diff options
Diffstat (limited to 'arch/mn10300/boot/compressed/head.S')
-rw-r--r-- | arch/mn10300/boot/compressed/head.S | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/arch/mn10300/boot/compressed/head.S b/arch/mn10300/boot/compressed/head.S new file mode 100644 index 000000000..7b50345b9 --- /dev/null +++ b/arch/mn10300/boot/compressed/head.S @@ -0,0 +1,151 @@ +/* Boot entry point for a compressed MN10300 kernel + * + * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + .section .text + +#define DEBUG + +#include <linux/linkage.h> +#include <asm/cpu-regs.h> +#include <asm/cache.h> +#ifdef CONFIG_SMP +#include <proc/smp-regs.h> +#endif + + .globl startup_32 +startup_32: +#ifdef CONFIG_SMP + # + # Secondary CPUs jump directly to the kernel entry point + # + # Must save primary CPU's D0-D2 registers as they hold boot parameters + # + mov (CPUID), d3 + and CPUID_MASK,d3 + beq startup_primary + mov CONFIG_KERNEL_TEXT_ADDRESS,a0 + jmp (a0) + +startup_primary: +#endif /* CONFIG_SMP */ + + # first save parameters from bootloader + mov param_save_area,a0 + mov d0,(a0) + mov d1,(4,a0) + mov d2,(8,a0) + + mov sp,a3 + mov decomp_stack+0x2000-4,a0 + mov a0,sp + + # invalidate and enable both of the caches + mov CHCTR,a0 + clr d0 + movhu d0,(a0) # turn off first + mov CHCTR_ICINV|CHCTR_DCINV,d0 + movhu d0,(a0) + setlb + mov (a0),d0 + btst CHCTR_ICBUSY|CHCTR_DCBUSY,d0 # wait till not busy + lne + +#ifdef CONFIG_MN10300_CACHE_ENABLED +#ifdef CONFIG_MN10300_CACHE_WBACK + mov CHCTR_ICEN|CHCTR_DCEN|CHCTR_DCWTMD_WRBACK,d0 +#else + mov CHCTR_ICEN|CHCTR_DCEN|CHCTR_DCWTMD_WRTHROUGH,d0 +#endif /* WBACK */ + movhu d0,(a0) # enable +#endif /* !ENABLED */ + + # clear the BSS area + mov __bss_start,a0 + mov _end,a1 + clr d0 +bssclear: + cmp a1,a0 + bge bssclear_end + movbu d0,(a0) + inc a0 + bra bssclear +bssclear_end: + + # decompress the kernel + call decompress_kernel[],0 +#ifdef CONFIG_MN10300_CACHE_WBACK + call mn10300_dcache_flush_inv[],0 +#endif + + # disable caches again + mov CHCTR,a0 + clr d0 + movhu d0,(a0) + setlb + mov (a0),d0 + btst CHCTR_ICBUSY|CHCTR_DCBUSY,d0 # wait till not busy + lne + + mov param_save_area,a0 + mov (a0),d0 + mov (4,a0),d1 + mov (8,a0),d2 + + # jump to the kernel proper entry point + mov a3,sp + mov CONFIG_KERNEL_TEXT_ADDRESS,a0 + jmp (a0) + + +############################################################################### +# +# Cache flush routines +# +############################################################################### +#ifdef CONFIG_MN10300_CACHE_WBACK +mn10300_dcache_flush_inv: + movhu (CHCTR),d0 + btst CHCTR_DCEN,d0 + beq mn10300_dcache_flush_inv_end + + mov L1_CACHE_NENTRIES,d1 + clr a1 + +mn10300_dcache_flush_inv_loop: + mov (DCACHE_PURGE_WAY0(0),a1),d0 # unconditional purge + mov (DCACHE_PURGE_WAY1(0),a1),d0 # unconditional purge + mov (DCACHE_PURGE_WAY2(0),a1),d0 # unconditional purge + mov (DCACHE_PURGE_WAY3(0),a1),d0 # unconditional purge + + add L1_CACHE_BYTES,a1 + add -1,d1 + bne mn10300_dcache_flush_inv_loop + +mn10300_dcache_flush_inv_end: + ret [],0 +#endif /* CONFIG_MN10300_CACHE_WBACK */ + + +############################################################################### +# +# Data areas +# +############################################################################### + .data + .align 4 +param_save_area: + .rept 3 + .word 0 + .endr + + .section .bss + .align 4 +decomp_stack: + .space 0x2000 |