From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 516F737C925; Thu, 20 Aug 2026 15:05:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787238349; cv=none; b=tBL+XUdCPF2JfNI5s2ZptirufqkowUqkAwZhBVT0XvUm1ZsEnciH3OwFT+9Yt5tqmmvV+ya26DxCNiQfSS/MFzBlf85tTujF5ivIfC2LSrJG5BFuPi80qdzKgMdKkazeFgl2G0iKai9QypS5uSzHCsBBefN4d6/3dg1MBhhFsjg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787238349; c=relaxed/simple; bh=vIJInOsw3BxLbpa6GUe76Aew8/64sdwNY1quB4tHrQ4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=oW+AZS1sdL3EapFxEZpkg4bIVJLykffOpoqU9aHTMXt7FrGEa9+8ou3ATaTjE335wnhSyxs7G4G5Yc3jMrJHlZf2xObB1pjkfMSmk5IS6+1TcIpOk9AbElErgUNa4PzfMz3xf8J55TZ40ygo2wVkKNao61LP0pgCn1Ncl5/a1ms= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=e9ePCUzF; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="e9ePCUzF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 569FC1F000E9; Thu, 20 Aug 2026 15:05:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787238347; bh=MJZ8rgicMWDyafNIAiN9cdcLZhMaD3xlWkuSKem12r4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=e9ePCUzF2XXVTJteTr22Fkh559BOD/qo5PN3deHcM2dAZyQWH2u0J993f8SdfvU2h PO1Axiti0QdTop5NuvYQx+y/t0SsnwIwMyqhiDVQAqjDJnv0woKnaJ+wrhRNGvD+oJ blZBzHwGbn/VaeCmtUkFyXBti486NhxacezW0QOM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yang Wang , Hawking Zhang , Kenneth Feng , Alex Deucher Subject: [PATCH 7.1 117/228] drm/amdgpu: check ASPM on the dGPU host link Date: Thu, 20 Aug 2026 16:54:19 +0200 Message-ID: <20260820145248.188845303@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260820145244.450574346@linuxfoundation.org> References: <20260820145244.450574346@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yang Wang commit 2a9c5154a5650c09ad44ff5e1dff74754e15a3c6 upstream. dGPUs with an internal PCIe switch expose graphics functions below the switch downstream port. The automatic ASPM check uses the display endpoint and evaluates the internal link instead of the host link. Use the switch upstream port for the check and report the selected link. Fixes: 0ab5d711ec74 ("drm/amd: Refactor `amdgpu_aspm` to be evaluated per device") Signed-off-by: Yang Wang Reviewed-by: Hawking Zhang Reviewed-by: Kenneth Feng Signed-off-by: Alex Deucher (cherry picked from commit 4e0d6f2876e704fff707b18c40dbd383aea4a1c9) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 50 ++++++++++++++++++++++++++++- 1 file changed, 49 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c @@ -1365,6 +1365,31 @@ static bool amdgpu_device_aspm_support_q #endif } +/* + * Some dGPUs expose their display endpoint below an internal PCIe switch. + * Use the switch upstream port to query the host-facing link. + */ +static struct pci_dev *amdgpu_device_get_aspm_pdev(struct amdgpu_device *adev) +{ + struct pci_dev *swds, *swus; + + swds = pci_upstream_bridge(adev->pdev); + if (!swds || + (swds->vendor != PCI_VENDOR_ID_ATI && + swds->vendor != PCI_VENDOR_ID_AMD) || + pci_pcie_type(swds) != PCI_EXP_TYPE_DOWNSTREAM) + return adev->pdev; + + swus = pci_upstream_bridge(swds); + if (!swus || + (swus->vendor != PCI_VENDOR_ID_ATI && + swus->vendor != PCI_VENDOR_ID_AMD) || + pci_pcie_type(swus) != PCI_EXP_TYPE_UPSTREAM) + return adev->pdev; + + return swus; +} + /** * amdgpu_device_should_use_aspm - check if the device should program ASPM * @@ -1377,6 +1402,9 @@ static bool amdgpu_device_aspm_support_q */ bool amdgpu_device_should_use_aspm(struct amdgpu_device *adev) { + struct pci_dev *aspm_pdev, *parent; + bool enabled; + switch (amdgpu_aspm) { case -1: break; @@ -1391,7 +1419,27 @@ bool amdgpu_device_should_use_aspm(struc return false; if (amdgpu_device_aspm_support_quirk(adev)) return false; - return pcie_aspm_enabled(adev->pdev); + + /* + * pcie_aspm_enabled() checks the link between its argument and + * the immediate upstream bridge. Use SWUS for dGPUs with an + * internal switch so that this is the host-facing link. + */ + aspm_pdev = amdgpu_device_get_aspm_pdev(adev); + parent = pci_upstream_bridge(aspm_pdev); + if (!parent) { + dev_dbg(adev->dev, "ASPM: no upstream PCIe link for %s\n", + pci_name(aspm_pdev)); + return false; + } + + enabled = pcie_aspm_enabled(aspm_pdev); + /* Report the exact link used for the automatic ASPM decision. */ + dev_dbg(adev->dev, "ASPM: link %s <-> %s is %s\n", + pci_name(parent), pci_name(aspm_pdev), + enabled ? "enabled" : "disabled"); + + return enabled; } /* if we get transitioned to only one device, take VGA back */