On Thu, 25 Aug 2022, Ilpo Järvinen wrote: > In theory, the Tx code would be buggy if UART_XMIT_SIZE differs from > 4096 (occurs when PAGE_SIZE > 4k), however, given the lack of issue > reports such configuration likely doesn't occur with any real platform > with dz HW. The inconsisted sizes would cause missing characters and > never-ending bogus Tx when ->head reaches the region above 4k. The > issue, if it would be real, would predate git days. This is misleading. There are exactly 3 machine models (2 major ones and 1 extra submodel) that we currently support which make use of this serial port hardware and driver, and they all have their R2000/R3000 MIPS CPU soldered onto their respective mainboards. And the CPUs they use all have their page size hardwired to 4KiB, so it's not the lack of reports, but a firm assertion that this driver as it stands shall never be used with a different page size. There exists an option card using a DZ11-compatible chipset that can be used with systems we currently support with page sizes of up to 64KiB, but to the best of my knowledge only a number of prototype cards has been made and I have heard of exactly one person having such a card. Therefore we do not support it and may never do, so it is not a concern for the driver as it stands and shall not be mentioned. Please just state then that the change is for design consistency with the serial core and redefine DZ_XMIT_SIZE in terms of UART_XMIT_SIZE as I suggested for v1. I'll ack such a change. Please drop 2/2 at this stage as it does not fix any bug and does not appear to add any value to this driver. Thanks, Maciej
