Commit Graph

15 Commits

Author SHA1 Message Date
Ard Biesheuvel 13d1b9575a ARM: 8221/1: PJ4: allow building in Thumb-2 mode
Two files that get included when building the multi_v7_defconfig target
fail to build when selecting THUMB2_KERNEL for this configuration.

In both cases, we can just build the file as ARM code, as none of its
symbols are exported to modules, so there are no interworking concerns.
In the iwmmxt.S case, add ENDPROC() declarations so the symbols are
annotated as functions, resulting in the linker to emit the appropriate
mode switches.

Acked-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-12-03 16:08:00 +00:00
Russell King 7109561524 Merge branches 'fixes' and 'misc' into for-next
Conflicts:
	arch/arm/kernel/iwmmxt.S
	arch/arm/mm/cache-l2x0.c
	arch/arm/mm/mmu.c
2014-08-05 10:27:13 +01:00
Sebastian Hesselbarth 8cf2389bc4 ARM: 8100/1: Fix preemption disable in iwmmxt_task_enable()
commit 431a84b1a4
 ("ARM: 8034/1: Disable preemption in iwmmxt_task_enable()")
introduced macros {inc,dec}_preempt_count to iwmmxt_task_enable
to make it run with preemption disabled.

Unfortunately, other functions in iwmmxt.S also use concan_{save,dump,load}
sections located in iwmmxt_task_enable() to deal with iWMMXt coprocessor.
This causes an unbalanced preempt_count due to excessive dec_preempt_count
and destroyed return addresses in callers of concan_ labels due to a register
collision:

Linux version 3.16.0-rc3-00062-gd92a333-dirty (jef@armhf) (gcc version 4.8.3 (Debian 4.8.3-4) ) #5 PREEMPT Thu Jul 3 19:46:39 CEST 2014
CPU: ARMv7 Processor [560f5815] revision 5 (ARMv7), cr=10c5387d
CPU: PIPT / VIPT nonaliasing data cache, PIPT instruction cache
Machine model: SolidRun CuBox
...
PJ4 iWMMXt v2 coprocessor enabled.
...
Unable to handle kernel paging request at virtual address fffffffe
pgd = bb25c000
[fffffffe] *pgd=3bfde821, *pte=00000000, *ppte=00000000
Internal error: Oops: 80000007 [#1] PREEMPT ARM
Modules linked in:
CPU: 0 PID: 62 Comm: startpar Not tainted 3.16.0-rc3-00062-gd92a333-dirty #5
task: bb230b80 ti: bb256000 task.ti: bb256000
PC is at 0xfffffffe
LR is at iwmmxt_task_copy+0x44/0x4c
pc : [<fffffffe>]    lr : [<800130ac>]    psr: 40000033
sp : bb257de8  ip : 00000013  fp : bb257ea4
r10: bb256000  r9 : fffffdfe  r8 : 76e898e6
r7 : bb257ec8  r6 : bb256000  r5 : 7ea12760  r4 : 000000a0
r3 : ffffffff  r2 : 00000003  r1 : bb257df8  r0 : 00000000
Flags: nZcv  IRQs on  FIQs on  Mode SVC_32  ISA Thumb  Segment user
Control: 10c5387d  Table: 3b25c019  DAC: 00000015
Process startpar (pid: 62, stack limit = 0xbb256248)

This patch fixes the issue by moving concan_{save,dump,load} into separate
code sections and make iwmmxt_task_enable() call them in the same way the
other functions use concan_ symbols. The test for valid ownership is moved
to concan_save and is safe for the other user of it, iwmmxt_task_disable().
The register collision is also resolved by moving concan_ symbols as
{inc,dec}_preempt_count are now local to iwmmxt_task_enable().

Fixes: 431a84b1a4 ("ARM: 8034/1: Disable preemption in iwmmxt_task_enable()")

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 12:30:14 +01:00
Russell King 6ebbf2ce43 ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+
ARMv6 and greater introduced a new instruction ("bx") which can be used
to return from function calls.  Recent CPUs perform better when the
"bx lr" instruction is used rather than the "mov pc, lr" instruction,
and this sequence is strongly recommended to be used by the ARM
architecture manual (section A.4.1.1).

We provide a new macro "ret" with all its variants for the condition
code which will resolve to the appropriate instruction.

Rather than doing this piecemeal, and miss some instances, change all
the "mov pc" instances to use the new macro, with the exception of
the "movs" instruction and the kprobes code.  This allows us to detect
the "mov pc, lr" case and fix it up - and also gives us the possibility
of deploying this for other registers depending on the CPU selection.

Reported-by: Will Deacon <will.deacon@arm.com>
Tested-by: Stephen Warren <swarren@nvidia.com> # Tegra Jetson TK1
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr> # mioa701_bootresume.S
Tested-by: Andrew Lunn <andrew@lunn.ch> # Kirkwood
Tested-by: Shawn Guo <shawn.guo@freescale.com>
Tested-by: Tony Lindgren <tony@atomide.com> # OMAPs
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com> # Armada XP, 375, 385
Acked-by: Sekhar Nori <nsekhar@ti.com> # DaVinci
Acked-by: Christoffer Dall <christoffer.dall@linaro.org> # kvm/hyp
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com> # PXA3xx
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> # Xen
Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # ARMv7M
Tested-by: Simon Horman <horms+renesas@verge.net.au> # Shmobile
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 12:29:04 +01:00
Russell King 1fb333489f Merge branches 'alignment', 'fixes', 'l2c' (early part) and 'misc' into for-next 2014-06-05 12:35:52 +01:00
Sebastian Hesselbarth c2f07fe64d ARM: 8038/1: iwmmxt: explicitly check for supported architectures
iwmmxt.S requires special treatment of coprocessor access registers
for PJ4 and XScale-based CPUs. It only checks for CPU_PJ4 and drops
down to XScale-based treatment on all other architectures.

As some PJ4B also come with iWMMXt and also need PJ4 treatment,
rework the corresponding preprocessor directives to explicitly
check for supported architectures and fail on unsupported ones.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-04-25 12:07:32 +01:00
Catalin Marinas 1417a6b8dc ARM: 8036/1: Enable IRQs before attempting to read user space in __und_usr
The Undef abort handler in the kernel reads the undefined instruction
from user space. If the page table was modified from another CPU, the
user access could fail and do_page_fault() will be executed with
interrupts disabled. This can potentially deadlock on ARM11MPCore or on
Cortex-A15 with erratum 798181 workaround enabled (both implying IPI for
TLB maintenance with page table lock held).

This patch enables the IRQs in __und_usr before attempting to read the
instruction from user space.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Arun KS <getarunks@gmail.com>
Cc: Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ryan Mallon <rmallon@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-04-25 12:06:38 +01:00
Catalin Marinas 431a84b1a4 ARM: 8034/1: Disable preemption in iwmmxt_task_enable()
This patch is in preparation for calling the iwmmxt_task_enable()
function with interrupts enabled.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-04-25 12:06:37 +01:00
Lennert Buytenhek 392ba787bc ARM: pxa: fix logic error in PJ4 iWMMXt handling
This got added in:

	commit ef6c84454f
	Author: Haojian Zhuang <haojian.zhuang@marvell.com>
	Date:   Wed Nov 24 11:54:25 2010 +0800

	    ARM: pxa: add iwmmx support for PJ4

which does:

-       mrc     p15, 0, r2, c15, c1, 0
-       orr     r2, r2, #0x3                    @ enable access to CP0 and CP1
-       mcr     p15, 0, r2, c15, c1, 0
+       @ enable access to CP0 and CP1
+       XSC(mrc p15, 0, r2, c15, c1, 0)
+       XSC(orr r2, r2, #0x3)
+       XSC(mcr p15, 0, r2, c15, c1, 0)

but then later does:

-       mrc     p15, 0, r4, c15, c1, 0
-       orr     r4, r4, #0x3                    @ enable access to CP0 and CP1
-       mcr     p15, 0, r4, c15, c1, 0
+       @ enable access to CP0 and CP1
+       XSC(mrc p15, 0, r4, c15, c1, 0)
+       XSC(orr r4, r4, #0xf)
+       XSC(mcr p15, 0, r4, c15, c1, 0)

Signed-off-by: Lennert Buytenhek <buytenh@laptop.org>
Acked-by Haojian <haojian.zhuang@gmail.com>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
2011-08-11 10:10:26 +08:00
Haojian Zhuang ef6c84454f ARM: pxa: add iwmmx support for PJ4
iwmmxt is used in XScale, XScale3, Mohawk and PJ4 core. But the instructions
of accessing CP0 and CP1 is changed in PJ4. Append more files to support
iwmmxt in PJ4 core.

Signed-off-by: Zhou Zhu <zzhu3@marvell.com>
Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
2010-12-20 23:07:36 +08:00
Lennert Buytenhek ae95bfbb2b [ARM] 3707/1: iwmmxt: use the generic thread notifier infrastructure
Patch from Lennert Buytenhek

This patch makes the iWMMXt context switch hook use the generic
thread notifier infrastructure that was recently merged in commit
d6551e884c.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-07-01 19:56:48 +01:00
Lennert Buytenhek 3da4bd2bfc [ARM] 3632/1: iwmmxt: fix up argument comment for iwmmxt_task_restore()
Patch from Lennert Buytenhek

Commit d6551e884c forgot to update the
description of what goes into r2 when calling iwmmxt_task_restore().

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-24 09:57:13 +01:00
Russell King d6551e884c [ARM] Add thread_notify infrastructure
Some machine classes need to allow VFP support to be built into the
kernel, but still allow the kernel to run even though VFP isn't
present.  Unfortunately, the kernel hard-codes VFP instructions
into the thread switch, which prevents this being run-time selectable.

Solve this by introducing a notifier which things such as VFP can
hook into to be informed of events which affect the VFP subsystem
(eg, creation and destruction of threads, switches between threads.)

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-22 10:24:18 +01:00
Sam Ravnborg e6ae744dd2 kbuild: arm - use generic asm-offsets.h support
Delete obsoleted stuff from arch Makefile and rename
constants.h to asm-offsets.h

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-09-09 21:08:59 +02:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00