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: [PATCH] earlycon: Initialize port->uartclk based on clock-frequency property
Git-commit: 814453adea7d081ad8917aa0f32d6a14165a3563
Patch-mainline: v4.18-rc1
References: bsc#1051510
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.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/tty/serial/earlycon.c | 4 ++++
1 file changed, 4 insertions(+)
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -285,6 +285,10 @@ int __init of_setup_earlycon(const struc
}
}
+ val = of_get_flat_dt_prop(node, "clock-frequency", NULL);
+ if (val)
+ port->uartclk = be32_to_cpu(*val);
+
if (options) {
strlcpy(early_console_dev.options, options,
sizeof(early_console_dev.options));