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authorLinus Torvalds <torvalds@linux-foundation.org>2022-10-08 01:56:34 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2022-10-08 01:56:34 +0300
commit416a2f4f91525fcdec821320bc4608cf012d418e (patch)
treea54e571a108fa801cca22409ef18db417ba7b43a /Documentation
parent62e6e5940c0c09433efa52d0fa9a11623a4704b2 (diff)
parentb957df98469240d459bcfae6904b36d6ecea9bee (diff)
downloadlinux-416a2f4f91525fcdec821320bc4608cf012d418e.tar.xz
Merge tag 'dmaengine-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine
Pull dmaengine updates from Vinod Koul: "New Support: - MT6795 SoC dma controller (AngeloGioacchino Del Regno) - qcom-adm controller yaml binding (Christian Marangi) - Renesas r8a779g0 dma controller yaml binding (Geert Uytterhoeven) - Qualcomm SM6350 GPI dma controller (Luca Weiss) Updates: - STM32 DMA-MDMA chaining support (Amelie Delaunay) - make hsu driver use managed resources (Andy Shevchenko) - the usual round of idxd driver updates (Dave Jiang & Jerry Snitselaar) - apple dma driver iommu and pd properties and remove use of devres for irqs (Janne Grunau & Martin PoviĊĦer) - device_synchronize support for Xilinx zynqmp driver (Swati Agarwal)" * tag 'dmaengine-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (60 commits) dmaengine: ioat: remove unused declarations in dma.h dmaengine: ti: k3-udma: Respond TX done if DMA_PREP_INTERRUPT is not requested dmaengine: zynqmp_dma: Add device_synchronize support dt-bindings: dma: add additional pbus reset to qcom,adm dt-bindings: dma: rework qcom,adm Documentation to yaml schema dt-bindings: dma: apple,admac: Add iommus and power-domains properties dmaengine: dw-edma: Remove runtime PM support dmaengine: idxd: add configuration for concurrent batch descriptor processing dmaengine: idxd: add configuration for concurrent work descriptor processing dmaengine: idxd: add WQ operation cap restriction support dmanegine: idxd: reformat opcap output to match bitmap_parse() input dmaengine: idxd: convert ats_dis to a wq flag dmaengine: ioat: stop mod_timer from resurrecting deleted timer in __cleanup() dmaengine: qcom-adm: fix wrong calling convention for prep_slave_sg dmaengine: qcom-adm: fix wrong sizeof config in slave_config dmaengine: ti: k3-psil: add additional TX threads for j721e dmaengine: ti: k3-psil: add additional TX threads for j7200 dmaengine: apple-admac: Trigger shared reset dmaengine: apple-admac: Do not use devres for IRQs dmaengine: ti: edma: Remove some unused functions ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/ABI/stable/sysfs-driver-dma-idxd35
-rw-r--r--Documentation/arm/index.rst1
-rw-r--r--Documentation/arm/stm32/stm32-dma-mdma-chaining.rst415
-rw-r--r--Documentation/devicetree/bindings/dma/apple,admac.yaml7
-rw-r--r--Documentation/devicetree/bindings/dma/arm,pl330.yaml6
-rw-r--r--Documentation/devicetree/bindings/dma/mediatek,uart-dma.yaml1
-rw-r--r--Documentation/devicetree/bindings/dma/qcom,adm.yaml99
-rw-r--r--Documentation/devicetree/bindings/dma/qcom,bam-dma.yaml8
-rw-r--r--Documentation/devicetree/bindings/dma/qcom,gpi.yaml1
-rw-r--r--Documentation/devicetree/bindings/dma/qcom_adm.txt61
-rw-r--r--Documentation/devicetree/bindings/dma/renesas,rcar-dmac.yaml1
-rw-r--r--Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt2
12 files changed, 571 insertions, 66 deletions
diff --git a/Documentation/ABI/stable/sysfs-driver-dma-idxd b/Documentation/ABI/stable/sysfs-driver-dma-idxd
index 0c2b613f2373..8e2c2c405db2 100644
--- a/Documentation/ABI/stable/sysfs-driver-dma-idxd
+++ b/Documentation/ABI/stable/sysfs-driver-dma-idxd
@@ -227,6 +227,17 @@ Contact: dmaengine@vger.kernel.org
Description: Indicate the number of retires for an enqcmds submission on a sharedwq.
A max value to set attribute is capped at 64.
+What: /sys/bus/dsa/devices/wq<m>.<n>/op_config
+Date: Sept 14, 2022
+KernelVersion: 6.0.0
+Contact: dmaengine@vger.kernel.org
+Description: Shows the operation capability bits displayed in bitmap format
+ presented by %*pb printk() output format specifier.
+ The attribute can be configured when the WQ is disabled in
+ order to configure the WQ to accept specific bits that
+ correlates to the operations allowed. It's visible only
+ on platforms that support the capability.
+
What: /sys/bus/dsa/devices/engine<m>.<n>/group_id
Date: Oct 25, 2019
KernelVersion: 5.6.0
@@ -255,3 +266,27 @@ Contact: dmaengine@vger.kernel.org
Description: Indicates the number of Read Buffers reserved for the use of
engines in the group. See DSA spec v1.2 9.2.18 GRPCFG Read Buffers
Reserved.
+
+What: /sys/bus/dsa/devices/group<m>.<n>/desc_progress_limit
+Date: Sept 14, 2022
+KernelVersion: 6.0.0
+Contact: dmaengine@vger.kernel.org
+Description: Allows control of the number of work descriptors that can be
+ concurrently processed by an engine in the group as a fraction
+ of the Maximum Work Descriptors in Progress value specified in
+ the ENGCAP register. The acceptable values are 0 (default),
+ 1 (1/2 of max value), 2 (1/4 of the max value), and 3 (1/8 of
+ the max value). It's visible only on platforms that support
+ the capability.
+
+What: /sys/bus/dsa/devices/group<m>.<n>/batch_progress_limit
+Date: Sept 14, 2022
+KernelVersion: 6.0.0
+Contact: dmaengine@vger.kernel.org
+Description: Allows control of the number of batch descriptors that can be
+ concurrently processed by an engine in the group as a fraction
+ of the Maximum Batch Descriptors in Progress value specified in
+ the ENGCAP register. The acceptable values are 0 (default),
+ 1 (1/2 of max value), 2 (1/4 of the max value), and 3 (1/8 of
+ the max value). It's visible only on platforms that support
+ the capability.
diff --git a/Documentation/arm/index.rst b/Documentation/arm/index.rst
index 495ada7915e1..8c636d4a061f 100644
--- a/Documentation/arm/index.rst
+++ b/Documentation/arm/index.rst
@@ -59,6 +59,7 @@ SoC-specific documents
stm32/stm32f429-overview
stm32/stm32mp13-overview
stm32/stm32mp157-overview
+ stm32/stm32-dma-mdma-chaining
sunxi
diff --git a/Documentation/arm/stm32/stm32-dma-mdma-chaining.rst b/Documentation/arm/stm32/stm32-dma-mdma-chaining.rst
new file mode 100644
index 000000000000..2945e0e33104
--- /dev/null
+++ b/Documentation/arm/stm32/stm32-dma-mdma-chaining.rst
@@ -0,0 +1,415 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=======================
+STM32 DMA-MDMA chaining
+=======================
+
+
+Introduction
+------------
+
+ This document describes the STM32 DMA-MDMA chaining feature. But before going
+ further, let's introduce the peripherals involved.
+
+ To offload data transfers from the CPU, STM32 microprocessors (MPUs) embed
+ direct memory access controllers (DMA).
+
+ STM32MP1 SoCs embed both STM32 DMA and STM32 MDMA controllers. STM32 DMA
+ request routing capabilities are enhanced by a DMA request multiplexer
+ (STM32 DMAMUX).
+
+ **STM32 DMAMUX**
+
+ STM32 DMAMUX routes any DMA request from a given peripheral to any STM32 DMA
+ controller (STM32MP1 counts two STM32 DMA controllers) channels.
+
+ **STM32 DMA**
+
+ STM32 DMA is mainly used to implement central data buffer storage (usually in
+ the system SRAM) for different peripheral. It can access external RAMs but
+ without the ability to generate convenient burst transfer ensuring the best
+ load of the AXI.
+
+ **STM32 MDMA**
+
+ STM32 MDMA (Master DMA) is mainly used to manage direct data transfers between
+ RAM data buffers without CPU intervention. It can also be used in a
+ hierarchical structure that uses STM32 DMA as first level data buffer
+ interfaces for AHB peripherals, while the STM32 MDMA acts as a second level
+ DMA with better performance. As a AXI/AHB master, STM32 MDMA can take control
+ of the AXI/AHB bus.
+
+
+Principles
+----------
+
+ STM32 DMA-MDMA chaining feature relies on the strengths of STM32 DMA and
+ STM32 MDMA controllers.
+
+ STM32 DMA has a circular Double Buffer Mode (DBM). At each end of transaction
+ (when DMA data counter - DMA_SxNDTR - reaches 0), the memory pointers
+ (configured with DMA_SxSM0AR and DMA_SxM1AR) are swapped and the DMA data
+ counter is automatically reloaded. This allows the SW or the STM32 MDMA to
+ process one memory area while the second memory area is being filled/used by
+ the STM32 DMA transfer.
+
+ With STM32 MDMA linked-list mode, a single request initiates the data array
+ (collection of nodes) to be transferred until the linked-list pointer for the
+ channel is null. The channel transfer complete of the last node is the end of
+ transfer, unless first and last nodes are linked to each other, in such a
+ case, the linked-list loops on to create a circular MDMA transfer.
+
+ STM32 MDMA has direct connections with STM32 DMA. This enables autonomous
+ communication and synchronization between peripherals, thus saving CPU
+ resources and bus congestion. Transfer Complete signal of STM32 DMA channel
+ can triggers STM32 MDMA transfer. STM32 MDMA can clear the request generated
+ by the STM32 DMA by writing to its Interrupt Clear register (whose address is
+ stored in MDMA_CxMAR, and bit mask in MDMA_CxMDR).
+
+ .. table:: STM32 MDMA interconnect table with STM32 DMA
+
+ +--------------+----------------+-----------+------------+
+ | STM32 DMAMUX | STM32 DMA | STM32 DMA | STM32 MDMA |
+ | channels | channels | Transfer | request |
+ | | | complete | |
+ | | | signal | |
+ +==============+================+===========+============+
+ | Channel *0* | DMA1 channel 0 | dma1_tcf0 | *0x00* |
+ +--------------+----------------+-----------+------------+
+ | Channel *1* | DMA1 channel 1 | dma1_tcf1 | *0x01* |
+ +--------------+----------------+-----------+------------+
+ | Channel *2* | DMA1 channel 2 | dma1_tcf2 | *0x02* |
+ +--------------+----------------+-----------+------------+
+ | Channel *3* | DMA1 channel 3 | dma1_tcf3 | *0x03* |
+ +--------------+----------------+-----------+------------+
+ | Channel *4* | DMA1 channel 4 | dma1_tcf4 | *0x04* |
+ +--------------+----------------+-----------+------------+
+ | Channel *5* | DMA1 channel 5 | dma1_tcf5 | *0x05* |
+ +--------------+----------------+-----------+------------+
+ | Channel *6* | DMA1 channel 6 | dma1_tcf6 | *0x06* |
+ +--------------+----------------+-----------+------------+
+ | Channel *7* | DMA1 channel 7 | dma1_tcf7 | *0x07* |
+ +--------------+----------------+-----------+------------+
+ | Channel *8* | DMA2 channel 0 | dma2_tcf0 | *0x08* |
+ +--------------+----------------+-----------+------------+
+ | Channel *9* | DMA2 channel 1 | dma2_tcf1 | *0x09* |
+ +--------------+----------------+-----------+------------+
+ | Channel *10* | DMA2 channel 2 | dma2_tcf2 | *0x0A* |
+ +--------------+----------------+-----------+------------+
+ | Channel *11* | DMA2 channel 3 | dma2_tcf3 | *0x0B* |
+ +--------------+----------------+-----------+------------+
+ | Channel *12* | DMA2 channel 4 | dma2_tcf4 | *0x0C* |
+ +--------------+----------------+-----------+------------+
+ | Channel *13* | DMA2 channel 5 | dma2_tcf5 | *0x0D* |
+ +--------------+----------------+-----------+------------+
+ | Channel *14* | DMA2 channel 6 | dma2_tcf6 | *0x0E* |
+ +--------------+----------------+-----------+------------+
+ | Channel *15* | DMA2 channel 7 | dma2_tcf7 | *0x0F* |
+ +--------------+----------------+-----------+------------+
+
+ STM32 DMA-MDMA chaining feature then uses a SRAM buffer. STM32MP1 SoCs embed
+ three fast access static internal RAMs of various size, used for data storage.
+ Due to STM32 DMA legacy (within microcontrollers), STM32 DMA performances are
+ bad with DDR, while they are optimal with SRAM. Hence the SRAM buffer used
+ between STM32 DMA and STM32 MDMA. This buffer is split in two equal periods
+ and STM32 DMA uses one period while STM32 MDMA uses the other period
+ simultaneously.
+ ::
+
+ dma[1:2]-tcf[0:7]
+ .----------------.
+ ____________ ' _________ V____________
+ | STM32 DMA | / __|>_ \ | STM32 MDMA |
+ |------------| | / \ | |------------|
+ | DMA_SxM0AR |<=>| | SRAM | |<=>| []-[]...[] |
+ | DMA_SxM1AR | | \_____/ | | |
+ |____________| \___<|____/ |____________|
+
+ STM32 DMA-MDMA chaining uses (struct dma_slave_config).peripheral_config to
+ exchange the parameters needed to configure MDMA. These parameters are
+ gathered into a u32 array with three values:
+
+ * the STM32 MDMA request (which is actually the DMAMUX channel ID),
+ * the address of the STM32 DMA register to clear the Transfer Complete
+ interrupt flag,
+ * the mask of the Transfer Complete interrupt flag of the STM32 DMA channel.
+
+Device Tree updates for STM32 DMA-MDMA chaining support
+-------------------------------------------------------
+
+ **1. Allocate a SRAM buffer**
+
+ SRAM device tree node is defined in SoC device tree. You can refer to it in
+ your board device tree to define your SRAM pool.
+ ::
+
+ &sram {
+ my_foo_device_dma_pool: dma-sram@0 {
+ reg = <0x0 0x1000>;
+ };
+ };
+
+ Be careful of the start index, in case there are other SRAM consumers.
+ Define your pool size strategically: to optimise chaining, the idea is that
+ STM32 DMA and STM32 MDMA can work simultaneously, on each buffer of the
+ SRAM.
+ If the SRAM period is greater than the expected DMA transfer, then STM32 DMA
+ and STM32 MDMA will work sequentially instead of simultaneously. It is not a
+ functional issue but it is not optimal.
+
+ Don't forget to refer to your SRAM pool in your device node. You need to
+ define a new property.
+ ::
+
+ &my_foo_device {
+ ...
+ my_dma_pool = &my_foo_device_dma_pool;
+ };
+
+ Then get this SRAM pool in your foo driver and allocate your SRAM buffer.
+
+ **2. Allocate a STM32 DMA channel and a STM32 MDMA channel**
+
+ You need to define an extra channel in your device tree node, in addition to
+ the one you should already have for "classic" DMA operation.
+
+ This new channel must be taken from STM32 MDMA channels, so, the phandle of
+ the DMA controller to use is the MDMA controller's one.
+ ::
+
+ &my_foo_device {
+ [...]
+ my_dma_pool = &my_foo_device_dma_pool;
+ dmas = <&dmamux1 ...>, // STM32 DMA channel
+ <&mdma1 0 0x3 0x1200000a 0 0>; // + STM32 MDMA channel
+ };
+
+ Concerning STM32 MDMA bindings:
+
+ 1. The request line number : whatever the value here, it will be overwritten
+ by MDMA driver with the STM32 DMAMUX channel ID passed through
+ (struct dma_slave_config).peripheral_config
+
+ 2. The priority level : choose Very High (0x3) so that your channel will
+ take priority other the other during request arbitration
+
+ 3. A 32bit mask specifying the DMA channel configuration : source and
+ destination address increment, block transfer with 128 bytes per single
+ transfer
+
+ 4. The 32bit value specifying the register to be used to acknowledge the
+ request: it will be overwritten by MDMA driver, with the DMA channel
+ interrupt flag clear register address passed through
+ (struct dma_slave_config).peripheral_config
+
+ 5. The 32bit mask specifying the value to be written to acknowledge the
+ request: it will be overwritten by MDMA driver, with the DMA channel
+ Transfer Complete flag passed through
+ (struct dma_slave_config).peripheral_config
+
+Driver updates for STM32 DMA-MDMA chaining support in foo driver
+----------------------------------------------------------------
+
+ **0. (optional) Refactor the original sg_table if dmaengine_prep_slave_sg()**
+
+ In case of dmaengine_prep_slave_sg(), the original sg_table can't be used as
+ is. Two new sg_tables must be created from the original one. One for
+ STM32 DMA transfer (where memory address targets now the SRAM buffer instead
+ of DDR buffer) and one for STM32 MDMA transfer (where memory address targets
+ the DDR buffer).
+
+ The new sg_list items must fit SRAM period length. Here is an example for
+ DMA_DEV_TO_MEM:
+ ::
+
+ /*
+ * Assuming sgl and nents, respectively the initial scatterlist and its
+ * length.
+ * Assuming sram_dma_buf and sram_period, respectively the memory
+ * allocated from the pool for DMA usage, and the length of the period,
+ * which is half of the sram_buf size.
+ */
+ struct sg_table new_dma_sgt, new_mdma_sgt;
+ struct scatterlist *s, *_sgl;
+ dma_addr_t ddr_dma_buf;
+ u32 new_nents = 0, len;
+ int i;
+
+ /* Count the number of entries needed */
+ for_each_sg(sgl, s, nents, i)
+ if (sg_dma_len(s) > sram_period)
+ new_nents += DIV_ROUND_UP(sg_dma_len(s), sram_period);
+ else
+ new_nents++;
+
+ /* Create sg table for STM32 DMA channel */
+ ret = sg_alloc_table(&new_dma_sgt, new_nents, GFP_ATOMIC);
+ if (ret)
+ dev_err(dev, "DMA sg table alloc failed\n");
+
+ for_each_sg(new_dma_sgt.sgl, s, new_dma_sgt.nents, i) {
+ _sgl = sgl;
+ sg_dma_len(s) = min(sg_dma_len(_sgl), sram_period);
+ /* Targets the beginning = first half of the sram_buf */
+ s->dma_address = sram_buf;
+ /*
+ * Targets the second half of the sram_buf
+ * for odd indexes of the item of the sg_list
+ */
+ if (i & 1)
+ s->dma_address += sram_period;
+ }
+
+ /* Create sg table for STM32 MDMA channel */
+ ret = sg_alloc_table(&new_mdma_sgt, new_nents, GFP_ATOMIC);
+ if (ret)
+ dev_err(dev, "MDMA sg_table alloc failed\n");
+
+ _sgl = sgl;
+ len = sg_dma_len(sgl);
+ ddr_dma_buf = sg_dma_address(sgl);
+ for_each_sg(mdma_sgt.sgl, s, mdma_sgt.nents, i) {
+ size_t bytes = min_t(size_t, len, sram_period);
+
+ sg_dma_len(s) = bytes;
+ sg_dma_address(s) = ddr_dma_buf;
+ len -= bytes;
+
+ if (!len && sg_next(_sgl)) {
+ _sgl = sg_next(_sgl);
+ len = sg_dma_len(_sgl);
+ ddr_dma_buf = sg_dma_address(_sgl);
+ } else {
+ ddr_dma_buf += bytes;
+ }
+ }
+
+ Don't forget to release these new sg_tables after getting the descriptors
+ with dmaengine_prep_slave_sg().
+
+ **1. Set controller specific parameters**
+
+ First, use dmaengine_slave_config() with a struct dma_slave_config to
+ configure STM32 DMA channel. You just have to take care of DMA addresses,
+ the memory address (depending on the transfer direction) must point on your
+ SRAM buffer, and set (struct dma_slave_config).peripheral_size != 0.
+
+ STM32 DMA driver will check (struct dma_slave_config).peripheral_size to
+ determine if chaining is being used or not. If it is used, then STM32 DMA
+ driver fills (struct dma_slave_config).peripheral_config with an array of
+ three u32 : the first one containing STM32 DMAMUX channel ID, the second one
+ the channel interrupt flag clear register address, and the third one the
+ channel Transfer Complete flag mask.
+
+ Then, use dmaengine_slave_config with another struct dma_slave_config to
+ configure STM32 MDMA channel. Take care of DMA addresses, the device address
+ (depending on the transfer direction) must point on your SRAM buffer, and
+ the memory address must point to the buffer originally used for "classic"
+ DMA operation. Use the previous (struct dma_slave_config).peripheral_size
+ and .peripheral_config that have been updated by STM32 DMA driver, to set
+ (struct dma_slave_config).peripheral_size and .peripheral_config of the
+ struct dma_slave_config to configure STM32 MDMA channel.
+ ::
+
+ struct dma_slave_config dma_conf;
+ struct dma_slave_config mdma_conf;
+
+ memset(&dma_conf, 0, sizeof(dma_conf));
+ [...]
+ config.direction = DMA_DEV_TO_MEM;
+ config.dst_addr = sram_dma_buf; // SRAM buffer
+ config.peripheral_size = 1; // peripheral_size != 0 => chaining
+
+ dmaengine_slave_config(dma_chan, &dma_config);
+
+ memset(&mdma_conf, 0, sizeof(mdma_conf));
+ config.direction = DMA_DEV_TO_MEM;
+ mdma_conf.src_addr = sram_dma_buf; // SRAM buffer
+ mdma_conf.dst_addr = rx_dma_buf; // original memory buffer
+ mdma_conf.peripheral_size = dma_conf.peripheral_size; // <- dma_conf
+ mdma_conf.peripheral_config = dma_config.peripheral_config; // <- dma_conf
+
+ dmaengine_slave_config(mdma_chan, &mdma_conf);
+
+ **2. Get a descriptor for STM32 DMA channel transaction**
+
+ In the same way you get your descriptor for your "classic" DMA operation,
+ you just have to replace the original sg_list (in case of
+ dmaengine_prep_slave_sg()) with the new sg_list using SRAM buffer, or to
+ replace the original buffer address, length and period (in case of
+ dmaengine_prep_dma_cyclic()) with the new SRAM buffer.
+
+ **3. Get a descriptor for STM32 MDMA channel transaction**
+
+ If you previously get descriptor (for STM32 DMA) with
+
+ * dmaengine_prep_slave_sg(), then use dmaengine_prep_slave_sg() for
+ STM32 MDMA;
+ * dmaengine_prep_dma_cyclic(), then use dmaengine_prep_dma_cyclic() for
+ STM32 MDMA.
+
+ Use the new sg_list using SRAM buffer (in case of dmaengine_prep_slave_sg())
+ or, depending on the transfer direction, either the original DDR buffer (in
+ case of DMA_DEV_TO_MEM) or the SRAM buffer (in case of DMA_MEM_TO_DEV), the
+ source address being previously set with dmaengine_slave_config().
+
+ **4. Submit both transactions**
+
+ Before submitting your transactions, you may need to define on which
+ descriptor you want a callback to be called at the end of the transfer
+ (dmaengine_prep_slave_sg()) or the period (dmaengine_prep_dma_cyclic()).
+ Depending on the direction, set the callback on the descriptor that finishes
+ the overal transfer:
+
+ * DMA_DEV_TO_MEM: set the callback on the "MDMA" descriptor
+ * DMA_MEM_TO_DEV: set the callback on the "DMA" descriptor
+
+ Then, submit the descriptors whatever the order, with dmaengine_tx_submit().
+
+ **5. Issue pending requests (and wait for callback notification)**
+
+ As STM32 MDMA channel transfer is triggered by STM32 DMA, you must issue
+ STM32 MDMA channel before STM32 DMA channel.
+
+ If any, your callback will be called to warn you about the end of the overal
+ transfer or the period completion.
+
+ Don't forget to terminate both channels. STM32 DMA channel is configured in
+ cyclic Double-Buffer mode so it won't be disabled by HW, you need to terminate
+ it. STM32 MDMA channel will be stopped by HW in case of sg transfer, but not
+ in case of cyclic transfer. You can terminate it whatever the kind of transfer.
+
+ **STM32 DMA-MDMA chaining DMA_MEM_TO_DEV special case**
+
+ STM32 DMA-MDMA chaining in DMA_MEM_TO_DEV is a special case. Indeed, the
+ STM32 MDMA feeds the SRAM buffer with the DDR data, and the STM32 DMA reads
+ data from SRAM buffer. So some data (the first period) have to be copied in
+ SRAM buffer when the STM32 DMA starts to read.
+
+ A trick could be pausing the STM32 DMA channel (that will raise a Transfer
+ Complete signal, triggering the STM32 MDMA channel), but the first data read
+ by the STM32 DMA could be "wrong". The proper way is to prepare the first SRAM
+ period with dmaengine_prep_dma_memcpy(). Then this first period should be
+ "removed" from the sg or the cyclic transfer.
+
+ Due to this complexity, rather use the STM32 DMA-MDMA chaining for
+ DMA_DEV_TO_MEM and keep the "classic" DMA usage for DMA_MEM_TO_DEV, unless
+ you're not afraid.
+
+Resources
+---------
+
+ Application note, datasheet and reference manual are available on ST website
+ (STM32MP1_).
+
+ Dedicated focus on three application notes (AN5224_, AN4031_ & AN5001_)
+ dealing with STM32 DMAMUX, STM32 DMA and STM32 MDMA.
+
+.. _STM32MP1: https://www.st.com/en/microcontrollers-microprocessors/stm32mp1-series.html
+.. _AN5224: https://www.st.com/resource/en/application_note/an5224-stm32-dmamux-the-dma-request-router-stmicroelectronics.pdf
+.. _AN4031: https://www.st.com/resource/en/application_note/dm00046011-using-the-stm32f2-stm32f4-and-stm32f7-series-dma-controller-stmicroelectronics.pdf
+.. _AN5001: https://www.st.com/resource/en/application_note/an5001-stm32cube-expansion-package-for-stm32h7-series-mdma-stmicroelectronics.pdf
+
+:Authors:
+
+- Amelie Delaunay <amelie.delaunay@foss.st.com> \ No newline at end of file
diff --git a/Documentation/devicetree/bindings/dma/apple,admac.yaml b/Documentation/devicetree/bindings/dma/apple,admac.yaml
index bdc8c129c4f5..3b1e667f7ea0 100644
--- a/Documentation/devicetree/bindings/dma/apple,admac.yaml
+++ b/Documentation/devicetree/bindings/dma/apple,admac.yaml
@@ -49,6 +49,13 @@ properties:
in an interrupts-extended list the disconnected positions will contain
an empty phandle reference <0>.
+ iommus:
+ minItems: 1
+ maxItems: 2
+
+ power-domains:
+ maxItems: 1
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/dma/arm,pl330.yaml b/Documentation/devicetree/bindings/dma/arm,pl330.yaml
index 2bec69b308f8..4a3dd6f5309b 100644
--- a/Documentation/devicetree/bindings/dma/arm,pl330.yaml
+++ b/Documentation/devicetree/bindings/dma/arm,pl330.yaml
@@ -55,6 +55,12 @@ properties:
dma-coherent: true
+ iommus:
+ minItems: 1
+ maxItems: 9
+ description: Up to 1 IOMMU entry per DMA channel for writes and 1
+ IOMMU entry for reads.
+
power-domains:
maxItems: 1
diff --git a/Documentation/devicetree/bindings/dma/mediatek,uart-dma.yaml b/Documentation/devicetree/bindings/dma/mediatek,uart-dma.yaml
index 19ea8dcbcbce..9ab4d81ead35 100644
--- a/Documentation/devicetree/bindings/dma/mediatek,uart-dma.yaml
+++ b/Documentation/devicetree/bindings/dma/mediatek,uart-dma.yaml
@@ -22,6 +22,7 @@ properties:
- items:
- enum:
- mediatek,mt2712-uart-dma
+ - mediatek,mt6795-uart-dma
- mediatek,mt8365-uart-dma
- mediatek,mt8516-uart-dma
- const: mediatek,mt6577-uart-dma
diff --git a/Documentation/devicetree/bindings/dma/qcom,adm.yaml b/Documentation/devicetree/bindings/dma/qcom,adm.yaml
new file mode 100644
index 000000000000..6a9d7bc74aff
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/qcom,adm.yaml
@@ -0,0 +1,99 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/dma/qcom,adm.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm ADM DMA Controller
+
+maintainers:
+ - Christian Marangi <ansuelsmth@gmail.com>
+ - Bjorn Andersson <bjorn.andersson@linaro.org>
+
+description: |
+ QCOM ADM DMA controller provides DMA capabilities for
+ peripheral buses such as NAND and SPI.
+
+properties:
+ compatible:
+ const: qcom,adm
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ "#dma-cells":
+ const: 1
+
+ clocks:
+ items:
+ - description: phandle to the core clock
+ - description: phandle to the iface clock
+
+ clock-names:
+ items:
+ - const: core
+ - const: iface
+
+ resets:
+ items:
+ - description: phandle to the clk reset
+ - description: phandle to the pbus reset
+ - description: phandle to the c0 reset
+ - description: phandle to the c1 reset
+ - description: phandle to the c2 reset
+
+ reset-names:
+ items:
+ - const: clk
+ - const: pbus
+ - const: c0
+ - const: c1
+ - const: c2
+
+ qcom,ee:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: indicates the security domain identifier used in the secure world.
+ minimum: 0
+ maximum: 255
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - "#dma-cells"
+ - clocks
+ - clock-names
+ - resets
+ - reset-names
+ - qcom,ee
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/clock/qcom,gcc-ipq806x.h>
+ #include <dt-bindings/reset/qcom,gcc-ipq806x.h>
+
+ adm_dma: dma-controller@18300000 {
+ compatible = "qcom,adm";
+ reg = <0x18300000 0x100000>;
+ interrupts = <0 170 0>;
+ #dma-cells = <1>;
+
+ clocks = <&gcc ADM0_CLK>,
+ <&gcc ADM0_PBUS_CLK>;
+ clock-names = "core", "iface";
+
+ resets = <&gcc ADM0_RESET>,
+ <&gcc ADM0_PBUS_RESET>,
+ <&gcc ADM0_C0_RESET>,
+ <&gcc ADM0_C1_RESET>,
+ <&gcc ADM0_C2_RESET>;
+ reset-names = "clk", "pbus", "c0", "c1", "c2";
+ qcom,ee = <0>;
+ };
+
+...
diff --git a/Documentation/devicetree/bindings/dma/qcom,bam-dma.yaml b/Documentation/devicetree/bindings/dma/qcom,bam-dma.yaml
index 9bf3a1b164f1..003098caf709 100644
--- a/Documentation/devicetree/bindings/dma/qcom,bam-dma.yaml
+++ b/Documentation/devicetree/bindings/dma/qcom,bam-dma.yaml
@@ -8,7 +8,7 @@ title: Qualcomm Technologies Inc BAM DMA controller
maintainers:
- Andy Gross <agross@kernel.org>
- - Bjorn Andersson <bjorn.andersson@linaro.org>
+ - Bjorn Andersson <andersson@kernel.org>
allOf:
- $ref: "dma-controller.yaml#"
@@ -20,7 +20,7 @@ properties:
- qcom,bam-v1.3.0
# MSM8974, APQ8074 and APQ8084
- qcom,bam-v1.4.0
- # MSM8916
+ # MSM8916 and SDM845
- qcom,bam-v1.7.0
clocks:
@@ -90,8 +90,8 @@ examples:
dma-controller@f9944000 {
compatible = "qcom,bam-v1.4.0";
- reg = <0xf9944000 0x15000>;
- interrupts = <GIC_SPI 94 IRQ_TYPE_LEVEL_HIGH>;
+ reg = <0xf9944000 0x19000>;
+ interrupts = <GIC_SPI 239 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&gcc GCC_BLSP2_AHB_CLK>;
clock-names = "bam_clk";
#dma-cells = <1>;
diff --git a/Documentation/devicetree/bindings/dma/qcom,gpi.yaml b/Documentation/devicetree/bindings/dma/qcom,gpi.yaml
index 7d2fc4eb5530..eabf8a76d3a0 100644
--- a/Documentation/devicetree/bindings/dma/qcom,gpi.yaml
+++ b/Documentation/devicetree/bindings/dma/qcom,gpi.yaml
@@ -21,6 +21,7 @@ properties:
enum:
- qcom,sc7280-gpi-dma
- qcom,sdm845-gpi-dma
+ - qcom,sm6350-gpi-dma
- qcom,sm8150-gpi-dma
- qcom,sm8250-gpi-dma
- qcom,sm8350-gpi-dma
diff --git a/Documentation/devicetree/bindings/dma/qcom_adm.txt b/Documentation/devicetree/bindings/dma/qcom_adm.txt
deleted file mode 100644
index 9d3b2f917b7b..000000000000
--- a/Documentation/devicetree/bindings/dma/qcom_adm.txt
+++ /dev/null
@@ -1,61 +0,0 @@
-QCOM ADM DMA Controller
-
-Required properties:
-- compatible: must contain "qcom,adm" for IPQ/APQ8064 and MSM8960
-- reg: Address range for DMA registers
-- interrupts: Should contain one interrupt shared by all channels
-- #dma-cells: must be <2>. First cell denotes the channel number. Second cell
- denotes CRCI (client rate control interface) flow control assignment.
-- clocks: Should contain the core clock and interface clock.
-- clock-names: Must contain "core" for the core clock and "iface" for the
- interface clock.
-- resets: Must contain an entry for each entry in reset names.
-- reset-names: Must include the following entries:
- - clk
- - c0
- - c1
- - c2
-- qcom,ee: indicates the security domain identifier used in the secure world.
-
-Example:
- adm_dma: dma@18300000 {
- compatible = "qcom,adm";
- reg = <0x18300000 0x100000>;
- interrupts = <0 170 0>;
- #dma-cells = <2>;
-
- clocks = <&gcc ADM0_CLK>, <&gcc ADM0_PBUS_CLK>;
- clock-names = "core", "iface";
-
- resets = <&gcc ADM0_RESET>,
- <&gcc ADM0_C0_RESET>,
- <&gcc ADM0_C1_RESET>,
- <&gcc ADM0_C2_RESET>;
- reset-names = "clk", "c0", "c1", "c2";
- qcom,ee = <0>;
- };
-
-DMA clients must use the format descripted in the dma.txt file, using a three
-cell specifier for each channel.
-
-Each dmas request consists of 3 cells:
- 1. phandle pointing to the DMA controller
- 2. channel number
- 3. CRCI assignment, if applicable. If no CRCI flow control is required, use 0.
- The CRCI is used for flow control. It identifies the peripheral device that
- is the source/destination for the transferred data.
-
-Example:
-
- spi4: spi@1a280000 {
- spi-max-frequency = <50000000>;
-
- pinctrl-0 = <&spi_pins>;
- pinctrl-names = "default";
-
- cs-gpios = <&qcom_pinmux 20 0>;
-
- dmas = <&adm_dma 6 9>,
- <&adm_dma 5 10>;
- dma-names = "rx", "tx";
- };
diff --git a/Documentation/devicetree/bindings/dma/renesas,rcar-dmac.yaml b/Documentation/devicetree/bindings/dma/renesas,rcar-dmac.yaml
index 7202cd68e759..89b591a05bce 100644
--- a/Documentation/devicetree/bindings/dma/renesas,rcar-dmac.yaml
+++ b/Documentation/devicetree/bindings/dma/renesas,rcar-dmac.yaml
@@ -45,6 +45,7 @@ properties:
- enum:
- renesas,dmac-r8a779a0 # R-Car V3U
- renesas,dmac-r8a779f0 # R-Car S4-8
+ - renesas,dmac-r8a779g0 # R-Car V4H
- const: renesas,rcar-gen4-dmac # R-Car Gen4
reg: true
diff --git a/Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt b/Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt
index b849a1ed389d..47e477cce6d2 100644
--- a/Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt
+++ b/Documentation/devicetree/bindings/dma/ti-dma-crossbar.txt
@@ -4,7 +4,7 @@ Required properties:
- compatible: "ti,dra7-dma-crossbar" for DRA7xx DMA crossbar
"ti,am335x-edma-crossbar" for AM335x and AM437x
- reg: Memory map for accessing module
-- #dma-cells: Should be set to to match with the DMA controller's dma-cells
+- #dma-cells: Should be set to match with the DMA controller's dma-cells
for ti,dra7-dma-crossbar and <3> for ti,am335x-edma-crossbar.
- dma-requests: Number of DMA requests the crossbar can receive
- dma-masters: phandle pointing to the DMA controller