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fa6a940bf1
max_bytes_per_lli = bd.srcbus.buswidth * PL080_CONTROL_TRANSFER_SIZE_MASK;
This is confirmed by ARM support guys.
Below is summary of mail exchange with them:
[Viresh] What is the total data to be transferred in case source and destination
bus widths are different. Suppose, source bus width is 2 bytes and destination
is 4 bytes. Now in order to transfer 80 bytes, what should be value of
TransferSize field in control reg: 40? or 20?.
[David from ARM] The value that is programmed into the TransferSize field should
be the number of <SourceWidth> transfers needed to achieve the required data
transfer.
So, to transfer 80 bytes, with a Source Width of 2, the TransferSize field =
should be programmed with:
Total transfer size
------------------- = 40
<source width>
[Viresh] Will this change if source is 4 bytes and dest is 2?
[David] Yes - the calculation then becomes:
Total transfer size
------------------- =20
<source width>
Also, max_bytes_per_lli must be calculated after fixing src and dest widths not
before that. So move this code to the correct place.
This patch also removes max_bytes_per_lli from earlier print message, as till
that point max_bytes_per_lli is unknown.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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|---|---|---|
| .. | ||
| ioat | ||
| ipu | ||
| ppc4xx | ||
| amba-pl08x.c | ||
| at_hdmac_regs.h | ||
| at_hdmac.c | ||
| coh901318_lli.c | ||
| coh901318_lli.h | ||
| coh901318.c | ||
| dmaengine.c | ||
| dmatest.c | ||
| dw_dmac_regs.h | ||
| dw_dmac.c | ||
| ep93xx_dma.c | ||
| fsldma.c | ||
| fsldma.h | ||
| imx-dma.c | ||
| imx-sdma.c | ||
| intel_mid_dma_regs.h | ||
| intel_mid_dma.c | ||
| iop-adma.c | ||
| iovlock.c | ||
| Kconfig | ||
| Makefile | ||
| mpc512x_dma.c | ||
| mv_xor.c | ||
| mv_xor.h | ||
| mxs-dma.c | ||
| pch_dma.c | ||
| pl330.c | ||
| shdma.c | ||
| shdma.h | ||
| ste_dma40_ll.c | ||
| ste_dma40_ll.h | ||
| ste_dma40.c | ||
| timb_dma.c | ||
| TODO | ||
| txx9dmac.c | ||
| txx9dmac.h | ||