On Mon, Jun 21, 2021 at 9:27 PM Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> wrote: > > On Mon 21 Jun 20:00 CDT 2021, Jassi Brar wrote: > > > On Mon, Jun 21, 2021 at 6:35 PM Bjorn Andersson > > <bjorn.andersson@xxxxxxxxxx> wrote: > > > > > > On Mon 21 Jun 18:19 CDT 2021, Rob Herring wrote: > > > > > > > On Mon, Jun 21, 2021 at 5:10 PM Jassi Brar <jassisinghbrar@xxxxxxxxx> wrote: > > > > > > > > > > On Mon, Jun 21, 2021 at 2:46 PM Rob Herring <robh+dt@xxxxxxxxxx> wrote: > > > > > > > > > > > > On Sun, Jun 20, 2021 at 10:03 PM Jassi Brar <jassisinghbrar@xxxxxxxxx> wrote: > > > > > > > > > > > > > > On Sat, Jun 12, 2021 at 4:46 AM Martin Botka > > > > > > > <martin.botka@xxxxxxxxxxxxxx> wrote: > > > > > > > > > > > > > > > > This commit adds compatible for the SM6125 SoC > > > > > > > > > > > > > > > > Signed-off-by: Martin Botka <martin.botka@xxxxxxxxxxxxxx> > > > > > > > > --- > > > > > > > > Changes in V2: > > > > > > > > None > > > > > > > > Changes in V3: > > > > > > > > Change compatible to apcs-hmss-global > > > > > > > > drivers/mailbox/qcom-apcs-ipc-mailbox.c | 5 +++++ > > > > > > > > 1 file changed, 5 insertions(+) > > > > > > > > > > > > > > > > diff --git a/drivers/mailbox/qcom-apcs-ipc-mailbox.c b/drivers/mailbox/qcom-apcs-ipc-mailbox.c > > > > > > > > index f25324d03842..f24c5ad8d658 100644 > > > > > > > > --- a/drivers/mailbox/qcom-apcs-ipc-mailbox.c > > > > > > > > +++ b/drivers/mailbox/qcom-apcs-ipc-mailbox.c > > > > > > > > @@ -57,6 +57,10 @@ static const struct qcom_apcs_ipc_data sdm660_apcs_data = { > > > > > > > > .offset = 8, .clk_name = NULL > > > > > > > > }; > > > > > > > > > > > > > > > > +static const struct qcom_apcs_ipc_data sm6125_apcs_data = { > > > > > > > > + .offset = 8, .clk_name = NULL > > > > > > > > +}; > > > > > > > > + > > > > > > > > static const struct qcom_apcs_ipc_data apps_shared_apcs_data = { > > > > > > > > .offset = 12, .clk_name = NULL > > > > > > > > }; > > > > > > > > @@ -166,6 +170,7 @@ static const struct of_device_id qcom_apcs_ipc_of_match[] = { > > > > > > > > { .compatible = "qcom,sc8180x-apss-shared", .data = &apps_shared_apcs_data }, > > > > > > > > { .compatible = "qcom,sdm660-apcs-hmss-global", .data = &sdm660_apcs_data }, > > > > > > > > { .compatible = "qcom,sdm845-apss-shared", .data = &apps_shared_apcs_data }, > > > > > > > > + { .compatible = "qcom,sm6125-apcs-hmss-global", .data = &sm6125_apcs_data }, > > > > > > > > { .compatible = "qcom,sm8150-apss-shared", .data = &apps_shared_apcs_data }, > > > > > > > > { .compatible = "qcom,sdx55-apcs-gcc", .data = &sdx55_apcs_data }, > > > > > > > > {} > > > > > > > > > > > > > > > These all are basically different names for the same controller. > > > > > > > The 'offset' is a configuration parameter and the 'clock', when NULL, > > > > > > > is basically some "always-on" clock. > > > > > > > I am sure we wouldn't be doing it, if the controller was third-party. > > > > > > > > > > > > If newer implementations are 'the same', then they should have a > > > > > > fallback compatible to the existing one that is the same and no driver > > > > > > change is needed. If the differences are board or instance (within an > > > > > > SoC) specific, then a DT property would be appropriate. > > > > > > > > > > > The controllers (13 now) only differ by the 'offset' where the > > > > > registers are mapped. Clock-name is a pure s/w artifact. > > > > > So, maybe we could push all these in DT. > > > > > > > > Why is 'reg' not used for the offset? > > > > > > > > > > The DT node and its "reg" describes the whole IP block. > > > > > > The particular register that we care of has, as you can see, moved > > > around during the various platforms and some incarnations of this IP > > > block provides controls for CPU-related clocks as well. > > > > > > We can certainly have the multiple compatible points to the same > > > apcs_data, but I'm not able to spot a reasonable "catch-all compatible" > > > given that I don't see any natural groupings. > > > > > Any platform that comes later may reuse the already available compatible. > > For example drop this patch and reuse "qcom,sdm660-apcs-hmss-global" ? > > > > The problem is that this would change the meaning of > "qcom,sdm660-apcs-hmss-global" from meaning "The apcs hmss global block > _in_ sdm660" to "any random apcs block with the mailbox register at > offset 8". > To me, the deeper problem seems to be naming a controller "The apcs hmss global block _in_ sdm660" just because the h/w manual hasn't given a name to it. But that is okay too, if we name the subsequent controllers as "the same as one in sdm660" and provide the h/w configuration 'offset' via a DT property. > > > > In any case, we can't really get rid of the first 13 instances though... > > > > > > > > > > Right, we have the problem that we have DTBs out there that relies on > > > these compatibles, but as Jassi requests we'd have to start describing > > > the internal register layout in DT - which this binding purposefully > > > avoids. > > > > > Not these strings, but 'offset' and 'clock-name' as optional > > properties that new platforms can use. > > > > Relying on completely generic compatibles to match the driver and then > distinguish each platform using additional properties is exactly what > Qualcomm does downstream. The community has clarified countless times > that this is not the way to write DT bindings. > Yes, and I don't suggest it otherwise. For h/w quirks and extra/missing features, it does make sense to have different compatibles. However, for _trivial_ variations let us get that value from DT. 'offset' is anyway a h/w property. That way we won't be distinguishing platforms using dt properties, but only support different platforms seamlessly. On second thought, we have grown from 2 to 13 aliases in 4 yrs. I only have to ignore 3 times/annum to lead a peaceful life ;) thnx.