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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Level: X-Rspamd-Action: no action X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Rspamd-Queue-Id: 9A7501FE21 X-Spamd-Result: default: False [-3.01 / 50.00]; BAYES_HAM(-3.00)[100.00%]; SUSPICIOUS_RECIPS(1.50)[]; 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)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FREEMAIL_TO(0.00)[oss.qualcomm.com,synopsys.com,linux.intel.com,kernel.org,gmail.com,ffwll.ch,jms.id.au,codeconstruct.com.au,nxp.com,pengutronix.de,epam.com]; ARC_NA(0.00)[]; RBL_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:104:10:150:64:97:from]; RCPT_COUNT_TWELVE(0.00)[25]; MIME_TRACE(0.00)[0:+]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; RCVD_TLS_ALL(0.00)[]; DKIM_TRACE(0.00)[suse.de:+]; RCVD_COUNT_TWO(0.00)[2]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; TAGGED_RCPT(0.00)[]; RECEIVED_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:106:10:150:64:167:received]; RCVD_VIA_SMTP_AUTH(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.com:url,suse.de:dkim,suse.de:email,suse.de:mid,imap1.dmz-prg2.suse.org:rdns,imap1.dmz-prg2.suse.org:helo,qualcomm.com:email] X-Spam-Flag: NO X-Spam-Score: -3.01 Hi Am 26.07.26 um 21:42 schrieb Ze Huang: > The simple-KMS helper calls the pipe update after enabling the CRTC. > On an enable commit, imx_lcdc_pipe_enable() already programs the > mode and enables clk_per. The following pipe update sees the plane move > from no CRTC to the active CRTC, treats it as a mode update, and calls > imx_lcdc_update_hw_registers() again. > > That second call has no old CRTC state to disable clk_per first, but it > enables clk_per again at the end. The disable path only drops one > reference, leaving clk_per enabled after each on/off cycle. > > Skip the register update from the pipe update path when the CRTC already > needs a modeset. The enable path has already programmed the hardware for > that commit; keep the event handling in pipe update unchanged. That seems reasonable. Once the driver uses regular DRM helpers instead of simple_kms, it can all be untangled and this test won't be necessary any longer. > > Fixes: c87e859cdeb5 ("drm/imx/lcdc: Implement DRM driver for imx25") > Signed-off-by: Ze Huang Acked-by: Thomas Zimmermann > --- > drivers/gpu/drm/imx/lcdc/imx-lcdc.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/imx/lcdc/imx-lcdc.c b/drivers/gpu/drm/imx/lcdc/imx-lcdc.c > index f52832b43aca..81024f7d9e96 100644 > --- a/drivers/gpu/drm/imx/lcdc/imx-lcdc.c > +++ b/drivers/gpu/drm/imx/lcdc/imx-lcdc.c > @@ -311,7 +311,8 @@ static void imx_lcdc_pipe_update(struct drm_simple_display_pipe *pipe, > else if (old_crtc != crtc) > mode_changed = true; > > - imx_lcdc_update_hw_registers(pipe, old_state, mode_changed); > + if (!drm_atomic_crtc_needs_modeset(crtc->state)) > + imx_lcdc_update_hw_registers(pipe, old_state, mode_changed); > > if (event) { > crtc->state->event = NULL; > -- -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com GF: Jochen Jaser, Andrew McDonald, (HRB 36809, AG Nürnberg)