On 2/7/19 6:19 PM, Oleksandr wrote:
[...]
+ /* Update registers with correct frequency */ + writel(freq, TIMER_BASE + TIMER_CNTFID0); + asm volatile("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq));
+ /* Make sure arch timer is started by setting bit 0 of CNTCR */ + writel(1, TIMER_BASE + TIMER_CNTCR);
Shouldn't this be in the timer driver instead ?
Which timer driver? Probably, I missed something, but I didn't find any arch timer driver being used for Gen2.
I see that TMU timer (arch/sh/lib/time.c) is used as a system timer, but it is yet another IP.
Would it be correct, if I move arch timer updating code to arch/arm/mach-rmobile directory?
Actually, at the same location the corresponding code lives in Linux:
https://elixir.bootlin.com/linux/v5.0-rc5/source/arch/arm/mach-shmobile/setu...
Presumably if this is something else than TMU, it needs proper driver that goes into drivers/ .
Did I get your point correctly that new driver (specially for Gen2 arch timer) should be introduced in U-Boot and
the only one thing it is intended to do is to configure that timer for the future use by Linux/Hypervisor?
If yes, the only question I have is how that new driver is going to be populated? There is no corresponding node for arch timer in the device tree.
https://elixir.bootlin.com/linux/v5.0-rc5/source/arch/arm/boot/dts/r8a7790.d...
So, do I need specially for this case add arch timer node with reg and compatible properties?
Sorry if I ask obvious questions, not familiar enough with U-Boot.
You would need a DT entry and a bit of code to start the timer in case the PSCI is enabled, yes. This would then fit into the DM/DT paradigm.
+ } +}
+/*
- In order not to break compilation if someone decides to build
with PSCI
- support disabled, keep these dummy functions.
- */
That's currently the only use-case.
Shall I drop this comment and dummy functions below?
Since there is no PSCI support, yes.
Understand.
[...]
I'd like to have a cover letter go with V2, which describes what you're trying to achieve here.
Yes, sure. Cover letter is present for the current V1 as well.
I thought that I had CC-ed all.
This is a link to it:
http://u-boot.10912.n7.nabble.com/PATCH-0-3-PSCI-support-for-r8a7790-SoC-Lag...
Thanks