From: Douglas Anderson <dianders@chromium.org> To: Marc Zyngier <maz@kernel.org>, Thomas Gleixner <tglx@linutronix.de>, Rob Herring <robh+dt@kernel.org>, Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>, Matthias Brugger <matthias.bgg@gmail.com> Cc: devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Allen-KH Cheng <allen-kh.cheng@mediatek.com>, linux-mediatek@lists.infradead.org, Eddie Huang <eddie.huang@mediatek.com>, Hsin-Hsiung Wang <hsin-hsiung.wang@mediatek.com>, AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>, wenst@chromium.org, yidilin@chromium.org, Tinghan Shen <tinghan.shen@mediatek.com>, jwerner@chromium.org, Weiyi Lu <weiyi.lu@mediatek.com>, Ben Ho <Ben.Ho@mediatek.com>, Seiya Wang <seiya.wang@mediatek.com>, Douglas Anderson <dianders@chromium.org>, Conor Dooley <conor+dt@kernel.org>, linux-kernel@vger.kernel.org Subject: [PATCH v2 1/5] dt-bindings: interrupt-controller: arm,gic-v3: Add quirk for Mediatek SoCs w/ broken FW Date: Mon, 15 May 2023 13:13:50 -0700 [thread overview] Message-ID: <20230515131353.v2.1.Iabe67a827e206496efec6beb5616d5a3b99c1e65@changeid> (raw) In-Reply-To: <20230515131353.v2.cover@dianders> When trying to turn on the "pseudo NMI" kernel feature in Linux, it was discovered that all Mediatek-based Chromebooks that ever shipped (at least ones with GICv3) had a firmware bug where they wouldn't save certain GIC "GICR" registers properly. If a processor ever entered a suspend/idle mode where the GICR registers lost state then they'd be reset to their default state. As a result of the bug, if you try to enable "pseudo NMIs" on the affected devices then certain interrupts will unexpectedly get promoted to be "pseudo NMIs" and cause crashes / freezes / general mayhem. ChromeOS is looking to start turning on "pseudo NMIs" in production to make crash reports more actionable. To do so, we will release firmware updates for at least some of the affected Mediatek Chromebooks. However, even when we update the firmware of a Chromebook it's always possible that a user will end up booting with old firmware. We need to be able to detect when we're running with firmware that will crash and burn if pseudo NMIs are enabled. The current plan is: * Update the device trees of all affected Chromebooks to include the 'mediatek,broken-save-restore-fw' property. The kernel can use this to know not to enable certain features like "pseudo NMI". NOTE: device trees for Chromebooks are never baked into the firmware but are bundled with the kernel. A kernel will never be configured to use "pseudo NMIs" and be bundled with an old device tree. * When we get a fixed firmware for one of these Chromebooks, it will patch the device tree to remove this property. For some details, you can also see the public bug <https://issuetracker.google.com/281831288> Reviewed-by: Julius Werner <jwerner@chromium.org> Signed-off-by: Douglas Anderson <dianders@chromium.org> --- Changes in v2: - "when CPUs are powered" => "when the GIC redistributors are..." - mediatek,gicr-save-quirk => mediatek,broken-save-restore-fw .../bindings/interrupt-controller/arm,gic-v3.yaml | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.yaml b/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.yaml index 92117261e1e1..39e64c7f6360 100644 --- a/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.yaml +++ b/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.yaml @@ -166,6 +166,12 @@ properties: resets: maxItems: 1 + mediatek,broken-save-restore-fw: + type: boolean + description: + Asserts that the firmware on this device has issues saving and restoring + GICR registers when the GIC redistributors are powered off. + dependencies: mbi-ranges: [ msi-controller ] msi-controller: [ mbi-ranges ] -- 2.40.1.606.ga4b1b128d6-goog
WARNING: multiple messages have this Message-ID (diff)
From: Douglas Anderson <dianders@chromium.org> To: Marc Zyngier <maz@kernel.org>, Thomas Gleixner <tglx@linutronix.de>, Rob Herring <robh+dt@kernel.org>, Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>, Matthias Brugger <matthias.bgg@gmail.com> Cc: devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Allen-KH Cheng <allen-kh.cheng@mediatek.com>, linux-mediatek@lists.infradead.org, Eddie Huang <eddie.huang@mediatek.com>, Hsin-Hsiung Wang <hsin-hsiung.wang@mediatek.com>, AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>, wenst@chromium.org, yidilin@chromium.org, Tinghan Shen <tinghan.shen@mediatek.com>, jwerner@chromium.org, Weiyi Lu <weiyi.lu@mediatek.com>, Ben Ho <Ben.Ho@mediatek.com>, Seiya Wang <seiya.wang@mediatek.com>, Douglas Anderson <dianders@chromium.org>, Conor Dooley <conor+dt@kernel.org>, linux-kernel@vger.kernel.org Subject: [PATCH v2 1/5] dt-bindings: interrupt-controller: arm,gic-v3: Add quirk for Mediatek SoCs w/ broken FW Date: Mon, 15 May 2023 13:13:50 -0700 [thread overview] Message-ID: <20230515131353.v2.1.Iabe67a827e206496efec6beb5616d5a3b99c1e65@changeid> (raw) In-Reply-To: <20230515131353.v2.cover@dianders> When trying to turn on the "pseudo NMI" kernel feature in Linux, it was discovered that all Mediatek-based Chromebooks that ever shipped (at least ones with GICv3) had a firmware bug where they wouldn't save certain GIC "GICR" registers properly. If a processor ever entered a suspend/idle mode where the GICR registers lost state then they'd be reset to their default state. As a result of the bug, if you try to enable "pseudo NMIs" on the affected devices then certain interrupts will unexpectedly get promoted to be "pseudo NMIs" and cause crashes / freezes / general mayhem. ChromeOS is looking to start turning on "pseudo NMIs" in production to make crash reports more actionable. To do so, we will release firmware updates for at least some of the affected Mediatek Chromebooks. However, even when we update the firmware of a Chromebook it's always possible that a user will end up booting with old firmware. We need to be able to detect when we're running with firmware that will crash and burn if pseudo NMIs are enabled. The current plan is: * Update the device trees of all affected Chromebooks to include the 'mediatek,broken-save-restore-fw' property. The kernel can use this to know not to enable certain features like "pseudo NMI". NOTE: device trees for Chromebooks are never baked into the firmware but are bundled with the kernel. A kernel will never be configured to use "pseudo NMIs" and be bundled with an old device tree. * When we get a fixed firmware for one of these Chromebooks, it will patch the device tree to remove this property. For some details, you can also see the public bug <https://issuetracker.google.com/281831288> Reviewed-by: Julius Werner <jwerner@chromium.org> Signed-off-by: Douglas Anderson <dianders@chromium.org> --- Changes in v2: - "when CPUs are powered" => "when the GIC redistributors are..." - mediatek,gicr-save-quirk => mediatek,broken-save-restore-fw .../bindings/interrupt-controller/arm,gic-v3.yaml | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.yaml b/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.yaml index 92117261e1e1..39e64c7f6360 100644 --- a/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.yaml +++ b/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.yaml @@ -166,6 +166,12 @@ properties: resets: maxItems: 1 + mediatek,broken-save-restore-fw: + type: boolean + description: + Asserts that the firmware on this device has issues saving and restoring + GICR registers when the GIC redistributors are powered off. + dependencies: mbi-ranges: [ msi-controller ] msi-controller: [ mbi-ranges ] -- 2.40.1.606.ga4b1b128d6-goog _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2023-05-15 20:16 UTC|newest] Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top 2023-05-15 20:13 [PATCH v2 0/5] irqchip/gic-v3: Disable pseudo NMIs on Mediatek Chromebooks w/ bad FW Douglas Anderson 2023-05-15 20:13 ` Douglas Anderson 2023-05-15 20:13 ` Douglas Anderson [this message] 2023-05-15 20:13 ` [PATCH v2 1/5] dt-bindings: interrupt-controller: arm,gic-v3: Add quirk for Mediatek SoCs w/ broken FW Douglas Anderson 2023-05-16 10:22 ` [irqchip: irq/irqchip-fixes] " irqchip-bot for Douglas Anderson 2023-05-16 13:24 ` [PATCH v2 1/5] " AngeloGioacchino Del Regno 2023-05-16 13:24 ` AngeloGioacchino Del Regno 2023-05-15 20:13 ` [PATCH v2 2/5] irqchip/gic-v3: Disable pseudo NMIs on Mediatek devices w/ firmware issues Douglas Anderson 2023-05-15 20:13 ` Douglas Anderson 2023-05-16 10:22 ` [irqchip: irq/irqchip-fixes] " irqchip-bot for Douglas Anderson 2023-05-16 13:23 ` [PATCH v2 2/5] " AngeloGioacchino Del Regno 2023-05-16 13:23 ` AngeloGioacchino Del Regno 2023-05-16 14:19 ` Doug Anderson 2023-05-16 14:19 ` Doug Anderson 2023-05-16 14:57 ` Marc Zyngier 2023-05-16 14:57 ` Marc Zyngier 2023-05-30 8:29 ` Geert Uytterhoeven 2023-05-30 8:29 ` Geert Uytterhoeven 2023-05-30 9:46 ` Marc Zyngier 2023-05-30 9:46 ` Marc Zyngier 2023-05-30 9:58 ` Geert Uytterhoeven 2023-05-30 9:58 ` Geert Uytterhoeven 2023-05-30 16:36 ` Doug Anderson 2023-05-30 16:36 ` Doug Anderson 2023-05-15 20:13 ` [PATCH v2 3/5] arm64: dts: mediatek: mt8183: Add mediatek,broken-save-restore-fw to kukui Douglas Anderson 2023-05-15 20:13 ` Douglas Anderson 2023-05-16 13:18 ` AngeloGioacchino Del Regno 2023-05-16 13:18 ` AngeloGioacchino Del Regno 2023-05-15 20:13 ` [PATCH v2 4/5] arm64: dts: mediatek: mt8192: Add mediatek,broken-save-restore-fw to asurada Douglas Anderson 2023-05-15 20:13 ` Douglas Anderson 2023-05-16 13:18 ` AngeloGioacchino Del Regno 2023-05-16 13:18 ` AngeloGioacchino Del Regno 2023-05-15 20:13 ` [PATCH v2 5/5] arm64: dts: mediatek: mt8195: Add mediatek,broken-save-restore-fw to cherry Douglas Anderson 2023-05-15 20:13 ` Douglas Anderson 2023-05-16 13:18 ` AngeloGioacchino Del Regno 2023-05-16 13:18 ` AngeloGioacchino Del Regno 2023-05-16 9:58 ` [PATCH v2 0/5] irqchip/gic-v3: Disable pseudo NMIs on Mediatek Chromebooks w/ bad FW Marc Zyngier 2023-05-16 9:58 ` Marc Zyngier 2023-05-29 15:41 ` Matthias Brugger 2023-05-29 15:41 ` Matthias Brugger
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