If an ARM system has multiple cpus in the same socket and the
kernel is booted with maxcpus=1, secondary cpus are possible but
not present due to how platform_smp_prepare_cpus() is called.
Since most typical ARM processors don't actually support physical
hotplug, initialize the present map to be equal to the possible
map in generic ARM SMP code. Also, always call
platform_smp_prepare_cpus() as long as max_cpus is non-zero (0
means no SMP) to allow platform code to do any SMP setup.
After applying this patch it's possible to boot an ARM system
with maxcpus=1 on the command line and then hotplug in secondary
cpus via sysfs. This is more in line with how x86 does things.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: David Brown <davidb@codeaurora.org>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Enable TCM support on the RealView PB1176 - we have now taken
the precautions necessary to support even multi-board builds of
RealView systems with TCM enabled.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This allows platforms to specify the clcokevent name upon registration.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This allows platforms to specify the rate of the SP804 clocksource via
the clk subsystem. While ARM boards clock these at 1MHz, BCMRing also
has SP804 timers but are clocked at different rates.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This allows platforms to specify the clocksource name upon
registration, which is necessary should they wish to register more
than one sp804 clocksource.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rather than having each platform class provide a mach/smp.h header for
smp_cross_call(), arrange for them to register the function with the
core ARM SMP code instead.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The set_vpp() method provided by physmap passes a map_info back to
the platform code, which has little relevance as far as the platform
is concerned (this parameter is completely unused).
Instead, pass the platform_device, which can be used in the pismo
driver to retrieve some important information in a nicer way, instead
of the hack that was in place.
The empty set_vpp function in board-at572d940hf_ek.c is left untouched,
as the board/SoC is scheduled for removal.
Cc: Andrew Victor <linux@maxim.org.za>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Philipp Zabel <philipp.zabel@gmail.com>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Acked-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Acked-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested on a PB11-MPCore.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Since mandatory barriers may be used (explicitly or implicitly via readl
etc.) to ensure the ordering between Device and Normal memory accesses,
a DMB is not enough. This patch converts it to a DSB.
Cc: Colin Cross <ccross@android.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rather than each platform providing its own function to adjust the
zone sizes, use the new ARM_DMA_ZONE_SIZE definition to perform this
adjustment. This ensures that the actual DMA zone size and the
ISA_DMA_THRESHOLD/MAX_DMA_ADDRESS definitions are consistent with
each other, and moves this complexity out of the platform code.
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The values of ISA_DMA_THRESHOLD and MAX_DMA_ADDRESS are related; one is
the physical/bus address, the other is the virtual address. Both need
to be kept in step, so rather than having platforms define both, allow
them to define a single macro which sets both of these macros
appropraitely.
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The second GIC, present when EB board is used with a MPCore tile,
was initialised starting with irq number 64, which made interrupts
64-95 in the primary GIC unusable.
Signed-off-by: Pawel Moll <pawel.moll@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>
Realview and Versatile Express local timer support is identical, so
consolidate the implementations.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The AMBA DMA macro definitions are not used, and the AMBA Primecell DMA
support makes no use of them either, so they can be removed.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Initialize the clock tree and our sched_clock() early.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This switches Realview platforms to use the consolidated CLCD panel
support, including the display capabilities. As Realview uses a PL111,
it can support the full range of pixel formats - 444, 5551, 565 in both
RGB and BGR mode.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
As PHYS_OFFSET will be becoming a variable, we can't have it used in
initializers nor assembly code. Replace those in generic code with
a run-time initialization. Replace those in platform code using the
individual platform specific PLAT_PHYS_OFFSET.
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Acked-by: David Brown <davidb@codeaurora.org>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This uncouple PHYS_OFFSET from the platform definitions, thereby
facilitating run-time computation of the physical memory offset.
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Magnus Damm <damm@opensource.se>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Wan ZongShun <mcuos.com@gmail.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Acked-by: Jiandong Zheng <jdzheng@broadcom.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Make Realview EB ARM11MPCore and PB11MPCore select the new V6K CPU
option.
Tested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
As no one seems to really know which configuration options tie up with
which boards, I thought I'd do some investigation and try to work it
out. After discussion with some folk in linaro, I think I have this
nailed.
The names are updated to use the name on the front of the appropriate
board user guide for the various baseboards, which I've taken to be
the official name for each board.
I haven't significantly updated the descriptions for the tiles as that
is even less clear - as far as I can see on ARMs website, there is no
Cortex-A9 tile for Realview EB - only ARM11MPCore, ARM1156T2F-S,
ARM1176TZF-S and Cortex-R4F. So exactly what this 'Multicore Cortex-A9
Tile' is...
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>
Convert versatile platforms to use the new sched_clock() infrastructure
for extending 32bit counters to full 64-bit nanoseconds.
Tested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The original scheme for reporting spurious wakeups was broken - it
tried to use printk() from a context which wasn't coherent with the
other CPUs, which risks corrupting the printk() data.
Fix this by noting the number spurious wakeups, and only report them
when we are properly woken - when we will be coherent with the rest
of the system.
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>
With "ARM: CPU hotplug: remove bug checks in platform_cpu_die()", we
now do not use hard_smp_processor_id(), we no longer need to read the
hardware processor ID. Remove the include providing this function.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
platform_cpu_die() is entered from the CPU's own idle thread, which
can not be migrated to other CPUs. Moreover, the 'cpu' argument
comes from the thread info, which will always be the 'current'
CPU. So remove this useless bug check.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We always need to wait for the dying CPU to reach a safe state before
taking it down, irrespective of the requirements of the platform.
Move the completion code into the ARM SMP hotplug code rather than
having each platform re-implement this.
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>
Milo is an old boot loader, which is no longer relevant for these
platforms. References to it are misleading. Move the code out
of poke_milo(), and remove references to milo in comments.
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>
Ensure that the number of CPUs is sanity checked before setting
the number of possible CPUs. This avoids any chance of overflowing
the cpu_possible bitmap.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Provide a standard get_irqnr_preamble assembler macro for platforms
to use, which retrieves the base address of the GIC CPU interface
from gic_cpu_base_addr. Allow platforms to override this by defining
HAVE_GET_IRQNR_PREAMBLE.
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>
Every architecture using the GIC has a gic_cpu_base_addr pointer for
GIC 0 for their entry assembly code to use to decode the cause of the
current interrupt. Move this into the common GIC code.
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>
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>
Provide gic_init() which initializes the GIC distributor and current
CPU's GIC interface for the boot (or single) CPU.
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>
Use the GIC demux code in asm/hardware/entry-macro-gic.S
on the Realview subarchitecture.
Signed-off-by: Magnus Damm <damm@opensource.se>
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>
Russell King