Blackfin: on-chip ethernet MAC controller driver

Hi folks,

Here is the blackfin on-chip ethernet MAC controller driver for Linux.

It's name is blackfin-driver-net-stamp537.patch

[PATCH] Blackfin: on-chip ethernet MAC controller driver

This patch implements the driver necessary use the Analog Devices Blackfin processor's on-chip ethernet MAC controller.

...

drivers/net/bfin_mac.c new file +19 -0

+static int bf537mac_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct bf537mac_local *lp = netdev_priv(dev);
+	unsigned int data;
+
+	current_tx_ptr->skb = skb;
+	// Is skb->data always 16-bit aligned? Do we need to memcpy((char *)(tail->packet + 2),skb->data,len)?
+	if ((((unsigned int)(skb->data)) & 0x02) == 2) {
+		//move skb->data to current_tx_ptr payload
+		data = (unsigned int)(skb->data) - 2;
+		*((unsigned short *)data) = (unsigned short)(skb->len);
+		current_tx_ptr->desc_a.start_addr = (unsigned long)data;
+		blackfin_dcache_flush_range(data, (data + (skb->len)) + 2);	//this is important!
+
+	} else {
+		*((unsigned short *)(current_tx_ptr->packet)) =
+		    (unsigned short)(skb->len);
+		memcpy((char *)(current_tx_ptr->packet + 2), skb->data,
+		       (skb->len));

drivers/net/bfin_mac.c new file +19 -0

+	current_tx_ptr->desc_a.config.b_DMA_EN = 1;	//enable this packet's dma
+
+	if (bfin_read_DMA2_IRQ_STATUS() & 0x08) {	//tx dma is running, just return
+		goto out;
+	} else {		//tx dma is not running
+		bfin_write_DMA2_NEXT_DESC_PTR(&(current_tx_ptr->desc_a));
+		bfin_write_DMA2_CONFIG(*((unsigned short *)(&(current_tx_ptr->desc_a.config))));	// dma enabled, read from memory, size is 6
+		// Turn on the EMAC tx
+		bfin_write_EMAC_OPMODE(bfin_read_EMAC_OPMODE() | TE);
+	}
+
+      out:
+	adjust_tx_list();
+	current_tx_ptr = current_tx_ptr->next;
+	dev->trans_start = jiffies;
+	lp->stats.tx_packets++;
+	lp->stats.tx_bytes += (skb->len);
+	return 0;
+}

Hi folks,

Here is the blackfin on-chip ethernet MAC controller driver for Linux.

It's name is blackfin-driver-net-stamp537.patch

[PATCH] Blackfin: on-chip ethernet MAC controller driver

This patch implements the driver necessary use the Analog Devices Blackfin processor's on-chip ethernet MAC controller.

Signed-off-by Bryan Wu <[email protected]>

---

 drivers/net/Kconfig    |   44 ++
 drivers/net/Makefile   |    1
 drivers/net/bfin_mac.c |  988 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 drivers/net/bfin_mac.h |  146 +++++++++
 4 files changed, 1179 insertions(+)

Index: linux-2.6/drivers/net/Kconfig
===================================================================

drivers/net/Kconfig +27 -0

@@ -836,6 +836,50 @@
 	  module, say M here and read <file:Documentation/modules.txt> as well
 	  as <file:Documentation/networking/net-modules.txt>.
 
+config BFIN_MAC
+	tristate "Blackfin 536/537 on-chip mac support"
+	depends on NET_ETHERNET && (BF537 || BF536) && (!BF537_PORT_H)
+	select CRC32
+	select BFIN_MAC_USE_L1 if DMA_UNCACHED_NONE
+	help
+	  This is the driver for blackfin on-chip mac device. Say Y if you want it
+	  compiled into the kernel. This driver is also available as a module
+	  ( = code which can be inserted in and removed from the running kernel
+	  whenever you want). The module will be called bfin_mac.
+
+config BFIN_MAC_USE_L1
+	bool "Use L1 memory for rx/tx packets"
+	depends on BFIN_MAC && BF537
+	default y
+	help
+	  To get maximum network performace, you should use L1 memory as rx/tx buffers.
+	  Say N here if you want to reserve L1 memory for other uses.
+
+config BFIN_TX_DESC_NUM
+	int "Number of transmit buffer packets"
+	depends on BFIN_MAC
+	range 6 10 if BFIN_MAC_USE_L1
+	range 10 100
+	default "10"
+	help
+	  Set the number of buffer packets used in driver.

drivers/net/Kconfig +8 -0

+
+config BFIN_MAC_RMII
+	bool "RMII PHY Interface (EXPERIMENTAL)"
+	depends on BFIN_MAC && EXPERIMENTAL
+	default n
+	help
+	  Use Reduced PHY MII Interface
+
 config SMC9194
 	tristate "SMC 9194 support"

depends on NET_VENDOR_SMC && (ISA || MAC && BROKEN)
Index: linux-2.6/drivers/net/Makefile
===================================================================

drivers/net/Makefile +1 -0

@@ -195,6 +195,7 @@
 obj-$(CONFIG_MYRI10GE) += myri10ge/
 obj-$(CONFIG_SMC91X) += smc91x.o
 obj-$(CONFIG_SMC911X) += smc911x.o
+obj-$(CONFIG_BFIN_MAC) += bfin_mac.o
 obj-$(CONFIG_DM9000) += dm9000.o
 obj-$(CONFIG_FEC_8XX) += fec_8xx/
 obj-$(CONFIG_PASEMI_MAC) += pasemi_mac.o

Index: linux-2.6/drivers/net/bfin_mac.c
===================================================================

drivers/net/bfin_mac.c new file +83 -0

@@ -0,0 +1,988 @@
+/*
+ * File:         drivers/net/bfin_mac.c
+ * Based on:
+ * Author:       Luke Yang <[email protected]>
+ *
+ * Created:
+ * Description:
+ *
+ * Rev:          $Id: bfin_mac.c,v 1.60 2006/12/16 11:23:56 hennerich Exp $
+ *
+ * Modified:
+ *               Copyright 2004-2006 Analog Devices Inc.
+ *
+ * Bugs:         Enter bugs at http://blackfin.uclinux.org/
+ *
+ * This program is free software ;  you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation ;  either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY ;  without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program ;  see the file COPYING.
+ * If not, write to the Free Software Foundation,
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/timer.h>
+#include <linux/errno.h>
+#include <linux/ioport.h>
+#include <linux/crc32.h>
+#include <linux/device.h>
+#include <linux/spinlock.h>
+#include <linux/ethtool.h>
+#include <linux/mii.h>
+
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+
+#include <linux/platform_device.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/dma.h>
+#include <linux/dma-mapping.h>
+
+#include <asm/irq.h>
+#include <asm/blackfin.h>
+#include <asm/delay.h>
+
+#include "bfin_mac.h"
+
+#define CARDNAME "bfin_mac"
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Luke Yang");
+MODULE_DESCRIPTION("Blackfin MAC Driver");
+
+#if defined(CONFIG_BFIN_MAC_USE_L1)
+# define bfin_mac_alloc(dma_handle, size)  l1_data_sram_zalloc(size)
+# define bfin_mac_free(dma_handle, ptr)    l1_data_sram_free(ptr)
+#else
+# define bfin_mac_alloc(dma_handle, size)  dma_alloc_coherent(NULL, size, dma_handle, GFP_DMA)
+# define bfin_mac_free(dma_handle, ptr)    dma_free_coherent(NULL, sizeof(*ptr), ptr, dma_handle)
+#endif
+
+#define PKT_BUF_SZ 1580
+
+static void desc_list_free(void);

drivers/net/bfin_mac.c new file +31 -0

+
+extern void get_bf537_ether_addr(char *addr);
+
+static int desc_list_init(void)
+{
+	struct net_dma_desc_tx *tmp_desc_tx;
+	struct net_dma_desc_rx *tmp_desc_rx;
+	int i;
+	struct sk_buff *new_skb;
+#if !defined(CONFIG_BFIN_MAC_USE_L1)
+	dma_addr_t dma_handle;
+#endif
+
+	tx_desc =
+	    bfin_mac_alloc(&dma_handle,
+			   sizeof(struct net_dma_desc_tx) *
+			   CONFIG_BFIN_TX_DESC_NUM);
+	if (tx_desc == NULL)
+		goto init_error;
+
+	rx_desc =
+	    bfin_mac_alloc(&dma_handle,
+			   sizeof(struct net_dma_desc_rx) *
+			   CONFIG_BFIN_RX_DESC_NUM);
+	if (rx_desc == NULL)
+		goto init_error;
+
+	/* init tx_list */
+	for (i = 0; i < CONFIG_BFIN_TX_DESC_NUM; i++) {
+
+		tmp_desc_tx = tx_desc + i;

drivers/net/bfin_mac.c new file +119 -0

+		tmp_desc_tx->desc_a.config.b_WNR = 0;	//read from memory
+		tmp_desc_tx->desc_a.config.b_WDSIZE = 2;	//wordsize is 32 bits
+		tmp_desc_tx->desc_a.config.b_NDSIZE = 6;	//6 half words is desc size.
+		tmp_desc_tx->desc_a.config.b_FLOW = 7;	//large desc flow
+		tmp_desc_tx->desc_a.next_dma_desc = &(tmp_desc_tx->desc_b);
+
+		tmp_desc_tx->desc_b.start_addr =
+		    (unsigned long)(&(tmp_desc_tx->status));
+		tmp_desc_tx->desc_b.x_count = 0;
+		tmp_desc_tx->desc_b.config.b_DMA_EN = 1;	//enabled
+		tmp_desc_tx->desc_b.config.b_WNR = 1;	//write to memory
+		tmp_desc_tx->desc_b.config.b_WDSIZE = 2;	//wordsize is 32 bits
+		tmp_desc_tx->desc_b.config.b_DI_EN = 0;	//disable interrupt
+		tmp_desc_tx->desc_b.config.b_NDSIZE = 6;
+		tmp_desc_tx->desc_b.config.b_FLOW = 7;	//stop mode
+		tmp_desc_tx->skb = NULL;
+		tx_list_tail->desc_b.next_dma_desc = &(tmp_desc_tx->desc_a);
+		tx_list_tail->next = tmp_desc_tx;
+
+		tx_list_tail = tmp_desc_tx;
+	}
+	tx_list_tail->next = tx_list_head;	/* tx_list is a circle */
+	tx_list_tail->desc_b.next_dma_desc = &(tx_list_head->desc_a);
+	current_tx_ptr = tx_list_head;
+
+	/* init rx_list */
+	for (i = 0; i < CONFIG_BFIN_RX_DESC_NUM; i++) {
+
+		tmp_desc_rx = rx_desc + i;
+
+		if (i == 0) {
+			rx_list_head = tmp_desc_rx;
+			rx_list_tail = tmp_desc_rx;
+		}
+
+		/* allocat a new skb for next time receive */
+		new_skb = dev_alloc_skb(PKT_BUF_SZ + 2);
+		if (!new_skb) {
+			printk(KERN_NOTICE CARDNAME
+			       ": init: low on mem - packet dropped\n");
+			goto init_error;
+		}
+		skb_reserve(new_skb, 2);
+		tmp_desc_rx->skb = new_skb;
+		/* since RXDWA is enabled */
+		tmp_desc_rx->desc_a.start_addr =
+		    (unsigned long)new_skb->data - 2;
+		tmp_desc_rx->desc_a.x_count = 0;
+		tmp_desc_rx->desc_a.config.b_DMA_EN = 1;	//enabled
+		tmp_desc_rx->desc_a.config.b_WNR = 1;	//Write to memory
+		tmp_desc_rx->desc_a.config.b_WDSIZE = 2;	//wordsize is 32 bits
+		tmp_desc_rx->desc_a.config.b_NDSIZE = 6;	//6 half words is desc size.
+		tmp_desc_rx->desc_a.config.b_FLOW = 7;	//large desc flow
+		tmp_desc_rx->desc_a.next_dma_desc = &(tmp_desc_rx->desc_b);
+
+		tmp_desc_rx->desc_b.start_addr =
+		    (unsigned long)(&(tmp_desc_rx->status));
+		tmp_desc_rx->desc_b.x_count = 0;
+		tmp_desc_rx->desc_b.config.b_DMA_EN = 1;	//enabled
+		tmp_desc_rx->desc_b.config.b_WNR = 1;	//Write to memory
+		tmp_desc_rx->desc_b.config.b_WDSIZE = 2;	//wordsize is 32 bits
+		tmp_desc_rx->desc_b.config.b_NDSIZE = 6;
+		tmp_desc_rx->desc_b.config.b_DI_EN = 1;	//enable interrupt
+		tmp_desc_rx->desc_b.config.b_FLOW = 7;	//large mode
+		rx_list_tail->desc_b.next_dma_desc = &(tmp_desc_rx->desc_a);
+
+		rx_list_tail->next = tmp_desc_rx;
+		rx_list_tail = tmp_desc_rx;
+	}
+	rx_list_tail->next = rx_list_head;	/* rx_list is a circle */
+	rx_list_tail->desc_b.next_dma_desc = &(rx_list_head->desc_a);
+	current_rx_ptr = rx_list_head;
+
+	return 0;
+
+      init_error:
+	desc_list_free();
+	printk(KERN_ERR CARDNAME ": kmalloc failed\n");
+	return -ENOMEM;
+}
+
+static void desc_list_free(void)
+{
+	struct net_dma_desc_rx *tmp_desc_rx;
+	struct net_dma_desc_tx *tmp_desc_tx;
+	int i;
+#if !defined(CONFIG_BFIN_MAC_USE_L1)
+	dma_addr_t dma_handle = 0;
+#endif
+
+	if (tx_desc != NULL) {
+		tmp_desc_tx = tx_list_head;
+		for (i = 0; i < CONFIG_BFIN_TX_DESC_NUM; i++) {
+			if (tmp_desc_tx != NULL) {
+				if (tmp_desc_tx->skb) {
+					dev_kfree_skb(tmp_desc_tx->skb);
+					tmp_desc_tx->skb = NULL;
+				}
+
+			}
+			tmp_desc_tx = tmp_desc_tx->next;
+		}
+		bfin_mac_free(dma_handle, tx_desc);
+	}
+
+	if (rx_desc != NULL) {
+		tmp_desc_rx = rx_list_head;
+		for (i = 0; i < CONFIG_BFIN_RX_DESC_NUM; i++) {
+			if (tmp_desc_rx != NULL) {
+				if (tmp_desc_rx->skb) {
+					dev_kfree_skb(tmp_desc_rx->skb);
+					tmp_desc_rx->skb = NULL;
+				}
+			}
+			tmp_desc_rx = tmp_desc_rx->next;
+		}
+		bfin_mac_free(dma_handle, rx_desc);
+	}
+}

Quoted 31 lines · Bryan

drivers/net/Kconfig +31 -0

+config BFIN_MAC
+     tristate "Blackfin 536/537 on-chip mac support"
+     depends on NET_ETHERNET && (BF537 || BF536) && (!BF537_PORT_H)
+     select CRC32
+     select BFIN_MAC_USE_L1 if DMA_UNCACHED_NONE
+     help
+       This is the driver for blackfin on-chip mac device. Say Y if you want it
+       compiled into the kernel. This driver is also available as a module
+       ( = code which can be inserted in and removed from the running kernel
+       whenever you want). The module will be called bfin_mac.
+
+config BFIN_MAC_USE_L1
+     bool "Use L1 memory for rx/tx packets"
+     depends on BFIN_MAC && BF537
+     default y
+     help
+       To get maximum network performace, you should use L1 memory as rx/tx buffers.
+       Say N here if you want to reserve L1 memory for other uses.
+
+config BFIN_TX_DESC_NUM
+     int "Number of transmit buffer packets"
+     depends on BFIN_MAC
+     range 6 10 if BFIN_MAC_USE_L1
+     range 10 100
+     default "10"
+     help
+       Set the number of buffer packets used in driver.
+
+config BFIN_RX_DESC_NUM
+     int "Number of receive buffer packets"
+     depends on BFIN_MAC

drivers/net/Kconfig

Quoted 6 lines

drivers/net/Kconfig +5 -0

+     range 20 100 if BFIN_MAC_USE_L1
+     range 20 800
+     default "20"
+     help
+       Set the number of buffer packets used in driver

The regular practice is to put these in a device include file, and not make them kernel configurable.

Why would you want to make it tuneable at compile time?

Quoted 44 lines · Bryan

Hi folks,

Here is the blackfin on-chip ethernet MAC controller driver for Linux.

Index: linux-2.6/drivers/net/Kconfig
===================================================================
--- linux-2.6.orig/drivers/net/Kconfig 2007-03-01 11:39:14.000000000
+0800 +++ linux-2.6/drivers/net/Kconfig 2007-03-01 11:39:19.000000000
+0800 @@ -836,6 +836,50 @@

drivers/net/Kconfig +7 -0

 	  module, say M here and read <file:Documentation/modules.txt> as well
 	  as <file:Documentation/networking/net-modules.txt>.
 
+config BFIN_MAC
+	tristate "Blackfin 536/537 on-chip mac support"
+	depends on NET_ETHERNET && (BF537 || BF536) && (!BF537_PORT_H)
+	select CRC32
+	select BFIN_MAC_USE_L1 if DMA_UNCACHED_NONE
+	help
+	  This is the driver for blackfin on-chip mac device. Say Y if you want

it + compiled into the kernel. This driver is also available as a
module + ( = code which can be inserted in and removed from the running
kernel + whenever you want). The module will be called bfin_mac.

drivers/net/Kconfig +7 -0

+
+config BFIN_MAC_USE_L1
+	bool "Use L1 memory for rx/tx packets"
+	depends on BFIN_MAC && BF537
+	default y
+	help
+	  To get maximum network performace, you should use L1 memory as rx/tx

buffers. + Say N here if you want to reserve L1 memory for other uses.

drivers/net/Kconfig +14 -0

+
+config BFIN_TX_DESC_NUM
+	int "Number of transmit buffer packets"
+	depends on BFIN_MAC
+	range 6 10 if BFIN_MAC_USE_L1
+	range 10 100
+	default "10"
+	help
+	  Set the number of buffer packets used in driver.
+
+config BFIN_RX_DESC_NUM
+	int "Number of receive buffer packets"
+	depends on BFIN_MAC
+	range 20 100 if BFIN_MAC_USE_L1

drivers/net/Kconfig

Quoted 4 lines

drivers/net/Kconfig +4 -0

+	range 20 800
+	default "20"
+	help
+	  Set the number of buffer packets used in driver

The regular practice is to put these in a device include file, and not make them kernel configurable.
Why would you want to make it tuneable at compile time?

Please do not use mixed case for function or structure member names (see
Coding Style)