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    SubjectRe: [PATCH 07/18] drivers: firmware: psci: Prepare to use OS initiated suspend mode
    On Fri, 7 Jun 2019 at 17:17, Sudeep Holla <sudeep.holla@arm.com> wrote:
    >
    > On Mon, May 13, 2019 at 09:22:49PM +0200, Ulf Hansson wrote:
    > > The per CPU variable psci_power_state, contains an array of fixed values,
    > > which reflects the corresponding arm,psci-suspend-param parsed from DT, for
    > > each of the available CPU idle states.
    > >
    > > This isn't sufficient when using the hierarchical CPU topology in DT in
    > > combination with having PSCI OS initiated (OSI) mode enabled. More
    > > precisely, in OSI mode, Linux is responsible of telling the PSCI FW what
    > > idle state the cluster (a group of CPUs) should enter, while in PSCI
    > > Platform Coordinated (PC) mode, each CPU independently votes for an idle
    > > state of the cluster.
    > >
    > > For this reason, let's introduce an additional per CPU variable called
    > > domain_state and implement two helper functions to read/write its values.
    > > Following patches, which implements PM domain support for PSCI, will use
    > > the domain_state variable and set it to corresponding bits that represents
    > > the selected idle state for the cluster.
    > >
    > > Finally, in psci_cpu_suspend_enter() and psci_suspend_finisher(), let's
    > > take into account the values in the domain_state, as to get the complete
    > > suspend parameter.
    > >
    >
    > I understand it was split to ease review, but this patch also does
    > nothing as domain_state = 0 always. I was trying hard to find where it's
    > set, but I assume it will be done in later patches. Again may be this
    > can be squashed into the first caller of psci_set_domain_state

    You have a point, but I am worried that it would look like this series
    is solely needed to support OSI mode. This is not the case. Let me
    explain.

    Having $subject patch separate shows the specific changes needed to
    support OSI mode. The first caller of psci_set_domain_state() is added
    in patch9, however, patch9 is useful no matter of OSI or PC mode.

    Moreover, if I squash $subject patch with patch9, I would have to
    squash also the subsequent patch (patch8), as it depends on $subject
    patch.

    So, to conclude, are you happy with this as is or do you want me to
    squash the patches?

    Kind regards
    Uffe

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