Hi Jagan and Dave, On Wed, Dec 6, 2023 at 2:57 PM Michael Nazzareno Trimarchi <michael@xxxxxxxxxxxxxxxxxxxx> wrote: > > Hi Jagan > > On Wed, Dec 6, 2023 at 2:31 PM Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx> wrote: > > > > Hi Dario, > > > > On Wed, Dec 6, 2023 at 6:57 PM Dario Binacchi > > <dario.binacchi@xxxxxxxxxxxxxxxxxxxx> wrote: > > > > > > Hi Dave and Jagan, > > > > > > On Tue, Dec 5, 2023 at 4:39 PM Dave Stevenson > > > <dave.stevenson@xxxxxxxxxxxxxxx> wrote: > > > > > > > > Hi Dario > > > > > > > > On Tue, 5 Dec 2023 at 10:54, Dario Binacchi > > > > <dario.binacchi@xxxxxxxxxxxxxxxxxxxx> wrote: > > > > > > > > > > The patch fixes the code for finding the next bridge with the > > > > > "pre_enable_prev_first" flag set to false. In case this condition is > > > > > not verified, i. e. there is no subsequent bridge with the flag set to > > > > > false, the whole bridge list is traversed, invalidating the "next" > > > > > variable. > > > > > > > > > > The use of a new iteration variable (i. e. "iter") ensures that the value > > > > > of the "next" variable is not invalidated. > > > > > > > > We already have https://patchwork.freedesktop.org/patch/529288/ that > > > > has been reviewed (but not applied) to resolve this. What does this > > > > version do differently and why? > > > > > > My patches only affect drm_atomic_bridge_chain_post_disable(), whereas > > > Jagan's patch affects both > > > drm_atomic_bridge_chain_post_disable() and drm_atomic_bridge_chain_pre_enable(). > > > I tested Jagan's patch on my system with success and I reviewed with > > > Michael Trimarchi the > > > drm_atomic_bridge_chain_pre_enable() fixing and we think it's okay. > > > We also believe that our changes to post_disable() are better, as we > > > set the 'next' variable only when required, > > > and the code is more optimized since the list_is_last() is not called > > > within the loop. > > > Would it be possible to use Jagan's patch for fixing > > > drm_atomic_bridge_chain_pre_enable() and mine for > > > fixing drm_atomic_bridge_chain_post_disable()? > > > > > > > Can you please share the post-disabled bridge chain list with the > > below example before and after your change? > > We have already git commit the description in how the patch affects > the post_disable. As Dario > reported your patch is ok even in our use case. We don't have a real > use case as the one you describe. > > Can we know how you test it in this use case here? Can you test our > patches of post_disable? > > Thanks > Michael > > > > > Example: > > - Panel > > - Bridge 1 > > - Bridge 2 pre_enable_prev_first > > - Bridge 3 > > - Bridge 4 pre_enable_prev_first > > - Bridge 5 pre_enable_prev_first > > - Bridge 6 > > - Encoder > > > > Thanks, > > Jagan. Starting from my use case: # cat /sys/kernel/debug/dri/32e00000.lcdif/bridge_chains encoder[36] bridge[0] type: 16, ops: 0x0, OF: /soc@0/bus@32c00000/dsi@32e10000:fsl,imx8mn-mipi-dsim bridge[1] type: 16, ops: 0x8, OF: /soc@0/bus@32c00000/dsi@32e10000/panel@0:sharp,ls068b3sx0 I developed a pass through MIPI-DSI bridge driver to try to test your case: # cat /sys/kernel/debug/dri/32e00000.lcdif/bridge_chains encoder[36] bridge[0] type: 16, ops: 0x0, OF: /soc@0/bus@32c00000/dsi@32e10000:fsl,imx8mn-mipi-dsim bridge[1] type: 16, ops: 0x0, OF: /pt_mipi_dsi1:amarula,pt-mipi-dsi bridge[2] type: 16, ops: 0x0, OF: /pt_mipi_dsi2:amarula,pt-mipi-dsi bridge[3] type: 16, ops: 0x0, OF: /pt_mipi_dsi3:amarula,pt-mipi-dsi bridge[4] type: 16, ops: 0x0, OF: /pt_mipi_dsi4:amarula,pt-mipi-dsi bridge[5] type: 16, ops: 0x0, OF: /pt_mipi_dsi5:amarula,pt-mipi-dsi bridge[6] type: 16, ops: 0x8, OF: /pt_mipi_dsi5/panel@0:sharp,ls068b3sx02 The pre_enable_prev_first flag is set through the "amarula,pre_enable_prev_first" dts property I put in my dts. Your and my patches give the same results (result: OK) in both your use case and mine. But If I test my new "enlarged" use case: - Encoder - bridge[0] (samsung-dsim) - bridge[1] pre_enable_prev_first - bridge[2] pre_enable_prev_first - bridge[3] pre_enable_prev_first - bridge[4] pre_enable_prev_first - bridge[5] pre_enable_prev_first - bridge[6] pre_enable_prev_first (Panel) the result is: my patches: KO your patch: OK So, I will remove my patches from the series. Can the driver I implemented to test the use cases (pass through MIPI-DSI) be considered useful for testing these bridge pipelines? Does it make sense to send its patch? Thanks and regards Dario Dario Binacchi Senior Embedded Linux Developer dario.binacchi@xxxxxxxxxxxxxxxxxxxx __________________________________ Amarula Solutions SRL Via Le Canevare 30, 31100 Treviso, Veneto, IT T. +39 042 243 5310 info@xxxxxxxxxxxxxxxxxxxx www.amarulasolutions.com
