linux-toradex.git/arch/arc/kernel, branch v4.9.90

ARC: Re-enable MMU upon Machine Check exception

2017-09-27T12:39:23+00:00

commit 1ee55a8f7f6b7ca4c0c59e0b4b4e3584a085c2d3 upstream.

I recently came upon a scenario where I would get a double fault
machine check exception tiriggered by a kernel module.
However the ensuing crash stacktrace (ksym lookup) was not working
correctly.

Turns out that machine check auto-disables MMU while modules are allocated
in kernel vaddr spapce.

This patch re-enables the MMU before start printing the stacktrace
making stacktracing of modules work upon a fatal exception.

Signed-off-by: Jose Abreu 
Reviewed-by: Alexey Brodkin 
Signed-off-by: Vineet Gupta 
[vgupta: moved code into low level handler to avoid in 2 places]
Signed-off-by: Greg Kroah-Hartman

ARCv2: IRQ: Call entry/exit functions for chained handlers in MCIP

2017-08-07T01:59:49+00:00

[ Upstream commit e51d5d02f688c45b6f644f472f0c80fdfa73f0cb ]

It is necessary to call entry/exit functions for parent interrupt
controllers for proper masking/unmasking of interrupt lines.

Signed-off-by: Yuriy Kolerov 
Signed-off-by: Vineet Gupta 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ARCv2: smp-boot: wake_flag polling by non-Masters needs to be uncached

2017-06-17T04:41:57+00:00

[ Upstream commit 78f824d4312a8944f5340c6b161bba3bf2c81096 ]

This is needed on HS38 cores, for setting up IO-Coherency aperture properly

The polling could perturb the caches and coherecy fabric which could be
wrong in the small window when Master is setting up IOC aperture etc
in arc_cache_init()

We do it only for ARCv2 based builds to not affect EZChip ARCompact
based platform.

Signed-off-by: Vineet Gupta 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ARC: smp-boot: Decouple Non masters waiting API from jump to entry point

2017-06-17T04:41:57+00:00

[ Upstream commit bf02454a741b58682a82c314a9a46bed930ed2f7 ]

For run-on-reset SMP configs, non master cores call a routine which
waits until Master gives it a "go" signal (currently using a shared
mem flag). The same routine then jumps off the well known entry point of
all non Master cores i.e. @first_lines_of_secondary

This patch moves out the last part into one single place in early boot
code.

This is better in terms of absraction (the wait API only waits) and
returns, leaving out the "jump off to" part.

In actual implementation this requires some restructuring of the early
boot code as well as Master now jumps to BSS setup explicitly,
vs. falling thru into it before.

Technically this patch doesn't cause any functional change, it just
moves the ugly #ifdef'ry from assembly code to "C"

Signed-off-by: Vineet Gupta 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ARC: [arcompact] brown paper bag bug in unaligned access delay slot fixup

2017-02-14T23:25:33+00:00

commit a524c218bc94c705886a0e0fedeee45d1931da32 upstream.

Reported-by: Jo-Philipp Wich 
Fixes: 9aed02feae57bf7 ("ARC: [arcompact] handle unaligned access delay slot")
Cc: linux-kernel@vger.kernel.org
Cc: linux-snps-arc@lists.infradead.org
Signed-off-by: Vineet Gupta 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ARC: [arcompact] handle unaligned access delay slot corner case

2017-02-01T07:33:08+00:00

commit 9aed02feae57bf7a40cb04ea0e3017cb7a998db4 upstream.

After emulating an unaligned access in delay slot of a branch, we
pretend as the delay slot never happened - so return back to actual
branch target (or next PC if branch was not taken).

Curently we did this by handling STATUS32.DE, we also need to clear the
BTA.T bit, which is disregarded when returning from original misaligned
exception, but could cause weirdness if it took the interrupt return
path (in case interrupt was acive too)

One ARC700 customer ran into this when enabling unaligned access fixup
for kernel mode accesses as well

Signed-off-by: Vineet Gupta 
Signed-off-by: Greg Kroah-Hartman

ARC: module: Fix !CONFIG_ARC_DW2_UNWIND builds

2017-01-26T07:24:37+00:00

commit eb1357d942e5d96de6b4c20a8ffa55acf96233a2 upstream.

commit d65283f7b695b5 added mod->arch.secstr under
CONFIG_ARC_DW2_UNWIND, but used it unconditionally which broke builds
when the option was disabled. Fix that by adjusting the #ifdef guard.

And while at it add a missing guard (for unwinder) in module.c as well

Reported-by: Waldemar Brodkorb 
Fixes: d65283f7b695b5 ("ARC: module: elide loop to save reference to .eh_frame")
Tested-by: Anton Kolesov 
Reviewed-by: Alexey Brodkin 
[abrodkin: provided fixlet to Kconfig per failure in allnoconfig build]
Signed-off-by: Vineet Gupta 
Signed-off-by: Greg Kroah-Hartman

ARCv2: MCIP: Use IDU_M_DISTRI_DEST mode if there is only 1 destination core

2016-11-08T20:22:52+00:00

ARC linux uses 2 distribution modes for common interrupts: round robin
mode (IDU_M_DISTRI_RR) and a simple destination mode (IDU_M_DISTRI_DEST).
The first one is used when more than 1 cores may handle a common interrupt
and the second one is used when only 1 core may handle a common interrupt.

However idu_irq_set_affinity() always sets IDU_M_DISTRI_RR for all affinity
values. But there is no sense in setting of such mode if only 1 core must
handle a common interrupt.

Signed-off-by: Yuriy Kolerov 
Signed-off-by: Vineet Gupta

ARC: IRQ: Do not use hwirq as virq and vice versa

2016-11-08T20:05:10+00:00

This came up when reviewing code to address missing IRQ affinity
setting in AXS103 platform and/or implementing hierarchical IRQ domains

- smp_ipi_irq_setup() callers pass hwirq but in turn calls
  request_percpu_irq() which expects a linux virq. So invoke
  irq_find_mapping() to do the conversion
  (also explicitify this in code by renaming the args appropriately)

- idu_of_init()/idu_cascade_isr() were similarly using linux virq where
  hwirq is expected, so do the conversion using irqd_to_hwirq() helper

Signed-off-by: Yuriy Kolerov 
[vgupta: made changelog a bit concise a bit]
Signed-off-by: Vineet Gupta

ARC: [plat-eznps] set default baud for early console

2016-11-08T17:39:37+00:00

For CONFIG_SERIAL_EARLYCON we need 800MHz for NPS SoC
The early console driver uses BASE_BAUD and not using dtb.

The default of 50MHz is NOT good for NPS SoC.

Signed-off-by: Noam Camus 
Signed-off-by: Vineet Gupta