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dmaengine: dw-axi-dmac: Support src_maxburst and dst_maxburst

PATCH In review Tan En De 2 participants 3 messages Nov 6, 2023 – Apr 17, 2024

Subsystems (2)
dmaengine Synopsys DesignWare AXI DMAC driver
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Tan En De

author
#0 lore raw

PATCH v3 1/1 dmaengine: dw-axi-dmac: Support src_maxburst and dst_maxburst

Current implementation has hardcoded CHx_CTL.SRC_MSIZE and CHx_CTL.DST_MSIZE with a constant, namely DWAXIDMAC_BURST_TRANS_LEN_4.

However, to support hardware with different source/destination burst transaction length, the aforementioned values shall be configurable based on dma_slave_config set by client driver.

So, this commit is to allow client driver to configure
- CHx_CTL.SRC_MSIZE via dma_slave_config.src_maxburst
- CHx_CTL.DST_MSIZE via dma_slave_config.dst_maxburst

Signed-off-by Tan En De <[email protected]>

---
v2 -> v3:
- Removed the use of dma_slave_config in dma_chan_prep_dma_memcpy.

---
 drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 18 +++++++++++++++---
 drivers/dma/dw-axi-dmac/dw-axi-dmac.h          |  3 ++-
 2 files changed, 17 insertions(+), 4 deletions(-)
drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c +15 -3
index a86a81ff0caa..2a4747917a3e 100644
@@ -656,7 +656,7 @@ static int dw_axi_dma_set_hw_desc(struct axi_dma_chan *chan,
 	size_t axi_block_ts;
 	size_t block_ts;
 	u32 ctllo, ctlhi;
-	u32 burst_len;
+	u32 burst_len, src_burst_trans_len, dst_burst_trans_len;
 
 	axi_block_ts = chan->chip->dw->hdata->block_size[chan->id];
 

@@ -720,8 +720,20 @@ static int dw_axi_dma_set_hw_desc(struct axi_dma_chan *chan,
 
 	hw_desc->lli->block_ts_lo = cpu_to_le32(block_ts - 1);
 
-	ctllo |= DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_DST_MSIZE_POS |
-		 DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_SRC_MSIZE_POS;
+	dst_burst_trans_len = chan->config.dst_maxburst ?
+				__ffs(chan->config.dst_maxburst) - 1 :
+				DWAXIDMAC_BURST_TRANS_LEN_4;
+	if (dst_burst_trans_len > DWAXIDMAC_BURST_TRANS_LEN_MAX)
+		return -EINVAL;
+	ctllo |= dst_burst_trans_len << CH_CTL_L_DST_MSIZE_POS;
+
+	src_burst_trans_len = chan->config.src_maxburst ?
+				__ffs(chan->config.src_maxburst) - 1 :
+				DWAXIDMAC_BURST_TRANS_LEN_4;
+	if (src_burst_trans_len > DWAXIDMAC_BURST_TRANS_LEN_MAX)
+		return -EINVAL;
+	ctllo |= src_burst_trans_len << CH_CTL_L_SRC_MSIZE_POS;
+
 	hw_desc->lli->ctl_lo = cpu_to_le32(ctllo);
 
 	set_desc_src_master(hw_desc);
drivers/dma/dw-axi-dmac/dw-axi-dmac.h +2 -1
index 454904d99654..652e983409ba 100644
@@ -269,7 +269,8 @@ enum {
 	DWAXIDMAC_BURST_TRANS_LEN_128,
 	DWAXIDMAC_BURST_TRANS_LEN_256,
 	DWAXIDMAC_BURST_TRANS_LEN_512,
-	DWAXIDMAC_BURST_TRANS_LEN_1024
+	DWAXIDMAC_BURST_TRANS_LEN_1024,
+	DWAXIDMAC_BURST_TRANS_LEN_MAX  = DWAXIDMAC_BURST_TRANS_LEN_1024
 };
 
 #define CH_CTL_L_DST_WIDTH_POS		11
Signature · 1 line
2.34.1
author
#1 lore raw

Hi, I see this v3 patch has been marked "Changes Requested". Is there any part to be further modified?
Thanks.

maintainer
#2 lore raw
Quoted 2 lines · EnDe Tan

Hi, I see this v3 patch has been marked "Changes Requested". Is there any part to be further modified?

Can you pls rebase this on dmaengine/next and send again

Signature · 1 line
~Vinod