with clk frequency setting code gone by prev commits, we can elide the
unconditonal DT parsing to the specific case of quad core config where
we possibly need to fudge the DT value.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
historically axs103 platform code used to set the cpu clk by writing to
PLL registers directly. however the axs10x clk driver is now upstream so
no need to do this amymore.
Driver is selected automatically when CONFIG_ARC_PLAT_AXS10X is set
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[vgupta: deleted more code not needed anymore]
Current implementation relies on L1 line length which might easily
be smaller than L2 line (which is usually the case BTW).
Imagine this typical case: L2 line is 128 bytes while L1 line is
64-bytes. Now we want to allocate small buffer and later use it for DMA
(consider IOC is not available).
kmalloc() allocates small KMALLOC_MIN_SIZE-sized, KMALLOC_MIN_SIZE-aligned
That way if buffer happens to be aligned to L1 line and not L2 line we'll be
flushing and invalidating extra portions of data from L2 which will cause
cache coherency issues.
And since KMALLOC_MIN_SIZE is bound to ARCH_DMA_MINALIGN the fix could
be simple - set ARCH_DMA_MINALIGN to the largest cache line we may ever
get. As of today neither L1 of ARC700 and ARC HS38 nor SLC might not be
longer than 128 bytes.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
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>
Preserve eflags and gpa1 aux during entry/exit into kernel as these
could be modified by kernel mode
These registers used by compare exchange instructions.
- GPA1 is used for compare value,
- EFLAGS got bit reflects atomic operation response.
EFLAGS is zeroed for each new user task so it won't get its
parent value.
Signed-off-by: Liav Rehana <liavr@mellanox.com>
Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
save EFLAGS, and GPA1 auxiliary registers during context switch,
since they may be changed by the new task in kernel mode, while using atomic
ops e.g. cmpxchg.
Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
HW bug description: in case of HW thread context switch
the dpc configuration of the exiting thread is dragged
one cycle into the next thread.
In order to avoid the consequences of this bug, the DPC register
is set to an initial value, and not changed afterwards.
Signed-off-by: Elad Kanfi <eladkan@mellanox.com>
Signed-off-by: Noam Camus <noamca@mellanox.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This commit add new configuration that enables us to distinguish
between building the kernel for platforms that have a different set
of auxiliary registers for each cpu and platforms that have a shared
set of auxiliary registers across every thread in each core.
On platforms that implement a different set of auxiliary registers
disabling this configuration insures that we initialize registers on
every cpu and not just for the first thread of the core.
Example for non shared registers is working with EZsim (non silicon)
Signed-off-by: Liav Rehana <liavr@mellanox.com>
Signed-off-by: Noam Camus <noamca@mellanox.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
We add ability for all cores at NPS SoC to control the number of cycles
HW thread can execute before it is replace with another eligible
HW thread within the same core. The replacement is done by the
HW scheduler.
Signed-off-by: Noam Camus <noamca@mellanox.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[vgupta: simplified handlign of out of range argument value]
Some of the boot printing code had printk() w/o explicit log level.
This patch introduces consistency allowing platforms to switch to less
verbose console logging using cmdline.
NPS400 with 4K CPUs needs to avoid the cpu info printing for faster
bootup.
Signed-off-by: Noam Camus <noamca@mellanox.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
On ARC700 (and nSIM), user mode memory error triggers an L2 interrupt
which is handled gracefully by kernel (or it tries to despite this being
imprecise, and error could get charged to kernel itself). The offending
task is killed and kernel moves on.
NPS hardware however raises a Machine Check exception for same error
which is NOT recoverable by kernel.
This patch aligns kernel handling for nSIM case, to same as hardware by
overriding the default user space bus error handler.
Signed-off-by: Noam Camus <noamca@mellanox.com>
Signed-off-by: Elad Kanfi <eladkan@mellanox.com>
[vgupta: rewrote changelog]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
When HW threads are active we want CPU to enter idle state only
for the calling HW thread and not to put on sleep all HW threads
sharing this core. For this need the NPS400 got dedicated instruction
so only calling thread is entring sleep and all other are still awake
and can execute instructions.
Signed-off-by: Noam Camus <noamca@mellanox.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[vgupta: reworked patch to not use inline ifdef but a new function itself]
This paves way for creating a 3rd variant needed for NPS ARC700 without
littering ifdey'ery all over the place
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This way when we execute "ex" during trying to hold lock we can switch to
other HW thread and utilize the core intead of just spinning on a lock.
We noticed about 10% improvement of execution time with hackbench test.
Signed-off-by: Noam Camus <noamca@mellanox.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This counter represents threshold for consecutive stall which
would trigger HW threads scheduling. However when enabled, low
threshhold values cause performance degradation and in the
worst case even livelock.
So disable it by resorting to HW reset value
Signed-off-by: Noam Camus <noamca@mellanox.com>
Reviewed-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[vgupta: fixed changelog]
Due to a HW bug in NPS400 we get from time to time false TLB miss.
Workaround this by validating each miss.
Signed-off-by: Noam Camus <noamca@mellanox.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>