[PATCH 2/2] hwrng: msm: add ACPI support

Timur Tabi
2018-06-22T04:26:37Z

On 6/21/18 11:23 PM, Vinod wrote:
> On 21-06-18, 10:17, Timur Tabi wrote:
>> Add support for probing on ACPI systems, with ACPI HID QCOM8160.
>>
>> On ACPI systems, clocks are always enabled, the PRNG should
>> already be enabled, and the register region is read-only.
>> The driver only verifies that the hardware is already
>> enabled never tries to disable or configure it.
>
> so if you are using v2 hardware, are you pointing to High Level OS EE or
> some other..?

I'm not sure what you mean.

>> + /*
>> + * ACPI systems have v2 hardware. The clocks are always enabled,
>> + * the PRNG register space is read-only, and the PRNG should
>> + * already be enabled.
>> + */
>> + if (has_acpi_companion(&pdev->dev)) {
>> + u32 val;
>> +
>> + val = readl(rng->base + PRNG_CONFIG);
>
> v2 EEs dont seem to have CONFIG register, so not sure about this one

I can post the register set, but this works on my silicon. The first
device has all the registers. Then there are about 12-13 other devices
with their own 64K register regions, and those don't have a config
register.

I don't know why you would choose to support a one of the secondary
register sets when you can use the primary.