Thanks, Vaibhav Hiremath > -----Original Message----- > From: linux-omap-owner@xxxxxxxxxxxxxxx [mailto:linux-omap- > owner@xxxxxxxxxxxxxxx] On Behalf Of Tomi Valkeinen > Sent: Monday, November 10, 2008 2:01 PM > To: rick@xxxxxxx > Cc: imre.deak@xxxxxxxxx; aam@xxxxxxxxxxxx; juha.yrjola@xxxxxxxxx; > dirk.behme@xxxxxxxxxxxx; linux-omap@xxxxxxxxxxxxxxx > Subject: Re: Fix for dispc's error "omapfb omapfb: irq error status > 4020" > > Hi, > > On Fri, 2008-11-07 at 12:55 -0800, ext Rick Bronson wrote: > > Folks, > > > > Please take a look at this change to drivers/video/omap/dispc.c. > It > > addresses a problem seen on some boots of OMAP's. On about 1 in > 30 > > boots one gets an endless stream of interrupts from the > > DISPC_IRQ_SYNC_LOST bit in the DISPC_IRQSTATUS register. The > > following messages are printed. > > > > omapfb omapfb: irq error status 4020 > > > > The correct solution to this problem is to perform a "soft > reset" > > but that requires a bit of re-architecturing of the code as the > init > > routine would have to be split up, etc. See the OMAP pdf, search > for > > "To clear a synchronization lost interrupt". > > > > This patch allows the above error message to get printed once > and > > then disables further DISPC_IRQ_SYNC_LOST interrups. > > > > Comments? > > I think the correct solution would be to find out why we get sync > lost > errors and fix that. Your patch just hides the problem. > > However, I agree that it's not good to just keep spamming the error, > possibly making the board freeze. The new DSS turns the display off > after 100 error messages. But I don't think just hiding the > interrupt is > a good change. > [Hiremath, Vaibhav] Yes, it is not a good practice to hide any interrupts. But I think even instead of turning of the DSS, you should reset the DSS and reconfigure it with default values or preserve the state before resetting and configure it again. I agree to the point that, it requires lot of re-architectureing to the current driver. But I believe it should be possible with new omap2 version. > > > > Thanks, > > > > Rick > > Tomi > > > > > > --- linux-omap-2.6/drivers/video/omap/dispc.c.~1~ 2008-11-04 > 14:23:38.000000000 -0800 > > +++ linux-omap-2.6/drivers/video/omap/dispc.c 2008-11-07 > 12:34:54.000000000 -0800 > > @@ -157,7 +157,7 @@ struct resmap { > > > > #define MAX_IRQ_HANDLERS 4 > > > > -static struct { > > +static struct omapfb_dispc { > > void __iomem *base; > > > > struct omapfb_mem_desc mem_desc; > > @@ -169,6 +169,7 @@ static struct { > > > > int ext_mode; > > > > + u32 irq_error_mask; /* mask used for errors */ > > struct { > > u32 irq_mask; > > void (*callback)(void *); > > @@ -812,16 +813,16 @@ static void set_lcd_timings(void) > > panel->pixel_clock = fck / lck_div / pck_div / 1000; > > } > > > > -static void recalc_irq_mask(void) > > +static void recalc_irq_mask(struct omapfb_dispc *p_dispc) > > { > > int i; > > - unsigned long irq_mask = DISPC_IRQ_MASK_ERROR; > > + unsigned long irq_mask = p_dispc->irq_error_mask; > > > > for (i = 0; i < MAX_IRQ_HANDLERS; i++) { > > - if (!dispc.irq_handlers[i].callback) > > + if (!p_dispc->irq_handlers[i].callback) > > continue; > > > > - irq_mask |= dispc.irq_handlers[i].irq_mask; > > + irq_mask |= p_dispc->irq_handlers[i].irq_mask; > > } > > > > enable_lcd_clocks(1); > > @@ -843,7 +844,7 @@ int omap_dispc_request_irq(unsigned long > > dispc.irq_handlers[i].irq_mask = irq_mask; > > dispc.irq_handlers[i].callback = callback; > > dispc.irq_handlers[i].data = data; > > - recalc_irq_mask(); > > + recalc_irq_mask(&dispc); > > > > return 0; > > } > > @@ -863,7 +864,7 @@ void omap_dispc_free_irq(unsigned long i > > dispc.irq_handlers[i].irq_mask = 0; > > dispc.irq_handlers[i].callback = NULL; > > dispc.irq_handlers[i].data = NULL; > > - recalc_irq_mask(); > > + recalc_irq_mask(&dispc); > > return; > > } > > } > > @@ -884,6 +885,10 @@ static irqreturn_t omap_dispc_irq_handle > > complete(&dispc.frame_done); > > > > if (stat & DISPC_IRQ_MASK_ERROR) { > > + if (stat & DISPC_IRQ_SYNC_LOST) { /* only allow sync > lost once or we end up... */ > > + dispc.irq_error_mask &= ~DISPC_IRQ_SYNC_LOST; /* > with a barrage of interrupts */ > > + recalc_irq_mask(&dispc); > > + } > > if (printk_ratelimit()) { > > dev_err(dispc.fbdev->dev, "irq error status > %04x\n", > > stat & 0x7fff); > > @@ -897,6 +902,7 @@ static irqreturn_t omap_dispc_irq_handle > > } > > > > dispc_write_reg(DISPC_IRQSTATUS, stat); > > + stat = dispc_read_reg(DISPC_IRQSTATUS); > > > > enable_lcd_clocks(0); > > > > @@ -1432,7 +1438,8 @@ static int omap_dispc_init(struct omapfb > > l = dispc_read_reg(DISPC_IRQSTATUS); > > dispc_write_reg(DISPC_IRQSTATUS, l); > > > > - recalc_irq_mask(); > > + dispc.irq_error_mask = DISPC_IRQ_MASK_ERROR; /* init error > mask */ > > + recalc_irq_mask(&dispc); > > > > if ((r = request_irq(INT_24XX_DSS_IRQ, omap_dispc_irq_handler, > > 0, MODULE_NAME, fbdev)) < 0) { > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux- > omap" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- > To unsubscribe from this list: send the line "unsubscribe linux- > omap" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
