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

[Timur Tabi <timur@codeaurora.org>]

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.


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