Hi On Wed, Apr 3, 2013 at 11:21 PM, Paul Walmsley <paul@xxxxxxxxx> wrote: > Hi, > > On Wed, 3 Apr 2013, Alexey Pelykh wrote: > >> But, since we've found the issue, I suggest that we should look at it >> closer, especially since at this moment only you can reproduce it. As >> far as I understand, but I may be wrong, >> this comment is wrong, since if to specify >> OMAP_UART_SCR_RX_TRIG_GRANU1_MASK, it effectively sets Rx threshold to >> 1 character, instead of 16. >> /* Set receive FIFO threshold to 16 characters and >> * transmit FIFO threshold to 16 spaces >> */ > > If you want to continue to experiment with it, I'd be willing to do an > occasional test boot on 37xx EVM. It's nice to see community patches... > I'm pretty sure that current configuration of UART indeed sets Rx FIFO threshold to 1 character, as opposite to 16 characters mentioned in comments. Kernel 3.3 is the origin of Rx 1-char-granularity bit setting, but states clearly that Rx FIFO is being set to 1 character in non-DMA mode. The comment appears between 3.6 and 3.7 in commit 6721ab7f77f2614ab43e3de2f908b1d7436331df by Felipe Balbi. 3.0-3.2 kernels don't have 1-char-granularity enabled, and Rx FIFO threshold level was effectively set to 16 characters, what should be the same as my patch that turned off 1-char-granularity Paul, can you confirm (if possible, surely) if 3.0-3.2 kernels had same issue? Felipe, it would be great to get your comments on this? > > - Paul -- 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
