The LPAE page table format uses 64-bit descriptors, so we need to take
endianness into account when populating the swapper and idmap tables
during early initialisation.
This patch ensures that we store the two words making up each page table
entry in the correct order when running big-endian.
Cc: <stable@vger.kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When booting a SMP build kernel with nosmp on kernel cmdline, the
following fat warning will be hit.
------------[ cut here ]------------
WARNING: at arch/arm/kernel/smp_twd.c:345
twd_local_timer_of_register+0x7c/0x90()
twd_local_timer_of_register failed (-6)
Modules linked in:
Backtrace:
[<80011f14>] (dump_backtrace+0x0/0x10c) from [<8044dd30>]
(dump_stack+0x18/0x1c)
r7:805e9f58 r6:805ba84c r5:80539331 r4:00000159
[<8044dd18>] (dump_stack+0x0/0x1c) from [<80020fbc>]
(warn_slowpath_common+0x54/0x6c)
[<80020f68>] (warn_slowpath_common+0x0/0x6c) from [<80021078>]
(warn_slowpath_fmt+0x38/0x40)
r9:412fc09a r8:8fffffff r7:ffffffff r6:00000001 r5:80633b8c
r4:80b32da8
[<80021040>] (warn_slowpath_fmt+0x0/0x40) from [<805ba84]
(twd_local_timer_of_register+0x7c/0x90)
r3:fffffffa r2:8053934b
[<805ba7d0>] (twd_local_timer_of_register+0x0/0x90) from [<805c0bec>]
(imx6q_timer_init+0x18/0x4c)
r5:80633800 r4:8053b701
[<805c0bd4>] (imx6q_timer_init+0x0/0x4c) from [<805ba4e8>]
(time_init+0x28/0x38)
r5:80633800 r4:805dc0f4
[<805ba4c0>] (time_init+0x0/0x38) from [<805b6854>]
(start_kernel+0x1a0/0x310)
[<805b66b4>] (start_kernel+0x0/0x310) from [<10008044>] (0x10008044)
r8:1000406a r7:805f3f8c r6:805dc0c4 r5:805f0518 r4:10c5387d
---[ end trace 1b75b31a2719ed1c ]---
Check (!is_smp() || !setup_max_cpus) in twd_local_timer_of_register()
to make it be a no-op for the conditions, thus avoid above warning.
Reported-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fix missing use of the asid macro when getting the ASID from the mm->context.id field.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The Netx IRQs offset from zero, which is illegal, since Linux
IRQ 0 is NO_IRQ.
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull more VFS bits from Al Viro:
"Unfortunately, it looks like xattr series will have to wait until the
next cycle ;-/
This pile contains 9p cleanups and fixes (races in v9fs_fid_add()
etc), fixup for nommu breakage in shmem.c, several cleanups and a bit
more file_inode() work"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
constify path_get/path_put and fs_struct.c stuff
fix nommu breakage in shmem.c
cache the value of file_inode() in struct file
9p: if v9fs_fid_lookup() gets to asking server, it'd better have hashed dentry
9p: make sure ->lookup() adds fid to the right dentry
9p: untangle ->lookup() a bit
9p: double iput() in ->lookup() if d_materialise_unique() fails
9p: v9fs_fid_add() can't fail now
v9fs: get rid of v9fs_dentry
9p: turn fid->dlist into hlist
9p: don't bother with private lock in ->d_fsdata; dentry->d_lock will do just fine
more file_inode() open-coded instances
selinux: opened file can't have NULL or negative ->f_path.dentry
(In the meantime, the hlist traversal macros have changed, so this
required a semantic conflict fixup for the newly hlistified fid->dlist)
Pull second set of s390 patches from Martin Schwidefsky:
"The main part of this merge are Heikos uaccess patches. Together with
commit 0988496433 ("mm: do not grow the stack vma just because of an
overrun on preceding vma") the user string access is hopefully fixed
for good.
In addition some bug fixes and two cleanup patches."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/module: fix compile warning
qdio: remove unused parameters
s390/uaccess: fix kernel ds access for page table walk
s390/uaccess: fix strncpy_from_user string length check
input: disable i8042 PC Keyboard controller for s390
s390/dis: Fix invalid array size
s390/uaccess: remove pointless access_ok() checks
s390/uaccess: fix strncpy_from_user/strnlen_user zero maxlen case
s390/uaccess: shorten strncpy_from_user/strnlen_user
s390/dasd: fix unresponsive device after all channel paths were lost
s390/mm: ignore change bit for vmemmap
s390/page table dumper: add support for change-recording override bit
Pull second round of PARISC updates from Helge Deller:
"The most important fix in this branch is the switch of io_setup,
io_getevents and io_submit syscalls to use the available compat
syscalls when running 32bit userspace on 64bit kernel. Other than
that it's mostly removal of compile warnings."
* 'fixes-for-3.9-latest' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: fix redefinition of SET_PERSONALITY
parisc: do not install modules when installing kernel
parisc: fix compile warnings triggered by atomic_sub(sizeof(),v)
parisc: check return value of down_interruptible() in hp_sdc_rtc.c
parisc: avoid unitialized variable warning in pa_memcpy()
parisc: remove unused variable 'compat_val'
parisc: switch to compat_functions of io_setup, io_getevents and io_submit
parisc: select ARCH_WANT_FRAME_POINTERS
This adds core architecture support for Imagination's Meta processor
cores, followed by some later miscellaneous arch/metag cleanups and
fixes which I kept separate to ease review:
- Support for basic Meta 1 (ATP) and Meta 2 (HTP) core architecture
- A few fixes all over, particularly for symbol prefixes
- A few privilege protection fixes
- Several cleanups (setup.c includes, split out a lot of metag_ksyms.c)
- Fix some missing exports
- Convert hugetlb to use vm_unmapped_area()
- Copy device tree to non-init memory
- Provide dma_get_sgtable()
Signed-off-by: James Hogan <james.hogan@imgtec.com>
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Merge tag 'metag-v3.9-rc1-v4' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag
Pull new ImgTec Meta architecture from James Hogan:
"This adds core architecture support for Imagination's Meta processor
cores, followed by some later miscellaneous arch/metag cleanups and
fixes which I kept separate to ease review:
- Support for basic Meta 1 (ATP) and Meta 2 (HTP) core architecture
- A few fixes all over, particularly for symbol prefixes
- A few privilege protection fixes
- Several cleanups (setup.c includes, split out a lot of
metag_ksyms.c)
- Fix some missing exports
- Convert hugetlb to use vm_unmapped_area()
- Copy device tree to non-init memory
- Provide dma_get_sgtable()"
* tag 'metag-v3.9-rc1-v4' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag: (61 commits)
metag: Provide dma_get_sgtable()
metag: prom.h: remove declaration of metag_dt_memblock_reserve()
metag: copy devicetree to non-init memory
metag: cleanup metag_ksyms.c includes
metag: move mm/init.c exports out of metag_ksyms.c
metag: move usercopy.c exports out of metag_ksyms.c
metag: move setup.c exports out of metag_ksyms.c
metag: move kick.c exports out of metag_ksyms.c
metag: move traps.c exports out of metag_ksyms.c
metag: move irq enable out of irqflags.h on SMP
genksyms: fix metag symbol prefix on crc symbols
metag: hugetlb: convert to vm_unmapped_area()
metag: export clear_page and copy_page
metag: export metag_code_cache_flush_all
metag: protect more non-MMU memory regions
metag: make TXPRIVEXT bits explicit
metag: kernel/setup.c: sort includes
perf: Enable building perf tools for Meta
metag: add boot time LNKGET/LNKSET check
metag: add __init to metag_cache_probe()
...
Pull late ARM updates from Russell King:
"Here is the late set of ARM updates for this merge window; in here is:
- The ARM parts of the broadcast timer support, core parts merged
through tglx's tree. This was left over from the previous merge to
allow the dependency on tglx's tree to be resolved.
- A fix to the VFP code which shows up on Raspberry Pi's, as well as
fixing the fallout from a previous commit in this area.
- A number of smaller fixes scattered throughout the ARM tree"
* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm:
ARM: Fix broken commit 0cc41e4a21 corrupting kernel messages
ARM: fix scheduling while atomic warning in alignment handling code
ARM: VFP: fix emulation of second VFP instruction
ARM: 7656/1: uImage: Error out on build of multiplatform without LOADADDR
ARM: 7640/1: memory: tegra_ahb_enable_smmu() depends on TEGRA_IOMMU_SMMU
ARM: 7654/1: Preserve L_PTE_VALID in pte_modify()
ARM: 7653/2: do not scale loops_per_jiffy when using a constant delay clock
ARM: 7651/1: remove unused smp_timer_broadcast #define
Pull watchdog updates from Wim Van Sebroeck:
"This contains:
- fixes and improvements
- devicetree bindings
- conversion to watchdog generic framework of the following drivers:
- booke_wdt
- bcm47xx_wdt.c
- at91sam9_wdt
- Removal of old STMP3xxx driver
- Addition of following new drivers:
- new driver for STMP3xxx and i.MX23/28
- Retu watchdog driver"
* git://www.linux-watchdog.org/linux-watchdog: (30 commits)
watchdog: sp805_wdt depends on ARM
watchdog: davinci_wdt: update to devm_* API
watchdog: davinci_wdt: use devm managed clk get
watchdog: at91rm9200: add DT support
watchdog: add timeout-sec property binding
watchdog: at91sam9_wdt: Convert to use the watchdog framework
watchdog: omap_wdt: Add option nowayout
watchdog: core: dt: add support for the timeout-sec dt property
watchdog: bcm47xx_wdt.c: add hard timer
watchdog: bcm47xx_wdt.c: rename wdt_time to timeout
watchdog: bcm47xx_wdt.c: rename ops methods
watchdog: bcm47xx_wdt.c: use platform device
watchdog: bcm47xx_wdt.c: convert to watchdog core api
watchdog: Convert BookE watchdog driver to watchdog infrastructure
watchdog: s3c2410_wdt: Use devm_* functions
watchdog: remove old STMP3xxx driver
watchdog: add new driver for STMP3xxx and i.MX23/28
rtc: stmp3xxx: add wdt-accessor function
watchdog: introduce retu_wdt driver
watchdog: intel_scu_watchdog: fix Kconfig dependency
...
metag/allmodconfig:
drivers/media/v4l2-core/videobuf2-dma-contig.c: In function 'vb2_dc_get_base_sgt':
drivers/media/v4l2-core/videobuf2-dma-contig.c:387: error: implicit declaration of function 'dma_get_sgtable'
For architectures using dma_map_ops, dma_get_sgtable() is provided in
<asm-generic/dma-mapping-common.h>.
Metag does not use dma_map_ops yet, hence it should implement it as an
inline stub using dma_common_get_sgtable().
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Metag doesn't have a metag_dt_memblock_reserve() function so remove the
declaration from asm/prom.h.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Make a copy of the device tree blob in non-init memory. It is required
when using built-in device tree files that the platform code copies the
blob to non-init memory prior to calling unflatten_device_tree(),
otherwise the strings that the device tree refer to will get poisoned
and potentially reused, breaking later reading of the device tree
post-init (such as compatible matching in modules, debugfs, and the
procfs interface).
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Vineet Gupta <vgupta@synopsys.com>
Minimise metag_ksyms.c includes to directly include the <asm/*.h> files
that declare a particular symbol, and not include any unnecessary ones.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
It's less error prone to have function symbols exported immediately
after the function rather than in metag_ksyms.c. Move each EXPORT_SYMBOL
in metag_ksyms.c for symbols defined in mm/init.c into mm/init.c.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
It's less error prone to have function symbols exported immediately
after the function rather than in metag_ksyms.c. Move each EXPORT_SYMBOL
in metag_ksyms.c for symbols defined in usercopy.c into usercopy.c
Signed-off-by: James Hogan <james.hogan@imgtec.com>
It's less error prone to have function symbols exported immediately
after the function rather than in metag_ksyms.c. Move each EXPORT_SYMBOL
in metag_ksyms.c for symbols defined in setup.c into setup.c
Signed-off-by: James Hogan <james.hogan@imgtec.com>
It's less error prone to have function symbols exported immediately
after the function rather than in metag_ksyms.c. Move each EXPORT_SYMBOL
in metag_ksyms.c for symbols defined in kick.c into kick.c
Signed-off-by: James Hogan <james.hogan@imgtec.com>
It's less error prone to have function symbols exported immediately
after the function rather than in metag_ksyms.c. Move each EXPORT_SYMBOL
in metag_ksyms.c for symbols defined in traps.c into traps.c
Signed-off-by: James Hogan <james.hogan@imgtec.com>
The SMP version of arch_local_irq_enable() uses preempt_disable(), but
<asm/irqflags.h> doesn't include <linux/preempt.h> causing the following
errors on SMP when pstore/ftrace is enabled (caught by buildbot smp
allyesconfig):
In file included from include/linux/irqflags.h:15,
from fs/pstore/ftrace.c:16:
arch/metag/include/asm/irqflags.h: In function 'arch_local_irq_enable':
arch/metag/include/asm/irqflags.h:84: error: implicit declaration of function 'preempt_disable'
arch/metag/include/asm/irqflags.h:86: error: implicit declaration of function 'preempt_enable_no_resched'
However <linux/preempt.h> cannot be easily included from
<asm/irqflags.h> as it can cause circular include dependencies in the
!SMP case, and potentially in the SMP case in the future. Therefore move
the SMP implementation of arch_local_irq_enable() into traps.c and use
an inline version of get_trigger_mask() which is also defined in traps.c
for SMP.
This adds an extra layer of function call / stack push when
preempt_disable needs to call other functions, however in the
non-preemptive SMP case it should be about as fast, as it was already
calling the get_trigger_mask() function which is now used inline.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Convert hugetlb_get_unmapped_area_new_pmd() to use vm_unmapped_area()
rather than searching the virtual address space itself. This fixes the
following errors in linux-next due to the specified members being
removed after other architectures have already been converted:
arch/metag/mm/hugetlbpage.c: In function 'hugetlb_get_unmapped_area_new_pmd':
arch/metag/mm/hugetlbpage.c:199: error: 'struct mm_struct' has no member named 'cached_hole_size'
arch/metag/mm/hugetlbpage.c:200: error: 'struct mm_struct' has no member named 'free_area_cache'
arch/metag/mm/hugetlbpage.c:215: error: 'struct mm_struct' has no member named 'cached_hole_size'
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Michel Lespinasse <walken@google.com>
Various file systems use clear_page() and copy_page(), so when they're
built as modules we get build errors like the following:
ERROR: "clear_page" [fs/ntfs/ntfs.ko] undefined!
ERROR: "copy_page" [fs/nilfs2/nilfs2.ko] undefined!
Therefore export these functions to modules from metag_ksyms.c to fix
the errors. This was hit by a randconfig build.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Various file systems indirectly use metag_code_cache_flush_all(), so
when they're built as modules we get build errors like the following:
ERROR: "metag_code_cache_flush_all" [fs/xfs/xfs.ko] undefined!
Therefore export this function to modules to fix the errors. This was
hit by a randconfig build.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Rename setup_txprivext() to setup_priv() and add initialisation of some
more per-thread privilege protection registers:
- TxPRIVSYSR: 0x04400000-0x047fffff
0x05000000-0x07ffffff
0x84000000-0x87ffffff
- TxPIOREG: 0x02000000-0x02ffffff
0x04800000-0x048fffff
- TxSYREG: 0x04000000-0x04000fff (except write fetch system event)
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Define PRIV_BITS using explicit constants from <asm/metag_regs.h> rather
than with a hard coded value. This also adds a couple of missing
definitions for the TXPRIVEXT priv bits for protecting writes to TXTIMER
and the trace registers.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Add boot time check for whether LNKGET/LNKSET go through or around the
cache. Depending on the configuration an info message (no harm), warning
(technically wrong but no harm), or big WARN (expect failure in either
kernel or userland) may be emitted if the behaviour is not as expected:
Configuration Hardware Response
------------------------------------------ -------- --------
AROUND_CACHE through pr_info
!AROUND_CACHE && ATOMICITY_LNKGET around WARN (kernel)
" && !ATOMICITY_LNKGET && SMP around WARN (user)
" " && !SMP around pr_warn
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Add basic JTAG Debug Adapter (DA) support so that drivers which
communicate with the DA can detect whether one is actually present
(otherwise the target will halt indefinitely).
This allows the metag_da TTY driver and imgdafs filesystem driver to be
built, updates defconfigs, and sets up the metag_da console early if
it's configured in.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Add Perf support for metag.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Add SMP support for metag. This allows Linux to take control of multiple
hardware threads on a single Meta core, treating them as separate Linux
CPUs.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Add header files to implement Meta hardware thread locks (used by some
other atomic operations), atomics, spinlocks, and bitops.
There are 2 main types of atomic primitives for metag (in addition to
IRQs off on UP):
- LOCK instructions provide locking between hardware threads.
- LNKGET/LNKSET instructions provide load-linked/store-conditional
operations allowing for lighter weight atomics on Meta2
LOCK instructions allow for hardware threads to acquire voluntary or
exclusive hardware thread locks:
- LOCK0 releases exclusive and voluntary lock from the running hardware
thread.
- LOCK1 acquires the voluntary hardware lock, blocking until it becomes
available.
- LOCK2 implies LOCK1, and additionally acquires the exclusive hardware
lock, blocking all other hardware threads from executing.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Add metag system call and gateway page interfaces. The metag
architecture port uses the generic system call numbers from
asm-generic/unistd.h, as well as a user gateway page mapped at
0x6ffff000 which contains fast atomic primitives (depending on SMP) and
a fast method of accessing TLS data.
System calls use the SWITCH instruction with the immediate 0x440001 to
signal a system call.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Meta core internal interrupts (from HWSTATMETA and friends) are vectored
onto the TR1 core trigger for the current thread. This is demultiplexed
in irq-metag.c to individual Linux IRQs for each internal interrupt.
External SoC interrupts (from HWSTATEXT and friends) are vectored onto
the TR2 core trigger for the current thread. This is demultiplexed in
irq-metag-ext.c to individual Linux IRQs for each external SoC interrupt.
The external irqchip has devicetree bindings for configuring the number
of irq banks and the type of masking available.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
Cc: Dom Cobley <popcornmix@gmail.com>
Cc: Simon Arlott <simon@fire.lp0.eu>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: linux-doc@vger.kernel.org
Add trap code for metag. At the lowest level Meta traps (and return from
interrupt instruction - RTI) simply swap the PC and PCX registers and
optionally toggle the interrupt status bit (ISTAT). Low level TBX code
in tbipcx.S handles the core context save, determine the TBX signal
number based on the core trigger that fired (using the TXSTATI status
register), and call TBX signal handlers (mostly in traps.c) via a vector
table.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Add time keeping code for metag. Meta hardware threads have 2 timers.
The background timer (TXTIMER) is used as a free-running time base, and
the interrupt timer (TXTIMERI) is used for the timer interrupt. Both
counters traditionally count at approximately 1MHz.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
The ptrace interface for metag provides access to some core register
sets using the PTRACE_GETREGSET and PTRACE_SETREGSET operations. The
details of the internal context structures is abstracted into user API
structures to both ease use and allow flexibility to change the internal
context layouts. Copyin and copyout functions for these register sets
are exposed to allow signal handling code to use them to copy to and
from the signal context.
struct user_gp_regs (NT_PRSTATUS) provides access to the core general
purpose register context.
struct user_cb_regs (NT_METAG_CBUF) provides access to the TXCATCH*
registers which contains information abuot a memory fault, unaligned
access error or watchpoint. This can be modified to alter the way the
fault is replayed on resume ("catch replay"), or to prevent the replay
taking place.
struct user_rp_state (NT_METAG_RPIPE) provides access to the state of
the Meta read pipeline which can be used to hide memory latencies in
hand optimised data loops.
Extended DSP register state, DSP RAM, and hardware breakpoint registers
aren't yet exposed through ptrace.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Tony Lindgren <tony@atomide.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>