* [U-Boot] why bic sp, sp, #7 /* 8-byte alignment for ABI compliance */
@ 2013-02-17 9:59 janpharm
2013-02-17 11:30 ` [U-Boot] u-boot recovery mode TigerLiu at viatech.com.cn
2013-02-17 14:04 ` [U-Boot] why bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ Benoît Thébaudeau
0 siblings, 2 replies; 6+ messages in thread
From: janpharm @ 2013-02-17 9:59 UTC (permalink / raw)
To: u-boot
Hi All,
After searching via google,I still can not find the hint for
I understand the function of bic command, but did not understand :
why "bic sp, sp, #7" can be implied for "8-byte alignment for ABI
compliance" ?
can someone offer some example?
thanks!
--
View this message in context: http://u-boot.10912.n7.nabble.com/why-bic-sp-sp-7-8-byte-alignment-for-ABI-compliance-tp147472.html
Sent from the U-Boot mailing list archive at Nabble.com.
^ permalink raw reply [flat|nested] 6+ messages in thread
* [U-Boot] u-boot recovery mode
2013-02-17 9:59 [U-Boot] why bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ janpharm
@ 2013-02-17 11:30 ` TigerLiu at viatech.com.cn
2013-02-17 14:34 ` Albert ARIBAUD
2013-02-17 14:04 ` [U-Boot] why bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ Benoît Thébaudeau
1 sibling, 1 reply; 6+ messages in thread
From: TigerLiu at viatech.com.cn @ 2013-02-17 11:30 UTC (permalink / raw)
To: u-boot
Hi, experts:
I found u-boot did not implement a recovery mode in current source code.
Such as:
1. detecting usr pressed some dedicated keys , then going into a
recovery mode.
Why?
Vendor specific?
Best wishes,
^ permalink raw reply [flat|nested] 6+ messages in thread
* [U-Boot] u-boot recovery mode
2013-02-17 11:30 ` [U-Boot] u-boot recovery mode TigerLiu at viatech.com.cn
@ 2013-02-17 14:34 ` Albert ARIBAUD
2013-02-18 1:44 ` TigerLiu at viatech.com.cn
0 siblings, 1 reply; 6+ messages in thread
From: Albert ARIBAUD @ 2013-02-17 14:34 UTC (permalink / raw)
To: u-boot
Hi TigerLiu at viatech.com.cn,
On Sun, 17 Feb 2013 19:30:17 +0800, <TigerLiu@viatech.com.cn> wrote:
> Hi, experts:
> I found u-boot did not implement a recovery mode in current source code.
> Such as:
> 1. detecting usr pressed some dedicated keys , then going into a
> recovery mode.
>
> Why?
> Vendor specific?
Such a mode can be implemented through U-Boot's environment variables
without the need for hard-coding anything.
Amicalement,
--
Albert.
^ permalink raw reply [flat|nested] 6+ messages in thread
* [U-Boot] u-boot recovery mode
2013-02-17 14:34 ` Albert ARIBAUD
@ 2013-02-18 1:44 ` TigerLiu at viatech.com.cn
2013-02-18 7:42 ` Albert ARIBAUD
0 siblings, 1 reply; 6+ messages in thread
From: TigerLiu at viatech.com.cn @ 2013-02-18 1:44 UTC (permalink / raw)
To: u-boot
Hi, Albert:
Thanks for your answer!
So, how to use env variable to implement the recovery mode?
Will who set this env variable?
OS? (if OS wants to go into recovery mode, it will set this env variable)
Best wishes,
-----????-----
???: u-boot-bounces at lists.denx.de [mailto:u-boot-bounces at lists.denx.de] ?? Albert ARIBAUD
????: 2013?2?17? 22:34
???: Tiger Liu
??: u-boot at lists.denx.de
??: Re: [U-Boot] u-boot recovery mode
Hi TigerLiu at viatech.com.cn,
On Sun, 17 Feb 2013 19:30:17 +0800, <TigerLiu@viatech.com.cn> wrote:
> Hi, experts:
> I found u-boot did not implement a recovery mode in current source code.
> Such as:
> 1. detecting usr pressed some dedicated keys , then going into a
> recovery mode.
>
> Why?
> Vendor specific?
Such a mode can be implemented through U-Boot's environment variables
without the need for hard-coding anything.
Amicalement,
--
Albert.
_______________________________________________
U-Boot mailing list
U-Boot at lists.denx.de
http://lists.denx.de/mailman/listinfo/u-boot
^ permalink raw reply [flat|nested] 6+ messages in thread
* [U-Boot] why bic sp, sp, #7 /* 8-byte alignment for ABI compliance */
2013-02-17 9:59 [U-Boot] why bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ janpharm
2013-02-17 11:30 ` [U-Boot] u-boot recovery mode TigerLiu at viatech.com.cn
@ 2013-02-17 14:04 ` Benoît Thébaudeau
1 sibling, 0 replies; 6+ messages in thread
From: Benoît Thébaudeau @ 2013-02-17 14:04 UTC (permalink / raw)
To: u-boot
Hi,
On Sunday, February 17, 2013 10:59:10 AM, janpharm wrote:
> Hi All,
>
> After searching via google,I still can not find the hint for
>
> I understand the function of bic command,
http://infocenter.arm.com/help/topic/com.arm.doc.qrc0001l/QRC0001_UAL.pdf
Simple bit clear with bit-mask.
> but did not understand :
>
> why "bic sp, sp, #7" can be implied for "8-byte alignment for ABI
> compliance" ?
http://infocenter.arm.com/help/topic/com.arm.doc.qrc0001l/QRC0001_UAL.pdf
5.2.1.2.
SP has to be double-word (64-bit, 8-byte) aligned, so since this is an
expand-down stack, its lower 3 bits have to be cleared in order to make
it a multiple of 8.
> can someone offer some example?
http://git.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=blob;f=arch/arm/lib/crt0.S;h=4f60958b1dbf1782863cebd7ffe884733a452b26;hb=HEAD#l110
Best regards,
Beno?t
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2013-02-18 7:42 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-02-17 9:59 [U-Boot] why bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ janpharm
2013-02-17 11:30 ` [U-Boot] u-boot recovery mode TigerLiu at viatech.com.cn
2013-02-17 14:34 ` Albert ARIBAUD
2013-02-18 1:44 ` TigerLiu at viatech.com.cn
2013-02-18 7:42 ` Albert ARIBAUD
2013-02-17 14:04 ` [U-Boot] why bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ Benoît Thébaudeau
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