From patchwork Thu Jul 19 20:35:49 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matt Atwood X-Patchwork-Id: 10535291 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id C1039600D0 for ; Thu, 19 Jul 2018 20:35:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B42E729B03 for ; Thu, 19 Jul 2018 20:35:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A85EC29B1C; Thu, 19 Jul 2018 20:35:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 4EC0729B03 for ; Thu, 19 Jul 2018 20:35:53 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B531C6EEBD; Thu, 19 Jul 2018 20:35:51 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by gabe.freedesktop.org (Postfix) with ESMTPS id CB6A66EEBD; Thu, 19 Jul 2018 20:35:50 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 19 Jul 2018 13:35:50 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,375,1526367600"; d="scan'208";a="57889985" Received: from smaug.jf.intel.com ([10.24.10.15]) by orsmga007.jf.intel.com with ESMTP; 19 Jul 2018 13:35:50 -0700 From: matthew.s.atwood@intel.com To: manasi.d.navare@intel.com, rodrigo.vivi@intel.com, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Date: Thu, 19 Jul 2018 13:35:49 -0700 Message-Id: <20180719203549.28266-2-matthew.s.atwood@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180719203549.28266-1-matthew.s.atwood@intel.com> References: <20180717214939.32260-2-matthew.s.atwood@intel.com> <20180719203549.28266-1-matthew.s.atwood@intel.com> Subject: [Intel-gfx] [PATCH 2/2] drm/i915: implement EXTENDED_RECEIVER_CAPABILITY_FIELD_PRESENT X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP From: Matt Atwood According to DP spec (2.9.3.1 of DP 1.4) if EXTENDED_RECEIVER_CAPABILITY_FIELD_PRESENT is set the addresses in DPCD 02200h through 0220Fh shall contain the DPRX's true capability. These values will match 00000h through 0000Fh, except for DPCD_REV, MAX_LINK_RATE, DOWN_STREAM_PORT_PRESENT. Read from DPCD once for all 3 values as this is an expensive operation. Spec mentions that all of address space 02200h through 0220Fh should contain the right information however currently only 3 values can differ. There is no address space in the intel_dp->dpcd struct for addresses 02200h through 0220Fh, and since so much of the data is a identical, simply overwrite the values stored in 00000h through 0000Fh with the values that can be overwritten from addresses 02200h through 0220Fh. This patch helps with backward compatibility for devices pre DP1.3. v2: read only dpcd values which can be affected, remove incorrect check, split into drm include changes into separate patch, commit message, verbose debugging statements during overwrite. v3: white space fixes Signed-off-by: Matt Atwood --- drivers/gpu/drm/i915/intel_dp.c | 37 +++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index dde92e4af5d3..a31fbbbd7954 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -3738,6 +3738,43 @@ intel_dp_read_dpcd(struct intel_dp *intel_dp) sizeof(intel_dp->dpcd)) < 0) return false; /* aux transfer failed */ + if (intel_dp->dpcd[DP_TRAINING_AUX_RD_INTERVAL] & + DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT) { + uint8_t dpcd_ext[6]; + + DRM_DEBUG_KMS("DPCD: Extended Receiver Capability Field Present, accessing 02200h through 022FFh\n"); + + if (drm_dp_dpcd_read(&intel_dp->aux, DP_DP13_DPCD_REV, + &dpcd_ext, sizeof(dpcd_ext)) < 0) + return false; /* aux transfer failed */ + + if (memcmp(&intel_dp->dpcd[DP_DPCD_REV], &dpcd_ext[DP_DPCD_REV], + sizeof(u8))) { + DRM_DEBUG_KMS("DPCD: new value for DPCD Revision previous value %2x new value %2x\n", + intel_dp->dpcd[DP_DPCD_REV], + dpcd_ext[DP_DPCD_REV]); + memcpy(&intel_dp->dpcd[DP_DPCD_REV], + &dpcd_ext[DP_DPCD_REV], + sizeof(u8)); + } + if (memcmp(&intel_dp->dpcd[DP_MAX_LINK_RATE], + &dpcd_ext[DP_MAX_LINK_RATE], sizeof(u8))) { + DRM_DEBUG_KMS("DPCD: new value for DPCD Max Link Rate previous value %2x new value %2x\n", + intel_dp->dpcd[DP_MAX_LINK_RATE], + dpcd_ext[DP_MAX_LINK_RATE]); + memcpy(&intel_dp->dpcd[DP_MAX_LINK_RATE], + &dpcd_ext[DP_MAX_LINK_RATE], sizeof(u8)); + } + if (memcmp(&intel_dp->dpcd[DP_DOWNSTREAMPORT_PRESENT], + &dpcd_ext[DP_DOWNSTREAMPORT_PRESENT], sizeof(u8))) { + DRM_DEBUG_KMS("DPCD: new value for DPCD Downstream Port Present previous value %2x new value %2x\n", + intel_dp->dpcd[DP_DOWNSTREAMPORT_PRESENT], + dpcd_ext[DP_DOWNSTREAMPORT_PRESENT]); + memcpy(&intel_dp->dpcd[DP_DOWNSTREAMPORT_PRESENT], + &dpcd_ext[DP_DOWNSTREAMPORT_PRESENT], + sizeof(u8)); + } + } DRM_DEBUG_KMS("DPCD: %*ph\n", (int) sizeof(intel_dp->dpcd), intel_dp->dpcd); return intel_dp->dpcd[DP_DPCD_REV] != 0;