On Wed, Mar 27, 2013 at 05:21:13PM +0100, Michael Grzeschik wrote: > The udc uses an shared dma memory space between hard and software. This > memory layout is described in ci13xxx_qh and ci13xxx_td which are marked > with the attribute ((packed)). > > The compiler currently does not know about the alignment of the memory > layout, and will create strb and ldrb operations. > > The Datasheet of the synopsys core describes, that some operations on > the mapped memory need to be atomic double word operations. I.e. the > next pointer addressing in the qhead, as otherwise the hardware could > read wrong data and totally stuck. > > This patch adds the attribute ((aligned(4))) to the structures to tell > the compiler to use 32bit operations. It also adds an wmb() for the > prepared TD data before it gets enqueued into the qhead. > > Cc: stable <stable@xxxxxxxxxxxxxxx> How does this (and the other patches in this series) meet the stable_kernel_rules.txt requirements? greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
