Re: [PATCH] SPCR: check bit width for the 16550 UART
From: Duc Dang <hidden>
Date: 2016-12-05 18:52:04
Also in:
linux-acpi, lkml
On Mon, Dec 5, 2016 at 5:05 AM, Aleksey Makarov [off-list ref] 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-f521-927143f73d1e@redhat.com
Tested on X-Gene 1 and X-Gene 2 platforms. Tested-by: Duc Dang <redacted>
quoted hunk ↗ jump to hunk
Signed-off-by: Aleksey Makarov <redacted> Signed-off-by: Graeme Gregory <redacted> Reported-by: Heyi Guo <redacted> --- 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.