linux-toradex.git/arch/sparc/kernel/sun4d_irq.c, branch v3.2.11

Add support for allocating irqs for bootbus devices

2011-06-07T23:06:33+00:00

Some devices that can generate interrupts are connected directly to the
CPU through the bootbus on sun4d. This patch allows IRQs to be allocated
for such devices. The information used for allocating interrupts for
sbus devices are present at the corresponding SBI node. For bootbus
devices this information is present in the bootbus node.

Signed-off-by: Kjetil Oftedal 
Signed-off-by: David S. Miller

Do not skip interrupt sources in sun4d interrupt handler and acknowledge interrupts correctly

2011-06-07T23:06:33+00:00

During the introduction of genirq on sparc32 bugs were introduced in
the interrupt handler for sun4d. The interrupts handler checks the status
of the various sbus interfaces in the system and generates a virtual
interrupt, based upon the location of the interrupt source. This lookup
was broken by restructuring the code in such a way that index and shift
operations were performed prior to comparing this against the values
read from the interrupt controllers.

This could cause the handler to loop eternally as the interrupt source
could be skipped before any check was performed. Additionally
sun4d_encode_irq performs shifting internally, so it should not be performed
twice.

In sun4d_unmask interrupts were not correctly acknowledged, as the
corresponding bit it the interrupt mask was not actually cleared.

Signed-off-by: Kjetil Oftedal 
Signed-off-by: David S. Miller

Restructure sun4d_build_device_irq so that timer interrupts can be allocated

2011-06-07T23:06:32+00:00

sun4d_build_device_irq was called without a valid platform_device when
the system timer was initialized on sun4d systems. This caused a NULL
pointer crash.

Josip Rodin suggested that the current sun4d_build_device_irq should be
split into two functions. So that the timer initialization could skip
the slot and sbus interface detection code in sun4d_build_device_irq, as
this does not make sence due to the timer interrupts not being generated
from a device located on sbus.

Signed-off-by: Kjetil Oftedal 
Signed-off-by: David S. Miller

sparc32, sun4d: Implemented SMP IPIs support for SUN4D machines

2011-05-16T20:07:44+00:00

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: Daniel Hellstrom 
Signed-off-by: David S. Miller

sparc32: always define boot_cpu_id

2011-04-21T23:44:44+00:00

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: Daniel Hellstrom 
Signed-off-by: David S. Miller

sparc32: genirq support

2011-04-20T05:11:40+00:00

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  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: Sam Ravnborg 
Acked-by: Daniel Hellstrom 
Tested-by: Daniel Hellstrom 
Tested-by: Marcel van Nies 
Cc: Thomas Gleixner 
Signed-off-by: David S. Miller

sparc32,sun4d: rename sbus_tid to board_to_cpu in irq support

2011-04-20T05:11:39+00:00

The new name reflects the actual usage much better.

Signed-off-by: Sam Ravnborg 
Signed-off-by: David S. Miller

sparc32: introduce build_device_irq

2011-03-17T01:19:14+00:00

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: Sam Ravnborg 
Signed-off-by: David S. Miller

sparc32: introduce sparc_irq_config

2011-03-17T01:19:13+00:00

sparc_irq_config is used to hold the platform specific irq setup.

Signed-off-by: Sam Ravnborg 
Signed-off-by: David S. Miller

sparc32, sun4d: add comment in empty statement in sun4d_request_irq()

2011-03-17T01:19:11+00:00

This looked like a bug to me.
Add a comment so next reader is hopefully less confused.

Signed-off-by: Sam Ravnborg 
Signed-off-by: David S. Miller