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

Michal Simek michal.simek at xilinx.com
Mon Feb 22 16:54:27 CET 2016


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.

Thanks,
Michal


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