From mboxrd@z Thu Jan  1 00:00:00 1970
From: See, Chin Liang <chin.liang.see@intel.com>
Date: Thu, 31 May 2018 09:52:13 +0000
Subject: [U-Boot] [PATCH] ARM: socfpga: Assure correct ACTLR
	configuration
In-Reply-To: <20180529163933.29665-1-marex@denx.de>
References: <20180529163933.29665-1-marex@denx.de>
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To: u-boot@lists.denx.de

On Tue, 2018-05-29 at 18:39 +0200, Marek Vasut wrote:
> Make sure the ARM ACTLR register has correct configuration, otherwise
> the Linux kernel refuses to boot. In particular, the "Write Full Line
> of Zeroes" bit must be cleared.
> 
> Signed-off-by: Marek Vasut <marex@denx.de>
> Cc: Chin Liang See <chin.liang.see@intel.com>
> Cc: Dinh Nguyen <dinguyen@kernel.org>
> ---
> NOTE: This gem was well hidden in the Altera U-Boot fork and is
> really needed.
>       What is not entirely clear to me is WHY ? So why is this needed
> ?

I vaguely recall it's related to HW constrain. And check back the
downstream U-Boot, actually we need to set the bit instead clearing
it. https://github.com/altera-opensource/u-boot-socfpga/blob/socfpga_v2
014.10_arria10_bringup/arch/arm/cpu/armv7/socfpga_arria10/pl310.c

Thanks
Chin Liang

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