[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>

[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>
d090ddda · Hyok S. Choi · Russell King · a4f7e763 · d090ddda · d090ddda
Commit d090ddda authored Jun 28, 2006 by Hyok S. Choi Committed by Russell King Jun 28, 2006
13 changed files
--- a/arch/arm/mm/proc-arm1020.S
+++ b/arch/arm/mm/proc-arm1020.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
@@ -101,7 +102,9 @@ ENTRY(cpu_arm1020_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........
@@ -359,6 +362,7 @@ ENTRY(cpu_arm1020_dcache_clean_area)
 */
 	.align	5
 ENTRY(cpu_arm1020_switch_mm)
+#ifdef CONFIG_MMU
 #ifndef CONFIG_CPU_DCACHE_DISABLE
 	mcr	p15, 0, r3, c7, c10, 4
 	mov	r1, #0xF			@ 16 segments
@@ -383,6 +387,7 @@ ENTRY(cpu_arm1020_switch_mm)
 	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 /* CONFIG_MMU */
 	mov	pc, lr
 /*
@@ -392,6 +397,7 @@ ENTRY(cpu_arm1020_switch_mm)
 */
 	.align	5
 ENTRY(cpu_arm1020_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
@@ -421,6 +427,7 @@ ENTRY(cpu_arm1020_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
@@ -430,7 +437,9 @@ __arm1020_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, arm1020_cr1_clear
 	bic	r0, r0, r5

--- a/arch/arm/mm/proc-arm1020e.S
+++ b/arch/arm/mm/proc-arm1020e.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
@@ -101,7 +102,9 @@ ENTRY(cpu_arm1020e_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........
@@ -344,6 +347,7 @@ ENTRY(cpu_arm1020e_dcache_clean_area)
 */
 	.align	5
 ENTRY(cpu_arm1020e_switch_mm)
+#ifdef CONFIG_MMU
 #ifndef CONFIG_CPU_DCACHE_DISABLE
 	mcr	p15, 0, r3, c7, c10, 4
 	mov	r1, #0xF			@ 16 segments
@@ -367,6 +371,7 @@ ENTRY(cpu_arm1020e_switch_mm)
 	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
 /*
@@ -376,6 +381,7 @@ ENTRY(cpu_arm1020e_switch_mm)
 */
 	.align	5
 ENTRY(cpu_arm1020e_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
@@ -403,6 +409,7 @@ ENTRY(cpu_arm1020e_set_pte)
 #ifndef CONFIG_CPU_DCACHE_DISABLE
 	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
 #endif
+#endif /* CONFIG_MMU */
 	mov	pc, lr
 	__INIT
@@ -412,7 +419,9 @@ __arm1020e_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, arm1020e_cr1_clear
 	bic	r0, r0, r5

--- a/arch/arm/mm/proc-arm1022.S
+++ b/arch/arm/mm/proc-arm1022.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 @@ ENTRY(cpu_arm1022_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........
@@ -333,6 +336,7 @@ ENTRY(cpu_arm1022_dcache_clean_area)
 */
 	.align	5
 ENTRY(cpu_arm1022_switch_mm)
+#ifdef CONFIG_MMU
 #ifndef CONFIG_CPU_DCACHE_DISABLE
 	mov	r1, #(CACHE_DSEGMENTS - 1) << 5	@ 16 segments
 1:	orr	r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
@@ -349,6 +353,7 @@ ENTRY(cpu_arm1022_switch_mm)
 	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
 /*
@@ -358,6 +363,7 @@ ENTRY(cpu_arm1022_switch_mm)
 */
 	.align	5
 ENTRY(cpu_arm1022_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
@@ -385,6 +391,7 @@ ENTRY(cpu_arm1022_set_pte)
 #ifndef CONFIG_CPU_DCACHE_DISABLE
 	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
 #endif
+#endif /* CONFIG_MMU */
 	mov	pc, lr
 	__INIT
@@ -394,7 +401,9 @@ __arm1022_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, arm1022_cr1_clear
 	bic	r0, r0, r5

--- 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 @@ ENTRY(cpu_arm1026_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........
@@ -327,6 +330,7 @@ ENTRY(cpu_arm1026_dcache_clean_area)
 */
 	.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 @@ ENTRY(cpu_arm1026_switch_mm)
 	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 @@ ENTRY(cpu_arm1026_switch_mm)
 */
 	.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 @@ ENTRY(cpu_arm1026_set_pte)
 #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 @@ __arm1026_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
 	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

--- 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_arm7_do_idle)
 */
 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 @@ ENTRY(cpu_arm7_switch_mm)
 		.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 @@ ENTRY(cpu_arm7_set_pte)
 		movne	r2, #0
 		str	r2, [r0]			@ hardware version
+#endif /* CONFIG_MMU */
 		mov	pc, lr
 /*
@@ -243,7 +248,9 @@ ENTRY(cpu_arm6_reset)
 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 @@ ENTRY(cpu_arm7_reset)
 		.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

--- a/arch/arm/mm/proc-arm720.S
+++ b/arch/arm/mm/proc-arm720.S
@@ -4,6 +4,7 @@
 *  Copyright (C) 2000 Steve Hill (sjhill@cotw.com)
 *                     Rob Scott (rscott@mtrob.fdns.net)
 *  Copyright (C) 2000 ARM Limited, Deep Blue Solutions Ltd.
+ *  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
@@ -29,6 +30,7 @@
 *			out of 'proc-arm6,7.S' per RMK discussion
 *   07-25-2000 SJH	Added idle function.
 *   08-25-2000	DBS	Updated for integration of ARM Ltd version.
+ *   04-20-2004 HSC	modified for non-paged memory management mode.
 */
 #include <linux/linkage.h>
 #include <linux/init.h>
@@ -75,10 +77,12 @@ ENTRY(cpu_arm720_do_idle)
 *	     the new.
 */
 ENTRY(cpu_arm720_switch_mm)
+#ifdef CONFIG_MMU
 		mov	r1, #0
 		mcr	p15, 0, r1, c7, c7, 0		@ invalidate cache
 		mcr	p15, 0, r0, c2, c0, 0		@ update page table ptr
 		mcr	p15, 0, r1, c8, c7, 0		@ flush TLB (v4)
+#endif
 		mov	pc, lr
 /*
@@ -89,6 +93,7 @@ ENTRY(cpu_arm720_switch_mm)
 */
 		.align	5
 ENTRY(cpu_arm720_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
@@ -107,6 +112,7 @@ ENTRY(cpu_arm720_set_pte)
 		movne	r2, #0
 		str	r2, [r0]			@ hardware version
+#endif
 		mov	pc, lr
 /*
@@ -117,7 +123,9 @@ ENTRY(cpu_arm720_set_pte)
 ENTRY(cpu_arm720_reset)
 		mov	ip, #0
 		mcr	p15, 0, ip, c7, c7, 0		@ invalidate cache
+#ifdef CONFIG_MMU
 		mcr	p15, 0, ip, c8, c7, 0		@ flush TLB (v4)
+#endif
 		mrc	p15, 0, ip, c1, c0, 0		@ get ctrl register
 		bic	ip, ip, #0x000f			@ ............wcam
 		bic	ip, ip, #0x2100			@ ..v....s........
@@ -130,7 +138,9 @@ ENTRY(cpu_arm720_reset)
 __arm710_setup:
 	mov	r0, #0
 	mcr	p15, 0, r0, c7, c7, 0		@ invalidate caches
+#ifdef CONFIG_MMU
 	mcr	p15, 0, r0, c8, c7, 0		@ flush TLB (v4)
+#endif
 	mrc	p15, 0, r0, c1, c0		@ get control register
 	ldr	r5, arm710_cr1_clear
 	bic	r0, r0, r5
@@ -156,7 +166,9 @@ arm710_cr1_set:
 __arm720_setup:
 	mov	r0, #0
 	mcr	p15, 0, r0, c7, c7, 0		@ invalidate caches
+#ifdef CONFIG_MMU
 	mcr	p15, 0, r0, c8, c7, 0		@ flush TLB (v4)
+#endif
 	mrc	p15, 0, r0, c1, c0		@ get control register
 	ldr	r5, arm720_cr1_clear
 	bic	r0, r0, r5

--- 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

--- a/arch/arm/mm/proc-arm922.S
+++ b/arch/arm/mm/proc-arm922.S
@@ -4,6 +4,7 @@
 *  Copyright (C) 1999,2000 ARM Limited
 *  Copyright (C) 2000 Deep Blue Solutions Ltd.
 *  Copyright (C) 2001 Altera Corporation
+ *  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
@@ -99,7 +100,9 @@ ENTRY(cpu_arm922_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........
@@ -321,6 +324,7 @@ ENTRY(cpu_arm922_dcache_clean_area)
 */
 	.align	5
 ENTRY(cpu_arm922_switch_mm)
+#ifdef CONFIG_MMU
 	mov	ip, #0
 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
 	mcr	p15, 0, ip, c7, c6, 0		@ invalidate D cache
@@ -341,6 +345,7 @@ ENTRY(cpu_arm922_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
 /*
@@ -350,6 +355,7 @@ ENTRY(cpu_arm922_switch_mm)
 */
 	.align	5
 ENTRY(cpu_arm922_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
@@ -376,6 +382,7 @@ ENTRY(cpu_arm922_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
@@ -385,7 +392,9 @@ __arm922_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, arm922_cr1_clear
 	bic	r0, r0, r5

--- 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 <tony@atomide.com>
 *
+ *  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

--- a/arch/arm/mm/proc-arm926.S
+++ b/arch/arm/mm/proc-arm926.S
@@ -3,6 +3,7 @@
 *
 *  Copyright (C) 1999-2001 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
@@ -85,7 +86,9 @@ ENTRY(cpu_arm926_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........
@@ -329,6 +332,7 @@ ENTRY(cpu_arm926_dcache_clean_area)
 */
 	.align	5
 ENTRY(cpu_arm926_switch_mm)
+#ifdef CONFIG_MMU
 	mov	ip, #0
 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
 	mcr	p15, 0, ip, c7, c6, 0		@ invalidate D cache
@@ -341,6 +345,7 @@ ENTRY(cpu_arm926_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
 /*
@@ -350,6 +355,7 @@ ENTRY(cpu_arm926_switch_mm)
 */
 	.align	5
 ENTRY(cpu_arm926_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
@@ -378,6 +384,7 @@ ENTRY(cpu_arm926_set_pte)
 	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
 #endif
 	mcr	p15, 0, r0, c7, c10, 4		@ drain WB
+#endif
 	mov	pc, lr
 	__INIT
@@ -387,7 +394,9 @@ __arm926_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

--- a/arch/arm/mm/proc-sa110.S
+++ b/arch/arm/mm/proc-sa110.S
@@ -2,6 +2,7 @@
 *  linux/arch/arm/mm/proc-sa110.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
@@ -67,7 +68,9 @@ ENTRY(cpu_sa110_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........
@@ -130,11 +133,15 @@ ENTRY(cpu_sa110_dcache_clean_area)
 */
 	.align	5
 ENTRY(cpu_sa110_switch_mm)
+#ifdef CONFIG_MMU
 	str	lr, [sp, #-4]!
 	bl	v4wb_flush_kern_cache_all	@ clears IP
 	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_sa110_set_pte(ptep, pte)
@@ -143,6 +150,7 @@ ENTRY(cpu_sa110_switch_mm)
 */
 	.align	5
 ENTRY(cpu_sa110_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
@@ -164,6 +172,7 @@ ENTRY(cpu_sa110_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
 	mov	pc, lr
 	__INIT
@@ -173,7 +182,9 @@ __sa110_setup:
 	mov	r10, #0
 	mcr	p15, 0, r10, c7, c7		@ invalidate I,D caches on v4
 	mcr	p15, 0, r10, c7, c10, 4		@ drain write buffer on v4
+#ifdef CONFIG_MMU
 	mcr	p15, 0, r10, c8, c7		@ invalidate I,D TLBs on v4
+#endif
 	mrc	p15, 0, r0, c1, c0		@ get control register v4
 	ldr	r5, sa110_cr1_clear
 	bic	r0, r0, r5

--- 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 @@ ENTRY(cpu_sa1100_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........
@@ -142,12 +145,16 @@ ENTRY(cpu_sa1100_dcache_clean_area)
 */
 	.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 @@ ENTRY(cpu_sa1100_switch_mm)
 */
 	.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 @@ ENTRY(cpu_sa1100_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
 	mov	pc, lr
 	__INIT
@@ -186,7 +195,9 @@ __sa1100_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, sa1100_cr1_clear
 	bic	r0, r0, r5

--- a/arch/arm/mm/proc-v6.S
+++ b/arch/arm/mm/proc-v6.S
@@ -2,6 +2,7 @@
 *  linux/arch/arm/mm/proc-v6.S
 *
 *  Copyright (C) 2001 Deep Blue Solutions Ltd.
+ *  Modified by Catalin Marinas for noMMU support
 *
 * 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
@@ -88,6 +89,7 @@ ENTRY(cpu_v6_dcache_clean_area)
 *	- we are not using split page tables
 */
 ENTRY(cpu_v6_switch_mm)
+#ifdef CONFIG_MMU
 	mov	r2, #0
 	ldr	r1, [r1, #MM_CONTEXT_ID]	@ get mm->context.id
 #ifdef CONFIG_SMP
@@ -97,6 +99,7 @@ ENTRY(cpu_v6_switch_mm)
 	mcr	p15, 0, r2, c7, c10, 4		@ drain write buffer
 	mcr	p15, 0, r0, c2, c0, 0		@ set TTB 0
 	mcr	p15, 0, r1, c13, c0, 1		@ set context ID
+#endif
 	mov	pc, lr
 /*
@@ -119,6 +122,7 @@ ENTRY(cpu_v6_switch_mm)
 *	  1111   0   1   1	r/w	r/w
 */
 ENTRY(cpu_v6_set_pte)
+#ifdef CONFIG_MMU
 	str	r1, [r0], #-2048		@ linux version
 	bic	r2, r1, #0x000003f0
@@ -145,6 +149,7 @@ ENTRY(cpu_v6_set_pte)
 	str	r2, [r0]
 	mcr	p15, 0, r0, c7, c10, 1 @ flush_pte
+#endif
 	mov	pc, lr
@@ -194,12 +199,14 @@ __v6_setup:
 	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
 	mcr	p15, 0, r0, c7, c15, 0		@ clean+invalidate cache
 	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
+#ifdef CONFIG_MMU
 	mcr	p15, 0, r0, c8, c7, 0		@ invalidate I + D TLBs
 	mcr	p15, 0, r0, c2, c0, 2		@ TTB control register
 #ifdef CONFIG_SMP
 	orr	r4, r4, #TTB_RGN_WBWA|TTB_S	@ mark PTWs shared, outer cacheable
 #endif
 	mcr	p15, 0, r4, c2, c0, 1		@ load TTB1
+#endif /* CONFIG_MMU */
 #ifdef CONFIG_VFP
 	mrc	p15, 0, r0, c1, c0, 2
 	orr	r0, r0, #(0xf << 20)