[PATCH linux dev-4.7] arm: aspeed: romulus: Do common setup

[Joel Stanley]

On Mon, Feb 20, 2017 at 2:19 PM, Mine <mine260309 at gmail.com> wrote:
> Hi Joel,
>
> On Mon, Feb 20, 2017 at 8:15 AM, Joel Stanley <joel at jms.id.au> wrote:
>> Hi Lei,
>>
>> On Sun, Feb 19, 2017 at 12:06 AM, Mine <mine260309 at gmail.com> wrote:
>>> I thought do_common_setup() is called by default, but actually it's not.
>>> So Romulus needs to call do_common_setup() as well.
>>
>> We don't need most of what this is doing on any platform.
>>
>>>        /* Enable LPC FWH cycles, Enable LPC to AHB bridge */
>>>        writel(0x00000500, AST_IO(AST_BASE_LPC | 0x80));
>>
>> This is performed by the LPC driver that Cyril has written.
>>
>>>        /* Set UART routing */
>>>        writel(0x00000000, AST_IO(AST_BASE_LPC | 0x9c));
>>
>> This is the default. If we need to change it in the future we might
>> write a pinmux driver, but for now we could omit this.
>>
>>>        /* Setup scratch registers */
>>>        writel(0x00000042, AST_IO(AST_BASE_LPC | 0x170));
>>>        writel(0x00008000, AST_IO(AST_BASE_LPC | 0x174));
>>
>> We don't have a driver for this. Andrew was thinking about a UIO
>> driver. Ben started a discussion[1] upstream about the preferred
>> approach.
>
> It means for now they are needed, before the UIO driver is implemented, is it?
> So I assume Romulus will need do_common_setup() anyway, at least for
> the current kernel.
> Otherwise I'm afraid the VUART may not work since it requires register 0x174 to
> be set to 0x00008000.

Okay. We can include this one for now while the UIO driver is developed.

Applied to dev-4.7.

Cheers,

Joel

>
>>
>> [1] https://lkml.org/lkml/2017/2/17/30
>>
>> Cheers,
>>
>> Joel
>>
>>>
>>> --
>>> BRs,
>>> Lei YU
>>>
>>> On Sat, Feb 18, 2017 at 9:33 PM, Lei YU <mine260309 at gmail.com> wrote:
>>>> Call do_common_setup for romulus.
>>>> No other romulus specific setup is needed.
>>>> Consider moving do_common_setup() to a common place.
>>>>
>>>> Signed-off-by: Lei YU <mine260309 at gmail.com>
>>>> ---
>>>>  arch/arm/mach-aspeed/aspeed.c | 7 +++++++
>>>>  1 file changed, 7 insertions(+)
>>>>
>>>> diff --git a/arch/arm/mach-aspeed/aspeed.c b/arch/arm/mach-aspeed/aspeed.c
>>>> index 2a11c2e..726b8fa 100644
>>>> --- a/arch/arm/mach-aspeed/aspeed.c
>>>> +++ b/arch/arm/mach-aspeed/aspeed.c
>>>> @@ -218,6 +218,11 @@ static void __init do_witherspoon_setup(void)
>>>>         writel(0x68600000, AST_IO(AST_BASE_SPI | 0x30));
>>>>  }
>>>>
>>>> +static void __init do_romulus_setup(void)
>>>> +{
>>>> +       do_common_setup();
>>>> +}
>>>> +
>>>>  #define SCU_PASSWORD   0x1688A8A8
>>>>
>>>>  static void __init aspeed_init_early(void)
>>>> @@ -253,6 +258,8 @@ static void __init aspeed_init_early(void)
>>>>                 do_zaius_setup();
>>>>         if (of_machine_is_compatible("ibm,witherspoon-bmc"))
>>>>                 do_witherspoon_setup();
>>>> +       if (of_machine_is_compatible("ibm,romulus-bmc"))
>>>> +               do_romulus_setup();
>>>>  }
>>>>
>>>>  static void __init aspeed_map_io(void)
>>>> --
>>>> 1.9.1
>>>>