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-rw-r--r--arch/mn10300/kernel/gdb-cache.S105
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diff --git a/arch/mn10300/kernel/gdb-cache.S b/arch/mn10300/kernel/gdb-cache.S
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+###############################################################################
+#
+# MN10300 Low-level cache purging routines for gdbstub
+#
+# 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.
+#
+###############################################################################
+#include <linux/sys.h>
+#include <linux/linkage.h>
+#include <asm/smp.h>
+#include <asm/cache.h>
+#include <asm/cpu-regs.h>
+#include <asm/exceptions.h>
+#include <asm/frame.inc>
+#include <asm/serial-regs.h>
+
+ .text
+
+###############################################################################
+#
+# GDB stub cache purge
+#
+###############################################################################
+ .type gdbstub_purge_cache,@function
+ENTRY(gdbstub_purge_cache)
+ #######################################################################
+ # read the addresses tagged in the cache's tag RAM and attempt to flush
+ # those addresses specifically
+ # - we rely on the hardware to filter out invalid tag entry addresses
+ mov DCACHE_TAG(0,0),a0 # dcache tag RAM access address
+ mov DCACHE_PURGE(0,0),a1 # dcache purge request address
+ mov L1_CACHE_NWAYS*L1_CACHE_NENTRIES,d1 # total number of entries
+
+mn10300_dcache_flush_loop:
+ mov (a0),d0
+ and L1_CACHE_TAG_ADDRESS|L1_CACHE_TAG_ENTRY,d0
+ or L1_CACHE_TAG_VALID,d0 # retain valid entries in the
+ # cache
+ mov d0,(a1) # conditional purge
+
+mn10300_dcache_flush_skip:
+ add L1_CACHE_BYTES,a0
+ add L1_CACHE_BYTES,a1
+ add -1,d1
+ bne mn10300_dcache_flush_loop
+
+;; # unconditionally flush and invalidate the dcache
+;; mov DCACHE_PURGE(0,0),a1 # dcache purge request address
+;; mov L1_CACHE_NWAYS*L1_CACHE_NENTRIES,d1 # total number of
+;; # entries
+;;
+;; gdbstub_purge_cache__dcache_loop:
+;; mov (a1),d0 # unconditional purge
+;;
+;; add L1_CACHE_BYTES,a1
+;; add -1,d1
+;; bne gdbstub_purge_cache__dcache_loop
+
+ #######################################################################
+ # now invalidate the icache
+ mov CHCTR,a0
+ movhu (a0),a1
+
+ mov epsw,d1
+ and ~EPSW_IE,epsw
+ nop
+ nop
+
+ # disable the icache
+ and ~CHCTR_ICEN,d0
+ movhu d0,(a0)
+
+ # and wait for it to calm down
+ setlb
+ movhu (a0),d0
+ btst CHCTR_ICBUSY,d0
+ lne
+
+ # invalidate
+ or CHCTR_ICINV,d0
+ movhu d0,(a0)
+
+ # wait for the cache to finish
+ mov CHCTR,a0
+ setlb
+ movhu (a0),d0
+ btst CHCTR_ICBUSY,d0
+ lne
+
+ # and reenable it
+ movhu a1,(a0)
+ movhu (a0),d0 # read back to flush
+ # (SIGILLs all over without this)
+
+ mov d1,epsw
+
+ ret [],0
+
+ .size gdbstub_purge_cache,.-gdbstub_purge_cache