46 lines
1.8 KiB
Diff
46 lines
1.8 KiB
Diff
From 814453adea7d081ad8917aa0f32d6a14165a3563 Mon Sep 17 00:00:00 2001
|
|
From: Michal Simek <michal.simek@xilinx.com>
|
|
Date: Tue, 10 Apr 2018 15:32:28 +0200
|
|
Subject: earlycon: Initialize port->uartclk based on clock-frequency property
|
|
|
|
From: Michal Simek <michal.simek@xilinx.com>
|
|
|
|
commit 814453adea7d081ad8917aa0f32d6a14165a3563 upstream.
|
|
|
|
On DT based platforms when current-speed property is present baudrate
|
|
is setup. Also port->uartclk is initialized to bogus BASE_BAUD * 16
|
|
value. Drivers like uartps/ns16550 contain logic when baudrate and
|
|
uartclk is used for baudrate calculation.
|
|
|
|
The patch is reading optional clock-frequency property to replace bogus
|
|
BASE_BAUD * 16 calculation to have proper baudrate calculation.
|
|
|
|
[-stable comment: commit 31cb9a8575ca ("earlycon: initialise baud field
|
|
of earlycon device structure") has changed 8250_early.c behavior which
|
|
now tries to setup UART speed. Ignoring clock-frequency results in
|
|
wrong value of calculated divisor & malformed early console output.]
|
|
|
|
Fixes: 31cb9a8575ca ("earlycon: initialise baud field of earlycon device structure")
|
|
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
|
|
[rmilecki: add -stable comment and Fixes tag]
|
|
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
|
|
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
|
|
---
|
|
drivers/tty/serial/earlycon.c | 4 ++++
|
|
1 file changed, 4 insertions(+)
|
|
|
|
--- a/drivers/tty/serial/earlycon.c
|
|
+++ b/drivers/tty/serial/earlycon.c
|
|
@@ -289,6 +289,10 @@ int __init of_setup_earlycon(const struc
|
|
if (val)
|
|
early_console_dev.baud = be32_to_cpu(*val);
|
|
|
|
+ val = of_get_flat_dt_prop(node, "clock-frequency", NULL);
|
|
+ if (val)
|
|
+ port->uartclk = be32_to_cpu(*val);
|
|
+
|
|
if (options) {
|
|
early_console_dev.baud = simple_strtoul(options, NULL, 0);
|
|
strlcpy(early_console_dev.options, options,
|