| Message ID | 20190829060550.62095-1-john.stultz@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [RFC] drm: kirin: Fix dsi probe/attach logic | expand |
On 29.08.2019 08:05, John Stultz wrote: > Since commit 83f35bc3a852 ("drm/bridge: adv7511: Attach to DSI > host at probe time") landed in -next the HiKey board would fail > to boot, looping: > > adv7511 2-0039: failed to find dsi host > > messages over and over. Andrzej Hajda suggested this is due to a > circular dependency issue, and that the adv7511 change is > correcting the improper order used earlier. > > Unfortunately this means the DSI drivers that use adv7511 need > to also need to be updated to use the proper ordering to > continue to work. > > This patch tries to reorder the initialization to register the > dsi_host first, and then call component_add via dsi_host_attach, > instead of doing that at probe time. > > This seems to resolve the issue with the HiKey board. > > Cc: Andrzej Hajda <a.hajda@samsung.com> > Cc: Matt Redfearn <matt.redfearn@thinci.com> > Cc: Xinliang Liu <z.liuxinliang@hisilicon.com> > Cc: Rongrong Zou <zourongrong@gmail.com> > Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com> > Cc: Neil Armstrong <narmstrong@baylibre.com> > Cc: Jonas Karlman <jonas@kwiboo.se> > Cc: Jernej Skrabec <jernej.skrabec@siol.net> > Cc: Thierry Reding <thierry.reding@gmail.com> > Cc: David Airlie <airlied@linux.ie>, > Cc: Sean Paul <seanpaul@chromium.org> > Cc: Sam Ravnborg <sam@ravnborg.org> > Cc: "dri-devel@lists.freedesktop.org" <dri-devel@lists.freedesktop.org> > Fixes: 83f35bc3a852 ("drm/bridge: adv7511: Attach to DSI host at probe time") > Signed-off-by: John Stultz <john.stultz@linaro.org> > --- > Note: I'm really not super familiar with the DSI code here, > and am mostly just trying to refactor the existing code in a > similar fashion to the suggested dw-mipi-dsi-rockchip.c > implementation. Careful review would be greatly appreciated! > > Also there is an outstanding regression on the db410c since it > similarly uses the adv7511 and probably needs a similar rework. > --- > drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c | 111 ++++++++++--------- > 1 file changed, 56 insertions(+), 55 deletions(-) > > diff --git a/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c b/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c > index 5bf8138941de..696cee1a1219 100644 > --- a/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c > +++ b/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c > @@ -79,6 +79,7 @@ struct dsi_hw_ctx { > }; > > struct dw_dsi { > + struct device *dev; > struct drm_encoder encoder; > struct drm_bridge *bridge; > struct mipi_dsi_host host; > @@ -724,51 +725,6 @@ static int dw_drm_encoder_init(struct device *dev, > return 0; > } > > -static int dsi_host_attach(struct mipi_dsi_host *host, > - struct mipi_dsi_device *mdsi) > -{ > - struct dw_dsi *dsi = host_to_dsi(host); > - > - if (mdsi->lanes < 1 || mdsi->lanes > 4) { > - DRM_ERROR("dsi device params invalid\n"); > - return -EINVAL; > - } > - > - dsi->lanes = mdsi->lanes; > - dsi->format = mdsi->format; > - dsi->mode_flags = mdsi->mode_flags; > - > - return 0; > -} > - > -static int dsi_host_detach(struct mipi_dsi_host *host, > - struct mipi_dsi_device *mdsi) > -{ > - /* do nothing */ > - return 0; > -} > - > -static const struct mipi_dsi_host_ops dsi_host_ops = { > - .attach = dsi_host_attach, > - .detach = dsi_host_detach, > -}; > - > -static int dsi_host_init(struct device *dev, struct dw_dsi *dsi) > -{ > - struct mipi_dsi_host *host = &dsi->host; > - int ret; > - > - host->dev = dev; > - host->ops = &dsi_host_ops; > - ret = mipi_dsi_host_register(host); > - if (ret) { > - DRM_ERROR("failed to register dsi host\n"); > - return ret; > - } > - > - return 0; > -} > - > static int dsi_bridge_init(struct drm_device *dev, struct dw_dsi *dsi) > { > struct drm_encoder *encoder = &dsi->encoder; > @@ -796,10 +752,6 @@ static int dsi_bind(struct device *dev, struct device *master, void *data) > if (ret) > return ret; > > - ret = dsi_host_init(dev, dsi); > - if (ret) > - return ret; > - > ret = dsi_bridge_init(drm_dev, dsi); > if (ret) > return ret; > @@ -817,13 +769,22 @@ static const struct component_ops dsi_ops = { > .unbind = dsi_unbind, > }; > > -static int dsi_parse_dt(struct platform_device *pdev, struct dw_dsi *dsi) > +static int dsi_host_attach(struct mipi_dsi_host *host, > + struct mipi_dsi_device *mdsi) > { > - struct dsi_hw_ctx *ctx = dsi->ctx; > - struct device_node *np = pdev->dev.of_node; > - struct resource *res; > + struct dw_dsi *dsi = host_to_dsi(host); > + struct device_node *np = dsi->dev->of_node; > int ret; > > + if (mdsi->lanes < 1 || mdsi->lanes > 4) { > + DRM_ERROR("dsi device params invalid\n"); > + return -EINVAL; > + } > + > + dsi->lanes = mdsi->lanes; > + dsi->format = mdsi->format; > + dsi->mode_flags = mdsi->mode_flags; > + > /* > * Get the endpoint node. In our case, dsi has one output port1 > * to which the external HDMI bridge is connected. > @@ -832,6 +793,42 @@ static int dsi_parse_dt(struct platform_device *pdev, struct dw_dsi *dsi) > if (ret) > return ret; > > + return component_add(dsi->dev, &dsi_ops); > +} > + > +static int dsi_host_detach(struct mipi_dsi_host *host, > + struct mipi_dsi_device *mdsi) > +{ > + /* do nothing */ > + return 0; > +} > + > +static const struct mipi_dsi_host_ops dsi_host_ops = { > + .attach = dsi_host_attach, > + .detach = dsi_host_detach, > +}; > + > +static int dsi_host_init(struct device *dev, struct dw_dsi *dsi) > +{ > + struct mipi_dsi_host *host = &dsi->host; > + int ret; > + > + host->dev = dev; > + host->ops = &dsi_host_ops; > + ret = mipi_dsi_host_register(host); > + if (ret) { > + DRM_ERROR("failed to register dsi host\n"); > + return ret; > + } > + > + return 0; > +} > + > +static int dsi_parse_dt(struct platform_device *pdev, struct dw_dsi *dsi) > +{ > + struct dsi_hw_ctx *ctx = dsi->ctx; > + struct resource *res; > + > ctx->pclk = devm_clk_get(&pdev->dev, "pclk"); > if (IS_ERR(ctx->pclk)) { > DRM_ERROR("failed to get pclk clock\n"); > @@ -862,15 +859,19 @@ static int dsi_probe(struct platform_device *pdev) > } > dsi = &data->dsi; > ctx = &data->ctx; > + dsi->dev = &pdev->dev; > dsi->ctx = ctx; > > ret = dsi_parse_dt(pdev, dsi); > if (ret) > return ret; > > - platform_set_drvdata(pdev, data); > + ret = dsi_host_init(&pdev->dev, dsi); > + if (ret) > + return ret; > > - return component_add(&pdev->dev, &dsi_ops); > + platform_set_drvdata(pdev, data); I suspect platform_set_drvdata should be before dsi_host_init. Imagine dsi_probe calls dsi_host_init it registers dsi_host and instantly dsi_device appears, so dsi_host_attach is called, it calls component_add and dsi_bind is called, which requires valid drvdata. Beside this it looks correct, but it would be good to test it. So after fixing above you can add my R-B. Regards Andrzej > + return 0; > } > > static int dsi_remove(struct platform_device *pdev)
On Wed, Aug 28, 2019 at 11:06 PM John Stultz <john.stultz@linaro.org> wrote: > > Since commit 83f35bc3a852 ("drm/bridge: adv7511: Attach to DSI > host at probe time") landed in -next the HiKey board would fail > to boot, looping: No, please revert 83f35bc3a852.. that is going in the *complete* wrong direction. We actually should be moving panels to not require dsi host until attach time, similar to how bridges work, not the other way around. The problem is that, when dealing with bootloader enabled display, we need to be really careful not to touch the hardware until the display driver knows the bridge/panel is present. If the bridge/panel probes after the display driver, we could end up killing scanout (efifb/simplefb).. if the bridge/panel is missing some dependency and never probes, it is rather unpleasant to be stuck trying to debug what went wrong with no display. Sorry I didn't notice that adv7511 patch before it landed, but the right thing to do now is to revert it. BR, -R > adv7511 2-0039: failed to find dsi host > > messages over and over. Andrzej Hajda suggested this is due to a > circular dependency issue, and that the adv7511 change is > correcting the improper order used earlier. > > Unfortunately this means the DSI drivers that use adv7511 need > to also need to be updated to use the proper ordering to > continue to work. > > This patch tries to reorder the initialization to register the > dsi_host first, and then call component_add via dsi_host_attach, > instead of doing that at probe time. > > This seems to resolve the issue with the HiKey board. > > Cc: Andrzej Hajda <a.hajda@samsung.com> > Cc: Matt Redfearn <matt.redfearn@thinci.com> > Cc: Xinliang Liu <z.liuxinliang@hisilicon.com> > Cc: Rongrong Zou <zourongrong@gmail.com> > Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com> > Cc: Neil Armstrong <narmstrong@baylibre.com> > Cc: Jonas Karlman <jonas@kwiboo.se> > Cc: Jernej Skrabec <jernej.skrabec@siol.net> > Cc: Thierry Reding <thierry.reding@gmail.com> > Cc: David Airlie <airlied@linux.ie>, > Cc: Sean Paul <seanpaul@chromium.org> > Cc: Sam Ravnborg <sam@ravnborg.org> > Cc: "dri-devel@lists.freedesktop.org" <dri-devel@lists.freedesktop.org> > Fixes: 83f35bc3a852 ("drm/bridge: adv7511: Attach to DSI host at probe time") > Signed-off-by: John Stultz <john.stultz@linaro.org> > --- > Note: I'm really not super familiar with the DSI code here, > and am mostly just trying to refactor the existing code in a > similar fashion to the suggested dw-mipi-dsi-rockchip.c > implementation. Careful review would be greatly appreciated! > > Also there is an outstanding regression on the db410c since it > similarly uses the adv7511 and probably needs a similar rework. > --- > drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c | 111 ++++++++++--------- > 1 file changed, 56 insertions(+), 55 deletions(-) > > diff --git a/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c b/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c > index 5bf8138941de..696cee1a1219 100644 > --- a/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c > +++ b/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c > @@ -79,6 +79,7 @@ struct dsi_hw_ctx { > }; > > struct dw_dsi { > + struct device *dev; > struct drm_encoder encoder; > struct drm_bridge *bridge; > struct mipi_dsi_host host; > @@ -724,51 +725,6 @@ static int dw_drm_encoder_init(struct device *dev, > return 0; > } > > -static int dsi_host_attach(struct mipi_dsi_host *host, > - struct mipi_dsi_device *mdsi) > -{ > - struct dw_dsi *dsi = host_to_dsi(host); > - > - if (mdsi->lanes < 1 || mdsi->lanes > 4) { > - DRM_ERROR("dsi device params invalid\n"); > - return -EINVAL; > - } > - > - dsi->lanes = mdsi->lanes; > - dsi->format = mdsi->format; > - dsi->mode_flags = mdsi->mode_flags; > - > - return 0; > -} > - > -static int dsi_host_detach(struct mipi_dsi_host *host, > - struct mipi_dsi_device *mdsi) > -{ > - /* do nothing */ > - return 0; > -} > - > -static const struct mipi_dsi_host_ops dsi_host_ops = { > - .attach = dsi_host_attach, > - .detach = dsi_host_detach, > -}; > - > -static int dsi_host_init(struct device *dev, struct dw_dsi *dsi) > -{ > - struct mipi_dsi_host *host = &dsi->host; > - int ret; > - > - host->dev = dev; > - host->ops = &dsi_host_ops; > - ret = mipi_dsi_host_register(host); > - if (ret) { > - DRM_ERROR("failed to register dsi host\n"); > - return ret; > - } > - > - return 0; > -} > - > static int dsi_bridge_init(struct drm_device *dev, struct dw_dsi *dsi) > { > struct drm_encoder *encoder = &dsi->encoder; > @@ -796,10 +752,6 @@ static int dsi_bind(struct device *dev, struct device *master, void *data) > if (ret) > return ret; > > - ret = dsi_host_init(dev, dsi); > - if (ret) > - return ret; > - > ret = dsi_bridge_init(drm_dev, dsi); > if (ret) > return ret; > @@ -817,13 +769,22 @@ static const struct component_ops dsi_ops = { > .unbind = dsi_unbind, > }; > > -static int dsi_parse_dt(struct platform_device *pdev, struct dw_dsi *dsi) > +static int dsi_host_attach(struct mipi_dsi_host *host, > + struct mipi_dsi_device *mdsi) > { > - struct dsi_hw_ctx *ctx = dsi->ctx; > - struct device_node *np = pdev->dev.of_node; > - struct resource *res; > + struct dw_dsi *dsi = host_to_dsi(host); > + struct device_node *np = dsi->dev->of_node; > int ret; > > + if (mdsi->lanes < 1 || mdsi->lanes > 4) { > + DRM_ERROR("dsi device params invalid\n"); > + return -EINVAL; > + } > + > + dsi->lanes = mdsi->lanes; > + dsi->format = mdsi->format; > + dsi->mode_flags = mdsi->mode_flags; > + > /* > * Get the endpoint node. In our case, dsi has one output port1 > * to which the external HDMI bridge is connected. > @@ -832,6 +793,42 @@ static int dsi_parse_dt(struct platform_device *pdev, struct dw_dsi *dsi) > if (ret) > return ret; > > + return component_add(dsi->dev, &dsi_ops); > +} > + > +static int dsi_host_detach(struct mipi_dsi_host *host, > + struct mipi_dsi_device *mdsi) > +{ > + /* do nothing */ > + return 0; > +} > + > +static const struct mipi_dsi_host_ops dsi_host_ops = { > + .attach = dsi_host_attach, > + .detach = dsi_host_detach, > +}; > + > +static int dsi_host_init(struct device *dev, struct dw_dsi *dsi) > +{ > + struct mipi_dsi_host *host = &dsi->host; > + int ret; > + > + host->dev = dev; > + host->ops = &dsi_host_ops; > + ret = mipi_dsi_host_register(host); > + if (ret) { > + DRM_ERROR("failed to register dsi host\n"); > + return ret; > + } > + > + return 0; > +} > + > +static int dsi_parse_dt(struct platform_device *pdev, struct dw_dsi *dsi) > +{ > + struct dsi_hw_ctx *ctx = dsi->ctx; > + struct resource *res; > + > ctx->pclk = devm_clk_get(&pdev->dev, "pclk"); > if (IS_ERR(ctx->pclk)) { > DRM_ERROR("failed to get pclk clock\n"); > @@ -862,15 +859,19 @@ static int dsi_probe(struct platform_device *pdev) > } > dsi = &data->dsi; > ctx = &data->ctx; > + dsi->dev = &pdev->dev; > dsi->ctx = ctx; > > ret = dsi_parse_dt(pdev, dsi); > if (ret) > return ret; > > - platform_set_drvdata(pdev, data); > + ret = dsi_host_init(&pdev->dev, dsi); > + if (ret) > + return ret; > > - return component_add(&pdev->dev, &dsi_ops); > + platform_set_drvdata(pdev, data); > + return 0; > } > > static int dsi_remove(struct platform_device *pdev) > -- > 2.17.1 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
On 30.08.2019 19:00, Rob Clark wrote: > On Thu, Aug 29, 2019 at 11:52 PM Andrzej Hajda <a.hajda@samsung.com> wrote: >> On 29.08.2019 19:39, Rob Clark wrote: >>> On Wed, Aug 28, 2019 at 11:06 PM John Stultz <john.stultz@linaro.org> wrote: >>>> Since commit 83f35bc3a852 ("drm/bridge: adv7511: Attach to DSI >>>> host at probe time") landed in -next the HiKey board would fail >>>> to boot, looping: >>> No, please revert 83f35bc3a852.. that is going in the *complete* wrong >>> direction. We actually should be moving panels to not require dsi >>> host until attach time, similar to how bridges work, not the other way >>> around. >> >> Devices of panels and bridges controlled via DSI will not appear at all >> if DSI host is not created. >> >> So this is the only direction!!! >> > I disagree, there is really no harm in the bridge probing if there is no dsi. > > Furthermore, it seems that this change broke a few other drivers. If the bridge/panel is controlled via dsi, it will not be probed at all if DSI host/bus is not created, so it will not work at all. Upstream device will wait forever for downstream drm_(panel|bridge). So IMO we just do not have choice here. If you know better alternative let us know, otherwise we should proceed with "drm: kirin: Fix dsi probe/attach logic" patch. > >>> The problem is that, when dealing with bootloader enabled display, we >>> need to be really careful not to touch the hardware until the display >>> driver knows the bridge/panel is present. If the bridge/panel probes >>> after the display driver, we could end up killing scanout >>> (efifb/simplefb).. if the bridge/panel is missing some dependency and >>> never probes, it is rather unpleasant to be stuck trying to debug what >>> went wrong with no display. >> >> It has nothing to do with touching hardware, you can always (I hope) >> postpone it till all components are present. > Unfortunately this is harder than it sounds, since we need to read hw > revision registers for display and dsi blocks to know which hw > revision we are dealing with. > > (Also, we need to avoid > drm_fb_helper_remove_conflicting_framebuffers() until we know we are > ready to go.) > > We could possibly put more information in dt. But the less we depend > on dt, the easier time we'll have adding support for ACPI boot on the > windows arm laptops. > >> But it is just requirement of device/driver model in Linux Kernel. > yes and no.. the way the existing bridges work with a bridge->attach() > step seems fairly pragmatic to me. > >>> Sorry I didn't notice that adv7511 patch before it landed, but the >>> right thing to do now is to revert it. >> >> The 1st version of the patch was posted at the end of April and final >> version was queued 1st July, so it was quite long time for discussions >> and tests. > sorry I didn't notice the patch sooner, most of my bandwidth goes to mesa. > >> Reverting it now seems quite late, especially if the patch does right >> thing and there is already proper fix for one encoder (kirin), moreover >> revert will break another platforms. > kirin isn't the only other user of adv75xx.. at least it is my > understanding that this broke db410c as well. > >> Of course it seems you have different opinion what is the right thing in >> this case, so if you convince us that your approach is better one can >> revert the patch. > I guess my strongest / most immediate opinion is to not break other > existing adv75xx bridge users. It is pity that breakage happened, and next time we should be more strict about testing other platforms, before patch acceptance. But reverting it now will break also platform which depend on it. Anyway the old order was incorrect and prevented other users from adv* driver usage, so it should be fixed anyway. > Beyond that, I found doing mipi_dsi_attach() in bridge->attach() was > quite convenient to get display handover from efifb work. And that > was (previously) the way most of the bridges worked. > > But maybe there is another way.. perhaps somehow the bridges/panels > could be added as sub-components using the component framework, to > prevent the toplevel drm device from probing until they are ready? If you mean 'probe' as in initialization from component_master::bind callback with this patch it still works, DSI-HOST calls component_add after drm_bridge is found. > We'd still have the problem that the dsi component wants to be able to > read hw revision before registering dsi host.. but I suppose if CCF > exported a way that we could query whether the interface clk was > already enabled, we could have the clk enable/disable cycle that would > break efifb. I am not familiar with efifb, if you describe the issue you have in more detail we can try to find some solution together. Regards Andrzej > > BR, > -R > >
On Mon, Sep 2, 2019 at 6:22 AM Andrzej Hajda <a.hajda@samsung.com> wrote: > > On 30.08.2019 19:00, Rob Clark wrote: > > On Thu, Aug 29, 2019 at 11:52 PM Andrzej Hajda <a.hajda@samsung.com> wrote: > >> On 29.08.2019 19:39, Rob Clark wrote: > >>> On Wed, Aug 28, 2019 at 11:06 PM John Stultz <john.stultz@linaro.org> wrote: > >>>> Since commit 83f35bc3a852 ("drm/bridge: adv7511: Attach to DSI > >>>> host at probe time") landed in -next the HiKey board would fail > >>>> to boot, looping: > >>> No, please revert 83f35bc3a852.. that is going in the *complete* wrong > >>> direction. We actually should be moving panels to not require dsi > >>> host until attach time, similar to how bridges work, not the other way > >>> around. > >> > >> Devices of panels and bridges controlled via DSI will not appear at all > >> if DSI host is not created. > >> > >> So this is the only direction!!! > >> > > I disagree, there is really no harm in the bridge probing if there is no dsi. > > > > Furthermore, it seems that this change broke a few other drivers. > > > If the bridge/panel is controlled via dsi, it will not be probed at all > if DSI host/bus is not created, so it will not work at all. Upstream > device will wait forever for downstream drm_(panel|bridge). > > So IMO we just do not have choice here. > > If you know better alternative let us know, otherwise we should proceed > with "drm: kirin: Fix dsi probe/attach logic" patch. > > > > > >>> The problem is that, when dealing with bootloader enabled display, we > >>> need to be really careful not to touch the hardware until the display > >>> driver knows the bridge/panel is present. If the bridge/panel probes > >>> after the display driver, we could end up killing scanout > >>> (efifb/simplefb).. if the bridge/panel is missing some dependency and > >>> never probes, it is rather unpleasant to be stuck trying to debug what > >>> went wrong with no display. > >> > >> It has nothing to do with touching hardware, you can always (I hope) > >> postpone it till all components are present. > > Unfortunately this is harder than it sounds, since we need to read hw > > revision registers for display and dsi blocks to know which hw > > revision we are dealing with. > > > > (Also, we need to avoid > > drm_fb_helper_remove_conflicting_framebuffers() until we know we are > > ready to go.) > > > > We could possibly put more information in dt. But the less we depend > > on dt, the easier time we'll have adding support for ACPI boot on the > > windows arm laptops. > > > >> But it is just requirement of device/driver model in Linux Kernel. > > yes and no.. the way the existing bridges work with a bridge->attach() > > step seems fairly pragmatic to me. > > > >>> Sorry I didn't notice that adv7511 patch before it landed, but the > >>> right thing to do now is to revert it. > >> > >> The 1st version of the patch was posted at the end of April and final > >> version was queued 1st July, so it was quite long time for discussions > >> and tests. > > sorry I didn't notice the patch sooner, most of my bandwidth goes to mesa. > > > >> Reverting it now seems quite late, especially if the patch does right > >> thing and there is already proper fix for one encoder (kirin), moreover > >> revert will break another platforms. > > kirin isn't the only other user of adv75xx.. at least it is my > > understanding that this broke db410c as well. > > > >> Of course it seems you have different opinion what is the right thing in > >> this case, so if you convince us that your approach is better one can > >> revert the patch. > > I guess my strongest / most immediate opinion is to not break other > > existing adv75xx bridge users. > > > It is pity that breakage happened, and next time we should be more > strict about testing other platforms, before patch acceptance. > > But reverting it now will break also platform which depend on it. > > Anyway the old order was incorrect and prevented other users from adv* > driver usage, so it should be fixed anyway. > > > > Beyond that, I found doing mipi_dsi_attach() in bridge->attach() was > > quite convenient to get display handover from efifb work. And that > > was (previously) the way most of the bridges worked. > > > > But maybe there is another way.. perhaps somehow the bridges/panels > > could be added as sub-components using the component framework, to > > prevent the toplevel drm device from probing until they are ready? > > > If you mean 'probe' as in initialization from component_master::bind > callback with this patch it still works, DSI-HOST calls component_add > after drm_bridge is found. > > > > We'd still have the problem that the dsi component wants to be able to > > read hw revision before registering dsi host.. but I suppose if CCF > > exported a way that we could query whether the interface clk was > > already enabled, we could have the clk enable/disable cycle that would > > break efifb. > > > I am not familiar with efifb, if you describe the issue you have in more > detail we can try to find some solution together. > You don't really need to know too much about efifb.. the story would be the same with simplefb, the only difference is that the scanout address/size/format come from EFI GOP instead of dt. The main thing is we really want to avoid a runpm resume/suspend cycle until the we have all the components of the display, including bridge/panel. If the display is enabled by bootloader, then the initial resume will be no-op (turning on clks and power domains that are already on), but the following suspend will actually turn things off. If this happens because, for example, the bridge driver didn't get copied to initrd, or probe-deferred because it is missing one of it's dependencies, the result will be a black screen with no way to debug what went wrong. I guess if we can rely on panel/bridge being probed indirectly from mipi_dsi_host_register() (but before it returns, so dsi host can defer if bridge/panel is missing) maybe that works out.. BR, -R
On Mon, Sep 2, 2019 at 6:22 AM Andrzej Hajda <a.hajda@samsung.com> wrote: > On 30.08.2019 19:00, Rob Clark wrote: > > On Thu, Aug 29, 2019 at 11:52 PM Andrzej Hajda <a.hajda@samsung.com> wrote: > >> Of course it seems you have different opinion what is the right thing in > >> this case, so if you convince us that your approach is better one can > >> revert the patch. > > I guess my strongest / most immediate opinion is to not break other > > existing adv75xx bridge users. > > > It is pity that breakage happened, and next time we should be more > strict about testing other platforms, before patch acceptance. > > But reverting it now will break also platform which depend on it. I'm really of no opinion of which approach is better here, but I will say that when a patch breaks previously working boards, that's a regression and justifying that some other board is now enabled that would be broken by the revert (of a patch that is not yet upstream) isn't really a strong argument. I'm happy to work with folks to try to fixup the kirin driver if this patch really is the right approach, but we need someone to do the same for the db410c, and I don't think its fair to just dump that work onto folks under the threat of the board breaking. thanks -john
On 03.09.2019 18:18, John Stultz wrote: > On Mon, Sep 2, 2019 at 6:22 AM Andrzej Hajda <a.hajda@samsung.com> wrote: >> On 30.08.2019 19:00, Rob Clark wrote: >>> On Thu, Aug 29, 2019 at 11:52 PM Andrzej Hajda <a.hajda@samsung.com> wrote: >>>> Of course it seems you have different opinion what is the right thing in >>>> this case, so if you convince us that your approach is better one can >>>> revert the patch. >>> I guess my strongest / most immediate opinion is to not break other >>> existing adv75xx bridge users. >> >> It is pity that breakage happened, and next time we should be more >> strict about testing other platforms, before patch acceptance. >> >> But reverting it now will break also platform which depend on it. > I'm really of no opinion of which approach is better here, but I will > say that when a patch breaks previously working boards, that's a > regression and justifying that some other board is now enabled that > would be broken by the revert (of a patch that is not yet upstream) > isn't really a strong argument. > > I'm happy to work with folks to try to fixup the kirin driver if this > patch really is the right approach, but we need someone to do the same > for the db410c, and I don't think its fair to just dump that work onto > folks under the threat of the board breaking. These drivers should be fixed anyway - assumption that drm_bridge/drm_panel will be registered before the bus it is attached to is just incorrect. So instead of reverting, fixing and then re-applying the patch I have gently proposed shorter path. If you prefer long path we can try to go this way. Matt, is the pure revert OK for you or is it possible to prepare some workaround allowing cooperation with both approaches? Regards Andrzej > > thanks > -john > >
On Wed, Sep 4, 2019 at 3:26 AM Andrzej Hajda <a.hajda@samsung.com> wrote: > On 03.09.2019 18:18, John Stultz wrote: > > On Mon, Sep 2, 2019 at 6:22 AM Andrzej Hajda <a.hajda@samsung.com> wrote: > >> On 30.08.2019 19:00, Rob Clark wrote: > >>> On Thu, Aug 29, 2019 at 11:52 PM Andrzej Hajda <a.hajda@samsung.com> wrote: > >>>> Of course it seems you have different opinion what is the right thing in > >>>> this case, so if you convince us that your approach is better one can > >>>> revert the patch. > >>> I guess my strongest / most immediate opinion is to not break other > >>> existing adv75xx bridge users. > >> > >> It is pity that breakage happened, and next time we should be more > >> strict about testing other platforms, before patch acceptance. > >> > >> But reverting it now will break also platform which depend on it. > > I'm really of no opinion of which approach is better here, but I will > > say that when a patch breaks previously working boards, that's a > > regression and justifying that some other board is now enabled that > > would be broken by the revert (of a patch that is not yet upstream) > > isn't really a strong argument. > > > > I'm happy to work with folks to try to fixup the kirin driver if this > > patch really is the right approach, but we need someone to do the same > > for the db410c, and I don't think its fair to just dump that work onto > > folks under the threat of the board breaking. > > > These drivers should be fixed anyway - assumption that > drm_bridge/drm_panel will be registered before the bus it is attached to > is just incorrect. > > So instead of reverting, fixing and then re-applying the patch I have > gently proposed shorter path. If you prefer long path we can try to go > this way. > > Matt, is the pure revert OK for you or is it possible to prepare some > workaround allowing cooperation with both approaches? Rob/Andrzej: What's the call here? Should I resubmit the kirin fix for the adv7511 regression here? Or do we revert the adv7511 patch? I believe db410c still needs a fix. I'd just like to keep the HiKey board from breaking, so let me know so I can get the fix submitted if needed. thanks -john
diff --git a/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c b/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c index 5bf8138941de..696cee1a1219 100644 --- a/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c +++ b/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c @@ -79,6 +79,7 @@ struct dsi_hw_ctx { }; struct dw_dsi { + struct device *dev; struct drm_encoder encoder; struct drm_bridge *bridge; struct mipi_dsi_host host; @@ -724,51 +725,6 @@ static int dw_drm_encoder_init(struct device *dev, return 0; } -static int dsi_host_attach(struct mipi_dsi_host *host, - struct mipi_dsi_device *mdsi) -{ - struct dw_dsi *dsi = host_to_dsi(host); - - if (mdsi->lanes < 1 || mdsi->lanes > 4) { - DRM_ERROR("dsi device params invalid\n"); - return -EINVAL; - } - - dsi->lanes = mdsi->lanes; - dsi->format = mdsi->format; - dsi->mode_flags = mdsi->mode_flags; - - return 0; -} - -static int dsi_host_detach(struct mipi_dsi_host *host, - struct mipi_dsi_device *mdsi) -{ - /* do nothing */ - return 0; -} - -static const struct mipi_dsi_host_ops dsi_host_ops = { - .attach = dsi_host_attach, - .detach = dsi_host_detach, -}; - -static int dsi_host_init(struct device *dev, struct dw_dsi *dsi) -{ - struct mipi_dsi_host *host = &dsi->host; - int ret; - - host->dev = dev; - host->ops = &dsi_host_ops; - ret = mipi_dsi_host_register(host); - if (ret) { - DRM_ERROR("failed to register dsi host\n"); - return ret; - } - - return 0; -} - static int dsi_bridge_init(struct drm_device *dev, struct dw_dsi *dsi) { struct drm_encoder *encoder = &dsi->encoder; @@ -796,10 +752,6 @@ static int dsi_bind(struct device *dev, struct device *master, void *data) if (ret) return ret; - ret = dsi_host_init(dev, dsi); - if (ret) - return ret; - ret = dsi_bridge_init(drm_dev, dsi); if (ret) return ret; @@ -817,13 +769,22 @@ static const struct component_ops dsi_ops = { .unbind = dsi_unbind, }; -static int dsi_parse_dt(struct platform_device *pdev, struct dw_dsi *dsi) +static int dsi_host_attach(struct mipi_dsi_host *host, + struct mipi_dsi_device *mdsi) { - struct dsi_hw_ctx *ctx = dsi->ctx; - struct device_node *np = pdev->dev.of_node; - struct resource *res; + struct dw_dsi *dsi = host_to_dsi(host); + struct device_node *np = dsi->dev->of_node; int ret; + if (mdsi->lanes < 1 || mdsi->lanes > 4) { + DRM_ERROR("dsi device params invalid\n"); + return -EINVAL; + } + + dsi->lanes = mdsi->lanes; + dsi->format = mdsi->format; + dsi->mode_flags = mdsi->mode_flags; + /* * Get the endpoint node. In our case, dsi has one output port1 * to which the external HDMI bridge is connected. @@ -832,6 +793,42 @@ static int dsi_parse_dt(struct platform_device *pdev, struct dw_dsi *dsi) if (ret) return ret; + return component_add(dsi->dev, &dsi_ops); +} + +static int dsi_host_detach(struct mipi_dsi_host *host, + struct mipi_dsi_device *mdsi) +{ + /* do nothing */ + return 0; +} + +static const struct mipi_dsi_host_ops dsi_host_ops = { + .attach = dsi_host_attach, + .detach = dsi_host_detach, +}; + +static int dsi_host_init(struct device *dev, struct dw_dsi *dsi) +{ + struct mipi_dsi_host *host = &dsi->host; + int ret; + + host->dev = dev; + host->ops = &dsi_host_ops; + ret = mipi_dsi_host_register(host); + if (ret) { + DRM_ERROR("failed to register dsi host\n"); + return ret; + } + + return 0; +} + +static int dsi_parse_dt(struct platform_device *pdev, struct dw_dsi *dsi) +{ + struct dsi_hw_ctx *ctx = dsi->ctx; + struct resource *res; + ctx->pclk = devm_clk_get(&pdev->dev, "pclk"); if (IS_ERR(ctx->pclk)) { DRM_ERROR("failed to get pclk clock\n"); @@ -862,15 +859,19 @@ static int dsi_probe(struct platform_device *pdev) } dsi = &data->dsi; ctx = &data->ctx; + dsi->dev = &pdev->dev; dsi->ctx = ctx; ret = dsi_parse_dt(pdev, dsi); if (ret) return ret; - platform_set_drvdata(pdev, data); + ret = dsi_host_init(&pdev->dev, dsi); + if (ret) + return ret; - return component_add(&pdev->dev, &dsi_ops); + platform_set_drvdata(pdev, data); + return 0; } static int dsi_remove(struct platform_device *pdev)
Since commit 83f35bc3a852 ("drm/bridge: adv7511: Attach to DSI host at probe time") landed in -next the HiKey board would fail to boot, looping: adv7511 2-0039: failed to find dsi host messages over and over. Andrzej Hajda suggested this is due to a circular dependency issue, and that the adv7511 change is correcting the improper order used earlier. Unfortunately this means the DSI drivers that use adv7511 need to also need to be updated to use the proper ordering to continue to work. This patch tries to reorder the initialization to register the dsi_host first, and then call component_add via dsi_host_attach, instead of doing that at probe time. This seems to resolve the issue with the HiKey board. Cc: Andrzej Hajda <a.hajda@samsung.com> Cc: Matt Redfearn <matt.redfearn@thinci.com> Cc: Xinliang Liu <z.liuxinliang@hisilicon.com> Cc: Rongrong Zou <zourongrong@gmail.com> Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com> Cc: Neil Armstrong <narmstrong@baylibre.com> Cc: Jonas Karlman <jonas@kwiboo.se> Cc: Jernej Skrabec <jernej.skrabec@siol.net> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: David Airlie <airlied@linux.ie>, Cc: Sean Paul <seanpaul@chromium.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: "dri-devel@lists.freedesktop.org" <dri-devel@lists.freedesktop.org> Fixes: 83f35bc3a852 ("drm/bridge: adv7511: Attach to DSI host at probe time") Signed-off-by: John Stultz <john.stultz@linaro.org> --- Note: I'm really not super familiar with the DSI code here, and am mostly just trying to refactor the existing code in a similar fashion to the suggested dw-mipi-dsi-rockchip.c implementation. Careful review would be greatly appreciated! Also there is an outstanding regression on the db410c since it similarly uses the adv7511 and probably needs a similar rework. --- drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c | 111 ++++++++++--------- 1 file changed, 56 insertions(+), 55 deletions(-) -- 2.17.1