At any time, a DMA transfer can be suspended to be restarted later before
the end of the DMA transfer.
In order to restart from the point where the transfer was stopped,
DMA_SxNDTR has to be read after disabling the channel by clearing the EN
bit in DMA_SxCR register, to know the number of data items already
collected.
Peripheral and/or memory addresses have to be updated in order to adjust
the address pointers.
SxNDTR register has to be updated with the remaining number of data items
to be transferred (the value read when the channel was disabled).
Then the channel can be re-enabled to resume the transfer from the point
it was suspended.
If the channel was configured in circular or double-buffer mode, the
circular or double-buffer mode must be disabled before re-enabling the
channel to be able to reconfigure SxNDTR register and re-activate circular
or double-buffer mode on next Transfer Complete interrupt where channel
will be disabled by HW. This is due to the fact that on resume, re-writing
SxNDTR register value updates internal HW auto-reload data counter, and
then it truncates all next transfers after a pause/resume sequence.
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/20220505115611.38845-5-amelie.delaunay@foss.st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
stm32_dma_handle_chan_done() is called on Transfer Complete interrupt.
As DMA_SxSCR register is read in interrupt handler, pass the value as
parameter of stm32_dma_handle_chan_done(). Also return directly if
chan->desc is null to remove one ident level.
Then, stm32_dma_configure_next_sg() is doing something only if
Double-Buffer Mode (DBM) is enabled, so, check it is enabled prior calling
stm32_dma_configure_next_sg(), to remove one ident level in
stm32_dma_configure_next_sg().
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/20220505115611.38845-3-amelie.delaunay@foss.st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
chan->next_sg is used to know which transfer will start after the ongoing
one. It is incremented for each new transfer, either on transfer start for
non-cyclic transfers, or on transfer complete interrupt for cyclic
transfers.
For cyclic transfer, when the last item is reached, chan->next_sg must be
reinitialized to the first item.
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/20220505115611.38845-2-amelie.delaunay@foss.st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
One of the two DMA controllers managed by the DMAMUX can be used by the
coprocessor. It is defined in the device tree with dma-masters.
When the two DMA controllers are used by the main CPU,
dma-masters = <&dma1, &dma2>; is specified in the device tree.
When one of the controllers is used by coprocessor (so not managed by
Linux), dma-masters = <&dma1>; is specified in the device tree.
In this case, Linux driver must not reset the DMAMUX, because it could have
been configured by the coprocessor to use the second DMA controller.
count is the number of DMA controllers defined in dma-masters property.
Reset only if resets property is found and valid in device tree, and if
the two DMA controllers are under Linux control.
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/20220504161724.123180-1-amelie.delaunay@foss.st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
drivers/dma/tegra186-gpc-dma.c: In function ‘tegra_dma_probe’:
drivers/dma/tegra186-gpc-dma.c:1364:24: error: ‘struct iommu_fwspec’ has no member named ‘ids’
stream_id = iommu_spec->ids[0] & 0xffff;
^~
Make TEGRA186_GPC_DMA depends on IOMMU_API to fix this.
Fixes: ee17028009 ("dmaengine: tegra: Add tegra gpcdma driver")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20220505093236.15076-1-yuehaibing@huawei.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The clock controller device on r9a06g032 takes all the memory range that
is described as being a system controller. This range contains many
different (unrelated?) registers besides the ones belonging to the clock
controller, that can necessitate to be accessed from other peripherals.
For instance, the dmamux registers are there. The dmamux "device" will
be described as a child node of the clock/system controller node, which
means we need the top device driver (the clock controller driver in this
case) to populate its children manually. In case of error when
populating the children, we do not fail the probe on purpose to keep the
clk driver up and running.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20220427095653.91804-7-miquel.raynal@bootlin.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The Renesas RZN1 DMA IP is based on a DW core, with eg. an additional
dmamux register located in the system control area which can take up to
32 requests (16 per DMA controller). Each DMA channel can be wired to
two different peripherals.
We need two additional information from the 'dmas' property: the channel
(bit in the dmamux register) that must be accessed and the value of the
mux for this channel.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220427095653.91804-6-miquel.raynal@bootlin.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
In zynqmp_dma_alloc/free_chan_resources functions there is a
potential overflow in the below expressions.
dma_alloc_coherent(chan->dev, (2 * chan->desc_size *
ZYNQMP_DMA_NUM_DESCS),
&chan->desc_pool_p, GFP_KERNEL);
dma_free_coherent(chan->dev,(2 * ZYNQMP_DMA_DESC_SIZE(chan) *
ZYNQMP_DMA_NUM_DESCS),
chan->desc_pool_v, chan->desc_pool_p);
The arguments desc_size and ZYNQMP_DMA_NUM_DESCS were 32 bit. Though
this overflow condition is not observed but it is a potential problem
in the case of 32-bit multiplication. Hence fix it by changing the
desc_size data type to size_t.
In addition to coverity fix it also reuse ZYNQMP_DMA_DESC_SIZE macro in
dma_alloc_coherent API argument.
Addresses-Coverity: Event overflow_before_widen.
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/1652166762-18317-2-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Use platform_irq_get() instead platform_get_resource() for IRQ resource
to fix the probe failure. platform_get_resource() fails to fetch the IRQ
resource as it might not be ready at that time.
platform_irq_get() is also the recommended way to get interrupt as it
directly gives the IRQ number and no conversion from resource is
required.
Fixes: ee17028009 ("dmaengine: tegra: Add tegra gpcdma driver")
Reported-by: Jonathan Hunter <jonathanh@nvidia.com>
Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/20220505091440.12981-1-akhilrajeev@nvidia.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
LKP bot reports a new warning:
Warning:
drivers/dma/ptdma/ptdma-dmaengine.c:262:1: warning: no previous prototype for 'pt_tx_status' [-Wmissing-prototypes]
pt_tx_status() should be static, so declare as such.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: d965068259 ("dmaengine: PTDMA: support polled mode")
Link: https://lore.kernel.org/r/20220421052407.745637-1-vkoul@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
