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

[Michal Simek <michal.simek@xilinx.com>]

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