Commit Graph

22778 Commits

Author SHA1 Message Date
Lennert Buytenhek 009b47dfc7 [ARM] mv78xx0: add defconfig
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:45:10 +02:00
Stanislav Samsonov 794d15b25d [ARM] add Marvell 78xx0 ARM SoC support
The Marvell Discovery Duo (MV78xx0) is a family of ARM SoCs featuring
(depending on the model) one or two Feroceon CPU cores with 512K of L2
cache and VFP coprocessors running at (depending on the model) between
800 MHz and 1.2 GHz, and features a DDR2 controller, two PCIe
interfaces that can each run either in x4 or quad x1 mode, three USB
2.0 interfaces, two 3Gb/s SATA II interfaces, a SPI interface, two
TWSI interfaces, a crypto accelerator, IDMA/XOR engines, a SPI
interface, four UARTs, and depending on the model, two or four gigabit
ethernet interfaces.

This patch adds basic support for the platform, and allows booting
on the MV78x00 development board, with functional UARTs, SATA, PCIe,
GigE and USB ports.

Signed-off-by: Stanislav Samsonov <samsonov@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:45:10 +02:00
Lennert Buytenhek a9311cfed2 [ARM] Orion: PCIe x4/x1 detection support
The Discovery Duo (MV78xx0) has two x4 PCIe ports which can either
be used in x4 mode or in quad x1 mode.  This patch adds an accessor
function to the generic plat-orion PCIe handling code to detect in
which of the two modes we're running (which is determined by strap
pins and/or configured by the bootloader).

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:45:09 +02:00
Lennert Buytenhek 0a17c7bc0b [ARM] Feroceon: 88fr571-vd support
Add support for the Feroceon 88fr571-vd CPU core as found in e.g.
the Marvell Discovery Duo family of ARM SoCs.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:45:08 +02:00
Saeed Bishara 9307f05c77 [ARM] Kirkwood: add defconfig
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:45:07 +02:00
Saeed Bishara 651c74c74b [ARM] add Marvell Kirkwood (88F6000) SoC support
The Marvell Kirkwood (88F6000) is a family of ARM SoCs based on a
Shiva CPU core, and features a DDR2 controller, a x1 PCIe interface,
a USB 2.0 interface, a SPI controller, a crypto accelerator, a TS
interface, and IDMA/XOR engines, and depending on the model, also
features one or two Gigabit Ethernet interfaces, two SATA II
interfaces, one or two TWSI interfaces, one or two UARTs, a
TDM/SLIC interface, a NAND controller, an I2S/SPDIF interface, and
an SDIO interface.

This patch adds supports for the Marvell DB-88F6281-BP Development
Board and the RD-88F6192-NAS and the RD-88F6281 Reference Designs,
enabling support for the PCIe interface, the USB interface, the
ethernet interfaces, the SATA interfaces, the TWSI interfaces, the
UARTs, and the NAND controller.

Signed-off-by: Saeed Bishara <saeed@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:45:06 +02:00
Lennert Buytenhek 9c2af6c57c [ARM] Feroceon: 88fr131 support
Add support for the Shiva 88fr131 CPU core as found in e.g. the
Marvell Kirkwood family of ARM SoCs.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:45:05 +02:00
Lennert Buytenhek 99c6dc117d [ARM] Feroceon: L2 cache support
This patch adds support for the unified Feroceon L2 cache controller
as found in e.g. the Marvell Kirkwood and Marvell Discovery Duo
families of ARM SoCs.

Note that:

- Page table walks are outer uncacheable on Kirkwood and Discovery
  Duo, since the ARMv5 spec provides no way to indicate outer
  cacheability of page table walks (specifying it in TTBR[4:3] is
  an ARMv6+ feature).

  This requires adding L2 cache clean instructions to
  proc-feroceon.S (dcache_clean_area(), set_pte()) as well as to
  tlbflush.h ({flush,clean}_pmd_entry()).  The latter case is handled
  by defining a new TLB type (TLB_FEROCEON) which is almost identical
  to the v4wbi one but provides a TLB_L2CLEAN_FR flag.

- The Feroceon L2 cache controller supports L2 range (i.e. 'clean L2
  range by MVA' and 'invalidate L2 range by MVA') operations, and this
  patch uses those range operations for all Linux outer cache
  operations, as they are faster than the regular per-line operations.

  L2 range operations are not interruptible on this hardware, which
  avoids potential livelock issues, but can be bad for interrupt
  latency, so there is a compile-time tunable (MAX_RANGE_SIZE) which
  allows you to select the maximum range size to operate on at once.
  (Valid range is between one cache line and one 4KiB page, and must
  be a multiple of the line size.)

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:45:04 +02:00
Stanislav Samsonov 836a8051d5 [ARM] Feroceon: L1 cache range operation support
This patch adds support for the L1 D cache range operations that
are supported by the Marvell Discovery Duo and Marvell Kirkwood
ARM SoCs.

Signed-off-by: Stanislav Samsonov <samsonov@marvell.com>
Acked-by: Saeed Bishara <saeed@marvell.com>
Reviewed-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:45:03 +02:00
Lennert Buytenhek 7ea217a85e [ARM] Loki: add defconfig
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:45:02 +02:00
Lennert Buytenhek 777f9bebad [ARM] add Marvell Loki (88RC8480) SoC support
The Marvell Loki (88RC8480) is an ARM SoC based on a Feroceon CPU
core running at between 400 MHz and 1.0 GHz, and features a 64 bit
DDR controller, 512K of internal SRAM, two x4 PCI-Express ports,
two Gigabit Ethernet ports, two 4x SAS/SATA controllers, two UARTs,
two TWSI controllers, and IDMA/XOR engines.

This patch adds support for the Marvell LB88RC8480 Development
Board, enabling the use of the PCIe interfaces, the ethernet
interfaces, the TWSI interfaces and the UARTs.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:45:02 +02:00
Ke Wei 1219715de7 [ARM] Orion: add a separate BRIDGE_INT_TIMER1_CLR define
Some Feroceon-based SoCs have an MBUS bridge interrupt controller
that requires writing a one instead of a zero to clear edge
interrupt sources such as timer expiry.

This patch adds a new BRIDGE_INT_TIMER1_CLR define, which platform
code can set to either ~BRIDGE_INT_TIMER1 (write-zero-to-clear) or
BRIDGE_INT_TIMER1 (write-one-to-clear) depending on the platform.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:45:01 +02:00
Ke Wei ab6d15d506 [ARM] Feroceon: allow more old Feroceon IDs
There are a couple more Feroceon-based SoCs out in the field that use
different Variant and Architecture fields in their Main ID registers
-- this patch tweaks the processor match/mask in proc-feroceon.S to
catch those SoCs as well.

Signed-off-by: Ke Wei <kewei@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:45:00 +02:00
Nicolas Pitre 2e2023fe02 [ARM] Feroceon: catch other Feroceon CPU IDs in head.S
Tweak the Feroceon match/mask in arch/arm/boot/compressed/head.S to
match a couple of newer Feroceon cores (such as the 88fr571vd with
CPU ID 0x56155710, and the 88fr131 with CPU ID 0x56251310) as well.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:59 +02:00
Nicolas Pitre 6c386e58aa [ARM] Feroceon: speed up flushing of the entire cache
Flushing the L1 D cache with a test/clean/invalidate loop is very
easy in software, but it is not the quickest way of doing it, as
there is a lot of overhead involved in re-scanning the cache from
the beginning every time we hit a dirty line.

This patch makes proc-feroceon.S use "clean+invalidate by set/way"
loops according to possible cache configuration of Feroceon CPUs
(either direct-mapped or 4-way set associative).

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:58 +02:00
Lennert Buytenhek 79e90dd5aa [ARM] Orion: nuke orion5x_{read,write}
Nuke the Orion-specific orion5x_{read,write} wrappers.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:57 +02:00
Sylver Bruneau 7ec753ccc1 [ARM] Orion: add Maxtor Shared Storage II support
This patch adds support for the Maxtor Shared Storage II hardware.

Signed-off-by: Sylver Bruneau <sylver.bruneau@googlemail.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:55 +02:00
Alexander Clouter 7171d8672b [ARM] Orion: add Technologic Systems TS-78xx support
Signed-off-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:54 +02:00
Sylver Bruneau 530c854aa3 [ARM] Orion: remove code duplication in TS209 and TS409 setup files
Signed-off-by: Sylver Bruneau <sylver.bruneau@googlemail.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:54 +02:00
Martin Michlmayr b08d5af396 [ARM] Orion: add HP Media Vault mv2120 support
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:53 +02:00
Lennert Buytenhek 42452b77a1 [ARM] Orion: add Linksys WRT350N v2 support
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Tested-by: Dirk Teurlings <dirk@upexia.nl>
Tested-by: Peter van Valderen <p.v.valderen@gmail.com>
2008-06-22 22:44:52 +02:00
Lennert Buytenhek d2b2a6bbc0 [ARM] Orion: add 88F5181L (Orion-VoIP) support
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22 22:44:51 +02:00
Sylver Bruneau 47e9cffde6 [ARM] Orion: add QNAP TS-409 support
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:50 +02:00
Sylver Bruneau a0087f2fcf [ARM] Orion: implement power-off method for Kurobox Pro
This patch implements the communication with the microcontroller on the
Kurobox Pro and Linkstation Pro/Live boards.  This is allowing to send
the commands needed to power-off the board correctly.

Signed-off-by: Sylver Bruneau <sylver.bruneau@googlemail.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:49 +02:00
Lennert Buytenhek 2850a03773 [ARM] Orion: avoid setting ->force_phy_addr
The mv643xx_eth platform data field ->force_phy_addr only needs
to be set if the passed-in ->phy_addr field is zero (to distinguish
the case of not having specified a phy address
(force_phy_addr = 0) from the case where a phy address of zero needs
to be used (force_phy_addr = 1.))

Also, the ->force_phy_addr field will hopefully disappear in a
future mv643xx_eth reorganisation.

Therefore, this patch deletes the ->force_phy_addr field initialiser
from all Orion board code.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:48 +02:00
Lennert Buytenhek b206ed0462 [ARM] Orion: remove error printks in ->map_irq() implementations
If all PCI devices are working as expected, the error printks in the
various implementations of ->map_irq() doesn't really provide any
useful info.  And if something is not working as expected, turning
on pci=debug gives you more useful information than the printk calls
in ->map_irq(), since the former also tells you which devices _did_
get IRQs successfully assigned.  Therefore, delete these printks
entirely.

Spotted by Russell King.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22 22:44:47 +02:00
Lennert Buytenhek 19cfd5c09f [ARM] Orion: rework MPP handling
Instead of having board code poke directly into the MPP configuration
registers, and separately calling orion5x_gpio_set_valid_pins() to
indicate which MPP pins can be used as GPIO pins, introduce a helper
function for configuring the roles of each of the MPP pins, and have
that helper function handle gpio validity internally.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Sylver Bruneau <sylver.bruneau@googlemail.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22 22:44:47 +02:00
Lennert Buytenhek 386a048a1e [ARM] Orion: move setting up PCIe WA window into PCIe setup path
It makes no sense to do PCIe WA window setup in the individual
board support files while the decision whether or not to use the
PCIe WA access method is made in a different place, in the PCIe
support code.

This patch moves the configuration of a PCIe WA window from the
individual Orion board support files to the central Orion PCIe
support code.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22 22:44:46 +02:00
Lennert Buytenhek 044f6c7c44 [ARM] Orion: move EHCI/I2C/UART peripheral init into board code
This patch moves initialisation of EHCI/I2C/UART platform devices
from the common orion5x_init() into the board support code.

The rationale behind this is that only the board support code knows
whether certain peripherals have been brought out on the board, and
not initialising peripherals that haven't been brought out is
desirable for example:
- to reduce user confusion (e.g. seeing both 'eth0' and 'eth1'
  appear while there is only one ethernet port on the board); and
- to allow for future power savings (peripherals that have not
  been brought out can be clock gated off entirely).

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22 22:44:45 +02:00
Lennert Buytenhek 000e99c333 [ARM] Orion: top-level IRQs are level-triggered
Make it clear that Orion top-level IRQs are level-triggered.  This
means that we don't need an ->ack() handler, or at least, we don't
need the ->ack() handler (or the acking part of the ->mask_ack()
handler) to actually do anything.

Given that, we might as well point our ->mask_ack() handler at the
->mask() handler instead of providing a dummy ->ack() handler, since
providing a ->mask_ack() handler on level IRQ sources will prevent
->ack() from ever being called.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22 22:44:43 +02:00
Lennert Buytenhek ee0dd84005 [ARM] Feroceon: annotate 88fr531-vd CPU entries
Annotate the entries for the 88fr531-vd CPU core in
arch/arm/boot/compressed/head.S and arch/arm/mm/proc-feroceon.S
with the full name of the core.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22 22:44:42 +02:00
Lennert Buytenhek 4fc338e38f [ARM] Orion: DRAM mapping granularity is 64KiB, not 16MiB
The DRAM base address and size fields in the CPU's MBUS bridge have
64KiB granularity, instead of the currently used 16MiB.  Since all
of the currently supported MBUS peripherals support 64KiB granularity
as well, this patch changes the Orion address map code to stop
rounding base addresses down and sizes up to multiples of 16MiB.

Found by Ke Wei <kewei@marvell.com>.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22 22:44:41 +02:00
Lennert Buytenhek a18b658449 [ARM] Orion: make window setup a little more safe
Currently, Orion window setup uses hardcoded window indexes for each
of the boot/cs0/cs1/cs2/PCIe WA windows.  The static window allocation
used can clash if board support code will ever attempt to configure
both a dev2 and a PCIe WA window, as both of those use CPU mbus window
#7 at present.

This patch keeps track of the last used window, and opens subsequently
requested windows sequentially, starting from 4.  (Windows 0-3 are used
as MEM/IO windows for the PCI/PCIe buses.)

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:40 +02:00
Lennert Buytenhek e7068ad337 [ARM] Orion: fix various whitespace and coding style issues
More cosmetic cleanup:
- Replace 8-space indents by proper tab indents.
- In structure initialisers, use a trailing comma for every member.
- Collapse "},\n{" in structure initialiers to "}, {".

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22 22:44:39 +02:00
Nicolas Pitre f91a8dcc25 [ARM] cache align memset and memzero
This is a natural extension following the previous patch.
Non Feroceon based targets are unchanged.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:39 +02:00
Nicolas Pitre 2239aff6ab [ARM] cache align destination pointer when copying memory for some processors
The implementation for memory copy functions on ARM had a (disabled)
provision for aligning the source pointer before loading registers with
data.  Turns out that aligning the _destination_ pointer is much more
useful, as the read side is already sufficiently helped with the use of
preload.

So this changes the definition of the CALGN() macro to target the
destination pointer instead, and turns it on for Feroceon processors
where the gain is very noticeable.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:38 +02:00
Nicolas Pitre 4c4925c1f4 [ARM] fix cache alignment code in memset.S
This code is currently disabled, which explains why no one was affected.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:37 +02:00
Nicolas Pitre f76e915473 [ARM] latencytop support
Available for !SMP only at the moment.

From Russell:

|Basically, if a thread is running on a CPU, thread_saved_fp() is invalid.
|So, the question is: what guarantees do we have here that 'tsk' is not
|running on another CPU?

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Tested-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:36 +02:00
Nicolas Pitre b0bfcce930 [ARM] Orion: update defconfig to 2.6.26-rc4
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:35 +02:00
Linus Torvalds b1ae8d3a00 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, geode: add a VSA2 ID for General Software
  x86: use BOOTMEM_EXCLUSIVE on 32-bit
  x86, 32-bit: fix boot failure on TSC-less processors
  x86: fix NULL pointer deref in __switch_to
  x86: set PAE PHYSICAL_MASK_SHIFT to 44 bits.
2008-06-20 12:36:38 -07:00
Linus Torvalds 89f5b7da2a Reinstate ZERO_PAGE optimization in 'get_user_pages()' and fix XIP
KAMEZAWA Hiroyuki and Oleg Nesterov point out that since the commit
557ed1fa26 ("remove ZERO_PAGE") removed
the ZERO_PAGE from the VM mappings, any users of get_user_pages() will
generally now populate the VM with real empty pages needlessly.

We used to get the ZERO_PAGE when we did the "handle_mm_fault()", but
since fault handling no longer uses ZERO_PAGE for new anonymous pages,
we now need to handle that special case in follow_page() instead.

In particular, the removal of ZERO_PAGE effectively removed the core
file writing optimization where we would skip writing pages that had not
been populated at all, and increased memory pressure a lot by allocating
all those useless newly zeroed pages.

This reinstates the optimization by making the unmapped PTE case the
same as for a non-existent page table, which already did this correctly.

While at it, this also fixes the XIP case for follow_page(), where the
caller could not differentiate between the case of a page that simply
could not be used (because it had no "struct page" associated with it)
and a page that just wasn't mapped.

We do that by simply returning an error pointer for pages that could not
be turned into a "struct page *".  The error is arbitrarily picked to be
EFAULT, since that was what get_user_pages() already used for the
equivalent IO-mapped page case.

[ Also removed an impossible test for pte_offset_map_lock() failing:
  that's not how that function works ]

Acked-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Nick Piggin <npiggin@suse.de>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-06-20 11:18:25 -07:00
Jordan Crouse ffe6e1da86 x86, geode: add a VSA2 ID for General Software
General Software writes their own VSA2 module for their version
of the Geode BIOS, which returns a different ID then the standard
VSA2.  This was causing the framebuffer driver to break for most
GSW boards.

Signed-off-by: Jordan Crouse <jordan.crouse@amd.com>
Cc: tglx@linutronix.de
Cc: linux-geode@lists.infradead.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-19 14:19:03 +02:00
Bernhard Walle d3942cff62 x86: use BOOTMEM_EXCLUSIVE on 32-bit
This patch uses the BOOTMEM_EXCLUSIVE for crashkernel reservation also for
i386 and prints a error message on failure.

The patch is still for 2.6.26 since it is only bug fixing. The unification
of reserve_crashkernel() between i386 and x86_64 should be done for 2.6.27.

Signed-off-by: Bernhard Walle <bwalle@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
2008-06-19 10:08:48 +02:00
Mikael Pettersson df17b1d990 x86, 32-bit: fix boot failure on TSC-less processors
Booting 2.6.26-rc6 on my 486 DX/4 fails with a "BUG: Int 6"
(invalid opcode) and a kernel halt immediately after the
kernel has been uncompressed. The BUG shows EIP pointing
to an rdtsc instruction in native_read_tsc(), invoked from
native_sched_clock().

(This error occurs so early that not even the serial console
can capture it.)

A bisection showed that this bug first occurs in 2.6.26-rc3-git7,
via commit 9ccc906c97e34fd91dc6aaf5b69b52d824386910:

>x86: distangle user disabled TSC from unstable
>
>tsc_enabled is set to 0 from the command line switch "notsc" and from
>the mark_tsc_unstable code. Seperate those functionalities and replace
>tsc_enable with tsc_disable. This makes also the native_sched_clock()
>decision when to use TSC understandable.
>
>Preparatory patch to solve the sched_clock() issue on 32 bit.
>
>Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

The core reason for this bug is that native_sched_clock() gets
called before tsc_init().

Before the commit above, tsc_32.c used a "tsc_enabled" variable
which defaulted to 0 == disabled, and which only got enabled late
in tsc_init(). Thus early calls to native_sched_clock() would skip
the TSC and use jiffies instead.

After the commit above, tsc_32.c uses a "tsc_disabled" variable
which defaults to 0, meaning that the TSC is Ok to use. Early calls
to native_sched_clock() now erroneously try to use the TSC on
!cpu_has_tsc processors, leading to invalid opcode exceptions.

My proposed fix is to initialise tsc_disabled to a "soft disabled"
state distinct from the hard disabled state set up by the "notsc"
kernel option. This fixes the native_sched_clock() problem. It also
allows tsc_init() to be simplified: instead of setting tsc_disabled = 1
on every error return, we just set tsc_disabled = 0 once when all
checks have succeeded.

I've verified that this lets my 486 boot again. I've also verified
that a Core2 machine still uses the TSC as clocksource after the patch.

Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-19 10:08:47 +02:00
Suresh Siddha 75118a82e2 x86: fix NULL pointer deref in __switch_to
Patrick McHardy reported a crash:

> > I get this oops once a day, its apparently triggered by something
> > run by cron, but the process is a different one each time.
> >
> > Kernel is -git from yesterday shortly before the -rc6 release
> > (last commit is the usb-2.6 merge, the x86 patches are missing),
> > .config is attached.
> >
> > I'll retry with current -git, but the patches that have gone in
> > since I last updated don't look related.
> >
> > [62060.043009] BUG: unable to handle kernel NULL pointer dereference at
> > 000001ff
> > [62060.043009] IP: [<c0102a9b>] __switch_to+0x2f/0x118
> > [62060.043009] *pde = 00000000
> > [62060.043009] Oops: 0002 [#1] PREEMPT

Vegard Nossum analyzed it:

> This decodes to
>
>    0:   0f ae 00                fxsave (%eax)
>
> so it's related to the floating-point context. This is the exact
> location of the crash:
>
> $ addr2line -e arch/x86/kernel/process_32.o -i ab0
> include/asm/i387.h:232
> include/asm/i387.h:262
> arch/x86/kernel/process_32.c:595
>
> ...so it looks like prev_task->thread.xstate->fxsave has become NULL.
> Or maybe it never had any other value.

Somehow (as described below) TS_USEDFPU is set but the fpu is not
allocated or freed.

Another possible FPU pre-emption issue with the sleazy FPU optimization
which was benign before but not so anymore, with the dynamic FPU allocation
patch.

New task is getting exec'd and it is prempted at the below point.

flush_thread() {
	...
	/*
	* Forget coprocessor state..
	*/
	clear_fpu(tsk);
		<----- Preemption point
	clear_used_math();
	...
}

Now when it context switches in again, as the used_math() is still set
and fpu_counter can be > 5, we will do a math_state_restore() which sets
the task's TS_USEDFPU. After it continues from the above preemption point
it does clear_used_math() and much later free_thread_xstate().

Now, at the next context switch, it is quite possible that xstate is
null, used_math() is not set and TS_USEDFPU is still set. This will
trigger unlazy_fpu() causing kernel oops.

Fix this  by clearing tsk's fpu_counter before clearing task's fpu.

Reported-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-19 10:08:45 +02:00
Paul Mackerras 65ba6cdc83 [POWERPC] Clear sub-page HPTE present bits when demoting page size
When we demote a slice from 64k to 4k, and we are about to insert an
HPTE for a 4k subpage and we notice that there is an existing 64k
HPTE, we first invalidate that HPTE before inserting the new 4k
subpage HPTE.  Since the bits that encode which hash bucket the old
HPTE was in overlap with the bits that encode which of the 16 subpages
have HPTEs, we need to clear out the subpage HPTE-present bits before
starting to insert HPTEs for the 4k subpages.  If we don't do that, we
can erroneously think that a subpage already has an HPTE when it
doesn't.

That in itself wouldn't be such a problem except that when we go to
update the HPTE that we think is present on machines with a
hypervisor, the hypervisor can tell us that the HPTE we think is there
is actually there even though it isn't, which can lead to a process
getting stuck in a loop, continually faulting.  The reason for the
confusion is that the AVPN (abbreviated virtual page number) we are
looking for in the HPTE for a 4k subpage can actually match the AVPN
in a stale HPTE for another 64k page.  For example, the HPTE for
the 4k subpage at 0x84000f000 will be in the same hash bucket and have
the same AVPN as the HPTE for the 64k page at 0x8400f0000.

This fixes the code to clear out the subpage HPTE-present bits.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-18 21:40:43 +10:00
Josh Boyer b17879f71c [POWERPC] 4xx: Clear new TLB cache attribute bits in Data Storage vector
A recent commit added support for the new 440x6 and 464 cores that have the
added WL1, IL1I, IL1D, IL2I, and ILD2 bits for the caching attributes in the
TLBs.  The new bits were cleared in the finish_tlb_load function, however a
similar bit of code was missed in the DataStorage interrupt vector.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-18 21:40:43 +10:00
Linus Torvalds 42a886af72 x86-64: Fix "bytes left to copy" return value for copy_from_user()
Most users by far do not care about the exact return value (they only
really care about whether the copy succeeded in its entirety or not),
but a few special core routines actually care deeply about exactly how
many bytes were copied from user space.

And the unrolled versions of the x86-64 user copy routines would
sometimes report that it had copied more bytes than it actually had.

Very few uses actually have partial copies to begin with, but to make
this bug even harder to trigger, most x86 CPU's use the "rep string"
instructions for normal user copies, and that version didn't have this
issue.

To make it even harder to hit, the one user of this that really cared
about the return value (and used the uncached version of the copy that
doesn't use the "rep string" instructions) was the generic write
routine, which pre-populated its source, once more hiding the problem by
avoiding the exception case that triggers the bug.

In other words, very special thanks to Bron Gondwana who not only
triggered this, but created a test-program to show it, and bisected the
behavior down to commit 08291429cf ("mm:
fix pagecache write deadlocks") which changed the access pattern just
enough that you can now trigger it with 'writev()' with multiple
iovec's.

That commit itself was not the cause of the bug, it just allowed all the
stars to align just right that you could trigger the problem.

[ Side note: this is just the minimal fix to make the copy routines
  (with __copy_from_user_inatomic_nocache as the particular version that
  was involved in showing this) have the right return values.

  We really should improve on the exceptional case further - to make the
  copy do a byte-accurate copy up to the exact page limit that causes it
  to fail.  As it is, the callers have to do extra work to handle the
  limit case gracefully. ]

Reported-by: Bron Gondwana <brong@fastmail.fm>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

 (which didn't have this problem), and since
most users that do the carethis was very hard to trigger, but
2008-06-17 17:47:50 -07:00
Linus Torvalds c8988f9682 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
  [IA64] Fix CONFIG_IA64_SGI_UV build error
  [IA64] Update check_sal_cache_flush to use platform_send_ipi()
  [IA64] perfmon: fix async exit bug
2008-06-16 11:52:43 -07:00
Linus Torvalds 10acaf0c8a Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (21 commits)
  [POWERPC] Turn on ATA_SFF so we get SATA_SVW back in defconfigs
  [POWERPC] Remove ppc32's export of console_drivers
  [POWERPC] Fix -Os kernel builds with newer gcc versions
  [POWERPC] Fix bootwrapper builds with newer gcc versions
  [POWERPC] Build fix for drivers/macintosh/mediabay.c
  [POWERPC] Fix warning in pseries/eeh_driver.c
  [POWERPC] Add missing of_node_put in drivers/macintosh/therm_adt746x.c
  [POWERPC] Add missing of_node_put in drivers/macintosh/smu.c
  [POWERPC] Add missing of_node_put in pseries/nvram.c
  [POWERPC] Fix return value check logic in debugfs virq_mapping setup
  [POWERPC] Fix rmb to order cacheable vs. noncacheable
  powerpc/spufs: fix missed stop-and-signal event
  powerpc/spufs: synchronize interaction between spu exception handling and time slicing
  powerpc/spufs: remove class_0_dsisr from spu exception handling
  powerpc/spufs: wait for stable spu status in spu_stopped()
  [POWERPC] bootwrapper: add simpleImage* to list of boot targets
  [POWERPC] 83xx: MPC837xRDB's VSC7385 ethernet switch isn't on the MDIO bus
  [POWERPC] Updated Freescale PPC defconfigs
  [POWERPC] 8610: Update defconfig for MPC8610 HPCD
  [POWERPC] 85xx: MPC8548CDS - Fix size of PCIe IO space
  ...
2008-06-16 10:24:01 -07:00