Re: [PATCH 4/9] interconnect: qcom: icc-rpm: allow overwriting get_bw callback

[Dmitry Baryshkov]

On Tue, Mar 24, 2026 at 12:34:35PM +0100, Konrad Dybcio wrote:
> On 3/24/26 12:14 AM, Dmitry Baryshkov wrote:
> > On Mon, Mar 23, 2026 at 11:32:33AM +0100, Konrad Dybcio wrote:
> >> On 3/23/26 2:17 AM, Dmitry Baryshkov wrote:
> >>> MSM8974 requires a separate get_bw callback, since on that platform
> >>> increasing the clock rate for some of the NoCs during boot may lead to
> >>> hangs. For the details see commit 9caf2d956cfa ("interconnect: qcom:
> >>> msm8974: Don't boost the NoC rate during boot").
> >>
> >> Is there a single specific bus where this causes an issue, or is
> >> setting *any* resource to INT_MAX problematic?
> > 
> > I'd refer this to Luca. I didn't experiment that much (and also note,
> > this behaviour might be firmware-specific).
> 
> In case anyone's interested, it _seems like_ it's
> 
> (RPM_KEY_BW + RPM_BUS_MASTER_REQ/RPM_BUS_SLAVE_REQ) failing with certain
> nodes

Yes. And if you check, these nodes have QoS settings in the DT. Later
kernels have added a guard check (.qos.ap_owned) and dropped mas/slv IDs
for similar nodes.

> > My goal for this patchset was to port as close as possible. We can drop
> > the get_bw later, after enabling more interconnects, writing the QoS,
> > etc.
> 
> That's fine

Rb?

-- 
With best wishes
Dmitry