The sun4d does not seem to have a distingstion between soft and hard
IRQs. When generating IPIs the generated IRQ looks like a hard IRQ,
this patch adds a "IPI check" in the sun4d irq trap handler at a
predefined IRQ number (SUN4D_IPI_IRQ). Before generating an IPI
a per-cpu memory structure is modified for the "IPI check" to
successfully detect a IPI request to a specific processor, the check
clears the IPI work requested.

All three IPIs (resched, single and cpu-mask) use the same IRQ
number.

The IPI IRQ should preferrably be on a separate IRQ and definitly
not shared with IRQ handlers requesting IRQ with IRQF_SHARED.
Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Implement the three IPIs (resched, single and cpu-mask) generation
and interrupt handler catch. The sun4m has 15 soft-IRQs and three
of them is used with this patch, the three IPIs was previously
implemented with the cross-call IRQ15 which does not work with
locking routines such as spinlocks because IRQ15 is NMI, it may
cause deadlock.

The IRQ trap handler code assumes (in the same spritit as the old
it seems) that hard interrupts will be generated until handled
(level), when a IRQ happens the IRQ pending register is checked
for pending soft-IRQs. When both hard and soft IRQ happens at the
same time only soft-IRQs are handled.

The old code implemented a soft-IRQ traphandler at IRQ14 which
called smp_reschedule_irq which in turn called set_need_resched.
It seems to be an old relic and is replaced with the interrupt
traphander exit code RESTORE_ALL, it calls schedule() when
appropriate.
Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch implements SMP IPIs on LEON using software generated
IRQs to signal between CPUs.

The IPI IRQ number is set by using the ipi_num property in the
device tree, or defaults to 13. LEON SMP systems should reserve
IRQ 13 (and IRQ 15) to Linux in order for the defaults to work.
Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current sparc32 SMP IPI generation is implemented the
cross call function. The cross call function uses IRQ15 the
NMI, this is has the effect that IPIs will interrupt IRQ
critical areas and hang the system. Typically on/after
spin_lock_irqsave calls can be aborted.

The cross call functionality must still exist to flush
cache/TLBS.

This patch provides CPU models a custom way to implement
generation of IPIs on the generic code's request. The
typical approach is to generate an IRQ for each IPI case.

After this patch each sparc32 SMP CPU model needs to
implement IPIs in order to function properly.
Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

* proper initialization of boot_cpu_id (no hardcoding to 0)
 * use boot_cpu_id index to address into the IRQ controller where
   appropriate

Each CPU has a separate set of IRQ controller registers, this
patch makes sure that the boot-cpu registers are used instead
of CPU0's.
Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Define boot_cpu_id in single-processor kernels as well. This is
to support architectures which can boot on other than CPU0.

Sam Ravnborg has written the cleanup parts by extracting
boot_cpu_id from smp_32.c into setup_32.c and cleaned up
sun4d_irq.c.

boot_cpu_id was initialized before BSS was cleared in
sun4c_continue_boot, instead boot_cpu_id is set to 0xff to
avoid BSS. If boot_cpu_id is untouched (0xff) by bootup code
it will be overwritten to 0. boot_cpu_id4 is automatically
calculated in common code.
Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Do not require user to add "-p" to boot arguments to see
early info printed to prom console.

This is similar to the sparc64 functionality - which was added with:
3c62a2d3 ("[SPARC64]: Always register
a PROM based early console.")
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We did a cpu_probe() call each time a CPU got online - which
only effect was to save latest CPU/FPU info for use by show_cpuinfo().
Use same setup as for sparc64 where we probe for this info during startup,
and only once.

This allowed us to annotate a few functions __init which again
fixed the following section mismatch warnings:

WARNING: vmlinux.o(.text+0x65f0): Section mismatch in reference from the function set_cpu_and_fpu() to the (unknown reference) .init.rodata:(unknown)
WARNING: vmlinux.o(.text+0x65f8): Section mismatch in reference from the function set_cpu_and_fpu() to the (unknown reference) .init.rodata:(unknown)
WARNING: vmlinux.o(.text+0x664c): Section mismatch in reference from the function set_cpu_and_fpu() to the variable .init.rodata:manufacturer_info
WARNING: vmlinux.o(.text+0x6650): Section mismatch in reference from the function set_cpu_and_fpu() to the variable .init.rodata:manufacturer_info
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We have all the cpu related info in cpu.c - so move
the remaining functions to support /proc/cpuinfo to this file.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A simple implementation of CPU affinity, the first CPU in
the affinity CPU mask always takes the IRQ.
Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Cleaned up leon_init_timers() by removing unnecessary double checking
and one indentation level. Changed LEON_IMASK to LEON_IMASK(cpu).
Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The extended IRQ controller gives the LEON 16 more IRQs.

The patch installs a custom handler for the exetended controller
IRQ, where a register is read and the "real" IRQ causing IRQ is
determined.
Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The LEON interrupt controller has one single mask register for all
IRQs per CPU, even though the genirq layer protects us from accessing
the same IRQ at the same time other IRQs share the same mask register
and may thus interfere. Some other IRQ controllers has a mask register
or similar per IRQ instead which makes spinlocks unncessary.
Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The conversion of sparc32 to genirq is based on original work done
by David S. Miller.
Daniel Hellstrom has helped in the conversion and implemented
the shutdowm functionality.
Marcel van Nies <morcles@gmail.com> has tested this on Sparc Station 20

Test status:
sun4c      - not tested
sun4m,pci  - not tested
sun4m,sbus - tested (Sparc Classic, Sparc Station 5, Sparc Station 20)
sun4d      - not tested
leon       - tested on various combinations of leon boards,
             including SMP variants

generic
   Introduce use of GENERIC_HARDIRQS and GENERIC_IRQ_SHOW
   Allocate 64 IRQs - which is enough even for SS2000
   Use a table of irq_bucket to maintain uses IRQs
      irq_bucket is also used to chain several irq's that
      must be called when the same intrrupt is asserted
   Use irq_link to link a interrupt source to the irq
   All plafforms must now supply their own build_device_irq method
   handler_irq rewriten to use generic irq support

floppy
   Read FLOPPY_IRQ from platform device
   Use generic request_irq to register the floppy interrupt
   Rewrote sparc_floppy_irq to use the generic irq support

pcic:
   Introduce irq_chip
   Store mask in chip_data for use in mask/unmask functions
   Add build_device_irq for pcic
   Use pcic_build_device_irq in pci_time_init
   allocate virtual irqs in pcic_fill_irq

sun4c:
   Introduce irq_chip
   Store mask in chip_data for use in mask/unmask functions
   Add build_device_irq for sun4c
   Use sun4c_build_device_irq in sun4c_init_timers

sun4m:
   Introduce irq_chip
   Introduce dedicated mask/unmask methods
   Introduce sun4m_handler_data that allow easy access to necessary
     data in the mask/unmask functions
   Add a helper method to enable profile_timer (used from smp)
   Added sun4m_build_device_irq
   Use sun4m_build_device_irq in sun4m_init_timers

   TODO:
      There is no replacement for smp_rotate that always scheduled
      next CPU as interrupt target upon an interrupt

sun4d:
   Introduce irq_chip
   Introduce dedicated mask/unmask methods
   Introduce sun4d_handler_data that allow easy access to
   necessary data in mask/unmask fuctions
   Rewrote sun4d_handler_irq to use generic irq support

   TODO:
      The original implmentation of enable/disable had:

          if (irq < NR_IRQS)
               return;

      The new implmentation does not distingush between SBUS and cpu
      interrupts.
      I am no sure what is right here. I assume we need to do
      something for the cpu interrupts.

      I have not succeeded booting my sun4d box (with or without this patch)
      and my understanding of this platfrom is limited.
      So I would be a bit suprised if this works.

leon:
   Introduce irq_chip
   Store mask in chip_data for use in mask/unmask functions
   Add build_device_irq for leon
   Use leon_build_device_irq in leon_init_timers
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Acked-by: NDaniel Hellstrom <daniel@gaisler.com>
Tested-by: NDaniel Hellstrom <daniel@gaisler.com>
Tested-by: NMarcel van Nies <morcles@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the ifdeffery to a header file to make the logic more
obvious where we decide between PCI or SBUS init
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The new name reflects the actual usage much better.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

We have to pass task_struct of previous process to function
schedule_tail(). Currently in ret_from_fork previous thread_info
is passed:

switch_to: mov %g6, %g3 /* previous thread_info in g6 */

ret_from_fork: call    schedule_tail
                mov    %g3, %o0 /* previous thread_info is passed */

void schedule_tail(struct task_struct *prev);
Signed-off-by: NTkhai Kirill <tkhai@yandex.ru>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix all of the problems spotted by CONFIG_DEBUG_SECTION_MISMATCH under
arch/sparc during a 64-bit defconfig build.

They fall into two categorites:

1) of_device_id is marked as __initdata, and we can never do this
   since these objects sit in the device core data structures way
   past boot.  So even if a driver will never be reloaded, we have
   to keep the device ID table around.

   Mark such cases const instead.

2) The bootmem alloc/free handling code in mdesc.c was not fully
   marked __init as it should be, thus generating a reference
   to free_bootmem_late() (which is __init) from non-__init code.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: sparclinux@vger.kernel.org

Scripted with coccinelle.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: sparclinux@vger.kernel.org

Use the proper wrapper functions.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: sparclinux@vger.kernel.org

Make use of the new features in genirq:

1) Set the chip flag IRCHIP_EOI_IF_HANDLED, which ensures in the
   core code that irq_eoi() is only called when the interrupt was
   handled. That removes the extra status check in the callback.

2) Use the preflow handler, which is called from the fasteoi core code
   before the device handler. That avoids another status check and the
   open coded handler redirection.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: sparclinux@vger.kernel.org

During the preparation for testing the recent changes made to the SUN4D
specific code in the kernel by Sam Ravnborg the following was discovered:

Since the removal of of_platform_bus_type (commit: eca39301 )
multiboard SUN4Ds have not been able to boot. The kernel crashes due to a
zero-pointer error encountered when registering multiple M48T59 RTCs
(There is one on each board).

A patch for the was previously submitted, but the problem was not a
serious at that time, as it would only generate warnings. Now the kernel
will crash and stop executing before the serial console has been started.
(Crash output can be viewed by using the -p boot flag)
Signed-off-by: NKjetil Oftedal <oftedal@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Grab the pre-computed resource and map using of_ioremap().
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Similarly to irq_of_parse_and_map(), find the platform_device
object and return the pre-computed resource.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

gas used to accept (and ignore?) .size directives which referred to
undefined symbols, as this does.  In binutils 2.21 these are treated
as errors.
Signed-off-by: NBen Hutchings <ben@decadent.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Most of the warnings emitted (we fail arch/sparc file
builds with -Werror) were legitimate but harmless, however
one case (n2_pcr_write) was a genuine bug.

Based almost entirely upon a patch by Sam Ravnborg.
Reported-by: NDennis Gilmore <dennis@ausil.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

entry.S access percpu + global data defined in
sun4m_irq.c - so move the types to irq.h.
This makes sparse happy and allow us to utilize
asm-offsets later.

Also updated a few comments in the sun4m_irq.c file.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

build_device_irq() is used to encapsulate the plaform
specific details when we build an irq.
For now the default is a simple 1:1 but sun4d differs.
This patch refactors functionality - but does not change
the existing functionality.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sparc_irq_config is used to hold the platform specific irq setup.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a few includes back required to build with floppy enabled
Fix declaration of trapbase_cpu* so it is now consistent
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This converts the sparc clocksources to use clocksource_register_hz/khz
Signed-off-by: NJohn Stultz <johnstul@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A recent patch to the x86 randomization code caused me to take
a quick look at what we do on sparc64, and in doing so I noticed
that we sometimes calculate a non-page-aligned randomization value
and stick it into mmap_base.

I also noticed that since I copied the logic over from PowerPC,
the powerpc code has tweaked the randomization ranges in ways that
would benefit us as well.

For one thing, we should allow up to at least 8MB of randomization
otherwise huge-page regions when HPAGE_SIZE is 4MB never randomize
at all.

And on the 64-bit side we were using up to 4GB.  Tone it down to
1GB as 4GB can result in a lot of address space wastage.

Finally, make sure all computations are unsigned.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>