8 files changed, 61 insertions, 23 deletions

diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
index 3628d8681844..b1fc029e5ea7 100644
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile
@@ -40,11 +40,11 @@ zliblinuxheader := zlib.h zconf.h zutil.h
 $(addprefix $(obj)/,$(zlib) main.o): $(addprefix $(obj)/,$(zliblinuxheader)) \
                 $(addprefix $(obj)/,$(zlibheader))
 
-src-wlib := string.S stdio.c main.c flatdevtree.c flatdevtree_misc.c \
+src-wlib := string.S crt0.S stdio.c main.c flatdevtree.c flatdevtree_misc.c \
                 ns16550.c serial.c simple_alloc.c div64.S util.S \
                 gunzip_util.c $(zlib)
 src-plat := of.c
-src-boot := crt0.S $(src-wlib) $(src-plat) empty.c
+src-boot := $(src-wlib) $(src-plat) empty.c
 
 src-boot := $(addprefix $(obj)/, $(src-boot))
 obj-boot := $(addsuffix .o, $(basename $(src-boot)))
@@ -97,7 +97,7 @@ $(obj)/wrapper.a: $(obj-wlib)
 
 hostprogs-y     := addnote addRamDisk hack-coff mktree
 
-extra-y         := $(obj)/crt0.o $(obj)/wrapper.a $(obj-plat) $(obj)/empty.o \
+extra-y         := $(obj)/wrapper.a $(obj-plat) $(obj)/empty.o \
                    $(obj)/zImage.lds $(obj)/zImage.coff.lds
 
 wrapper         :=$(srctree)/$(src)/wrapper
diff --git a/arch/powerpc/boot/crt0.S b/arch/powerpc/boot/crt0.S
index 70e65b13e033..3dc8d8f78499 100644
--- a/arch/powerpc/boot/crt0.S
+++ b/arch/powerpc/boot/crt0.S
@@ -16,6 +16,7 @@
 _zimage_start_opd:
         .long   _zimage_start, 0, 0, 0
 
+        .weak   _zimage_start
         .globl  _zimage_start
 _zimage_start:
         /* Work out the offset between the address we were linked at
@@ -44,7 +45,7 @@ _zimage_start:
         addi    r9,r9,4
         bdnz    2b
 
-        /* Do a cache flush for our text, in case OF didn't */
+        /* Do a cache flush for our text, in case the loader didn't */
 3:      lis     r9,_start@ha
         addi    r9,r9,_start@l
         add     r9,r0,r9
@@ -59,6 +60,31 @@ _zimage_start:
         sync
         isync
 
-        mr      r6,r1
-        b       start
+        /* Clear the BSS */
+        lis     r9,__bss_start@ha
+        addi    r9,r9,__bss_start@l
+        lis     r8,_end@ha
+        addi    r8,r8,_end@l
+        li      r0,0
+5:      stw     r0,0(r9)
+        addi    r9,r9,4
+        cmplw   cr0,r9,r8
+        blt     5b
 
+        /* Possibly set up a custom stack */
+.weak   _platform_stack_top
+        lis     r8,_platform_stack_top@ha
+        addi    r8,r8,_platform_stack_top@l
+        cmpwi   r8,0
+        beq     6f
+        lwz     r1,0(r8)
+        li      r0,0
+        stwu    r0,-16(r1)      /* establish a stack frame */
+6:
+
+        /* Call platform_init() */
+        bl      platform_init
+
+        /* Call start */
+        mr      r3,r1
+        b       start
diff --git a/arch/powerpc/boot/main.c b/arch/powerpc/boot/main.c
index 05de6cfafeeb..8a60e13777d7 100644
--- a/arch/powerpc/boot/main.c
+++ b/arch/powerpc/boot/main.c
@@ -254,21 +254,15 @@ static void set_cmdline(char *buf)
 struct platform_ops platform_ops;
 struct dt_ops dt_ops;
 struct console_ops console_ops;
+struct loader_info loader_info;
 
-void start(unsigned long a1, unsigned long a2, void *promptr, void *sp)
+void start(void *sp)
 {
         struct addr_range vmlinux, initrd;
         kernel_entry_t kentry;
         char cmdline[COMMAND_LINE_SIZE];
         unsigned long ft_addr = 0;
 
-        memset(__bss_start, 0, _end - __bss_start);
-        memset(&platform_ops, 0, sizeof(platform_ops));
-        memset(&dt_ops, 0, sizeof(dt_ops));
-        memset(&console_ops, 0, sizeof(console_ops));
-
-        if (platform_init(promptr, _dtb_start, _dtb_end))
-                exit();
         if (console_ops.open && (console_ops.open() < 0))
                 exit();
         if (platform_ops.fixups)
@@ -278,7 +272,8 @@ void start(unsigned long a1, unsigned long a2, void *promptr, void *sp)
                _start, sp);
 
         vmlinux = prep_kernel();
-        initrd = prep_initrd(vmlinux, a1, a2);
+        initrd = prep_initrd(vmlinux, loader_info.initrd_addr,
+                             loader_info.initrd_size);
 
         /* If cmdline came from zimage wrapper or if we can edit the one
          * in the dt, print it out and edit it, if possible.
@@ -298,7 +293,7 @@ void start(unsigned long a1, unsigned long a2, void *promptr, void *sp)
         if (ft_addr)
                 printf(" flat tree at 0x%lx\n\r", ft_addr);
         else
-                printf(" using OF tree (promptr=%p)\n\r", promptr);
+                printf(" using OF tree (promptr=%p)\n\r", loader_info.promptr);
 
         if (console_ops.close)
                 console_ops.close();
@@ -307,7 +302,8 @@ void start(unsigned long a1, unsigned long a2, void *promptr, void *sp)
         if (ft_addr)
                 kentry(ft_addr, 0, NULL);
         else
-                kentry((unsigned long)initrd.addr, initrd.size, promptr);
+                kentry((unsigned long)initrd.addr, initrd.size,
+                       loader_info.promptr);
 
         /* console closed so printf below may not work */
         printf("Error: Linux kernel returned to zImage boot wrapper!\n\r");
diff --git a/arch/powerpc/boot/of.c b/arch/powerpc/boot/of.c
index 044f34770b96..c6f0d9701485 100644
--- a/arch/powerpc/boot/of.c
+++ b/arch/powerpc/boot/of.c
@@ -267,7 +267,7 @@ static void of_console_write(char *buf, int len)
         call_prom("write", 3, 1, of_stdout_handle, buf, len);
 }
 
-int platform_init(void *promptr, char *dt_blob_start, char *dt_blob_end)
+void platform_init(unsigned long a1, unsigned long a2, void *promptr)
 {
         platform_ops.image_hdr = of_image_hdr;
         platform_ops.malloc = of_try_claim;
@@ -282,5 +282,7 @@ int platform_init(void *promptr, char *dt_blob_start, char *dt_blob_end)
         console_ops.write = of_console_write;
 
         prom = (int (*)(void *))promptr;
-        return 0;
+        loader_info.promptr = promptr;
+        loader_info.initrd_addr = a1;
+        loader_info.initrd_size = a2;
 }
diff --git a/arch/powerpc/boot/ops.h b/arch/powerpc/boot/ops.h
index fa62ff223e70..cad4eee599fb 100644
--- a/arch/powerpc/boot/ops.h
+++ b/arch/powerpc/boot/ops.h
@@ -59,7 +59,13 @@ struct serial_console_data {
         void            (*close)(void);
 };
 
-int platform_init(void *promptr, char *dt_blob_start, char *dt_blob_end);
+struct loader_info {
+        void *promptr;
+        unsigned long initrd_addr, initrd_size;
+};
+extern struct loader_info loader_info;
+
+void start(void *sp);
 int ft_init(void *dt_blob, unsigned int max_size, unsigned int max_find_device);
 int serial_console_init(void);
 int ns16550_console_init(void *devp, struct serial_console_data *scdp);
@@ -100,4 +106,8 @@ static inline void exit(void)
         for(;;);
 }
 
+#define BSS_STACK(size) \
+        static char _bss_stack[size]; \
+        void *_platform_stack_top = _bss_stack + sizeof(_bss_stack);
+
 #endif /* _PPC_BOOT_OPS_H_ */
diff --git a/arch/powerpc/boot/wrapper b/arch/powerpc/boot/wrapper
index 024e4d425c59..157d8c89e138 100755
--- a/arch/powerpc/boot/wrapper
+++ b/arch/powerpc/boot/wrapper
@@ -191,7 +191,7 @@ fi
 
 if [ "$platform" != "miboot" ]; then
     ${CROSS}ld -m elf32ppc -T $lds -o "$ofile" \
-        $object/crt0.o $platformo $tmp $object/wrapper.a
+        $platformo $tmp $object/wrapper.a
     rm $tmp
 fi
 
@@ -201,7 +201,9 @@ pseries|chrp)
     $object/addnote "$ofile"
     ;;
 pmaccoff)
-    ${CROSS}objcopy -O aixcoff-rs6000 --set-start 0x500000 "$ofile"
+    entry=`objdump -f "$ofile" | grep '^start address ' | \
+        cut -d' ' -f3`
+    ${CROSS}objcopy -O aixcoff-rs6000 --set-start "$entry" "$ofile"
     $object/hack-coff "$ofile"
     ;;
 esac
diff --git a/arch/powerpc/boot/zImage.coff.lds.S b/arch/powerpc/boot/zImage.coff.lds.S
index a360905e5428..fe87a90ce7f1 100644
--- a/arch/powerpc/boot/zImage.coff.lds.S
+++ b/arch/powerpc/boot/zImage.coff.lds.S
@@ -1,5 +1,6 @@
 OUTPUT_ARCH(powerpc:common)
-ENTRY(_start)
+ENTRY(_zimage_start_opd)
+EXTERN(_zimage_start_opd)
 SECTIONS
 {
   . = (5*1024*1024);
diff --git a/arch/powerpc/boot/zImage.lds.S b/arch/powerpc/boot/zImage.lds.S
index 4be3c6414b04..f6e380fdb388 100644
--- a/arch/powerpc/boot/zImage.lds.S
+++ b/arch/powerpc/boot/zImage.lds.S
@@ -1,5 +1,6 @@
 OUTPUT_ARCH(powerpc:common)
 ENTRY(_zimage_start)
+EXTERN(_zimage_start)
 SECTIONS
 {
   . = (4*1024*1024);