[PATCH] m68knommu: startup code for the Drangen Engine 68328 based board

Specialized startup code for the 68328 based DragenEngine board.
It doesn't easily fit into the common 68x328 startup code framework.
It doesn't want any of the common hardware setup to be done here.

Signed-off-by: Greg Ungerer <gerg@uclinux.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 135 insertions, 0 deletions

diff --git a/arch/m68knommu/platform/68328/head-de2.S b/arch/m68knommu/platform/68328/head-de2.S
new file mode 100644
index 000000000000..94c5a1609a75
--- /dev/null
+++ b/arch/m68knommu/platform/68328/head-de2.S
@@ -0,0 +1,135 @@
+#include <linux/config.h>
+
+#if defined(CONFIG_RAM32MB)
+#define MEM_END 0x02000000      /* Memory size 32Mb */
+#elif defined(CONFIG_RAM16MB)
+#define MEM_END 0x01000000      /* Memory size 16Mb */
+#else
+#define MEM_END 0x00800000      /* Memory size 8Mb */
+#endif
+
+#undef CRT_DEBUG
+
+.macro  PUTC CHAR
+#ifdef CRT_DEBUG
+        moveq   #\CHAR, %d7
+        jsr     putc
+#endif
+.endm
+
+        .global _start
+        .global _rambase
+        .global _ramvec
+        .global _ramstart
+        .global _ramend
+        
+        .data
+
+/*
+ *      Set up the usable of RAM stuff
+ */
+_rambase:
+        .long   0
+_ramvec:
+        .long   0
+_ramstart:
+        .long   0
+_ramend:
+        .long   0
+
+        .text
+
+_start:
+
+/*
+ * Setup initial stack
+ */
+        /* disable all interrupts */
+        movew   #0x2700, %sr
+        movel   #-1, 0xfffff304
+        movel   #MEM_END-4, %sp
+
+        PUTC    '\r'
+        PUTC    '\n'
+        PUTC    'A'
+        PUTC    'B'
+
+/*
+ *      Determine end of RAM
+ */
+
+        movel   #MEM_END, %a0
+        movel   %a0, _ramend
+
+        PUTC    'C'
+
+/*
+ *      Move ROM filesystem above bss :-)
+ */
+
+        moveal  #_sbss, %a0                     /* romfs at the start of bss */
+        moveal  #_ebss, %a1                     /* Set up destination  */
+        movel   %a0, %a2                        /* Copy of bss start */
+
+        movel   8(%a0), %d1                     /* Get size of ROMFS */
+        addql   #8, %d1                         /* Allow for rounding */
+        andl    #0xfffffffc, %d1        /* Whole words */
+
+        addl    %d1, %a0                        /* Copy from end */
+        addl    %d1, %a1                        /* Copy from end */
+        movel   %a1, _ramstart          /* Set start of ram */
+
+1:
+        movel   -(%a0), %d0                     /* Copy dword */
+        movel   %d0, -(%a1)
+        cmpl    %a0, %a2                        /* Check if at end */
+        bne     1b
+
+        PUTC    'D'
+
+/*
+ * Initialize BSS segment to 0
+ */
+
+        lea     _sbss, %a0
+        lea     _ebss, %a1
+
+        /* Copy 0 to %a0 until %a0 == %a1 */
+2:      cmpal   %a0, %a1
+        beq     1f
+        clrl    (%a0)+
+        bra     2b
+1:
+
+        PUTC    'E'
+
+/*
+ * Load the current task pointer and stack
+ */
+
+        lea     init_thread_union, %a0
+        lea     0x2000(%a0), %sp
+
+        PUTC    'F'
+        PUTC    '\r'
+        PUTC    '\n'
+
+/*
+ * Go
+ */
+
+        jmp     start_kernel
+
+/*
+ * Local functions
+ */
+ 
+#ifdef CRT_DEBUG
+putc:
+        moveb   %d7, 0xfffff907
+1:
+        movew   0xfffff906, %d7
+        andw    #0x2000, %d7
+        beq     1b
+        rts
+#endif