2014-10-31 15:23:26

by Michal Simek

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Subject: Re: Microblaze arch/microblaze/kernel/head.S: redundant code?

Hi,

On 10/31/2014 04:15 PM, Adrian McMenamin wrote:
> Looking at this code at line 78 (in 3.17 kernel) it has:
>
> mfs r1, rmsr
> msrclr r8, 0
> cmpu r8, r8, r1
>
> But as far as I can see the result of that comparison is never used - the
> comments state it is to test if the msrclr instruction is enabled.

r8 is used when machine_early_init() is called.
r8 is 4th register which is used for passing args based on Microblaze
reference manual.

Thanks,
Michal

--
Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91
w: http://www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel - Microblaze cpu - http://www.monstr.eu/fdt/
Maintainer of Linux kernel - Xilinx Zynq ARM architecture
Microblaze U-BOOT custodian and responsible for u-boot arm zynq platform



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