[PATCH v2 4/6] reset: anlogic: add support for Anlogic DR1V90 resets

Junhui Liu junhui.liu at pigmoral.tech
Tue Oct 28 04:29:05 PDT 2025


Hi Philipp,
Thanks for your review.

On 10/28/25 4:17 PM, Philipp Zabel wrote:
> On So, 2025-10-26 at 22:00 +0800, Junhui Liu wrote:
>> Add reset controller support for the Anlogic DR1V90 SoC, which is an
>> auxiliary device associated with the Clock and Reset Unit (CRU). All
>> resets are active-low.
>>
>> Signed-off-by: Junhui Liu <junhui.liu at pigmoral.tech>
>> ---
>>   drivers/reset/Kconfig        |   9 +++
>>   drivers/reset/Makefile       |   1 +
>>   drivers/reset/reset-dr1v90.c | 135 +++++++++++++++++++++++++++++++++++++++++++
>>   3 files changed, 145 insertions(+)
>>
> [...]
>> diff --git a/drivers/reset/reset-dr1v90.c b/drivers/reset/reset-dr1v90.c
>> new file mode 100644
>> index 0000000000000000000000000000000000000000..eb9064e3ab454fb39adc1ad426f458e39bb6169e
>> --- /dev/null
>> +++ b/drivers/reset/reset-dr1v90.c
>> @@ -0,0 +1,135 @@
> [...]
>> +static const struct dr1v90_reset_map dr1v90_resets[] = {
>> +	[RESET_OCM]		= { 0x74, BIT(4)},
> [...]
>> +	[RESET_NIC_HP0]		= { 0x78, BIT(0)},
> [...]
>> +	[RESET_USB0]		= { 0x7C, BIT(0)},
> The registers 0x74, 0x78, and 0x7C are exclusively used for resets?

Yes, these three registers only contain bits for resets according to the
register list doc.

>
> [...]
>> +};
>> +
>> +static int dr1v90_reset_control_update(struct reset_controller_dev *rcdev,
>> +				       unsigned long id, bool assert)
>> +{
>> +	struct dr1v90_reset_controller *rstc = to_dr1v90_reset_controller(rcdev);
>> +	u32 offset = dr1v90_resets[id].offset;
>> +	u32 bit = dr1v90_resets[id].bit;
>> +	u32 reg;
>> +
>> +	reg = readl(rstc->base + offset);
>> +	if (assert)
>> +		reg &= ~bit;
>> +	else
>> +		reg |= bit;
>> +	writel(reg, rstc->base + offset);
> There should be a lock around this read-modify-write access.

Okay, I will add a lock in the next version.

>
> regards
> Philipp

-- 
Best regards,
Junhui Liu




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