Re: [PATCH 1/2] serial: support register interface with 16-bit stride for console

Hi Peter,

2015-10-20 4:50 GMT+09:00 Peter Hurley [off-list ref]:

On 10/19/2015 01:40 AM, Masahiro Yamada wrote:

quoted

Currently, 8-bit (MMIO) and 32-bit (MMIO32) strides are supported for
the 8250 console, but 16-bit (MMIO16) stride is not.  The 8250 UART
device on my board has 16-bit stride (reg-shift = <1>) and I am eager
to use earlycon with it.

Refer to arch/arm/boot/dts/uniphier-support-card.dtsi:

        serialsc: uart@000b0000 {
                compatible = "ns16550a";
                reg = <0x000b0000 0x20>;
                clock-frequency = <12288000>;
                reg-shift = <1>;
        };

Signed-off-by: Masahiro Yamada <redacted>
---

 Documentation/kernel-parameters.txt  |  9 +++++----
 drivers/tty/serial/8250/8250_early.c |  5 +++++
 drivers/tty/serial/8250/8250_port.c  | 20 ++++++++++++++++++++
 drivers/tty/serial/earlycon.c        | 15 +++++++++++----
 drivers/tty/serial/serial_core.c     |  9 +++++++--
 include/linux/serial_core.h          |  1 +
 include/uapi/linux/serial.h          |  9 +++++----
 7 files changed, 54 insertions(+), 14 deletions(-)

[...]

quoted

diff --git a/include/uapi/linux/serial.h b/include/uapi/linux/serial.h
index 25331f9..1d20d9c 100644
--- a/include/uapi/linux/serial.h
+++ b/include/uapi/linux/serial.h

@@ -65,10 +65,11 @@ struct serial_struct {
 #define SERIAL_IO_PORT       0
 #define SERIAL_IO_HUB6       1
 #define SERIAL_IO_MEM        2
-#define SERIAL_IO_MEM32        3
-#define SERIAL_IO_AU   4
-#define SERIAL_IO_TSI          5
-#define SERIAL_IO_MEM32BE 6
+#define SERIAL_IO_MEM16      3
+#define SERIAL_IO_MEM32        4
+#define SERIAL_IO_AU   5
+#define SERIAL_IO_TSI          6
+#define SERIAL_IO_MEM32BE 7

The existing values cannot be re-defined since they're userspace visible.

Thanks, I've sent v2.


-- 
Best Regards
Masahiro Yamada