[PATCH 8/8] dmaengine/dw_dmac: Add support for DMA_SLAVE_CONFIG
Viresh Kumar
viresh.kumar at st.com
Mon Jan 16 04:50:36 EST 2012
This patch adds support for DMA_SLAVE_CONFIG in dwc DMAC controller.
Signed-off-by: Viresh Kumar <viresh.kumar at st.com>
---
drivers/dma/dw_dmac.c | 78 ++++++++++++++++++++++++++++++++------------
drivers/dma/dw_dmac_regs.h | 3 ++
include/linux/dw_dmac.h | 6 ---
3 files changed, 60 insertions(+), 27 deletions(-)
diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
index c33c06b..6252dce 100644
--- a/drivers/dma/dw_dmac.c
+++ b/drivers/dma/dw_dmac.c
@@ -33,12 +33,14 @@
* which does not support descriptor writeback.
*/
-#define DWC_DEFAULT_CTLLO(private) ({ \
- struct dw_dma_slave *__slave = (private); \
+#define DWC_DEFAULT_CTLLO(chan) ({ \
+ struct dw_dma_slave *__slave = (chan->private); \
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan); \
+ struct dma_slave_config *sconfig = &dwc->dma_sconfig; \
int dms = __slave ? __slave->dst_master : 0; \
int sms = __slave ? __slave->src_master : 1; \
- u8 smsize = __slave ? __slave->src_msize : DW_DMA_MSIZE_16; \
- u8 dmsize = __slave ? __slave->dst_msize : DW_DMA_MSIZE_16; \
+ u8 smsize = __slave ? sconfig->src_maxburst : DW_DMA_MSIZE_16; \
+ u8 dmsize = __slave ? sconfig->dst_maxburst : DW_DMA_MSIZE_16; \
\
(DWC_CTLL_DST_MSIZE(dmsize) \
| DWC_CTLL_SRC_MSIZE(smsize) \
@@ -664,7 +666,7 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
else
src_width = dst_width = 0;
- ctllo = DWC_DEFAULT_CTLLO(chan->private)
+ ctllo = DWC_DEFAULT_CTLLO(chan)
| DWC_CTLL_DST_WIDTH(dst_width)
| DWC_CTLL_SRC_WIDTH(src_width)
| DWC_CTLL_DST_INC
@@ -725,6 +727,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
{
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
struct dw_dma_slave *dws = chan->private;
+ struct dma_slave_config *sconfig = &dwc->dma_sconfig;
struct dw_desc *prev;
struct dw_desc *first;
u32 ctllo;
@@ -739,17 +742,18 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
if (unlikely(!dws || !sg_len))
return NULL;
- reg_width = dws->reg_width;
prev = first = NULL;
switch (direction) {
case DMA_MEM_TO_DEV:
- ctllo = (DWC_DEFAULT_CTLLO(chan->private)
+ reg_width = sconfig->dst_addr_width;
+ reg = sconfig->dst_addr;
+ ctllo = (DWC_DEFAULT_CTLLO(chan)
| DWC_CTLL_DST_WIDTH(reg_width)
| DWC_CTLL_DST_FIX
| DWC_CTLL_SRC_INC
- | DWC_CTLL_FC(dws->fc));
- reg = dws->tx_reg;
+ | DWC_CTLL_FC(sconfig->device_fc));
+
for_each_sg(sgl, sg, sg_len, i) {
struct dw_desc *desc;
u32 len, dlen, mem;
@@ -801,13 +805,14 @@ slave_sg_todev_fill_desc:
}
break;
case DMA_DEV_TO_MEM:
- ctllo = (DWC_DEFAULT_CTLLO(chan->private)
+ reg_width = sconfig->src_addr_width;
+ reg = sconfig->src_addr;
+ ctllo = (DWC_DEFAULT_CTLLO(chan)
| DWC_CTLL_SRC_WIDTH(reg_width)
| DWC_CTLL_DST_INC
| DWC_CTLL_SRC_FIX
- | DWC_CTLL_FC(dws->fc));
+ | DWC_CTLL_FC(sconfig->device_fc));
- reg = dws->rx_reg;
for_each_sg(sgl, sg, sg_len, i) {
struct dw_desc *desc;
u32 len, dlen, mem;
@@ -877,6 +882,29 @@ err_desc_get:
return NULL;
}
+static int
+set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+
+ /* Check if it is chan is configured for slave transfers */
+ if (!chan->private)
+ return -EINVAL;
+
+ memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig));
+
+ /*
+ * Fix sconfig's burst size according to dw_dmac. We need to convert
+ * them as: 1 -> 0, 2 -> 1, 4 -> 2, 8 -> 3, 16 -> 4.
+ *
+ * This can be done by findiding least significant bit set: n & (n - 1)
+ */
+ sconfig->src_maxburst &= sconfig->src_maxburst - 1;
+ sconfig->dst_maxburst &= sconfig->dst_maxburst - 1;
+
+ return 0;
+}
+
static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
unsigned long arg)
{
@@ -926,8 +954,11 @@ static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
/* Flush all pending and queued descriptors */
list_for_each_entry_safe(desc, _desc, &list, desc_node)
dwc_descriptor_complete(dwc, desc, false);
- } else
+ } else if (cmd == DMA_SLAVE_CONFIG) {
+ return set_runtime_config(chan, (struct dma_slave_config *)arg);
+ } else {
return -ENXIO;
+ }
return 0;
}
@@ -1168,11 +1199,11 @@ struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan,
enum dma_transfer_direction direction)
{
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ struct dma_slave_config *sconfig = &dwc->dma_sconfig;
struct dw_cyclic_desc *cdesc;
struct dw_cyclic_desc *retval = NULL;
struct dw_desc *desc;
struct dw_desc *last = NULL;
- struct dw_dma_slave *dws = chan->private;
unsigned long was_cyclic;
unsigned int reg_width;
unsigned int periods;
@@ -1196,7 +1227,12 @@ struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan,
}
retval = ERR_PTR(-EINVAL);
- reg_width = dws->reg_width;
+
+ if (direction == DMA_MEM_TO_DEV)
+ reg_width = sconfig->dst_addr_width;
+ else
+ reg_width = sconfig->src_addr_width;
+
periods = buf_len / period_len;
/* Check for too big/unaligned periods and unaligned DMA buffer. */
@@ -1229,25 +1265,25 @@ struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan,
switch (direction) {
case DMA_MEM_TO_DEV:
- desc->lli.dar = dws->tx_reg;
+ desc->lli.dar = sconfig->dst_addr;
desc->lli.sar = buf_addr + (period_len * i);
- desc->lli.ctllo = (DWC_DEFAULT_CTLLO(chan->private)
+ desc->lli.ctllo = (DWC_DEFAULT_CTLLO(chan)
| DWC_CTLL_DST_WIDTH(reg_width)
| DWC_CTLL_SRC_WIDTH(reg_width)
| DWC_CTLL_DST_FIX
| DWC_CTLL_SRC_INC
- | DWC_CTLL_FC(dws->fc)
+ | DWC_CTLL_FC(sconfig->device_fc)
| DWC_CTLL_INT_EN);
break;
case DMA_DEV_TO_MEM:
desc->lli.dar = buf_addr + (period_len * i);
- desc->lli.sar = dws->rx_reg;
- desc->lli.ctllo = (DWC_DEFAULT_CTLLO(chan->private)
+ desc->lli.sar = sconfig->src_addr;
+ desc->lli.ctllo = (DWC_DEFAULT_CTLLO(chan)
| DWC_CTLL_SRC_WIDTH(reg_width)
| DWC_CTLL_DST_WIDTH(reg_width)
| DWC_CTLL_DST_INC
| DWC_CTLL_SRC_FIX
- | DWC_CTLL_FC(dws->fc)
+ | DWC_CTLL_FC(sconfig->device_fc)
| DWC_CTLL_INT_EN);
break;
default:
diff --git a/drivers/dma/dw_dmac_regs.h b/drivers/dma/dw_dmac_regs.h
index 5eef694..2005d30 100644
--- a/drivers/dma/dw_dmac_regs.h
+++ b/drivers/dma/dw_dmac_regs.h
@@ -153,6 +153,9 @@ struct dw_dma_chan {
struct dw_cyclic_desc *cdesc;
unsigned int descs_allocated;
+
+ /* configuration passed via DMA_SLAVE_CONFIG */
+ struct dma_slave_config dma_sconfig;
};
static inline struct dw_dma_chan_regs __iomem *
diff --git a/include/linux/dw_dmac.h b/include/linux/dw_dmac.h
index f2c64f9..67271d8 100644
--- a/include/linux/dw_dmac.h
+++ b/include/linux/dw_dmac.h
@@ -86,16 +86,10 @@ enum dw_dma_fc {
*/
struct dw_dma_slave {
struct device *dma_dev;
- dma_addr_t tx_reg;
- dma_addr_t rx_reg;
- enum dw_dma_slave_width reg_width;
u32 cfg_hi;
u32 cfg_lo;
u8 src_master;
u8 dst_master;
- u8 src_msize;
- u8 dst_msize;
- u8 fc;
};
/* Platform-configurable bits in CFG_HI */
--
1.7.8.110.g4cb5d
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