linux.git/drivers/dma/sh, branch v4.16

dmaengine: rcar-dmac: fix max_chunk_size for R-Car Gen3

2018-02-27T15:04:38+00:00

According to R-Car Gen3 Rev.0.80 manual, the DMATCR can be set to
16,777,215 as maximum. So, this patch fixes the max_chunk_size for
safety on all of SoCs. Otherwise, a system may hang if the DMATCR
is set to 0 on R-Car Gen3.

Signed-off-by: Yoshihiro Shimoda 
Reviewed-by: Simon Horman 
Signed-off-by: Vinod Koul

Merge tag 'dmaengine-4.16-rc1' of git://git.infradead.org/users/vkoul/slave-dma

2018-01-31T19:52:20+00:00

Pull dmaengine updates from Vinod Koul:
 "This time is smallish update with updates mainly to drivers:

   - updates to xilinx and zynqmp dma controllers

   - update reside calculation for rcar controller

   - more RSTify fixes for documentation

   - add support for race free transfer termination and updating for
     users for that

   - support for new rev of hidma with addition new APIs to get device
     match data in ACPI/OF

   - random updates to bunch of other drivers"

* tag 'dmaengine-4.16-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (47 commits)
  dmaengine: dmatest: fix container_of member in dmatest_callback
  dmaengine: stm32-dmamux: Remove unnecessary platform_get_resource() error check
  dmaengine: sprd: statify 'sprd_dma_prep_dma_memcpy'
  dmaengine: qcom_hidma: simplify DT resource parsing
  dmaengine: xilinx_dma: Free BD consistent memory
  dmaengine: xilinx_dma: Fix warning variable prev set but not used
  dmaengine: xilinx_dma: properly configure the SG mode bit in the driver for cdma
  dmaengine: doc: format struct fields using monospace
  dmaengine: doc: fix bullet list formatting
  dmaengine: ti-dma-crossbar: Fix event mapping for TPCC_EVT_MUX_60_63
  dmaengine: cppi41: Fix channel queues array size check
  dmaengine: imx-sdma: Add MODULE_FIRMWARE
  dmaengine: xilinx_dma: Fix typos
  dmaengine: xilinx_dma: Differentiate probe based on the ip type
  dmaengine: xilinx_dma: fix style issues from checkpatch
  dmaengine: xilinx_dma: Fix kernel doc warnings
  dmaengine: xilinx_dma: Fix race condition in the driver for multiple descriptor scenario
  dmaeninge: xilinx_dma: Fix bug in multiple frame stores scenario in vdma
  dmaengine: xilinx_dma: Check for channel idle state before submitting dma descriptor
  dmaengine: zynqmp_dma: Fix race condition in the probe
  ...

dmaengine: rcar-dmac: Make DMAC reinit during system resume explicit

2018-01-17T11:46:18+00:00

The current (empty) system sleep callbacks rely on the PM core to force
a runtime resume to reinitialize the DMAC registers during system
resume.  Without a reinitialization, e.g. SCIF DMA will hang silently
after a system resume on R-Car Gen3.

Make this explicit by using pm_runtime_force_{suspend,resume}() as the
system sleep callbacks instead.  Use SET_LATE_SYSTEM_SLEEP_PM_OPS() as
DMA engines must be initialized before all DMA slave devices.

Fixes: 17218e0092f8 "PM / genpd: Stop/start devices without pm_runtime_force_suspend/resume()"
Suggested-by: Ulf Hansson 
Signed-off-by: Geert Uytterhoeven 
Reviewed-by: Ulf Hansson 
Acked-by: Vinod Koul 
Signed-off-by: Rafael J. Wysocki

dmaengine: rcar-dmac: use TCRB instead of TCR for residue

2017-11-29T14:12:57+00:00

SYS/RT/Audio DMAC includes independent data buffers for reading
and writing. Therefore, the read transfer counter and write transfer
counter have different values.
TCR indicates read counter, and TCRB indicates write counter.
The relationship is like below.

	        TCR       TCRB
	[SOURCE] -> [DMAC] -> [SINK]

In the MEM_TO_DEV direction, what really matters is how much data has
been written to the device. If the DMA is interrupted between read and
write, then, the data doesn't end up in the destination, so shouldn't
be counted. TCRB is thus the register we should use in this cases.

In the DEV_TO_MEM direction, the situation is more complex. Both the
read and write side are important. What matters from a data consumer
point of view is how much data has been written to memory.
On the other hand, if the transfer is interrupted between read and
write, we'll end up losing data. It can also be important to report.

In the MEM_TO_MEM direction, what matters is of course how much data
has been written to memory from data consumer point of view.
Here, because read and write have independent data buffers, it will
take a while for TCR and TCRB to become equal. Thus we should check
TCRB in this case, too.

Thus, all cases we should check TCRB instead of TCR.

Without this patch, Sound Capture has noise after PulseAudio support
(= 07b7acb51d2 ("ASoC: rsnd: update pointer more accurate")), because
the recorder will use wrong residue counter which indicates transferred
from sound device, but in reality the data was not yet put to memory
and recorder will record it.

However, because DMAC is buffering data until it can be transferable
size, TCRB might not be updated.
For example, if consumer doesn't know how much data can be received,
it requests enough size to DMAC. But in reality, it might receive very
few data. In such case, DMAC just buffered it until transferable size,
and no TCRB updated.

In such case, this buffered data will be transferred if CHCR::DE bit was
cleared, and this is happen if rcar_dmac_chan_halt(). In other word, it
happen when consumer called dmaengine_terminate_all().

Because of this behavior, it need to flush buffered data when it returns
"residue" (= dmaengine_tx_status()).
Otherwise, consumer might calculate wrong things if it called
dmaengine_tx_status() and dmaengine_terminate_all() consecutively.

Signed-off-by: Kuninori Morimoto 
Tested-by: Hiroyuki Yokoyama 
Tested-by: Ryo Kodama 
Tested-by: Geert Uytterhoeven 
Signed-off-by: Vinod Koul

dmaengine: rcar-dmac: ensure CHCR DE bit is actually 0 after clearing

2017-11-29T14:12:57+00:00

DMAC reads data from source device, and buffered it until transferable
size for sink device. Because of this behavior, DMAC is including
buffered data .

Now, CHCR DE bit is controlling DMA transfer enable/disable.

If DE bit was cleared during data transferring, or during buffering,
it will flush buffered data if source device was peripheral device
(The buffered data will be removed if source device was memory).
Because of this behavior, driver should ensure that DE bit is actually
0 after clearing.

This patch adds new rcar_dmac_chcr_de_barrier() and call it after CHCR
register access.

Signed-off-by: Kuninori Morimoto 
Tested-by: Hiroyuki Yokoyama 
Tested-by: Ryo Kodama 
Tested-by: Geert Uytterhoeven 
Signed-off-by: Vinod Koul

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart 
Reviewed-by: Philippe Ombredanne 
Reviewed-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

dmaengine: rcar-dmac: initialize all data before registering IRQ handler

2017-08-25T06:57:07+00:00

Anton Volkov noticed that engine->dev is NULL before
of_dma_controller_register() in probe.
Thus there might be a NULL pointer dereference in
rcar_dmac_chan_start_xfer while accessing chan->chan.device->dev which
is equal to (&dmac->engine)->dev.
On same reason, same and similar things will happen if we didn't
initialize all necessary data before calling register irq function.
To be more safety code, this patch initialize all necessary data
before calling register irq function.

Reported-by: Anton Volkov 
Signed-off-by: Kuninori Morimoto 
Signed-off-by: Vinod Koul

Merge tag 'dmaengine-4.13-rc1' of git://git.infradead.org/users/vkoul/slave-dma

2017-07-08T19:36:50+00:00

Pull dmaengine updates from Vinod Koul:

 - removal of AVR32 support in dw driver as AVR32 is gone

 - new driver for Broadcom stream buffer accelerator (SBA) RAID driver

 - add support for Faraday Technology FTDMAC020 in amba-pl08x driver

 - IOMMU support in pl330 driver

 - updates to bunch of drivers

* tag 'dmaengine-4.13-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (36 commits)
  dmaengine: qcom_hidma: correct API violation for submit
  dmaengine: zynqmp_dma: Remove max len check in zynqmp_dma_prep_memcpy
  dmaengine: tegra-apb: Really fix runtime-pm usage
  dmaengine: fsl_raid: make of_device_ids const.
  dmaengine: qcom_hidma: allow ACPI/DT parameters to be overridden
  dmaengine: fsldma: set BWC, DAHTS and SAHTS values correctly
  dmaengine: Kconfig: Simplify the help text for MXS_DMA
  dmaengine: pl330: Delete unused functions
  dmaengine: Replace WARN_TAINT_ONCE() with pr_warn_once()
  dmaengine: Kconfig: Extend the dependency for MXS_DMA
  dmaengine: mxs: Use %zu for printing a size_t variable
  dmaengine: ste_dma40: Cleanup scatterlist layering violations
  dmaengine: imx-dma: cleanup scatterlist layering violations
  dmaengine: use proper name for the R-Car SoC
  dmaengine: imx-sdma: Fix compilation warning.
  dmaengine: imx-sdma: Handle return value of clk_prepare_enable
  dmaengine: pl330: Add IOMMU support to slave tranfers
  dmaengine: DW DMAC: Handle return value of clk_prepare_enable
  dmaengine: pl08x: use GENMASK() to create bitmasks
  dmaengine: pl08x: Add support for Faraday Technology FTDMAC020
  ...

rcar-dmac: fixup descriptor pointer for descriptor mode

2017-05-30T06:19:28+00:00

In descriptor mode, the descriptor running pointer is not maintained
by the interrupt handler, thus, driver finds the running descriptor
from the descriptor pointer field in the CHCRB register.
But, CHCRB::DPTR indicates *next* descriptor pointer, not current.
Thus, The residue calculation will be missed. This patch fixup it.

Signed-off-by: Kuninori Morimoto 
Signed-off-by: Vinod Koul

dmaengine: rcar-dmac: wait for ISR to finish before freeing resources

2017-05-19T09:25:23+00:00

This fixes a race condition where the channel resources could be freed
before the ISR had finished running resulting in a NULL pointer
reference from the ISR.

[  167.148934] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[  167.157051] pgd = ffff80003c641000
[  167.160449] [00000000] *pgd=000000007c507003, *pud=000000007c4ff003, *pmd=0000000000000000
[  167.168719] Internal error: Oops: 96000046 [#1] PREEMPT SMP
[  167.174289] Modules linked in:
[  167.177348] CPU: 3 PID: 10547 Comm: dma_ioctl Not tainted 4.11.0-rc1-00001-g8d92afddc2f6633a #73
[  167.186131] Hardware name: Renesas Salvator-X board based on r8a7795 (DT)
[  167.192917] task: ffff80003a411a00 task.stack: ffff80003bcd4000
[  167.198850] PC is at rcar_dmac_chan_prep_sg+0xe0/0x400
[  167.203985] LR is at rcar_dmac_chan_prep_sg+0x48/0x400

Based of previous work by:
    Hiroyuki Yokoyama .

Signed-off-by: Niklas Söderlund 
Signed-off-by: Vinod Koul