Re: [PATCH v6 1/5] qcom: spm: Add Subsystem Power Manager driver

[Lina Iyer <lina.iyer@linaro.org>]

On Fri, Sep 26 2014 at 10:59 -0600, Kevin Hilman wrote:
>Lina Iyer <lina.iyer@linaro.org> writes:
>
>> Based on work by many authors, available at codeaurora.org
>>
>> SPM is a hardware block that controls the peripheral logic surrounding
>> the application cores (cpu/l$). When the core executes WFI instruction,
>> the SPM takes over the putting the core in low power state as
>> configured. The wake up for the SPM is an interrupt at the GIC, which
>> then completes the rest of low power mode sequence and brings the core
>> out of low power mode.
>>
>> The SPM has a set of control registers that configure the SPMs
>> individually based on the type of the core and the runtime conditions.
>> SPM is a finite state machine block to which a sequence is provided and
>> it interprets the bytes  and executes them in sequence. Each low power
>> mode that the core can enter into is provided to the SPM as a sequence.
>>
>> Configure the SPM to set the core (cpu or L2) into its low power mode,
>> the index of the first command in the sequence is set in the SPM_CTL
>> register. When the core executes ARM wfi instruction, it triggers the
>> SPM state machine to start executing from that index. The SPM state
>> machine waits until the interrupt occurs and starts executing the rest
>> of the sequence until it hits the end of the sequence. The end of the
>> sequence jumps the core out of its low power mode.
>>
>> Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
>
>[...]
>
>> +enum {
>> +	MSM_SPM_REG_SAW2_CFG,
>> +	MSM_SPM_REG_SAW2_AVS_CTL,
>> +	MSM_SPM_REG_SAW2_AVS_HYSTERESIS,

>Do you really need the MSM_SPM_REG_ prefix on all of these?  As these
>names are all local to the driver, the extra prefix isn't needed IMO.
>
Nope, I dont.. I will remove them.

>Also, consdiering that SPM seems to be sub-block of SAW2, the fact that
>the SPM shows up twice in some of the names is a bit confusing.
>
I understand. I will fix that.

>