@@ -601,23 +601,17 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
bd.srcbus.buswidth = bd.srcbus.maxwidth;
bd.dstbus.buswidth = bd.dstbus.maxwidth;
- /*
- * Bytes transferred == tsize * MIN(buswidths), not max(buswidths)
- */
- max_bytes_per_lli = min(bd.srcbus.buswidth, bd.dstbus.buswidth) *
- PL080_CONTROL_TRANSFER_SIZE_MASK;
-
/* We need to count this down to zero */
bd.remainder = txd->len;
pl08x_choose_master_bus(&bd, &mbus, &sbus, cctl);
- dev_vdbg(&pl08x->adev->dev, "src=0x%08x%s/%u dst=0x%08x%s/%u len=%zu llimax=%zu\n",
+ dev_vdbg(&pl08x->adev->dev, "src=0x%08x%s/%u dst=0x%08x%s/%u len=%zu\n",
bd.srcbus.addr, cctl & PL080_CONTROL_SRC_INCR ? "+" : "",
bd.srcbus.buswidth,
bd.dstbus.addr, cctl & PL080_CONTROL_DST_INCR ? "+" : "",
bd.dstbus.buswidth,
- bd.remainder, max_bytes_per_lli);
+ bd.remainder);
dev_vdbg(&pl08x->adev->dev, "mbus=%s sbus=%s\n",
mbus == &bd.srcbus ? "src" : "dst",
sbus == &bd.srcbus ? "src" : "dst");
@@ -657,6 +651,10 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
sbus->buswidth = 1;
}
+ /* Bytes transferred = tsize * src width, not MIN(buswidths) */
+ max_bytes_per_lli = bd.srcbus.buswidth *
+ PL080_CONTROL_TRANSFER_SIZE_MASK;
+
/*
* Make largest possible LLIs until less than one bus
* width left
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> --- drivers/dma/amba-pl08x.c | 14 ++++++-------- 1 files changed, 6 insertions(+), 8 deletions(-)