.
*/
- initrd.size = (unsigned long)(_initrd_end - _initrd_start);
- initrd.memsize = initrd.size;
- if (initrd.size > 0) {
+ if (initrd_addr < vmlinux.size) {
+ void *old_addr = (void *)initrd_addr;
+
printf("Allocating 0x%lx bytes for initrd ...\n\r",
- initrd.size);
- initrd.addr = (unsigned long)malloc((u32)initrd.size);
- if (initrd.addr == 0) {
+ initrd_size);
+ initrd_addr = (unsigned long)malloc(initrd_size);
+ if (! initrd_addr) {
printf("Can't allocate memory for initial "
- "ramdisk !\n\r");
+ "ramdisk !\n\r");
exit();
}
- 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));
- } else if (a2 != 0) {
- /* Otherwise, see if yaboot or another loader gave us an initrd */
- initrd.addr = a1;
- initrd.memsize = initrd.size = a2;
- printf("Using loader supplied initrd at 0x%lx (0x%lx bytes)\n\r",
- initrd.addr, initrd.size);
+ printf("Relocating initrd 0x%p <- 0x%p (0x%lx bytes)\n\r",
+ initrd_addr, old_addr, initrd_size);
+ memmove((void *)initrd_addr, old_addr, initrd_size);
}
- /* Eventually gunzip the kernel */
- printf("gunzipping (0x%lx <- 0x%lx:0x%0lx)...",
- vmlinux.addr, vmlinuz.addr, vmlinuz.addr+vmlinuz.size);
- /* discard up to the actual load data */
- gunzip_discard(&gzstate, elfoffset - sizeof(elfheader));
- len = gunzip_finish(&gzstate, (void *)vmlinux.addr,
- vmlinux.memsize);
- printf("done 0x%lx bytes\n\r", len);
+ printf("initrd head: 0x%lx\n\r", *((unsigned long *)initrd_addr));
+
+ /* Tell the kernel initrd address via device tree */
+ devp = finddevice("/chosen");
+ if (! devp) {
+ printf("Device tree has no chosen node!\n\r");
+ exit();
+ }
+
+ initrd_start = (u32)initrd_addr;
+ initrd_end = (u32)initrd_addr + initrd_size;
+
+ setprop(devp, "linux,initrd-start", &initrd_start,
+ sizeof(initrd_start));
+ setprop(devp, "linux,initrd-end", &initrd_end, sizeof(initrd_end));
- flush_cache((void *)vmlinux.addr, vmlinux.size);
+ return (struct addr_range){(void *)initrd_addr, initrd_size};
}
/* A buffer that may be edited by tools operating on a zImage binary so as to
@@ -223,6 +257,7 @@ struct console_ops console_ops;
void start(unsigned long a1, unsigned long a2, void *promptr, void *sp)
{
+ struct addr_range vmlinux, initrd;
kernel_entry_t kentry;
char cmdline[COMMAND_LINE_SIZE];
unsigned long ft_addr = 0;
@@ -242,7 +277,8 @@ void start(unsigned long a1, unsigned long a2, void *promptr, void *sp)
printf("\n\rzImage starting: loaded at 0x%p (sp: 0x%p)\n\r",
_start, sp);
- prep_kernel(a1, a2);
+ vmlinux = prep_kernel();
+ initrd = prep_initrd(vmlinux, a1, a2);
/* If cmdline came from zimage wrapper or if we can edit the one
* in the dt, print it out and edit it, if possible.
@@ -271,8 +307,7 @@ void start(unsigned long a1, unsigned long a2, void *promptr, void *sp)
if (ft_addr)
kentry(ft_addr, 0, NULL);
else
- /* XXX initrd addr/size should be passed in properties */
- kentry(initrd.addr, initrd.size, promptr);
+ kentry((unsigned long)initrd.addr, initrd.size, promptr);
/* console closed so printf below may not work */
printf("Error: Linux kernel returned to zImage boot wrapper!\n\r");