List
Description:
UART register contents: timeout=0 rxfifo_level=56, should be timeout=10 rxfifo_level=56
minicom prints 56 symbols at a time when rxfifo reaches its level.
remembers all typed symbols
sometimes the timeout register is set correctly
Possible reason:
In driver .startup and .termios conflict? Racing Resets or reset takes time?
Solution:
Added a delay after reset - some other functions in the driver also have it - some not. Luck?
Patch:
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index f214c7f..164e32d 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -704,6 +704,9 @@ static void cdns_uart_set_termios(struct uart_port *port,
ctrl_reg |= CDNS_UART_CR_TXRST | CDNS_UART_CR_RXRST;
cdns_uart_writel(ctrl_reg, CDNS_UART_CR_OFFSET);
+ while (cdns_uart_readl(CDNS_UART_CR_OFFSET) &
+ (CDNS_UART_CR_TXRST | CDNS_UART_CR_RXRST))
+ cpu_relax();
/*
* Clear the RX disable and TX disable bits and then set the TX enable
* bit and RX enable bit to enable the transmitter and receiver.
Links:
* https://forums.xilinx.com/t5/Zynq-All-Programmable-SoC/Zynq-Uart-timeout-problem/td-p/432016
* http://www.makelinux.net/ldd3/chp-7-sect-3
Description:
Freezes, lags but remembers all typed symbols
Possible reason:
Bad network cable? Network problem?
Too many messages when rtc is missing
Description:
3x"hwclock: can't open '/dev/misc/rtc': No such file or directory" in boot log
Possible reason:
driver
- U-boot Falcon mode (boot from SPL directly to OS avoiding full u-boot)
Description:
Investigate the option
Possible reason:
Useful pages