From nobody Fri Sep 20 13:46:14 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 194DCC001DC for ; Thu, 20 Jul 2023 20:08:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229819AbjGTUIH (ORCPT ); Thu, 20 Jul 2023 16:08:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56034 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230173AbjGTUIF (ORCPT ); Thu, 20 Jul 2023 16:08:05 -0400 Received: from madras.collabora.co.uk (madras.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e5ab]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7AA90ED; Thu, 20 Jul 2023 13:08:04 -0700 (PDT) Received: from notapiano.myfiosgateway.com (zone.collabora.co.uk [167.235.23.81]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: nfraprado) by madras.collabora.co.uk (Postfix) with ESMTPSA id 134E86607090; Thu, 20 Jul 2023 21:08:00 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1689883683; bh=q4fuY2sBxPima8ZJjGLmr5uxehT6OzQWdozbhPSZu+U=; h=From:To:Cc:Subject:Date:From; b=gGgk+y0lWDU7OZlur4njWxpvtgz8F37oiLPkhWxHa94nXWnBkfsmBcUQ7igmMplxt oIYzYgPseJV4YazM7MPyfWHuk1gxRJTcJ8VvrZKN4K/rUcoj94z6Kr2+X7l/hgDSWY kr1+GxlBcLIfWel5c4HAI0iiD1xGBCZcEY27Jyy1FQG5m3Wx2fxaewu5v8rvV1T+n+ dEpKpdI/FFJtAfHCj46UzJ2Q30esCp79qalPhv6eWZoRneXzKxPzBBhnoToW+a5WJg ZcsKJvqtCTx+b0P1bHl+YSoQpwUS6OFGmamZVc85AECSE0wIwBcCdJSnwRR/trvouG oLt54JiNIBomg== From: =?UTF-8?q?N=C3=ADcolas=20F=2E=20R=2E=20A=2E=20Prado?= To: Matthias Brugger Cc: AngeloGioacchino Del Regno , kernel@collabora.com, Chen-Yu Tsai , =?UTF-8?q?N=C3=ADcolas=20F=2E=20R=2E=20A=2E=20Prado?= , Conor Dooley , Krzysztof Kozlowski , Rob Herring , Seiya Wang , Tinghan Shen , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org Subject: [PATCH] arm64: dts: mediatek: mt8195: Set DSU PMU status to fail Date: Thu, 20 Jul 2023 16:07:51 -0400 Message-ID: <20230720200753.322133-1-nfraprado@collabora.com> X-Mailer: git-send-email 2.41.0 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The DSU PMU allows monitoring performance events in the DSU cluster, which is done by configuring and reading back values from the DSU PMU system registers. However, for write-access to be allowed by ELs lower than EL3, the EL3 firmware needs to update the setting on the ACTLR3_EL3 register, as it is disallowed by default. That configuration is not done on the firmware used by the MT8195 SoC, as a consequence, booting a MT8195-based machine like mt8195-cherry-tomato-r2 with CONFIG_ARM_DSU_PMU enabled hangs the kernel just as it writes to the CLUSTERPMOVSCLR_EL1 register, since the instruction faults to EL3, and BL31 apparently just re-runs the instruction over and over. Mark the DSU PMU node in the Devicetree with status "fail", as the machine doesn't have a suitable firmware to make use of it from the kernel, and allowing its driver to probe would hang the kernel. Fixes: 37f2582883be ("arm64: dts: Add mediatek SoC mt8195 and evaluation bo= ard") Signed-off-by: N=C3=ADcolas F. R. A. Prado Reviewed-by: AngeloGioacchino Del Regno --- arch/arm64/boot/dts/mediatek/mt8195.dtsi | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/boot/dts/mediatek/mt8195.dtsi b/arch/arm64/boot/dts= /mediatek/mt8195.dtsi index 5c670fce1e47..0705d9c3a6a7 100644 --- a/arch/arm64/boot/dts/mediatek/mt8195.dtsi +++ b/arch/arm64/boot/dts/mediatek/mt8195.dtsi @@ -313,6 +313,7 @@ dsu-pmu { interrupts =3D ; cpus =3D <&cpu0>, <&cpu1>, <&cpu2>, <&cpu3>, <&cpu4>, <&cpu5>, <&cpu6>, <&cpu7>; + status =3D "fail"; }; =20 dmic_codec: dmic-codec { --=20 2.41.0