Commit graph

5469 commits

Author SHA1 Message Date
Tudor Ambarus
c47e6403fa dmaengine: at_hdmac: Check return code of dma_async_device_register
dma_async_device_register() can fail, check the return code and display an
error.

Fixes: dc78baa2b9 ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller")
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-16-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:57 +05:30
Tudor Ambarus
28cbe5a0a4 dmaengine: at_hdmac: Fix impossible condition
The iterator can not be greater than ATC_MAX_DSCR_TRIALS, as the for loop
will stop when i == ATC_MAX_DSCR_TRIALS. While here, use the common "i"
name for the iterator.

Fixes: 93dce3a643 ("dmaengine: at_hdmac: fix residue computation")
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-15-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:57 +05:30
Tudor Ambarus
580ee84405 dmaengine: at_hdmac: Don't allow CPU to reorder channel enable
at_hdmac uses __raw_writel for register writes. In the absence of a
barrier, the CPU may reorder the register operations.
Introduce a write memory barrier so that the CPU does not reorder the
channel enable, thus the start of the transfer, without making sure that
all the pre-required register fields are already written.

Fixes: dc78baa2b9 ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-14-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:57 +05:30
Tudor Ambarus
ef2cb4f0ce dmaengine: at_hdmac: Fix completion of unissued descriptor in case of errors
In case the controller detected an error, the code took the chance to move
all the queued (submitted) descriptors to the active (issued) list. This
was wrong as if there were any descriptors in the submitted list they were
moved to the issued list without actually issuing them to the controller,
thus a completion could be raised without even fireing the descriptor.

Fixes: dc78baa2b9 ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-13-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:57 +05:30
Tudor Ambarus
ba2423633b dmaengine: at_hdmac: Fix descriptor handling when issuing it to hardware
As it was before, the descriptor was issued to the hardware without adding
it to the active (issued) list. This could result in a completion of other
descriptor, or/and in the descriptor never being completed.

Fixes: dc78baa2b9 ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-12-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:57 +05:30
Tudor Ambarus
03ed9ba357 dmaengine: at_hdmac: Fix concurrency over the active list
The tasklet (atc_advance_work()) did not held the channel lock when
retrieving the first active descriptor, causing concurrency problems if
issue_pending() was called in between. If issue_pending() was called
exactly after the lock was released in the tasklet (atc_advance_work()),
atc_chain_complete() could complete a descriptor for which the controller
has not yet raised an interrupt.

Fixes: dc78baa2b9 ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-11-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:57 +05:30
Tudor Ambarus
6ba826cbb5 dmaengine: at_hdmac: Free the memset buf without holding the chan lock
There's no need to hold the channel lock when freeing the memset buf, as
the operation has already completed. Free the memset buf without holding
the channel lock.

Fixes: 4d112426c3 ("dmaengine: hdmac: Add memset capabilities")
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-10-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:57 +05:30
Tudor Ambarus
06988949df dmaengine: at_hdmac: Fix concurrency over descriptor
The descriptor was added to the free_list before calling the callback,
which could result in reissuing of the same descriptor and calling of a
single callback for both. Move the decriptor to the free list after the
callback is invoked.

Fixes: dc78baa2b9 ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-9-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:57 +05:30
Tudor Ambarus
c6babed879 dmaengine: at_hdmac: Fix concurrency problems by removing atc_complete_all()
atc_complete_all() had concurrency bugs, thus remove it:
1/ atc_complete_all() in its entirety was buggy, as when the atchan->queue
list (the one that contains descriptors that are not yet issued to the
hardware) contained descriptors, it fired just the first from the
atchan->queue, but moved all the desc from atchan->queue to
atchan->active_list and considered them all as fired. This could result in
calling the completion of a descriptor that was not yet issued to the
hardware.
2/ when in tasklet at atc_advance_work() time, atchan->active_list was
queried without holding the lock of the chan. This can result in
atchan->active_list concurrency problems between the tasklet and
issue_pending().

Fixes: dc78baa2b9 ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-8-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:57 +05:30
Tudor Ambarus
6e5ad28d16 dmaengine: at_hdmac: Protect atchan->status with the channel lock
Now that the complete callback call was removed from
device_terminate_all(), we can protect the atchan->status with the channel
lock. The atomic bitops on atchan->status do not substitute proper locking
on the status, as one could still modify the status after the lock was
dropped in atc_terminate_all() but before the atomic bitops were executed.

Fixes: 078a650614 ("dmaengine: at_hdmac: Fix deadlocks")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-7-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:56 +05:30
Tudor Ambarus
f645f85ae1 dmaengine: at_hdmac: Do not call the complete callback on device_terminate_all
The method was wrong because it violated the dmaengine API. For aborted
transfers the complete callback should not be called. Fix the behavior and
do not call the complete callback on device_terminate_all.

Fixes: 808347f6a3 ("dmaengine: at_hdmac: add DMA slave transfers")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-6-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:56 +05:30
Tudor Ambarus
fcd37565ef dmaengine: at_hdmac: Fix premature completion of desc in issue_pending
Multiple calls to atc_issue_pending() could result in a premature
completion of a descriptor from the atchan->active list, as the method
always completed the first active descriptor from the list. Instead,
issue_pending() should just take the first transaction descriptor from the
pending queue, move it to active_list and start the transfer.

Fixes: dc78baa2b9 ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-5-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:56 +05:30
Tudor Ambarus
8a47221fc2 dmaengine: at_hdmac: Start transfer for cyclic channels in issue_pending
Cyclic channels must too call issue_pending in order to start a transfer.
Start the transfer in issue_pending regardless of the type of channel.
This wrongly worked before, because in the past the transfer was started
at tx_submit level when only a desc in the transfer list.

Fixes: 53830cc759 ("dmaengine: at_hdmac: add cyclic DMA operation support")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-4-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:56 +05:30
Tudor Ambarus
7176a6a898 dmaengine: at_hdmac: Don't start transactions at tx_submit level
tx_submit is supposed to push the current transaction descriptor to a
pending queue, waiting for issue_pending() to be called. issue_pending()
must start the transfer, not tx_submit(), thus remove atc_dostart() from
atc_tx_submit(). Clients of at_xdmac that assume that tx_submit() starts
the transfer must be updated and call dma_async_issue_pending() if they
miss to call it.
The vdbg print was moved to after the lock is released. It is desirable to
do the prints without the lock held if possible, and because the if
statement disappears there's no reason why to do the print while holding
the lock.

Fixes: dc78baa2b9 ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-3-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:56 +05:30
Tudor Ambarus
f1171bbdd2 dmaengine: at_hdmac: Fix at_lli struct definition
Those hardware registers are all of 32 bits, while dma_addr_t ca be of
type u64 or u32 depending on CONFIG_ARCH_DMA_ADDR_T_64BIT. Force u32 to
comply with what the hardware expects.

Fixes: dc78baa2b9 ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller")
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-2-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:56 +05:30
Amelie Delaunay
140fd5e74a dmaengine: stm32-dma: fix potential race between pause and resume
When disabling dma channel, a TCF flag is set and as TCIE is enabled, an
interrupt is raised.
On a busy system, the interrupt may have latency and the user can ask for
dmaengine_resume while stm32-dma driver has not yet managed the complete
pause (backup of registers to restore state in resume).
To avoid such a case, instead of waiting the interrupt to backup the
registers, do it just after disabling the channel and discard Transfer
Complete interrupt in case the channel is paused.

Fixes: 099a9a94be ("dmaengine: stm32-dma: add device_pause/device_resume support")
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/20221024083611.132588-1-amelie.delaunay@foss.st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:56 +05:30
Yang Yingliang
ac2b9f34f0 dmaengine: ti: k3-udma-glue: fix memory leak when register device fail
If device_register() fails, it should call put_device() to give
up reference, the name allocated in dev_set_name() can be freed
in callback function kobject_cleanup().

Fixes: 5b65781d06 ("dmaengine: ti: k3-udma-glue: Add support for K3 PKTDMA")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20221020062827.2914148-1-yangyingliang@huawei.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:56 +05:30
Christophe JAILLET
081195d17a dmaengine: mv_xor_v2: Fix a resource leak in mv_xor_v2_remove()
A clk_prepare_enable() call in the probe is not balanced by a corresponding
clk_disable_unprepare() in the remove function.

Add the missing call.

Fixes: 3cd2c313f1 ("dmaengine: mv_xor_v2: Fix clock resource by adding a register clock")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/e9e3837a680c9bd2438e4db2b83270c6c052d005.1666640987.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:56 +05:30
Martin Povišer
8454f880c2 dmaengine: apple-admac: Fix grabbing of channels in of_xlate
The of_xlate callback is supposed to return the channel after already
having 'grabbed' it for private use, so fill that in.

Fixes: b127315d9a ("dmaengine: apple-admac: Add Apple ADMAC driver")
Signed-off-by: Martin Povišer <povik+lin@cutebit.org>
Link: https://lore.kernel.org/r/20221019132324.8585-1-povik+lin@cutebit.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:56 +05:30
Fengqian Gao
0b8c97a1d8 dmaengine: idxd: fix RO device state error after been disabled/reset
When IDXD is not configurable, that means its WQ, engine, and group
configurations cannot be changed. But it can be disabled and its state
should be set as disabled regardless it's configurable or not.

Fix this by setting device state IDXD_DEV_DISABLED for read-only device
as well in idxd_device_clear_state().

Fixes: cf4ac3fef3 ("dmaengine: idxd: fix lockdep warning on device driver removal")
Signed-off-by: Fengqian Gao <fengqian.gao@intel.com>
Reviewed-by: Xiaochen Shen <xiaochen.shen@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lore.kernel.org/r/20220930032835.2290-1-fengqian.gao@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:56 +05:30
Xiaochen Shen
e8dbd6445d dmaengine: idxd: Fix max batch size for Intel IAA
>From Intel IAA spec [1], Intel IAA does not support batch processing.

Two batch related default values for IAA are incorrect in current code:
(1) The max batch size of device is set during device initialization,
    that indicates batch is supported. It should be always 0 on IAA.
(2) The max batch size of work queue is set to WQ_DEFAULT_MAX_BATCH (32)
    as the default value regardless of Intel DSA or IAA device during
    work queue setup and cleanup. It should be always 0 on IAA.

Fix the issues by setting the max batch size of device and max batch
size of work queue to 0 on IAA device, that means batch is not
supported.

[1]: https://cdrdv2.intel.com/v1/dl/getContent/721858

Fixes: 23084545db ("dmaengine: idxd: set max_xfer and max_batch for RO device")
Fixes: 92452a72eb ("dmaengine: idxd: set defaults for wq configs")
Fixes: bfe1d56091 ("dmaengine: idxd: Init and probe for Intel data accelerators")
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lore.kernel.org/r/20220930201528.18621-2-xiaochen.shen@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:43:55 +05:30
Doug Brown
b3d726cb84 dmaengine: pxa_dma: use platform_get_irq_optional
The first IRQ is required, but IRQs 1 through (nb_phy_chans - 1) are
optional, because on some platforms (e.g. PXA168) there is a single IRQ
shared between all channels.

This change inhibits a flood of "IRQ index # not found" messages at
startup. Tested on a PXA168-based device.

Fixes: 7723f4c5ec ("driver core: platform: Add an error message to platform_get_irq*()")
Signed-off-by: Doug Brown <doug@schmorgal.com>
Link: https://lore.kernel.org/r/20220906000709.52705-1-doug@schmorgal.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-11-08 10:42:51 +05:30
Fenghua Yu
0ec8ce0739 dmaengine: idxd: Do not enable user type Work Queue without Shared Virtual Addressing
When the idxd_user_drv driver is bound to a Work Queue (WQ) device
without IOMMU or with IOMMU Passthrough without Shared Virtual
Addressing (SVA), the application gains direct access to physical
memory via the device by programming physical address to a submitted
descriptor. This allows direct userspace read and write access to
arbitrary physical memory. This is inconsistent with the security
goals of a good kernel API.

Unlike vfio_pci driver, the IDXD char device driver does not provide any
ways to pin user pages and translate the address from user VA to IOVA or
PA without IOMMU SVA. Therefore the application has no way to instruct the
device to perform DMA function. This makes the char device not usable for
normal application usage.

Since user type WQ without SVA cannot be used for normal application usage
and presents the security issue, bind idxd_user_drv driver and enable user
type WQ only when SVA is enabled (i.e. user PASID is enabled).

Fixes: 448c3de8ac ("dmaengine: idxd: create user driver for wq 'device'")
Cc: stable@vger.kernel.org
Suggested-by: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Link: https://lore.kernel.org/r/20221014222541.3912195-1-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-10-19 19:02:10 +05:30
Amelie Delaunay
5a637f83d9 dmaengine: stm32-mdma: memset stm32_mdma_chan_config struct before using it
New bool m2m_hw has been added at the end of stm32_mdma_chan_config struct
to support the STM32 DMA MDMA chaining.

m2m_hw is set true in stm32_mdma_slave_config() if peripheral_size is set,
but m2m_hw is never initialized false.

To ensure this case, and any further new update of the structure, memset it
to 0 before using it.

Fixes: 6968743227 ("dmaengine: stm32-mdma: add support to be triggered by STM32 DMA")
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/20221017131413.202567-1-amelie.delaunay@foss.st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-10-19 19:01:19 +05:30
Jason A. Donenfeld
197173db99 treewide: use get_random_bytes() when possible
The prandom_bytes() function has been a deprecated inline wrapper around
get_random_bytes() for several releases now, and compiles down to the
exact same code. Replace the deprecated wrapper with a direct call to
the real function. This was done as a basic find and replace.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> # powerpc
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-10-11 17:42:58 -06:00
Linus Torvalds
416a2f4f91 dmaengine updates for v6.1-rc1
New Support:
  - AngeloGioacchino Del Regno added support for MT6795 SoC dma controller
  - Christian Marangi updated qcom-adm controller binding to yaml
  - Geert Uytterhoeven added yaml binding for Renesas r8a779g0 dma controller
  - Luca Weiss added support for Qualcomm SM6350 GPI dma controller
 
 Updates:
  - Amelie Delaunay provided STM32 DMA-MDMA chaining support
  - Andy Shevchenko updated hsu driver to use managed resources
  - Dave Jiang & Jerry Snitselaar provided usual round of idxd driver updates
  - Janne Grunau & Martin Povišer updated apple dma driver for iommu and pd
    properties and removed use of devres for irqs
  - Swati Agarwal added device_synchronize support for Xilinx zynqmp driver
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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 Povišer)

   - 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
  ...
2022-10-07 15:56:34 -07:00
Gaosheng Cui
b957df9846 dmaengine: ioat: remove unused declarations in dma.h
ioat_ring_alloc_order and ioat_ring_max_alloc_order have
been removed since commit cd60cd9613 ("dmaengine: IOATDMA:
Removing descriptor ring reshape"), so remove them.

Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20220911091817.3214271-1-cuigaosheng1@huawei.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 22:46:09 +05:30
Vaishnav Achath
e8e2f92b15 dmaengine: ti: k3-udma: Respond TX done if DMA_PREP_INTERRUPT is not requested
If the DMA consumer driver does not expect the callback for TX done, then
we need not perform the channel RT byte counter calculations and estimate
the completion but return complete on first attempt itself.This assumes
that the consumer who did not request DMA_PREP_INTERRUPT has its own
mechanism for understanding TX completion, example: MCSPI EOW interrupt
can be used as TX completion signal for a SPI transaction.

Signed-off-by: Vaishnav Achath <vaishnav.a@ti.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20220914110049.5842-1-vaishnav.a@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 22:46:09 +05:30
Swati Agarwal
f2b816a1df dmaengine: zynqmp_dma: Add device_synchronize support
dmaengine_synchronize implementation is required to synchronize proper
termination of current transfers so that any memory resources are not freed
while still in use.

Implement this callback in the driver so that framework can use the same
(in dmaengine_terminate_sync/ dmaengine_synchronize).

Signed-off-by: Swati Agarwal <swati.agarwal@amd.com>
Link: https://lore.kernel.org/r/20220915090516.5812-1-swati.agarwal@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 22:46:08 +05:30
Manivannan Sadhasivam
a0188eb6e7 dmaengine: dw-edma: Remove runtime PM support
Currently, the dw-edma driver enables the runtime_pm for parent device
(chip->dev) and increments/decrements the refcount during alloc/free
chan resources callbacks.

This leads to a problem when the eDMA driver has been probed, but the
channels were not used. This scenario can happen when the DW PCIe driver
probes eDMA driver successfully, but the PCI EPF driver decides not to
use eDMA channels and use iATU instead for PCI transfers.

In this case, the underlying device would be runtime suspended due to
pm_runtime_enable() in dw_edma_probe() and the PCI EPF driver would have
no knowledge of it.

Ideally, the eDMA driver should not be the one doing the runtime PM of
the parent device. The responsibility should instead belong to the client
drivers like PCI EPF.

So let's remove the runtime PM support from eDMA driver.

Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220910054700.12205-1-manivannan.sadhasivam@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 22:46:08 +05:30
Dave Jiang
7ca68fa3c8 dmaengine: idxd: add configuration for concurrent batch descriptor processing
Add sysfs knob to allow control of the number of batch descriptors that can
be concurrently processed by an engine in the group as a fraction of the
Maximum Work Descriptors in Progress value specfied in ENGCAP register.
This control knob is part of toggle for QoS control.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Co-developed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lore.kernel.org/r/20220917161222.2835172-6-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 22:46:08 +05:30
Dave Jiang
1f2737521a dmaengine: idxd: add configuration for concurrent work descriptor processing
Add sysfs knob to allow 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 ENGCAP register.
This control knob is part of toggle for QoS control.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Co-developed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lore.kernel.org/r/20220917161222.2835172-5-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 22:46:08 +05:30
Dave Jiang
b0325aefd3 dmaengine: idxd: add WQ operation cap restriction support
DSA 2.0 add the capability of configuring DMA ops on a per workqueue basis.
This means that certain ops can be disabled by the system administrator for
certain wq. By default, all ops are available. A bitmap is used to store
the ops due to total op size of 256 bits and it is more convenient to use a
range list to specify which bits are enabled.

One of the usage to support this is for VM migration between different
iteration of devices. The newer ops are disabled in order to allow guest to
migrate to a host that only support older ops. Another usage is to
restrict the WQ to certain operations for QoS of performance.

A sysfs of ops_config attribute is added per wq. It is only usable when the
ops_config bit is set under WQ_CAP register. This means that this attribute
will return -EOPNOTSUPP on DSA 1.x devices. The expected input is a range
list for the bits per operation the WQ supports.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Co-developed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lore.kernel.org/r/20220917161222.2835172-4-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 22:46:08 +05:30
Dave Jiang
a8563a33a5 dmanegine: idxd: reformat opcap output to match bitmap_parse() input
To make input and output consistent and prepping for the per WQ operation
configuration support, change the output of opcap display to match the
input that is expected by bitmap_parse() helper function. The output will
be a bitmap with field width as the number of bits using the %*pb format
specifier for printk() family.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Co-developed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lore.kernel.org/r/20220917161222.2835172-3-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 22:46:08 +05:30
Dave Jiang
22bd0df846 dmaengine: idxd: convert ats_dis to a wq flag
Make wq attributes access consistent. Convert ats_dis to wq flag
WQ_FLAG_ATS_DISABLE.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Co-developed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lore.kernel.org/r/20220917161222.2835172-2-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 22:46:08 +05:30
Dave Jiang
898ec89dbb dmaengine: ioat: stop mod_timer from resurrecting deleted timer in __cleanup()
User reports observing timer event report channel halted but no error
observed in CHANERR register. The driver finished self-test and released
channel resources. Debug shows that __cleanup() can call
mod_timer() after the timer has been deleted and thus resurrect the
timer. While harmless, it causes suprious error message to be emitted.
Use mod_timer_pending() call to prevent deleted timer from being
resurrected.

Fixes: 3372de5813 ("dmaengine: ioatdma: removal of dma_v3.c and relevant ioat3 references")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/166360672197.3851724.17040290563764838369.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 22:46:08 +05:30
Christian Marangi
b9d2140c3b dmaengine: qcom-adm: fix wrong calling convention for prep_slave_sg
The calling convention for pre_slave_sg is to return NULL on error and
provide an error log to the system. Qcom-adm instead provide error
pointer when an error occur. This indirectly cause kernel panic for
example for the nandc driver that checks only if the pointer returned by
device_prep_slave_sg is not NULL. Returning an error pointer makes nandc
think the device_prep_slave_sg function correctly completed and makes
the kernel panics later in the code.

While nandc is the one that makes the kernel crash, it was pointed out
that the real problem is qcom-adm not following calling convention for
that function.

To fix this, drop returning error pointer and return NULL with an error
log.

Fixes: 03de6b2738 ("dmaengine: qcom-adm: stop abusing slave_id config")
Fixes: 5c9f8c2dbd ("dmaengine: qcom: Add ADM driver")
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Cc: stable@vger.kernel.org # v5.11+
Link: https://lore.kernel.org/r/20220916041256.7104-1-ansuelsmth@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 22:46:07 +05:30
Christian Marangi
7c87653083 dmaengine: qcom-adm: fix wrong sizeof config in slave_config
Fix broken slave_config function that uncorrectly compare the
peripheral_size with the size of the config pointer instead of the size
of the config struct. This cause the crci value to be ignored and cause
a kernel panic on any slave that use adm driver.

To fix this, compare to the size of the struct and NOT the size of the
pointer.

Fixes: 03de6b2738 ("dmaengine: qcom-adm: stop abusing slave_id config")
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Cc: stable@vger.kernel.org # v5.17+
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20220915204844.3838-1-ansuelsmth@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 22:46:07 +05:30
Matt Ranostay
693e9c269e dmaengine: ti: k3-psil: add additional TX threads for j721e
Add matching PSI-L threads mapping for transmission DMA channels
on the J721E platform.

Signed-off-by: Matt Ranostay <mranostay@ti.com>
Link: https://lore.kernel.org/r/20220919205931.8397-2-mranostay@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 21:48:09 +05:30
Matt Ranostay
5cfeaf7cc5 dmaengine: ti: k3-psil: add additional TX threads for j7200
Add matching PSI-L threads mapping for transmission DMA channels
on the J7200 platform.

Signed-off-by: Matt Ranostay <mranostay@ti.com>
Link: https://lore.kernel.org/r/20220919205931.8397-3-mranostay@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 21:48:09 +05:30
Martin Povišer
6aed75d7cc dmaengine: apple-admac: Trigger shared reset
If a reset domain is attached to the device, obtain a shared reference
to it and trigger it. Typically on a chip the ADMAC controller will
share a reset domain with the MCA peripheral.

Signed-off-by: Martin Povišer <povik+lin@cutebit.org>
Link: https://lore.kernel.org/r/20220918095845.68860-5-povik+lin@cutebit.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 21:43:25 +05:30
Martin Povišer
072431595a dmaengine: apple-admac: Do not use devres for IRQs
This is in advance of adding support for triggering the reset signal to
the peripheral, since registering the IRQ handler will have to be
sequenced with it.

Signed-off-by: Martin Povišer <povik+lin@cutebit.org>
Link: https://lore.kernel.org/r/20220918095845.68860-4-povik+lin@cutebit.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 21:43:25 +05:30
Jiapeng Chong
0f4c5b29e3 dmaengine: ti: edma: Remove some unused functions
These functions are defined in the edma.c file, but not called elsewhere,
so delete these unused functions.

drivers/dma/ti/edma.c:746:31: warning: unused function 'to_edma_cc'.
drivers/dma/ti/edma.c:420:20: warning: unused function 'edma_param_or'.
drivers/dma/ti/edma.c:414:20: warning: unused function 'edma_param_and'.
drivers/dma/ti/edma.c:402:20: warning: unused function 'edma_param_write'.
drivers/dma/ti/edma.c:373:28: warning: unused function 'edma_shadow0_read'.
drivers/dma/ti/edma.c:396:28: warning: unused function 'edma_param_read'.
drivers/dma/ti/edma.c:355:20: warning: unused function 'edma_or_array'.

Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2152
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20220914101943.83929-1-jiapeng.chong@linux.alibaba.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 21:25:37 +05:30
Gustavo A. R. Silva
45ecf27f30 dmaengine: sh: rcar-dmac: Replace zero-length arrays with DECLARE_FLEX_ARRAY() helper
Zero-length arrays are deprecated and we are moving towards adopting
C99 flexible-array members, instead. So, replace zero-length arrays
declarations in anonymous union with the new DECLARE_FLEX_ARRAY()
helper macro.

This helper allows for flexible-array members in unions.

Link: https://github.com/KSPP/linux/issues/193
Link: https://github.com/KSPP/linux/issues/217
Link: https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/YzIdsJqsR3LH2qEK@work
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 21:14:32 +05:30
Yuan Can
d1083fd043 dmaengine: idxd: Remove unused struct idxd_fault
Since fault processing code has been removed, struct idxd_fault is not used any
more and can be removed as well.

Signed-off-by: Yuan Can <yuancan@huawei.com>
Link: https://lore.kernel.org/r/20220928014747.106808-1-yuancan@huawei.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 13:11:33 +05:30
Jerry Snitselaar
de5819b994 dmaengine: idxd: track enabled workqueues in bitmap
Now that idxd_wq_disable_cleanup() sets the workqueue state to
IDXD_WQ_DISABLED, use a bitmap to track which workqueues have been
enabled. This will then be used to determine which workqueues
should be re-enabled when attempting a software reset to recover
from a device halt state.

Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20220928154856.623545-3-jsnitsel@redhat.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 13:02:38 +05:30
Jerry Snitselaar
8e527aac05 dmaengine: idxd: Set wq state to disabled in idxd_wq_disable_cleanup()
If we are calling idxd_wq_disable_cleanup(), the workqueue should be
in a disabled state. So set the workqueue state to IDXD_WQ_DISABLED so
that the state reflects that. Currently if there is a device failure,
and a software reset is attempted the workqueues will not be
re-enabled due to idxd_wq_enable() seeing that state as already being
IDXD_WQ_ENABLED.

Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20220928154856.623545-2-jsnitsel@redhat.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 13:02:38 +05:30
Shaomin Deng
5c43442fee dmaengine: pl08x: Fix double word
Fix the double word "many" in comments.

Signed-off-by: Shaomin Deng <dengshaomin@cdjrlc.com>
Link: https://lore.kernel.org/r/20220830150708.24507-1-dengshaomin@cdjrlc.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 12:24:16 +05:30
Shaomin Deng
d7873903cc dmaengine: virt-dma: Fix double word in comments
Delete the double word "many" in comments.

Signed-off-by: Shaomin Deng <dengshaomin@cdjrlc.com>
Link: https://lore.kernel.org/r/20220825144545.3528-1-dengshaomin@cdjrlc.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 12:22:27 +05:30
Tuo Cao
c10a7777dd dmaengine: qcom: gpi: move read_lock_bh to read_lock in tasklet
it is unnecessary to call read_lock_bh in a tasklet.

Signed-off-by: Tuo Cao <91tuocao@gmail.com>
Link: https://lore.kernel.org/r/20220814131323.7029-1-91tuocao@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-09-29 12:21:33 +05:30