On Mon, Dec 5, 2016 at 5:05 AM, Aleksey Makarov <aleksey.maka...@linaro.org> wrote: > Check the 'Register Bit Width' field of the ACPI Generic Address > Structure that specifies the address of the UART registers to > decide if the driver should use "mmio32" access instead of "mmio". > > If the driver is other than 16550 the access with is defined > by the Interface Type field of the SPCR table. > > For discussion: > > https://lkml.kernel.org/r/7fa523de-3fbb-1566-f521-927143f73...@redhat.com
Tested on X-Gene 1 and X-Gene 2 platforms. Tested-by: Duc Dang <dhd...@apm.com> > > Signed-off-by: Aleksey Makarov <aleksey.maka...@linaro.org> > Signed-off-by: Graeme Gregory <graeme.greg...@linaro.org> > Reported-by: Heyi Guo <heyi....@linaro.org> > --- > drivers/acpi/spcr.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/acpi/spcr.c b/drivers/acpi/spcr.c > index e8d7bc7..6c6710b 100644 > --- a/drivers/acpi/spcr.c > +++ b/drivers/acpi/spcr.c > @@ -70,6 +70,10 @@ int __init parse_spcr(bool earlycon) > break; > case ACPI_DBG2_16550_COMPATIBLE: > case ACPI_DBG2_16550_SUBSET: > + if (table->serial_port.space_id == > + ACPI_ADR_SPACE_SYSTEM_MEMORY && > + table->serial_port.bit_width == 32) > + iotype = "mmio32"; > uart = "uart"; > break; > default: > -- > 2.10.2 > Thanks, Duc Dang.
