Add non-Virtex5 support for LL TEMAC driver

This patch adds support for using the LL TEMAC Ethernet driver on
non-Virtex 5 platforms by adding support for accessing the Soft DMA
registers as if they were memory mapped instead of solely through the
DCR's (available on the Virtex 5).

The patch also updates the driver so that it runs on the MicroBlaze.
The changes were tested on the PowerPC 440, PowerPC 405, and the
MicroBlaze platforms.

Signed-off-by: John Tyner <jtyner@cs.ucr.edu>
Signed-off-by: John Linn <john.linn@xilinx.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ll_temac_main.c b/drivers/net/ll_temac_main.c
index 6776575..78c9a2e 100644
--- a/drivers/net/ll_temac_main.c
+++ b/drivers/net/ll_temac_main.c
@@ -20,9 +20,6 @@
  *   or rx, so this should be okay.
  *
  * TODO:
- * - Fix driver to work on more than just Virtex5.  Right now the driver
- *   assumes that the locallink DMA registers are accessed via DCR
- *   instructions.
  * - Factor out locallink DMA code into separate driver
  * - Fix multicast assignment.
  * - Fix support for hardware checksumming.
@@ -116,17 +113,86 @@
 	temac_iow(lp, XTE_CTL0_OFFSET, CNTLREG_WRITE_ENABLE_MASK | reg);
 }
 
+/**
+ * temac_dma_in32 - Memory mapped DMA read, this function expects a
+ * register input that is based on DCR word addresses which
+ * are then converted to memory mapped byte addresses
+ */
 static u32 temac_dma_in32(struct temac_local *lp, int reg)
 {
+	return in_be32((u32 *)(lp->sdma_regs + (reg << 2)));
+}
+
+/**
+ * temac_dma_out32 - Memory mapped DMA read, this function expects a
+ * register input that is based on DCR word addresses which
+ * are then converted to memory mapped byte addresses
+ */
+static void temac_dma_out32(struct temac_local *lp, int reg, u32 value)
+{
+	out_be32((u32 *)(lp->sdma_regs + (reg << 2)), value);
+}
+
+/* DMA register access functions can be DCR based or memory mapped.
+ * The PowerPC 440 is DCR based, the PowerPC 405 and MicroBlaze are both
+ * memory mapped.
+ */
+#ifdef CONFIG_PPC_DCR
+
+/**
+ * temac_dma_dcr_in32 - DCR based DMA read
+ */
+static u32 temac_dma_dcr_in(struct temac_local *lp, int reg)
+{
 	return dcr_read(lp->sdma_dcrs, reg);
 }
 
-static void temac_dma_out32(struct temac_local *lp, int reg, u32 value)
+/**
+ * temac_dma_dcr_out32 - DCR based DMA write
+ */
+static void temac_dma_dcr_out(struct temac_local *lp, int reg, u32 value)
 {
 	dcr_write(lp->sdma_dcrs, reg, value);
 }
 
 /**
+ * temac_dcr_setup - If the DMA is DCR based, then setup the address and
+ * I/O  functions
+ */
+static int temac_dcr_setup(struct temac_local *lp, struct of_device *op,
+				struct device_node *np)
+{
+	unsigned int dcrs;
+
+	/* setup the dcr address mapping if it's in the device tree */
+
+	dcrs = dcr_resource_start(np, 0);
+	if (dcrs != 0) {
+		lp->sdma_dcrs = dcr_map(np, dcrs, dcr_resource_len(np, 0));
+		lp->dma_in = temac_dma_dcr_in;
+		lp->dma_out = temac_dma_dcr_out;
+		dev_dbg(&op->dev, "DCR base: %x\n", dcrs);
+		return 0;
+	}
+	/* no DCR in the device tree, indicate a failure */
+	return -1;
+}
+
+#else
+
+/*
+ * temac_dcr_setup - This is a stub for when DCR is not supported,
+ * such as with MicroBlaze
+ */
+static int temac_dcr_setup(struct temac_local *lp, struct of_device *op,
+				struct device_node *np)
+{
+	return -1;
+}
+
+#endif
+
+/**
  * temac_dma_bd_init - Setup buffer descriptor rings
  */
 static int temac_dma_bd_init(struct net_device *ndev)
@@ -156,14 +222,14 @@
 		lp->rx_bd_v[i].next = lp->rx_bd_p +
 				sizeof(*lp->rx_bd_v) * ((i + 1) % RX_BD_NUM);
 
-		skb = alloc_skb(XTE_MAX_JUMBO_FRAME_SIZE
-				+ XTE_ALIGN, GFP_ATOMIC);
+		skb = netdev_alloc_skb_ip_align(ndev,
+						XTE_MAX_JUMBO_FRAME_SIZE);
+
 		if (skb == 0) {
 			dev_err(&ndev->dev, "alloc_skb error %d\n", i);
 			return -1;
 		}
 		lp->rx_skb[i] = skb;
-		skb_reserve(skb,  BUFFER_ALIGN(skb->data));
 		/* returns physical address of skb->data */
 		lp->rx_bd_v[i].phys = dma_map_single(ndev->dev.parent,
 						     skb->data,
@@ -173,23 +239,23 @@
 		lp->rx_bd_v[i].app0 = STS_CTRL_APP0_IRQONEND;
 	}
 
-	temac_dma_out32(lp, TX_CHNL_CTRL, 0x10220400 |
+	lp->dma_out(lp, TX_CHNL_CTRL, 0x10220400 |
 					  CHNL_CTRL_IRQ_EN |
 					  CHNL_CTRL_IRQ_DLY_EN |
 					  CHNL_CTRL_IRQ_COAL_EN);
 	/* 0x10220483 */
 	/* 0x00100483 */
-	temac_dma_out32(lp, RX_CHNL_CTRL, 0xff010000 |
+	lp->dma_out(lp, RX_CHNL_CTRL, 0xff010000 |
 					  CHNL_CTRL_IRQ_EN |
 					  CHNL_CTRL_IRQ_DLY_EN |
 					  CHNL_CTRL_IRQ_COAL_EN |
 					  CHNL_CTRL_IRQ_IOE);
 	/* 0xff010283 */
 
-	temac_dma_out32(lp, RX_CURDESC_PTR,  lp->rx_bd_p);
-	temac_dma_out32(lp, RX_TAILDESC_PTR,
+	lp->dma_out(lp, RX_CURDESC_PTR,  lp->rx_bd_p);
+	lp->dma_out(lp, RX_TAILDESC_PTR,
 		       lp->rx_bd_p + (sizeof(*lp->rx_bd_v) * (RX_BD_NUM - 1)));
-	temac_dma_out32(lp, TX_CURDESC_PTR, lp->tx_bd_p);
+	lp->dma_out(lp, TX_CURDESC_PTR, lp->tx_bd_p);
 
 	return 0;
 }
@@ -427,9 +493,9 @@
 	temac_indirect_out32(lp, XTE_RXC1_OFFSET, val & ~XTE_RXC1_RXEN_MASK);
 
 	/* Reset Local Link (DMA) */
-	temac_dma_out32(lp, DMA_CONTROL_REG, DMA_CONTROL_RST);
+	lp->dma_out(lp, DMA_CONTROL_REG, DMA_CONTROL_RST);
 	timeout = 1000;
-	while (temac_dma_in32(lp, DMA_CONTROL_REG) & DMA_CONTROL_RST) {
+	while (lp->dma_in(lp, DMA_CONTROL_REG) & DMA_CONTROL_RST) {
 		udelay(1);
 		if (--timeout == 0) {
 			dev_err(&ndev->dev,
@@ -437,7 +503,7 @@
 			break;
 		}
 	}
-	temac_dma_out32(lp, DMA_CONTROL_REG, DMA_TAIL_ENABLE);
+	lp->dma_out(lp, DMA_CONTROL_REG, DMA_TAIL_ENABLE);
 
 	temac_dma_bd_init(ndev);
 
@@ -598,7 +664,7 @@
 		lp->tx_bd_tail = 0;
 
 	/* Kick off the transfer */
-	temac_dma_out32(lp, TX_TAILDESC_PTR, tail_p); /* DMA start */
+	lp->dma_out(lp, TX_TAILDESC_PTR, tail_p); /* DMA start */
 
 	return NETDEV_TX_OK;
 }
@@ -638,16 +704,15 @@
 		ndev->stats.rx_packets++;
 		ndev->stats.rx_bytes += length;
 
-		new_skb = alloc_skb(XTE_MAX_JUMBO_FRAME_SIZE + XTE_ALIGN,
-				GFP_ATOMIC);
+		new_skb = netdev_alloc_skb_ip_align(ndev,
+						XTE_MAX_JUMBO_FRAME_SIZE);
+
 		if (new_skb == 0) {
 			dev_err(&ndev->dev, "no memory for new sk_buff\n");
 			spin_unlock_irqrestore(&lp->rx_lock, flags);
 			return;
 		}
 
-		skb_reserve(new_skb, BUFFER_ALIGN(new_skb->data));
-
 		cur_p->app0 = STS_CTRL_APP0_IRQONEND;
 		cur_p->phys = dma_map_single(ndev->dev.parent, new_skb->data,
 					     XTE_MAX_JUMBO_FRAME_SIZE,
@@ -662,7 +727,7 @@
 		cur_p = &lp->rx_bd_v[lp->rx_bd_ci];
 		bdstat = cur_p->app0;
 	}
-	temac_dma_out32(lp, RX_TAILDESC_PTR, tail_p);
+	lp->dma_out(lp, RX_TAILDESC_PTR, tail_p);
 
 	spin_unlock_irqrestore(&lp->rx_lock, flags);
 }
@@ -673,8 +738,8 @@
 	struct temac_local *lp = netdev_priv(ndev);
 	unsigned int status;
 
-	status = temac_dma_in32(lp, TX_IRQ_REG);
-	temac_dma_out32(lp, TX_IRQ_REG, status);
+	status = lp->dma_in(lp, TX_IRQ_REG);
+	lp->dma_out(lp, TX_IRQ_REG, status);
 
 	if (status & (IRQ_COAL | IRQ_DLY))
 		temac_start_xmit_done(lp->ndev);
@@ -691,8 +756,8 @@
 	unsigned int status;
 
 	/* Read and clear the status registers */
-	status = temac_dma_in32(lp, RX_IRQ_REG);
-	temac_dma_out32(lp, RX_IRQ_REG, status);
+	status = lp->dma_in(lp, RX_IRQ_REG);
+	lp->dma_out(lp, RX_IRQ_REG, status);
 
 	if (status & (IRQ_COAL | IRQ_DLY))
 		ll_temac_recv(lp->ndev);
@@ -793,7 +858,7 @@
 	int i, len = 0;
 
 	for (i = 0; i < 0x11; i++)
-		len += sprintf(buf + len, "%.8x%s", temac_dma_in32(lp, i),
+		len += sprintf(buf + len, "%.8x%s", lp->dma_in(lp, i),
 			       (i % 8) == 7 ? "\n" : " ");
 	len += sprintf(buf + len, "\n");
 
@@ -819,7 +884,6 @@
 	struct net_device *ndev;
 	const void *addr;
 	int size, rc = 0;
-	unsigned int dcrs;
 
 	/* Init network device structure */
 	ndev = alloc_etherdev(sizeof(*lp));
@@ -869,13 +933,20 @@
 		goto nodev;
 	}
 
-	dcrs = dcr_resource_start(np, 0);
-	if (dcrs == 0) {
-		dev_err(&op->dev, "could not get DMA register address\n");
-		goto nodev;
+	/* Setup the DMA register accesses, could be DCR or memory mapped */
+	if (temac_dcr_setup(lp, op, np)) {
+
+		/* no DCR in the device tree, try non-DCR */
+		lp->sdma_regs = of_iomap(np, 0);
+		if (lp->sdma_regs) {
+			lp->dma_in = temac_dma_in32;
+			lp->dma_out = temac_dma_out32;
+			dev_dbg(&op->dev, "MEM base: %p\n", lp->sdma_regs);
+		} else {
+			dev_err(&op->dev, "unable to map DMA registers\n");
+			goto nodev;
+		}
 	}
-	lp->sdma_dcrs = dcr_map(np, dcrs, dcr_resource_len(np, 0));
-	dev_dbg(&op->dev, "DCR base: %x\n", dcrs);
 
 	lp->rx_irq = irq_of_parse_and_map(np, 0);
 	lp->tx_irq = irq_of_parse_and_map(np, 1);