| Message ID | 1357722258.2538.2.camel@pizza.hi.pengutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Dear Philipp Zabel, > Hi Marek, > > Am Dienstag, den 08.01.2013, 18:29 +0100 schrieb Marek Vasut: > > Dear Philipp Zabel, > > > > > Am Dienstag, den 08.01.2013, 18:09 +0100 schrieb Marek Vasut: > > > > Dear Fabio Estevam, > > > > > > > > > On Tue, Jan 8, 2013 at 2:41 PM, Fabio Estevam <festevam@gmail.com> wrote: > > > > > > Hi Sascha, > > > > > > > > > > > > On Mon, Nov 12, 2012 at 1:23 PM, Sascha Hauer > > > > > > <s.hauer@pengutronix.de> > > > > > > > > wrote: > > > > > >> The babbage board has a DVI-I output which allows to output > > > > > >> analog and digital signals simultaneously. This patch adds > > > > > >> support for it to the devicetree. The DDC signals are not wired > > > > > >> up on the board, so DRM will fall back on default VESA modes. > > > > > >> > > > > > >> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> > > > > > > > > > > > > I am running linux-next 20130108, which has this patch applied > > > > > > and I > > > > > > > > > > > get the following on my mx51babbage: > > > > > Ok, good news. I see a nice penguin on my monitor now. > > > > > > > > > > Discussed with Marek and he proposed a quick workaround: > > > > > > > > > > --- a/drivers/staging/imx-drm/ipuv3-crtc.c > > > > > +++ b/drivers/staging/imx-drm/ipuv3-crtc.c > > > > > @@ -343,6 +343,11 @@ static irqreturn_t ipu_irq_handler(int irq, > > > > > void *dev_id) { > > > > > > > > > > struct ipu_crtc *ipu_crtc = dev_id; > > > > > > > > > > + if (!ipu_crtc->imx_crtc) { > > > > > + pr_err("Spurious IPU IRQ\n"); > > > > > + return IRQ_HANDLED; > > > > > + } > > > > > + > > > > > > > > > > imx_drm_handle_vblank(ipu_crtc->imx_crtc); > > > > > > > > > > if (ipu_crtc->newfb) { > > > > > > > > > > It seems that this issue happened because bootloader leaves the IPU > > > > > turned on. > > > > > > > > To elaborate more on this stuff: > > > > > > > > 491 ipu_crtc->irq = ipu_idmac_channel_irq(ipu, > > > > ipu_crtc->ipu_ch, 492 IPU_IRQ_EOF); > > > > 493 ret = devm_request_irq(ipu_crtc->dev, ipu_crtc->irq, > > > > ipu_irq_handler, 0, > > > > 494 "imx_drm", ipu_crtc); > > > > 495 if (ret < 0) { > > > > 496 dev_err(ipu_crtc->dev, "irq request failed with > > > > %d.\n", ret); > > > > 497 goto err_out; > > > > 498 } > > > > 499 > > > > 500 disable_irq(ipu_crtc->irq); > > > > > > > > This code in drivers/staging/imx-drm/ipuv3-crtc.c is broken. If the > > > > IPU is on, it produces an interrupt before the driver is fully set > > > > up. I didn't produce a patch yet, I think I might offload this to > > > > someone else. Volunteers? > > > > > > Reordering the ipu_get_resources and imx_drm_add_crtc calls should > > > resolve this: > > > > > > From: Philipp Zabel <p.zabel@pengutronix.de> > > > Subject: [PATCH] staging: imx/drm: add crtc before registering > > > interrupt > > > > > > handler > > > > > > If the bootloader already enabled the display, the interrupt handler > > > will be called as soon as it is registered. If the CRTC is not already > > > added at this time, the call to imx_drm_handle_vblank will result in > > > a NULL pointer dereference. > > > > I ain't no IPU expert, but isn't adding the component before having it > > fully inited even worse? > > Good point, how about just moving the irq request out of > ipu_get_resources into ipu_crtc_init, after adding the crtc: > > From: Philipp Zabel <p.zabel@pengutronix.de> > Subject: [PATCH] staging: imx/drm: request irq only after adding the crtc > > If the bootloader already enabled the display, the interrupt handler > will be called as soon as it is registered. If the CRTC is not already > added at this time, the call to imx_drm_handle_vblank will result in > a NULL pointer dereference. Can we not just flush (and make sure it's disabled) the IRQ before requesting it ? That'd be probably the most sane way
Am Mittwoch, den 09.01.2013, 10:26 +0100 schrieb Marek Vasut: > Dear Philipp Zabel, > > > Hi Marek, > > > > Am Dienstag, den 08.01.2013, 18:29 +0100 schrieb Marek Vasut: > > > Dear Philipp Zabel, > > > > > > > Am Dienstag, den 08.01.2013, 18:09 +0100 schrieb Marek Vasut: > > > > > Dear Fabio Estevam, > > > > > > > > > > > On Tue, Jan 8, 2013 at 2:41 PM, Fabio Estevam <festevam@gmail.com> > wrote: > > > > > > > Hi Sascha, > > > > > > > > > > > > > > On Mon, Nov 12, 2012 at 1:23 PM, Sascha Hauer > > > > > > > <s.hauer@pengutronix.de> > > > > > > > > > > wrote: > > > > > > >> The babbage board has a DVI-I output which allows to output > > > > > > >> analog and digital signals simultaneously. This patch adds > > > > > > >> support for it to the devicetree. The DDC signals are not wired > > > > > > >> up on the board, so DRM will fall back on default VESA modes. > > > > > > >> > > > > > > >> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> > > > > > > > > > > > > > > I am running linux-next 20130108, which has this patch applied > > > > > > > and I > > > > > > > > > > > > > get the following on my mx51babbage: > > > > > > Ok, good news. I see a nice penguin on my monitor now. > > > > > > > > > > > > Discussed with Marek and he proposed a quick workaround: > > > > > > > > > > > > --- a/drivers/staging/imx-drm/ipuv3-crtc.c > > > > > > +++ b/drivers/staging/imx-drm/ipuv3-crtc.c > > > > > > @@ -343,6 +343,11 @@ static irqreturn_t ipu_irq_handler(int irq, > > > > > > void *dev_id) { > > > > > > > > > > > > struct ipu_crtc *ipu_crtc = dev_id; > > > > > > > > > > > > + if (!ipu_crtc->imx_crtc) { > > > > > > + pr_err("Spurious IPU IRQ\n"); > > > > > > + return IRQ_HANDLED; > > > > > > + } > > > > > > + > > > > > > > > > > > > imx_drm_handle_vblank(ipu_crtc->imx_crtc); > > > > > > > > > > > > if (ipu_crtc->newfb) { > > > > > > > > > > > > It seems that this issue happened because bootloader leaves the IPU > > > > > > turned on. > > > > > > > > > > To elaborate more on this stuff: > > > > > > > > > > 491 ipu_crtc->irq = ipu_idmac_channel_irq(ipu, > > > > > ipu_crtc->ipu_ch, 492 IPU_IRQ_EOF); > > > > > 493 ret = devm_request_irq(ipu_crtc->dev, ipu_crtc->irq, > > > > > ipu_irq_handler, 0, > > > > > 494 "imx_drm", ipu_crtc); > > > > > 495 if (ret < 0) { > > > > > 496 dev_err(ipu_crtc->dev, "irq request failed with > > > > > %d.\n", ret); > > > > > 497 goto err_out; > > > > > 498 } > > > > > 499 > > > > > 500 disable_irq(ipu_crtc->irq); > > > > > > > > > > This code in drivers/staging/imx-drm/ipuv3-crtc.c is broken. If the > > > > > IPU is on, it produces an interrupt before the driver is fully set > > > > > up. I didn't produce a patch yet, I think I might offload this to > > > > > someone else. Volunteers? > > > > > > > > Reordering the ipu_get_resources and imx_drm_add_crtc calls should > > > > resolve this: > > > > > > > > From: Philipp Zabel <p.zabel@pengutronix.de> > > > > Subject: [PATCH] staging: imx/drm: add crtc before registering > > > > interrupt > > > > > > > > handler > > > > > > > > If the bootloader already enabled the display, the interrupt handler > > > > will be called as soon as it is registered. If the CRTC is not already > > > > added at this time, the call to imx_drm_handle_vblank will result in > > > > a NULL pointer dereference. > > > > > > I ain't no IPU expert, but isn't adding the component before having it > > > fully inited even worse? > > > > Good point, how about just moving the irq request out of > > ipu_get_resources into ipu_crtc_init, after adding the crtc: > > > > From: Philipp Zabel <p.zabel@pengutronix.de> > > Subject: [PATCH] staging: imx/drm: request irq only after adding the crtc > > > > If the bootloader already enabled the display, the interrupt handler > > will be called as soon as it is registered. If the CRTC is not already > > added at this time, the call to imx_drm_handle_vblank will result in > > a NULL pointer dereference. > > Can we not just flush (and make sure it's disabled) the IRQ before requesting it > ? That'd be probably the most sane way Probably, but that still would be no excuse for the interrupt handler to be registered before it can actually handle interrupts. regards Philipp
Dear Philipp Zabel, > Am Mittwoch, den 09.01.2013, 10:26 +0100 schrieb Marek Vasut: > > Dear Philipp Zabel, > > > > > Hi Marek, > > > > > > Am Dienstag, den 08.01.2013, 18:29 +0100 schrieb Marek Vasut: > > > > Dear Philipp Zabel, > > > > > > > > > Am Dienstag, den 08.01.2013, 18:09 +0100 schrieb Marek Vasut: > > > > > > Dear Fabio Estevam, > > > > > > > > > > > > > On Tue, Jan 8, 2013 at 2:41 PM, Fabio Estevam > > > > > > > <festevam@gmail.com> > > > > wrote: > > > > > > > > Hi Sascha, > > > > > > > > > > > > > > > > On Mon, Nov 12, 2012 at 1:23 PM, Sascha Hauer > > > > > > > > <s.hauer@pengutronix.de> > > > > > > > > > > > > wrote: > > > > > > > >> The babbage board has a DVI-I output which allows to output > > > > > > > >> analog and digital signals simultaneously. This patch adds > > > > > > > >> support for it to the devicetree. The DDC signals are not > > > > > > > >> wired up on the board, so DRM will fall back on default > > > > > > > >> VESA modes. > > > > > > > >> > > > > > > > >> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> > > > > > > > > > > > > > > > > I am running linux-next 20130108, which has this patch > > > > > > > > applied and I > > > > > > > > > > > > > > > get the following on my mx51babbage: > > > > > > > Ok, good news. I see a nice penguin on my monitor now. > > > > > > > > > > > > > > Discussed with Marek and he proposed a quick workaround: > > > > > > > > > > > > > > --- a/drivers/staging/imx-drm/ipuv3-crtc.c > > > > > > > +++ b/drivers/staging/imx-drm/ipuv3-crtc.c > > > > > > > @@ -343,6 +343,11 @@ static irqreturn_t ipu_irq_handler(int > > > > > > > irq, void *dev_id) { > > > > > > > > > > > > > > struct ipu_crtc *ipu_crtc = dev_id; > > > > > > > > > > > > > > + if (!ipu_crtc->imx_crtc) { > > > > > > > + pr_err("Spurious IPU IRQ\n"); > > > > > > > + return IRQ_HANDLED; > > > > > > > + } > > > > > > > + > > > > > > > > > > > > > > imx_drm_handle_vblank(ipu_crtc->imx_crtc); > > > > > > > > > > > > > > if (ipu_crtc->newfb) { > > > > > > > > > > > > > > It seems that this issue happened because bootloader leaves the > > > > > > > IPU turned on. > > > > > > > > > > > > To elaborate more on this stuff: > > > > > > > > > > > > 491 ipu_crtc->irq = ipu_idmac_channel_irq(ipu, > > > > > > ipu_crtc->ipu_ch, 492 IPU_IRQ_EOF); > > > > > > 493 ret = devm_request_irq(ipu_crtc->dev, ipu_crtc->irq, > > > > > > ipu_irq_handler, 0, > > > > > > 494 "imx_drm", ipu_crtc); > > > > > > 495 if (ret < 0) { > > > > > > 496 dev_err(ipu_crtc->dev, "irq request failed > > > > > > with %d.\n", ret); > > > > > > 497 goto err_out; > > > > > > 498 } > > > > > > 499 > > > > > > 500 disable_irq(ipu_crtc->irq); > > > > > > > > > > > > This code in drivers/staging/imx-drm/ipuv3-crtc.c is broken. If > > > > > > the IPU is on, it produces an interrupt before the driver is > > > > > > fully set up. I didn't produce a patch yet, I think I might > > > > > > offload this to someone else. Volunteers? > > > > > > > > > > Reordering the ipu_get_resources and imx_drm_add_crtc calls should > > > > > resolve this: > > > > > > > > > > From: Philipp Zabel <p.zabel@pengutronix.de> > > > > > Subject: [PATCH] staging: imx/drm: add crtc before registering > > > > > interrupt > > > > > > > > > > handler > > > > > > > > > > If the bootloader already enabled the display, the interrupt > > > > > handler will be called as soon as it is registered. If the CRTC is > > > > > not already added at this time, the call to imx_drm_handle_vblank > > > > > will result in a NULL pointer dereference. > > > > > > > > I ain't no IPU expert, but isn't adding the component before having > > > > it fully inited even worse? > > > > > > Good point, how about just moving the irq request out of > > > ipu_get_resources into ipu_crtc_init, after adding the crtc: > > > > > > From: Philipp Zabel <p.zabel@pengutronix.de> > > > Subject: [PATCH] staging: imx/drm: request irq only after adding the > > > crtc > > > > > > If the bootloader already enabled the display, the interrupt handler > > > will be called as soon as it is registered. If the CRTC is not already > > > added at this time, the call to imx_drm_handle_vblank will result in > > > a NULL pointer dereference. > > > > Can we not just flush (and make sure it's disabled) the IRQ before > > requesting it ? That'd be probably the most sane way > > Probably, but that still would be no excuse for the interrupt handler to > be registered before it can actually handle interrupts. Yep, fully agreed. Ok, can you check if the IRQ can be somehow flushed/disabled and then apply your last patch (the one that pulls the IRQ registration past imx_drm_add_crtc() )? That'd sound to me like a reasonable solution, what do you say? Apparently imx_drm_add_crtc() doesn't use the IRQ, so it should be cool too.
diff --git a/drivers/staging/imx-drm/ipuv3-crtc.c b/drivers/staging/imx-drm/ipuv3-crtc.c index 4b3a019..b028b0d 100644 --- a/drivers/staging/imx-drm/ipuv3-crtc.c +++ b/drivers/staging/imx-drm/ipuv3-crtc.c @@ -483,17 +483,6 @@ static int ipu_get_resources(struct ipu_crtc *ipu_crtc, goto err_out; } - ipu_crtc->irq = ipu_idmac_channel_irq(ipu, ipu_crtc->ipu_ch, - IPU_IRQ_EOF); - ret = devm_request_irq(ipu_crtc->dev, ipu_crtc->irq, ipu_irq_handler, 0, - "imx_drm", ipu_crtc); - if (ret < 0) { - dev_err(ipu_crtc->dev, "irq request failed with %d.\n", ret); - goto err_out; - } - - disable_irq(ipu_crtc->irq); - return 0; err_out: ipu_put_resources(ipu_crtc); @@ -504,6 +493,7 @@ err_out: static int ipu_crtc_init(struct ipu_crtc *ipu_crtc, struct ipu_client_platformdata *pdata) { + struct ipu_soc *ipu = dev_get_drvdata(ipu_crtc->dev->parent); int ret; ret = ipu_get_resources(ipu_crtc, pdata); @@ -522,6 +512,17 @@ static int ipu_crtc_init(struct ipu_crtc *ipu_crtc, goto err_put_resources; } + ipu_crtc->irq = ipu_idmac_channel_irq(ipu, ipu_crtc->ipu_ch, + IPU_IRQ_EOF); + ret = devm_request_irq(ipu_crtc->dev, ipu_crtc->irq, ipu_irq_handler, 0, + "imx_drm", ipu_crtc); + if (ret < 0) { + dev_err(ipu_crtc->dev, "irq request failed with %d.\n", ret); + goto err_put_resources; + } + + disable_irq(ipu_crtc->irq); + return 0; err_put_resources: