[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 <hyok.choi@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mm/proc-arm1026.S b/arch/arm/mm/proc-arm1026.S
index 148c111..abe850c 100644
--- a/arch/arm/mm/proc-arm1026.S
+++ b/arch/arm/mm/proc-arm1026.S
@@ -3,6 +3,7 @@
*
* Copyright (C) 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
@@ -90,7 +91,9 @@
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........
@@ -327,6 +330,7 @@
*/
.align 5
ENTRY(cpu_arm1026_switch_mm)
+#ifdef CONFIG_MMU
mov r1, #0
#ifndef CONFIG_CPU_DCACHE_DISABLE
1: mrc p15, 0, r15, c7, c14, 3 @ test, clean, invalidate
@@ -338,6 +342,7 @@
mcr p15, 0, r1, c7, c10, 4 @ drain WB
mcr p15, 0, r0, c2, c0, 0 @ load page table pointer
mcr p15, 0, r1, c8, c7, 0 @ invalidate I & D TLBs
+#endif
mov pc, lr
/*
@@ -347,6 +352,7 @@
*/
.align 5
ENTRY(cpu_arm1026_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
@@ -374,6 +380,7 @@
#ifndef CONFIG_CPU_DCACHE_DISABLE
mcr p15, 0, r0, c7, c10, 1 @ clean D entry
#endif
+#endif /* CONFIG_MMU */
mov pc, lr
@@ -384,8 +391,10 @@
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
mcr p15, 0, r4, c2, c0 @ load page table pointer
+#endif
#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
mov r0, #4 @ explicitly disable writeback
mcr p15, 7, r0, c15, c0, 0