[U-Boot] [PATCH v8 29/31] arm1176: Remove unused MMU setup from start.S

Benoît Thébaudeau benoit.thebaudeau at advansee.com
Fri Mar 1 13:10:38 CET 2013


Following the removal of the smdk6400 board, the MMU setup code in
arm1176/start.S becomes unused, so move it to scrapyard. It will still be
possible to restore it later from the Git history if necessary, in which case it
should be moved out from the relocate_code() function.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau at advansee.com>
---
Changes in v8:
 - New patch.

Changes in v7: None
Changes in v6: None
Changes in v5: None
Changes in v4: None
Changes in v3: None
Changes in v2: None

 arch/arm/cpu/arm1176/start.S |   91 +-----------------------------------------
 1 file changed, 1 insertion(+), 90 deletions(-)

diff --git a/arch/arm/cpu/arm1176/start.S b/arch/arm/cpu/arm1176/start.S
index b3c686a..18ac8d5 100644
--- a/arch/arm/cpu/arm1176/start.S
+++ b/arch/arm/cpu/arm1176/start.S
@@ -33,11 +33,8 @@
 #include <asm-offsets.h>
 #include <config.h>
 #include <version.h>
-#ifdef CONFIG_ENABLE_MMU
-#include <asm/proc/domain.h>
-#endif
 
-#if !defined(CONFIG_ENABLE_MMU) && !defined(CONFIG_SYS_PHY_UBOOT_BASE)
+#ifndef CONFIG_SYS_PHY_UBOOT_BASE
 #define CONFIG_SYS_PHY_UBOOT_BASE	CONFIG_SYS_UBOOT_BASE
 #endif
 
@@ -105,14 +102,6 @@ _TEXT_BASE:
 #endif
 
 /*
- * Below variable is very important because we use MMU in U-Boot.
- * Without it, we cannot run code correctly before MMU is ON.
- * by scsuh.
- */
-_TEXT_PHY_BASE:
-	.word	CONFIG_SYS_PHY_UBOOT_BASE
-
-/*
  * These are defined in the board-specific linker script.
  * Subtracting _start from them lets the linker put their
  * relative position in the executable instead of leaving
@@ -298,44 +287,6 @@ fixnext:
 	blo	fixloop
 #endif
 
-#ifdef CONFIG_ENABLE_MMU
-enable_mmu:
-	/* enable domain access */
-	ldr	r5, =0x0000ffff
-	mcr	p15, 0, r5, c3, c0, 0	/* load domain access register */
-
-	/* Set the TTB register */
-	ldr	r0, _mmu_table_base
-	ldr	r1, =CONFIG_SYS_PHY_UBOOT_BASE
-	ldr	r2, =0xfff00000
-	bic	r0, r0, r2
-	orr	r1, r0, r1
-	mcr	p15, 0, r1, c2, c0, 0
-
-	/* Enable the MMU */
-	mrc	p15, 0, r0, c1, c0, 0
-	orr	r0, r0, #1		/* Set CR_M to enable MMU */
-
-	/* Prepare to enable the MMU */
-	adr	r1, skip_hw_init
-	and	r1, r1, #0x3fc
-	ldr	r2, _TEXT_BASE
-	ldr	r3, =0xfff00000
-	and	r2, r2, r3
-	orr	r2, r2, r1
-	b	mmu_enable
-
-	.align 5
-	/* Run in a single cache-line */
-mmu_enable:
-
-	mcr	p15, 0, r0, c1, c0, 0
-	nop
-	nop
-	mov	pc, r2
-skip_hw_init:
-#endif
-
 relocate_done:
 
 	bx	lr
@@ -347,11 +298,6 @@ _rel_dyn_end_ofs:
 _dynsym_start_ofs:
 	.word __dynsym_start - _start
 
-#ifdef CONFIG_ENABLE_MMU
-_mmu_table_base:
-	.word mmu_table
-#endif
-
 	.globl	c_runtime_cpu_setup
 c_runtime_cpu_setup:
 
@@ -359,41 +305,6 @@ c_runtime_cpu_setup:
 
 #ifndef CONFIG_SPL_BUILD
 /*
- * we assume that cache operation is done before. (eg. cleanup_before_linux())
- * actually, we don't need to do anything about cache if not use d-cache in
- * U-Boot. So, in this function we clean only MMU. by scsuh
- *
- * void	theLastJump(void *kernel, int arch_num, uint boot_params);
- */
-#ifdef CONFIG_ENABLE_MMU
-	.globl theLastJump
-theLastJump:
-	mov	r9, r0
-	ldr	r3, =0xfff00000
-	ldr	r4, _TEXT_PHY_BASE
-	adr	r5, phy_last_jump
-	bic	r5, r5, r3
-	orr	r5, r5, r4
-	mov	pc, r5
-phy_last_jump:
-	/*
-	 * disable MMU stuff
-	 */
-	mrc	p15, 0, r0, c1, c0, 0
-	bic	r0, r0, #0x00002300	/* clear bits 13, 9:8 (--V- --RS) */
-	bic	r0, r0, #0x00000087	/* clear bits 7, 2:0 (B--- -CAM) */
-	orr	r0, r0, #0x00000002	/* set bit 2 (A) Align */
-	orr	r0, r0, #0x00001000	/* set bit 12 (I) I-Cache */
-	mcr	p15, 0, r0, c1, c0, 0
-
-	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */
-
-	mov	r0, #0
-	mov	pc, r9
-#endif
-
-
-/*
  *************************************************************************
  *
  * Interrupt handling
-- 
1.7.10.4



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