From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794063534; b=ToZ+6vsbPLMjq/699/+6QvtoFyS7vUgwlHC4jHQ4uuOXAqJz4xkeIYJi5gn3A0dglp/y DIakwxrP1bjHgPzK1nH8iIPVaDixR1vicJsA/zCfz7Be40Ve/Ok6FsqhgKMrvgi8H5i97 aDoOfe4v9j14IbmSECv8mu6uaxd9wmBHG1C/cNI4dH8A8W2a4ywLQpkSI9y8t3fq76WeX 2qCj3N4Z8xfPAXTuAoFqIM0RWI9AtuEYZWKwXkjxna/qoEKAuEctbRw7mv8y6ui6TUGVc hhM7VQkjsVyyd5HLrK5e/Kx9bUGeyl4z9ISeQnScdRr1UGbwh9zI8semI552ETKYEZA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794063534; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=GTW6N/Sv93+fmPc+b8MeK+UFfwXZ4qaWrB+rmhK1wco=; b=jvzxBo1RvKj5dJ8HMJ+ut57O9o4F1fg/v/rmctXZLesUxZBptvoUofO2J/UW4bqsbkky 23Am8+hcDg2aIQWafCth3Y6ipukRpzjzQmNxzevSLJmt3uquszRnJc3O7d98slL9KMb05 H19DsxU4bZz6CxJH/ZklL+JAVM3xMgWMlUl92Js8tkMRLooSBSpb0AXIwRnoM5E4V+X1n Zz8shO8beWDv7w4TT1Y2/BbRvkXDnRtHbCI7Bg9lwxvKiGTIg2Z0fSMft3gt8kn6Tdsl2 xEGa/Z/jGV2qs5gnjBEO8Z6srCph3Xbi1FtmyPWaLVbYjiehs//NrVlR1TzcPV662Vw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=vjPX5fbd; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7C50B606EEB8; Sat, 7 Nov 2026 14:58:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=vjPX5fbd Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2B0F51F008A1; Sat, 7 Nov 2026 14:58:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794063534; bh=GTW6N/Sv93+fmPc+b8MeK+UFfwXZ4qaWrB+rmhK1wco=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=vjPX5fbdCZ5BiTlBO7oiA2ulm2xI1LwlTNbRfpxHPoR0aC1EHxujp8kM8WchD41Av fvx5uqk+fs45nGHG/7SZ91yvtohK/aK97K6tnTFvrHKVAISpVKEUqodODUys9OZcCi db3UEMS7lfar3ONUJGCBC5aosm24Q8c7MID5CQFg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alex Deucher , Maciej Kucharek , Sasha Levin Subject: [PATCH 6.18 671/869] drm/amdgpu: reset SI ASIC on MacBookPros with VRAM at 0 Date: Sat, 7 Nov 2026 08:55:53 -0500 Message-ID: <20261107134915.861774557@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134852.069646174@linuxfoundation.org> References: <20261107134852.069646174@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Maciej Kucharek [ Upstream commit 5b56ede880317bd912f914d5cd38ba1d357677fa ] On MacBookPros with switchable graphics, the firmware puts VRAM at MC address 0 when the iGPU is enabled. The EFI stub enables the iGPU on these machines through apple_set_os(). On a MacBookPro11,5 (Radeon R9 M370X, 1002:6821, subsystem 106b:0149), the driver adopts this layout at init: MC_VM_FB_LOCATION=0x007f0000, HDP_NONSURFACE_BASE=0 VRAM at 0x0-0x7fffffff, GART table at 0x1400000 The driver posts the ASIC again on S3 resume and after a GPU reset. The VBIOS asic_init table then moves VRAM back to the VBIOS default: MC_VM_FB_LOCATION=0xf47ff400, HDP_NONSURFACE_BASE=0xf4000000 gmc_v6_0 does not reprogram these registers. The GART table is then no longer in VRAM, and the gfx ring test times out: amdgpu: ring gfx test failed (-110) amdgpu: resume of IP block failed -110 Reset and post the ASIC at driver load on Apple boards with VRAM at 0. The driver then uses the VBIOS layout (VRAM at 0xf400000000) from the start, and later posts keep it. After the reset, FB_BASE is not 0, so a module reload does not reset the ASIC again. The test is the same one that commit c54e4d105077 ("drm/amdgpu: make Mac FB workaround generic") uses: an Apple subsystem vendor and VRAM at 0. The VI quirk for the MacBookPro14,3 resets at load for the same reason: commit b6b1d9721851 ("drm/amdgpu: reset VI ASIC on MacBookPro14,3") Other Apple SI boards get the same reset if FB_BASE reads 0 at load. Tested on a MacBookPro11,5 with 7.2.5 and this patch: the panel comes up at boot, and 4 of 4 deep S3 cycles resume. Without the patch, S3 resume fails every time. The GPU reset path is not tested. Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/5978 Assisted-by: Claude:claude-opus-5-5 Reviewed-by: Alex Deucher Signed-off-by: Maciej Kucharek Signed-off-by: Alex Deucher (cherry picked from commit 60dd16ae10f286cb9cce5b6027b2d5ee869637af) Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin --- drivers/gpu/drm/amd/amdgpu/si.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/si.c b/drivers/gpu/drm/amd/amdgpu/si.c index e0f139de79915..0c96a40fe4b4a 100644 --- a/drivers/gpu/drm/amd/amdgpu/si.c +++ b/drivers/gpu/drm/amd/amdgpu/si.c @@ -1524,6 +1524,16 @@ static bool si_need_full_reset(struct amdgpu_device *adev) static bool si_need_reset_on_init(struct amdgpu_device *adev) { + /* + * MacBookPros with switchable graphics put VRAM at 0 when the iGPU + * is enabled. Any later post (S3 resume, GPU reset) moves it back to + * the vbios default, so reset and post on load to start with the + * vbios layout. + */ + if (adev->pdev->subsystem_vendor == PCI_VENDOR_ID_APPLE && + !(RREG32(mmMC_VM_FB_LOCATION) & MC_VM_FB_LOCATION__FB_BASE_MASK)) + return true; + return false; } -- 2.53.0