[U-Boot] [PATCH 1/2] serial: dcc: Move driver to DM

[Simon Glass]

Hi Michal,

On 22 February 2016 at 08:54, Michal Simek <michal.simek at xilinx.com> wrote:
> On 19.2.2016 21:55, Simon Glass wrote:
>> Hi Michal,
>>
>> On 18 February 2016 at 09:01, Michal Simek <michal.simek at xilinx.com> wrote:
>>> Enabling this driver requires some DT changes.
>>> Adding DCC to root or main bus:
>>> dcc: dcc {
>>>         compatible = "arm,dcc";
>>>         u-boot,dm-pre-reloc;
>>> };
>>>
>>> Extend alias list to link DCC:
>>>         serial0 = &uart0;
>>>         serial1 = &uart1;
>>>         serial2 = &dcc;
>>>
>>> Change stdout-path to point to dcc port.
>>>         stdout-path = "serial2:115200n8";
>>>
>>> Also add support for debug uart to help with early debug.
>>>
>>> Signed-off-by: Michal Simek <michal.simek at xilinx.com>
>>> ---
>>>
>>>  drivers/serial/Kconfig   |  5 ++++
>>>  drivers/serial/arm_dcc.c | 63 +++++++++++++++++++++++++++++-------------------
>>>  2 files changed, 43 insertions(+), 25 deletions(-)
>>>
>>> diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
>>> index fac317610e2a..7c18a6218b1f 100644
>>> --- a/drivers/serial/Kconfig
>>> +++ b/drivers/serial/Kconfig
>>> @@ -119,6 +119,11 @@ config DEBUG_UART_UARTLITE
>>>           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_ARM_DCC
>>> +       bool "ARM DCC"
>>> +       help
>>> +         Select this to enable a debug UART using the ARM DCC port.
>>
>> Can you please expand this - what is DCC? What parts support it? What is it for?
>
> Sure will do.
>
>>
>>> +
>>>  config DEBUG_UART_ZYNQ
>>>         bool "Xilinx Zynq"
>>>         help
>>> diff --git a/drivers/serial/arm_dcc.c b/drivers/serial/arm_dcc.c
>>> index 4624666e8a2c..07981e18ee49 100644
>>> --- a/drivers/serial/arm_dcc.c
>>> +++ b/drivers/serial/arm_dcc.c
>>> @@ -1,6 +1,7 @@
>>>  /*
>>>   * Copyright (C) 2004-2007 ARM Limited.
>>>   * Copyright (C) 2008 Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
>>> + * Copyright (C) 2015 - 2016 Xilinx, Inc, Michal Simek
>>>   *
>>>   * SPDX-License-Identifier:    GPL-2.0
>>>   *
>>> @@ -16,6 +17,7 @@
>>>   */
>>>
>>>  #include <common.h>
>>> +#include <dm.h>
>>>  #include <serial.h>
>>>
>>>  #if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V7)
>>> @@ -94,12 +96,7 @@
>>>
>>>  #define TIMEOUT_COUNT 0x4000000
>>>
>>> -static int arm_dcc_init(void)
>>> -{
>>> -       return 0;
>>> -}
>>> -
>>> -static int arm_dcc_getc(void)
>>> +static int arm_dcc_getc(struct udevice *dev)
>>>  {
>>>         int ch;
>>>         register unsigned int reg;
>>> @@ -112,7 +109,7 @@ static int arm_dcc_getc(void)
>>>         return ch;
>>>  }
>>>
>>> -static void arm_dcc_putc(char ch)
>>> +static int arm_dcc_putc(struct udevice *dev, char ch)
>>>  {
>>>         register unsigned int reg;
>>>         unsigned int timeout_count = TIMEOUT_COUNT;
>>> @@ -123,41 +120,57 @@ static void arm_dcc_putc(char ch)
>>>                         break;
>>>         }
>>>         if (timeout_count == 0)
>>> -               return;
>>> +               return -EAGAIN;
>>>         else
>>>                 write_dcc(ch);
>>> +
>>> +       return 0;
>>>  }
>>>
>>> -static int arm_dcc_tstc(void)
>>> +static int arm_dcc_pending(struct udevice *dev, bool input)
>>>  {
>>>         register unsigned int reg;
>>>
>>> -       can_read_dcc(reg);
>>> +       if (input) {
>>
>> Don't need the {} here
>>
>>> +               can_read_dcc(reg);
>>> +       } else {
>>> +               can_write_dcc(reg);
>>> +       }
>
> Unfortunately I do. can_read/write_dcc are macros.

What goes wrong if you leave them out? But if you need them, that's OK.

>
> Thanks,
> Michal

Regards,
Simon