Instead of using of_graph_get_port_by_id() to get the port and then
of_get_child_by_name() to get the first endpoint, get to the endpoint
in a single step.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Instead of using of_graph_get_port_by_id() to get the port and then
of_get_child_by_name() to get the first endpoint, get to the endpoint
in a single step.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Document the ddc-i2c-bus property used by imx-ldb driver to read EDID
information via I2C interface.
Signed-off-by: Akshay Bhat <akshay.bhat@timesys.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Add support for reading EDID over Display Data Channel. If no DDC
adapter is available, falls back to hardcoded EDID or display-timings
node as before.
Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
Signed-off-by: Akshay Bhat <akshay.bhat@timesys.com>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
l2tp_ip6 tunnel and session lookups were still using init_net, although
the l2tp core infrastructure already supports lookups keyed by 'net'.
As a result, l2tp_ip6_recv discarded packets for tunnels/sessions
created in namespaces other than the init_net.
Fix, by using dev_net(skb->dev) or sock_net(sk) where appropriate.
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Clarify how secure_redirects works. Mention that RFC1122 always applies.
Signed-off-by: Eric Garver <e@erig.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix a logic error to avoid potential null pointer dereference.
Signed-off-by: Baozeng Ding <sploving1@gmail.com>
Reviewed-by: Stefan Schmidt<stefan@osg.samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since NAPI works by shutting down event interrupts when theres
work and turning them on when theres none, the net driver must
make sure that interrupts are disabled when it reschedules polling.
By calling napi_reschedule, the driver switches to polling mode,
therefor there should be no interrupt interference.
Any received packets will be handled in nps_enet_poll by polling the HW
indication of received packet until all packets are handled.
Signed-off-by: Elad Kanfi <eladkan@mellanox.com>
Acked-by: Noam Camus <noamca@mellanox.com>
Tested-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use %*ph specifier to dump small buffers in hex format instead doing this
byte-by-byte.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If we pass ERR_PTR(-EFAULT) to kfree() then it's going to oops.
Fixes: 2ece068e1b ('ptp: use memdup_user().')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A previous patch added the fou6.ko module, but that failed to link
in a couple of configurations:
net/built-in.o: In function `ip6_tnl_encap_add_fou_ops':
net/ipv6/fou6.c:88: undefined reference to `ip6_tnl_encap_add_ops'
net/ipv6/fou6.c:94: undefined reference to `ip6_tnl_encap_add_ops'
net/ipv6/fou6.c:97: undefined reference to `ip6_tnl_encap_del_ops'
net/built-in.o: In function `ip6_tnl_encap_del_fou_ops':
net/ipv6/fou6.c:106: undefined reference to `ip6_tnl_encap_del_ops'
net/ipv6/fou6.c:107: undefined reference to `ip6_tnl_encap_del_ops'
If CONFIG_IPV6=m, ip6_tnl_encap_add_ops/ip6_tnl_encap_del_ops
are in a module, but fou6.c can still be built-in, and that
obviously fails to link.
Also, if CONFIG_IPV6=y, but CONFIG_IPV6_TUNNEL=m or
CONFIG_IPV6_TUNNEL=n, the same problem happens for a different
reason.
This adds two new silent Kconfig symbols to work around both
problems:
- CONFIG_IPV6_FOU is now always set to 'm' if either CONFIG_NET_FOU=m
or CONFIG_IPV6=m
- CONFIG_IPV6_FOU_TUNNEL is set implicitly when IPV6_FOU is enabled
and NET_FOU_IP_TUNNELS is also turned out, and it will ensure
that CONFIG_IPV6_TUNNEL is also available.
The options could be made user-visible as well, to give additional
room for configuration, but it seems easier not to bother users
with more choice here.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: aa3463d65e ("fou: Add encap ops for IPv6 tunnels")
Signed-off-by: David S. Miller <davem@davemloft.net>
A recent cleanup moved MAX_IPTUN_ENCAP_OPS along with some other
definitions, but it is now invisible when CONFIG_INET is
not defined, but still referenced from ip6_tunnel.h:
In file included from net/xfrm/xfrm_input.c:17:0:
include/net/ip6_tunnel.h:67:17: error: 'MAX_IPTUN_ENCAP_OPS' undeclared here (not in a function)
ip6tun_encaps[MAX_IPTUN_ENCAP_OPS];
^~~~~~~~~~~~~~~~~~~
This hides the ip6_encap_hlen and ip6_tnl_encap functions inside
of CONFIG_INET so we don't run into the the problem.
Alternatively we could move the macro out of the #ifdef again to
restore the previous behavior
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 55c2bc1432 ("net: Cleanup encap items in ip_tunnels.h")
Signed-off-by: David S. Miller <davem@davemloft.net>
The RTAS calls "ibm,configure-pe" and "ibm,configure-bridge" perform the
same actions, however the former can skip configuration if unnecessary.
The existing code treats them as different tokens even though only one
will ever be called. Refactor this by making a single token that is
assigned during init.
Signed-off-by: Russell Currey <ruscur@russell.cc>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
In the "ibm,configure-pe" and "ibm,configure-bridge" RTAS calls, the
spec states that values of 9900-9905 can be returned, indicating that
software should delay for 10^x (where x is the last digit, i.e. 990x)
milliseconds and attempt the call again. Currently, the kernel doesn't
know about this, and respecting it fixes some PCI failures when the
hypervisor is busy.
The delay is capped at 0.2 seconds.
Cc: <stable@vger.kernel.org> # 3.10+
Signed-off-by: Russell Currey <ruscur@russell.cc>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We must handle data access exception as well as memory address unaligned
exceptions from return from trap window fill faults, not just normal
TLB misses.
Otherwise we can get an OOPS that looks like this:
ld-linux.so.2(36808): Kernel bad sw trap 5 [#1]
CPU: 1 PID: 36808 Comm: ld-linux.so.2 Not tainted 4.6.0 #34
task: fff8000303be5c60 ti: fff8000301344000 task.ti: fff8000301344000
TSTATE: 0000004410001601 TPC: 0000000000a1a784 TNPC: 0000000000a1a788 Y: 00000002 Not tainted
TPC: <do_sparc64_fault+0x5c4/0x700>
g0: fff8000024fc8248 g1: 0000000000db04dc g2: 0000000000000000 g3: 0000000000000001
g4: fff8000303be5c60 g5: fff800030e672000 g6: fff8000301344000 g7: 0000000000000001
o0: 0000000000b95ee8 o1: 000000000000012b o2: 0000000000000000 o3: 0000000200b9b358
o4: 0000000000000000 o5: fff8000301344040 sp: fff80003013475c1 ret_pc: 0000000000a1a77c
RPC: <do_sparc64_fault+0x5bc/0x700>
l0: 00000000000007ff l1: 0000000000000000 l2: 000000000000005f l3: 0000000000000000
l4: fff8000301347e98 l5: fff8000024ff3060 l6: 0000000000000000 l7: 0000000000000000
i0: fff8000301347f60 i1: 0000000000102400 i2: 0000000000000000 i3: 0000000000000000
i4: 0000000000000000 i5: 0000000000000000 i6: fff80003013476a1 i7: 0000000000404d4c
I7: <user_rtt_fill_fixup+0x6c/0x7c>
Call Trace:
[0000000000404d4c] user_rtt_fill_fixup+0x6c/0x7c
The window trap handlers are slightly clever, the trap table entries for them are
composed of two pieces of code. First comes the code that actually performs
the window fill or spill trap handling, and then there are three instructions at
the end which are for exception processing.
The userland register window fill handler is:
add %sp, STACK_BIAS + 0x00, %g1; \
ldxa [%g1 + %g0] ASI, %l0; \
mov 0x08, %g2; \
mov 0x10, %g3; \
ldxa [%g1 + %g2] ASI, %l1; \
mov 0x18, %g5; \
ldxa [%g1 + %g3] ASI, %l2; \
ldxa [%g1 + %g5] ASI, %l3; \
add %g1, 0x20, %g1; \
ldxa [%g1 + %g0] ASI, %l4; \
ldxa [%g1 + %g2] ASI, %l5; \
ldxa [%g1 + %g3] ASI, %l6; \
ldxa [%g1 + %g5] ASI, %l7; \
add %g1, 0x20, %g1; \
ldxa [%g1 + %g0] ASI, %i0; \
ldxa [%g1 + %g2] ASI, %i1; \
ldxa [%g1 + %g3] ASI, %i2; \
ldxa [%g1 + %g5] ASI, %i3; \
add %g1, 0x20, %g1; \
ldxa [%g1 + %g0] ASI, %i4; \
ldxa [%g1 + %g2] ASI, %i5; \
ldxa [%g1 + %g3] ASI, %i6; \
ldxa [%g1 + %g5] ASI, %i7; \
restored; \
retry; nop; nop; nop; nop; \
b,a,pt %xcc, fill_fixup_dax; \
b,a,pt %xcc, fill_fixup_mna; \
b,a,pt %xcc, fill_fixup;
And the way this works is that if any of those memory accesses
generate an exception, the exception handler can revector to one of
those final three branch instructions depending upon which kind of
exception the memory access took. In this way, the fault handler
doesn't have to know if it was a spill or a fill that it's handling
the fault for. It just always branches to the last instruction in
the parent trap's handler.
For example, for a regular fault, the code goes:
winfix_trampoline:
rdpr %tpc, %g3
or %g3, 0x7c, %g3
wrpr %g3, %tnpc
done
All window trap handlers are 0x80 aligned, so if we "or" 0x7c into the
trap time program counter, we'll get that final instruction in the
trap handler.
On return from trap, we have to pull the register window in but we do
this by hand instead of just executing a "restore" instruction for
several reasons. The largest being that from Niagara and onward we
simply don't have enough levels in the trap stack to fully resolve all
possible exception cases of a window fault when we are already at
trap level 1 (which we enter to get ready to return from the original
trap).
This is executed inline via the FILL_*_RTRAP handlers. rtrap_64.S's
code branches directly to these to do the window fill by hand if
necessary. Now if you look at them, we'll see at the end:
ba,a,pt %xcc, user_rtt_fill_fixup;
ba,a,pt %xcc, user_rtt_fill_fixup;
ba,a,pt %xcc, user_rtt_fill_fixup;
And oops, all three cases are handled like a fault.
This doesn't work because each of these trap types (data access
exception, memory address unaligned, and faults) store their auxiliary
info in different registers to pass on to the C handler which does the
real work.
So in the case where the stack was unaligned, the unaligned trap
handler sets up the arg registers one way, and then we branched to
the fault handler which expects them setup another way.
So the FAULT_TYPE_* value ends up basically being garbage, and
randomly would generate the backtrace seen above.
Reported-by: Nick Alcock <nix@esperi.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a set of four fixes noticed in the merge window. The aacraid
one is an optimisation, the mp3sas one fixes a spurious printk, the
sd_check_events one fixes a theoretical race and the failed zero
length commands fixes a bug in our completion/retry routines that has
been causing problems in the field.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
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Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"This is a set of four fixes noticed in the merge window. The aacraid
one is an optimisation, the mp3sas one fixes a spurious printk, the
sd_check_events one fixes a theoretical race and the failed zero
length commands fixes a bug in our completion/retry routines that has
been causing problems in the field"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
aacraid: do not activate events on non-SRC adapters
mpt3sas: add missing curly braces
sd: get disk reference in sd_check_events()
scsi_lib: correctly retry failed zero length REQ_TYPE_FS commands
This makes it possible to distinguish between iio devices with the same
name.
Signed-off-by: Crestez Dan Leonard <leonard.crestez@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This will clean (disable buffer/trigger/channels) when doing
something like a CTRL-C. Otherwise restarting generic_buffer requires a
manual echo 0 > buffer/enable
This also cleanup up all the code freeing string buffers at
the end of main. We initialize all pointers to NULL so that cleanup can
all be done under a single error label.
Signed-off-by: Crestez Dan Leonard <leonard.crestez@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
MODULE_ALIAS isn't needed since the module name is the same as the alias
defined.
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
bmc150 driver supports also BMC156 and BMM150 chips.
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This makes it clear that generic_buffer is an IIO tool
and also complies with filename conventions in tools/iio.
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Add options to the Makefile for install/uninstall similar to other tools.
Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Replace the code that guarantees the device stays in direct mode
with iio_device_claim_direct_mode() which does same.
Signed-off-by: Alison Schofield <amsfield22@gmail.com>
Acked-by: Daniel Baluta <daniel.baluta@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Replace the code that guarantees the device stays in direct mode
with iio_device_claim_direct_mode() which does same.
Signed-off-by: Alison Schofield <amsfield22@gmail.com>
Acked-by: Daniel Baluta <daniel.baluta@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Replace the code that guarantees the device stays in direct mode
with iio_device_claim_direct_mode() which does same.
Signed-off-by: Alison Schofield <amsfield22@gmail.com>
Acked-by: Daniel Baluta <daniel.baluta@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Replace the code that guarantees the device stays in direct mode
with iio_device_claim_direct_mode() which does same.
Signed-off-by: Alison Schofield <amsfield22@gmail.com>
Acked-by: Daniel Baluta <daniel.baluta@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
All signal frames must be at least 16-byte aligned, because that is
the alignment we explicitly create when we build signal return stack
frames.
All stack pointers must be at least 8-byte aligned.
Signed-off-by: David S. Miller <davem@davemloft.net>
Driver was checking for direct mode but not locking it down.
Use iio_device_claim_direct_mode() to guarantee device stays
in direct mode.
Signed-off-by: Alison Schofield <amsfield22@gmail.com>
Acked-by: Daniel Baluta <daniel.baluta@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Ensure failure to enable power regulators is properly handled.
Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Use SMBus "block read" protocol only when supported by adapter.
Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Remove st_sensors_get_buffer_element symbol export since not explicitly
used outside of st_sensors driver.
Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
The self-test was updated to cover zero-length strings; the function
needs to be updated, too.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Fixes: fcfd2fbf22 ("fs/namei.c: Add hashlen_string() function")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Initial support for ST LPS22HB pressure sensor. Datasheet:
http://www2.st.com/resource/en/datasheet/lps22hb.pdf
Features:
* pressure data and timestamping channels
* sampling frequency selection
* interrupt based trigger
* over I2C or SPI
Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This structure has not been optional for a long time (if ever) but the
code implies that it is. As we then use it later in a fashion that would
crash if it was in fact NULL, it's inconsistent so fix it up by removing
unnecessary checks.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
The original name was simply hash_string(), but that conflicted with a
function with that name in drivers/base/power/trace.c, and I decided
that calling it "hashlen_" was better anyway.
But you have to do it in two places.
[ This caused build errors for architectures that don't define
CONFIG_DCACHE_WORD_ACCESS - Linus ]
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Fixes: fcfd2fbf22 ("fs/namei.c: Add hashlen_string() function")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The HPFS filesystem used generic_show_options to produce string that is
displayed in /proc/mounts. However, there is a problem that the options
may disappear after remount. If we mount the filesystem with option1
and then remount it with option2, /proc/mounts should show both option1
and option2, however it only shows option2 because the whole option
string is replaced with replace_mount_options in hpfs_remount_fs.
To fix this bug, implement the hpfs_show_options function that prints
options that are currently selected.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit c8f33d0bec ("affs: kstrdup() memory handling") checks if the
kstrdup function returns NULL due to out-of-memory condition.
However, if we are remounting a filesystem with no change to
filesystem-specific options, the parameter data is NULL. In this case,
kstrdup returns NULL (because it was passed NULL parameter), although no
out of memory condition exists. The mount syscall then fails with
ENOMEM.
This patch fixes the bug. We fail with ENOMEM only if data is non-NULL.
The patch also changes the call to replace_mount_options - if we didn't
pass any filesystem-specific options, we don't call
replace_mount_options (thus we don't erase existing reported options).
Fixes: c8f33d0bec ("affs: kstrdup() memory handling")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit ce657611ba ("hpfs: kstrdup() out of memory handling") checks if
the kstrdup function returns NULL due to out-of-memory condition.
However, if we are remounting a filesystem with no change to
filesystem-specific options, the parameter data is NULL. In this case,
kstrdup returns NULL (because it was passed NULL parameter), although no
out of memory condition exists. The mount syscall then fails with
ENOMEM.
This patch fixes the bug. We fail with ENOMEM only if data is non-NULL.
The patch also changes the call to replace_mount_options - if we didn't
pass any filesystem-specific options, we don't call
replace_mount_options (thus we don't erase existing reported options).
Fixes: ce657611ba ("hpfs: kstrdup() out of memory handling")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Various builds (such as i386:allmodconfig) fail with
fs/binfmt_aout.c:133:2: error: expected identifier or '(' before 'return'
fs/binfmt_aout.c:134:1: error: expected identifier or '(' before '}' token
[ Oops. My bad, I had stupidly thought that "allmodconfig" covered this
on x86-64 too, but it obviously doesn't. Egg on my face. - Linus ]
Fixes: 5d22fc25d4 ("mm: remove more IS_ERR_VALUE abuses")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull string hash improvements from George Spelvin:
"This series does several related things:
- Makes the dcache hash (fs/namei.c) useful for general kernel use.
(Thanks to Bruce for noticing the zero-length corner case)
- Converts the string hashes in <linux/sunrpc/svcauth.h> to use the
above.
- Avoids 64-bit multiplies in hash_64() on 32-bit platforms. Two
32-bit multiplies will do well enough.
- Rids the world of the bad hash multipliers in hash_32.
This finishes the job started in commit 689de1d6ca ("Minimal
fix-up of bad hashing behavior of hash_64()")
The vast majority of Linux architectures have hardware support for
32x32-bit multiply and so derive no benefit from "simplified"
multipliers.
The few processors that do not (68000, h8/300 and some models of
Microblaze) have arch-specific implementations added. Those
patches are last in the series.
- Overhauls the dcache hash mixing.
The patch in commit 0fed3ac866 ("namei: Improve hash mixing if
CONFIG_DCACHE_WORD_ACCESS") was an off-the-cuff suggestion.
Replaced with a much more careful design that's simultaneously
faster and better. (My own invention, as there was noting suitable
in the literature I could find. Comments welcome!)
- Modify the hash_name() loop to skip the initial HASH_MIX(). This
would let us salt the hash if we ever wanted to.
- Sort out partial_name_hash().
The hash function is declared as using a long state, even though
it's truncated to 32 bits at the end and the extra internal state
contributes nothing to the result. And some callers do odd things:
- fs/hfs/string.c only allocates 32 bits of state
- fs/hfsplus/unicode.c uses it to hash 16-bit unicode symbols not bytes
- Modify bytemask_from_count to handle inputs of 1..sizeof(long)
rather than 0..sizeof(long)-1. This would simplify users other
than full_name_hash"
Special thanks to Bruce Fields for testing and finding bugs in v1. (I
learned some humbling lessons about "obviously correct" code.)
On the arch-specific front, the m68k assembly has been tested in a
standalone test harness, I've been in contact with the Microblaze
maintainers who mostly don't care, as the hardware multiplier is never
omitted in real-world applications, and I haven't heard anything from
the H8/300 world"
* 'hash' of git://ftp.sciencehorizons.net/linux:
h8300: Add <asm/hash.h>
microblaze: Add <asm/hash.h>
m68k: Add <asm/hash.h>
<linux/hash.h>: Add support for architecture-specific functions
fs/namei.c: Improve dcache hash function
Eliminate bad hash multipliers from hash_32() and hash_64()
Change hash_64() return value to 32 bits
<linux/sunrpc/svcauth.h>: Define hash_str() in terms of hashlen_string()
fs/namei.c: Add hashlen_string() function
Pull out string hash to <linux/stringhash.h>
This will improve the performance of hash_32() and hash_64(), but due
to complete lack of multi-bit shift instructions on H8, performance will
still be bad in surrounding code.
Designing H8-specific hash algorithms to work around that is a separate
project. (But if the maintainers would like to get in touch...)
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: uclinux-h8-devel@lists.sourceforge.jp
Microblaze is an FPGA soft core that can be configured various ways.
If it is configured without a multiplier, the standard __hash_32()
will require a call to __mulsi3, which is a slow software loop.
Instead, use a shift-and-add sequence for the constant multiply.
GCC knows how to do this, but it's not as clever as some.
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Cc: Alistair Francis <alistair.francis@xilinx.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Philipp Zabel