28.10.2019 17:27, Peter De Schrijver пишет: > On Tue, Jul 23, 2019 at 05:52:44AM +0300, Dmitry Osipenko wrote: >> Unset "enable" bit means that divider is in bypass mode, hence it doesn't >> have any effect in that case. Please note that there are no known bugs >> caused by the missing check. >> > > Technically this is not quite true, but for the purposes of CCF you can > treat it that way. This bits defines if the value in the lower 16 bits > of the divider register is used to configure the divider or if the > contents of the UART DLM/DLL registers is used. So the divider isn't > actually bypassed, it's just configured differently. > In practice this bit is only set when the divider is non-zero when doing > set rate. So the extra test isn't strictly needed as long as the sw > running before the kernel also ensures the bit is only set when the > divider is non-zero. > > Acked-by: Peter De Schrijver <pdeschrijver@xxxxxxxxxx> Thank you for the clarification. I hope that bootloader doesn't enable the divider because it looks like standard 8250 driver won't be ready for that. But serial-tegra driver seems should be good.
