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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Spamd-Result: default: False [-4.51 / 50.00]; BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; URIBL_BLOCKED(0.00)[suse.de:mid,suse.de:dkim,suse.de:email,suse.com:url,iscas.ac.cn:email,imap1.dmz-prg2.suse.org:helo,imap1.dmz-prg2.suse.org:rdns,bootlin.com:url]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FREEMAIL_TO(0.00)[iscas.ac.cn,loongson.cn,linux.intel.com,kernel.org,gmail.com,ffwll.ch,aosc.io,xry111.site]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; RBL_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:104:10:150:64:97:from]; RCPT_COUNT_TWELVE(0.00)[12]; FUZZY_RATELIMITED(0.00)[rspamd.com]; MIME_TRACE(0.00)[0:+]; ARC_NA(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; RCVD_TLS_ALL(0.00)[]; DKIM_TRACE(0.00)[suse.de:+]; SPAMHAUS_XBL(0.00)[2a07:de40:b281:104:10:150:64:97:from]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; MID_RHS_MATCH_FROM(0.00)[]; DNSWL_BLOCKED(0.00)[2a07:de40:b281:106:10:150:64:167:received,2a07:de40:b281:104:10:150:64:97:from]; RCVD_VIA_SMTP_AUTH(0.00)[]; RECEIVED_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:106:10:150:64:167:received]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.com:url,suse.de:mid,suse.de:dkim,suse.de:email,iscas.ac.cn:email,imap1.dmz-prg2.suse.org:helo,imap1.dmz-prg2.suse.org:rdns] X-Rspamd-Action: no action X-Spam-Flag: NO X-Spam-Score: -4.51 X-Spam-Level: X-Rspamd-Server: rspamd1.dmz-prg2.suse.org X-Rspamd-Queue-Id: ECFF94D2BA Hi Am 23.03.26 um 10:40 schrieb Icenowy Zheng: > 在 2026-03-23一的 11:40 +0800，Jianmin Lv写道： >> >> On 2026/3/21 下午5:29, Icenowy Zheng wrote: >>> 在 2026-03-21六的 17:28 +0800，Icenowy Zheng写道： >>>> As there's no known hardware capability about querying vblank on >>>> the >>>> LS7A1000 display controller, setting get_vblank_timestamp will >>>> mislead the >>>> kernel about the support of DC-backed high precision vblank >>>> query. >>>> >>>> Drop this function pointer in the CRTC function table for >>>> LS7A1000. >>>> >>>> This solves a kernel warning when booting Linux 7.0-rc3 on a >>>> Loongson-3A4000+LS7A1000 Haier Boyue G51 laptop (with injected >>>> EDID >>>> for >>>> replicating the display timing set by the firmware). >>>> >> The drm_crtc_vblank_helper_get_vblank_timestamp will call >> get_scanout_position hook to caculate timestamp, and the driver has >> get_scanout_position to support it (LS7A1000 has related register). >> So >> the get_vblank_timestamp hook is ok for LS7A1000, and we'd better >> look >> into the warning information. > The warning information is copied here: > ``` > [ 0.334960] ------------[ cut here ]------------ > [ 0.334960] WARNING: drivers/gpu/drm/drm_vblank.c:747 at > drm_crtc_vblank_helper_get_vblank_timestamp_internal+0x3c8/0x438, > CPU#0: kworker/0:1/11 > [ 0.334960] loongson 0000:00:06.1: [drm] > drm_WARN_ON_ONCE(drm_drv_uses_atomic_modeset(dev)) This is what you should investigate. mode->crtc_clock seems invalid. [1] [1] https://elixir.bootlin.com/linux/v6.19.9/source/drivers/gpu/drm/drm_vblank.c#L743 Best regards Thomas > [ 0.334960] Modules linked in: > [ 0.334960] CPU: 0 UID: 0 PID: 11 Comm: kworker/0:1 Not tainted > 7.0.0-rc4-3a4000-laptop-test+ #31 PREEMPT > [ 0.334960] Hardware name: Haier Boyue G51/Boyue G51, BIOS > K3L3A4000.HR10.200909.T 09/09/2020 > [ 0.334960] Workqueue: events drm_fb_helper_damage_work > [ 0.334960] Stack : ffffffff819dec03 0000000000000000 > 0000000000000018 9800000100223938 > [ 0.334960] 9800000100223938 9800000100223a68 > 0000000000000000 0000000000000000 > [ 0.334960] b8e8b3f2ec6b8200 98000000092bffa8 > 9800000100223768 0000000000000000 > [ 0.334960] ffffffff81632b08 0000000000000030 > ffffffff813c9530 0000000000200b20 > [ 0.334960] fffffffffffffffc 0000000000000000 > 0000000000000000 ffffffff816c1d50 > [ 0.334960] ffffffff81890000 00000000000002eb > 0000000000000000 ffffffff80c1b180 > [ 0.334960] 9800000100ff8500 0000000000000000 > 9800000005c965a8 0000000000000000 > [ 0.334960] ffffffff81a70000 9800000100220000 > 9800000100223930 0000000000000000 > [ 0.334960] ffffffff802274dc 0000000000000000 > 0000000000000000 0000000000000000 > [ 0.334960] 0000000000000000 0000000000000000 > ffffffff802274fc b8e8b3f2ec6b8200 > [ 0.334960] ... > [ 0.334960] Call Trace: > [ 0.334960] [] show_stack+0x64/0x158 > [ 0.334960] [] dump_stack_lvl+0x70/0xb0 > [ 0.334960] [] __warn+0xa8/0x120 > [ 0.334960] [] warn_slowpath_fmt+0x160/0x1f8 > [ 0.334960] [] > drm_crtc_vblank_helper_get_vblank_timestamp_internal+0x3c8/0x438 > [ 0.334960] [] > drm_crtc_get_last_vbltimestamp+0x68/0xb0 > [ 0.334960] [] drm_update_vblank_count+0xac/0x418 > [ 0.334960] [] drm_vblank_enable+0xf0/0x288 > [ 0.334960] [] drm_vblank_get+0xf8/0x160 > [ 0.334960] [] > drm_client_modeset_wait_for_vblank+0x50/0xa0 > [ 0.334960] [] > drm_fb_helper_damage_work+0x8c/0x1d8 > [ 0.334960] [] process_one_work+0x198/0x348 > [ 0.334960] [] worker_thread+0x238/0x390 > [ 0.334960] [] kthread+0x160/0x198 > [ 0.334960] [] ret_from_kernel_thread+0x14/0x1c > > [ 0.334960] ---[ end trace 0000000000000000 ]--- > ``` > >>>> Signed-off-by: Icenowy Zheng >>> Oh forgot to attach when crafting v2: >>> >>> ``` >>> Acked-by: Thomas Zimmermann >>> ``` >>> >>>> --- >>>> Changes in v2: >>>> - Re-formatted Loongson product model numbers per request from >>>> Huacai. >>>> >>>>   drivers/gpu/drm/loongson/lsdc_crtc.c | 1 - >>>>   1 file changed, 1 deletion(-) >>>> >>>> diff --git a/drivers/gpu/drm/loongson/lsdc_crtc.c >>>> b/drivers/gpu/drm/loongson/lsdc_crtc.c >>>> index 587fbe285e9ef..b3af8e0cdb15f 100644 >>>> --- a/drivers/gpu/drm/loongson/lsdc_crtc.c >>>> +++ b/drivers/gpu/drm/loongson/lsdc_crtc.c >>>> @@ -721,7 +721,6 @@ static const struct drm_crtc_funcs >>>> ls7a1000_crtc_funcs = { >>>>    .late_register = lsdc_crtc_late_register, >>>>    .enable_vblank = lsdc_crtc_enable_vblank, >>>>    .disable_vblank = lsdc_crtc_disable_vblank, >>>> - .get_vblank_timestamp = >>>> drm_crtc_vblank_helper_get_vblank_timestamp, >>>>    .atomic_print_state = lsdc_crtc_atomic_print_state, >>>>   }; >>>> -- -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)