[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-arm6_7.S b/arch/arm/mm/proc-arm6_7.S
index 540359b..7a705ed 100644
--- a/arch/arm/mm/proc-arm6_7.S
+++ b/arch/arm/mm/proc-arm6_7.S
@@ -2,6 +2,7 @@
* linux/arch/arm/mm/proc-arm6,7.S
*
* Copyright (C) 1997-2000 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
@@ -199,10 +200,12 @@
*/
ENTRY(cpu_arm6_switch_mm)
ENTRY(cpu_arm7_switch_mm)
+#ifdef CONFIG_MMU
mov r1, #0
mcr p15, 0, r1, c7, c0, 0 @ flush cache
mcr p15, 0, r0, c2, c0, 0 @ update page table ptr
mcr p15, 0, r1, c5, c0, 0 @ flush TLBs
+#endif
mov pc, lr
/*
@@ -214,6 +217,7 @@
.align 5
ENTRY(cpu_arm6_set_pte)
ENTRY(cpu_arm7_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
@@ -232,6 +236,7 @@
movne r2, #0
str r2, [r0] @ hardware version
+#endif /* CONFIG_MMU */
mov pc, lr
/*
@@ -243,7 +248,9 @@
ENTRY(cpu_arm7_reset)
mov r1, #0
mcr p15, 0, r1, c7, c0, 0 @ flush cache
+#ifdef CONFIG_MMU
mcr p15, 0, r1, c5, c0, 0 @ flush TLB
+#endif
mov r1, #0x30
mcr p15, 0, r1, c1, c0, 0 @ turn off MMU etc
mov pc, r0
@@ -253,19 +260,27 @@
.type __arm6_setup, #function
__arm6_setup: mov r0, #0
mcr p15, 0, r0, c7, c0 @ flush caches on v3
+#ifdef CONFIG_MMU
mcr p15, 0, r0, c5, c0 @ flush TLBs on v3
mov r0, #0x3d @ . ..RS BLDP WCAM
orr r0, r0, #0x100 @ . ..01 0011 1101
+#else
+ mov r0, #0x3c @ . ..RS BLDP WCA.
+#endif
mov pc, lr
.size __arm6_setup, . - __arm6_setup
.type __arm7_setup, #function
__arm7_setup: mov r0, #0
mcr p15, 0, r0, c7, c0 @ flush caches on v3
+#ifdef CONFIG_MMU
mcr p15, 0, r0, c5, c0 @ flush TLBs on v3
mcr p15, 0, r0, c3, c0 @ load domain access register
mov r0, #0x7d @ . ..RS BLDP WCAM
orr r0, r0, #0x100 @ . ..01 0111 1101
+#else
+ mov r0, #0x7c @ . ..RS BLDP WCA.
+#endif
mov pc, lr
.size __arm7_setup, . - __arm7_setup