BMC/Intel-BMC/linux.git/arch/arc/include/asm/smp.h, branch dev

ARC: Allow SMP kernel to build/boot on UP-only infrastructure

2014-09-27T09:19:01+00:00

In light of recent SNAFU with SMP build, allow simple platform to build as SMP but run UP. * Remove the dependence on simulation SMP extension to enable quick build/test iterations of SMP kernel. * In absence of platform SMP registration, prevent the NULL smp feature name from borkign the system Signed-off-by: Vineet Gupta

ARC: [SMP] IPI ACK interface doesn't need "self" cpu-id

2013-12-23T06:35:04+00:00

The interface is confusing, it feels like we are getting "sender" info, whereas it is the "receiver", which can very well be retrived by smp_processor_id(), if need be. Signed-off-by: Vineet Gupta

ARC: [SMP] cpumask not needed in IPI send path

2013-12-23T06:35:04+00:00

The current IPI sending callstack needlessly involves cpumask. arch_send_call_function_single_ipi(cpu) / smp_send_reschedule(cpu) ipi_send_msg(cpumask_of(cpu)) --> [cpu to cpumask] plat_smp_ops.ipi_send(callmap) for_each_cpu(callmap) --> [cpuask to cpu] do_plat_specific_ipi_PER_CPU Given that current backends are not capable of 1:N IPIs, lets simplify the interface for now, by keeping "a" cpu all along. Signed-off-by: Vineet Gupta

arc: remove '__init' for first_lines_of_secondary()

2013-11-06T05:11:43+00:00

first_lines_of_secondary() is a '__init' function, but it may be called by __cpu_up() by _cpu_up() by cpu_up() which is a normal export symbol function. So recommend to remove '__init'. The related warning (with allmodconfig): MODPOST vmlinux.o WARNING: vmlinux.o(.text+0x315c): Section mismatch in reference from the function __cpu_up() to the function .init.text:first_lines_of_secondary() The function __cpu_up() references the function __init first_lines_of_secondary(). This is often because __cpu_up lacks a __init annotation or the annotation of first_lines_of_secondary is wrong. Signed-off-by: Chen Gang

ARC: [Review] Multi-platform image #7: SMP common code to use callbacks

2013-02-15T17:46:16+00:00

This again is for switch from singleton platform SMP API to multi-platform paradigm Platform code is not yet setup to populate the callbacks, that happens in next commit Signed-off-by: Vineet Gupta Cc: Arnd Bergmann Acked-by: Arnd Bergmann

ARC: [Review] Multi-platform image #3: switch to board callback

2013-02-15T17:46:14+00:00

-platform API is retired and instead callbacks are used Signed-off-by: Vineet Gupta Cc: Arnd Bergmann Acked-by: Arnd Bergmann

ARC: SMP support

2013-02-15T17:46:02+00:00

ARC common code to enable a SMP system + ISS provided SMP extensions. ARC700 natively lacks SMP support, hence some of the core features are are only enabled if SoCs have the necessary h/w pixie-dust. This includes: -Inter Processor Interrupts (IPI) -Cache coherency -load-locked/store-conditional ... The low level exception handling would be completely broken in SMP because we don't have hardware assisted stack switching. Thus a fair bit of this code is repurposing the MMU_SCRATCH reg for event handler prologues to keep them re-entrant. Many thanks to Rajeshwar Ranga for his initial "major" contributions to SMP Port (back in 2008), and to Noam Camus and Gilad Ben-Yossef for help with resurrecting that in 3.2 kernel (2012). Note that this platform code is again singleton design pattern - so multiple SMP platforms won't build at the moment - this deficiency is addressed in subsequent patches within this series. Signed-off-by: Vineet Gupta Cc: Arnd Bergmann Cc: Thomas Gleixner Cc: Rajeshwar Ranga Cc: Noam Camus Cc: Gilad Ben-Yossef

ARC: Atomic/bitops/cmpxchg/barriers

2013-02-11T14:30:30+00:00

This covers the UP / SMP (with no hardware assist for atomic r-m-w) as well as ARC700 LLOCK/SCOND insns based. Signed-off-by: Vineet Gupta