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SubjectRe: [PATCH] dmaengine: ti: omap-dma: Configure LCH_TYPE for OMAP1
On Thu, Nov 22, 2018 at 03:12:36PM +0000, Russell King - ARM Linux wrote:
> Also we can't deal with the omap_set_dma_dest_burst_mode() setting -
> DMAengine always uses a 64 byte burst, but udc wants a smaller burst
> setting. Does this matter?

Looking at OMAP1 docs, it seems it supports only 16 bytes. Then checking
DMAengine code, I don't think these CSDP bit values are not valid
for OMAP1:

CSDP_SRC_BURST_1 = 0 << 7,
CSDP_SRC_BURST_16 = 1 << 7,
CSDP_SRC_BURST_32 = 2 << 7,
CSDP_SRC_BURST_64 = 3 << 7,

From TI SPRU674 document, pages 50-51:

0 single access (no burst)
1 single access (no burst)
2 burst 4
3 reserved (do not use this setting)

So if CSDP_SRC_BURST_64 (3) gets programmed OMAP1, I wonder what is the
end result, no burst or burst 4...

A.

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