[U-Boot] [PATCH 2/3] serial: uartlite: Add support for debug console

Michal Simek
2015-12-14T15:50:11Z

Hi,

On 14.12.2015 14:14, Thomas Chou wrote:
> Hi Michal,
>
> On 2015?12?11? 19:54, Michal Simek wrote:
>> Signed-off-by: Michal Simek <michal.simek@xilinx.com>
>> ---
>>
>> drivers/serial/Kconfig | 7 +++++++
>> drivers/serial/serial_xuartlite.c | 23 +++++++++++++++++++++++
>> 2 files changed, 30 insertions(+)
>>
>> diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
>> index 1fc287ee98ec..f1e221799b81 100644
>> --- a/drivers/serial/Kconfig
>> +++ b/drivers/serial/Kconfig
>> @@ -92,6 +92,13 @@ config DEBUG_UART_S5P
>> will need to provide parameters to make this work. The driver
>> will
>> be available until the real driver-model serial is running.
>>
>> +config DEBUG_UART_UARTLITE
>> + bool "Xilinx Uartlite"
>> + help
>> + Select this to enable a debug UART using the serial_uartlite
>> driver.
>> + You will need to provide parameters to make this work. The
>> driver will
>> + be available until the real driver-model serial is running.
>> +
>> config DEBUG_UART_ZYNQ
>> bool "Xilinx Zynq"
>> help
>> diff --git a/drivers/serial/serial_xuartlite.c
>> b/drivers/serial/serial_xuartlite.c
>> index 10089f5a34b5..fe87b515d902 100644
>> --- a/drivers/serial/serial_xuartlite.c
>> +++ b/drivers/serial/serial_xuartlite.c
>> @@ -120,3 +120,26 @@ U_BOOT_DRIVER(serial_uartlite) = {
>> .ops = &uartlite_serial_ops,
>> .flags = DM_FLAG_PRE_RELOC,
>> };
>> +
>> +#ifdef CONFIG_DEBUG_UART_UARTLITE
>
> Better move the "#include <debug_uart.h>" here.

This is the patch I sent some days ago about removing it from this
location and it was Reviewed twice.
http://lists.denx.de/pipermail/u-boot/2015-December/236341.html

>
>> +void _debug_uart_init(void)
>
> Please add "static inline" to void _debug_uart_init(void).

Ok. Will fix this for uartlite and zynq uart in follow up patch.

>> +{
>> + struct uartlite *regs = (struct uartlite *)CONFIG_DEBUG_UART_BASE;
>> +
>> + out_be32(&regs->control, 0);
>> + out_be32(&regs->control, ULITE_CONTROL_RST_RX |
>> ULITE_CONTROL_RST_TX);
>> + in_be32(&regs->control);
>> +}
>> +
>> +static inline void _debug_uart_putc(int ch)
>> +{
>> + struct uartlite *regs = (struct uartlite *)CONFIG_DEBUG_UART_BASE;
>> +
>> + while (in_be32(&regs->status) & SR_TX_FIFO_FULL)
>> + WATCHDOG_RESET();
>
> WATCHDOG_RESET() is not really needed for debug serial output.

TBH I don't think so. There could be watchdog running from early
bootloader and needs to be service even for debugging purpose.

Thanks,
Michal