[U-Boot-Users] board porting question

Xuezhang Dong xdong at broadcom.com
Fri Jan 13 03:39:48 CET 2006

I figure out this problem, it is due to the code in start.S set up
Align, so the data read from 16-bit-bus throught ldrb will revert in
big-endian case, and OMAP is little-endian, so they are OK.

	 * 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

	 * Go setup Memory and board specific bits prior to relocation.
	mov	ip, lr		/* perserve link reg across call */
	bl	platformsetup	/* go setup pll,mux,memory */
	mov	lr, ip		/* restore link */
	mov	pc, lr		/* back to my caller */

I was debugging the ns16550 (serial driver), and find out that my serial
port is not logically as same as theirs. I was assume that UART is very
standard, is it true? Any suggestion of other serial drive I can try?


-----Original Message-----
From: wd at denx.de [mailto:wd at denx.de] 
Sent: Thursday, January 12, 2006 5:04 PM
To: Xuezhang Dong
Cc: u-boot-users at lists.sourceforge.net
Subject: Re: [U-Boot-Users] board porting question

In message
<54AD0F12E08D1541B826BE97C98F99F11C29CE at NT-SJCA-0751.brcm.ad.broadcom.co
m> you wrote:
> Thanks for the reply and my appology for the HTML format, I thought 
> mail server will convert it. Never mind, it wonot happened again.


> I was using the latest toolchain from snapgear:
> ARM/XSCALE - arm-linux-tools-20051123.tar.gz
> And I supplied the compiler with -mbigarm parameter.
> Any idea how I can verify/debug this problem?

Attach your BDI2000 and fire up GDB?

Best regards,

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Microsoft Multimedia:
You have nice graphics, sound and animations when the system crashes.

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