Patch from George G. Davis
This patch is required for kernel XIP support on ARMv6 machines. It ensures that the access permission bits for kernel XIP section descriptors are APX=1 and AP[1:0]=01, which is Kernel read-only/User no access permissions. Prior to this change, kernel XIP section descriptor access permissions were set to Kernel no access/User no access on ARMv6 machines and the kernel would therefore hang upon entry to userspace when set_fs(USER_DS) was executed.
Signed-off-by: Steve Longerbeam
Signed-off-by: George G. Davis
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Nicolas Pitre
This patch entirely reworks the kernel assistance for NPTL on ARM.
In particular this provides an efficient way to retrieve the TLS
value and perform atomic operations without any instruction emulation
nor special system call. This even allows for pre ARMv6 binaries to
be forward compatible with SMP systems without any penalty.
The problematic and performance critical operations are performed
through segment of kernel provided user code reachable from user space
at a fixed address in kernel memory. Those fixed entry points are
within the vector page so we basically get it for free as no extra
memory page is required and nothing else may be mapped at that
location anyway.
This is different from (but doesn't preclude) a full blown VDSO
implementation, however a VDSO would prevent some assembly tricks with
constants that allows for efficient branching to those code segments.
And since those code segments only use a few cycles before returning to
user code, the overhead of a VDSO far call would add a significant
overhead to such minimalistic operations.
The ARM_NR_set_tls syscall also changed number. This is done for two
reasons:
1) this patch changes the way the TLS value was previously meant to be
retrieved, therefore we ensure whatever library using the old way
gets fixed (they only exist in private tree at the moment since the
NPTL work is still progressing).
2) the previous number was allocated in a range causing an undefined
instruction trap on kernels not supporting that syscall and it was
determined that allocating it in a range returning -ENOSYS would be
much nicer for libraries trying to determine if the feature is
present or not.
Signed-off-by: Nicolas Pitre
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from George G. Davis
As noted in http://www.arm.com/linux/patch-2.6.9-arm1.gz, the "Faulty SWP instruction on 1136 doesn't set bit 11 in DFSR." So the v6_early_abort handler does not report the correct rd/wr direction for the SWP instruction which may result in SEGVS or hangs. In order to work around this problem, this patch merely updates the fix contained in the ARM Ltd. patch to use the macroised abort handler fixups.
Signed-off-by: George G. Davis
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
Assigning the address zero to a PCI device BAR causes some part of the
PCI subsystem to believe that resource allocation for that BAR failed
due to resource conflicts, which will make attempts to enable the
device fail. Work around this by assigning I/O addresses starting
from 00010000.
While we're at it, make the PCI I/O resource end at 0001ffff, since we
only have 64k of outbound I/O window on the IXP2000, and we don't do
bank switching.
Signed-off-by: Lennert Buytenhek
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
On the IXDP2800, the bootloader does an awful job of configuring
the PCI bus, so we make linux reconfigure everything. Having a 1:1
pci:phys address mapping generally simplifies everything, so try to
allocate PCI addresses from the [e0000000..ffffffff] range, which is
the physical address range of the outbound PCI window on the IXP2000.
This does not affect any of the other IXP2000 platforms since they
all use their bootloader's PCI resource assignment.
Signed-off-by: Lennert Buytenhek
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
Export ixp2000_pci_config_addr, to be used by the IXDP2800 platform
setup code to coordinate booting the master and slave NPU.
Signed-off-by: Lennert Buytenhek
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
SVC_MODE reflects the MODE_SVC definition in asm/ptrace.h. Use
the asm/ptrace.h definition instead, and remove SVC_MODE.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Patch from Jeff Lackey
This patch updates arch/arm/mach-pxa/sleep.S to support
the PXA270 CPU. It works around Errata 39 & 50 from the
Intel(R) PXA27x Processor Family Specification Update.
Signed-off-by: Jeff Lackey
Signed-off-by: Russell King
ARM define FIRST_USER_ADDRESS as PAGE_SIZE (beyond the machine vectors when
they are mapped low), and use that definition in place of locally defined
MIN_MAP_ADDR.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Convert ARM bitop assembly to a macro. All bitops follow the same
format, so it's silly duplicating the code when only one or two
instructions are different.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Fix show_regs() to provide a backtrace. Provide a new __show_regs()
function which implements the common subset of show_regs() and die().
Add prototypes to asm-arm/system.h
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
The footbridge ISA RTC was being initialised before we had setup the
kernel timer. This caused a divide by zero error when the current
time of day is set. Resolve this by initialising the RTC after
the kernel timer has been initialised.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
)
From: Russell King <rmk+lkml@arm.linux.org.uk>
Oddly, max_low_pfn/max_pfn end up being the number of pages in the system,
rather than the maximum PFN on ARM. This doesn't seem to cause any problems,
so just add a note about it.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
)
From: Russell King <rmk+lkml@arm.linux.org.uk>
For some reason, this help text was missed when the file was last audited
by the documentation referencing folk. Fix this incorrect documentation
reference.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
)
From: Russell King <rmk+lkml@arm.linux.org.uk>
ARM wasn't raising a SIGBUS with a siginfo structure. Fix
__do_user_fault() to allow us to use it for SIGBUS conditions, and arrange
for the sigbus path to use this.
We need to prevent the siginfo code being called if we do not have a user
space context to call it, so consolidate the "user_mode()" tests.
Thanks to Ian Campbell who spotted this oversight.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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!
