| 123456789101112131415161718192021222324252627282930313233343536373839404142434445 |
- From 814453adea7d081ad8917aa0f32d6a14165a3563 Mon Sep 17 00:00:00 2001
- From: Michal Simek <[email protected]>
- Date: Tue, 10 Apr 2018 15:32:28 +0200
- Subject: earlycon: Initialize port->uartclk based on clock-frequency property
- From: Michal Simek <[email protected]>
- 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 <[email protected]>
- [rmilecki: add -stable comment and Fixes tag]
- Signed-off-by: Rafał Miłecki <[email protected]>
- Signed-off-by: Greg Kroah-Hartman <[email protected]>
- ---
- 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,
|
