[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
More information about the linux-riscv
mailing list