On 05/20/2013 07:39 PM, Jongsung Kim wrote: > Jongsung Kim <neidhard.kim@xxxxxxx> : >> Stephen Warren <swarren@xxxxxxxxxxxxx> : >>>> All r1p5 have 32-byte FIFO depth and it's not configurable. From the >>>> PL011 >>>> TRM: >>>> >>>> r1p4-r1p5 Contains the following differences in functionality: >>>> * The receive and transmit FIFOs are increased to a depth of > 32. >>>> * The Revision field in the UARTPeriphID2 Register on page > 3-24 >>>> bits [7:4] now reads back as 0x3. >>> >>> Well, that certainly isn't true in practice. I think we should revert >>> this commit until we can determine what the problem is. >> >> I asked to the ARM support about this. Waiting for reply.. > > ARM support said they doesn't have information about BCM2835 UART. Does > anyone have a communication channel to Broadcom? It takes time for me to > get contact point to Broadcom.. (I'm trying) > > However, ARM support also said: > > "If the Broadcom part definitely has 16-deep FIFOs, it cannot be based > on a PL011 r1p5, so I might guess that Broadcom have just referenced > the latest version of the documentation on our website, but have actually > implemented an earlier version." This all seems rather academic. Irrespective of what the cause of the problem is, the commit actively breaks a previously working configuration. I still believe we should revert it first, then find out exactly what's going on later. Should I sent the revert commit? -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html