Re: [PATCH 14/19] arm64: dts: exynos: Add dts files for 64-bit Exynos5433 SoC

From: Chanwoo Choi
Date: Tue Dec 02 2014 - 10:47:58 EST


Dear Mark,

On Tue, Dec 2, 2014 at 9:13 PM, Mark Rutland <mark.rutland@xxxxxxx> wrote:
> Hi,
>
>> >> + psci {
>> >> + compatible = "arm,psci";
>> >> + method = "smc";
>> >> + cpu_off = <0x84000002>;
>> >> + cpu_on = <0xC4000003>;
>> >> + };
>> >
>> > Given your comments on the latest posting, has CPU_OFF been tested, and
>> > does it work for _all_ CPUs (including CPU0)?
>>
>> At current version,
>> CPU_OFF of Exynos5433 is not working. I'm now working to find the cause of CPU_OFF fail.
>> (I got CPU_ON of Exynos5433 all cores.)
>
> CPU_OFF should not be described in the DT unless it works.

OK, I'll drop 'cpu_off" property on next patchset. After fixing it,
I'll re-send separate patch.

>
> [...]
>
>> >> + soc: soc {
>> >> + compatible = "simple-bus";
>> >> + #address-cells = <1>;
>> >> + #size-cells = <1>;
>> >> + ranges;
>> >
>> > Is that valid when changing the number of cells? The address spaces
>> > aren't strictly identical in that case, and I'd expect a translation
>> > something like:
>> >
>> > ranges = <0x0 0x0 0x0 0xff000000>;
>>
>> I'll fix it after checking correct spec.
>
> Thanks.
>
> [...]
>
>> >> + gic:interrupt-controller@11001000 {
>> >> + compatible = "arm,gic-400";
>> >> + #interrupt-cells = <3>;
>> >> + interrupt-controller;
>> >> + reg = <0x11001000 0x1000>,
>> >> + <0x11002000 0x1000>,
>> >> + <0x11004000 0x2000>,
>> >> + <0x11006000 0x2000>;
>> >> + interrupts = <1 9 0xf04>;
>> >> + };
>> >
>> > The GICC needs to be 0x2000 long to map the GICC_DIR, which is at
>> > 0x1000-0x1003.
>>
>> Do you mean that following dt node is right for gic-400?
>>
>> reg = <0x11001000 0x1000>,
>> <0x11002000 0x2000>, <- I changed the the range of GICC.
>> <0x11004000 0x2000>,
>> <0x11006000 0x2000>;
>
> Yes.

OK. I'll fix it.

>
> [...]
>
>> >> + pinctrl_alive: pinctrl@10580000 {
>> >> + compatible = "samsung,exynos5433-pinctrl";
>> >> + reg = <0x10580000 0x1000>;
>> >> +
>> >> + wakeup-interrupt-controller {
>> >> + compatible = "samsung,exynos7-wakeup-eint";
>> >> + interrupts = <0 16 0>;
>> >> + };
>> >> + };
>> >
>> > How exactly does the wakeup interrupt controller interact with the GIC?
>> > Surely the relationship between the two should be described?
>>
>> The pinctrl_alive contains the alive part of GPIO PAD (gpa0~gpa3).
>>
>> The each GPA0/GPA1 of pinctrl_alive pad did map to unique SPI number of GIC
>> amd GPA2/GPA3 use only one interrupt (SPI[16]) as following:
>>
>> +&pinctrl_alive {
>> + gpa0: gpa0 {
>> + gpio-controller;
>> + #gpio-cells = <2>;
>> +
>> + interrupt-controller;
>> + interrupt-parent = <&gic>;
>> + interrupts = <0 0 0>, <0 1 0>, <0 2 0>, <0 3 0>,
>> + <0 4 0>, <0 5 0>, <0 6 0>, <0 7 0>;
>> + #interrupt-cells = <2>;
>> + };
>> +
>> + gpa1: gpa1 {
>> + gpio-controller;
>> + #gpio-cells = <2>;
>> +
>> + interrupt-controller;
>> + interrupt-parent = <&gic>;
>> + interrupts = <0 8 0>, <0 9 0>, <0 10 0>, <0 11 0>,
>> + <0 12 0>, <0 13 0>, <0 14 0>, <0 15 0>;
>> + #interrupt-cells = <2>;
>> + };
>>
>> gpa0-0 - SPI[0]
>> gpa0-1 - SPI[1]
>> gpa0-2 - SPI[2]
>> gpa0-3 - SPI[3]
>> gpa0-4 - SPI[4]
>> gpa0-5 - SPI[5]
>> gpa0-6 - SPI[6]
>> gpa0-7 - SPI[7]
>>
>> gpa1-0 - SPI[8]
>> gpa1-1 - SPI[9]
>> gpa1-2 - SPI[10]
>> gpa1-3 - SPI[11]
>> gpa1-4 - SPI[12]
>> gpa1-5 - SPI[13]
>> gpa1-6 - SPI[14]
>> gpa1-7 - SPI[15]
>>
>> GPA2/GPA3 use only one interrupt (SPI[16]).
>>
>> The pinctrl-exynos.c driver initialized external wakeup interrupt
>> (e.g., GPA0/GPA1/GPA2/GPA3 of Exynos5433) in exynos_eint_wkup_init() function.
>>
>> Following patch[1] adds the control for Exynos5433 wakeup irq.The exynos5433_pin_ctrl structure
>> includes '.eint_wkup_init = exynos_eint_wkup_init;' fields to handle wakeup interrupt of Exynos SoC.
>>
>> [PATCHv2] pinctrl: exynos: Add support for Exynos543
>> - https://lkml.org/lkml/2014/12/2/207
>>
>> +struct samsung_pin_ctrl exynos5433_pin_ctrl[] = {
>> + {
>> + /* pin-controller instance 0 data */
>> + .pin_banks = exynos5433_pin_banks0,
>> + .nr_banks = ARRAY_SIZE(exynos5433_pin_banks0),
>> + .eint_wkup_init = exynos_eint_wkup_init,
>> + .suspend = exynos_pinctrl_suspend,
>> + .resume = exynos_pinctrl_resume,
>> + .label = "exynos5433-gpio-ctrl0",
>> + }, {
>>
>> And,
>> 'struct exynos_irq_chip exynos7_wkup_irq_chip' handles the external interrupt of Exynos5433 SoC
>> because Exynos5433 is the same with Exynos7 EINT (External Interrupt) register offset.
>>
>> We can check it following patch[1] to control wakeup interrupt for Exynos7/Exynos5433.
>> - [1] [patch] pinctrl: exynos: Add irq_chip instance for Exynos7 wakeup interrupts
>> https://git.kernel.org/cgit/linux/kernel/git/linusw/linux-pinctrl.git/commit/?h=for-next&id=14c255d35b25126149fb2fd199b030404229af65
>>
>>
>> +static struct exynos_irq_chip exynos7_wkup_irq_chip __initdata = {
>> + .chip = {
>> + .name = "exynos7_wkup_irq_chip",
>> + .irq_unmask = exynos_irq_unmask,
>> + .irq_mask = exynos_irq_mask,
>> + .irq_ack = exynos_irq_ack,
>> + .irq_set_type = exynos_irq_set_type,
>> + .irq_set_wake = exynos_wkup_irq_set_wake,
>> + .irq_request_resources = exynos_irq_request_resources,
>> + .irq_release_resources = exynos_irq_release_resources,
>> + },
>> + .eint_con = EXYNOS7_WKUP_ECON_OFFSET,
>> + .eint_mask = EXYNOS7_WKUP_EMASK_OFFSET,
>> + .eint_pend = EXYNOS7_WKUP_EPEND_OFFSET,
>> +};
>>
>> If happen external interrupt by pressing power button, the ops of 'struct exynos_irq_chip exynos7_wkup_irq_chip'
>> would handle the interrupt.
>>
>> For exampl, If I use following GPAx as interrupt, I can check it on the result of /proc/interrupts.
>> gpa2-7 - power key
>> gpa2-0 - volume-up key
>> gpa2-1 - volume-up key
>> gpa0-7 - s2mps13 pmic irq
>>
>> 'exynos7_wkup_irq_chip' would handle the external interrupt(gpa).
>>
>> #cat /proc/interrupts
>> 1: 0 0 0 0 0 0 0 exynos7_wkup_irq_chip 0 volume-up key
>> 2: 0 0 0 0 0 0 0 exynos7_wkup_irq_chip 1 volume-down key
>> 7: 0 0 0 0 0 0 0 exynos7_wkup_irq_chip 7 s2mps13
>> 8: 0 0 0 0 0 0 0 exynos7_wkup_irq_chip 7 power key
>>
>>
>> IMHO,
>> Happen SPI -> GIC -> Cortex-A57/Cortex-A53 -> pinctrl-exynos.c -> exynos7_wkup_irq_chip -> irq handling
>
> So physically interrupts are fed into the wakeup IRQ chip, which routes
> them to the GIC? And we describe such in DT, as opposed to pretending
> interrupts are fed straight into the GIC, and bolting the wakeup
> controller on the side?

GIC is well working with pinctrl-exynos.c for Exynos SoC in mainline kernel.
Do you want to know the detailed relation between GIC and
pinctrl-exynos driver or not?
If I misunderstand, please let me know your question again.

Best Regards,
Chanwoo Choi
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/