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-arm920.S | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'arch/arm/mm/proc-arm920.S') diff --git a/arch/arm/mm/proc-arm920.S b/arch/arm/mm/proc-arm920.S index a17f79e0199..31dc839ba07 100644 --- a/arch/arm/mm/proc-arm920.S +++ b/arch/arm/mm/proc-arm920.S @@ -3,6 +3,7 @@ * * Copyright (C) 1999,2000 ARM Limited * Copyright (C) 2000 Deep Blue Solutions Ltd. + * 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 as published by @@ -97,7 +98,9 @@ ENTRY(cpu_arm920_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........ @@ -317,6 +320,7 @@ ENTRY(cpu_arm920_dcache_clean_area) */ .align 5 ENTRY(cpu_arm920_switch_mm) +#ifdef CONFIG_MMU mov ip, #0 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache @@ -337,6 +341,7 @@ ENTRY(cpu_arm920_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 /* @@ -346,6 +351,7 @@ ENTRY(cpu_arm920_switch_mm) */ .align 5 ENTRY(cpu_arm920_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 @@ -372,6 +378,7 @@ ENTRY(cpu_arm920_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 /* CONFIG_MMU */ mov pc, lr __INIT @@ -381,7 +388,9 @@ __arm920_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 mrc p15, 0, r0, c1, c0 @ get control register v4 ldr r5, arm920_cr1_clear bic r0, r0, r5 -- cgit v1.2.3