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[103.229.16.4]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-c76c6491fedsm16512815a12.8.2026.04.07.00.42.36 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 07 Apr 2026 00:42:40 -0700 (PDT) Message-ID: Date: Tue, 7 Apr 2026 15:42:34 +0800 Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 28/38] drm/msm/dp: add dp_mst_drm to manage DP MST bridge operations To: Dmitry Baryshkov Cc: Rob Clark , Dmitry Baryshkov , Abhinav Kumar , Jessica Zhang , Sean Paul , Marijn Suijten , David Airlie , Simona Vetter , linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, linux-kernel@vger.kernel.org, Abhinav Kumar References: <20250825-msm-dp-mst-v3-0-01faacfcdedd@oss.qualcomm.com> <20250825-msm-dp-mst-v3-28-01faacfcdedd@oss.qualcomm.com> Content-Language: en-US From: Yongxing Mou In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Proofpoint-ORIG-GUID: Evem488ZzqhAuKDLOqP7joH53xIkcRLW X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNDA3MDA2OSBTYWx0ZWRfX9BUddmFOpBc1 /F8faL5xRItzc3lvdKlLOpi7gkVd5HwTcuQvGclcSIATYa2Lej6YYbyufKxjy7+Kpuwld206+UH wR0yTJ/l81CNnSXyNlaGWt3nD2SR0p3C5jiV53aIvsb4Mzj/Ju+MImpWyYggpCMYLjVp4EE/xZR fnTVeX9e0fSWvqil6uQkPDyjPd7/Va2rPPG8YciZWK+1/JKdmzIjKV4i7O4naRBnBcznMJdm4P6 JGn5RpH1l2DFRppBH7iNK9BwRvxTxlD3RE4Hj6CNYpdcWZVYX7e8ob1iv8WNeZpV9FM3rtdEGKv 3+sEHODLaXWHo+NEvGc03AD6bIis6s6IxSG9Awep0I15xTCYqKNq+YIIbes/FXbfX/O3xHIZcit EO3aiDi+lFG4NWE+5X5FNthYEjLHxt+7OA9csS8+rxVmrDB7eGbljFUGFye6fMQTHdSua+MUGFe SxQ7cWsoNA/qaPcR+RQ== X-Authority-Analysis: v=2.4 cv=BKGDalQG c=1 sm=1 tr=0 ts=69d4b572 cx=c_pps a=UNFcQwm+pnOIJct1K4W+Mw==:117 a=nuhDOHQX5FNHPW3J6Bj6AA==:17 a=IkcTkHD0fZMA:10 a=A5OVakUREuEA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=_K5XuSEh1TEqbUxoQ0s3:22 a=COk6AnOGAAAA:8 a=EUspDBNiAAAA:8 a=EqrOjz0QqMv4gUmD5pcA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=uKXjsCUrEbL0IQVhDsJ9:22 a=TjNXssC_j7lpFel5tvFf:22 X-Proofpoint-GUID: Evem488ZzqhAuKDLOqP7joH53xIkcRLW X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-04-07_02,2026-04-03_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 phishscore=0 clxscore=1015 bulkscore=0 suspectscore=0 spamscore=0 impostorscore=0 malwarescore=0 priorityscore=1501 adultscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2604010000 definitions=main-2604070069 On 8/27/2025 1:36 AM, Dmitry Baryshkov wrote: > On Mon, Aug 25, 2025 at 10:16:14PM +0800, Yongxing Mou wrote: >> From: Abhinav Kumar >> >> Add a new file dp_mst_drm to manage the DP MST bridge operations >> similar to the dp_drm file which manages the SST bridge operations. >> Each MST encoder creates one bridge and each bridge is bound to its >> own dp_panel abstraction to manage the operations of its pipeline. >> >> Signed-off-by: Abhinav Kumar >> Signed-off-by: Yongxing Mou >> --- >> drivers/gpu/drm/msm/Makefile | 3 +- >> drivers/gpu/drm/msm/dp/dp_display.h | 3 + >> drivers/gpu/drm/msm/dp/dp_mst_drm.c | 556 ++++++++++++++++++++++++++++++++++++ >> drivers/gpu/drm/msm/dp/dp_mst_drm.h | 86 ++++++ >> 4 files changed, 647 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/msm/Makefile b/drivers/gpu/drm/msm/Makefile >> index 0c0dfb25f01b193b10946fae20138caf32cf0ed2..a61fa2637ff317ed4dee715de5d12a7befa987f5 100644 >> --- a/drivers/gpu/drm/msm/Makefile >> +++ b/drivers/gpu/drm/msm/Makefile >> @@ -142,7 +142,8 @@ msm-display-$(CONFIG_DRM_MSM_DP)+= dp/dp_aux.o \ >> dp/dp_link.o \ >> dp/dp_panel.o \ >> dp/dp_audio.o \ >> - dp/dp_utils.o >> + dp/dp_utils.o \ >> + dp/dp_mst_drm.o >> >> msm-display-$(CONFIG_DRM_MSM_HDMI_HDCP) += hdmi/hdmi_hdcp.o >> >> diff --git a/drivers/gpu/drm/msm/dp/dp_display.h b/drivers/gpu/drm/msm/dp/dp_display.h >> index d5889b801d190b6f33b180ead898c1e4ebcbf8f3..f958de6244b556df5452a5dbec6899fb79a57193 100644 >> --- a/drivers/gpu/drm/msm/dp/dp_display.h >> +++ b/drivers/gpu/drm/msm/dp/dp_display.h >> @@ -7,6 +7,7 @@ >> #define _DP_DISPLAY_H_ >> >> #include "dp_panel.h" >> +#include "dp_mst_drm.h" >> #include "disp/msm_disp_snapshot.h" >> >> #define DP_MAX_PIXEL_CLK_KHZ 675000 >> @@ -25,6 +26,8 @@ struct msm_dp { >> bool is_edp; >> bool internal_hpd; >> >> + struct msm_dp_mst *msm_dp_mst; >> + >> struct msm_dp_audio *msm_dp_audio; >> bool psr_supported; >> }; >> diff --git a/drivers/gpu/drm/msm/dp/dp_mst_drm.c b/drivers/gpu/drm/msm/dp/dp_mst_drm.c >> new file mode 100644 >> index 0000000000000000000000000000000000000000..73de29136801ef5f45e0b2d09280fe113021b68c >> --- /dev/null >> +++ b/drivers/gpu/drm/msm/dp/dp_mst_drm.c >> @@ -0,0 +1,556 @@ >> +// SPDX-License-Identifier: GPL-2.0-only >> +/* >> + * Copyright (c) 2025 Qualcomm Innovation Center, Inc. All rights reserved. >> + */ >> + >> +/* >> + * Copyright © 2014 Red Hat. > > Is it based on? Using the code? C&P? > >> + * >> + * Permission to use, copy, modify, distribute, and sell this software and its >> + * documentation for any purpose is hereby granted without fee, provided that >> + * the above copyright notice appear in all copies and that both that copyright >> + * notice and this permission notice appear in supporting documentation, and >> + * that the name of the copyright holders not be used in advertising or >> + * publicity pertaining to distribution of the software without specific, >> + * written prior permission. The copyright holders make no representations >> + * about the suitability of this software for any purpose. It is provided "as >> + * is" without express or implied warranty. >> + * >> + * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, >> + * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO >> + * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR >> + * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, >> + * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER >> + * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE >> + * OF THIS SOFTWARE. > > Why? Anyway, MIT licence would be absorbed into GPL-2.0-only (or it > should be GPL-2.0-only OR MIT) > >> + */ >> + >> +#include "dp_mst_drm.h" >> + >> +#define to_msm_dp_mst_bridge(x) container_of((x), struct msm_dp_mst_bridge, base) >> +#define to_msm_dp_mst_bridge_priv(x) \ > > Unused > >> + container_of((x), struct msm_dp_mst_bridge, obj) >> +#define to_msm_dp_mst_bridge_state_priv(x) \ > > Why is it _priv? There is no 'private' bridge state. > >> + container_of((x), struct msm_dp_mst_bridge_state, base) >> +#define to_msm_dp_mst_bridge_state(x) \ >> + to_msm_dp_mst_bridge_state_priv((x)->obj.state) >> +#define to_msm_dp_mst_connector(x) \ >> + container_of((x), struct msm_dp_mst_connector, connector) >> + >> +#define DP_MST_CONN_ID(bridge) ((bridge)->connector ? \ >> + (bridge)->connector->base.id : 0) >> + >> +#define MAX_DPCD_TRANSACTION_BYTES 16 >> + >> +static struct drm_private_state *msm_dp_mst_duplicate_bridge_state(struct drm_private_obj *obj) >> +{ >> + struct msm_dp_mst_bridge_state *mst_bridge_state; >> + >> + mst_bridge_state = kmemdup(obj->state, sizeof(*mst_bridge_state), GFP_KERNEL); >> + if (!mst_bridge_state) >> + return NULL; >> + >> + __drm_atomic_helper_private_obj_duplicate_state(obj, &mst_bridge_state->base); >> + >> + return &mst_bridge_state->base; >> +} >> + >> +static void msm_dp_mst_destroy_bridge_state(struct drm_private_obj *obj, >> + struct drm_private_state *state) >> +{ >> + struct msm_dp_mst_bridge_state *mst_bridge_state = >> + to_msm_dp_mst_bridge_state_priv(state); >> + >> + kfree(mst_bridge_state); >> +} >> + >> +static const struct drm_private_state_funcs msm_dp_mst_bridge_state_funcs = { >> + .atomic_duplicate_state = msm_dp_mst_duplicate_bridge_state, >> + .atomic_destroy_state = msm_dp_mst_destroy_bridge_state, >> +}; >> + >> +/** >> + * dp_mst_find_vcpi_slots() - Find VCPI slots for this PBN value >> + * @mgr: manager to use >> + * @pbn: payload bandwidth to convert into slots. >> + * >> + * Calculate the number of VCPI slots that will be required for the given PBN >> + * value. >> + * >> + * RETURNS: > > Return: foo, abc or def > >> + * The total slots required for this port, or error. >> + */ >> +static int msm_dp_mst_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, int pbn) >> +{ >> + int num_slots; >> + struct drm_dp_mst_topology_state *state; >> + >> + state = to_drm_dp_mst_topology_state(mgr->base.state); >> + num_slots = DIV_ROUND_UP(pbn, dfixed_trunc(state->pbn_div)); > > Don't you get those as payload->time_slots ? > Got it , will delete this. >> + >> + /* max. time slots - one slot for MTP header */ >> + if (num_slots > 63) >> + return -ENOSPC; >> + return num_slots; >> +} >> + >> +static void msm_dp_mst_update_timeslots(struct msm_dp_mst *mst, >> + struct msm_dp_mst_bridge *mst_bridge, >> + struct drm_atomic_state *state, >> + struct drm_dp_mst_port *port) >> +{ >> + int i; >> + struct msm_dp_mst_bridge *msm_dp_bridge; >> + struct drm_dp_mst_topology_state *mst_state; >> + struct drm_dp_mst_atomic_payload *payload; >> + struct msm_dp_mst_bridge_state *mst_bridge_state; >> + int prev_start = 0; >> + int prev_slots = 0; >> + >> + mst_state = to_drm_dp_mst_topology_state(mst->mst_mgr.base.state); >> + payload = drm_atomic_get_mst_payload_state(mst_state, port); >> + >> + if (!payload) { >> + DRM_ERROR("mst bridge [%d] update_timeslots failed, null payload\n", >> + mst_bridge->id); >> + return; >> + } >> + >> + for (i = 0; i < mst->max_streams; i++) { >> + msm_dp_bridge = mst->mst_bridge[i]; >> + if (mst_bridge == msm_dp_bridge) { >> + mst_bridge_state = to_msm_dp_mst_bridge_state(msm_dp_bridge); >> + /* >> + * When a payload was removed make sure to move any payloads after it >> + * to the left so all payloads are aligned to the left. >> + */ > > The comment is not valid anymore, as far as I understand. > >> + if (payload->vc_start_slot < 0) { >> + // cache the payload >> + prev_start = mst_bridge_state->start_slot; >> + prev_slots = mst_bridge_state->num_slots; >> + mst_bridge_state->pbn = 0; >> + mst_bridge_state->start_slot = 1; >> + mst_bridge_state->num_slots = 0; >> + mst_bridge_state->vcpi = 0; >> + } else { //add payload >> + mst_bridge_state->pbn = payload->pbn; >> + mst_bridge_state->start_slot = payload->vc_start_slot; >> + mst_bridge_state->num_slots = payload->time_slots; >> + mst_bridge_state->vcpi = payload->vcpi; > > I still see a lot of manual slot management here. Can't we use the > struct drm_dp_mst_atomic_payload directly instead of copying and caching > everything? > >> + } >> + } >> + } >> + >> + // Now commit all the updated payloads >> + for (i = 0; i < mst->max_streams; i++) { >> + msm_dp_bridge = mst->mst_bridge[i]; >> + >> + mst_bridge_state = to_msm_dp_mst_bridge_state(msm_dp_bridge); >> + //Shift payloads to the left if there was a removed payload. >> + if (payload->vc_start_slot < 0 && mst_bridge_state->start_slot > prev_start) >> + mst_bridge_state->start_slot -= prev_slots; > > Well... Don't MST helpers do this already for you? I see corresponding > part in drm_dp_remove_payload_part2(). > Here I wanted to reply together with the comment above. This code seems to be trying to submit the channel_info for all streams in a single commit, which is why some manual management was added. However, in the next revision I plan to remove this manual handling from the bridge state and use the payload directly instead. And after those been moved... it seems that we don't need bridge_state anymore? >> + >> + msm_dp_display_set_stream_info(mst->msm_dp, msm_dp_bridge->msm_dp_panel, >> + msm_dp_bridge->id, mst_bridge_state->start_slot, >> + mst_bridge_state->num_slots, >> + mst_bridge_state->pbn, mst_bridge_state->vcpi); >> + drm_dbg_dp(mst->msm_dp->drm_dev, >> + "conn:%d vcpi:%d start_slot:%d num_slots:%d, pbn:%d\n", >> + DP_MST_CONN_ID(msm_dp_bridge), mst_bridge_state->vcpi, >> + mst_bridge_state->start_slot, >> + mst_bridge_state->num_slots, mst_bridge_state->pbn); >> + } >> +} >> + >> +static int msm_dp_mst_bridge_pre_enable_part1(struct msm_dp_mst_bridge *dp_bridge, >> + struct drm_atomic_state *state) >> +{ >> + struct msm_dp *dp_display = dp_bridge->display; >> + struct msm_dp_mst *mst = dp_display->msm_dp_mst; >> + struct msm_dp_mst_connector *mst_conn = to_msm_dp_mst_connector(dp_bridge->connector); >> + struct drm_dp_mst_port *port = mst_conn->mst_port; >> + struct drm_dp_mst_topology_state *mst_state; >> + struct drm_dp_mst_atomic_payload *payload; >> + struct msm_dp_panel *dp_panel = mst_conn->dp_panel; >> + int pbn, slots; >> + int rc = 0; >> + >> + mst_state = drm_atomic_get_new_mst_topology_state(state, &mst->mst_mgr); >> + >> + pbn = drm_dp_calc_pbn_mode(dp_panel->msm_dp_mode.drm_mode.clock, >> + (mst_conn->connector.display_info.bpc * 3) << 4); >> + >> + slots = msm_dp_mst_find_vcpi_slots(&mst->mst_mgr, pbn); > > payload->time_slots ? > Got it. >> + >> + drm_dbg_dp(dp_display->drm_dev, "conn:%d pbn:%d, slots:%d\n", DP_MST_CONN_ID(dp_bridge), >> + pbn, slots); >> + >> + payload = drm_atomic_get_mst_payload_state(mst_state, port); >> + if (!payload || payload->time_slots <= 0) { >> + DRM_ERROR("time slots not allocated for conn:%d\n", DP_MST_CONN_ID(dp_bridge)); >> + rc = -EINVAL; >> + return rc; >> + } >> + >> + drm_dp_mst_update_slots(mst_state, DP_CAP_ANSI_8B10B); >> + >> + rc = drm_dp_add_payload_part1(&mst->mst_mgr, mst_state, payload); >> + if (rc) { >> + DRM_ERROR("payload allocation failure for conn:%d\n", DP_MST_CONN_ID(dp_bridge)); >> + return rc; >> + } >> + >> + msm_dp_mst_update_timeslots(mst, dp_bridge, state, port); >> + >> + return rc; >> +} >> + >> +static void _msm_dp_mst_bridge_pre_enable_part2(struct msm_dp_mst_bridge *dp_bridge, >> + struct drm_atomic_state *state) >> +{ >> + struct msm_dp *dp_display = dp_bridge->display; >> + struct msm_dp_mst *mst = dp_display->msm_dp_mst; >> + struct msm_dp_mst_connector *mst_conn = to_msm_dp_mst_connector(dp_bridge->connector); >> + struct drm_dp_mst_port *port = mst_conn->mst_port; >> + struct drm_dp_mst_topology_state *mst_state; >> + struct drm_dp_mst_atomic_payload *payload; >> + >> + drm_dp_check_act_status(&mst->mst_mgr); >> + >> + mst_state = to_drm_dp_mst_topology_state(mst->mst_mgr.base.state); >> + payload = drm_atomic_get_mst_payload_state(mst_state, port); >> + >> + if (!payload) { > > Kill all defensive coding. If something can not happen, there is no need > to check for it. > Got it. >> + DRM_ERROR("mst bridge [%d] null payload\n", dp_bridge->id); >> + return; >> + } >> + >> + if (!payload->port) { >> + DRM_ERROR("mst bridge [%d] null port\n", dp_bridge->id); >> + return; >> + } >> + >> + if (!payload->port->connector) { >> + DRM_ERROR("mst bridge [%d] part-2 failed, null connector\n", >> + dp_bridge->id); >> + return; >> + } >> + >> + if (payload->vc_start_slot == -1) { >> + DRM_ERROR("mst bridge [%d] part-2 failed, payload alloc part 1 failed\n", >> + dp_bridge->id); >> + return; >> + } >> + >> + drm_dp_add_payload_part2(&mst->mst_mgr, payload); >> + >> + drm_dbg_dp(dp_display->drm_dev, "mst bridge [%d] _pre enable part-2 complete\n", >> + dp_bridge->id); >> +} >> + >> +static void msm_dp_mst_bridge_pre_disable_part1(struct msm_dp_mst_bridge *dp_bridge, >> + struct drm_atomic_state *state) >> +{ >> + struct msm_dp *dp_display = dp_bridge->display; >> + struct msm_dp_mst *mst = dp_display->msm_dp_mst; >> + struct msm_dp_mst_connector *mst_conn = to_msm_dp_mst_connector(dp_bridge->connector); >> + struct drm_dp_mst_port *port = mst_conn->mst_port; >> + struct drm_dp_mst_topology_state *old_mst_state; >> + struct drm_dp_mst_topology_state *new_mst_state; >> + const struct drm_dp_mst_atomic_payload *old_payload; >> + struct drm_dp_mst_atomic_payload *new_payload; >> + >> + old_mst_state = drm_atomic_get_old_mst_topology_state(state, &mst->mst_mgr); >> + >> + new_mst_state = drm_atomic_get_new_mst_topology_state(state, &mst->mst_mgr); >> + >> + old_payload = drm_atomic_get_mst_payload_state(old_mst_state, port); >> + new_payload = drm_atomic_get_mst_payload_state(new_mst_state, port); >> + >> + if (!old_payload || !new_payload) { >> + DRM_ERROR("mst bridge [%d] _pre disable part-1 failed, null payload\n", >> + dp_bridge->id); >> + return; >> + } >> + >> + drm_dp_remove_payload_part1(&mst->mst_mgr, new_mst_state, new_payload); >> + drm_dp_remove_payload_part2(&mst->mst_mgr, new_mst_state, old_payload, new_payload); >> + >> + msm_dp_mst_update_timeslots(mst, dp_bridge, state, port); >> + >> + drm_dbg_dp(dp_display->drm_dev, "mst bridge [%d] _pre disable part-1 complete\n", >> + dp_bridge->id); >> +} >> + >> +static void msm_dp_mst_bridge_atomic_pre_enable(struct drm_bridge *drm_bridge, >> + struct drm_atomic_state *state) >> +{ >> + int rc = 0; >> + struct msm_dp_mst_bridge *bridge; >> + struct msm_dp *dp_display; >> + struct msm_dp_mst_bridge_state *mst_bridge_state; >> + struct msm_dp_mst *dp_mst; >> + >> + if (!drm_bridge) { >> + DRM_ERROR("Invalid params\n"); >> + return; >> + } >> + >> + bridge = to_msm_dp_mst_bridge(drm_bridge); >> + mst_bridge_state = to_msm_dp_mst_bridge_state(bridge); >> + dp_display = bridge->display; >> + dp_mst = dp_display->msm_dp_mst; >> + >> + /* to cover cases of bridge_disable/bridge_enable without modeset */ >> + bridge->connector = mst_bridge_state->connector; >> + bridge->msm_dp_panel = mst_bridge_state->msm_dp_panel; >> + >> + if (!bridge->connector) { >> + DRM_ERROR("Invalid connector\n"); >> + return; >> + } >> + >> + mutex_lock(&dp_mst->mst_lock); >> + msm_dp_display_atomic_prepare(dp_display); >> + >> + rc = msm_dp_mst_bridge_pre_enable_part1(bridge, state); >> + if (rc) { >> + DRM_ERROR("[%d] DP display pre-enable failed, rc=%d\n", bridge->id, rc); >> + msm_dp_display_unprepare(dp_display); >> + mutex_unlock(&dp_mst->mst_lock); >> + return; >> + } >> + >> + msm_dp_display_enable_helper(dp_display, bridge->msm_dp_panel); >> + >> + _msm_dp_mst_bridge_pre_enable_part2(bridge, state); >> + >> + mutex_unlock(&dp_mst->mst_lock); >> + >> + drm_dbg_dp(dp_display->drm_dev, "conn:%d mode:%s fps:%d vcpi:%d slots:%d to %d\n", >> + DP_MST_CONN_ID(bridge), bridge->msm_dp_panel->msm_dp_mode.drm_mode.name, >> + drm_mode_vrefresh(&bridge->msm_dp_panel->msm_dp_mode.drm_mode), >> + mst_bridge_state->vcpi, mst_bridge_state->start_slot, >> + mst_bridge_state->start_slot + mst_bridge_state->num_slots); >> +} >> + >> +static void msm_dp_mst_bridge_atomic_disable(struct drm_bridge *drm_bridge, >> + struct drm_atomic_state *state) >> +{ >> + struct msm_dp_mst_bridge *bridge; >> + struct msm_dp *dp_display; >> + struct msm_dp_mst *mst; >> + >> + if (!drm_bridge) { >> + DRM_ERROR("Invalid params\n"); >> + return; >> + } >> + >> + bridge = to_msm_dp_mst_bridge(drm_bridge); >> + if (!bridge->connector) { >> + DRM_ERROR("Invalid connector\n"); >> + return; >> + } >> + >> + dp_display = bridge->display; >> + mst = dp_display->msm_dp_mst; >> + >> + mutex_lock(&mst->mst_lock); >> + >> + msm_dp_mst_bridge_pre_disable_part1(bridge, state); >> + >> + msm_dp_display_disable_helper(dp_display, bridge->msm_dp_panel); >> + >> + drm_dp_check_act_status(&mst->mst_mgr); >> + >> + mutex_unlock(&mst->mst_lock); >> + >> + drm_dbg_dp(dp_display->drm_dev, "mst bridge:%d conn:%d disable complete\n", bridge->id, >> + DP_MST_CONN_ID(bridge)); >> +} >> + >> +static void msm_dp_mst_bridge_atomic_post_disable(struct drm_bridge *drm_bridge, >> + struct drm_atomic_state *state) >> +{ >> + int conn = 0; >> + struct msm_dp_mst_bridge *bridge; >> + struct msm_dp *dp_display; >> + struct msm_dp_mst *mst; >> + >> + if (!drm_bridge) { >> + DRM_ERROR("Invalid params\n"); >> + return; >> + } >> + >> + bridge = to_msm_dp_mst_bridge(drm_bridge); >> + if (!bridge->connector) { >> + DRM_ERROR("Invalid connector\n"); >> + return; >> + } >> + >> + conn = DP_MST_CONN_ID(bridge); >> + >> + dp_display = bridge->display; >> + mst = dp_display->msm_dp_mst; >> + >> + mutex_lock(&mst->mst_lock); >> + >> + msm_dp_display_atomic_post_disable_helper(dp_display, bridge->msm_dp_panel); >> + >> + if (!dp_display->mst_active) >> + msm_dp_display_unprepare(dp_display); >> + >> + bridge->connector = NULL; >> + bridge->msm_dp_panel = NULL; >> + >> + mutex_unlock(&mst->mst_lock); >> + >> + drm_dbg_dp(dp_display->drm_dev, "mst bridge:%d conn:%d post disable complete\n", >> + bridge->id, conn); >> +} >> + >> +static int msm_dp_mst_bridge_atomic_check(struct drm_bridge *drm_bridge, >> + struct drm_bridge_state *bridge_state, >> + struct drm_crtc_state *crtc_state, >> + struct drm_connector_state *conn_state) >> +{ >> + struct drm_atomic_state *state = crtc_state->state; >> + struct drm_connector *connector = conn_state->connector; >> + struct drm_dp_mst_topology_state *mst_state; >> + struct msm_dp_mst_connector *mst_conn; >> + struct msm_dp *dp_display; >> + struct msm_dp_mst *mst; >> + int rc = 0, pbn, slots; >> + u32 bpp; >> + >> + if (!drm_atomic_crtc_needs_modeset(crtc_state) || !crtc_state->enable) { >> + return 0; >> + } >> + >> + mst_conn = to_msm_dp_mst_connector(connector); >> + dp_display = mst_conn->msm_dp; >> + mst = dp_display->msm_dp_mst; >> + >> + bpp = connector->display_info.bpc * 3; >> + >> + if (!bpp) >> + bpp = 24; >> + >> + pbn = drm_dp_calc_pbn_mode(crtc_state->mode.clock, bpp << 4); >> + >> + mst_state = to_drm_dp_mst_topology_state(mst->mst_mgr.base.state); >> + if (IS_ERR(mst_state)) >> + return PTR_ERR(mst_state); >> + >> + if (!dfixed_trunc(mst_state->pbn_div)) { >> + mst_state->pbn_div = >> + drm_dp_get_vc_payload_bw(mst_conn->dp_panel->link_info.rate, >> + mst_conn->dp_panel->link_info.num_lanes); >> + } >> + >> + slots = drm_dp_atomic_find_time_slots(state, &mst->mst_mgr, mst_conn->mst_port, pbn); >> + >> + drm_dbg_dp(dp_display->drm_dev, "add slots, conn:%d pbn:%d slots:%d rc:%d\n", >> + connector->base.id, pbn, slots, rc); >> + >> + return 0; >> +} >> + >> +static void msm_dp_mst_bridge_mode_set(struct drm_bridge *drm_bridge, >> + const struct drm_display_mode *mode, >> + const struct drm_display_mode *adjusted_mode) > > It's clearly defined as deprecated, not to be used by new drivers. Any > reason for not following it? > Will delete this. >> +{ >> + struct msm_dp_mst_bridge *bridge; >> + struct msm_dp_mst_bridge_state *mst_bridge_state; >> + struct msm_dp *dp_display; >> + struct msm_dp_panel *msm_dp_panel; >> + >> + if (!drm_bridge || !mode || !adjusted_mode) { > > Ugh. No overprotective coding. > Got it. >> + DRM_ERROR("Invalid params\n"); >> + return; >> + } >> + >> + bridge = to_msm_dp_mst_bridge(drm_bridge); >> + >> + mst_bridge_state = to_msm_dp_mst_bridge_state(bridge); >> + bridge->connector = mst_bridge_state->connector; >> + bridge->msm_dp_panel = mst_bridge_state->msm_dp_panel; > > Why? All important functions should have access to bridge state and thus state fields. > >> + >> + msm_dp_panel = bridge->msm_dp_panel; >> + dp_display = bridge->display; >> + >> + msm_dp_display_mode_set_helper(dp_display, mode, adjusted_mode, bridge->msm_dp_panel); >> + msm_dp_panel->pbn = drm_dp_calc_pbn_mode(msm_dp_panel->msm_dp_mode.drm_mode.clock, >> + (msm_dp_panel->msm_dp_mode.bpp << 4)); >> + drm_dbg_dp(dp_display->drm_dev, "mst bridge:%d conn:%d mode set complete %s\n", bridge->id, >> + DP_MST_CONN_ID(bridge), mode->name); >> +} >> + >> +/* DP MST Bridge APIs */ >> +static const struct drm_bridge_funcs msm_dp_mst_bridge_ops = { >> + .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, >> + .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, >> + .atomic_reset = drm_atomic_helper_bridge_reset, >> + .atomic_pre_enable = msm_dp_mst_bridge_atomic_pre_enable, >> + .atomic_disable = msm_dp_mst_bridge_atomic_disable, >> + .atomic_post_disable = msm_dp_mst_bridge_atomic_post_disable, >> + .atomic_check = msm_dp_mst_bridge_atomic_check, >> + .mode_set = msm_dp_mst_bridge_mode_set, >> +}; >> + >> +int msm_dp_mst_drm_bridge_init(struct msm_dp *dp_display, struct drm_encoder *encoder) >> +{ >> + int rc = 0; >> + struct msm_dp_mst_bridge *bridge = NULL; >> + struct msm_dp_mst_bridge_state *mst_bridge_state; >> + struct drm_device *dev; >> + struct msm_dp_mst *mst = dp_display->msm_dp_mst; >> + int i; >> + >> + for (i = 0; i < mst->max_streams; i++) { >> + if (!mst->mst_bridge[i]->in_use) { >> + bridge = mst->mst_bridge[i]; >> + bridge->encoder = encoder; >> + bridge->in_use = true; >> + bridge->id = i; >> + break; >> + } >> + } >> + >> + if (i == mst->max_streams) { >> + DRM_ERROR("mst supports only %d bridges\n", i); >> + rc = -EACCES; >> + goto end; >> + } >> + >> + dev = dp_display->drm_dev; >> + bridge->display = dp_display; >> + bridge->base.funcs = &msm_dp_mst_bridge_ops; >> + bridge->base.encoder = encoder; >> + bridge->base.type = dp_display->connector_type; >> + bridge->base.ops = DRM_BRIDGE_OP_MODES; >> + drm_bridge_add(&bridge->base); >> + >> + rc = drm_bridge_attach(encoder, &bridge->base, NULL, 0); >> + if (rc) { >> + DRM_ERROR("failed to attach bridge, rc=%d\n", rc); >> + goto end; >> + } >> + >> + mst_bridge_state = kzalloc(sizeof(*mst_bridge_state), GFP_KERNEL); >> + if (!mst_bridge_state) { >> + rc = -ENOMEM; >> + goto end; >> + } >> + >> + drm_atomic_private_obj_init(dev, &bridge->obj, >> + &mst_bridge_state->base, >> + &msm_dp_mst_bridge_state_funcs); > > Why do you register a separate object if you already have bridge and you > can use bridge's state? > >> + >> + drm_dbg_dp(dp_display->drm_dev, "mst drm bridge init. bridge id:%d\n", i); >> + >> + return 0; >> + >> +end: >> + return rc; >> +} >> diff --git a/drivers/gpu/drm/msm/dp/dp_mst_drm.h b/drivers/gpu/drm/msm/dp/dp_mst_drm.h >> new file mode 100644 >> index 0000000000000000000000000000000000000000..d75731ca2e5870377026e8ad1057bdcc5f0d4c78 >> --- /dev/null >> +++ b/drivers/gpu/drm/msm/dp/dp_mst_drm.h >> @@ -0,0 +1,86 @@ >> +/* SPDX-License-Identifier: GPL-2.0-only */ >> +/* >> + * Copyright (c) 2025 Qualcomm Innovation Center, Inc. All rights reserved. >> + * >> + * Permission to use, copy, modify, distribute, and sell this software and its >> + * documentation for any purpose is hereby granted without fee, provided that >> + * the above copyright notice appear in all copies and that both that copyright >> + * notice and this permission notice appear in supporting documentation, and >> + * that the name of the copyright holders not be used in advertising or >> + * publicity pertaining to distribution of the software without specific, >> + * written prior permission. The copyright holders make no representations >> + * about the suitability of this software for any purpose. It is provided "as >> + * is" without express or implied warranty. >> + * >> + * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, >> + * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO >> + * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR >> + * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, >> + * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER >> + * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE >> + * OF THIS SOFTWARE. > > Please check what you are sending. The SPDX header says GPL-2.0-only, > while the licence text is MIT. Why? > >> + */ >> + >> +#ifndef _DP_MST_DRM_H_ >> +#define _DP_MST_DRM_H_ >> + >> +#include >> +#include >> +#include >> +#include >> + >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include > > Are all those includes necessary here? Replace them with forward struct > definitions and move includes to the source file. Only keep those, which > are actually necessary for the contents of the header. > >> + >> +#include "dp_panel.h" >> +#include "dp_display.h" >> + >> +struct msm_dp_mst_bridge { >> + struct drm_bridge base; >> + struct drm_private_obj obj; >> + u32 id; >> + >> + bool in_use; > > What does it mean? In use currently for one of outputs? > >> + >> + struct msm_dp *display; >> + struct drm_encoder *encoder; >> + >> + struct drm_connector *connector; > > Why do you have connector both as a part of the bridge and bridge state? > > Please describe design decisions in the commit mesage or as comments. > Sure will add it in commit message. >> + struct msm_dp_panel *msm_dp_panel; >> +}; >> + >> +struct msm_dp_mst_bridge_state { >> + struct drm_private_state base; >> + struct drm_connector *connector; >> + struct msm_dp_panel *msm_dp_panel; >> + >> + int vcpi; >> + int pbn; >> + int num_slots; >> + int start_slot; > > I'd definitely prefer to have payload pointer here, if that's also a > part of the state. > Here if we not need pbn/vcpi/slots/start_slot in bridge state, can we delete whole bridge state and move connector/dp_panel to bridge? >> +}; >> + >> +struct msm_dp_mst { >> + struct drm_dp_mst_topology_mgr mst_mgr; >> + struct msm_dp_mst_bridge *mst_bridge[DP_STREAM_MAX]; >> + struct msm_dp *msm_dp; >> + u32 max_streams; >> + struct mutex mst_lock; >> +}; >> + >> +struct msm_dp_mst_connector { >> + struct drm_connector connector; >> + struct drm_dp_mst_port *mst_port; >> + struct msm_dp *msm_dp; >> + struct msm_dp_panel *dp_panel; >> +}; >> + >> +int msm_dp_mst_drm_bridge_init(struct msm_dp *dp, struct drm_encoder *encoder); >> + >> +#endif /* _DP_MST_DRM_H_ */ >> >> -- >> 2.34.1 >> >