On Friday 17 November 2006 00:12, Sylvain Munaut wrote: > * The manual states we should check for the TIP bit before all > PIO transaction. That's not really supported by libata and requires > reimplementing almost all the hooks. But after talking to Freescale, > it turnsout it's not really necessary. So this driver doesn't implement > that check. I noticed no problem so far ... I've had some bad experiences with 2.4 line kernel when using BAPI 2.2 on Rev. A 5200 while imposing heavy I/O load. Problems manifested as hanging XLB-bus and so on. Funny thing is that combinations like Rev.A + BAPI 2.1 and Rev.B + BAPI 2.[12] seem to be immune while doing similar stress tests. Problems went away after wrapping PIO access like this: 1. Stop XLB-pipelining 2. Wait for TIP bit to go down. 3. Do the access 4. Restore XLB-pipelining. Just polling for the TIP bit is not enough due to errata on Rev. A if the pipelining is enabled. Just in case if someone else is having mysterious hangs on Rev.A:s with newer microcode. :) - Jarno - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
