diff options
author | Kinsey Moore <kinsey.moore@oarcorp.com> | 2021-03-12 09:59:40 -0600 |
---|---|---|
committer | Joel Sherrill <joel@rtems.org> | 2021-04-19 10:51:02 -0500 |
commit | 3ea43bc9e7e1ace798534fabc40326f69f9b18e8 (patch) | |
tree | 2cc65701a92e4914a3d9fe5990aede08d7300479 /bsps | |
parent | rtems: Document rtems_semaphore_obtain() errors (diff) | |
download | rtems-3ea43bc9e7e1ace798534fabc40326f69f9b18e8.tar.bz2 |
bsps/xilinx-zynqmp: Avoid constant UART reinit
Constantly reinitializing the Cadence UART on every character output
causes data corruption/loss on some ZynqMP hardware. Only initialize
the UART once for early output and give it a kick on startup.
Diffstat (limited to 'bsps')
-rw-r--r-- | bsps/aarch64/xilinx-zynqmp/console/console.c | 6 | ||||
-rw-r--r-- | bsps/shared/dev/serial/zynq-uart-polled.c | 9 |
2 files changed, 12 insertions, 3 deletions
diff --git a/bsps/aarch64/xilinx-zynqmp/console/console.c b/bsps/aarch64/xilinx-zynqmp/console/console.c index 84e158d3f6..9886a117dc 100644 --- a/bsps/aarch64/xilinx-zynqmp/console/console.c +++ b/bsps/aarch64/xilinx-zynqmp/console/console.c @@ -112,6 +112,12 @@ static void zynqmp_debug_console_early_init(char c) &zynqmp_uart_instances[BSP_CONSOLE_MINOR].base; zynq_uart_initialize(base); + BSP_output_char = zynqmp_debug_console_out; + /* + * Some ZynqMP UARTs have a hardware bug that causes TX/RX logic restarts to + * require a kick after baud rate registers are initialized. + */ + zynqmp_debug_console_out(0); zynqmp_debug_console_out(c); } diff --git a/bsps/shared/dev/serial/zynq-uart-polled.c b/bsps/shared/dev/serial/zynq-uart-polled.c index 442431d502..74e7255ec2 100644 --- a/bsps/shared/dev/serial/zynq-uart-polled.c +++ b/bsps/shared/dev/serial/zynq-uart-polled.c @@ -128,14 +128,17 @@ void zynq_uart_initialize(rtems_termios_device_context *base) regs->control &= ~(ZYNQ_UART_CONTROL_RXEN | ZYNQ_UART_CONTROL_TXEN); regs->control = ZYNQ_UART_CONTROL_RXDIS - | ZYNQ_UART_CONTROL_TXDIS - | ZYNQ_UART_CONTROL_RXRES - | ZYNQ_UART_CONTROL_TXRES; + | ZYNQ_UART_CONTROL_TXDIS; regs->mode = ZYNQ_UART_MODE_CHMODE(ZYNQ_UART_MODE_CHMODE_NORMAL) | ZYNQ_UART_MODE_PAR(ZYNQ_UART_MODE_PAR_NONE) | ZYNQ_UART_MODE_CHRL(ZYNQ_UART_MODE_CHRL_8); regs->baud_rate_gen = ZYNQ_UART_BAUD_RATE_GEN_CD(brgr); regs->baud_rate_div = ZYNQ_UART_BAUD_RATE_DIV_BDIV(bauddiv); + /* A Tx/Rx logic reset must be issued after baud rate manipulation */ + regs->control = ZYNQ_UART_CONTROL_RXDIS + | ZYNQ_UART_CONTROL_TXDIS + | ZYNQ_UART_CONTROL_RXRES + | ZYNQ_UART_CONTROL_TXRES; regs->rx_fifo_trg_lvl = ZYNQ_UART_RX_FIFO_TRG_LVL_RTRIG(0); regs->rx_timeout = ZYNQ_UART_RX_TIMEOUT_RTO(0); regs->control = ZYNQ_UART_CONTROL_RXEN |