Consolidating the "pen_release" stuff amongst the various SoC
implementations gives credence to having a CPU holding pen for
secondary CPUs. However, this is far from the truth.
Many SoC implementations cargo-cult copied various bits of the pen
release implementation from the initial Realview/Versatile Express
implementation without understanding what it was or why it existed.
The reason it existed is because these are _development_ platforms,
and some board firmware is unable to individually control the
startup of secondary CPUs. Moreover, they do not have a way to
power down or reset secondary CPUs for hot-unplug. Hence, the
pen_release implementation was designed for ARM Ltd's development
platforms to provide a working implementation, even though it is
very far from what is required.
It was decided a while back to reduce the duplication by consolidating
the "pen_release" variable, but this only made the situation worse -
we have ended up with several implementations that read this variable
but do not write it - again, showing the cargo-cult mentality at work,
lack of proper review of new code, and in some cases a lack of testing.
While it would be preferable to remove pen_release entirely from the
kernel, this is not possible without help from the SoC maintainers,
which seems to be lacking. However, I want to remove pen_release from
arch code to remove the credence that having it gives.
This patch removes pen_release from the arch code entirely, adding
private per-SoC definitions for it instead, and explicitly stating
that write_pen_release() is cargo-cult copied and should not be
copied any further. Rename write_pen_release() in a similar fashion
as well.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Remove the majority of cache flushing calls from the individual platform
files. This is now handled by the core code.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The code in arch/arm/mach-prima2/headsmp.S is used for
both boot time initialization and for cpu hotplug,
so it must not be discarded after the initial boot
is complete. This replaces the __INIT annotation
with __CPUINIT, and marks the sirfsoc_cpu_die as
__ref to annotate that it correctly uses the sections.
Without this patch, building prima2_defconfig results in:
WARNING: arch/arm/mach-prima2/built-in.o(.cpuinit.text+0x130): Section mismatch in reference from the function sirfsoc_boot_secondary() to the function .init.text:sirfsoc_secondary_startup()
The function __cpuinit sirfsoc_boot_secondary() references
a function __init sirfsoc_secondary_startup().
If sirfsoc_secondary_startup is only used by sirfsoc_boot_secondary then
annotate sirfsoc_secondary_startup with a matching annotation.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Barry Song <baohua.song@csr.com>
this patch adds tick timer, smp entries and generic DT machine
for SiRFmarco dual-core SMP chips.
with the added marco, we change the defconfig, using the same
defconfig, we get a zImage which can work on both prima2 and
marco.
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Cc: Mark Rutland <mark.rutland@arm.com>
