| David Howells | b920de1 | 2008-02-08 04:19:31 -0800 | [diff] [blame] | 1 | ############################################################################### |
| 2 | # |
| 3 | # MN10300 Low-level cache purging routines for gdbstub |
| 4 | # |
| 5 | # Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. |
| 6 | # Written by David Howells (dhowells@redhat.com) |
| 7 | # |
| 8 | # This program is free software; you can redistribute it and/or |
| 9 | # modify it under the terms of the GNU General Public Licence |
| 10 | # as published by the Free Software Foundation; either version |
| 11 | # 2 of the Licence, or (at your option) any later version. |
| 12 | # |
| 13 | ############################################################################### |
| 14 | #include <linux/sys.h> |
| 15 | #include <linux/linkage.h> |
| 16 | #include <asm/smp.h> |
| 17 | #include <asm/cache.h> |
| 18 | #include <asm/cpu-regs.h> |
| 19 | #include <asm/exceptions.h> |
| 20 | #include <asm/frame.inc> |
| 21 | #include <asm/serial-regs.h> |
| 22 | |
| 23 | .text |
| 24 | |
| 25 | ############################################################################### |
| 26 | # |
| 27 | # GDB stub cache purge |
| 28 | # |
| 29 | ############################################################################### |
| 30 | .type gdbstub_purge_cache,@function |
| 31 | ENTRY(gdbstub_purge_cache) |
| 32 | ####################################################################### |
| 33 | # read the addresses tagged in the cache's tag RAM and attempt to flush |
| 34 | # those addresses specifically |
| 35 | # - we rely on the hardware to filter out invalid tag entry addresses |
| 36 | mov DCACHE_TAG(0,0),a0 # dcache tag RAM access address |
| 37 | mov DCACHE_PURGE(0,0),a1 # dcache purge request address |
| 38 | mov L1_CACHE_NWAYS*L1_CACHE_NENTRIES,d1 # total number of entries |
| 39 | |
| 40 | mn10300_dcache_flush_loop: |
| 41 | mov (a0),d0 |
| 42 | and L1_CACHE_TAG_ADDRESS|L1_CACHE_TAG_ENTRY,d0 |
| 43 | or L1_CACHE_TAG_VALID,d0 # retain valid entries in the |
| 44 | # cache |
| 45 | mov d0,(a1) # conditional purge |
| 46 | |
| 47 | mn10300_dcache_flush_skip: |
| 48 | add L1_CACHE_BYTES,a0 |
| 49 | add L1_CACHE_BYTES,a1 |
| 50 | add -1,d1 |
| 51 | bne mn10300_dcache_flush_loop |
| 52 | |
| 53 | ;; # unconditionally flush and invalidate the dcache |
| 54 | ;; mov DCACHE_PURGE(0,0),a1 # dcache purge request address |
| 55 | ;; mov L1_CACHE_NWAYS*L1_CACHE_NENTRIES,d1 # total number of |
| 56 | ;; # entries |
| 57 | ;; |
| 58 | ;; gdbstub_purge_cache__dcache_loop: |
| 59 | ;; mov (a1),d0 # unconditional purge |
| 60 | ;; |
| 61 | ;; add L1_CACHE_BYTES,a1 |
| 62 | ;; add -1,d1 |
| 63 | ;; bne gdbstub_purge_cache__dcache_loop |
| 64 | |
| 65 | ####################################################################### |
| 66 | # now invalidate the icache |
| 67 | mov CHCTR,a0 |
| 68 | movhu (a0),a1 |
| 69 | |
| 70 | mov epsw,d1 |
| 71 | and ~EPSW_IE,epsw |
| 72 | nop |
| 73 | nop |
| 74 | |
| 75 | # disable the icache |
| 76 | and ~CHCTR_ICEN,d0 |
| 77 | movhu d0,(a0) |
| 78 | |
| 79 | # and wait for it to calm down |
| 80 | setlb |
| 81 | movhu (a0),d0 |
| 82 | btst CHCTR_ICBUSY,d0 |
| 83 | lne |
| 84 | |
| 85 | # invalidate |
| 86 | or CHCTR_ICINV,d0 |
| 87 | movhu d0,(a0) |
| 88 | |
| 89 | # wait for the cache to finish |
| 90 | mov CHCTR,a0 |
| 91 | setlb |
| 92 | movhu (a0),d0 |
| 93 | btst CHCTR_ICBUSY,d0 |
| 94 | lne |
| 95 | |
| 96 | # and reenable it |
| 97 | movhu a1,(a0) |
| 98 | movhu (a0),d0 # read back to flush |
| 99 | # (SIGILLs all over without this) |
| 100 | |
| 101 | mov d1,epsw |
| 102 | |
| 103 | ret [],0 |
| 104 | |
| 105 | .size gdbstub_purge_cache,.-gdbstub_purge_cache |