Caleb Connolly caleb.connolly@linaro.org writes:
On 11/03/2024 18:23, Volodymyr Babchuk wrote:
Hi Caleb, Caleb Connolly caleb.connolly@linaro.org writes:
On 06/03/2024 21:24, Volodymyr Babchuk wrote:
Hi Caleb,
Caleb Connolly caleb.connolly@linaro.org writes:
[...]
>> +}; >> + >> +&tlmm { >> + /* U-Boot pinctrl driver does not understand multiple tiles */ >> + reg = <0x0 0x03000000 0x0 0x1000000>; >> + /delete-property/ reg-names; > > This won't be needed if we can make the tiles offset in the pinctrl > driver compatible: > > #define WEST 0x00000000 > #define EAST 0x00400000 > #define NORTH 0x00800000 > #define SOUTH 0x00C00000
Hmm, I assume that in this case pinctrl driver should map all the four tiles independently? Are there guarantees in U-Boot that four separate memory regions will be mapped into virtual memory with the same relative positions? Linux clearly don't make such guarantees.
U-Boot doesn't use virtual addresses on arm platforms, it only goes as far as reading the address from DT, nothing else, so this is totally fine and is how the other SoCs do it.
For me it looks like we are depending on implementation details knowledge. I.e MMU API does not provide such guarantees, but drivers know how ARM MMU code is working internally and drivers depend on exactly this behavior. But if you are saying that it is totally fine, I'll rework the patch. No big deal. Actually, I already tried this and it is working fine.
>> + >> + /* U-Boot ethernet driver wants to drive reset as GPIO */ >> + /delete-node/ phy-reset-pins; > > I suppose this is not needed as phy-reset-pins also configures the pin > as GPIO only. > Well, yes. This also puzzles me up, but for some reason it stops working if I leave this node intact. Looks like I need to look at this deeper before posting the next version.
Possibly the pinconf defined in the phy-reset-pins node causes U-Boot to misbehave, can you check if this patch fixes it (there is a bug in the line "return msm_gpio_direction_input(dev, gpio);", it should become just "msm_gpio_direction_input(dev, gpio);").
I had the exact same issue with the gpio-regulator driver and this was the solution I ended up going with.
https://urldefense.com/v3/__https://lore.kernel.org/u-boot/20240131-b4-qcom-... [lore[.]kernel[.]org]
It is exactly this. With your patch I don't need to /delete-node/ anymore. I'll add a comment in the cover message that this series are depended on your patch.
Please can you split the power domain and clock patches into a separate series? As I'd like to depend on them for the next revision of my series, and we'd otherwise have a cyclical dependency.
Of course. As I understood, you are interested in "clk: qcom: clear div mask before assigning a new divider" and "clk: qcom: add support for power domains uclass", correct?
Yes.
Okay, I'll send it today.
I tried the power domain stuff out on SMD845 today and ran into quite a few issues. Specifically as a lot of the devices reference the rpmhpd power domain which we don't support (and don't *need* to support) in U-Boot. I'm not sure what the best way forward will be for this. Maybe a "nop" power domain driver?
Are you sure that they are not required?
"nop" power domain always is the option. Especially if it prints some warning about an unknown device. I had quite a lot of issues with clock and pin drivers that silently ignore unknown devices...
Do you have the same issues on sm8150?
Yes and no. No, because I was lucky so far and devices I tried to use in U-Boot does not require rpmhpd. Looking at DTS, I may only encounter issues with sdhc_2, which requires rpmhpd for some reason. Also UFS requires clock from rpmhcc.
And "yes", because I have found root cause for my troubles with UFS in Linux kernel, when I am skipping hyp.mbn. This is not strictly related to U-Boot, but you may be interested in this: apparently Qualcomm's hypervisor enables access to RPM (maybe brings it out of reset?). cmd-db shared memory region can't be accessed if I skip the hypervisor and try to boot directly into Linux. So now I am looking for ways to enable it.