net: sxgbe: add basic framework for Samsung 10Gb ethernet driver

This patch adds support for Samsung 10Gb ethernet driver(sxgbe).

- sxgbe core initialization
- Tx and Rx support
- MDIO support
- ISRs for Tx and Rx
- ifconfig support to driver

Signed-off-by: Siva Reddy Kallam <siva.kallam@samsung.com>
Signed-off-by: Vipul Pandya <vipul.pandya@samsung.com>
Signed-off-by: Girish K S <ks.giri@samsung.com>
Neatening-by: Joe Perches <joe@perches.com>
Signed-off-by: Byungho An <bh74.an@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 372 insertions, 0 deletions

diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_dma.c b/drivers/net/ethernet/samsung/sxgbe/sxgbe_dma.c
new file mode 100644
index 000000000000..59d2d3976277
--- /dev/null
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_dma.c
@@ -0,0 +1,372 @@
+/* 10G controller driver for Samsung SoCs
+ *
+ * Copyright (C) 2013 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * Author: Siva Reddy Kallam <siva.kallam@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/export.h>
+#include <linux/io.h>
+#include <linux/netdevice.h>
+#include <linux/phy.h>
+
+#include "sxgbe_common.h"
+#include "sxgbe_dma.h"
+#include "sxgbe_reg.h"
+#include "sxgbe_desc.h"
+
+/* DMA core initialization */
+static int sxgbe_dma_init(void __iomem *ioaddr, int fix_burst, int burst_map)
+{
+	int retry_count = 10;
+	u32 reg_val;
+
+	/* reset the DMA */
+	writel(SXGBE_DMA_SOFT_RESET, ioaddr + SXGBE_DMA_MODE_REG);
+	while (retry_count--) {
+		if (!(readl(ioaddr + SXGBE_DMA_MODE_REG) &
+		      SXGBE_DMA_SOFT_RESET))
+			break;
+		mdelay(10);
+	}
+
+	if (retry_count < 0)
+		return -EBUSY;
+
+	reg_val = readl(ioaddr + SXGBE_DMA_SYSBUS_MODE_REG);
+
+	/* if fix_burst = 0, Set UNDEF = 1 of DMA_Sys_Mode Register.
+	 * if fix_burst = 1, Set UNDEF = 0 of DMA_Sys_Mode Register.
+	 * burst_map is bitmap for  BLEN[4, 8, 16, 32, 64, 128 and 256].
+	 * Set burst_map irrespective of fix_burst value.
+	 */
+	if (!fix_burst)
+		reg_val |= SXGBE_DMA_AXI_UNDEF_BURST;
+
+	/* write burst len map */
+	reg_val |= (burst_map << SXGBE_DMA_BLENMAP_LSHIFT);
+
+	writel(reg_val,	ioaddr + SXGBE_DMA_SYSBUS_MODE_REG);
+
+	return 0;
+}
+
+static void sxgbe_dma_channel_init(void __iomem *ioaddr, int cha_num,
+				   int fix_burst, int pbl, dma_addr_t dma_tx,
+				   dma_addr_t dma_rx, int t_rsize, int r_rsize)
+{
+	u32 reg_val;
+	dma_addr_t dma_addr;
+
+	reg_val = readl(ioaddr + SXGBE_DMA_CHA_CTL_REG(cha_num));
+	/* set the pbl */
+	if (fix_burst) {
+		reg_val |= SXGBE_DMA_PBL_X8MODE;
+		writel(reg_val, ioaddr + SXGBE_DMA_CHA_CTL_REG(cha_num));
+		/* program the TX pbl */
+		reg_val = readl(ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cha_num));
+		reg_val |= (pbl << SXGBE_DMA_TXPBL_LSHIFT);
+		writel(reg_val, ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cha_num));
+		/* program the RX pbl */
+		reg_val = readl(ioaddr + SXGBE_DMA_CHA_RXCTL_REG(cha_num));
+		reg_val |= (pbl << SXGBE_DMA_RXPBL_LSHIFT);
+		writel(reg_val, ioaddr + SXGBE_DMA_CHA_RXCTL_REG(cha_num));
+	}
+
+	/* program desc registers */
+	writel(upper_32_bits(dma_tx),
+	       ioaddr + SXGBE_DMA_CHA_TXDESC_HADD_REG(cha_num));
+	writel(lower_32_bits(dma_tx),
+	       ioaddr + SXGBE_DMA_CHA_TXDESC_LADD_REG(cha_num));
+
+	writel(upper_32_bits(dma_rx),
+	       ioaddr + SXGBE_DMA_CHA_RXDESC_HADD_REG(cha_num));
+	writel(lower_32_bits(dma_rx),
+	       ioaddr + SXGBE_DMA_CHA_RXDESC_LADD_REG(cha_num));
+
+	/* program tail pointers */
+	/* assumption: upper 32 bits are constant and
+	 * same as TX/RX desc list
+	 */
+	dma_addr = dma_tx + ((t_rsize - 1) * SXGBE_DESC_SIZE_BYTES);
+	writel(lower_32_bits(dma_addr),
+	       ioaddr + SXGBE_DMA_CHA_TXDESC_TAILPTR_REG(cha_num));
+
+	dma_addr = dma_rx + ((r_rsize - 1) * SXGBE_DESC_SIZE_BYTES);
+	writel(lower_32_bits(dma_addr),
+	       ioaddr + SXGBE_DMA_CHA_RXDESC_LADD_REG(cha_num));
+	/* program the ring sizes */
+	writel(t_rsize - 1, ioaddr + SXGBE_DMA_CHA_TXDESC_RINGLEN_REG(cha_num));
+	writel(r_rsize - 1, ioaddr + SXGBE_DMA_CHA_RXDESC_RINGLEN_REG(cha_num));
+
+	/* Enable TX/RX interrupts */
+	writel(SXGBE_DMA_ENA_INT,
+	       ioaddr + SXGBE_DMA_CHA_INT_ENABLE_REG(cha_num));
+}
+
+static void sxgbe_enable_dma_transmission(void __iomem *ioaddr, int cha_num)
+{
+	u32 tx_config;
+
+	tx_config = readl(ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cha_num));
+	tx_config |= SXGBE_TX_START_DMA;
+	writel(tx_config, ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cha_num));
+}
+
+static void sxgbe_enable_dma_irq(void __iomem *ioaddr, int dma_cnum)
+{
+	/* Enable TX/RX interrupts */
+	writel(SXGBE_DMA_ENA_INT,
+	       ioaddr + SXGBE_DMA_CHA_INT_ENABLE_REG(dma_cnum));
+}
+
+static void sxgbe_disable_dma_irq(void __iomem *ioaddr, int dma_cnum)
+{
+	/* Disable TX/RX interrupts */
+	writel(0, ioaddr + SXGBE_DMA_CHA_INT_ENABLE_REG(dma_cnum));
+}
+
+static void sxgbe_dma_start_tx(void __iomem *ioaddr, int tchannels)
+{
+	int cnum;
+	u32 tx_ctl_reg;
+
+	for (cnum = 0; cnum < tchannels; cnum++) {
+		tx_ctl_reg = readl(ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cnum));
+		tx_ctl_reg |= SXGBE_TX_ENABLE;
+		writel(tx_ctl_reg,
+		       ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cnum));
+	}
+}
+
+static void sxgbe_dma_start_tx_queue(void __iomem *ioaddr, int dma_cnum)
+{
+	u32 tx_ctl_reg;
+
+	tx_ctl_reg = readl(ioaddr + SXGBE_DMA_CHA_TXCTL_REG(dma_cnum));
+	tx_ctl_reg |= SXGBE_TX_ENABLE;
+	writel(tx_ctl_reg, ioaddr + SXGBE_DMA_CHA_TXCTL_REG(dma_cnum));
+}
+
+static void sxgbe_dma_stop_tx_queue(void __iomem *ioaddr, int dma_cnum)
+{
+	u32 tx_ctl_reg;
+
+	tx_ctl_reg = readl(ioaddr + SXGBE_DMA_CHA_TXCTL_REG(dma_cnum));
+	tx_ctl_reg &= ~(SXGBE_TX_ENABLE);
+	writel(tx_ctl_reg, ioaddr + SXGBE_DMA_CHA_TXCTL_REG(dma_cnum));
+}
+
+static void sxgbe_dma_stop_tx(void __iomem *ioaddr, int tchannels)
+{
+	int cnum;
+	u32 tx_ctl_reg;
+
+	for (cnum = 0; cnum < tchannels; cnum++) {
+		tx_ctl_reg = readl(ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cnum));
+		tx_ctl_reg &= ~(SXGBE_TX_ENABLE);
+		writel(tx_ctl_reg, ioaddr + SXGBE_DMA_CHA_TXCTL_REG(cnum));
+	}
+}
+
+static void sxgbe_dma_start_rx(void __iomem *ioaddr, int rchannels)
+{
+	int cnum;
+	u32 rx_ctl_reg;
+
+	for (cnum = 0; cnum < rchannels; cnum++) {
+		rx_ctl_reg = readl(ioaddr + SXGBE_DMA_CHA_RXCTL_REG(cnum));
+		rx_ctl_reg |= SXGBE_RX_ENABLE;
+		writel(rx_ctl_reg,
+		       ioaddr + SXGBE_DMA_CHA_RXCTL_REG(cnum));
+	}
+}
+
+static void sxgbe_dma_stop_rx(void __iomem *ioaddr, int rchannels)
+{
+	int cnum;
+	u32 rx_ctl_reg;
+
+	for (cnum = 0; cnum < rchannels; cnum++) {
+		rx_ctl_reg = readl(ioaddr + SXGBE_DMA_CHA_RXCTL_REG(cnum));
+		rx_ctl_reg &= ~(SXGBE_RX_ENABLE);
+		writel(rx_ctl_reg, ioaddr + SXGBE_DMA_CHA_RXCTL_REG(cnum));
+	}
+}
+
+static int sxgbe_tx_dma_int_status(void __iomem *ioaddr, int channel_no,
+				   struct sxgbe_extra_stats *x)
+{
+	u32 int_status = readl(ioaddr + SXGBE_DMA_CHA_STATUS_REG(channel_no));
+	u32 clear_val = 0;
+	u32 ret_val = 0;
+
+	/* TX Normal Interrupt Summary */
+	if (likely(int_status & SXGBE_DMA_INT_STATUS_NIS)) {
+		x->normal_irq_n++;
+		if (int_status & SXGBE_DMA_INT_STATUS_TI) {
+			ret_val |= handle_tx;
+			x->tx_normal_irq_n++;
+			clear_val |= SXGBE_DMA_INT_STATUS_TI;
+		}
+
+		if (int_status & SXGBE_DMA_INT_STATUS_TBU) {
+			x->tx_underflow_irq++;
+			ret_val |= tx_bump_tc;
+			clear_val |= SXGBE_DMA_INT_STATUS_TBU;
+		}
+	} else if (unlikely(int_status & SXGBE_DMA_INT_STATUS_AIS)) {
+		/* TX Abnormal Interrupt Summary */
+		if (int_status & SXGBE_DMA_INT_STATUS_TPS) {
+			ret_val |= tx_hard_error;
+			clear_val |= SXGBE_DMA_INT_STATUS_TPS;
+			x->tx_process_stopped_irq++;
+		}
+
+		if (int_status & SXGBE_DMA_INT_STATUS_FBE) {
+			ret_val |= tx_hard_error;
+			x->fatal_bus_error_irq++;
+
+			/* Assumption: FBE bit is the combination of
+			 * all the bus access erros and cleared when
+			 * the respective error bits cleared
+			 */
+
+			/* check for actual cause */
+			if (int_status & SXGBE_DMA_INT_STATUS_TEB0) {
+				x->tx_read_transfer_err++;
+				clear_val |= SXGBE_DMA_INT_STATUS_TEB0;
+			} else {
+				x->tx_write_transfer_err++;
+			}
+
+			if (int_status & SXGBE_DMA_INT_STATUS_TEB1) {
+				x->tx_desc_access_err++;
+				clear_val |= SXGBE_DMA_INT_STATUS_TEB1;
+			} else {
+				x->tx_buffer_access_err++;
+			}
+
+			if (int_status & SXGBE_DMA_INT_STATUS_TEB2) {
+				x->tx_data_transfer_err++;
+				clear_val |= SXGBE_DMA_INT_STATUS_TEB2;
+			}
+		}
+
+		/* context descriptor error */
+		if (int_status & SXGBE_DMA_INT_STATUS_CTXTERR) {
+			x->tx_ctxt_desc_err++;
+			clear_val |= SXGBE_DMA_INT_STATUS_CTXTERR;
+		}
+	}
+
+	/* clear the served bits */
+	writel(clear_val, ioaddr + SXGBE_DMA_CHA_STATUS_REG(channel_no));
+
+	return ret_val;
+}
+
+static int sxgbe_rx_dma_int_status(void __iomem *ioaddr, int channel_no,
+				   struct sxgbe_extra_stats *x)
+{
+	u32 int_status = readl(ioaddr + SXGBE_DMA_CHA_STATUS_REG(channel_no));
+	u32 clear_val = 0;
+	u32 ret_val = 0;
+
+	/* RX Normal Interrupt Summary */
+	if (likely(int_status & SXGBE_DMA_INT_STATUS_NIS)) {
+		x->normal_irq_n++;
+		if (int_status & SXGBE_DMA_INT_STATUS_RI) {
+			ret_val |= handle_rx;
+			x->rx_normal_irq_n++;
+			clear_val |= SXGBE_DMA_INT_STATUS_RI;
+		}
+	} else if (unlikely(int_status & SXGBE_DMA_INT_STATUS_AIS)) {
+		/* RX Abnormal Interrupt Summary */
+		if (int_status & SXGBE_DMA_INT_STATUS_RBU) {
+			ret_val |= rx_bump_tc;
+			clear_val |= SXGBE_DMA_INT_STATUS_RBU;
+			x->rx_underflow_irq++;
+		}
+
+		if (int_status & SXGBE_DMA_INT_STATUS_RPS) {
+			ret_val |= rx_hard_error;
+			clear_val |= SXGBE_DMA_INT_STATUS_RPS;
+			x->rx_process_stopped_irq++;
+		}
+
+		if (int_status & SXGBE_DMA_INT_STATUS_FBE) {
+			ret_val |= rx_hard_error;
+			x->fatal_bus_error_irq++;
+
+			/* Assumption: FBE bit is the combination of
+			 * all the bus access erros and cleared when
+			 * the respective error bits cleared
+			 */
+
+			/* check for actual cause */
+			if (int_status & SXGBE_DMA_INT_STATUS_REB0) {
+				x->rx_read_transfer_err++;
+				clear_val |= SXGBE_DMA_INT_STATUS_REB0;
+			} else {
+				x->rx_write_transfer_err++;
+			}
+
+			if (int_status & SXGBE_DMA_INT_STATUS_REB1) {
+				x->rx_desc_access_err++;
+				clear_val |= SXGBE_DMA_INT_STATUS_REB1;
+			} else {
+				x->rx_buffer_access_err++;
+			}
+
+			if (int_status & SXGBE_DMA_INT_STATUS_REB2) {
+				x->rx_data_transfer_err++;
+				clear_val |= SXGBE_DMA_INT_STATUS_REB2;
+			}
+		}
+	}
+
+	/* clear the served bits */
+	writel(clear_val, ioaddr + SXGBE_DMA_CHA_STATUS_REG(channel_no));
+
+	return ret_val;
+}
+
+/* Program the HW RX Watchdog */
+static void sxgbe_dma_rx_watchdog(void __iomem *ioaddr, u32 riwt)
+{
+	u32 que_num;
+
+	SXGBE_FOR_EACH_QUEUE(SXGBE_RX_QUEUES, que_num) {
+		writel(riwt,
+		       ioaddr + SXGBE_DMA_CHA_INT_RXWATCHTMR_REG(que_num));
+	}
+}
+
+static const struct sxgbe_dma_ops sxgbe_dma_ops = {
+	.init				= sxgbe_dma_init,
+	.cha_init			= sxgbe_dma_channel_init,
+	.enable_dma_transmission	= sxgbe_enable_dma_transmission,
+	.enable_dma_irq			= sxgbe_enable_dma_irq,
+	.disable_dma_irq		= sxgbe_disable_dma_irq,
+	.start_tx			= sxgbe_dma_start_tx,
+	.start_tx_queue			= sxgbe_dma_start_tx_queue,
+	.stop_tx			= sxgbe_dma_stop_tx,
+	.stop_tx_queue			= sxgbe_dma_stop_tx_queue,
+	.start_rx			= sxgbe_dma_start_rx,
+	.stop_rx			= sxgbe_dma_stop_rx,
+	.tx_dma_int_status		= sxgbe_tx_dma_int_status,
+	.rx_dma_int_status		= sxgbe_rx_dma_int_status,
+	.rx_watchdog			= sxgbe_dma_rx_watchdog,
+};
+
+const struct sxgbe_dma_ops *sxgbe_get_dma_ops(void)
+{
+	return &sxgbe_dma_ops;
+}