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a8135d0d79
The two API function can cover most, if not all current APIs used to
request a channel. With minimal effort dmaengine drivers, platforms and
dmaengine user drivers can be converted to use the two function.
struct dma_chan *dma_request_chan_by_mask(const dma_cap_mask_t *mask);
To request any channel matching with the requested capabilities, can be
used to request channel for memcpy, memset, xor, etc where no hardware
synchronization is needed.
struct dma_chan *dma_request_chan(struct device *dev, const char *name);
To request a slave channel. The dma_request_chan() will try to find the
channel via DT, ACPI or in case if the kernel booted in non DT/ACPI mode
it will use a filter lookup table and retrieves the needed information from
the dma_slave_map provided by the DMA drivers.
This legacy mode needs changes in platform code, in dmaengine drivers and
finally the dmaengine user drivers can be converted:
For each dmaengine driver an array of DMA device, slave and the parameter
for the filter function needs to be added:
static const struct dma_slave_map da830_edma_map[] = {
{ "davinci-mcasp.0", "rx", EDMA_FILTER_PARAM(0, 0) },
{ "davinci-mcasp.0", "tx", EDMA_FILTER_PARAM(0, 1) },
{ "davinci-mcasp.1", "rx", EDMA_FILTER_PARAM(0, 2) },
{ "davinci-mcasp.1", "tx", EDMA_FILTER_PARAM(0, 3) },
{ "davinci-mcasp.2", "rx", EDMA_FILTER_PARAM(0, 4) },
{ "davinci-mcasp.2", "tx", EDMA_FILTER_PARAM(0, 5) },
{ "spi_davinci.0", "rx", EDMA_FILTER_PARAM(0, 14) },
{ "spi_davinci.0", "tx", EDMA_FILTER_PARAM(0, 15) },
{ "da830-mmc.0", "rx", EDMA_FILTER_PARAM(0, 16) },
{ "da830-mmc.0", "tx", EDMA_FILTER_PARAM(0, 17) },
{ "spi_davinci.1", "rx", EDMA_FILTER_PARAM(0, 18) },
{ "spi_davinci.1", "tx", EDMA_FILTER_PARAM(0, 19) },
};
This information is going to be needed by the dmaengine driver, so
modification to the platform_data is needed, and the driver map should be
added to the pdata of the DMA driver:
da8xx_edma0_pdata.slave_map = da830_edma_map;
da8xx_edma0_pdata.slavecnt = ARRAY_SIZE(da830_edma_map);
The DMA driver then needs to configure the needed device -> filter_fn
mapping before it registers with dma_async_device_register() :
ecc->dma_slave.filter_map.map = info->slave_map;
ecc->dma_slave.filter_map.mapcnt = info->slavecnt;
ecc->dma_slave.filter_map.fn = edma_filter_fn;
When neither DT or ACPI lookup is available the dma_request_chan() will
try to match the requester's device name with the filter_map's list of
device names, when a match found it will use the information from the
dma_slave_map to get the channel with the dma_get_channel() internal
function.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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|---|---|---|
| .. | ||
| bestcomm | ||
| dw | ||
| hsu | ||
| ioat | ||
| ipu | ||
| ppc4xx | ||
| sh | ||
| xilinx | ||
| acpi-dma.c | ||
| amba-pl08x.c | ||
| at_hdmac_regs.h | ||
| at_hdmac.c | ||
| at_xdmac.c | ||
| bcm2835-dma.c | ||
| coh901318_lli.c | ||
| coh901318.c | ||
| coh901318.h | ||
| cppi41.c | ||
| dma-axi-dmac.c | ||
| dma-jz4740.c | ||
| dma-jz4780.c | ||
| dmaengine.c | ||
| dmaengine.h | ||
| dmatest.c | ||
| edma.c | ||
| ep93xx_dma.c | ||
| fsl_raid.c | ||
| fsl_raid.h | ||
| fsl-edma.c | ||
| fsldma.c | ||
| fsldma.h | ||
| idma64.c | ||
| idma64.h | ||
| img-mdc-dma.c | ||
| imx-dma.c | ||
| imx-sdma.c | ||
| iop-adma.c | ||
| k3dma.c | ||
| Kconfig | ||
| lpc18xx-dmamux.c | ||
| Makefile | ||
| mic_x100_dma.c | ||
| mic_x100_dma.h | ||
| mmp_pdma.c | ||
| mmp_tdma.c | ||
| moxart-dma.c | ||
| mpc512x_dma.c | ||
| mv_xor.c | ||
| mv_xor.h | ||
| mxs-dma.c | ||
| nbpfaxi.c | ||
| of-dma.c | ||
| omap-dma.c | ||
| pch_dma.c | ||
| pl330.c | ||
| pxa_dma.c | ||
| qcom_bam_dma.c | ||
| s3c24xx-dma.c | ||
| sa11x0-dma.c | ||
| sirf-dma.c | ||
| ste_dma40_ll.c | ||
| ste_dma40_ll.h | ||
| ste_dma40.c | ||
| sun4i-dma.c | ||
| sun6i-dma.c | ||
| tegra20-apb-dma.c | ||
| ti-dma-crossbar.c | ||
| timb_dma.c | ||
| TODO | ||
| txx9dmac.c | ||
| txx9dmac.h | ||
| virt-dma.c | ||
| virt-dma.h | ||
| xgene-dma.c | ||
| zx296702_dma.c | ||