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 D2AA75C613; Thu, 30 Jul 2026 14:37:21 +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=1785422242; cv=none; b=l0tx2LqAKGVeAZMnLznXWyVuNYJo/VGjaAz7Svsamyf2uej6nEkWphIqlwE4CpiaWMBSXJ89sLVs65hh40RpYtrcDIkXO/+8Eo1tqy0bPFZXdsGcKf2KuQ5EgeGYv1WxYGiLOF770gaep1tM11Jhcge2MkqgF2NOf62XS2WNITc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785422242; c=relaxed/simple; bh=TPTGiMWuZ7oD/uwwfCi5eI0gejZi6dc7Llv1x6L6ZDg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Dii63Tt1Bb/LNIZItSpg5ZNdtsKGtixaMArfnb0hpR5BUTMJKTItuaNuBvyn9nh0YyhP2I5ZE+nuMy3YZDSip/hobYqiHoXTDQaIct/Cvy4clyk2PRVGucVQbubQz1G5xqwp4VbGAoL5wnxU6y0AYBTVKblZkYNpajR3HKb/0w0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=oOnWNgMu; 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="oOnWNgMu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E0B691F000E9; Thu, 30 Jul 2026 14:37:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785422241; bh=ZRWAfVnAXM+T4XHu0BOwkrSfaUQJONeMuOw/eHpN5ZE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=oOnWNgMuTjO6UABa41cxjtRWNGyBZN6t2JWYxOI1MqBSScgYA37wYD2Oft43AlND1 XKbheT839P5jVFYuym5LU+SsBHiFTUmukamKkvwscBeFsaHtWPUJsmAnvTSogDbWDj OFb86EzCnqCuW5zMhPU7NP0w/Sjhe9EULzZ9twyM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Shubhankar Milind Sardeshpande , Suresh Guttula , Alex Deucher Subject: [PATCH 7.1 373/744] drm/amd/pm: re-enable MC access after PrepareMp1ForUnload on SMU V15 APUs Date: Thu, 30 Jul 2026 16:10:46 +0200 Message-ID: <20260730141452.215277663@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141444.267951807@linuxfoundation.org> References: <20260730141444.267951807@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: Shubhankar Milind Sardeshpande commit 76589bcc73f477ef2b3b90e4fae6a7a4dfd925af upstream. During smu_v15_0_0_system_features_control(), the driver sends a PrepareMp1ForUnload message to PMFW. PMFW then performs nBIF and SYSHUB function-level resets (FLR), disabling PCIe CFG space reset, which clears the framebuffer enable bit to zero and disables MC (memory controller) access from the host. Re-enable MC access via the nbio mc_access_enable callback right after PrepareMp1ForUnload completes in smu_v15_0_0_system_features_control(). Signed-off-by: Shubhankar Milind Sardeshpande Signed-off-by: Suresh Guttula Signed-off-by: Alex Deucher (cherry picked from commit 840a3c5aeae779a3bc75d7f747c3ed18b1af6507) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/amd/pm/swsmu/smu15/smu_v15_0_0_ppt.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/amd/pm/swsmu/smu15/smu_v15_0_0_ppt.c +++ b/drivers/gpu/drm/amd/pm/swsmu/smu15/smu_v15_0_0_ppt.c @@ -227,9 +227,14 @@ static int smu_v15_0_0_system_features_c struct amdgpu_device *adev = smu->adev; int ret = 0; - if (!en && !adev->in_s0ix) + if (!en && !adev->in_s0ix) { ret = smu_cmn_send_smc_msg(smu, SMU_MSG_PrepareMp1ForUnload, NULL); + /* SMU resets BIF_FB_EN to zero, re-enable MC access on APUs with SMU V15 */ + if (!ret && adev->nbio.funcs && adev->nbio.funcs->mc_access_enable) + adev->nbio.funcs->mc_access_enable(adev, true); + } + return ret; }