[PATCH 39/48] ARM: PL08x: don't manipulate txd->srcbus or txd->dstbus during LLI fill
Russell King - ARM Linux
linux at arm.linux.org.uk
Mon Jan 3 17:43:15 EST 2011
Don't alter any txd->srcbus or txd->dstbus values while building the
LLI list. This allows us to see the original dma_addr_t values passed
in via the prep_memcpy() method.
Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
---
drivers/dma/amba-pl08x.c | 159 ++++++++++++++++++++++++----------------------
1 files changed, 83 insertions(+), 76 deletions(-)
diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index be7fa17..39970c5 100644
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -481,38 +481,45 @@ static inline u32 pl08x_cctl_bits(u32 cctl, u8 srcwidth, u8 dstwidth,
return retbits;
}
+struct pl08x_lli_build_data {
+ struct pl08x_txd *txd;
+ struct pl08x_driver_data *pl08x;
+ struct pl08x_bus_data srcbus;
+ struct pl08x_bus_data dstbus;
+ size_t remainder;
+};
+
/*
* Autoselect a master bus to use for the transfer
* this prefers the destination bus if both available
* if fixed address on one bus the other will be chosen
*/
-static void pl08x_choose_master_bus(struct pl08x_bus_data *src_bus,
- struct pl08x_bus_data *dst_bus, struct pl08x_bus_data **mbus,
- struct pl08x_bus_data **sbus, u32 cctl)
+static void pl08x_choose_master_bus(struct pl08x_lli_build_data *bd,
+ struct pl08x_bus_data **mbus, struct pl08x_bus_data **sbus, u32 cctl)
{
if (!(cctl & PL080_CONTROL_DST_INCR)) {
- *mbus = src_bus;
- *sbus = dst_bus;
+ *mbus = &bd->srcbus;
+ *sbus = &bd->dstbus;
} else if (!(cctl & PL080_CONTROL_SRC_INCR)) {
- *mbus = dst_bus;
- *sbus = src_bus;
+ *mbus = &bd->dstbus;
+ *sbus = &bd->srcbus;
} else {
- if (dst_bus->buswidth == 4) {
- *mbus = dst_bus;
- *sbus = src_bus;
- } else if (src_bus->buswidth == 4) {
- *mbus = src_bus;
- *sbus = dst_bus;
- } else if (dst_bus->buswidth == 2) {
- *mbus = dst_bus;
- *sbus = src_bus;
- } else if (src_bus->buswidth == 2) {
- *mbus = src_bus;
- *sbus = dst_bus;
+ if (bd->dstbus.buswidth == 4) {
+ *mbus = &bd->dstbus;
+ *sbus = &bd->srcbus;
+ } else if (bd->srcbus.buswidth == 4) {
+ *mbus = &bd->srcbus;
+ *sbus = &bd->dstbus;
+ } else if (bd->dstbus.buswidth == 2) {
+ *mbus = &bd->dstbus;
+ *sbus = &bd->srcbus;
+ } else if (bd->srcbus.buswidth == 2) {
+ *mbus = &bd->srcbus;
+ *sbus = &bd->dstbus;
} else {
- /* src_bus->buswidth == 1 */
- *mbus = dst_bus;
- *sbus = src_bus;
+ /* bd->srcbus.buswidth == 1 */
+ *mbus = &bd->dstbus;
+ *sbus = &bd->srcbus;
}
}
}
@@ -521,29 +528,29 @@ static void pl08x_choose_master_bus(struct pl08x_bus_data *src_bus,
* Fills in one LLI for a certain transfer descriptor
* and advance the counter
*/
-static void pl08x_fill_lli_for_desc(struct pl08x_driver_data *pl08x,
- struct pl08x_txd *txd, int num_llis, int len, u32 cctl, u32 *remainder)
+static void pl08x_fill_lli_for_desc(struct pl08x_lli_build_data *bd,
+ int num_llis, int len, u32 cctl)
{
- struct pl08x_lli *llis_va = txd->llis_va;
- dma_addr_t llis_bus = txd->llis_bus;
+ struct pl08x_lli *llis_va = bd->txd->llis_va;
+ dma_addr_t llis_bus = bd->txd->llis_bus;
BUG_ON(num_llis >= MAX_NUM_TSFR_LLIS);
llis_va[num_llis].cctl = cctl;
- llis_va[num_llis].src = txd->srcbus.addr;
- llis_va[num_llis].dst = txd->dstbus.addr;
+ llis_va[num_llis].src = bd->srcbus.addr;
+ llis_va[num_llis].dst = bd->dstbus.addr;
llis_va[num_llis].lli = llis_bus + (num_llis + 1) * sizeof(struct pl08x_lli);
- if (pl08x->lli_buses & PL08X_AHB2)
+ if (bd->pl08x->lli_buses & PL08X_AHB2)
llis_va[num_llis].lli |= PL080_LLI_LM_AHB2;
if (cctl & PL080_CONTROL_SRC_INCR)
- txd->srcbus.addr += len;
+ bd->srcbus.addr += len;
if (cctl & PL080_CONTROL_DST_INCR)
- txd->dstbus.addr += len;
+ bd->dstbus.addr += len;
- BUG_ON(*remainder < len);
+ BUG_ON(bd->remainder < len);
- *remainder -= len;
+ bd->remainder -= len;
}
/*
@@ -567,7 +574,7 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
struct pl08x_txd *txd)
{
struct pl08x_bus_data *mbus, *sbus;
- size_t remainder;
+ struct pl08x_lli_build_data bd;
int num_llis = 0;
u32 cctl;
size_t max_bytes_per_lli;
@@ -586,38 +593,43 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
/* Get the default CCTL */
cctl = txd->cctl;
+ bd.txd = txd;
+ bd.pl08x = pl08x;
+ bd.srcbus.addr = txd->srcbus.addr;
+ bd.dstbus.addr = txd->dstbus.addr;
+
/* Find maximum width of the source bus */
- txd->srcbus.maxwidth =
+ bd.srcbus.maxwidth =
pl08x_get_bytes_for_cctl((cctl & PL080_CONTROL_SWIDTH_MASK) >>
PL080_CONTROL_SWIDTH_SHIFT);
/* Find maximum width of the destination bus */
- txd->dstbus.maxwidth =
+ bd.dstbus.maxwidth =
pl08x_get_bytes_for_cctl((cctl & PL080_CONTROL_DWIDTH_MASK) >>
PL080_CONTROL_DWIDTH_SHIFT);
/* Set up the bus widths to the maximum */
- txd->srcbus.buswidth = txd->srcbus.maxwidth;
- txd->dstbus.buswidth = txd->dstbus.maxwidth;
+ bd.srcbus.buswidth = bd.srcbus.maxwidth;
+ bd.dstbus.buswidth = bd.dstbus.maxwidth;
dev_vdbg(&pl08x->adev->dev,
"%s source bus is %d bytes wide, dest bus is %d bytes wide\n",
- __func__, txd->srcbus.buswidth, txd->dstbus.buswidth);
+ __func__, bd.srcbus.buswidth, bd.dstbus.buswidth);
/*
* Bytes transferred == tsize * MIN(buswidths), not max(buswidths)
*/
- max_bytes_per_lli = min(txd->srcbus.buswidth, txd->dstbus.buswidth) *
+ max_bytes_per_lli = min(bd.srcbus.buswidth, bd.dstbus.buswidth) *
PL080_CONTROL_TRANSFER_SIZE_MASK;
dev_vdbg(&pl08x->adev->dev,
"%s max bytes per lli = %zu\n",
__func__, max_bytes_per_lli);
/* We need to count this down to zero */
- remainder = txd->len;
+ bd.remainder = txd->len;
dev_vdbg(&pl08x->adev->dev,
"%s remainder = %zu\n",
- __func__, remainder);
+ __func__, bd.remainder);
/*
* Choose bus to align to
@@ -625,22 +637,20 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
* - if fixed address on one bus chooses other
* - modifies cctl to choose an appropriate master
*/
- pl08x_choose_master_bus(&txd->srcbus, &txd->dstbus,
- &mbus, &sbus, cctl);
+ pl08x_choose_master_bus(&bd, &mbus, &sbus, cctl);
if (txd->len < mbus->buswidth) {
/*
* Less than a bus width available
* - send as single bytes
*/
- while (remainder) {
+ while (bd.remainder) {
dev_vdbg(&pl08x->adev->dev,
"%s single byte LLIs for a transfer of "
"less than a bus width (remain 0x%08x)\n",
- __func__, remainder);
+ __func__, bd.remainder);
cctl = pl08x_cctl_bits(cctl, 1, 1, 1);
- pl08x_fill_lli_for_desc(pl08x, txd, num_llis++, 1,
- cctl, &remainder);
+ pl08x_fill_lli_for_desc(&bd, num_llis++, 1, cctl);
total_bytes++;
}
} else {
@@ -652,10 +662,9 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
dev_vdbg(&pl08x->adev->dev,
"%s adjustment lli for less than bus width "
"(remain 0x%08x)\n",
- __func__, remainder);
+ __func__, bd.remainder);
cctl = pl08x_cctl_bits(cctl, 1, 1, 1);
- pl08x_fill_lli_for_desc(pl08x, txd, num_llis++, 1,
- cctl, &remainder);
+ pl08x_fill_lli_for_desc(&bd, num_llis++, 1, cctl);
total_bytes++;
}
@@ -675,14 +684,14 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
* Make largest possible LLIs until less than one bus
* width left
*/
- while (remainder > (mbus->buswidth - 1)) {
+ while (bd.remainder > (mbus->buswidth - 1)) {
size_t lli_len, target_len, tsize, odd_bytes;
/*
* If enough left try to send max possible,
* otherwise try to send the remainder
*/
- target_len = min(remainder, max_bytes_per_lli);
+ target_len = min(bd.remainder, max_bytes_per_lli);
/*
* Set bus lengths for incrementing buses to the
@@ -690,24 +699,24 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
* limiting on the target length calculated above.
*/
if (cctl & PL080_CONTROL_SRC_INCR)
- txd->srcbus.fill_bytes =
- pl08x_pre_boundary(txd->srcbus.addr,
+ bd.srcbus.fill_bytes =
+ pl08x_pre_boundary(bd.srcbus.addr,
target_len);
else
- txd->srcbus.fill_bytes = target_len;
+ bd.srcbus.fill_bytes = target_len;
if (cctl & PL080_CONTROL_DST_INCR)
- txd->dstbus.fill_bytes =
- pl08x_pre_boundary(txd->dstbus.addr,
+ bd.dstbus.fill_bytes =
+ pl08x_pre_boundary(bd.dstbus.addr,
target_len);
else
- txd->dstbus.fill_bytes = target_len;
+ bd.dstbus.fill_bytes = target_len;
/* Find the nearest */
- lli_len = min(txd->srcbus.fill_bytes,
- txd->dstbus.fill_bytes);
+ lli_len = min(bd.srcbus.fill_bytes,
+ bd.dstbus.fill_bytes);
- BUG_ON(lli_len > remainder);
+ BUG_ON(lli_len > bd.remainder);
if (lli_len <= 0) {
dev_err(&pl08x->adev->dev,
@@ -764,15 +773,15 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
}
cctl = pl08x_cctl_bits(cctl,
- txd->srcbus.buswidth,
- txd->dstbus.buswidth,
+ bd.srcbus.buswidth,
+ bd.dstbus.buswidth,
tsize);
dev_vdbg(&pl08x->adev->dev,
"%s fill lli with single lli chunk of size 0x%08zx (remainder 0x%08zx)\n",
- __func__, lli_len, remainder);
- pl08x_fill_lli_for_desc(pl08x, txd, num_llis++,
- lli_len, cctl, &remainder);
+ __func__, lli_len, bd.remainder);
+ pl08x_fill_lli_for_desc(&bd, num_llis++,
+ lli_len, cctl);
total_bytes += lli_len;
}
@@ -784,14 +793,13 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
*/
int j;
for (j = 0; (j < mbus->buswidth)
- && (remainder); j++) {
+ && (bd.remainder); j++) {
cctl = pl08x_cctl_bits(cctl, 1, 1, 1);
dev_vdbg(&pl08x->adev->dev,
"%s align with boundary, single byte (remain 0x%08zx)\n",
- __func__, remainder);
- pl08x_fill_lli_for_desc(pl08x, txd,
- num_llis++, 1, cctl,
- &remainder);
+ __func__, bd.remainder);
+ pl08x_fill_lli_for_desc(&bd,
+ num_llis++, 1, cctl);
total_bytes++;
}
}
@@ -800,13 +808,12 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
/*
* Send any odd bytes
*/
- while (remainder) {
+ while (bd.remainder) {
cctl = pl08x_cctl_bits(cctl, 1, 1, 1);
dev_vdbg(&pl08x->adev->dev,
"%s align with boundary, single odd byte (remain %zu)\n",
- __func__, remainder);
- pl08x_fill_lli_for_desc(pl08x, txd, num_llis++, 1,
- cctl, &remainder);
+ __func__, bd.remainder);
+ pl08x_fill_lli_for_desc(&bd, num_llis++, 1, cctl);
total_bytes++;
}
}
--
1.6.2.5
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