net: altera_tse: add mSG-DMA support

The Modular Scatter-Gather DMA core is a new DMA core to work
with the Altera Triple-Speed Ethernet MegaCore. It replaces the
legacy Scatter-Gather Direct Memory Access (SG-DMA) controller
core. Please find details on the "Embedded Peripherals IP User
Guide" of Altera.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Reviewed-by: Marek Vasut <marex@denx.de>

drivers/net/altera_tse.c

@@ -263,6 +263,121 @@ static void altera_tse_stop_sgdma(struct udevice *dev)
 		       &tx_sgdma->control);
 }
 
+static void msgdma_reset(struct msgdma_csr *csr)
+{
+	u32 status;
+	ulong ctime;
+
+	/* Reset mSGDMA */
+	writel(MSGDMA_CSR_STAT_MASK, &csr->status);
+	writel(MSGDMA_CSR_CTL_RESET, &csr->control);
+	ctime = get_timer(0);
+	while (1) {
+		status = readl(&csr->status);
+		if (!(status & MSGDMA_CSR_STAT_RESETTING))
+			break;
+		if (get_timer(ctime) > ALT_TSE_SW_RESET_TIMEOUT) {
+			debug("Reset msgdma timeout\n");
+			break;
+		}
+	}
+	/* Clear status */
+	writel(MSGDMA_CSR_STAT_MASK, &csr->status);
+}
+
+static u32 msgdma_wait(struct msgdma_csr *csr)
+{
+	u32 status;
+	ulong ctime;
+
+	/* Wait for the descriptor to complete */
+	ctime = get_timer(0);
+	while (1) {
+		status = readl(&csr->status);
+		if (!(status & MSGDMA_CSR_STAT_BUSY))
+			break;
+		if (get_timer(ctime) > ALT_TSE_SGDMA_BUSY_TIMEOUT) {
+			debug("sgdma timeout\n");
+			break;
+		}
+	}
+	/* Clear status */
+	writel(MSGDMA_CSR_STAT_MASK, &csr->status);
+
+	return status;
+}
+
+static int altera_tse_send_msgdma(struct udevice *dev, void *packet,
+				  int length)
+{
+	struct altera_tse_priv *priv = dev_get_priv(dev);
+	struct msgdma_extended_desc *desc = priv->tx_desc;
+	u32 tx_buf = virt_to_phys(packet);
+	u32 status;
+
+	writel(tx_buf, &desc->read_addr_lo);
+	writel(0, &desc->read_addr_hi);
+	writel(0, &desc->write_addr_lo);
+	writel(0, &desc->write_addr_hi);
+	writel(length, &desc->len);
+	writel(0, &desc->burst_seq_num);
+	writel(MSGDMA_DESC_TX_STRIDE, &desc->stride);
+	writel(MSGDMA_DESC_CTL_TX_SINGLE, &desc->control);
+	status = msgdma_wait(priv->sgdma_tx);
+	debug("sent %d bytes, status %08x\n", length, status);
+
+	return 0;
+}
+
+static int altera_tse_recv_msgdma(struct udevice *dev, int flags,
+				  uchar **packetp)
+{
+	struct altera_tse_priv *priv = dev_get_priv(dev);
+	struct msgdma_csr *csr = priv->sgdma_rx;
+	struct msgdma_response *resp = priv->rx_resp;
+	u32 level, length, status;
+
+	level = readl(&csr->resp_fill_level);
+	if (level & 0xffff) {
+		length = readl(&resp->bytes_transferred);
+		status = readl(&resp->status);
+		debug("recv %d bytes, status %08x\n", length, status);
+		*packetp = priv->rx_buf;
+
+		return length;
+	}
+
+	return -EAGAIN;
+}
+
+static int altera_tse_free_pkt_msgdma(struct udevice *dev, uchar *packet,
+				      int length)
+{
+	struct altera_tse_priv *priv = dev_get_priv(dev);
+	struct msgdma_extended_desc *desc = priv->rx_desc;
+	u32 rx_buf = virt_to_phys(priv->rx_buf);
+
+	writel(0, &desc->read_addr_lo);
+	writel(0, &desc->read_addr_hi);
+	writel(rx_buf, &desc->write_addr_lo);
+	writel(0, &desc->write_addr_hi);
+	writel(PKTSIZE_ALIGN, &desc->len);
+	writel(0, &desc->burst_seq_num);
+	writel(MSGDMA_DESC_RX_STRIDE, &desc->stride);
+	writel(MSGDMA_DESC_CTL_RX_SINGLE, &desc->control);
+	debug("recv setup\n");
+
+	return 0;
+}
+
+static void altera_tse_stop_msgdma(struct udevice *dev)
+{
+	struct altera_tse_priv *priv = dev_get_priv(dev);
+
+	msgdma_reset(priv->sgdma_rx);
+	msgdma_reset(priv->sgdma_tx);
+}
+
 static int tse_mdio_read(struct mii_dev *bus, int addr, int devad, int reg)
 {
 	struct altera_tse_priv *priv = bus->priv;
@@ -449,6 +564,13 @@ static const struct tse_ops tse_sgdma_ops = {
 	.stop		= altera_tse_stop_sgdma,
 };
 
+static const struct tse_ops tse_msgdma_ops = {
+	.send		= altera_tse_send_msgdma,
+	.recv		= altera_tse_recv_msgdma,
+	.free_pkt	= altera_tse_free_pkt_msgdma,
+	.stop		= altera_tse_stop_msgdma,
+};
+
 static int altera_tse_probe(struct udevice *dev)
 {
 	struct eth_pdata *pdata = dev_get_platdata(dev);
@@ -466,6 +588,8 @@ static int altera_tse_probe(struct udevice *dev)
 	priv->dma_type = dev_get_driver_data(dev);
 	if (priv->dma_type == ALT_SGDMA)
 		priv->ops = &tse_sgdma_ops;
+	else
+		priv->ops = &tse_msgdma_ops;
 	/*
 	 * decode regs. there are multiple reg tuples, and they need to
 	 * match with reg-names.
@@ -490,8 +614,14 @@ static int altera_tse_probe(struct udevice *dev)
 			priv->mac_dev = base;
 		else if (strcmp(list, "rx_csr") == 0)
 			priv->sgdma_rx = base;
+		else if (strcmp(list, "rx_desc") == 0)
+			priv->rx_desc = base;
+		else if (strcmp(list, "rx_resp") == 0)
+			priv->rx_resp = base;
 		else if (strcmp(list, "tx_csr") == 0)
 			priv->sgdma_tx = base;
+		else if (strcmp(list, "tx_desc") == 0)
+			priv->tx_desc = base;
 		else if (strcmp(list, "s1") == 0)
 			desc_mem = base;
 		idx += addrc + sizec;
@@ -567,6 +697,7 @@ static const struct eth_ops altera_tse_ops = {
 };
 
 static const struct udevice_id altera_tse_ids[] = {
+	{ .compatible = "altr,tse-msgdma-1.0", .data = ALT_MSGDMA },
 	{ .compatible = "altr,tse-1.0", .data = ALT_SGDMA },
 	{}
 };

drivers/net/altera_tse.h

@@ -15,6 +15,7 @@
 
 /* dma type */
 #define ALT_SGDMA	0
+#define ALT_MSGDMA	1
 
 /* SGDMA Stuff */
 #define ALT_SGDMA_STATUS_BUSY_MSK				BIT(4)
@@ -87,6 +88,64 @@ struct alt_sgdma_registers {
 	u32 descriptor_pad[3];
 };
 
+/* mSGDMA Stuff */
+
+/* mSGDMA extended descriptor format */
+struct msgdma_extended_desc {
+	u32 read_addr_lo;	/* data buffer source address low bits */
+	u32 write_addr_lo;	/* data buffer destination address low bits */
+	u32 len;
+	u32 burst_seq_num;
+	u32 stride;
+	u32 read_addr_hi;	/* data buffer source address high bits */
+	u32 write_addr_hi;	/* data buffer destination address high bits */
+	u32 control;		/* characteristics of the transfer */
+};
+
+/* mSGDMA descriptor control field bit definitions */
+#define MSGDMA_DESC_CTL_GEN_SOP		BIT(8)
+#define MSGDMA_DESC_CTL_GEN_EOP		BIT(9)
+#define MSGDMA_DESC_CTL_END_ON_EOP	BIT(12)
+#define MSGDMA_DESC_CTL_END_ON_LEN	BIT(13)
+#define MSGDMA_DESC_CTL_GO		BIT(31)
+
+/* Tx buffer control flags */
+#define MSGDMA_DESC_CTL_TX_SINGLE	(MSGDMA_DESC_CTL_GEN_SOP |	\
+					 MSGDMA_DESC_CTL_GEN_EOP |	\
+					 MSGDMA_DESC_CTL_GO)
+
+#define MSGDMA_DESC_CTL_RX_SINGLE	(MSGDMA_DESC_CTL_END_ON_EOP |	\
+					 MSGDMA_DESC_CTL_END_ON_LEN |	\
+					 MSGDMA_DESC_CTL_GO)
+
+/* mSGDMA extended descriptor stride definitions */
+#define MSGDMA_DESC_TX_STRIDE		0x00010001
+#define MSGDMA_DESC_RX_STRIDE		0x00010001
+
+/* mSGDMA dispatcher control and status register map */
+struct msgdma_csr {
+	u32 status;		/* Read/Clear */
+	u32 control;		/* Read/Write */
+	u32 rw_fill_level;
+	u32 resp_fill_level;	/* bit 15:0 */
+	u32 rw_seq_num;
+	u32 pad[3];		/* reserved */
+};
+
+/* mSGDMA CSR status register bit definitions */
+#define MSGDMA_CSR_STAT_BUSY			BIT(0)
+#define MSGDMA_CSR_STAT_RESETTING		BIT(6)
+#define MSGDMA_CSR_STAT_MASK			0x3FF
+
+/* mSGDMA CSR control register bit definitions */
+#define MSGDMA_CSR_CTL_RESET			BIT(1)
+
+/* mSGDMA response register map */
+struct msgdma_response {
+	u32 bytes_transferred;
+	u32 status;
+};
+
 /* TSE Stuff */
 #define ALTERA_TSE_CMD_TX_ENA_MSK		BIT(0)
 #define ALTERA_TSE_CMD_RX_ENA_MSK		BIT(1)
@@ -159,6 +218,7 @@ struct altera_tse_priv {
 	unsigned int tx_fifo_depth;
 	void *rx_desc;
 	void *tx_desc;
+	void *rx_resp;
 	unsigned char *rx_buf;
 	unsigned int phyaddr;
 	unsigned int interface;