2 files changed, 155 insertions, 0 deletions

diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index eaa7c4c404ca..7ff30b0f44ed 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -307,6 +307,22 @@ static void axi_chan_block_xfer_start(struct axi_dma_chan *chan,
 	       priority << CH_CFG_H_PRIORITY_POS |
 	       DWAXIDMAC_HS_SEL_HW << CH_CFG_H_HS_SEL_DST_POS |
 	       DWAXIDMAC_HS_SEL_HW << CH_CFG_H_HS_SEL_SRC_POS);
+	switch (chan->direction) {
+	case DMA_MEM_TO_DEV:
+		reg |= (chan->config.device_fc ?
+			DWAXIDMAC_TT_FC_MEM_TO_PER_DST :
+			DWAXIDMAC_TT_FC_MEM_TO_PER_DMAC)
+			<< CH_CFG_H_TT_FC_POS;
+		break;
+	case DMA_DEV_TO_MEM:
+		reg |= (chan->config.device_fc ?
+			DWAXIDMAC_TT_FC_PER_TO_MEM_SRC :
+			DWAXIDMAC_TT_FC_PER_TO_MEM_DMAC)
+			<< CH_CFG_H_TT_FC_POS;
+		break;
+	default:
+		break;
+	}
 	axi_chan_iowrite32(chan, CH_CFG_H, reg);
 
 	write_chan_llp(chan, first->hw_desc[0].llp | lms);
@@ -454,6 +470,141 @@ static void set_desc_dest_master(struct axi_dma_hw_desc *hw_desc,
 	hw_desc->lli->ctl_lo = cpu_to_le32(val);
 }
 
+static int dw_axi_dma_set_hw_desc(struct axi_dma_chan *chan,
+				  struct axi_dma_hw_desc *hw_desc,
+				  dma_addr_t mem_addr, size_t len)
+{
+	unsigned int data_width = BIT(chan->chip->dw->hdata->m_data_width);
+	unsigned int reg_width;
+	unsigned int mem_width;
+	dma_addr_t device_addr;
+	size_t axi_block_ts;
+	size_t block_ts;
+	u32 ctllo, ctlhi;
+	u32 burst_len;
+
+	axi_block_ts = chan->chip->dw->hdata->block_size[chan->id];
+
+	mem_width = __ffs(data_width | mem_addr | len);
+	if (mem_width > DWAXIDMAC_TRANS_WIDTH_32)
+		mem_width = DWAXIDMAC_TRANS_WIDTH_32;
+
+	switch (chan->direction) {
+	case DMA_MEM_TO_DEV:
+		reg_width = __ffs(chan->config.dst_addr_width);
+		device_addr = chan->config.dst_addr;
+		ctllo = reg_width << CH_CTL_L_DST_WIDTH_POS |
+			mem_width << CH_CTL_L_SRC_WIDTH_POS |
+			DWAXIDMAC_CH_CTL_L_NOINC << CH_CTL_L_DST_INC_POS |
+			DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_SRC_INC_POS;
+		block_ts = len >> mem_width;
+		break;
+	case DMA_DEV_TO_MEM:
+		reg_width = __ffs(chan->config.src_addr_width);
+		device_addr = chan->config.src_addr;
+		ctllo = reg_width << CH_CTL_L_SRC_WIDTH_POS |
+			mem_width << CH_CTL_L_DST_WIDTH_POS |
+			DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_DST_INC_POS |
+			DWAXIDMAC_CH_CTL_L_NOINC << CH_CTL_L_SRC_INC_POS;
+		block_ts = len >> reg_width;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (block_ts > axi_block_ts)
+		return -EINVAL;
+
+	hw_desc->lli = axi_desc_get(chan, &hw_desc->llp);
+	if (unlikely(!hw_desc->lli))
+		return -ENOMEM;
+
+	ctlhi = CH_CTL_H_LLI_VALID;
+
+	if (chan->chip->dw->hdata->restrict_axi_burst_len) {
+		burst_len = chan->chip->dw->hdata->axi_rw_burst_len;
+		ctlhi |= CH_CTL_H_ARLEN_EN | CH_CTL_H_AWLEN_EN |
+			 burst_len << CH_CTL_H_ARLEN_POS |
+			 burst_len << CH_CTL_H_AWLEN_POS;
+	}
+
+	hw_desc->lli->ctl_hi = cpu_to_le32(ctlhi);
+
+	if (chan->direction == DMA_MEM_TO_DEV) {
+		write_desc_sar(hw_desc, mem_addr);
+		write_desc_dar(hw_desc, device_addr);
+	} else {
+		write_desc_sar(hw_desc, device_addr);
+		write_desc_dar(hw_desc, mem_addr);
+	}
+
+	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;
+	hw_desc->lli->ctl_lo = cpu_to_le32(ctllo);
+
+	set_desc_src_master(hw_desc);
+
+	return 0;
+}
+
+static struct dma_async_tx_descriptor *
+dw_axi_dma_chan_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
+			      unsigned int sg_len,
+			      enum dma_transfer_direction direction,
+			      unsigned long flags, void *context)
+{
+	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
+	struct axi_dma_hw_desc *hw_desc = NULL;
+	struct axi_dma_desc *desc = NULL;
+	struct scatterlist *sg;
+	unsigned int i;
+	u32 mem, len;
+	int status;
+	u64 llp = 0;
+	u8 lms = 0; /* Select AXI0 master for LLI fetching */
+
+	if (unlikely(!is_slave_direction(direction) || !sg_len))
+		return NULL;
+
+	chan->direction = direction;
+
+	desc = axi_desc_alloc(sg_len);
+	if (unlikely(!desc))
+		goto err_desc_get;
+
+	desc->chan = chan;
+
+	for_each_sg(sgl, sg, sg_len, i) {
+		mem = sg_dma_address(sg);
+		len = sg_dma_len(sg);
+		hw_desc = &desc->hw_desc[i];
+
+		status = dw_axi_dma_set_hw_desc(chan, hw_desc, mem, len);
+		if (status < 0)
+			goto err_desc_get;
+	}
+
+	/* Set end-of-link to the last link descriptor of list */
+	set_desc_last(&desc->hw_desc[sg_len - 1]);
+
+	/* Managed transfer list */
+	do {
+		hw_desc = &desc->hw_desc[--sg_len];
+		write_desc_llp(hw_desc, llp | lms);
+		llp = hw_desc->llp;
+	} while (sg_len);
+
+	return vchan_tx_prep(&chan->vc, &desc->vd, flags);
+
+err_desc_get:
+	if (desc)
+		axi_desc_put(desc);
+
+	return NULL;
+}
+
 static struct dma_async_tx_descriptor *
 dma_chan_prep_dma_memcpy(struct dma_chan *dchan, dma_addr_t dst_adr,
 			 dma_addr_t src_adr, size_t len, unsigned long flags)
@@ -938,12 +1089,14 @@ static int dw_probe(struct platform_device *pdev)
 
 	/* Set capabilities */
 	dma_cap_set(DMA_MEMCPY, dw->dma.cap_mask);
+	dma_cap_set(DMA_SLAVE, dw->dma.cap_mask);
 
 	/* DMA capabilities */
 	dw->dma.chancnt = hdata->nr_channels;
 	dw->dma.src_addr_widths = AXI_DMA_BUSWIDTHS;
 	dw->dma.dst_addr_widths = AXI_DMA_BUSWIDTHS;
 	dw->dma.directions = BIT(DMA_MEM_TO_MEM);
+	dw->dma.directions |= BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
 	dw->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
 
 	dw->dma.dev = chip->dev;
@@ -959,6 +1112,7 @@ static int dw_probe(struct platform_device *pdev)
 	dw->dma.device_prep_dma_memcpy = dma_chan_prep_dma_memcpy;
 	dw->dma.device_synchronize = dw_axi_dma_synchronize;
 	dw->dma.device_config = dw_axi_dma_chan_slave_config;
+	dw->dma.device_prep_slave_sg = dw_axi_dma_chan_prep_slave_sg;
 
 	platform_set_drvdata(pdev, chip);
 
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
index a75b921d6b1a..ac49f2e14b0c 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h
@@ -44,6 +44,7 @@ struct axi_dma_chan {
 
 	struct axi_dma_desc		*desc;
 	struct dma_slave_config		config;
+	enum dma_transfer_direction	direction;
 	/* these other elements are all protected by vc.lock */
 	bool				is_paused;
 };