Hi Mark, On 12/03/2016 12:15 PM, Mark Salter wrote: > On Sat, 2016-12-03 at 05:06 -0500, Jon Masters wrote: >> There is a broader problem with X-Gene SPCR support. The problem is >> that the 16550 UART in X-Gene requires the 32-bit access quirk (the >> iotype is set to UPIO_MEM32 for the APMC0D08 device). This means >> that when univ8250_console_match runs later, it will compare the >> iotype (MEM32) with the type previously registered with the >> kernel when the earlycon setup the preferred console. > > Linaro has a kernel patch which looks at the bit_width field of the > port address: > > Author: Aleksey Makarov <aleksey.makarov@xxxxxxxxxx> > Date: Thu Apr 28 19:52:38 2016 +0300 > > serial: SPCR: check bit width for the 16550 UART > > The SPCR in 3.06.25 firmware has a bit_width field set to 32 and with the > above patch, I don't need to use console=. But HP firmware on m400 sets > bit width to 8 so that needs a firmware fix to work with above. Indeed, thanks. Graeme also mentioned that last night. I think this a good solution for the moment, but still that it makes sense to have a new 16650 UART type defined in the DBG2 spec for those requiring 32-bit access (to mirror the type D for pl011). I heard back from Microsoft this morning that they're looking. Jon. -- Computer Architect | Sent from my Fedora powered laptop -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
