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-rw-r--r--arch/h8300/kernel/head_rom.S110
1 files changed, 110 insertions, 0 deletions
diff --git a/arch/h8300/kernel/head_rom.S b/arch/h8300/kernel/head_rom.S
new file mode 100644
index 000000000000..9868a4121a1f
--- /dev/null
+++ b/arch/h8300/kernel/head_rom.S
@@ -0,0 +1,110 @@
+#include <linux/init.h>
+#include <asm/thread_info.h>
+
+#if defined(CONFIG_CPU_H8300H)
+ .h8300h
+#define SYSCR 0xfee012
+#define IRAMTOP 0xffff20
+#define NR_INT 64
+#endif
+#if defined(CONFIG_CPU_H8S)
+ .h8300s
+#define INTCR 0xffff31
+#define IRAMTOP 0xffc000
+#define NR_INT 128
+#endif
+
+ __HEAD
+ .global _start
+_start:
+ mov.l #IRAMTOP,sp
+#if !defined(CONFIG_H8300H_SIM) && \
+ !defined(CONFIG_H8S_SIM)
+ jsr @lowlevel_init
+
+ /* copy .data */
+ mov.l #_begin_data,er5
+ mov.l #_sdata,er6
+ mov.l #_edata,er4
+ sub.l er6,er4
+ shlr.l er4
+ shlr.l er4
+1:
+ mov.l @er5+,er0
+ mov.l er0,@er6
+ adds #4,er6
+ dec.l #1,er4
+ bne 1b
+ /* .bss clear */
+ mov.l #_sbss,er5
+ mov.l #_ebss,er4
+ sub.l er5,er4
+ shlr er4
+ shlr er4
+ sub.l er0,er0
+1:
+ mov.l er0,@er5
+ adds #4,er5
+ dec.l #1,er4
+ bne 1b
+#else
+ /* get cmdline from gdb */
+ jsr @0xcc
+ ;; er0 - argc
+ ;; er1 - argv
+ mov.l #command_line,er3
+ adds #4,er1
+ dec.l #1,er0
+ beq 4f
+1:
+ mov.l @er1+,er2
+2:
+ mov.b @er2+,r4l
+ beq 3f
+ mov.b r4l,@er3
+ adds #1,er3
+ bra 2b
+3:
+ mov.b #' ',r4l
+ mov.b r4l,@er3
+ adds #1,er3
+ dec.l #1,er0
+ bne 1b
+ subs #1,er3
+ mov.b #0,r4l
+ mov.b r4l,@er3
+4:
+#endif
+ sub.l er0,er0
+ jsr @h8300_fdt_init
+ /* linux kernel start */
+#if defined(CONFIG_CPU_H8300H)
+ ldc #0xd0,ccr /* running kernel */
+ mov.l #SYSCR,er0
+ bclr #3,@er0
+#endif
+#if defined(CONFIG_CPU_H8S)
+ ldc #0x07,exr
+ bclr #4,@INTCR:8
+ bset #5,@INTCR:8 /* Interrupt mode 2 */
+ ldc #0x90,ccr /* running kernel */
+#endif
+ mov.l #init_thread_union,sp
+ add.l #0x2000,sp
+ jsr @start_kernel
+
+1:
+ bra 1b
+
+#if defined(CONFIG_ROMKERNEL)
+ /* interrupt vector */
+ .section .vectors,"ax"
+ .long _start
+ .long _start
+vector = 2
+ .rept NR_INT - 2
+ .long _interrupt_redirect_table+vector*4
+vector = vector + 1
+ .endr
+#endif
+ .end