From nobody Thu Sep 18 17:16:59 2025 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 772E8C4321E for ; Mon, 5 Dec 2022 10:09:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230193AbiLEKJW (ORCPT ); Mon, 5 Dec 2022 05:09:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49662 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229985AbiLEKJT (ORCPT ); Mon, 5 Dec 2022 05:09:19 -0500 Received: from mail.marcansoft.com (marcansoft.com [212.63.210.85]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E90F2183AA for ; Mon, 5 Dec 2022 02:09:17 -0800 (PST) Received: from [127.0.0.1] (localhost [127.0.0.1]) (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: sendonly@marcansoft.com) by mail.marcansoft.com (Postfix) with ESMTPSA id DF71242137; Mon, 5 Dec 2022 10:09:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=marcan.st; s=default; t=1670234956; bh=/lyXjIyUIb+1pgEaMmUwZNYl0uV1GrDjGWI2beTmvj0=; h=From:To:Cc:Subject:Date; b=m5sgsXXtSrqefqkY+9rLDHCdHtIuKLYn/OuPT+lybjBXgnPgK4kP9ZReDUcpmDmoS c1/7bQzBphZxXoYjhy/8FMOxpVooUeVACX4o7mCPZ+jfRJoYUMoptCKE8bSspRqQn1 G9qJxD3f1sHwP9JbMmaV7DvbMf5WgxYWa+MN/2dyc7ECMe+53CxF/L/2RgEH2evwAh T5erlbKK2tLu4HcbSoBGNiFfR7wnLb2/RGpWWc/zbZOx/+gzTXbCkQg+HSehHcZAEV AeoMO8Mz2cYYR6HWiPgNT6HcU0IK0G7PvYZ/XaA8t2Az8Gi6KSVAGqqZjwgAZRYE23 QlU6oP/9NfpVg== From: Hector Martin To: Joerg Roedel , Will Deacon , Robin Murphy Cc: Sven Peter , Alyssa Rosenzweig , asahi@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Hector Martin Subject: [PATCH] iommu: dart: Add suspend/resume support Date: Mon, 5 Dec 2022 19:09:07 +0900 Message-Id: <20221205100907.10230-1-marcan@marcan.st> X-Mailer: git-send-email 2.35.1 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" We need to save/restore the TCR/TTBR registers, since they are lost on power gate. Signed-off-by: Hector Martin Reviewed-by: Sven Peter --- drivers/iommu/apple-dart.c | 50 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c index 4f4a323be0d0..ed524765ad87 100644 --- a/drivers/iommu/apple-dart.c +++ b/drivers/iommu/apple-dart.c @@ -121,6 +121,9 @@ struct apple_dart { =20 struct iommu_group *sid2group[DART_MAX_STREAMS]; struct iommu_device iommu; + + u32 save_tcr[DART_MAX_STREAMS]; + u32 save_ttbr[DART_MAX_STREAMS][DART_MAX_TTBR]; }; =20 /* @@ -932,6 +935,50 @@ static const struct apple_dart_hw apple_dart_hw_t6000 = =3D { .fmt =3D APPLE_DART2, }; =20 +#ifdef CONFIG_PM_SLEEP +static int apple_dart_suspend(struct device *dev) +{ + struct apple_dart *dart =3D dev_get_drvdata(dev); + unsigned int sid, idx; + + for (sid =3D 0; sid < DART_MAX_STREAMS; sid++) { + dart->save_tcr[sid] =3D readl_relaxed(dart->regs + DART_TCR(sid)); + for (idx =3D 0; idx < DART_MAX_TTBR; idx++) + dart->save_ttbr[sid][idx] =3D + readl_relaxed(dart->regs + DART_TTBR(sid, idx)); + } + + return 0; +} + +static int apple_dart_resume(struct device *dev) +{ + struct apple_dart *dart =3D dev_get_drvdata(dev); + unsigned int sid, idx; + int ret; + + ret =3D apple_dart_hw_reset(dart); + if (ret) { + dev_err(dev, "Failed to reset DART on resume\n"); + return ret; + } + + for (sid =3D 0; sid < DART_MAX_STREAMS; sid++) { + for (idx =3D 0; idx < DART_MAX_TTBR; idx++) + writel_relaxed(dart->save_ttbr[sid][idx], + dart->regs + DART_TTBR(sid, idx)); + writel_relaxed(dart->save_tcr[sid], dart->regs + DART_TCR(sid)); + } + + return 0; +} + +static const struct dev_pm_ops apple_dart_pm_ops =3D { + .suspend =3D apple_dart_suspend, + .resume =3D apple_dart_resume, +}; +#endif + static const struct of_device_id apple_dart_of_match[] =3D { { .compatible =3D "apple,t8103-dart", .data =3D &apple_dart_hw_t8103 }, { .compatible =3D "apple,t6000-dart", .data =3D &apple_dart_hw_t6000 }, @@ -944,6 +991,9 @@ static struct platform_driver apple_dart_driver =3D { .name =3D "apple-dart", .of_match_table =3D apple_dart_of_match, .suppress_bind_attrs =3D true, +#ifdef CONFIG_PM_SLEEP + .pm =3D &apple_dart_pm_ops, +#endif }, .probe =3D apple_dart_probe, .remove =3D apple_dart_remove, --=20 2.35.1