From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 42GZKT2xxTzF3P5 for ; Fri, 21 Sep 2018 10:31:37 +1000 (AEST) Message-ID: <1537489893.7689.38.camel@redhat.com> Subject: Re: [PATCH ppc-next] powerpc/fsl-booke: don't load early TLB at once From: Scott Wood To: David Lamparter , linuxppc-dev@lists.ozlabs.org Cc: Scott Wood , York Sun Date: Thu, 20 Sep 2018 19:31:33 -0500 In-Reply-To: <20180920224856.GJ487685@eidolon.nox.tf> References: <20180920224856.GJ487685@eidolon.nox.tf> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, 2018-09-21 at 00:48 +0200, David Lamparter wrote: > This is a *partial* revert of "powerpc/85xx: Load all early TLB entries > at once" (d9e1831a420267a7ced708bb259d65b0a3c0344d.) > > My dusty old P4080DS just completely fails to boot (no output at all) > without this revert. I have no clue what's going on here, I just > bisected it down and since it looks like an optimization to me I just > reverted it - and voilá, the P4080 boots again. It's not an optimization; it was required to get kdump working, at least for certain choices of crash kernel location. I just tried booting a 32- bit kernel and did not see this problem -- but I don't have access to a p4080ds anymore. I tried with qemu e500mc, and also running a 32-bit kernel on e6500 (needs a tiny change to get past SMP init, since 32-bit isn't really supported on e6500, but you do get output even without that). Do you have a JTAG that can be used to find out where it's hanging? If not, I can try to get early debug working (needs an early IOMMU mapping). York, can you try booting the latest kernel on p4080ds? -Scott