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-rw-r--r--arch/mn10300/boot/compressed/head.S151
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+/* 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