Commit Graph

109832 Commits

Author SHA1 Message Date
Benjamin Herrenschmidt
fa6428ebfa Merge commit 'jwb/jwb-next' 2008-10-07 11:15:07 +11:00
Victor Gallardo
3d5fa877bd powerpc/44x: Add AMCC Arches defconfig file
Add a defconfig for the AMCC Arches evaluation board

Signed-off-by: Victor Gallardo <vgallardo@amcc.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-10-02 13:08:49 -04:00
Victor Gallardo
e9ee2924dd powerpc/44x: Add AMCC Arches DTS
Basic functionality for the AMCC Arches eval Board.

Signed-off-by: Victor Gallardo <vgallardo@amcc.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-10-02 13:08:14 -04:00
Victor Gallardo
e00de30a9d powerpc/44x: Add AMCC Arches eval board support
The Arches Evaluation board is based on the AMCC 460GT SoC chip.
This board is a dual processor board with each processor providing
independent resources for Rapid IO, Gigabit Ethernet, and serial
communications.  Each 460GT has it's own 512MB DDR2 memory, 32MB NOR FLASH,
UART, EEPROM and temperature sensor, along with a shared debug port.
The two 460GT's will communicate with each other via shared memory,
Gigabit Ethernet and x1 PCI-Express.

Signed-off-by: Victor Gallardo <vgallardo@amcc.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-10-02 13:08:02 -04:00
Victor Gallardo
9e3cb29497 ibm_newemac: Add support for GPCS, SGMII and M88E1112 PHY
Add support for the phy types found on the Arches and other
PowerPC 460 based boards.

Signed-off-by: Victor Gallardo <vgallardo@amcc.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-10-02 13:06:42 -04:00
Matthias Fuchs
5a013fc7bb powerpc/4xx: Allow 4xx PCI bridge to be disabled via device tree
This patch allows the 4xx (conventional) PCI bridge to be disabled
via the device tree. This is needed for 4xx PCI adapter hardware.

Use the PCI node's status property to disable the PCI bridge.

Signed-off-by: Matthias Fuchs <matthias.fuchs@esd-electronics.com>
Acked-by: Stefan Roese <sr@denx.de>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-10-02 11:59:01 -04:00
Benjamin Herrenschmidt
c9b59da130 Merge commit 'kumar/kumar-mmu' 2008-10-02 16:11:49 +10:00
Benjamin Herrenschmidt
9f5494b797 Merge commit 'kumar/kumar-dma' 2008-10-02 16:11:44 +10:00
Kumar Gala
d2b194ed82 powerpc/math-emu: Use kernel generic math-emu code
The math emulation code is centered around a set of generic macros that
provide the core of the emulation that are shared by the various
architectures and other projects (like glibc).  Each arch implements its
own sfp-machine.h to specific various arch specific details.

For historic reasons that are now lost the powerpc math-emu code had
its own version of the common headers.  This moves us to using the
kernel generic version and thus getting fixes when those are updated.

Also cleaned up exception/error reporting from the FP emulation functions.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-10-01 08:40:07 -05:00
Josh Boyer
fbcc4bacee ibm_newemac: MAL support for PowerPC 405EZ
The PowerPC 405EZ SoC has some differences in the interrupt layout and
handling for the MAL.  The SERR, TXDE, and RXDE interrupts are OR'd into
a single interrupt.  Also, due to the possibility for interrupt coalescing,
the TXEOB and RXEOB interrupts require an interrupt bit to be cleared in
the ICINTSTAT SDR.

This sets the proper MAL feature bits for 405EZ boards, and adds a common
shared handler for SERR, TXDE, and RXDE.  The defines for the ICINTSTAT DCR
are added to the proper header file as well.

This has been adapted from code originally written by Stefan Roese.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-09-30 09:23:15 -04:00
Josh Boyer
ec4f9945b5 ibm_newemac: Introduce mal_has_feature
There are some PowerPC SoCs that do odd things with the MAL handling.  In
order to accommodate them, we need to introduce a feature mechanism that is
similar to the existing emac_has_feature function.

This adds a feature variable to the mal_instance structure, and adds a
mal_has_feature function.  Two features are defined and are guarded
by Kconfig options that are selected by the affected platforms.

MAL_FTR_CLEAR_ICINSTAT is used for platforms that need to clear the
interrupt bits in the ICINTSTAT SDR for txeob/rxeob.  This is common
on MAL implementations that have interrupt coalescing.

MAL_FTR_COMMON_ERR_INT is used for platforms that have SERR, TXDE,
and RXDE OR'd into a single interrupt bit.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-09-30 09:23:04 -04:00
Josh Boyer
b68d185ab1 ibm_newemac: Allow the "no flow control" EMAC feature to work
Some PowerPC 40x chips have errata that force us not to use the integrated
flow control.  We have the feature defined, but it currently can't be used
because it is never added to EMAC_FTRS_POSSIBLE.

This adds a Kconfig option for affected platforms to select and puts the
feature in the EMAC_FTRS_POSSIBLE list.  This is set for PowerPC 405EZ
platforms as well.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-09-30 09:22:45 -04:00
Martyn Welch
a969e76a71 powerpc: Correct USB support for GE Fanuc SBC610
Support for the SBC610 VPX Single Board Computer from GE Fanuc (PowerPC
MPC8641D).

Fixup to correctly reconfigure USB, provided by an NEC uPD720101, after
device is reset. This requires a set of chip specific registers in the
devices configuration space to be correctly written, enabling all ports
and switching the device to use an external 48-MHz Oscillator.

Signed-off-by: Martyn Welch <martyn.welch@gefanuc.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-29 09:25:47 -05:00
Becky Bruce
0161dca52d powerpc: Drop redundant machine type print in show_cpuinfo
For many of the embedded boards, "model" and "Machine" are printing
the same thing; remove the redundant code and allow the generic
show_cpuinfo to print the model information.

Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Acked-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Martyn Welch <martyn.welch@gefanuc.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-29 09:23:06 -05:00
Anton Vorontsov
20d38e01d4 powerpc/fsl_soc: remove mpc83xx_wdt code
mpc83xx_wdt is the OF driver now, so we don't need fsl_soc constructor.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-29 09:22:45 -05:00
Kumar Gala
8d1fb8cbaa serial/mpc52xx_uart: remove code associated with !CONFIG_PPC_MERGE
Now that arch/ppc is gone we don't need CONFIG_PPC_MERGE anymore
remove the dead code associated with !CONFIG_PPC_MERGE.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-25 10:28:26 -05:00
Becky Bruce
4ee7084eb1 POWERPC: Allow 32-bit hashed pgtable code to support 36-bit physical
This rearranges a bit of code, and adds support for
36-bit physical addressing for configs that use a
hashed page table.  The 36b physical support is not
enabled by default on any config - it must be
explicitly enabled via the config system.

This patch *only* expands the page table code to accomodate
large physical addresses on 32-bit systems and enables the
PHYS_64BIT config option for 86xx.  It does *not*
allow you to boot a board with more than about 3.5GB of
RAM - for that, SWIOTLB support is also required (and
coming soon).

Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-24 16:29:44 -05:00
Kumar Gala
9a62c05180 powerpc/mm: Implement _PAGE_SPECIAL & pte_special() for 32-bit
Implement _PAGE_SPECIAL and pte_special() for 32-bit powerpc. This bit will
be used by the fast get_user_pages() to differenciate PTEs that correspond
to a valid struct page from special mappings that don't such as IO mappings
obtained via io_remap_pfn_ranges().

We currently only implement this on sub-arch that support SMP or will so
in the future (6xx, 44x, FSL-BookE) and not (8xx, 40x).

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-09-24 16:29:42 -05:00
Kumar Gala
9bf2b5cdc5 powerpc: Fixes for CONFIG_PTE_64BIT for SMP support
There are some minor issues with support 64-bit PTEs on a 32-bit processor
when dealing with SMP.

* We need to order the stores in set_pte_at to make sure the flag word
  is set second.
* Change pte_clear to use pte_update so only the flag word is cleared
* Added a WARN_ON to set_pte_at to ensure the pte isn't present for
  the 64-bit pte/SMP case (to ensure our assumption of this fact).

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Becky Bruce <becky.bruce@freescale.com>
2008-09-24 16:29:41 -05:00
Kumar Gala
0ba3418b8b powerpc: Introduce local (non-broadcast) forms of tlb invalidates
Introduced a new set of low level tlb invalidate functions that do not
broadcast invalidates on the bus:

_tlbil_all - invalidate all
_tlbil_pid - invalidate based on process id (or mm context)
_tlbil_va  - invalidate based on virtual address (ea + pid)

On non-SMP configs _tlbil_all should be functionally equivalent to _tlbia and
_tlbil_va should be functionally equivalent to _tlbie.

The intent of this change is to handle SMP based invalidates via IPIs instead
of broadcasts as the mechanism scales better for larger number of cores.

On e500 (fsl-booke mmu) based cores move to using MMUCSR for invalidate alls
and tlbsx/tlbwe for invalidate virtual address.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-24 16:29:40 -05:00
Becky Bruce
b9579689ad powerpc: Make dma_addr_t a u64 if CONFIG_PHYS_64BIT is set
Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-24 16:26:45 -05:00
Becky Bruce
4fc665b88a powerpc: Merge 32 and 64-bit dma code
We essentially adopt the 64-bit dma code, with some changes to support
32-bit systems, including HIGHMEM.  dma functions on 32-bit are now
invoked via accessor functions which call the correct op for a device based
on archdata dma_ops.  If there is no archdata dma_ops, this defaults
to dma_direct_ops.

In addition, the dma_map/unmap_page functions are added to dma_ops
because we can't just fall back on map/unmap_single when HIGHMEM is
enabled. In the case of dma_direct_*, we stop using map/unmap_single
and just use the page version - this saves a lot of ugly
ifdeffing.  We leave map/unmap_single in the dma_ops definition,
though, because they are needed by the iommu code, which does not
implement map/unmap_page.  Ideally, going forward, we will completely
eliminate map/unmap_single and just have map/unmap_page, if it's
workable for 64-bit.

Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-24 16:26:45 -05:00
Becky Bruce
8fae035324 powerpc: Drop archdata numa_node
Use the struct device's numa_node instead; use accessor functions
to get/set numa_node.

Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-24 16:26:43 -05:00
Becky Bruce
8dd0e95206 powerpc: Move iommu dma ops from dma.c to dma-iommu.c
32-bit platforms are about to start using dma.c; move the iommu
dma ops into their own file to make this a bit cleaner.

Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-24 16:26:42 -05:00
Becky Bruce
7c05d7e08d powerpc: Rename dma_64.c to dma.c
This is in preparation for the merge of the 32 and 64-bit
dma code in arch/powerpc.

Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-24 16:26:41 -05:00
Kumar Gala
782f04fc0c powerpc: Move 8xxx GPIO Kconfig under the platform menu
The initial patch had the option at the top level which wasn't
quite right.  Moving under the platform options is a bit better.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-23 23:36:32 -05:00
Kumar Gala
ee1130197e powerpc/86xx: Introduce a generic mpc86xx_defconfig
Introduced a mpc86xx_defconfig that enables all 86xx boards and moved
all other 86xx related defconfigs under configs/86xx to match 83xx
and 85xx.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-23 23:32:32 -05:00
Kumar Gala
aeb42762b8 powerpc/83xx: Add missing cell-index to dma-channel device nodes
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-23 22:05:10 -05:00
Kumar Gala
68e1ee62f0 powerpc: convert CONFIG_PPC_MERGE to CONFIG_PPC for legacy io checks
Now that arch/ppc is dead CONFIG_PPC_MERGE is always defined for all
powerpc platforms and we want to get rid of CONFIG_PPC_MERGE use
CONFIG_PPC instead.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-23 10:41:28 -05:00
Peter Korsgaard
1e16dfc1ba powerpc: gpio driver for mpc8349/8572/8610 and compatible
Structured similar to the existing QE GPIO support.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Acked-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-23 10:41:16 -05:00
Paul Mackerras
1afb7f809b Merge branch 'powerpc-next' of master.kernel.org:/pub/scm/linux/kernel/git/galak/powerpc 2008-09-21 18:18:21 -05:00
Paul Mackerras
ff4be78bb7 Merge branch 'next' of ssh://master.kernel.org/pub/scm/linux/kernel/git/jwboyer/powerpc-4xx 2008-09-21 18:17:25 -05:00
Becky Bruce
8b05cefca7 cpm_uart: Pass actual dev ptr to dma_* in ucc and cpm_uart serial
We're currently passing NULL, and really shouldn't be.

Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Acked-By: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-19 13:34:04 -05:00
Kumar Gala
b38fd42ff4 powerpc/fsl-booke: Fixup 64-bit PTE reading for SMP support
We need to create a false data dependency to ensure the loads of
the pte are done in the right order.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-19 13:31:04 -05:00
Kumar Gala
33a7f12274 powerpc: Fix build warnings introduced by PMC support on 32-bit
arch/powerpc/kernel/sysfs.c:197:7: warning: "CONFIG_6xx" is not defined
arch/powerpc/kernel/sysfs.c:141: warning: 'run_on_cpu' defined but not used

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-18 17:57:50 -05:00
Timur Tabi
c2fe59444e powerpc: add SSI-to-DMA properties to Freescale MPC8610 HPCD device tree
Add the fsl,playback-dma and fsl,capture-dma properties to the Freescale
MPC8610 HPCD device tree.  These properties connect the SSI nodes to the
DMA nodes for the DMA channels that the SSI should use.  Also update the
ssi.txt documentation.

These properties will be needed when the ASoC V2 version of the Freescale
MPC8610 device drivers are merged into the mainline.

Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-17 15:01:20 -05:00
Jochen Friedrich
f1eaf16a9e powerpc/cpm1: Fix race condition in CPM1 GPIO library.
The CPM1 GPIO library code uses the non thread-safe clrbits32/setbits32
macros. This patch protects them with a spinlock.

Based on the CPM2 patch from Laurent Pinchart <laurentp@cse-semaphore.com>,
commit 639d64456e.

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-16 13:43:24 -05:00
Martyn Welch
1a9314a0f6 powerpc: Default configuration for GE Fanuc SBC610
Support for the SBC610 VPX Single Board Computer from GE Fanuc (PowerPC
MPC8641D).

This is the default config file for GE Fanuc's SBC610, a 6U single board
computer, based on Freescale's MPC8641D.

Signed-off-by: Martyn Welch <martyn.welch@gefanuc.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-16 10:17:25 -05:00
Martyn Welch
54508214cf powerpc: Board support for GE Fanuc SBC610
Support for the SBC610 VPX Single Board Computer from GE Fanuc (PowerPC
MPC8641D).

This is the basic board support for GE Fanuc's SBC610, a 6U single board
computer, based on Freescale's MPC8641D.

Signed-off-by: Martyn Welch <martyn.welch@gefanuc.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-16 10:17:14 -05:00
Paul Gortmaker
66576a87dd powerpc/sbc8560: fix compile warning on CPM pin array
This is just a parallel of a5dc66e2ab
applied to the sbc8560 board.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-16 10:01:52 -05:00
Kumar Gala
48d6c64311 math-emu: Add support for reporting exact invalid exception
Some architectures (like powerpc) provide status information on the exact
type of invalid exception.  This is pretty straight forward as we already
report invalid exceptions via FP_SET_EXCEPTION.

We add new flags (FP_EX_INVALID_*) the architecture code can define if it
wants the exact invalid exception reported.

We had to split out the INF/INF and 0/0 cases for divide to allow reporting
the two invalid forms properly.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: David S. Miller <davem@davemloft.net>
2008-09-16 10:01:37 -05:00
Kumar Gala
40d3057ac0 math-emu: Fix compiler warnings
Fix warnings of the form:
arch/powerpc/math-emu/fsubs.c:15: warning: 'R_f1' may be used uninitialized in this function
arch/powerpc/math-emu/fsubs.c:15: warning: 'R_f0' may be used uninitialized in this function

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-16 10:01:37 -05:00
Becky Bruce
82331ab15f powerpc/85xx: fix build warning, remove silly cast
This fixes a build warning when PHYS_64BIT is enabled, and removes an
unnecessary cast to phys_addr_t (the variable being cast is already
a phys_addr_t)

Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-16 10:01:35 -05:00
Anton Vorontsov
307db95882 powerpc/83xx: mpc836x_mds: add support for the nor flash
This patch adds the localbus node, moves the bcsr node into the
localbus node, and adds the flash node.

Also enable MTD support in the defconfig.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-16 10:01:34 -05:00
Kumar Gala
7cfc4e5e7f serial/cpm_uart: Remove dead Kconfig options
With the change to device tree based setup we no longer need the explicit
Kconfig options for each SCC{1,4} or SMC{1,2} port.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-16 10:01:33 -05:00
Heiko Schocher
637166337c powerpc: Add support for mpc8247 based board MGCOGE from keymile.
Signed-off-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-16 10:01:32 -05:00
Heiko Schocher
e14d4af0c8 powerpc: Add support for the MPC852 based mgsuvd board from keymile.
Supported SMC1 (serial console), SCC3 Ethernet (10Mbps hdx).

Signed-off-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-16 10:01:30 -05:00
Martin Langer
a501d8f30e powerpc: Fix major revision number for Freescale cores
Some 74xx cores by Freescale are using the configuration field instead
of the major revision field for their revision number.  This corrects
the wrong behaviour for those ppc cores including my one.

There is a reference document at Freecale.  It describes the PVR
register.  This is based on that pdf.  You can find the document at:

http://www.freescale.com/files/archives/doc/support_info/PPCPVR.pdf

Signed-off-by: Martin Langer <martin-langer@gmx.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-15 11:08:48 -07:00
David Gibson
0b26425ce1 powerpc: Clean up hugepage pagetable allocation for powerpc with 16G pages
There is a small bug in the handling of 16G hugepages recently added
to the kernel.  This doesn't cause a crash or other user-visible
problems, but it does mean that more levels of pagetable are allocated
than makes sense for 16G pages.  The hugepage pagetables for the 16G
pages are allocated much lower in the pagetable tree than they should
be, with the intervening levels allocated with full pmd and pud pages
which will only ever have one entry filled in.

This corrects this problem, at the same time cleaning up the handling
of which level 64k versus 16M hugepage pagetables are allocated at.
The new way of formatting the tests should be more robust against
changes in pagetable structure, or any newly added hugepage sizes.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-15 11:08:47 -07:00
Sebastien Dugue
150c6c8fec powerpc: Make the irq reverse mapping radix tree lockless
The radix trees used by interrupt controllers for their irq reverse
mapping (currently only the XICS found on pSeries) have a complex
locking scheme dating back to before the advent of the lockless radix
tree.

This takes advantage of the lockless radix tree and of the fact that
the items of the tree are pointers to a static array (irq_map)
elements which can never go under us to simplify the locking.

Concurrency between readers and writers is handled by the intrinsic
properties of the lockless radix tree.  Concurrency between writers is
handled with a global mutex.

Signed-off-by: Sebastien Dugue <sebastien.dugue@bull.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-15 11:08:45 -07:00