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[ARM] nommu: Initial uCLinux support for MMU-based CPUs

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In noMMU mode, various of functions which are defined in mm/proc-*.S
is not valid or needed to be avoided. i.g. switch_mm is not needed,
just returns and this makes the I & D caches are valid which shows
great improvement of performance including task switching and IPC.

Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Hyok S. Choi
2006-06-28 14:10:01 +01:00
committed by Russell King
parent a4f7e76367
commit d090dddaba
13 changed files with 129 additions and 0 deletions
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11
arch/arm/mm/proc-sa110.S
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@@ -2,6 +2,7 @@
* linux/arch/arm/mm/proc-sa110.S
*
* Copyright (C) 1997-2002 Russell King
* hacked for non-paged-MM by Hyok S. Choi, 2003.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
@@ -67,7 +68,9 @@ ENTRY(cpu_sa110_reset)
mov ip, #0
mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches
mcr p15, 0, ip, c7, c10, 4 @ drain WB
#ifdef CONFIG_MMU
mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
#endif
mrc p15, 0, ip, c1, c0, 0 @ ctrl register
bic ip, ip, #0x000f @ ............wcam
bic ip, ip, #0x1100 @ ...i...s........
@@ -130,11 +133,15 @@ ENTRY(cpu_sa110_dcache_clean_area)
*/
.align 5
ENTRY(cpu_sa110_switch_mm)
#ifdef CONFIG_MMU
str lr, [sp, #-4]!
bl v4wb_flush_kern_cache_all @ clears IP
mcr p15, 0, r0, c2, c0, 0 @ load page table pointer
mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
ldr pc, [sp], #4
#else
mov pc, lr
#endif
/*
* cpu_sa110_set_pte(ptep, pte)
@@ -143,6 +150,7 @@ ENTRY(cpu_sa110_switch_mm)
*/
.align 5
ENTRY(cpu_sa110_set_pte)
#ifdef CONFIG_MMU
str r1, [r0], #-2048 @ linux version
eor r1, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_WRITE | L_PTE_DIRTY
@@ -164,6 +172,7 @@ ENTRY(cpu_sa110_set_pte)
mov r0, r0
mcr p15, 0, r0, c7, c10, 1 @ clean D entry
mcr p15, 0, r0, c7, c10, 4 @ drain WB
#endif
mov pc, lr
__INIT
@@ -173,7 +182,9 @@ __sa110_setup:
mov r10, #0
mcr p15, 0, r10, c7, c7 @ invalidate I,D caches on v4
mcr p15, 0, r10, c7, c10, 4 @ drain write buffer on v4
#ifdef CONFIG_MMU
mcr p15, 0, r10, c8, c7 @ invalidate I,D TLBs on v4
#endif
mrc p15, 0, r0, c1, c0 @ get control register v4
ldr r5, sa110_cr1_clear
bic r0, r0, r5