Generic DMA support is going to be part of the DW APB SSI core object.
In order to preserve the kernel loadable module name as spi-dw.ko, let's
add the "-core" suffix to the object with generic DW APB SSI code and
build it into the target spi-dw.ko driver.
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200529131205.31838-10-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Tx-only DMA transfers are working perfectly fine since in this case
the code just ignores the Rx FIFO overflow interrupts. But it turns
out the SPI Rx-only transfers are broken since nothing pushing any
data to the shift registers, so the Rx FIFO is left empty and the
SPI core subsystems just returns a timeout error. Since DW DMAC
driver doesn't support something like cyclic write operations of
a single byte to a device register, the only way to support the
Rx-only SPI transfers is to fake it by using a dummy Tx-buffer.
This is what we intend to fix in this commit by setting the
SPI_CONTROLLER_MUST_TX flag for DMA-capable platform.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200529131205.31838-9-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Each channel of DMA controller may have a limited length of burst
transaction (number of IO operations performed at ones in a single
DMA client request). This parameter can be used to setup the most
optimal DMA Tx/Rx data level values. In order to avoid the Tx buffer
overrun we can set the DMA Tx level to be of FIFO depth minus the
maximum burst transactions length. To prevent the Rx buffer underflow
the DMA Rx level should be set to the maximum burst transactions length.
This commit setups the DMA channels and the DW SPI DMA Tx/Rx levels
in accordance with these rules.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200529131205.31838-8-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
It isn't good to have numeric literals in the code especially if there
are multiple of them and they are related. Let's replace the Tx and Rx
burst level literals with the corresponding constants.
Co-developed-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Co-developed-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200529131205.31838-7-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Having any data left in the Rx FIFO after the DMA engine claimed it has
finished all DMA transactions is an abnormal situation, since the DW SPI
controller driver expects to have all the data being fetched and placed
into the SPI Rx buffer at that moment. In case if that has happened we
hopefully assume that the DMA engine may still be doing the data fetching,
thus we give it sometime to finish. If after a short period of time the
data is still left in the Rx FIFO, the driver will give up waiting and
return an error indicating that the SPI controller/DMA engine must have
hung up or failed at some point of doing their duties.
Fixes: 7063c0d942 ("spi/dw_spi: add DMA support")
Co-developed-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200529131205.31838-6-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Since DMA transfers are performed asynchronously with actual SPI bus
transfers, then even if DMA transactions are finished it doesn't mean
all data is actually pushed to the SPI bus. Some data might still be
in the controller FIFO. This is specifically true for Tx-only transfers.
In this case if the next SPI transfer is recharged while a tail of the
previous one is still in FIFO, we'll loose that tail data. In order to
fix that problem let's add the wait procedure of the Tx SPI transfer
completion after the DMA transactions are finished.
Fixes: 7063c0d942 ("spi/dw_spi: add DMA support")
Co-developed-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200529131205.31838-5-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
In general each DMA-based SPI transfer can be split up into two stages:
DMA data transmission/reception and SPI-bus transmission/reception. DMA
asynchronous transactions completion can be tracked by means of the
DMA async Tx-descriptor completion callback. But that callback being
called indicates that the DMA transfer has been finished, it doesn't
mean that SPI data transmission is also done. Moreover in fact it isn't
for at least Tx-only SPI transfers. Upon DMA transfer completion some
data is left in the Tx FIFO and being pushed out by the SPI controller.
So in order to make sure that an SPI transfer is completely pushed to the
SPI-bus, the driver has to wait for both DMA transaction and the SPI-bus
transmission/reception are finished. Note if there is a way to
asynchronously track the former event by means of the DMA async Tx
callback, there isn't easy one for the later (IRQ-based solution won't
work since SPI controller doesn't notify about Rx FIFO being empty).
The DMA transfer completion callback isn't suitable to wait for the
SPI controller activity finish either. The callback might (in case of DW
DMAC it will) be called in the tasklet context. Waiting for the SPI
controller to complete the transfer might take a considerable amount of
time since SPI-bus might be pretty slow. In this case delaying the
execution in the tasklet atomic context might cause significant system
performance drop.
So to speak the best option we've got to solve the problem is to
consequently wait for both stages being finished in the locally
implemented SPI transfer execution procedure even if it costs us of the
local wait-function re-implementation. In this case we don't need to use
the SPI-core transfer-wait functionality, but we'll make sure that
all DMA and SPI-bus transactions are completely finished before the
SPI-core transfer_one callback returns. In this commit we provide an
implementation of the DMA-transfers completion wait functionality.
The DW APB SSI DMA-specific SPI transfer_one function waits for both
Tx and Rx DMA transfers being finished, and only then exits with zero
returned signalling to the SPI core that the SPI transfer is finished.
This implementation is fully equivalent to the currently used
DMA-execution-SPI-core-wait algorithm. The SPI-bus transmission/reception
wait methods will be added in the follow-up commits.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200529131205.31838-4-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
DW APB SSI DMA-part of the driver may need to perform the requested
SPI-transfer synchronously. In that case the dma_transfer() callback
will return 0 as a marker of the SPI transfer being finished so the
SPI core doesn't need to wait and may proceed with the SPI message
trasnfers pumping procedure. This will be needed to fix the problem
when DMA transactions are finished, but there is still data left in
the SPI Tx/Rx FIFOs being sent/received. But for now make dma_transfer
to return 1 as the normal dw_spi_transfer_one() method.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200529131205.31838-3-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Seeing DW APB SSI controller doesn't support setting the exactly
requested SPI bus frequency, but only a rounded frequency determined
by means of the odd-numbered half-worded reference clock divider,
it would be good to tune the SPI core up and initialize the current
transfer effective_speed_hz. By doing so the core will be able to
execute the xfer-related delays with better accuracy.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200529131205.31838-2-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
There is ecspi ERR009165 on i.mx6/7 soc family, which cause FIFO
transfer to be send twice in DMA mode. Please get more information from:
https://www.nxp.com/docs/en/errata/IMX6DQCE.pdf. The workaround is adding
new sdma ram script which works in XCH mode as PIO inside sdma instead
of SMC mode, meanwhile, 'TX_THRESHOLD' should be 0. The issue should be
exist on all legacy i.mx6/7 soc family before i.mx6ul.
NXP fix this design issue from i.mx6ul, so newer chips including i.mx6ul/
6ull/6sll do not need this workaroud anymore. All other i.mx6/7/8 chips
still need this workaroud. This patch set add new 'fsl,imx6ul-ecspi'
for ecspi driver and 'ecspi_fixed' in sdma driver to choose if need errata
or not.
The first two reverted patches should be the same issue, though, it
seems 'fixed' by changing to other shp script. Hope Sean or Sascha could
have the chance to test this patch set if could fix their issues.
Besides, enable sdma support for i.mx8mm/8mq and fix ecspi1 not work
on i.mx8mm because the event id is zero.
PS:
Please get sdma firmware from below linux-firmware and copy it to your
local rootfs /lib/firmware/imx/sdma.
https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/tree/imx/sdma
v2:
1.Add commit log for reverted patches.
2.Add comment for 'ecspi_fixed' in sdma driver.
3.Add 'fsl,imx6sll-ecspi' compatible instead of 'fsl,imx6ul-ecspi'
rather than remove.
v3:
1.Confirm with design team make sure ERR009165 fixed on i.mx6ul/i.mx6ull
/i.mx6sll, not fixed on i.mx8m/8mm and other i.mx6/7 legacy chips.
Correct dts related dts patch in v2.
2.Clean eratta information in binding doc and new 'tx_glitch_fixed' flag
in spi-imx driver to state ERR009165 fixed or not.
3.Enlarge burst size to fifo size for tx since tx_wml set to 0 in the
errata workaroud, thus improve performance as possible.
v4:
1.Add Ack tag from Mark and Vinod
2.Remove checking 'event_id1' zero as 'event_id0'.
v5:
1.Add the last patch for compatible with the current uart driver which
using rom script, so both uart ram script and rom script supported
in latest firmware, by default uart rom script used. UART driver
will be broken without this patch.
v6:
1.Resend after rebase the latest next branch.
2.Remove below No.13~No.15 patches of v5 because they were mergered.
ARM: dts: imx6ul: add dma support on ecspi
ARM: dts: imx6sll: correct sdma compatible
arm64: defconfig: Enable SDMA on i.mx8mq/8mm
3.Revert "dmaengine: imx-sdma: fix context cache" since
'context_loaded' removed.
v7:
1.Put the last patch 13/13 'Revert "dmaengine: imx-sdma: fix context
cache"' to the ahead of 03/13 'Revert "dmaengine: imx-sdma: refine
to load context only once" so that no building waring during comes out
during bisect.
2.Address Sascha's comments, including eliminating any i.mx6sx in this
series, adding new 'is_imx6ul_ecspi()' instead imx in imx51 and taking
care SMC bit for PIO.
3.Add back missing 'Reviewed-by' tag on 08/15(v5):09/13(v7)
'spi: imx: add new i.mx6ul compatible name in binding doc'
v8:
1.remove 0003-Revert-dmaengine-imx-sdma-fix-context-cache.patch and merge
it into 04/13 of v7
2.add 0005-spi-imx-fallback-to-PIO-if-dma-setup-failure.patch for no any
ecspi function broken even if sdma firmware not updated.
3.merge 'tx.dst_maxburst' changes in the two continous patches into one
patch to avoid confusion.
4.fix typo 'duplicated'.
Robin Gong (13):
Revert "ARM: dts: imx6q: Use correct SDMA script for SPI5 core"
Revert "ARM: dts: imx6: Use correct SDMA script for SPI cores"
Revert "dmaengine: imx-sdma: refine to load context only once"
dmaengine: imx-sdma: remove duplicated sdma_load_context
spi: imx: fallback to PIO if dma setup failure
dmaengine: imx-sdma: add mcu_2_ecspi script
spi: imx: fix ERR009165
spi: imx: remove ERR009165 workaround on i.mx6ul
spi: imx: add new i.mx6ul compatible name in binding doc
dmaengine: imx-sdma: remove ERR009165 on i.mx6ul
dma: imx-sdma: add i.mx6ul compatible name
dmaengine: imx-sdma: fix ecspi1 rx dma not work on i.mx8mm
dmaengine: imx-sdma: add uart rom script
.../devicetree/bindings/dma/fsl-imx-sdma.txt | 1 +
.../devicetree/bindings/spi/fsl-imx-cspi.txt | 1 +
arch/arm/boot/dts/imx6q.dtsi | 2 +-
arch/arm/boot/dts/imx6qdl.dtsi | 8 +-
drivers/dma/imx-sdma.c | 67 ++++++++++------
drivers/spi/spi-imx.c | 92 +++++++++++++++++++---
include/linux/platform_data/dma-imx-sdma.h | 8 +-
7 files changed, 135 insertions(+), 44 deletions(-)
--
2.7.4
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.orghttp://lists.infradead.org/mailman/listinfo/linux-arm-kernel
pm_runtime_get_sync() increments the runtime PM usage counter even
when it returns an error code. Thus a pairing decrement is needed on
the error handling path to keep the counter balanced.
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Link: https://lore.kernel.org/r/20200523124758.28604-1-dinghao.liu@zju.edu.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync() increments the runtime PM usage counter even
when it returns an error code. Thus a pairing decrement is needed on
the error handling path to keep the counter balanced.
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Link: https://lore.kernel.org/r/20200523122909.25247-1-dinghao.liu@zju.edu.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync() increments the runtime PM usage counter even
when it returns an error code. Thus a pairing decrement is needed on
the error handling path to keep the counter balanced.
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Link: https://lore.kernel.org/r/20200523125704.30300-1-dinghao.liu@zju.edu.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
Fallback to PIO in case dma setup failed. For example, sdma firmware not
updated but ERR009165 workaroud added in kernel.
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Link: https://lore.kernel.org/r/1590006865-20900-6-git-send-email-yibin.gong@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync() increments the runtime PM usage counter even
when it returns an error code. Thus a pairing decrement is needed on
the error handling path to keep the counter balanced.
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Link: https://lore.kernel.org/r/20200523133859.5625-1-dinghao.liu@zju.edu.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
Originally spi_write_then_read() used a fixed statically allocated
buffer which limited the maximum message size it could handle. This
restriction was removed a while ago so that we could dynamically
allocate a buffer if required but the kerneldoc was not updated to
reflect this, do so.
Reported-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20200525133120.57273-1-broonie@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
since chip spi driver need get the transfer direction by 'tx_buf' and
'rx_buf' of 'struct spi_transfer' in 'SPI_3WIRE' mode.
so, we need bypass 'SPI_CONTROLLER_MUST_RX' and 'SPI_CONTROLLER_MUST_TX'
feature in 'SPI_3WIRE' mode
Signed-off-by: dillon min <dillon.minfei@gmail.com>
Link: https://lore.kernel.org/r/1590378348-8115-9-git-send-email-dillon.minfei@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
in l3gd20 driver startup, there is a setup failed error return from
stm32 spi driver
"
[ 2.687630] st-gyro-spi spi0.0: supply vdd not found, using dummy
regulator
[ 2.696869] st-gyro-spi spi0.0: supply vddio not found, using dummy
regulator
[ 2.706707] spi_stm32 40015000.spi: SPI transfer setup failed
[ 2.713741] st-gyro-spi spi0.0: SPI transfer failed: -22
[ 2.721096] spi_master spi0: failed to transfer one message from queue
[ 2.729268] iio iio:device0: failed to read Who-Am-I register.
[ 2.737504] st-gyro-spi: probe of spi0.0 failed with error -22
"
after debug into spi-stm32 driver, st-gyro-spi split two steps to read
l3gd20 id
first: send command to l3gd20 with read id command in tx_buf, rx_buf
is null.
second: read id with tx_buf is null, rx_buf not null.
so, for second step, stm32 driver recongise this process as 'SPI_SIMPLE_RX'
from stm32_spi_communication_type(), but there is no related process for this
type in stm32f4_spi_set_mode(), then we get error from
stm32_spi_transfer_one_setup().
we can use two method to fix this bug.
1, use stm32 spi's "In unidirectional receive-only mode (BIDIMODE=0 and
RXONLY=1)". but as our code running in sdram, the read latency is too large
to get so many receive overrun error in interrupts handler.
2, use stm32 spi's "In full-duplex (BIDIMODE=0 and RXONLY=0)", as tx_buf is
null, so add flag 'SPI_MASTER_MUST_TX' to spi master.
Change since V4:
1 remove dummy data sent out by stm32 spi driver
2 add flag 'SPI_MASTER_MUST_TX' to spi master
Signed-off-by: dillon min <dillon.minfei@gmail.com>
Link: https://lore.kernel.org/r/1590378348-8115-8-git-send-email-dillon.minfei@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
If the delay used is long enough the spi_delay_exec() will use a sleeping
function to implement it. Add a might_sleep() here to help avoid callers
using this from an atomic context and running into problems at runtime on
other systems.
Suggested-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200522155005.46099-1-broonie@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Baikal-T1 SoC provides a DW DMA controller to perform low-speed peripherals
Mem-to-Dev and Dev-to-Mem transaction. This is also applicable to the DW
APB SSI devices embedded into the SoC. Currently the DMA-based transfers
are supported by the DW APB SPI driver only as a middle layer code for
Intel MID/Elkhart PCI devices. Seeing the same code can be used for normal
platform DMAC device we introduced a set of patches to fix it within this
series.
First of all we need to add the Tx and Rx DMA channels support into the DW
APB SSI binding. Then there are several fixes and cleanups provided as a
initial preparation for the Generic DMA support integration: add Tx/Rx
finish wait methods, clear DMAC register when done or stopped, Fix native
CS being unset, enable interrupts in accordance with DMA xfer mode,
discard static DW DMA slave structures, discard unused void priv pointer
and dma_width member of the dw_spi structure, provide the DMA Tx/Rx burst
length parametrisation and make sure it's optionally set in accordance
with the DMA max-burst capability.
In order to have the DW APB SSI MMIO driver working with DMA we need to
initialize the paddr field with the physical base address of the DW APB SSI
registers space. Then we unpin the Intel MID specific code from the
generic DMA one and placed it into the spi-dw-pci.c driver, which is a
better place for it anyway. After that the naming cleanups are performed
since the code is going to be used for a generic DMAC device. Finally the
Generic DMA initialization can be added to the generic version of the
DW APB SSI IP.
Last but not least we traditionally convert the legacy plain text-based
dt-binding file with yaml-based one and as a cherry on a cake replace
the manually written DebugFS registers read method with a ready-to-use
for the same purpose regset32 DebugFS interface usage.
This patchset is rebased and tested on the spi/for-next (5.7-rc5):
base-commit: fe9fce6b2cf3 ("Merge remote-tracking branch 'spi/for-5.8' into spi-next")
Link: https://lore.kernel.org/linux-spi/20200508132943.9826-1-Sergey.Semin@baikalelectronics.ru/
Changelog v2:
- Rebase on top of the spi repository for-next branch.
- Move bindings conversion patch to the tail of the series.
- Move fixes to the head of the series.
- Apply as many changes as possible to be applied the Generic DMA
functionality support is added and the spi-dw-mid is moved to the
spi-dw-dma driver.
- Discard patch "spi: dw: Fix dma_slave_config used partly uninitialized"
since the problem has already been fixed.
- Add new patch "spi: dw: Discard unused void priv pointer".
- Add new patch "spi: dw: Discard dma_width member of the dw_spi structure".
n_bytes member of the DW SPI data can be used instead.
- Build the DMA functionality into the DW APB SSI core if required instead
of creating a separate kernel module.
- Use conditional statement instead of the ternary operator in the ref
clock getter.
Link: https://lore.kernel.org/linux-spi/20200515104758.6934-1-Sergey.Semin@baikalelectronics.ru/
Changelog v3:
- Use spi_delay_exec() method to wait for the DMA operation completion.
- Explicitly initialize the dw_dma_slave members on stack.
- Discard the dws->fifo_len utilization in the Tx FIFO DMA threshold
setting from the patch where we just add the default burst length
constants.
- Use min() method to calculate the optimal burst values.
- Add new patch which moves the spi-dw.c source file to spi-dw-core.c in
order to preserve the DW APB SSI core driver name.
- Add commas in the debugfs_reg32 structure initializer and after the last
entry of the dw_spi_dbgfs_regs array.
Link: https://lore.kernel.org/linux-spi/20200521012206.14472-1-Sergey.Semin@baikalelectronics.ru
Changelog v4:
- Get back ndelay() method to wait for an SPI transfer completion.
spi_delay_exec() isn't suitable for the atomic context.
Co-developed-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Co-developed-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Maxim Kaurkin <Maxim.Kaurkin@baikalelectronics.ru>
Cc: Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>
Cc: Ekaterina Skachko <Ekaterina.Skachko@baikalelectronics.ru>
Cc: Vadim Vlasov <V.Vlasov@baikalelectronics.ru>
Cc: Alexey Kolotnikov <Alexey.Kolotnikov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-spi@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Serge Semin (16):
spi: dw: Add Tx/Rx finish wait methods to the MID DMA
spi: dw: Enable interrupts in accordance with DMA xfer mode
spi: dw: Discard static DW DMA slave structures
spi: dw: Discard unused void priv pointer
spi: dw: Discard dma_width member of the dw_spi structure
spi: dw: Parameterize the DMA Rx/Tx burst length
spi: dw: Use DMA max burst to set the request thresholds
spi: dw: Fix Rx-only DMA transfers
spi: dw: Add core suffix to the DW APB SSI core source file
spi: dw: Move Non-DMA code to the DW PCIe-SPI driver
spi: dw: Remove DW DMA code dependency from DW_DMAC_PCI
spi: dw: Add DW SPI DMA/PCI/MMIO dependency on the DW SPI core
spi: dw: Cleanup generic DW DMA code namings
spi: dw: Add DMA support to the DW SPI MMIO driver
spi: dw: Use regset32 DebugFS method to create regdump file
dt-bindings: spi: Convert DW SPI binding to DT schema
.../bindings/spi/snps,dw-apb-ssi.txt | 44 ---
.../bindings/spi/snps,dw-apb-ssi.yaml | 127 +++++++++
.../devicetree/bindings/spi/spi-dw.txt | 24 --
drivers/spi/Kconfig | 15 +-
drivers/spi/Makefile | 5 +-
drivers/spi/{spi-dw.c => spi-dw-core.c} | 88 ++----
drivers/spi/{spi-dw-mid.c => spi-dw-dma.c} | 261 ++++++++++--------
drivers/spi/spi-dw-mmio.c | 4 +
drivers/spi/spi-dw-pci.c | 50 +++-
drivers/spi/spi-dw.h | 33 ++-
10 files changed, 392 insertions(+), 259 deletions(-)
delete mode 100644 Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.txt
create mode 100644 Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
delete mode 100644 Documentation/devicetree/bindings/spi/spi-dw.txt
rename drivers/spi/{spi-dw.c => spi-dw-core.c} (82%)
rename drivers/spi/{spi-dw-mid.c => spi-dw-dma.c} (55%)
--
2.25.1
This patch fixes a null pointer bug in the spi driver spi-rb4xx.c by
moving the private data initialization to earlier in probe
Signed-off-by: Christopher Hill <ch6574@gmail.com>
Link: https://lore.kernel.org/r/20200521183631.37806-1-ch6574@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This member has exactly the same value as n_bytes of the DW SPI private
data object, it's calculated at the same point of the transfer method,
n_bytes isn't changed during the whole transfer, and they even serve for
the same purpose - keep number of bytes per transfer word, though the
dma_width is used only to calculate the DMA source/destination addresses
width, which n_bytes could be also utilized for. Taking all of these
into account let's replace the dma_width member usage with n_bytes one
and remove the former.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200522000806.7381-6-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Seeing the "void *priv" member of the dw_spi data structure is unused
let's remove it. The glue-layers can embed the DW APB SSI controller
descriptor into their private data object. MMIO driver for instance
already utilizes that design pattern.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200522000806.7381-5-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Having them declared is redundant since each struct dw_dma_chan has
the same structure embedded and the structure from the passed dma_chan
private pointer will be copied there as a result of the next calls
chain:
dma_request_channel() -> find_candidate() -> dma_chan_get() ->
device_alloc_chan_resources() = dwc_alloc_chan_resources() ->
dw_dma_filter().
So just remove the static dw_dma_chan structures and use a locally
declared data instance with dst_id/src_id set to the same values as
the static copies used to have.
Co-developed-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Co-developed-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200522000806.7381-4-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
It's pointless to track the Tx overrun interrupts if Rx-only SPI
transfer is issued. Similarly there is no need in handling the Rx
overrun/underrun interrupts if Tx-only SPI transfer is executed.
So lets unmask the interrupts only if corresponding SPI
transactions are implied.
Co-developed-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200522000806.7381-3-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
On unbind of the BCM2835 SPI driver, the SPI controller is disabled
first and the DMA channels are terminated and torn down afterwards.
This seems backwards: In the theoretical case that DMA is active,
it might try to fill the SPI FIFOs even after the controller has
been disabled.
Reverse the order, thereby mirroring what's done on ->probe().
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/ac79f1e3d6fd9a1f5e0cb4008c43b98ea70be3c2.1589557526.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
The BCM2835aux SPI driver uses devm_spi_register_master() on bind.
As a consequence, on unbind, __device_release_driver() first invokes
bcm2835aux_spi_remove() before unregistering the SPI controller via
devres_release_all().
This order is incorrect: bcm2835aux_spi_remove() turns off the SPI
controller, including its interrupts and clock. The SPI controller
is thus no longer usable.
When the SPI controller is subsequently unregistered, it unbinds all
its slave devices. If their drivers need to access the SPI bus,
e.g. to quiesce their interrupts, unbinding will fail.
As a rule, devm_spi_register_master() must not be used if the
->remove() hook performs teardown steps which shall be performed
after unbinding of slaves.
Fix by using the non-devm variant spi_register_master(). Note that the
struct spi_master as well as the driver-private data are not freed until
after bcm2835aux_spi_remove() has finished, so accessing them is safe.
Fixes: 1ea29b39f4 ("spi: bcm2835aux: add bcm2835 auxiliary spi device driver")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v4.4+
Cc: Martin Sperl <kernel@martin.sperl.org>
Link: https://lore.kernel.org/r/32f27f4d8242e4d75f9a53f7e8f1f77483b08669.1589557526.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
The BCM2835 SPI driver uses devm_spi_register_controller() on bind.
As a consequence, on unbind, __device_release_driver() first invokes
bcm2835_spi_remove() before unregistering the SPI controller via
devres_release_all().
This order is incorrect: bcm2835_spi_remove() tears down the DMA
channels and turns off the SPI controller, including its interrupts
and clock. The SPI controller is thus no longer usable.
When the SPI controller is subsequently unregistered, it unbinds all
its slave devices. If their drivers need to access the SPI bus,
e.g. to quiesce their interrupts, unbinding will fail.
As a rule, devm_spi_register_controller() must not be used if the
->remove() hook performs teardown steps which shall be performed
after unbinding of slaves.
Fix by using the non-devm variant spi_register_controller(). Note that
the struct spi_controller as well as the driver-private data are not
freed until after bcm2835_spi_remove() has finished, so accessing them
is safe.
Fixes: 247263dba2 ("spi: bcm2835: use devm_spi_register_master()")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v3.13+
Link: https://lore.kernel.org/r/2397dd70cdbe95e0bc4da2b9fca0f31cb94e5aed.1589557526.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
When an SPI controller unregisters, it unbinds all its slave devices.
For this, their drivers may need to access the SPI bus, e.g. to quiesce
interrupts.
However since commit ffbbdd2132 ("spi: create a message queueing
infrastructure"), spi_destroy_queue() is executed before unbinding the
slaves. It sets ctlr->running = false, thereby preventing SPI bus
access and causing unbinding of slave devices to fail.
Fix by unbinding slaves before calling spi_destroy_queue().
Fixes: ffbbdd2132 ("spi: create a message queueing infrastructure")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v3.4+
Cc: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/8aaf9d44c153fe233b17bc2dec4eb679898d7e7b.1589557526.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Baikal-T1 SoC provides a DW DMA controller to perform low-speed peripherals
Mem-to-Dev and Dev-to-Mem transaction. This is also applicable to the DW
APB SSI devices embedded into the SoC. Currently the DMA-based transfers
are supported by the DW APB SPI driver only as a middle layer code for
Intel MID/Elkhart PCI devices. Seeing the same code can be used for normal
platform DMAC device we introduced a set of patches to fix it within this
series.
First of all we need to add the Tx and Rx DMA channels support into the DW
APB SSI binding. Then there are several fixes and cleanups provided as a
initial preparation for the Generic DMA support integration: add Tx/Rx
finish wait methods, clear DMAC register when done or stopped, Fix native
CS being unset, enable interrupts in accordance with DMA xfer mode,
discard static DW DMA slave structures, discard unused void priv pointer
and dma_width member of the dw_spi structure, provide the DMA Tx/Rx burst
length parametrisation and make sure it's optionally set in accordance
with the DMA max-burst capability.
In order to have the DW APB SSI MMIO driver working with DMA we need to
initialize the paddr field with the physical base address of the DW APB SSI
registers space. Then we unpin the Intel MID specific code from the
generic DMA one and placed it into the spi-dw-pci.c driver, which is a
better place for it anyway. After that the naming cleanups are performed
since the code is going to be used for a generic DMAC device. Finally the
Generic DMA initialization can be added to the generic version of the
DW APB SSI IP.
Last but not least we traditionally convert the legacy plain text-based
dt-binding file with yaml-based one and as a cherry on a cake replace
the manually written DebugFS registers read method with a ready-to-use
for the same purpose regset32 DebugFS interface usage.
This patchset is rebased and tested on the spi/for-next (5.7-rc5):
base-commit: fe9fce6b2cf3 ("Merge remote-tracking branch 'spi/for-5.8' into spi-next")
Co-developed-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Co-developed-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Maxim Kaurkin <Maxim.Kaurkin@baikalelectronics.ru>
Cc: Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>
Cc: Ekaterina Skachko <Ekaterina.Skachko@baikalelectronics.ru>
Cc: Vadim Vlasov <V.Vlasov@baikalelectronics.ru>
Cc: Alexey Kolotnikov <Alexey.Kolotnikov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Allison Randal <allison@lohutok.net>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Gareth Williams <gareth.williams.jx@renesas.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-spi@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
Changelog v2:
- Rebase on top of the spi repository for-next branch.
- Move bindings conversion patch to the tail of the series.
- Move fixes to the head of the series.
- Apply as many changes as possible to be applied the Generic DMA
functionality support is added and the spi-dw-mid is moved to the
spi-dw-dma driver.
- Discard patch "spi: dw: Fix dma_slave_config used partly uninitialized"
since the problem has already been fixed.
- Add new patch "spi: dw: Discard unused void priv pointer".
- Add new patch "spi: dw: Discard dma_width member of the dw_spi structure".
n_bytes member of the DW SPI data can be used instead.
- Build the DMA functionality into the DW APB SSI core if required instead
of creating a separate kernel module.
- Use conditional statement instead of the ternary operator in the ref
clock getter.
Serge Semin (19):
dt-bindings: spi: dw: Add Tx/Rx DMA properties
spi: dw: Add Tx/Rx finish wait methods to the MID DMA
spi: dw: Clear DMAC register when done or stopped
spi: dw: Fix native CS being unset
spi: dw: Enable interrupts in accordance with DMA xfer mode
spi: dw: Discard static DW DMA slave structures
spi: dw: Discard unused void priv pointer
spi: dw: Discard dma_width member of the dw_spi structure
spi: dw: Parameterize the DMA Rx/Tx burst length
spi: dw: Use DMA max burst to set the request thresholds
spi: dw: Initialize paddr in DW SPI MMIO private data
spi: dw: Fix Rx-only DMA transfers
spi: dw: Move Non-DMA code to the DW PCIe-SPI driver
spi: dw: Remove DW DMA code dependency from DW_DMAC_PCI
spi: dw: Add DW SPI DMA/PCI/MMIO dependency on the DW SPI core
spi: dw: Cleanup generic DW DMA code namings
spi: dw: Add DMA support to the DW SPI MMIO driver
spi: dw: Use regset32 DebugFS method to create regdump file
dt-bindings: spi: Convert DW SPI binding to DT schema
.../bindings/spi/snps,dw-apb-ssi.txt | 42 ---
.../bindings/spi/snps,dw-apb-ssi.yaml | 127 +++++++++
.../devicetree/bindings/spi/spi-dw.txt | 24 --
drivers/spi/Kconfig | 15 +-
drivers/spi/Makefile | 7 +-
drivers/spi/{spi-dw-mid.c => spi-dw-dma.c} | 257 ++++++++++--------
drivers/spi/spi-dw-mmio.c | 9 +-
drivers/spi/spi-dw-pci.c | 50 +++-
drivers/spi/spi-dw.c | 98 +++----
drivers/spi/spi-dw.h | 33 ++-
10 files changed, 405 insertions(+), 257 deletions(-)
delete mode 100644 Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.txt
create mode 100644 Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
delete mode 100644 Documentation/devicetree/bindings/spi/spi-dw.txt
rename drivers/spi/{spi-dw-mid.c => spi-dw-dma.c} (53%)
--
2.25.1
The original implementation set num_chipselect to ROCKCHIP_SPI_MAX_CS_NUM (2)
which seems wrong here. spi0 has 2 native cs, all others just one. With
enable and use of cs_gpiods / GPIO CS, its correct to set the num_chipselect
from the num-cs property and set max_native_cs with the define.
If num-cs is missing the default set to num_chipselect = 1.
Signed-off-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>
Link: https://lore.kernel.org/r/20200511083022.23678-4-chris.ruehl@gtsys.com.hk
Signed-off-by: Mark Brown <broonie@kernel.org>
Add support for spi slave mode in spi-rockchip. The register map has an entry
for it. If spi-slave is set in dts, set this corresponding bit and add to
mode_bits the SPI_NO_CS, allow slave mode without explicit CS use.
Slave abort function had been added.
Signed-off-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>
Link: https://lore.kernel.org/r/20200511083022.23678-3-chris.ruehl@gtsys.com.hk
Signed-off-by: Mark Brown <broonie@kernel.org>
Cleanup, move from the compatibily layer struct spi_master over
to struct spi_controller, and rename the related function calls.
Signed-off-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>
Link: https://lore.kernel.org/r/20200511083022.23678-2-chris.ruehl@gtsys.com.hk
Signed-off-by: Mark Brown <broonie@kernel.org>
If DMAC register is left uncleared any further DMAless transfers
may cause the DMAC hardware handshaking interface getting activated.
So the next DMA-based Rx/Tx transaction will be started right
after the dma_async_issue_pending() method is invoked even if no
DMATDLR/DMARDLR conditions are met. This at the same time may cause
the Tx/Rx FIFO buffers underrun/overrun. In order to fix this we
must clear DMAC register after a current DMA-based transaction is
finished.
Co-developed-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200515104758.6934-4-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
This field is used only for the DW SPI DMA code initialization, that's
why there were no problems with it being uninitialized in Dw SPI MMIO
driver. Since in a further patch we are going to introduce the DW SPI DMA
support in the MMIO version of the driver, lets set the field with the
physical address of the DW SPI controller registers region.
Co-developed-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Co-developed-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200515104758.6934-12-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit 6e0a32d6f3 ("spi: dw: Fix default polarity of native
chipselect") attempted to fix the problem when GPIO active-high
chip-select is utilized to communicate with some SPI slave. It fixed
the problem, but broke the normal native CS support. At the same time
the reversion commit ada9e3fcc1 ("spi: dw: Correct handling of native
chipselect") didn't solve the problem either, since it just inverted
the set_cs() polarity perception without taking into account that
CS-high might be applicable. Here is what is done to finally fix the
problem.
DW SPI controller demands any native CS being set in order to proceed
with data transfer. So in order to activate the SPI communications we
must set any bit in the Slave Select DW SPI controller register no
matter whether the platform requests the GPIO- or native CS. Preferably
it should be the bit corresponding to the SPI slave CS number. But
currently the dw_spi_set_cs() method activates the chip-select
only if the second argument is false. Since the second argument of the
set_cs callback is expected to be a boolean with "is-high" semantics
(actual chip-select pin state value), the bit in the DW SPI Slave
Select register will be set only if SPI core requests the driver
to set the CS in the low state. So this will work for active-low
GPIO-based CS case, and won't work for active-high CS setting
the bit when SPI core actually needs to deactivate the CS.
This commit fixes the problem for all described cases. So no matter
whether an SPI slave needs GPIO- or native-based CS with active-high
or low signal the corresponding bit will be set in SER.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Fixes: ada9e3fcc1 ("spi: dw: Correct handling of native chipselect")
Fixes: 6e0a32d6f3 ("spi: dw: Fix default polarity of native chipselect")
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200515104758.6934-5-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Use devm_platform_get_and_ioremap_resource() to simplify code instead of
platform_get_resource() and devm_ioremap_resource(). This also gets
the resource that the following code uses.
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Link: https://lore.kernel.org/r/1589185530-28170-2-git-send-email-hayashi.kunihiko@socionext.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This flag is superfluous in all cases where it's being used, i.e.
* ->can_dma() won't be called without dma_inited == 1
* DMA ->exit() callback can rely on txchan and rxchan variables
So, get rid of dma_inited flag.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200507115449.8093-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Generic DMA setup doesn't rely on certain type of DMA controller and thus
shouldn't use Intel Medfield settings, although it's harmless in this case.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200507115449.8093-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Elkhart Lake PSE SPI is capable to utilize PSE DMA engine which is described
in ACPI. With help of acpi-dma module the support becomes a generic one.
Thus, add Elkhart Lake PSE DMA support and generic DMA hooks in SPI DesignWare
driver.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200506153025.21441-8-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
In some cases, one of which is coming soon, we would like to have
a struct device pointer to request DMA channel. For this purpose
propagate it to ->dma_init() callback in DMA ops.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200506153025.21441-7-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
In order to prepare driver for the extension to support newer hardware,
add 'mfld' suffix to some related functions.
While here, move DMA parameters assignment under existing #ifdef
CONFIG_SPI_DW_MID_DMA.
There is no functional change intended.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200506153025.21441-6-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
There is no user of few headers without CONFIG_SPI_DW_MID_DMA being set.
Move them under condition.
While at it, remove unused slab.h there.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200506153025.21441-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
spi-dw-mid.c along with spi-dw.h are direct users of irqreturn.h
and nothing else is being used from interrupt.h. So, switch them
to use the former instead of latter one.
While here, move the header under #ifdef CONFIG_SPI_DW_MID_DMA
in spi-dw-mid.c.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200506153025.21441-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
