From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 39F9DC433E2 for ; Fri, 4 Sep 2020 23:26:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EEE5C2078E for ; Fri, 4 Sep 2020 23:26:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728330AbgIDX0g (ORCPT ); Fri, 4 Sep 2020 19:26:36 -0400 Received: from kvm5.telegraphics.com.au ([98.124.60.144]:34886 "EHLO kvm5.telegraphics.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728273AbgIDX03 (ORCPT ); Fri, 4 Sep 2020 19:26:29 -0400 Received: by kvm5.telegraphics.com.au (Postfix, from userid 502) id 050452ACD7; Fri, 4 Sep 2020 19:26:27 -0400 (EDT) To: Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Message-Id: In-Reply-To: References: From: Finn Thain Subject: [PATCH 4/5] powerpc/tau: Check processor type before enabling TAU interrupt Date: Sat, 05 Sep 2020 09:02:20 +1000 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org According to Freescale's documentation, MPC74XX processors have an erratum that prevents the TAU interrupt from working, so don't try to use it when running on those processors. Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2") Tested-by: Stan Johnson Signed-off-by: Finn Thain --- arch/powerpc/kernel/tau_6xx.c | 33 ++++++++++++++------------------- arch/powerpc/platforms/Kconfig | 5 ++--- 2 files changed, 16 insertions(+), 22 deletions(-) diff --git a/arch/powerpc/kernel/tau_6xx.c b/arch/powerpc/kernel/tau_6xx.c index b8d7e7d498e0a..614b5b272d9c6 100644 --- a/arch/powerpc/kernel/tau_6xx.c +++ b/arch/powerpc/kernel/tau_6xx.c @@ -40,6 +40,8 @@ static struct tau_temp unsigned char grew; } tau[NR_CPUS]; +static bool tau_int_enable; + #undef DEBUG /* TODO: put these in a /proc interface, with some sanity checks, and maybe @@ -54,22 +56,13 @@ static struct tau_temp static void set_thresholds(unsigned long cpu) { -#ifdef CONFIG_TAU_INT - /* - * setup THRM1, - * threshold, valid bit, enable interrupts, interrupt when below threshold - */ - mtspr(SPRN_THRM1, THRM1_THRES(tau[cpu].low) | THRM1_V | THRM1_TIE | THRM1_TID); + u32 maybe_tie = tau_int_enable ? THRM1_TIE : 0; - /* setup THRM2, - * threshold, valid bit, enable interrupts, interrupt when above threshold - */ - mtspr (SPRN_THRM2, THRM1_THRES(tau[cpu].high) | THRM1_V | THRM1_TIE); -#else - /* same thing but don't enable interrupts */ - mtspr(SPRN_THRM1, THRM1_THRES(tau[cpu].low) | THRM1_V | THRM1_TID); - mtspr(SPRN_THRM2, THRM1_THRES(tau[cpu].high) | THRM1_V); -#endif + /* setup THRM1, threshold, valid bit, interrupt when below threshold */ + mtspr(SPRN_THRM1, THRM1_THRES(tau[cpu].low) | THRM1_V | maybe_tie | THRM1_TID); + + /* setup THRM2, threshold, valid bit, interrupt when above threshold */ + mtspr(SPRN_THRM2, THRM1_THRES(tau[cpu].high) | THRM1_V | maybe_tie); } static void TAUupdate(int cpu) @@ -142,9 +135,8 @@ static void tau_timeout(void * info) local_irq_save(flags); cpu = smp_processor_id(); -#ifndef CONFIG_TAU_INT - TAUupdate(cpu); -#endif + if (!tau_int_enable) + TAUupdate(cpu); size = tau[cpu].high - tau[cpu].low; if (size > min_window && ! tau[cpu].grew) { @@ -225,6 +217,9 @@ static int __init TAU_init(void) return 1; } + tau_int_enable = IS_ENABLED(CONFIG_TAU_INT) && + !strcmp(cur_cpu_spec->platform, "ppc750"); + tau_workq = alloc_workqueue("tau", WQ_UNBOUND, 1, 0); if (!tau_workq) return -ENOMEM; @@ -234,7 +229,7 @@ static int __init TAU_init(void) queue_work(tau_workq, &tau_work); pr_info("Thermal assist unit using %s, shrink_timer: %d ms\n", - IS_ENABLED(CONFIG_TAU_INT) ? "interrupts" : "workqueue", shrink_timer); + tau_int_enable ? "interrupts" : "workqueue", shrink_timer); tau_initialized = 1; return 0; diff --git a/arch/powerpc/platforms/Kconfig b/arch/powerpc/platforms/Kconfig index fb7515b4fa9c6..9fe36f0b54c1a 100644 --- a/arch/powerpc/platforms/Kconfig +++ b/arch/powerpc/platforms/Kconfig @@ -223,9 +223,8 @@ config TAU temperature within 2-4 degrees Celsius. This option shows the current on-die temperature in /proc/cpuinfo if the cpu supports it. - Unfortunately, on some chip revisions, this sensor is very inaccurate - and in many cases, does not work at all, so don't assume the cpu - temp is actually what /proc/cpuinfo says it is. + Unfortunately, this sensor is very inaccurate when uncalibrated, so + don't assume the cpu temp is actually what /proc/cpuinfo says it is. config TAU_INT bool "Interrupt driven TAU driver (DANGEROUS)" -- 2.26.2