Commit Graph

17 Commits

Author SHA1 Message Date
Vineet Gupta
760884bcd3 ARCv2: support manual regfile save on interrupts
[ Upstream commit e494239a00 ]

There's a hardware bug which affects the HSDK platform, triggered by
micro-ops for auto-saving regfile on taken interrupt. The workaround is
to inhibit autosave.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-23 14:35:16 +01:00
Alexey Brodkin
e8206d2baa ARCv2: SMP: Mask only private-per-core IRQ lines on boot at core intc
Recent commit a8ec3ee861 "arc: Mask individual IRQ lines during core
INTC init" breaks interrupt handling on ARCv2 SMP systems.

That commit masked all interrupts at onset, as some controllers on some
boards (customer as well as internal), would assert interrutps early
before any handlers were installed.  For SMP systems, the masking was
done at each cpu's core-intc.  Later, when the IRQ was actually
requested, it was unmasked, but only on the requesting cpu.

For "common" interrupts, which were wired up from the 2nd level IDU
intc, this was as issue as they needed to be enabled on ALL the cpus
(given that IDU IRQs are by default served Round Robin across cpus)

So fix that by NOT masking "common" interrupts at core-intc, but instead
at the 2nd level IDU intc (latter already being done in idu_of_init())

Fixes: a8ec3ee861 ("arc: Mask individual IRQ lines during core INTC init")
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
[vgupta: reworked changelog, removed the extraneous idu_irq_mask_raw()]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-28 16:11:15 -07:00
Alexey Brodkin
a8ec3ee861 arc: Mask individual IRQ lines during core INTC init
ARC cores on reset have all interrupt lines of built-in INTC enabled.
Which means once we globally enable interrupts (very early on boot)
faulty hardware blocks may trigger an interrupt that Linux kernel
cannot handle yet as corresponding handler is not yet installed.

In that case system falls in "interrupt storm" and basically never
does anything useful except entering and exiting generic IRQ handling
code.

One real example of that kind of problematic hardware is DW GMAC which
also has interrupts enabled on reset and if Ethernet PHY informs GMAC
about link state, GMAC immediately reports that upstream to ARC core
and here we are.

Now with that change we mask all individual IRQ lines making entire
system more fool-proof.

[This patch was motivated by Adaptrum platform support]

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Eugeniy Paltsev <paltsev@synopsys.com>
Tested-by: Alexandru Gagniuc <alex.g@adaptrum.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2017-08-11 06:38:31 +05:30
Yuriy Kolerov
be568e78db ARCv2: intc: Set default priority for all core interrupts
After reset all interrupts in the core interrupt controller has
the highest priority P0. If the platform supports Fast IRQs and
has more than 1 banks of registers then CPU automatically switch
banks of registers when P0 interrupt comes.

The problem is that the kernel expects that by default switching
of banks is not used by all interrupts. It is necessary to set a
default nonzero priority for all available interrupts to avoid
undefined behaviour.

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
179cf194e6 ARCv2: intc: Use runtime value of irq count for setting up intc
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2017-02-06 09:37:57 -08:00
Vineet Gupta
fe7b109946 ARC: [intc-*]: confine NR_CPU_IRQS to intc code
And even this willl change in subsequent patches where we resort to
using run time info instead...

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2017-02-06 09:37:57 -08:00
Yuriy Kolerov
e98a7bf0b0 ARCv2: intc: Use ARC_REG_STATUS32 for addressing STATUS32 reg
It is better to use it instead of magic numbers.

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
Yuriy Kolerov
2163266c27 ARC: IRQ: Use hwirq instead of virq in mask/unmask
It is necessary to use hwirq instead of virq when you communicate
with an interrupt controller since there is no guaranty that virq
numbers match hwirq numbers.

Signed-off-by: Yuriy Kolerov <yuriy.kolerov@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2017-01-04 17:12:10 -08:00
Vineet Gupta
107177b14d ARCv2: intc: default all interrupts to priority 1
ARC HS Cores support configurable multiple interrupt priorities of upto
16 levels. In commit dec2b2849c ("ARCv2: intc: Allow interruption by
lowest priority interrupt") we switched to 15 which seems a bit
excessive given that there would be rare hardware implementing so many
preemption levels AND running Linux. It would seem that 2 levels will be
more common so switch to 1 as the default priority level. This will be
the "lower" priority level saving 0 for implementing NMI style support.

This scheme also works in systems with more than 2 prioity levels as
well.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-12-14 09:23:46 -08:00
Yuriy Kolerov
bc0c7ece61 ARCv2: intc: Use kflag if STATUS32.IE must be reset
In the end of "arc_init_IRQ" STATUS32.IE flag is going to be affected by
"flag" instruction but "flag" never touches IE flag on ARCv2. So "kflag"
instruction must be used instead of "flag".

Signed-off-by: Yuriy Kolerov <yuriy.kolerov@synopsys.com>
Cc: stable@vger.kernel.org #4.2+
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-09-30 14:48:24 -07:00
Vineet Gupta
d21beffb0b ARC: [intc-*] switch to linear domain
Now that we have Timers probed from DT, don't need legacy domain

This however requires mapping to be called explicitly for the IRQ which
still can't (and probably never) be probed from DT such as IPI and
SOFTIRQ

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09 09:32:30 +05:30
Vineet Gupta
1b0ccb8a4e ARC: [intc-*] Do a domain lookup in primary handler for hwirq -> linux virq
The primary interrupt handler arch_do_IRQ() was passing hwirq as linux
virq to core code. This was fragile and worked so far as we only had legacy/linear
domains.

This came out of a rant by Marc Zyngier.
http://lists.infradead.org/pipermail/linux-snps-arc/2015-December/000298.html

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09 09:32:30 +05:30
Vineet Gupta
dec2b2849c ARCv2: intc: Allow interruption by lowest priority interrupt
ARC HS Cores support configurable multiple interrupt priorities of upto
16 levels.

There is processor "interrupt preemption threshhold" in STATUS32.E[4:1]
And several places need to set this up:
1. seed value as kernel is booting
2. seed value for user space programs
3. Arg to SLEEP instruction in idle task (what interrupt prio can wake)
4. Per-IRQ line prioirty (i.e. what is the priority of interrupt
   raised by a peripheral or timer or perf counter...

Currently above sites use the highest priority 0. This can be potential
problem when multiple priorities are supported. e.g. user space could
only be interrupted by P0 interrupt, not others...
So turn this over and instead make default interruption level to be
the lowest priority possible 15. This should be fine even if there are
fewer priority levels configured (say two: P0 HIGH, P1 LOW)

This feature also effectively disables FIRQ feature if present in
hardware config. With old code, a P0 interrupt would be FIRQ, needing
special handling (ISR or Register Banks) which is NOT supported yet.
Now it not be P0 (P15 or whatever is lowest prio) so FIRQ is not
triggered.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-02-10 06:38:50 +05:30
Vineet Gupta
8eb0984bf4 ARCv2: intc: Fix random perf irq disabling in SMP setup
As part of fixing another perf issue, observed that after a perf run,
the interrupt got disabled on one/more cores.

Turns out that despite requesting perf irq as percpu, the flow handler
registered was not handle_percpu_irq()

Given that on ARCv2 cores, IRQs < 24 are always private to cpu, we
register the right handler at the very onset.

Before Fix

| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:    0      0      0       0  ARCv2 core Intc  20 ARC perf counters
|
| [ARCLinux]# perf record -c 20000 /sbin/hackbench
| Running with 10*40 (== 400) tasks.
|
| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:    0    522      8    51916  ARCv2 core Intc  20 ARC perf counters
|
| [ARCLinux]# perf record -c 20000 /sbin/hackbench
| Running with 10*40 (== 400) tasks.
|
| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:    0    522      8   104368  ARCv2 core Intc  20 ARC perf counters

After Fix

| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:    0      0      0       0  ARCv2 core Intc  20 ARC perf counters
|
| [ARCLinux]# perf record -c 20000 /sbin/hackbench
| Running with 10*40 (== 400) tasks.
|
| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:  64198  62012  62697  67803  ARCv2 core Intc  20 ARC perf counters
|
| [ARCLinux]# perf record -c 20000 /sbin/hackbench
| Running with 10*40 (== 400) tasks.
|
| [ARCLinux]# cat /proc/interrupts | grep perf
|  20: 126014 122792 123301 133654  ARCv2 core Intc  20 ARC perf counters

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: stable@vger.kernel.org #4.2+
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-12 16:03:41 +05:30
Joël Porquet
70d93d8941 arc:irqchip: prepare for drivers/irqchip/irqchip.h removal
The IRQCHIP_DECLARE macro migrated to 'include/linux/irqchip.h'.

See commit 91e20b5040
("irqchip: Move IRQCHIP_DECLARE macro to include/linux/irqchip.h").

This patch removes the inclusions of private header 'drivers/irqchip/irqchip.h'
and if necessary replaces them with inclusions of 'include/linux/irqchip.h'.

Signed-off-by: Joel Porquet <joel@porquet.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-07-09 17:36:32 +05:30
Vineet Gupta
82fea5a1bb ARCv2: SMP: Support ARConnect (MCIP) for Inter-Core-Interrupts et al
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-22 14:06:56 +05:30
Vineet Gupta
820970a5aa ARCv2: [intc] HS38 core interrupt controller
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-22 14:06:55 +05:30