The SPI_MCR_PCSIS macro assumes that the controller has a number of chip
select signals equal to 6. That is not always the case, but actually is
described through the driver-specific "spi-num-chipselects" device tree
binding. LS1028A for example only has 4 chip selects.
Don't write to the upper bits of the PCSIS field, which are reserved in
the reference manual.
Fixes: 349ad66c0a ("spi:Add Freescale DSPI driver for Vybrid VF610 platform")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200318001603.9650-2-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This driver is not using any symbols from the GPIO .h files
so drop them.
It was however implicitly using <linux/pinctrl/consumer.h>
so include that instead.
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200317092457.264055-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The SPICC controller in Amlogic AXG & G12A is capable of driving the
CLK/MOSI/SS signal lines through the idle state which avoid the signals
floating in unexpected state, is capable of using linear clock divider
to reach a much fine tuned range of clocks, while the old controller only
uses a power of two clock divider, result at a more coarse clock range and
finally is capable of running at 80M clock.
The SPICC controller in Amlogic G12A takes the source clock from a specific
clock instead of the bus clock and has a different FIFO size and doesn't
handle the RX Half interrupt the same way as GXL & AXG variants. Thus
the burst management is simplified and takes in account a variable FIFO
size.
Now the controller can support frequencies higher than 30MHz, we need
the setup the I/O line delays in regard of the SPI clock frequency.
Neil Armstrong (7):
spi: meson-spicc: remove unused variables
spi: meson-spicc: support max 80MHz clock
spi: meson-spicc: add min sclk for each compatible
spi: meson-spicc: setup IO line delay
spi: meson-spicc: adapt burst handling for G12A support
dt-bindings: spi: amlogic,meson-gx-spicc: add Amlogic G12A compatible
spi: meson-spicc: add support for Amlogic G12A
Sunny Luo (2):
spi: meson-spicc: enhance output enable feature
spi: meson-spicc: add a linear clock divider support
.../bindings/spi/amlogic,meson-gx-spicc.yaml | 22 +
drivers/spi/Kconfig | 1 +
drivers/spi/spi-meson-spicc.c | 496 +++++++++++++-----
3 files changed, 392 insertions(+), 127 deletions(-)
--
2.22.0
_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.orghttp://lists.infradead.org/mailman/listinfo/linux-amlogic
to_spi_device() already checks 'dev'. No need to do it before calling
it.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://lore.kernel.org/r/20200312134507.10000-1-wsa@the-dreams.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Add support for the SPICC controllers on the Amlogic G12A SoCs family.
The G12A SPICC controllers inherit from the AXG enhanced registers but
takes an external pclk for the baud rate generator and can achieve up to
166MHz SCLK.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20200312133131.26430-10-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The G12A SPICC controller variant has a different FIFO size and doesn't
handle the RX Half interrupt the same way as GXL & AXG variants.
Thus simplify the burst management and take in account a variable FIFO
size.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20200312133131.26430-8-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Now the controller can support frequencies higher than 30MHz, we need
the setup the I/O line delays in regard of the SPI clock frequency.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20200312133131.26430-7-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The G12A SPICC controller variant takes the source clock from a specific
clock instead of the bus clock.
The minimal clock calculus won't work with the G12A support, thus add the
minimal supported clock for each variant and pass this to the SPI core.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20200312133131.26430-6-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The SPICC controller in Meson-AXG is capable of running at 80M clock.
The ASIC IP is improved and the clock is actually running higher than
previous old SoCs.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Sunny Luo <sunny.luo@amlogic.com>
Link: https://lore.kernel.org/r/20200312133131.26430-5-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The SPICC controller in Meson-AXG SoC is capable of using
a linear clock divider to reach a much fine tuned range of clocks,
while the old controller only use a power of two clock divider,
result at a more coarse clock range.
Also convert the clock registration into Common Clock Framework.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Sunny Luo <sunny.luo@amlogic.com>
Link: https://lore.kernel.org/r/20200312133131.26430-4-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The SPICC controller in Meson-AXG is capable of driving the CLK/MOSI/SS
signal lines through the idle state (between two transmission operation),
which avoid the signals floating in unexpected state.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Sunny Luo <sunny.luo@amlogic.com>
Link: https://lore.kernel.org/r/20200312133131.26430-3-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The platform_get_resource_byname() function returns NULL on error, it
doesn't return error pointers.
Fixes: d166a73503 ("spi: fspi: dynamically alloc AHB memory")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200312113154.GC20562@mwanda
Signed-off-by: Mark Brown <broonie@kernel.org>
This patchset from Chuanhong Guo <gch981213@gmail.com> adds a spi-mem
driver for Mediatek SPI-NOR controller, which already has limited
support by mtk-quadspi. This new driver can make use of full quadspi
capability of this controller.
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Merge tag 'mtk-mtd-spi-move' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-5.7
spi: Rewrite mtk-quadspi spi-nor driver with spi-mem
This patchset from Chuanhong Guo <gch981213@gmail.com> adds a spi-mem
driver for Mediatek SPI-NOR controller, which already has limited
support by mtk-quadspi. This new driver can make use of full quadspi
capability of this controller.
This is a driver for mtk spi-nor controller using spi-mem interface.
The same controller already has limited support provided by mtk-quadspi
driver under spi-nor framework and this new driver is a replacement
for the old one.
Comparing to the old driver, this driver has following advantages:
1. It can handle any full-duplex spi transfer up to 6 bytes, and
this is implemented using generic spi interface.
2. It take account into command opcode properly. The reading routine
in this controller can only use 0x03 or 0x0b as opcode on 1-1-1
transfers, but old driver doesn't implement this properly. This
driver checks supported opcode explicitly and use (1) to perform
unmatched operations.
3. It properly handles SFDP reading. Old driver can't read SFDP
due to the bug mentioned in (2).
4. It can do 1-2-2 and 1-4-4 fast reading on spi-nor. These two ops
requires parsing SFDP, which isn't possible in old driver. And
the old driver is only flagged to support 1-1-2 mode.
5. It takes advantage of the DMA feature in this controller for
long reads and supports IRQ on DMA requests to free cpu cycles
from polling status registers on long DMA reading. It achieves
up to 17.5MB/s reading speed (1-4-4 mode) which is way faster
than the old one. IRQ is implemented as optional to maintain
backward compatibility.
Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
Link: https://lore.kernel.org/r/20200306085052.28258-3-gch981213@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
We only need a spi-max-frequency when we specifically request a
spi frequency lower than the max speed of spi host.
This property is already documented as optional property and current
host drivers are implemented to operate at highest speed possible
when spi->max_speed_hz is 0.
This patch makes spi-max-frequency an optional property so that
we could just omit it to use max controller speed.
Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
Link: https://lore.kernel.org/r/20200306085052.28258-2-gch981213@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
By selecting MTD_SPI_NOR for SPI_HISI_SFC_V3XX, we may introduce unmet
dependencies:
WARNING: unmet direct dependencies detected for MTD_SPI_NOR
Depends on [m]: MTD [=m] && SPI_MASTER [=y]
Selected by [y]:
- SPI_HISI_SFC_V3XX [=y] && SPI [=y] && SPI_MASTER [=y] && (ARM64 && ACPI [=y] || COMPILE_TEST [=y]) && HAS_IOMEM [=y]
Since MTD_SPI_NOR is only selected by SPI_HISI_SFC_V3XX for practical
reasons - slave devices use the spi-nor driver, enabled by MTD_SPI_NOR -
just drop it.
Signed-off-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1583948115-239907-1-git-send-email-john.garry@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Use the correct device to request the DMA mapping. Otherwise the IOMMU
doesn't get the mapping and it will generate a page fault.
The error messages look like:
[ 3.008452] arm-smmu 5000000.iommu: Unhandled context fault: fsr=0x402, iova=0xf9800000, fsynr=0x3f0022, cbfrsynra=0x828, cb=8
[ 3.020123] arm-smmu 5000000.iommu: Unhandled context fault: fsr=0x402, iova=0xf9800000, fsynr=0x3f0022, cbfrsynra=0x828, cb=8
This was tested on a custom board with a LS1028A SoC.
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200310073313.21277-1-michael@walle.cc
Signed-off-by: Mark Brown <broonie@kernel.org>
All RSPI variants support setting the polarity of the SSL signal.
Advertize support for active-high chip selects, and configure polarity
according to the state of the flag.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200309171537.21551-1-geert+renesas@glider.be
Signed-off-by: Mark Brown <broonie@kernel.org>
The Rockchip spi binding is updated to yaml and new models
were added. The spi on px30,rk3308 and rk3328 are the same as
other Rockchip based SoCs, so add compatible string for it.
Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Link: https://lore.kernel.org/r/20200309151004.7780-1-jbx6244@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
There exists a set of SPI controllers on some POWER processors that may
be accessed through the FSI bus. Add a driver to traverse the FSI CFAM
engine that can access and drive the SPI controllers. This driver would
typically be used by a baseboard management controller (BMC).
The SPI controllers operate by means of programming a sequencing engine
which automatically manages the usual SPI protocol buses. The driver
programs each transfer into the sequencer as various operations
specifying the slave chip and shifting data in and out on the lines.
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20200306194118.18581-3-eajames@linux.ibm.com
Signed-off-by: Mark Brown <broonie@kernel.org>
commit a2ca53b52e ("spi: Add HiSilicon v3xx SPI NOR flash
controller driver") likely inadvertently used a select statement
with a CONFIG_ prefix, remove the prefix.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/f8ac6b32a29b9a05b58a7e58ffe8b780642abbf1.camel@perches.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Vladimir Oltean <vladimir.oltean@nxp.com>:
From: Vladimir Oltean <vladimir.oltean@nxp.com>
This series aims to remove the most inefficient transfer method from the
NXP DSPI driver.
TCFQ (Transfer Complete Flag) mode works by transferring one word,
waiting for its TX confirmation interrupt (or polling on the equivalent
status bit), sending the next word, etc, until the buffer is complete.
The issue with this mode is that it's fundamentally incompatible with
any sort of batching such as writing to a FIFO. But actually, due to
previous patchset ("Compatible string consolidation for NXP DSPI driver"):
https://patchwork.kernel.org/cover/11414593/
all existing users of TCFQ mode today already support a more advanced
feature set, in the form of XSPI (extended SPI). XSPI brings 2 extra
features:
- Word sizes up to 32 bits. This is sub-utilized today, and acceleration
of smaller-than-32 bpw values is provided.
- "Command cycling", basically the ability to write multiple words in a
row and receiving an interrupt only after the completion of the last
one. This is what enables us to make use of the full FIFO depth of
this controller.
Series was tested on the NXP LS1021A-TSN and LS1043A-RDB boards, both
functionally as well as from a performance standpoint.
The command used to benchmark the increased throughput was:
spidev_test --device /dev/spidev1.0 --bpw 8 --size 256 --cpha --iter 10000000 --speed 20000000
where spidev1.0 is a dummy spidev node, using a chip select that no
peripheral responds to.
On LS1021A, which has a 4-entry-deep FIFO and a less powerful CPU, the
performance increase brought by this patchset is from 2700 kbps to 5800
kbps.
On LS1043A, which has a 16-entry-deep FIFO and a more powerful CPU, the
performance increases from 4100 kbps to 13700 kbps.
On average, SPI software timestamping is not adversely affected by the
extra batching, due to the extra patches.
There is one extra patch which clarifies why the TCFQ users were not
converted to the "other" mode in this driver that makes use of the FIFO,
which would be EOQ mode.
My request to the many people on CC (known users and/or contributors) is
to give this series a test to ensure there are no regressions, and for
the Coldfire maintainers to clarify whether the EOQ limitation is
acceptable for them in the long run.
Vladimir Oltean (12):
spi: spi-fsl-dspi: Simplify bytes_per_word gymnastics
spi: spi-fsl-dspi: Remove unused chip->void_write_data
spi: spi-fsl-dspi: Don't mask off undefined bits
spi: spi-fsl-dspi: Add comments around dspi_pop_tx and dspi_push_rx
functions
spi: spi-fsl-dspi: Rename fifo_{read,write} and {tx,cmd}_fifo_write
spi: spi-fsl-dspi: Implement .max_message_size method for EOQ mode
spi: Do spi_take_timestamp_pre for as many times as necessary
spi: spi-fsl-dspi: Convert TCFQ users to XSPI FIFO mode
spi: spi-fsl-dspi: Accelerate transfers using larger word size if
possible
spi: spi-fsl-dspi: Optimize dspi_setup_accel for lowest interrupt
count
spi: spi-fsl-dspi: Use EOQ for last word in buffer even for XSPI mode
spi: spi-fsl-dspi: Take software timestamp in dspi_fifo_write
drivers/spi/spi-fsl-dspi.c | 421 ++++++++++++++++++++++++-------------
drivers/spi/spi.c | 19 +-
include/linux/spi/spi.h | 3 +-
3 files changed, 288 insertions(+), 155 deletions(-)
--
2.17.1
The SPI bus number is completely optional to Linux, so make the
corresponding device tree property optional as well.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Link: https://lore.kernel.org/r/20200305115546.31814-1-s.hauer@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Apply patch from NXP upstream repo to
Enable the octal combination mode in MCR0
Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Han Xu <han.xu@nxp.com>
Link: https://lore.kernel.org/r/20200126140913.2139260-3-aford173@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Apply patch from NXP upstream repo to
dynamically allocate AHB memory as needed.
Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Han Xu <han.xu@nxp.com>
Link: https://lore.kernel.org/r/20200126140913.2139260-2-aford173@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Pull in this patch from NXP's upstream repo to
enable fspi on imx8qxp and imx8mm
Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Han Xu <han.xu@nxp.com>
Link: https://lore.kernel.org/r/20200126140913.2139260-1-aford173@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Although the SPI system timestamps are supposed to reflect the moment
that the peripheral has received a word rather than the moment when the
CPU has enqueued that word to the FIFO, in practice it is easier to just
record the latter time than the former (with a smaller error).
With the recent migration of TCFQ users from poll back to interrupt mode
(this time for XSPI FIFO), it's wiser to keep the interrupt latency
outside of the measurement of the PTP system timestamp itself. If there
proves to be any constant offset that requires static compensation, that
can always be added later. So far that does not appear to be the case at
least on the LS1021A-TSN board, where testing shows that the phc2sys
offset is able to remain within +/- 200 ns even after 68 hours of
testing.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-13-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The EOQ mode has a hardware limitation in that it stops the transmission
(including the deassertion of the chip select signal) once the host CPU
requests end-of-queue for a particular word in the TX FIFO.
And XSPI mode has a limitation in that we need a separate CMD FIFO entry
for the last byte in the buffer, where the chip select signal needs to
be deasserted. It's not a functional limitation, but it's rather clunky
and the fact that we need to halt the pipeline and write a single entry
to the TX FIFO whenever a buffer ends brings the throughput down when
transmitting small buffers.
So the idea here is to use EOQ's limitation in our favor when using XSPI
mode. Stop special-casing that final word in the buffer, and just kill
the chip select signal by issuing an EOQ for that last word. Now it can
be mixed in with all the other words in the current TX FIFO train.
A small trick here is that we still keep using the XSPI-specific
signaling via the CMDTCFQ interrupt in RSER, and not enabling the EOQ
interrupt, in order to avoid hardware weirdness (potential races with
separate interrupts being raised for CMDTCFQ and EOQ for what is in fact
the end of the same transmission). That is just theoretical, but it's
good to be cautious, and the EOQ interrupt isn't needed.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-12-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently, a SPI transfer that is not multiple of the highest supported
word width (e.g. 4 bytes) will be transmitted as follows (assume a
30-byte buffer transmitted through a 32-bit wide FIFO that is 32 bytes
deep):
- First 28 bytes are sent as 7 words of 32 bits each
- Last 2 bytes are sent as 1 word of 16 bits size
But if the dspi_setup_accel function had decided to use a lower
oper_bits_per_word value (16 instead of 32), there would have been
enough space in the TX FIFO to fit the entire buffer in one go (15 words
of 16 bits each).
What we're actually trying to avoid is mixing word sizes within the same
run with the TX FIFO, since there is an erratum surrounding this, and
invalid data might get transmitted.
So this patch adds special cases for when the remaining length of the
buffer can be sent in one go as 8-bit or 16-bit words, otherwise it
falls back to the standard logic of sending as many bytes as possible at
the highest oper_bits_per_word value possible.
The benefit is that there will be one less CMDFQ/EOQ interrupt to
service when the entire buffer is transmitted during a single go, and
that will improve the overall latency of the transfer.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-11-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch adds logic in the driver to transmit SPI buffers that use
bits_per_word=8 with a higher bits_per_word count (multiple of 8).
Currently the following (most common) modes are implemented:
- 8 bits_per_word on 32-bit capable controllers
- 8 bits_per_word on 16-bit capable controllers
- 16 bits_per_word on 32-bit capable controllers
Transfers which are not accelerated are transferred with a hardware
bits_per_word value equal to the one of the SPI transfer.
The difference from just extending bits_per_word=32 at the spi_device
driver level is that endianness is different - the SPI core wants to
treat bits_per_word=32 buffers as arrays of u32 (i.e. words in host CPU
endianness). So to preserve endianness when clumping 8x4 bits into
32-bit words, one must perform conversion between CPU and standard (big)
endianness.
All appearances (both on the wire as well as in the buffers presented to
the peripheral driver) are preserved, just that accesses to the PUSHR
and POPR registers are now more efficient, since the same number of
reads/writes can now carry more data (2x more data on TX, 4x more data
on RX).
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-10-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The Transfer Complete Flag (TCF) interrupt gets raised after each write
to the TX FIFO (PUSHR) which means that it is not possible to devise a
transfer procedure that makes full utilization of the FIFO depth (4
entries on most controllers, 16 entries on some).
On the other hand, XSPI mode has a feature called "command cycling",
which allows a single TX command to be run for a pre-specified number of
TX words. When the command cycle ends, the Command Transfer Complete
Flag bit asserts and raises an interrupt. The advantage in this mode is
that the TX FIFO can be better utilized (more words can be batched at
once).
Other changes brought by this patch:
- The dspi->rx_end variable has been removed, since now the
dspi_fifo_write function sets up dspi->words_in_flight, so
dspi_fifo_read knows how much to read without overrunning the RX
buffer.
- Stop using poll mode unconditionally for TCFQ mode, since XSPI mode
is a little less efficient than that, and so, poll mode doesn't bring
as many improvements for XSPI.
- Stop relying on the hardware transfer counter (SPI_TCR_GET_TCNT) and
instead increment the message->actual_length based on the newly
introduced dspi->words_in_flight variable.
- The CTARE register is now written in the hotpath instead of just at
transfer init time, since it contains the DTCP field (transfer
preload - the counter indicating how many txdata words will follow),
which is a dynamic value.
Due to the fact that the Chip Select toggling setting is part of the
command written to the TX FIFO, the ending word of each buffer needs to
be sent via its own TX command, so that we have a chance to emit a
1-word command with deasserted PCS.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-9-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
When dealing with a SPI controller driver that is sending more than 1
byte at once (or the entire buffer at once), and the SPI peripheral
driver has requested timestamping for a byte in the middle of the
buffer, we find that spi_take_timestamp_pre never records a "pre"
timestamp.
This happens because the function currently expects to be called with
the "progress" argument >= to what the peripheral has requested to be
timestamped. But clearly there are cases when that isn't going to fly.
And since we can't change the past when we realize that the opportunity
to take a "pre" timestamp has just passed and there isn't going to be
another one, the approach taken is to keep recording the "pre" timestamp
on each call, overwriting the previously recorded one until the "post"
timestamp is also taken.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-8-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
When it gets set, End Of Queue Flag halts the DSPI controller and forces
the chip select signal to deassert.
This operating mode is not ideal, but it is used for the DSPI
instantiations where there is no other notification from the controller
that the data in the FIFO has finished transmission. So in practice, it
means that transmitting buffers larger than the FIFO size will yield
unpredictable results.
The only controller that operates in EOQ mode is MCF5441X (Coldfire). I
would say that the way EOQ is used (and documented in the reference
manual, too) on this chip is incorrect, and I would personally migrate
it to TCFQ, but that's notably worse in terms of performance (it can
only use 1 entry of the 16-deep FIFO) and if this limitation didn't
bother any Coldfire DSPI user so far, it's likely that we just need to
throw an error for larger buffers to make sure that callers are aware
their transfers are getting truncated/split.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-7-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
These function names are very generic and it is easy to get confused.
Rename them after the hardware register that they are accessing.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-6-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Their names are confusing, since dspi_pop_tx prepares a word to be
written to the PUSHR register, and dspi_push_rx gets a word from the
POPR register.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-5-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This is a useless operation, and if the driver needs to do that, there's
something deeply wrong going on.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-4-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This variable has been present since the initial submission of the
driver, and held, for some reason, the value of zero, to be sent on the
wire in the case there wasn't any TX buffer for the current transfer.
Since quite a while now, however, it isn't doing anything at all.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-3-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Reduce the if-then-else-if-then-else sequence to:
- a simple division in the case of bytes_per_word calculation
- a memcpy command with a variable size. The semantics of larger-than-8
xfer->bits_per_word is that those words are to be interpreted and
transmitted in CPU native endianness.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-2-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This series makes room in the driver for differentiation between the
controllers which currently operate in TCFQ mode. Most of these are
actually capable of a lot more in terms of throughput. This is in
preparation of a second series which will convert the remaining users of
TCFQ mode altogether to XSPI mode with command cycling.
Vladimir Oltean (6):
doc: spi-fsl-dspi: Add specific compatibles for all Layerscape SoCs
spi: spi-fsl-dspi: Use specific compatible strings for all SoC
instantiations
spi: spi-fsl-dspi: Parameterize the FIFO size and DMA buffer size
spi: spi-fsl-dspi: LS2080A and LX2160A support XSPI mode
spi: spi-fsl-dspi: Support SPI software timestamping in all non-DMA
modes
spi: spi-fsl-dspi: Convert the instantiations that support it to DMA
.../devicetree/bindings/spi/spi-fsl-dspi.txt | 17 +-
drivers/spi/spi-fsl-dspi.c | 162 +++++++++++++-----
2 files changed, 128 insertions(+), 51 deletions(-)
--
2.17.1
The A-011218 eDMA/DSPI erratum affects most of the older Layerscape SoCs
with DSPI, and its workaround is a bit intrusive.
After this patch, there are no users of TCFQ mode that don't also
support XSPI (previously there was LS2085A).
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Message-Id: <20200302001958.11105-7-olteanv@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There's no reason to keep this .ptp_sts_supported property explicitly in
devtype_data, since it can be deduced from the operating mode alone.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Message-Id: <20200302001958.11105-6-olteanv@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
XSPI allows for 2 extra features:
- Command cycling (use a single TX command with more than 1 word in the
TX FIFO).
- Increased word size (from 16 bits to 32 bits)
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Message-Id: <20200302001958.11105-5-olteanv@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Get rid of the ifdef for Coldfire and make these hardware
characteristics part of dspi->devtype_data.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Message-Id: <20200302001958.11105-4-olteanv@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently, the device tree bindings submitted in mainline for Layerscape
SoCs look like this:
LS1021A:
compatible = "fsl,ls1021a-v1.0-dspi";
LS1012A:
compatible = "fsl,ls1012a-dspi", "fsl,ls1021a-v1.0-dspi";
LS2085A:
compatible = "fsl,ls2085a-dspi";
LS2088A:
compatible = "fsl,ls2080a-dspi", "fsl,ls2085a-dspi";
LX2160A:
compatible = "fsl,lx2160a-dspi", "fsl,ls2085a-dspi";
LS1043A:
compatible = "fsl,ls1043a-dspi", "fsl,ls1021a-v1.0-dspi";
LS1046A:
compatible = "fsl,ls1021a-v1.0-dspi";
Due to a lack of a more specific compatible string, LS1012A, LS1043A and
LS1046A will fall under the LS1021A umbrella, and LS2088A and LX2160A
under the LS2085A umbrella.
They do work in those modes, but there are slight differences in the
hardware instantiations, mostly related to FIFO sizes (with the more
specific compatible strings, the FIFO size can be increased properly).
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Message-Id: <20200302001958.11105-3-olteanv@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The message of max device speed setting is shown when
an error in spi_setup() occurs.
Instead, it should be shown when the setup call succeeds.
Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
Link: https://lore.kernel.org/r/20200229161841.89144-3-oleksandr.suvorov@toradex.com
Signed-off-by: Mark Brown <broonie@kernel.org>
