On 31.07.2015 17:58, Robert Baldyga wrote: > Hello, > > This patch set fixes bug causing serial hang in DMA mode for FIFO sizes > smaller than cache alignment. The first patch fixes DMA mode entering > condition to avoid starting with buffer smaller than cache line size. > Second patch fixes the serial hang bug, which was caused by unproper > buffer aligning algorithm which assumed that there is always enough > free space in FIFO for excessive bytes of buffer that is being alligned. > > Best regards, > Robert Baldyga > > Changelog: > > v2: > - Add CC to stable > - Add Reported-by: Krzysztof Kozlowski > - Change title of the first patch to more relevant > > v1: http://permalink.gmane.org/gmane.linux.kernel/2008281 > > Marek Szyprowski (1): > serial: samsung: fix DMA mode enter condition for small FIFO sizes > > Robert Baldyga (1): > serial: samsung: fix DMA for FIFO smaller than cache line size > > drivers/tty/serial/samsung.c | 47 +++++++++++++++++++++++++++++--------------- > drivers/tty/serial/samsung.h | 1 + > 2 files changed, 32 insertions(+), 16 deletions(-) > Tested on Trats2 (Exynos4412 with pl330, serial output on ttySAC2). Patchset fixes the reported issue (hang after applying "ARM: dts: exynos4: add DMA support for serial ports" [0]). However with [0] dmatest cannot execute tests on dma0 channels. Just silently passes but does not execute memcpy on any of dma0 channels. I wonder why... the serial ports use only some of dma0 channels, not all of them. Any ideas? [0] http://www.spinics.net/lists/linux-samsung-soc/msg45700.html Best regards, Krzysztof -- 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
