Re: [PATCH v2] mtd: nand: pxa3xx-nand: prevent DFI bus lockup on removal

From: Robert Jarzmik
Date: Mon Sep 28 2015 - 03:55:15 EST

Brian Norris <computersforpeace@xxxxxxxxx> writes:

> On Sat, Sep 26, 2015 at 10:19:07PM +0200, Robert Jarzmik wrote:
>> Robert Jarzmik <robert.jarzmik@xxxxxxx> writes:
>> > After the conversion of pxa architecture to common clock framework, the
>> > NAND clock can be disabled on driver exit.
>> >
>> > In this case, it happens that if the driver used the NAND and set the
>> > DFI arbitration bit, the next access to a static memory controller area,
>> > such as an ethernet card, will stall the system bus, and the core will
>> > be stalled forever.
>> >
>> > This is especially true on pxa31x SoCs, where the NDCR was augmented
>> > with a new bit to prevent this lockups by giving full ownership of the
>> > DFI arbiter to the SMC, in change SCr#6.
>> >
>> > Fix this by clearing the DFI arbritration bit in driver exit. This
>> > effectively prevents a lockup on zylonite when removing pxa3xx-nand
>> > module, and using ethernet afterwards.
>> >
>> > Signed-off-by: Robert Jarzmik <robert.jarzmik@xxxxxxx>
>> Hi Brian,
>> Are you happy with this patch, and if so could you queue it please ?
> It looks OK to me, but it doesn't apply to the latest l2-mtd.git. Am I
> missing something? I didn't try too hard to work out the conflict
> myself.
OK, I'll rebase it on your tree and resend a "PATCH v2 REBASED" version today.


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at