Re: [RFC PATCH v2 1/9] mailbox: Add Amlogic Meson Message-Handling-Unit

From: Neil Armstrong
Date: Thu Jun 23 2016 - 08:51:13 EST


On 06/22/2016 06:31 AM, Jassi Brar wrote:
> On Tue, Jun 21, 2016 at 3:32 PM, Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:
>> Add Amlogic Meson SoCs Message-Handling-Unit as mailbox controller
>> with 2 independent channels/links to communicate with a remote processor.
>>
>> Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
>
> .....
>
>> +++ b/drivers/mailbox/meson_mhu.c
>> @@ -0,0 +1,199 @@
>> +/*
>> + * Copyright (C) 2016 BayLibre SAS.
>> + * Author: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
>> + * Heavily based on meson_mhu.c from :
>> + * Copyright (C) 2013-2015 Fujitsu Semiconductor Ltd.
>> + * Copyright (C) 2015 Linaro Ltd.
>> + * Author: Jassi Brar <jaswinder.singh@xxxxxxxxxx>
>
> .........
>> +
>> +#define INTR_SET_OFS 0x0
>> +#define INTR_STAT_OFS 0x4
>> +#define INTR_CLR_OFS 0x8
>> +
>> +#define MHU_LP_OFFSET 0x10
>> +#define MHU_HP_OFFSET 0x1c
>> +
>> +#define TX_REG_OFFSET 0x24
>> +
> It seems only some register offsets have changed from arm_mhu. So
> maybe just adapt the arm_mhu driver to look for IP variant and assign
> corresponding offsets to set,stat,clr registers.

Hi Jassi,

It's a good idea, but adding the platform_driver support along the amba_bus probe will add a lot a code.
The meson_mhu is a very simple and short driver, I think it'll be simpler to maintain beeing separated.
And I'm not certain on how it's close of ARM's real IP.

Neil

> Cheers.
>