From nobody Fri Sep 20 20:25:05 2024 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4C2ABC77B7D for ; Mon, 15 May 2023 20:16:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245283AbjEOUQS (ORCPT ); Mon, 15 May 2023 16:16:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36674 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245265AbjEOUQM (ORCPT ); Mon, 15 May 2023 16:16:12 -0400 Received: from mail-pg1-x535.google.com (mail-pg1-x535.google.com [IPv6:2607:f8b0:4864:20::535]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D00B710C3 for ; Mon, 15 May 2023 13:16:10 -0700 (PDT) Received: by mail-pg1-x535.google.com with SMTP id 41be03b00d2f7-53033a0b473so6603160a12.0 for ; Mon, 15 May 2023 13:16:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1684181770; x=1686773770; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=M3ZxCx5hi3hTfImTlWZJFg7LTzfHGowr1aBuZvBj8Ek=; b=Hbdt9iI0CBNRsRWJDq6LO2fdXD8SaO03ZHaJ8lncZbQVLatn4REqixKNi/L63qD17o HHOoNZBZebHLnkPuM0TGc9DikVIAEVVjUSf5dIZfNglLnIldiCXQvYMyLC6zIJUZi7Rd MuSHzfulUWCXbZfoxjiTNIlH48Va9wDUeEHqg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684181770; x=1686773770; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=M3ZxCx5hi3hTfImTlWZJFg7LTzfHGowr1aBuZvBj8Ek=; b=PK2X1lFyioc8lrBhs3+3Nyjsgg23UJnLpYxo8BkktVbQcq8TlXxdDFEzt9TuqUaLDd 2yf8n6diygVhRz6eM6j6afedlJbFZVWJocUK0MoXPFWPTHQHwI6r+CnQqxZpl54JoTxp jZ7XKbqfwUO3QKRvi4kAUmagmJOb1CZXWiL+pahXQorK8ZFsBUcLJVsQoSRTMYuewHVJ wXTOhLTzCiGcKvzD2elmFkCDLy1ecyHdSp6uk8/uj/7rMD2V0lds+G7MOF1bmUN9CZwM GMc1inf3nvISExm0Sv400nTX5MhLbb6iWeTB0BXvcgTgQqdJi8i9d5p1ak33GaTRV7du xhiQ== X-Gm-Message-State: AC+VfDw/3yl7WFv/2HhY4+3aiHYELf0na7TPkKuhLXnJKLrlnwu5dJZL 0RlLbR7c2ocokGVX4/kjb7YLBA== X-Google-Smtp-Source: ACHHUZ7JpUDHXpHh/owDGu2FwcJeNHDuQ797i/IR9w8uSlN+ZOxln0Gpr8ldwjJ5qvjlGTyjodrCkA== X-Received: by 2002:a05:6a21:7898:b0:101:167d:8472 with SMTP id bf24-20020a056a21789800b00101167d8472mr32063218pzc.26.1684181770297; Mon, 15 May 2023 13:16:10 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:9d:2:9f33:9d98:277a:d4cd]) by smtp.gmail.com with ESMTPSA id a19-20020a62bd13000000b0063f0c9eadc7sm7981411pff.200.2023.05.15.13.16.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 May 2023 13:16:09 -0700 (PDT) From: Douglas Anderson To: Marc Zyngier , Thomas Gleixner , Rob Herring , Krzysztof Kozlowski , Matthias Brugger Cc: devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Allen-KH Cheng , linux-mediatek@lists.infradead.org, Eddie Huang , Hsin-Hsiung Wang , AngeloGioacchino Del Regno , wenst@chromium.org, yidilin@chromium.org, Tinghan Shen , jwerner@chromium.org, Weiyi Lu , Ben Ho , Seiya Wang , Douglas Anderson , linux-kernel@vger.kernel.org Subject: [PATCH v2 2/5] irqchip/gic-v3: Disable pseudo NMIs on Mediatek devices w/ firmware issues Date: Mon, 15 May 2023 13:13:51 -0700 Message-ID: <20230515131353.v2.2.I88dc0a0eb1d9d537de61604cd8994ecc55c0cac1@changeid> X-Mailer: git-send-email 2.40.1.606.ga4b1b128d6-goog In-Reply-To: <20230515131353.v2.cover@dianders> References: <20230515131353.v2.cover@dianders> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Some Chromebooks with Mediatek SoCs have a problem where the firmware doesn't properly save/restore certain GICR registers. Newer Chromebooks should fix this issue and we may be able to do firmware updates for old Chromebooks. At the moment, the only known issue with these Chromebooks is that we can't enable "pseudo NMIs" since the priority register can be lost. Enabling "pseudo NMIs" on Chromebooks with the problematic firmware causes crashes and freezes. Let's detect devices with this problem and then disable "pseudo NMIs" on them. We'll detect the problem by looking for the presence of the "mediatek,broken-save-restore-fw" property in the GIC device tree node. Any devices with fixed firmware will not have this property. Our detection plan works because we never bake a Chromebook's device tree into firmware. Instead, device trees are always bundled with the kernel. We'll update the device trees of all affected Chromebooks and then we'll never enable "pseudo NMI" on a kernel that is bundled with old device trees. When a firmware update is shipped that fixes this issue it will know to patch the device tree to remove the property. In order to make this work, the quick detection mechanism of the GICv3 code is extended to be able to look for properties in addition to looking at "compatible". Reviewed-by: Julius Werner Signed-off-by: Douglas Anderson Reviewed-by: AngeloGioacchino Del Regno Reviewed-by: Douglas Anderson Tested-by: Geert Uytterhoeven --- Changes in v2: - mediatek,gicr-save-quirk =3D> mediatek,broken-save-restore-fw drivers/irqchip/irq-gic-common.c | 8 ++++++-- drivers/irqchip/irq-gic-common.h | 1 + drivers/irqchip/irq-gic-v3.c | 20 ++++++++++++++++++++ 3 files changed, 27 insertions(+), 2 deletions(-) diff --git a/drivers/irqchip/irq-gic-common.c b/drivers/irqchip/irq-gic-com= mon.c index a610821c8ff2..de47b51cdadb 100644 --- a/drivers/irqchip/irq-gic-common.c +++ b/drivers/irqchip/irq-gic-common.c @@ -16,7 +16,11 @@ void gic_enable_of_quirks(const struct device_node *np, const struct gic_quirk *quirks, void *data) { for (; quirks->desc; quirks++) { - if (!of_device_is_compatible(np, quirks->compatible)) + if (quirks->compatible && + !of_device_is_compatible(np, quirks->compatible)) + continue; + if (quirks->property && + !of_property_read_bool(np, quirks->property)) continue; if (quirks->init(data)) pr_info("GIC: enabling workaround for %s\n", @@ -28,7 +32,7 @@ void gic_enable_quirks(u32 iidr, const struct gic_quirk *= quirks, void *data) { for (; quirks->desc; quirks++) { - if (quirks->compatible) + if (quirks->compatible || quirks->property) continue; if (quirks->iidr !=3D (quirks->mask & iidr)) continue; diff --git a/drivers/irqchip/irq-gic-common.h b/drivers/irqchip/irq-gic-com= mon.h index 27e3d4ed4f32..3db4592cda1c 100644 --- a/drivers/irqchip/irq-gic-common.h +++ b/drivers/irqchip/irq-gic-common.h @@ -13,6 +13,7 @@ struct gic_quirk { const char *desc; const char *compatible; + const char *property; bool (*init)(void *data); u32 iidr; u32 mask; diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index 6fcee221f201..a605aa79435a 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -39,6 +39,7 @@ =20 #define FLAGS_WORKAROUND_GICR_WAKER_MSM8996 (1ULL << 0) #define FLAGS_WORKAROUND_CAVIUM_ERRATUM_38539 (1ULL << 1) +#define FLAGS_WORKAROUND_MTK_GICR_SAVE (1ULL << 2) =20 #define GIC_IRQ_TYPE_PARTITION (GIC_IRQ_TYPE_LPI + 1) =20 @@ -1720,6 +1721,15 @@ static bool gic_enable_quirk_msm8996(void *data) return true; } =20 +static bool gic_enable_quirk_mtk_gicr(void *data) +{ + struct gic_chip_data *d =3D data; + + d->flags |=3D FLAGS_WORKAROUND_MTK_GICR_SAVE; + + return true; +} + static bool gic_enable_quirk_cavium_38539(void *data) { struct gic_chip_data *d =3D data; @@ -1792,6 +1802,11 @@ static const struct gic_quirk gic_quirks[] =3D { .compatible =3D "qcom,msm8996-gic-v3", .init =3D gic_enable_quirk_msm8996, }, + { + .desc =3D "GICv3: Mediatek Chromebook GICR save problem", + .property =3D "mediatek,broken-save-restore-fw", + .init =3D gic_enable_quirk_mtk_gicr, + }, { .desc =3D "GICv3: HIP06 erratum 161010803", .iidr =3D 0x0204043b, @@ -1834,6 +1849,11 @@ static void gic_enable_nmi_support(void) if (!gic_prio_masking_enabled()) return; =20 + if (gic_data.flags & FLAGS_WORKAROUND_MTK_GICR_SAVE) { + pr_warn("Skipping NMI enable due to firmware issues\n"); + return; + } + ppi_nmi_refs =3D kcalloc(gic_data.ppi_nr, sizeof(*ppi_nmi_refs), GFP_KERN= EL); if (!ppi_nmi_refs) return; --=20 2.40.1.606.ga4b1b128d6-goog