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-rw-r--r--arch/m68knommu/platform/68328/head-de2.S135
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 00000000000..94c5a1609a7
--- /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