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From: Anton Blanchard <anton@samba•org>
To: Samuel Mendoza-Jonas <sam.mj@au1•ibm.com>
Cc: linuxppc-dev@ozlabs•org
Subject: Re: [kexec-lite PATCH] trampoline: Reset primary cpu endian to big-endian
Date: Wed, 8 Jul 2015 11:56:32 +1000	[thread overview]
Message-ID: <20150708115632.725120f1@kryten> (raw)
In-Reply-To: <1436318742-13490-1-git-send-email-sam.mj@au1.ibm.com>

Hi Sam,

> Older big-endian ppc64 kernels don't include the FIXUP_ENDIAN check,
> meaning if we kexec from a little-endian kernel the target kernel will
> fail to boot.
> Returning to big-endian before we enter the target kernel ensures that
> the target kernel can boot whether or not it includes FIXUP_ENDIAN.

Thanks!

I wonder if we can do something simpler, and always enter via rfid.
Avoids the need for the endian trampoline. Something like:

  	mtsrr0	r4

	mfmsr	r5
	clrrdi	r5,r5,1 	/* Clear MSR_LE */
	mtsrr1	r5

	li	r5,0

	rfid

Anton

  reply	other threads:[~2015-07-08  1:56 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-07-08  1:25 [kexec-lite PATCH] trampoline: Reset primary cpu endian to big-endian Samuel Mendoza-Jonas
2015-07-08  1:56 ` Anton Blanchard [this message]
2015-07-08  3:11   ` Samuel Mendoza-Jonas

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