From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0E3B5EB64DA for ; Fri, 16 Jun 2023 17:40:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230259AbjFPRkl (ORCPT ); Fri, 16 Jun 2023 13:40:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34318 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229470AbjFPRkk (ORCPT ); Fri, 16 Jun 2023 13:40:40 -0400 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4995F2943; Fri, 16 Jun 2023 10:40:39 -0700 (PDT) Received: from pps.filterd (m0279863.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 35GFpnp9009504; Fri, 16 Jun 2023 17:40:30 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=message-id : date : mime-version : subject : to : cc : references : from : in-reply-to : content-type : content-transfer-encoding; s=qcppdkim1; bh=86D5yK9haAiJoVWC5YVv/Ei6Dy+jUUyFlwwgPuERXxU=; b=azTt0rrR6miSZO4mQUCTMrf2l91Sp4lEbdwMOok4EmEXG7U19cTDasqLEeyS56YxvUIH r7MCMXuXPHNfsO4k+DFpI1abxxmH/97QeHJ8aQZ6DA4pQlrK0GD8zE18Ur+NyEdYRomB rEG51x6GGFV8UUKHmQRK3flt3Om6Wexn8Fr9cyGvrrlsOgXODRtH+PEtNK2qlYGE47Cr UCaRy17E6eJF9v9zoDnok04D4HvG5Uagx9Om1fw1Y8f40m1AFQSEaedtcl89a55GwM5Z 96p0xa3snawgRQeSY5lKkceC3SRFCsCu07R9LY3/n2D24bukUwusXDmL36QH4jHTPVkH JQ== Received: from nasanppmta02.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3r8axuj324-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 16 Jun 2023 17:40:30 +0000 Received: from nasanex01b.na.qualcomm.com (nasanex01b.na.qualcomm.com [10.46.141.250]) by NASANPPMTA02.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 35GHeTrM001451 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 16 Jun 2023 17:40:29 GMT Received: from [10.71.110.193] (10.80.80.8) by nasanex01b.na.qualcomm.com (10.46.141.250) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.42; Fri, 16 Jun 2023 10:40:29 -0700 Message-ID: <1e1eacff-7859-e704-07e1-aec8379fa55d@quicinc.com> Date: Fri, 16 Jun 2023 10:40:05 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.11.2 Subject: Re: [PATCH] drm/msm/dsi: Enable BURST_MODE for command mode for DSI 6G v1.3+ Content-Language: en-US To: Marijn Suijten CC: Rob Clark , Dmitry Baryshkov , Sean Paul , David Airlie , Daniel Vetter , , , , , References: <20230608-b4-add-burst-mode-v1-1-55dfbcfada55@quicinc.com> From: Jessica Zhang In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nasanex01b.na.qualcomm.com (10.46.141.250) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: 085KwEHL97kE7_p0XQRB9QJr4BsXhZzD X-Proofpoint-GUID: 085KwEHL97kE7_p0XQRB9QJr4BsXhZzD X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.957,Hydra:6.0.591,FMLib:17.11.176.26 definitions=2023-06-16_12,2023-06-16_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 spamscore=0 mlxscore=0 suspectscore=0 impostorscore=0 adultscore=0 bulkscore=0 priorityscore=1501 clxscore=1015 phishscore=0 lowpriorityscore=0 mlxlogscore=876 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2305260000 definitions=main-2306160159 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 6/14/2023 2:43 AM, Marijn Suijten wrote: > On 2023-06-12 16:37:36, Jessica Zhang wrote: >> During a frame transfer in command mode, there could be frequent >> LP11 <-> HS transitions when multiple DCS commands are sent mid-frame or >> if the DSI controller is running on slow clock and is throttled. To >> minimize frame latency due to these transitions, it is recommended to >> send the frame in a single burst. >> >> This feature is supported for DSI 6G 1.3 and above, thus enable burst >> mode if supported. >> >> Signed-off-by: Jessica Zhang >> --- >> drivers/gpu/drm/msm/dsi/dsi_host.c | 5 +++++ >> 1 file changed, 5 insertions(+) >> >> diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c >> index 744f2398a6d6..8254b06dca85 100644 >> --- a/drivers/gpu/drm/msm/dsi/dsi_host.c >> +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c >> @@ -994,6 +994,11 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi) >> dsi_write(msm_host, REG_DSI_CMD_MDP_STREAM0_TOTAL, >> DSI_CMD_MDP_STREAM0_TOTAL_H_TOTAL(hdisplay) | >> DSI_CMD_MDP_STREAM0_TOTAL_V_TOTAL(mode->vdisplay)); >> + >> + if (msm_host->cfg_hnd->major == MSM_DSI_VER_MAJOR_6G && >> + msm_host->cfg_hnd->minor >= MSM_DSI_6G_VER_MINOR_V1_3) >> + dsi_write(msm_host, REG_DSI_CMD_MODE_MDP_CTRL2, >> + DSI_CMD_MODE_MDP_CTRL2_BURST_MODE); > > This is not part of the timing setup, and a similar BURST_MODE flag is > enabled for video-mode in dsi_ctrl_config() - should it be moved there? Hi Marijn, Sure, I can move the change to dsi_ctrl_enable() instead. > > (There is a dsi_sw_reset() in between the calls to dsi_timing_setup() > and dsi_ctrl_cfg()) > > Note that that function sets up the CMD_CFG0 and CMD_CFG1 register, with > the former having a very similar layout to MDP_CTRL2... is there > documentation outlining the difference? I see what you mean, but unfortunately I'm not able to give you any documentation about the differences between them. FWIW, I think the macros in dsi.xml.h should give you a sense of what's within the registers and the slight differences between them. Thanks, Jessica Zhang > > - Marijn > >> } >> } >> >> >> --- >> base-commit: dd969f852ba4c66938c71889e826aa8e5300d2f2 >> change-id: 20230608-b4-add-burst-mode-a5bb144069fa >> >> Best regards, >> -- >> Jessica Zhang >>