On Wed, Nov 21, 2018 at 12:51:28PM -0500, Prarit Bhargava wrote: > On 11/21/2018 08:43 AM, Andy Shevchenko wrote: > > Since SPCR 1.04 [1] the baud rate of 0 means a preconfigured state of UART. > > Assume firmware or bootloader configures console correctly. > > > > [1]: https://docs.microsoft.com/en-us/windows-hardware/drivers/serports/serial-port-console-redirection-table > > + if (!baud_rate) { > > snprintf(opts, sizeof(opts), "%s,%s,0x%llx", uart, iotype, > > table->serial_port.address); > > } else { > OOC what happens if you pass in opts="uart,io,0x3f8,0" to setup_earlycon() and > add_preferred_console() ? Nothing critical for 8250, though a) we have a plenty of UART drivers and I don't check them; b) the code above (avoidance of 0 to be baud rate parameter) is already in upstream by some reason (see a) as well). So, I wouldn't touch that logic. -- With Best Regards, Andy Shevchenko
