Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753774Ab3JUIve (ORCPT ); Mon, 21 Oct 2013 04:51:34 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:39523 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753694Ab3JUIv1 (ORCPT ); Mon, 21 Oct 2013 04:51:27 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Alex Deucher" Date: Mon, 21 Oct 2013 09:46:28 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 062/149] drm/radeon/atom: workaround vbios bug in transmitter table on rs880 (v2) In-Reply-To: X-SA-Exim-Connect-IP: 212.20.242.100 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2452 Lines: 55 3.2.52-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Alex Deucher commit 91f3a6aaf280294b07c05dfe606e6c27b7ba3c72 upstream. The OUTPUT_ENABLE action jumps past the point in the coder where the data_offset is set on certain rs780 cards. This worked previously because the OUTPUT_ENABLE action is always called immediately after the ENABLE action so the data_offset remained set. In 6f8bbaf568c7f2c497558bfd04654c0b9841ad57 (drm/radeon/atom: initialize more atom interpretor elements to 0), we explictly reset data_offset to 0 between atom calls which then caused this to fail. The fix is to just skip calling the OUTPUT_ENABLE action on the problematic chipsets. The ENABLE action does the same thing and more. Ultimately, we could probably drop the OUTPUT_ENABLE action all together on DCE3 asics. fixes: https://bugzilla.kernel.org/show_bug.cgi?id=60791 v2: only rs880 seems to be affected Signed-off-by: Alex Deucher Signed-off-by: Ben Hutchings --- drivers/gpu/drm/radeon/atombios_encoders.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/radeon/atombios_encoders.c +++ b/drivers/gpu/drm/radeon/atombios_encoders.c @@ -1385,8 +1385,12 @@ radeon_atom_encoder_dpms_dig(struct drm_ atombios_dig_encoder_setup(encoder, ATOM_ENABLE, 0); atombios_dig_transmitter_setup(encoder, ATOM_TRANSMITTER_ACTION_SETUP, 0, 0); atombios_dig_transmitter_setup(encoder, ATOM_TRANSMITTER_ACTION_ENABLE, 0, 0); - /* some early dce3.2 boards have a bug in their transmitter control table */ - if ((rdev->family != CHIP_RV710) && (rdev->family != CHIP_RV730)) + /* some dce3.x boards have a bug in their transmitter control table. + * ACTION_ENABLE_OUTPUT can probably be dropped since ACTION_ENABLE + * does the same thing and more. + */ + if ((rdev->family != CHIP_RV710) && (rdev->family != CHIP_RV730) && + (rdev->family != CHIP_RS880)) atombios_dig_transmitter_setup(encoder, ATOM_TRANSMITTER_ACTION_ENABLE_OUTPUT, 0, 0); } if (ENCODER_MODE_IS_DP(atombios_get_encoder_mode(encoder)) && connector) { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/