[U-Boot] [PATCH v5 01/16] arm: socfpga: Restructure clock manager driver

[Marek Vasut]

On 04/17/2017 09:20 AM, Ley Foon Tan wrote:
> On Fri, Apr 14, 2017 at 6:15 PM, Marek Vasut <marex at denx.de> wrote:
>> On 04/13/2017 07:41 PM, Ley Foon Tan wrote:
>>> Restructure clock manager driver in the preparation to support A10.
>>> Move the Gen5 specific code to _gen5 files.
>>>
>>> - Change all uint32_t to u32 and change to use macro BIT(n) for bit shift.
>>> - Check return value from wait_for_bit(). So change return type to int for
>>>   cm_write_with_phase() and cm_basic_init().
>>>
>>> Signed-off-by: Ley Foon Tan <ley.foon.tan at intel.com>
>>
>> [...]
>>
>>>  /* function to write a clock register that has phase information */
>>> -static void cm_write_with_phase(uint32_t value,
>>> -                             uint32_t reg_address, uint32_t mask)
>>> +static int cm_write_with_phase(u32 value, u32 reg_address, u32 mask)
>>>  {
>>> +     int ret;
>>> +
>>>       /* poll until phase is zero */
>>> -     while (readl(reg_address) & mask)
>>> -             ;
>>> +     ret = wait_for_bit(__func__, (const u32 *)reg_address, mask,
>>> +                        false, 20000, false);
>>> +     if (ret)
>>> +             return ret;
>>>
>>>       writel(value, reg_address);
>>>
>>> -     while (readl(reg_address) & mask)
>>> -             ;
>>> +     return wait_for_bit(__func__, (const u32 *)reg_address, mask,
>>> +                         false, 20000, false);
>>>  }
>>>
>>
>> Could it be that this active wait is here so that it'd work without an
>> initialized timer ? Because at this point, you don't have timer and I
>> think wait_for_bit() uses timer.
>>
> Timer is initialized before calling to this function. So, should be no problem.
> 
> In arch/arm/mach-socfpga/spl.c, timer is initialized before calling to
> cm_basic_init(). Note, cm_write_with_phase() is called by
> cm_basic_init().
> 
> socfpga_per_reset(SOCFPGA_RESET(OSC1TIMER0), 0);
> 
> timer_init();
> 
> debug("Reconfigure Clock Manager\n");
> /* reconfigure the PLLs */
> if (cm_basic_init(cm_default_cfg))
>           hang();

OK, perfect.

-- 
Best regards,
Marek Vasut