linux-stable.git/drivers/dma/xilinx, branch linux-6.8.y

dmaengine: xilinx: xdma: Clarify kdoc in XDMA driver

2024-05-30T07:48:45+00:00

[ Upstream commit 7a71c6dc21d5ae83ab27c39a67845d6d23ac271f ]

Clarify the kernel doc of xdma_fill_descs(), especially how big chunks
will be handled.

Signed-off-by: Miquel Raynal 
Signed-off-by: Louis Chauvet 
Link: https://lore.kernel.org/stable/20240327-digigram-xdma-fixes-v1-3-45f4a52c0283%40bootlin.com
Link: https://lore.kernel.org/r/20240327-digigram-xdma-fixes-v1-3-45f4a52c0283@bootlin.com
Signed-off-by: Vinod Koul 
Signed-off-by: Sasha Levin

dma: xilinx_dpdma: Fix locking

2024-05-02T14:35:33+00:00

[ Upstream commit 244296cc3a155199a8b080d19e645d7d49081a38 ]

There are several places where either chan->lock or chan->vchan.lock was
not held. Add appropriate locking. This fixes lockdep warnings like

[   31.077578] ------------[ cut here ]------------
[   31.077831] WARNING: CPU: 2 PID: 40 at drivers/dma/xilinx/xilinx_dpdma.c:834 xilinx_dpdma_chan_queue_transfer+0x274/0x5e0
[   31.077953] Modules linked in:
[   31.078019] CPU: 2 PID: 40 Comm: kworker/u12:1 Not tainted 6.6.20+ #98
[   31.078102] Hardware name: xlnx,zynqmp (DT)
[   31.078169] Workqueue: events_unbound deferred_probe_work_func
[   31.078272] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   31.078377] pc : xilinx_dpdma_chan_queue_transfer+0x274/0x5e0
[   31.078473] lr : xilinx_dpdma_chan_queue_transfer+0x270/0x5e0
[   31.078550] sp : ffffffc083bb2e10
[   31.078590] x29: ffffffc083bb2e10 x28: 0000000000000000 x27: ffffff880165a168
[   31.078754] x26: ffffff880164e920 x25: ffffff880164eab8 x24: ffffff880164d480
[   31.078920] x23: ffffff880165a148 x22: ffffff880164e988 x21: 0000000000000000
[   31.079132] x20: ffffffc082aa3000 x19: ffffff880164e880 x18: 0000000000000000
[   31.079295] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[   31.079453] x14: 0000000000000000 x13: ffffff8802263dc0 x12: 0000000000000001
[   31.079613] x11: 0001ffc083bb2e34 x10: 0001ff880164e98f x9 : 0001ffc082aa3def
[   31.079824] x8 : 0001ffc082aa3dec x7 : 0000000000000000 x6 : 0000000000000516
[   31.079982] x5 : ffffffc7f8d43000 x4 : ffffff88003c9c40 x3 : ffffffffffffffff
[   31.080147] x2 : ffffffc7f8d43000 x1 : 00000000000000c0 x0 : 0000000000000000
[   31.080307] Call trace:
[   31.080340]  xilinx_dpdma_chan_queue_transfer+0x274/0x5e0
[   31.080518]  xilinx_dpdma_issue_pending+0x11c/0x120
[   31.080595]  zynqmp_disp_layer_update+0x180/0x3ac
[   31.080712]  zynqmp_dpsub_plane_atomic_update+0x11c/0x21c
[   31.080825]  drm_atomic_helper_commit_planes+0x20c/0x684
[   31.080951]  drm_atomic_helper_commit_tail+0x5c/0xb0
[   31.081139]  commit_tail+0x234/0x294
[   31.081246]  drm_atomic_helper_commit+0x1f8/0x210
[   31.081363]  drm_atomic_commit+0x100/0x140
[   31.081477]  drm_client_modeset_commit_atomic+0x318/0x384
[   31.081634]  drm_client_modeset_commit_locked+0x8c/0x24c
[   31.081725]  drm_client_modeset_commit+0x34/0x5c
[   31.081812]  __drm_fb_helper_restore_fbdev_mode_unlocked+0x104/0x168
[   31.081899]  drm_fb_helper_set_par+0x50/0x70
[   31.081971]  fbcon_init+0x538/0xc48
[   31.082047]  visual_init+0x16c/0x23c
[   31.082207]  do_bind_con_driver.isra.0+0x2d0/0x634
[   31.082320]  do_take_over_console+0x24c/0x33c
[   31.082429]  do_fbcon_takeover+0xbc/0x1b0
[   31.082503]  fbcon_fb_registered+0x2d0/0x34c
[   31.082663]  register_framebuffer+0x27c/0x38c
[   31.082767]  __drm_fb_helper_initial_config_and_unlock+0x5c0/0x91c
[   31.082939]  drm_fb_helper_initial_config+0x50/0x74
[   31.083012]  drm_fbdev_dma_client_hotplug+0xb8/0x108
[   31.083115]  drm_client_register+0xa0/0xf4
[   31.083195]  drm_fbdev_dma_setup+0xb0/0x1cc
[   31.083293]  zynqmp_dpsub_drm_init+0x45c/0x4e0
[   31.083431]  zynqmp_dpsub_probe+0x444/0x5e0
[   31.083616]  platform_probe+0x8c/0x13c
[   31.083713]  really_probe+0x258/0x59c
[   31.083793]  __driver_probe_device+0xc4/0x224
[   31.083878]  driver_probe_device+0x70/0x1c0
[   31.083961]  __device_attach_driver+0x108/0x1e0
[   31.084052]  bus_for_each_drv+0x9c/0x100
[   31.084125]  __device_attach+0x100/0x298
[   31.084207]  device_initial_probe+0x14/0x20
[   31.084292]  bus_probe_device+0xd8/0xdc
[   31.084368]  deferred_probe_work_func+0x11c/0x180
[   31.084451]  process_one_work+0x3ac/0x988
[   31.084643]  worker_thread+0x398/0x694
[   31.084752]  kthread+0x1bc/0x1c0
[   31.084848]  ret_from_fork+0x10/0x20
[   31.084932] irq event stamp: 64549
[   31.084970] hardirqs last  enabled at (64548): [] _raw_spin_unlock_irqrestore+0x80/0x90
[   31.085157] hardirqs last disabled at (64549): [] _raw_spin_lock_irqsave+0xc0/0xdc
[   31.085277] softirqs last  enabled at (64503): [] __do_softirq+0x47c/0x500
[   31.085390] softirqs last disabled at (64498): [] ____do_softirq+0x10/0x1c
[   31.085501] ---[ end trace 0000000000000000 ]---

Fixes: 7cbb0c63de3f ("dmaengine: xilinx: dpdma: Add the Xilinx DisplayPort DMA engine driver")
Signed-off-by: Sean Anderson 
Reviewed-by: Tomi Valkeinen 
Link: https://lore.kernel.org/r/20240308210034.3634938-2-sean.anderson@linux.dev
Signed-off-by: Vinod Koul 
Signed-off-by: Sasha Levin

dmaengine: xilinx: xdma: Fix synchronization issue

2024-05-02T14:35:29+00:00

commit 6a40fb8245965b481b4dcce011cd63f20bf91ee0 upstream.

The current xdma_synchronize method does not properly wait for the last
transfer to be done. Due to limitations of the XMDA engine, it is not
possible to stop a transfer in the middle of a descriptor. Said
otherwise, if a stop is requested at the end of descriptor "N" and the OS
is fast enough, the DMA controller will effectively stop immediately.
However, if the OS is slightly too slow to request the stop and the DMA
engine starts descriptor "N+1", the N+1 transfer will be performed until
its end. This means that after a terminate_all, the last descriptor must
remain valid and the synchronization must wait for this last descriptor to
be terminated.

Fixes: 855c2e1d1842 ("dmaengine: xilinx: xdma: Rework xdma_terminate_all()")
Fixes: f5c392d106e7 ("dmaengine: xilinx: xdma: Add terminate_all/synchronize callbacks")
Cc: stable@vger.kernel.org
Suggested-by: Miquel Raynal 
Signed-off-by: Louis Chauvet 
Link: https://lore.kernel.org/r/20240327-digigram-xdma-fixes-v1-2-45f4a52c0283@bootlin.com
Signed-off-by: Vinod Koul 
Signed-off-by: Greg Kroah-Hartman

dmaengine: xilinx: xdma: Fix wrong offsets in the buffers addresses in dma descriptor

2024-05-02T14:35:28+00:00

commit 5b9706bfc094314c600ab810a61208a7cbaa4cb3 upstream.

The addition of interleaved transfers slightly changed the way
addresses inside DMA descriptors are derived, breaking cyclic
transfers.

Fixes: 3e184e64c2e5 ("dmaengine: xilinx: xdma: Prepare the introduction of interleaved DMA transfers")
Cc: stable@vger.kernel.org
Signed-off-by: Miquel Raynal 
Signed-off-by: Louis Chauvet 
Link: https://lore.kernel.org/r/20240327-digigram-xdma-fixes-v1-1-45f4a52c0283@bootlin.com
Signed-off-by: Vinod Koul 
Signed-off-by: Greg Kroah-Hartman

dmaengine: xilinx: xdma: Fix kernel-doc warnings

2024-01-19T12:13:40+00:00

Replace hyphens with colons where necessary.

Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202312230634.3AIMQ3OP-lkp@intel.com/
Signed-off-by: Jan Kuliga 
Reviewed-by: Randy Dunlap 
Link: https://lore.kernel.org/r/20231222231728.7156-1-jankul@alatek.krakow.pl
Signed-off-by: Vinod Koul

dmaengine: xilinx: xdma: Fix initialization location of desc in xdma_channel_isr()

2024-01-19T11:34:02+00:00

Clang warns (or errors with CONFIG_WERROR=y):

  drivers/dma/xilinx/xdma.c:894:3: error: variable 'desc' is uninitialized when used here [-Werror,-Wuninitialized]
    894 |                 desc->error = true;
        |                 ^~~~

The initialization of desc was moved too far forward, move it back so
that this assignment does not result in a potential crash at runtime
while clearing up the warning.

Closes: https://github.com/ClangBuiltLinux/linux/issues/1972
Fixes: 2f8f90cd2f8d ("dmaengine: xilinx: xdma: Implement interleaved DMA transfers")
Signed-off-by: Nathan Chancellor 
Link: https://lore.kernel.org/r/20231222-dma-xilinx-xdma-clang-fixes-v1-2-84a18ff184d2@kernel.org
Signed-off-by: Vinod Koul

dmaengine: xilinx: xdma: Fix operator precedence in xdma_prep_interleaved_dma()

2024-01-19T11:34:02+00:00

Clang warns (or errors with CONFIG_WERROR=y):

  drivers/dma/xilinx/xdma.c:757:68: error: operator '?:' has lower precedence than '+'; '+' will be evaluated first [-Werror,-Wparentheses]
    757 |                 src_addr += dmaengine_get_src_icg(xt, &xt->sgl[i]) + xt->src_inc ?
        |                             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^
  drivers/dma/xilinx/xdma.c:757:68: note: place parentheses around the '+' expression to silence this warning
    757 |                 src_addr += dmaengine_get_src_icg(xt, &xt->sgl[i]) + xt->src_inc ?
        |                                                                                  ^
        |                             (                                                   )
  drivers/dma/xilinx/xdma.c:757:68: note: place parentheses around the '?:' expression to evaluate it first
    757 |                 src_addr += dmaengine_get_src_icg(xt, &xt->sgl[i]) + xt->src_inc ?
        |                                                                                  ^
        |                                                                      (
    758 |                                                               xt->sgl[i].size : 0;
        |
        |                                                                                  )
  drivers/dma/xilinx/xdma.c:759:68: error: operator '?:' has lower precedence than '+'; '+' will be evaluated first [-Werror,-Wparentheses]
    759 |                 dst_addr += dmaengine_get_dst_icg(xt, &xt->sgl[i]) + xt->dst_inc ?
        |                             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^
  drivers/dma/xilinx/xdma.c:759:68: note: place parentheses around the '+' expression to silence this warning
    759 |                 dst_addr += dmaengine_get_dst_icg(xt, &xt->sgl[i]) + xt->dst_inc ?
        |                                                                                  ^
        |                             (                                                   )
  drivers/dma/xilinx/xdma.c:759:68: note: place parentheses around the '?:' expression to evaluate it first
    759 |                 dst_addr += dmaengine_get_dst_icg(xt, &xt->sgl[i]) + xt->dst_inc ?
        |                                                                                  ^
        |                                                                      (
    760 |                                                               xt->sgl[i].size : 0;
        |
        |                                                                                  )

The src_inc and dst_inc members of 'struct dma_interleaved_template' are
booleans, so it does not make sense for the addition to happen first.
Wrap the conditional operator in parantheses so it is evaluated first.

Closes: https://github.com/ClangBuiltLinux/linux/issues/1971
Fixes: 2f8f90cd2f8d ("dmaengine: xilinx: xdma: Implement interleaved DMA transfers")
Signed-off-by: Nathan Chancellor 
Link: https://lore.kernel.org/r/20231222-dma-xilinx-xdma-clang-fixes-v1-1-84a18ff184d2@kernel.org
Signed-off-by: Vinod Koul

dmaengine: xilinx: xdma: statify xdma_prep_interleaved_dma

2023-12-22T15:47:52+00:00

xdma_prep_interleaved_dma() was local to file but not declared static,
leading to warning:

drivers/dma/xilinx/xdma.c:729:1: warning: no previous prototype for 'xdma_prep_interleaved_dma' [-Wmissing-prototypes]
  729 | xdma_prep_interleaved_dma(struct dma_chan *chan

Reported-by: Stephen Rothwell 
Signed-off-by: Vinod Koul 
Link: https://lore.kernel.org/r/20231222094001.731889-1-vkoul@kernel.org
Signed-off-by: Vinod Koul

dmaengine: xilinx: xdma: Workaround truncation compilation error

2023-12-22T15:47:52+00:00

Increase length to be copied to be large enough to overcome the
following compilation error. The buf is large enough for this purpose.

drivers/dma/xilinx/xilinx_dpdma.c: In function ‘xilinx_dpdma_debugfs_desc_done_irq_read’:
drivers/dma/xilinx/xilinx_dpdma.c:313:39: error: ‘snprintf’ output may be truncated before the last format character [-Werror=format-truncation=]
  313 |         snprintf(buf, out_str_len, "%d",
      |                                       ^
drivers/dma/xilinx/xilinx_dpdma.c:313:9: note: ‘snprintf’ output between 2 and 6 bytes into a destination of size 5
  313 |         snprintf(buf, out_str_len, "%d",
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  314 |                  dpdma_debugfs.xilinx_dpdma_irq_done_count);
      |                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Vinod Koul 
Link: https://lore.kernel.org/r/20231222094017.731917-1-vkoul@kernel.org
Signed-off-by: Vinod Koul

dmaengine: xilinx: xdma: Implement interleaved DMA transfers

2023-12-22T06:49:41+00:00

Interleaved DMA functionality allows dmaengine clients' to express
DMA transfers in an arbitrary way. This is extremely useful in FPGA
environments, where a greater transfer flexibility is needed. For
instance, in one FPGA design there may be need to do DMA to/from a FIFO
at a fixed address, and also to do DMA to/from a (non)contiguous RAM
memory.

Introduce separate tx preparation callback and add tx-flags handling
logic. Their behavior is based on the description of interleaved DMA
transfers in both source code and the DMAEngine's documentation.

Since XDMA is a fully-fledged scatter-gather dma engine, the logic of
xdma_prep_interleaved_dma() is fairly simple and similar to the other
tx preparation callbacks. The whole tx-flags handling logic resides in
xdma_channel_isr(). Transfer of a single frame from a interleaved DMA
transfer template is pretty similar to the single sg transaction.
Therefore, the transaction of the whole interleaved DMA transfer
template is basically a cyclic dma transaction with finite cycles/periods
(equal to the frame of count) of a single sg transfers.

Signed-off-by: Jan Kuliga 
Link: https://lore.kernel.org/r/20231218113943.9099-9-jankul@alatek.krakow.pl
Signed-off-by: Vinod Koul