[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-sa1100.S b/arch/arm/mm/proc-sa1100.S
index 777ad99..0a2107a 100644
--- a/arch/arm/mm/proc-sa1100.S
+++ b/arch/arm/mm/proc-sa1100.S
@@ -2,6 +2,7 @@
* linux/arch/arm/mm/proc-sa1100.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
@@ -77,7 +78,9 @@
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........
@@ -142,12 +145,16 @@
*/
.align 5
ENTRY(cpu_sa1100_switch_mm)
+#ifdef CONFIG_MMU
str lr, [sp, #-4]!
bl v4wb_flush_kern_cache_all @ clears IP
mcr p15, 0, ip, c9, c0, 0 @ invalidate RB
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_sa1100_set_pte(ptep, pte)
@@ -156,6 +163,7 @@
*/
.align 5
ENTRY(cpu_sa1100_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
@@ -177,6 +185,7 @@
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
@@ -186,7 +195,9 @@
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, sa1100_cr1_clear
bic r0, r0, r5