Rework of SMTC support to make it work with the new clock event system,
allowing "tickless" operation, and to make it compatible with the use of
the "wait_irqoff" idle loop. The new clocking scheme means that the
previously optional IPI instant replay mechanism is now required, and has
been made more robust.
Signed-off-by: Kevin D. Kissell <kevink@paralogos.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Though from a hardware perspective it would be sensible to use only a
32-bit unsigned int type Linux defines interrupt flags to be stored in
an unsigned long and nothing else.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This converts mips to use the new helpers for smp_call_function() and
friends, and adds support for smp_call_function_single(). Not tested,
but it compiles.
mips shares the same IPI for smp_call_function() and
smp_call_function_single(), since not all mips platforms have enough
available IPIs to support seperate setups.
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
It is not being used by Malta and shouldn't be needed for MIPSsim.
Signed-off-by: Chris Dearman <chris@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Modify the SMTC initialization code to allow boot-time specification not
only of how many VPEs and TCs to use, but also how many TCs out of the
allowed pool are to be bound to VPE 0. The new boot option is "vpe0tcs=N",
where N is an integer. Using it in combination with the existing options
allows arbitrary assignments across the 2 VPEs of a 34K. e.g. "maxtcs=3
vpe0tcs=1" forces VPE0 to have 1 TC, while VPE1 has 2, and "maxtcs=4
vpe0tcs=3" forces VPE0 to have 3 TCs, while VPE1 gets 1. If no vpe0tcs
option is specified, the traditional algorithm of evenly dividing TCs
between available VPEs, with the odd "slop" going to VPE0, is retained.
The reason for doing this is to allow a finer balancing of TCs which can
handle I/O interrupts on Malta (those on VPE 0) and those which cannot.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The kernel currently only supports broadcasting of the timer interrupt
from a single timer, not multicasting into two multicast groups of
processors. So the implemented mechanism for SMTC works by broadcasting
the cp0 compare interrupt on VPE 0 and ignoring it on any additional VPEs.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
For some platforms it's definitions may conflict. So that's the one-liner.
The rest is 10 square kilometers of collateral damage fixup this include
used to paper over.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Recently a few direct accesses to the thread_info in the task structure snuck
back, so this wraps them with the appropriate wrapper.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
local_irq_restore -> raw_local_irq_restore -> irq_restore_epilog ->
smtc_ipi_replay -> smtc_ipi_dq -> spin_unlock_irqrestore ->
_spin_unlock_irqrestore -> local_irq_restore
The recursion does abort when there is no more IPI queued for a CPU, so
this isn't usually fatal which is why we got away with this for so long
until this was discovered by code inspection.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Make smtc_setup_irq() update the list of interrupts which need to be
watched by the debug code itself. Also there is no need to initialize the
IPI swint when running with a single VPE, so don't initialize it.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The irq_base for {mips,rm7k,rm9k}_cpu_irq_init() are constant on all
platforms and are same value on most platforms (0 or 16, depends on
CONFIG_I8259). Define them in asm-mips/mach-generic/irq.h and make
them customizable. This will save a few cycle on each CPU interrupt.
A good side effect is removing some dependencies to MALTA in generic
SMTC code.
Although MIPS_CPU_IRQ_BASE is customizable, this patch changes irq
mappings on DDB5477, EMMA2RH and MIPS_SIM, since really customizing
them might cause some header dependency problem and there seems no
good reason to customize it. So currently only VR41XX is using custom
MIPS_CPU_IRQ_BASE value, which is 0 regardless of CONFIG_I8259.
Testing this patch on those platforms is greatly appreciated. Thank
you.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
SMTC pseudo-interrupts between TCs are deferred and queued if the target
TC is interrupt-inhibited (IXMT). In the first SMTC prototypes, these
queued IPIs were serviced on return to user mode, or on entry into the
kernel idle loop. The INSTANT_REPLAY option dispatches them as part of
local_irq_restore() processing, which adds runtime overhead (hence the
option to turn it off), but ensures that IPIs are handled promptly even
under heavy I/O interrupt load.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Further incorporation of generic irq framework. Replacing __do_IRQ()
by proper flow handler would make the irq handling path a bit simpler
and faster.
* use generic_handle_irq() instead of __do_IRQ().
* use handle_level_irq for obvious level-type irq chips.
* use handle_percpu_irq for irqs marked as IRQ_PER_CPU.
* setup .eoi routine for irq chips possibly used with handle_percpu_irq.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Use the new IRQF_ constants and remove the SA_INTERRUPT define
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
locking init cleanups:
- convert " = SPIN_LOCK_UNLOCKED" to spin_lock_init() or DEFINE_SPINLOCK()
- convert rwlocks in a similar manner
this patch was generated automatically.
Motivation:
- cleanliness
- lockdep needs control of lock initialization, which the open-coded
variants do not give
- it's also useful for -rt and for lock debugging in general
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
