[U-Boot] [PATCH 1/2] MX28: Drop the cp15 reconfiguration from SPL

Marek Vasut marex at denx.de
Mon Aug 6 23:34:54 CEST 2012


The SPL doesn't need the CP15 reconfiguration, as that's what the
BootROM does for us already. Moreover, when the CP15 is reconfigured
and the code returns control to BootROM, the USB boot works no more.

Remove the code and allow [1] to work properly as well.

[1] http://git.bfuser.eu/?p=marex/mxsldr.git;a=summary

Signed-off-by: Marek Vasut <marex at denx.de>
Cc: Stefano Babic <sbabic at denx.de>
Cc: Fabio Estevam <fabio.estevam at freescale.com>
---
 arch/arm/cpu/arm926ejs/mx28/start.S |   42 -----------------------------------
 1 file changed, 42 deletions(-)

diff --git a/arch/arm/cpu/arm926ejs/mx28/start.S b/arch/arm/cpu/arm926ejs/mx28/start.S
index e572b78..7ccd337 100644
--- a/arch/arm/cpu/arm926ejs/mx28/start.S
+++ b/arch/arm/cpu/arm926ejs/mx28/start.S
@@ -180,14 +180,6 @@ _reset:
 	orr	r0,r0,#0xd3
 	msr	cpsr,r0
 
-	/*
-	 * we do sys-critical inits only at reboot,
-	 * not when booting from ram!
-	 */
-#ifndef CONFIG_SKIP_LOWLEVEL_INIT
-	bl	cpu_init_crit
-#endif
-
 	bl	board_init_ll
 
 	/*
@@ -207,40 +199,6 @@ _reset:
 	pop	{r0-r12,r14}
 	bx	lr
 
-/*
- *************************************************************************
- *
- * CPU_init_critical registers
- *
- * setup important registers
- * setup memory timing
- *
- *************************************************************************
- */
-#ifndef CONFIG_SKIP_LOWLEVEL_INIT
-cpu_init_crit:
-	/*
-	 * flush v4 I/D caches
-	 */
-	mov	r0, #0
-	mcr	p15, 0, r0, c7, c7, 0	/* flush v3/v4 cache */
-	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */
-
-	/*
-	 * disable MMU stuff and caches
-	 */
-	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
-
-	mov	pc, lr		/* back to my caller */
-
-	.align	5
-#endif /* CONFIG_SKIP_LOWLEVEL_INIT */
-
 _hang:
 	ldr	sp, _TEXT_BASE			/* switch to abort stack */
 1:
-- 
1.7.10.4



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