Convert both Realview and VExpress to use struct smp_operations to
provide their SMP and CPU hotplug operation.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Scan flatten device looking for A5/A9 SCU node and initialize
it using base address in "reg" property. If nothing is found,
assume that there is no special SCU initialization required
and initialize CPUs basing on numbers of "cpu" type devices
in "cpus" node of the Device Tree.
All this happens only if the board was booted with FDT,
otherwise ct_desc callbacks are used.
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
This patch gets rid of the MMIO_P2V and __MMIO_P2V macros,
defining constant virtual base for motherboard and tile
peripherals instead.
Additionally, in preparation for the new motherboard memory
map, the motherboard peripherals are using base pointers
calculated in runtime, instead of compile-time calculated
values.
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Once the ENDPROC is in place, BSYM() in not longer necessary
to get correct pointer to versatile_secondary_startup().
Tested-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Acked-by: Dave Martin <dave.martin@linaro.org>
The current Versatile Express BSP defines the MACHINE_START macro
in the core tile code.
This patch moves this into the generic board code and introduces a
method for determining the current tile at runtime, allowing the
Kernel to have support for multiple tiles compiled in. Tile-specific
functions are executed via a descriptor struct containing the correct
implementations for the current tile.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Realview and Versatile Express share the same SMP bringup code, so
consolidate the two implementations.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fix two section mismatch warnings in the platform SMP bringup code for
Realview and Versatile Express:
WARNING: arch/arm/mach-realview/built-in.o(.text+0x8ac): Section mismatch in reference from the function write_pen_release() to the variable .cpuinit.data:pen_release
The function write_pen_release() references
the variable __cpuinitdata pen_release.
This is often because write_pen_release lacks a __cpuinitdata
annotation or the annotation of pen_release is wrong.
WARNING: arch/arm/mach-vexpress/built-in.o(.text+0x7b4): Section mismatch in reference from the function write_pen_release() to the variable .cpuinit.data:pen_release
The function write_pen_release() references
the variable __cpuinitdata pen_release.
This is often because write_pen_release lacks a __cpuinitdata
annotation or the annotation of pen_release is wrong.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
There is a subtle race in the CPU hotplug code, where a CPU which has
been offlined can online itself before being requested, which results
in things going astray on the next online/offline cycle.
What happens in the normal online/offline/online cycle is:
CPU0 CPU3
requests boot of CPU3
pen_release = 3
flush cache line
checks pen_release, reads 3
starts boot
pen_release = -1
... requests CPU3 offline ...
... dies ...
checks pen_release, reads -1
requests boot of CPU3
pen_release = 3
flush cache line
checks pen_release, reads 3
starts boot
pen_release = -1
However, as the write of -1 of pen_release is not fully flushed back to
memory, and the checking of pen_release is done with caches disabled,
this allows CPU3 the opportunity to read the old value of pen_release:
CPU0 CPU3
requests boot of CPU3
pen_release = 3
flush cache line
checks pen_release, reads 3
starts boot
pen_release = -1
... requests CPU3 offline ...
... dies ...
checks pen_release, reads 3
starts boot
pen_release = -1
requests boot of CPU3
pen_release = 3
flush cache line
Fix this by grouping the write of pen_release along with its cache line
flushing code to ensure that any update to pen_release is always pushed
out to physical memory.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
All platforms call trace_hardirqs_off() in their secondary startup code,
so move this into the core SMP code - it doesn't need to be in the
per-platform code.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
There is a certain amount of smp_prepare_cpus() which doesn't belong
in the platform support code - that is, code which is invariant to the
SMP implementation. Move this code into arch/arm/kernel/smp.c, and
add a platform_ prefix to the original function.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
scu_get_core_count() never returns zero cores, so we don't need to
check and correct if ncores is zero.
Tegra was missing the check against NR_CPUS, leading to a potential
bitfield overflow if this becomes the case.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We don't need to re-pass the base address for the CPU interfaces to the
GIC for secondary CPUs, as it will never be different from the boot CPU
- and even if it was, we'd overwrite the boot CPU's base address.
Get rid of this argument, and rename to gic_secondary_init().
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This allows us to use smp_cross_call() to trigger a number of different
software generated interrupts, rather than combining them all on one
SGI. Recover the SGI number via do_IPI.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
