Commit Graph

7 Commits

Author SHA1 Message Date
Eugeniy Paltsev f3205de98d ARC: mcip: update MCIP debug mask when the new cpu came online
As of today we use hardcoded MCIP debug mask, so if we launch
kernel via debugger and kick fever cores than HW has all cpus
hang at the momemt of setup MCIP debug mask.

So update MCIP debug mask when the new cpu came online, instead of
use hardcoded MCIP debug mask.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2018-02-28 10:45:31 -08:00
Eugeniy Paltsev 07423d00a2 ARC: mcip: halt GFRC counter when ARC cores halt
In SMP systems, GFRC is used for clocksource. However by default the
counter keeps running even when core is halted (say when debugging via a
JTAG debugger). This confuses Linux timekeeping and triggers flase RCU stall
splat such as below:

| [ARCLinux]# while true; do ./shm_open_23-1.run-test ; done
| Running with 1000 processes for 1000 objects
| hrtimer: interrupt took 485060 ns
|
| create_cnt: 1000
| Running with 1000 processes for 1000 objects
| [ARCLinux]# INFO: rcu_preempt self-detected stall on CPU
|       2-...: (1 GPs behind) idle=a01/1/0 softirq=135770/135773 fqs=0
| INFO: rcu_preempt detected stalls on CPUs/tasks:
| 	0-...: (1 GPs behind) idle=71e/0/0 softirq=135264/135264 fqs=0
|	2-...: (1 GPs behind) idle=a01/1/0 softirq=135770/135773 fqs=0
|	3-...: (1 GPs behind) idle=4e0/0/0 softirq=134304/134304 fqs=0
|	(detected by 1, t=13648 jiffies, g=31493, c=31492, q=1)

Starting from ARC HS v3.0 it's possible to tie GFRC to state of up-to 4
ARC cores with help of GFRC's CORE register where we set a mask for
cores which state we need to rely on.

We update cpu mask every time new cpu came online instead of using
hardcoded one or using mask generated from "possible_cpus" as we
want it set correctly even if we run kernel on HW which has fewer cores
than expected (or we launch kernel via debugger and kick fever cores
than HW has)

Note that GFRC halts when all cores have halted and thus relies on
programming of Inter-Core-dEbug register to halt all cores when one
halts.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[vgupta: rewrote changelog]
2018-02-28 10:45:31 -08:00
Yuriy Kolerov 6f0310a126 ARCv2: IDU-intc: Use build registers for getting numbers of interrupts
This enhancement is needed to allow masking all available common interrupts
in IDU interrupt controller in boot time since the kernel can
discover a number of them from the build register. Also now there
is no need to specify in device tree a list of used core interrupts
by IDU. E.g. before:

    idu_intc: idu-interrupt-controller {
        compatible = "snps,archs-idu-intc";
        interrupt-controller;
        interrupt-parent = <&core_intc>;
        #interrupt-cells = <2>;
        interrupts = <24 25 26 27 28 29 30 31>;
    };

and after:

    idu_intc: idu-interrupt-controller {
        compatible = "snps,archs-idu-intc";
        interrupt-controller;
        interrupt-parent = <&core_intc>;
        #interrupt-cells = <2>;
    };

Signed-off-by: Yuriy Kolerov <yuriy.kolerov@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2017-02-06 09:37:57 -08:00
Vineet Gupta 517e7610d2 ARCv2: MCIP: update the BCR per current changes
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2017-01-24 11:05:59 -08:00
Vineet Gupta b26c2e3823 ARC: breakout timer include code into separate header ...
... which allows for use in drivers/clocksource later

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-11-30 11:54:25 -08:00
Vineet Gupta 2d7f5c48c0 ARC: move mcip.h into include/soc and adjust the includes
Also remove the dependency on ARCv2, to increase compile coverage for
!ARCV2 builds

Acked-by: Daniel Lezcano <daniel.lezcnao@linaro.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-11-30 11:54:25 -08:00
Vineet Gupta c33a605dd6 ARC: breakout aux handling into a separate header
ARC timers use aux registers for programming and this paves way for
moving ARC timer drivers into drivers/clocksource

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-11-30 11:54:25 -08:00