From d090dddaba7c8da6401bb259340dce05ca32f564 Mon Sep 17 00:00:00 2001 From: "Hyok S. Choi" Date: Wed, 28 Jun 2006 14:10:01 +0100 Subject: [ARM] nommu: Initial uCLinux support for MMU-based CPUs 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 Signed-off-by: Russell King --- arch/arm/mm/proc-arm925.S | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'arch/arm/mm/proc-arm925.S') diff --git a/arch/arm/mm/proc-arm925.S b/arch/arm/mm/proc-arm925.S index 224ce226a01b..8d47c9f3f931 100644 --- a/arch/arm/mm/proc-arm925.S +++ b/arch/arm/mm/proc-arm925.S @@ -9,6 +9,8 @@ * Update for Linux-2.6 and cache flush improvements * Copyright (C) 2004 Nokia Corporation by Tony Lindgren * + * hacked for non-paged-MM by Hyok S. Choi, 2004. + * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or @@ -122,7 +124,9 @@ ENTRY(cpu_arm925_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........ @@ -369,6 +373,7 @@ ENTRY(cpu_arm925_dcache_clean_area) */ .align 5 ENTRY(cpu_arm925_switch_mm) +#ifdef CONFIG_MMU mov ip, #0 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache @@ -383,6 +388,7 @@ ENTRY(cpu_arm925_switch_mm) mcr p15, 0, ip, c7, c10, 4 @ drain WB mcr p15, 0, r0, c2, c0, 0 @ load page table pointer mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs +#endif mov pc, lr /* @@ -392,6 +398,7 @@ ENTRY(cpu_arm925_switch_mm) */ .align 5 ENTRY(cpu_arm925_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 @@ -420,6 +427,7 @@ ENTRY(cpu_arm925_set_pte) mcr p15, 0, r0, c7, c10, 1 @ clean D entry #endif mcr p15, 0, r0, c7, c10, 4 @ drain WB +#endif /* CONFIG_MMU */ mov pc, lr __INIT @@ -438,7 +446,9 @@ __arm925_setup: mov r0, #0 mcr p15, 0, r0, c7, c7 @ invalidate I,D caches on v4 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4 +#ifdef CONFIG_MMU mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4 +#endif #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH mov r0, #4 @ disable write-back on caches explicitly -- cgit v1.2.1