On Fri, 16 Jun 2023 at 22:42, Linus Walleij <linus.walleij@xxxxxxxxxx> wrote: > > This series start to fix a pretty serious problem in the MMCI > busy detect handling, discovered only after going up and > down a ladder of refactorings. > > The code is written expecting the Ux500 busy detect > to fire two interrupts: one at the start of the busy > signalling and one at the end of the busy signalling. > > DAT0 busy +-----------------+ > | | > DAT0 not busy ----+ +-------- > > ^ ^ > | | > IRQ1 IRQ2 > > The root cause of the problem seen on some devices > is that only the first IRQ arrives, and then the device > hangs, waiting perpetually for the next IRQ to arrive. > > Sometimes neither IRQ arrives! This could be because > the card is so fast that the MCLK does not have time > to latch out the IRQ signal to the bus before it is > gone. > > I included the rewrite of the entire busy detect logic > to use a state machine as this makes it way easier to > debug and will print messages about other error > conditions as well. > > The problem affects especially the Skomer > (Samsung GT-I9070) and Kyle (Samsung SGH-I407). > > This series does not finally solve the problem, but > prepares the ground by making it possible to solve. > I see no regressions on the HREF boards or the > known-good Golden device, but enabling the debug > prints reveals why we have problems on the Skomer: > > U8500 HREFv60 TVK: > > [ 2.343785] mmci-pl18x 80114000.mmc: mmc3: PL180 manf 80 rev4 at 0x80114000 irq 83,0 (pio) > [ 2.352789] mmci-pl18x 80114000.mmc: DMA channels RX dma0chan8, TX dma0chan9 > [ 2.609727] mmc3: new high speed MMC card at address 0001 > [ 2.610762] mmcblk3: mmc3:0001 008G03 7.38 GiB > [ 2.612989] mmcblk3: p1 > [ 2.613824] mmcblk3boot0: mmc3:0001 008G03 2.00 MiB > [ 2.615367] mmcblk3boot1: mmc3:0001 008G03 2.00 MiB > [ 2.616721] mmcblk3rpmb: mmc3:0001 008G03 128 KiB, chardev (246:1) > > Then I can mount partitions etc. > > U8500 HREF520P TVK: > > [ 3.064950] mmci-pl18x 80114000.mmc: mmc3: PL180 manf 80 rev4 at 0x80114000 irq 88,0 (pio) > [ 3.075458] mmci-pl18x 80114000.mmc: DMA channels RX dma0chan10, TX dma0chan11 > [ 3.558157] mmc3: new high speed MMC card at address 0001 > [ 3.573992] mmcblk3: mmc3:0001 SEM16G 14.8 GiB > [ 3.595782] mmcblk3boot0: mmc3:0001 SEM16G 2.00 MiB > [ 3.610788] mmcblk3boot1: mmc3:0001 SEM16G 2.00 MiB > [ 3.633313] mmcblk3rpmb: mmc3:0001 SEM16G 128 KiB, chardev (246:0) > > Golden: > > [ 2.993989] mmci-pl18x 80005000.mmc: mmc2: PL180 manf 80 rev4 at 0x80005000 irq 82,0 (pio) > [ 3.003348] mmci-pl18x 80005000.mmc: DMA channels RX dma0chan4, TX dma0chan5 > [ 3.134052] mmci-pl18x 80005000.mmc: no busy signalling in time > [ 3.142300] mmc2: new DDR MMC card at address 0001 > [ 3.148051] mmcblk2: mmc2:0001 SEM08G 7.28 GiB > [ 3.155668] mmc1: new high speed SDIO card at address 0001 > [ 3.167170] mmcblk2: p1 p2 p3 p4 p5 p6 p7 p8 p9 p10 p11 p12 p13 p14 p15 p16 p17 p18 p19 p20 p21 p22 p23 p24 p25 > [ 3.232390] mmcblk2boot0: mmc2:0001 SEM08G 2.00 MiB > [ 3.242865] mmcblk2boot1: mmc2:0001 SEM08G 2.00 MiB > [ 3.249808] mmcblk2rpmb: mmc2:0001 SEM08G 128 KiB, chardev (246:0) > > Notice an initial error message, then it stabilizes. > > Then I can mount partitions etc. > > Skomer: > > [ 2.659027] mmci-pl18x 80005000.mmc: mmc2: PL180 manf 80 rev4 at 0x80005000 irq 81,0 (pio) > [ 2.670135] mmci-pl18x 80005000.mmc: DMA channels RX dma0chan4, TX dma0chan5 > [ 3.380554] mmci-pl18x 80005000.mmc: no busy signalling in time > [ 3.387420] mmci-pl18x 80005000.mmc: no busy signalling in time > [ 3.394561] mmci-pl18x 80005000.mmc: lost busy status when waiting for busy start IRQ > [ 3.402893] mmci-pl18x 80005000.mmc: no busy signalling in time > [ 3.409088] mmc2: new DDR MMC card at address 0001 > [ 3.433166] mmcblk2: mmc2:0001 M4G1YC 3.69 GiB > [ 3.466766] mmcblk2: p1 p2 p3 p4 p5 p6 p7 p8 p9 p10 p11 p12 p13 p14 p15 p16 p17 p18 p19 p20 p21 p22 p23 p24 p25 > [ 3.485076] mmcblk2boot0: mmc2:0001 M4G1YC 2.00 MiB > [ 3.503265] mmcblk2boot1: mmc2:0001 M4G1YC 2.00 MiB > [ 3.524993] mmcblk2rpmb: mmc2:0001 M4G1YC 128 KiB, chardev (246:0) > [ 4.470245] mmci-pl18x 80005000.mmc: no busy signalling in time > [ 4.489227] mmci-pl18x 80005000.mmc: no busy signalling in time > [ 5.457244] mmci-pl18x 80005000.mmc: no busy signalling in time > [ 5.469512] mmci-pl18x 80005000.mmc: lost busy status when waiting for busy start IRQ > [ 7.133880] mmci-pl18x 80005000.mmc: no busy signalling in time > [ 7.154541] mmci-pl18x 80005000.mmc: no busy signalling in time > [ 7.189270] mmci-pl18x 80005000.mmc: no busy signalling in time > [ 7.542175] mmci-pl18x 80005000.mmc: no busy signalling in time > [ 7.552886] mmci-pl18x 80005000.mmc: no busy signalling in time > [ 8.277618] mmci-pl18x 80005000.mmc: timeout waiting for busy IRQ > > This is why the Skomer isn't working. > > Next up will be a patch or patches fixing the issue. > > Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx> Applied for next, thanks! [...] Kind regards Uffe
