Re: [PATCH ppc-next] powerpc/fsl-booke: don't load early TLB at once

On 09/21/2018 10:47 AM, Scott Wood wrote:=0A=

On Fri, 2018-09-21 at 17:40 +0000, York Sun wrote:=0A=

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On 09/20/2018 05:31 PM, Scott Wood wrote:=0A=

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On Fri, 2018-09-21 at 00:48 +0200, David Lamparter wrote:=0A=

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This is a *partial* revert of "powerpc/85xx: Load all early TLB entrie=

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at once" (d9e1831a420267a7ced708bb259d65b0a3c0344d.)=0A=
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My dusty old P4080DS just completely fails to boot (no output at all)=

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without this revert.  I have no clue what's going on here, I just=0A=
bisected it down and since it looks like an optimization to me I just=

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reverted it - and voil=E1, the P4080 boots again.=0A=

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It's not an optimization; it was required to get kdump working, at leas=

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for certain choices of crash kernel location.  I just tried booting a 3=

2-=0A=

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bit kernel and did not see this problem -- but I don't have access to a=

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p4080ds anymore.  I tried with qemu e500mc, and also running a 32-bit=

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kernel on e6500 (needs a tiny change to get past SMP init, since 32-bit=

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isn't really supported on e6500, but you do get output even without tha=

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Do you have a JTAG that can be used to find out where it's hanging?  If=

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not, I can try to get early debug working (needs an early IOMMU mapping=

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York, can you try booting the latest kernel on p4080ds?=0A=
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Scott,=0A=
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I haven't tried P4080DS for a long time. What defconfig do you use for=

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this board? I tried latest master branch (commit a27fb6d983c7b5) with=0A=
corenet_basic_defconfig, it didn't boot up. Kernel has an exception very=

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early (pc ffffae80).=0A=
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However, before I claimed the board, someone booted Linux 4.14.71 on=0A=
this board. I need to track down where the image came from.=0A=

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Use corenet32_smp_defconfig=0A=
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corenet_basic_defconfig is just a fragment used by the makefiles in assem=

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the final config.=0A=
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Thanks for the instruction. Linux comes up OK with corenet32_smp_defconfig.=
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root@p4080ds:~# uname -a=0A=
Linux p4080ds 4.19.0-rc4-00206-ga27fb6d #1 SMP Fri Sep 21 10:56:36 PDT=0A=
2018 ppc GNU/Linux=0A=
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York=0A=
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