Current driver assumes that child node channel name is either
"xlnx,axi-vdma-mm2s-channel" or "xlnx,axi-vdma-s2mm-channel"
which is confusing the users of AXI DMA and CDMA.
This patch fixes this issue by using different channel
names for the AXI DMA and AXI CDMA child nodes.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
In the existing vdma driver support for
AXI DMA and CDMA got added so the driver is no
longer VDMA specific.
This patch renames the driver and DT binding doc to xilinx_dma
and updates the Kconfig description for all the DMAS.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The AXI DMA support is added to the existing AXI VDMA
driver. Device tree binding information also updated
in the VDMA binding doc.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This patch adds support for AXI DMA multi-channel dma mode
Multichannel mode enables DMA to connect to multiple masters
and slaves on the streaming side.
In Multichannel mode AXI DMA supports 2D transfers.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The bam_dma driver gained runtime PM support, but that causes build
warnings whenever CONFIG_PM is disabled:
drivers/dma/qcom/bam_dma.c:1324:12: error: 'bam_dma_runtime_resume' defined but not used [-Werror=unused-function]
static int bam_dma_runtime_resume(struct device *dev)
^~~~~~~~~~~~~~~~~~~~~~
drivers/dma/qcom/bam_dma.c:1315:12: error: 'bam_dma_runtime_suspend' defined but not used [-Werror=unused-function]
static int bam_dma_runtime_suspend(struct device *dev)
This removes the incomplete #ifdef guard and instead marks all
four PM functions as __maybe_unused, which avoids this kind of
warning.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 7d2545599f ("dmaengine: qcom-bam-dma: Add pm_runtime support")
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
When building this driver on arm64, we get a harmless type
mismatch warning:
drivers/dma/bcm2835-dma.c: In function 'bcm2835_dma_fill_cb_chain_with_sg':
include/linux/kernel.h:743:17: warning: comparison of distinct pointer types lacks a cast
(void) (&_min1 == &_min2); \
^
drivers/dma/bcm2835-dma.c:409:21: note: in expansion of macro 'min'
cb->cb->length = min(len, max_len);
This changes the type of the 'len' variable to size_t, which
avoids the problem.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 388cc7a281 ("dmaengine: bcm2835: add slave_sg support to bcm2835-dma")
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Return IRQ_NONE in the interrupt handler when it is called but no IRQs are
pending. This allows the system to recover in case of an interrupt storm
e.g. due to a wrong interrupt configuration setup.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Propagate errors returned by platform_get_irq() to the driver core. This
will enable proper probe deferring for the driver in case the IRQ provider
has not been registered yet.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Add MODULE_DEVICE_TABLE() for the axi-dmac driver. This allows the driver
to be loaded on demand when built as a module.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
When building this driver on arm64, we get a harmless type
mismatch warning:
drivers/dma/bcm2835-dma.c: In function 'bcm2835_dma_fill_cb_chain_with_sg':
include/linux/kernel.h:743:17: warning: comparison of distinct pointer types lacks a cast
(void) (&_min1 == &_min2); \
^
drivers/dma/bcm2835-dma.c:409:21: note: in expansion of macro 'min'
cb->cb->length = min(len, max_len);
This changes the type of the 'len' variable to size_t, which
avoids the problem.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 388cc7a281 ("dmaengine: bcm2835: add slave_sg support to bcm2835-dma")
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Adds pm_runtime support for BAM DMA so that clock is enabled only
when there is a transaction going on to help save power.
Signed-off-by: Pramod Gurav <pramod.gurav@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Commit 71f7e6cc55 ('dmaengine: tegra20-apb-dma: Only calculate residue
if txstate exists') changed the tegra_dma_tx_status() function to only
calculate the residue if there is a valid 'txstate' pointer for storing
the residue. Although this makes sense, this changed the behaviour of
the function tegra_dma_tx_status() such that if the pointer 'txstate' is
not valid, then we will return whatever state is returned by
dma_cookie_status() and no longer return the state by looking up the DMA
descriptor and returning it's state.
Please note that dma_cookie_status() will either return DMA_COMPLETE or
DMA_IN_PROGRESS. However, if dma_cookie_status() returns DMA_IN_PROGRESS
the actual status could be DMA_ERROR which will only be seen from
checking the descriptor status. Therefore, even if 'txstate' is not
valid, still check to see if there is a valid descriptor for the cookie
in question and if so return the descriptor state. Finally, ensure the
residue is still not calculated if the 'txstate' is not valid.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The calculation of the DMA residue for the Tegra APB DMA is duplicated
in two places in the tegra_dma_tx_status() function. Remove this
duplicated code by moving calculation to the end of the function and
only calculating if we found a valid descriptor.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Correct the grammar in the debug message when no descriptor is found.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
mbr_ds is an integer, don't use %pad to print it.
Fixes: commit 268914f4e7 ("dmaengine: at_xdmac: use %pad format string for dma_addr_t")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The omap_dmaxbar_init() function is not exported or declared outside
the driver, so make it static to fix the following sparse warning:
drivers/dma/ti-dma-crossbar.c:455:5: warning: symbol 'omap_dmaxbar_init' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
If kzalloc() fails it will issue it's own error message including
a dump_stack(). So remove the site specific error messages.
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
There is no point calculating the residue if there is
no txstate to store the value.
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
There is no point in calculating the residue if state does not
exist to store the value.
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
There is no point calculating the residue if there is
no txstate to store the value.
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Doing so saves a few lines of code in the driver.
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
There is no point in calculating the residue if there is no
txstate to store the value.
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
It is useful to print the error code as part of the error
message.
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Currently fsl-edma doesn't clk_disable_unprepare()
its clocks on error conditions. This patch adds a
fsl_disable_clocks helper for this, and also only
disables clocks which were enabled if encountering
an error whilst enabling clocks.
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The AXI CDMA is a soft ip, which can be programmed to support
32 bit addressing or greater than 32 bit addressing.
When the AXI CDMA ip is configured for 32 bit address space
in simple dma mode the source/destination buffer address is
specified by a single register(18h for Source buffer address and
20h for Destination buffer address). When configured in SG mode
the current descriptor and tail descriptor are specified by a
Single register(08h for curdesc 10h for tail desc).
When the AXI CDMA core is configured for an address space greater
than 32 then each buffer address or descriptor address is specified by
a combination of two registers.
The first register specifies the LSB 32 bits of address,
while the next register specifies the MSB 32 bits of address.
For example, 08h will specify the LSB 32 bits while 0Ch will
specify the MSB 32 bits of the first start address.
So we need to program two registers at a time.
This patch adds the 64 bit addressing support to the axicdma
IP in the driver.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The AXI DMA is a soft ip, which can be programmed to support
32 bit addressing or greater than 32 bit addressing.
When the AXI DMA ip is configured for 32 bit address space
in simple dma mode the buffer address is specified by a single register
(18h for MM2S channel and 48h for S2MM channel). When configured in SG mode
The current descriptor and tail descriptor are specified by a single
Register(08h for curdesc 10h for tail desc for MM2S channel and 38h for
Curdesc and 40h for tail desc for S2MM).
When the AXI DMA core is configured for an address space greater
than 32 then each buffer address or descriptor address is specified by
a combination of two registers.
The first register specifies the LSB 32 bits of address,
while the next register specifies the MSB 32 bits of address.
For example, 48h will specify the LSB 32 bits while 4Ch will
specify the MSB 32 bits of the first start address.
So we need to program two registers at a time.
This patch adds the 64 bit addressing support for the axidma
IP in the driver.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
There are some places where whitespace is used in very funky ways. Fix
the most serious ones to make the code easier on the eye.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The newly added xilinx_dma_prep_dma_cyclic function sometimes causes
a gcc warning about the use of the segment function in case
we never run into the inner loop of the function:
dma/xilinx/xilinx_vdma.c: In function 'xilinx_dma_prep_dma_cyclic':
dma/xilinx/xilinx_vdma.c:1808:23: error: 'segment' may be used uninitialized in this function [-Werror=maybe-uninitialized]
segment->hw.control |= XILINX_DMA_BD_SOP;
This can only happen if the period len is zero (which would cause other
problems earlier), or if the buffer is shorter than a period. Neither
of them should ever happen, but by adding an explicit check for these two
cases, we can abort in a more controlled way, and the compiler is
able to see that we never use uninitialized data.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This patch fixes the below compilation warining.
drivers/dma/xilinx/xilinx_vdma.c: In function 'xilinx_dma_prep_dma_cyclic':
drivers/dma/xilinx/xilinx_vdma.c:1808:23: warning: 'segment' may be used
uninitialized in this function [-Wmaybe-uninitialized]
segment->hw.control |= XILINX_DMA_BD_SOP;
The start of packet (SOP) should be set to the first segment in the desc
chain not for the last segment of the desc chain.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The bcm2835_dma_prep_dma_memcpy() function is not exported
outside the driver, so make it static to avoid the following
warning:
drivers/dma/bcm2835-dma.c:616:32: warning: symbol 'bcm2835_dma_prep_dma_memcpy' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The at_xdmac_init_used_desc() and at_xdmac_prep_dma_memset()
functions are not exported outside the driver, so make them
static to avoid the following warnings:
drivers/dma/at_xdmac.c:459:6: warning: symbol 'at_xdmac_init_used_desc' was not declared. Should it be static?
drivers/dma/at_xdmac.c:1205:32: warning: symbol 'at_xdmac_prep_dma_memset' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The sirfsoc_dmadata structs are not used outside the driver, so
remove build warnings by making them static. Fixes:
drivers/dma/sirf-dma.c:1129:24: warning: symbol 'sirfsoc_dmadata_a6' was not declared. Should it be static?
drivers/dma/sirf-dma.c:1134:24: warning: symbol 'sirfsoc_dmadata_a7v1' was not declared. Should it be static?
drivers/dma/sirf-dma.c:1139:24: warning: symbol 'sirfsoc_dmadata_a7v2' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Fix warning due to d40_width_to_bits() not being used outside
this file. Fixes:
drivers/dma/ste_dma40_ll.c:13:4: warning: symbol 'd40_width_to_bits' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The driver limits the physical number of paRAM slots to be used by channels.
If the transfer needs more slots (more SGs) then the transfer is broken up
to smaller chunks. When the chunk is finished the driver will rewrite the
physical slots and continues the transfer. This set up time can take some
time and we might miss DMA events. If the intermediate set completion is
using early completion (the interrupt will happen when the last slot is
issued to the TPTC and not when the transfer is finished by the TPTC) we
will have a bit more time to update the paRAM slots and less likely to have
missed events.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Remove the space before the "err_free_dma:" label in mv_xor_channel_add().
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Marcin Wojtas <mw@semihalf.com>
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
dma_pool_zalloc combines dma_pool_alloc and memset 0
this patch updates the driver to use dma_pool_zalloc.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This patch adds support for AXI DMA cyclic dma mode.
In cyclic mode, DMA fetches and processes the same
BDs without interruption. The DMA continues to fetch and process
until it is stopped or reset.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
For each descriptor, in addition to the memory used by the descriptors
structure itself, the driver allocates a list of chunks as well as a
buffer for hardware descriptors. Descriptors themselves are preallocated,
and allocation of the chunks and buffer is performed the first time the
descriptor is used. The memory isn't freed when the transfer is completed,
as the chunks and buffer will be needed again when the descriptor is
reused internally, so the driver keeps the memory around.
If only a few descriptors are used concurrently, the current
list_add_tail() implementation will result in all preallocated descriptors
being used before going back to the first one, and will thus allocate
chunks and a buffer for all preallocated descriptors. Using list_add()
will put the complete descriptor at the head of the list of available
descriptors, so the next transfer will be more likely to reuse a
descriptor that already has associated memory instead of one that has
never been used before.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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>
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>