aboutsummaryrefslogtreecommitdiff
path: root/drivers/net/mipsnet.c
diff options
context:
space:
mode:
authorRalf Baechle <ralf@linux-mips.org>2008-01-11 17:28:00 +0000
committerDavid S. Miller <davem@davemloft.net>2008-02-03 04:28:10 -0800
commitc800c5c9db9c621b2c1d70c3ae6532fafe2db69d (patch)
tree429dadd456a693c42193c089b6d42d1dbdf1725a /drivers/net/mipsnet.c
parentba64f58ea47de34d864a438d49deccbbaea3f935 (diff)
Fix/Rewrite of the mipsnet driver]
This is Thiemo's patch. ----- Forwarded message from Thiemo Seufer <ths@networkno.de> ----- From: Thiemo Seufer <ths@networkno.de> Date: Sat, 17 Nov 2007 22:29:13 +0000 To: netdev@vger.kernel.org Cc: linux-mips@linux-mips.org, ralf@linux-mips.org Subject: [PATCH, REPOST] Fix/Rewrite of the mipsnet driver Content-Type: text/plain; charset=us-ascii Hello All, currently the mipsnet driver fails after transmitting a number of packages because SKBs are allocated but never freed. I fixed that and coudn't refrain from removing the most egregious warts. - mipsnet.h folded into mipsnet.c, as it doesn't provide any useful external interface. - Free SKB after transmission. - Call free_irq in mipsnet_close, to balance the request_irq in mipsnet_open. - Removed duplicate read of rxDataCount. - Some identifiers are now less verbose. - Removed dead and/or unnecessarily complex code. - Code formatting fixes. Tested on Qemu's mipssim emulation, with this patch it can boot a Debian NFSroot. Thiemo Signed-off-by: Thiemo Seufer <ths@networkno.de> Signed-off-by: Jeff Garzik <jeff@garzik.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/mipsnet.c')
-rw-r--r--drivers/net/mipsnet.c203
1 files changed, 135 insertions, 68 deletions
diff --git a/drivers/net/mipsnet.c b/drivers/net/mipsnet.c
index aafc3ce59cb..6d343efb271 100644
--- a/drivers/net/mipsnet.c
+++ b/drivers/net/mipsnet.c
@@ -4,8 +4,6 @@
* for more details.
*/
-#define DEBUG
-
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
@@ -15,11 +13,93 @@
#include <linux/platform_device.h>
#include <asm/mips-boards/simint.h>
-#include "mipsnet.h" /* actual device IO mapping */
+#define MIPSNET_VERSION "2007-11-17"
+
+/*
+ * Net status/control block as seen by sw in the core.
+ */
+struct mipsnet_regs {
+ /*
+ * Device info for probing, reads as MIPSNET%d where %d is some
+ * form of version.
+ */
+ u64 devId; /*0x00 */
-#define MIPSNET_VERSION "2005-06-20"
+ /*
+ * read only busy flag.
+ * Set and cleared by the Net Device to indicate that an rx or a tx
+ * is in progress.
+ */
+ u32 busy; /*0x08 */
-#define mipsnet_reg_address(dev, field) (dev->base_addr + field_offset(field))
+ /*
+ * Set by the Net Device.
+ * The device will set it once data has been received.
+ * The value is the number of bytes that should be read from
+ * rxDataBuffer. The value will decrease till 0 until all the data
+ * from rxDataBuffer has been read.
+ */
+ u32 rxDataCount; /*0x0c */
+#define MIPSNET_MAX_RXTX_DATACOUNT (1 << 16)
+
+ /*
+ * Settable from the MIPS core, cleared by the Net Device.
+ * The core should set the number of bytes it wants to send,
+ * then it should write those bytes of data to txDataBuffer.
+ * The device will clear txDataCount has been processed (not
+ * necessarily sent).
+ */
+ u32 txDataCount; /*0x10 */
+
+ /*
+ * Interrupt control
+ *
+ * Used to clear the interrupted generated by this dev.
+ * Write a 1 to clear the interrupt. (except bit31).
+ *
+ * Bit0 is set if it was a tx-done interrupt.
+ * Bit1 is set when new rx-data is available.
+ * Until this bit is cleared there will be no other RXs.
+ *
+ * Bit31 is used for testing, it clears after a read.
+ * Writing 1 to this bit will cause an interrupt to be generated.
+ * To clear the test interrupt, write 0 to this register.
+ */
+ u32 interruptControl; /*0x14 */
+#define MIPSNET_INTCTL_TXDONE (1u << 0)
+#define MIPSNET_INTCTL_RXDONE (1u << 1)
+#define MIPSNET_INTCTL_TESTBIT (1u << 31)
+
+ /*
+ * Readonly core-specific interrupt info for the device to signal
+ * the core. The meaning of the contents of this field might change.
+ */
+ /* XXX: the whole memIntf interrupt scheme is messy: the device
+ * should have no control what so ever of what VPE/register set is
+ * being used.
+ * The MemIntf should only expose interrupt lines, and something in
+ * the config should be responsible for the line<->core/vpe bindings.
+ */
+ u32 interruptInfo; /*0x18 */
+
+ /*
+ * This is where the received data is read out.
+ * There is more data to read until rxDataReady is 0.
+ * Only 1 byte at this regs offset is used.
+ */
+ u32 rxDataBuffer; /*0x1c */
+
+ /*
+ * This is where the data to transmit is written.
+ * Data should be written for the amount specified in the
+ * txDataCount register.
+ * Only 1 byte at this regs offset is used.
+ */
+ u32 txDataBuffer; /*0x20 */
+};
+
+#define regaddr(dev, field) \
+ (dev->base_addr + offsetof(struct mipsnet_regs, field))
static char mipsnet_string[] = "mipsnet";
@@ -29,32 +109,27 @@ static char mipsnet_string[] = "mipsnet";
static int ioiocpy_frommipsnet(struct net_device *dev, unsigned char *kdata,
int len)
{
- uint32_t available_len = inl(mipsnet_reg_address(dev, rxDataCount));
-
- if (available_len < len)
- return -EFAULT;
-
for (; len > 0; len--, kdata++)
- *kdata = inb(mipsnet_reg_address(dev, rxDataBuffer));
+ *kdata = inb(regaddr(dev, rxDataBuffer));
- return inl(mipsnet_reg_address(dev, rxDataCount));
+ return inl(regaddr(dev, rxDataCount));
}
-static inline ssize_t mipsnet_put_todevice(struct net_device *dev,
+static inline void mipsnet_put_todevice(struct net_device *dev,
struct sk_buff *skb)
{
int count_to_go = skb->len;
char *buf_ptr = skb->data;
- outl(skb->len, mipsnet_reg_address(dev, txDataCount));
+ outl(skb->len, regaddr(dev, txDataCount));
for (; count_to_go; buf_ptr++, count_to_go--)
- outb(*buf_ptr, mipsnet_reg_address(dev, txDataBuffer));
+ outb(*buf_ptr, regaddr(dev, txDataBuffer));
dev->stats.tx_packets++;
dev->stats.tx_bytes += skb->len;
- return skb->len;
+ dev_kfree_skb(skb);
}
static int mipsnet_xmit(struct sk_buff *skb, struct net_device *dev)
@@ -69,18 +144,20 @@ static int mipsnet_xmit(struct sk_buff *skb, struct net_device *dev)
return 0;
}
-static inline ssize_t mipsnet_get_fromdev(struct net_device *dev, size_t count)
+static inline ssize_t mipsnet_get_fromdev(struct net_device *dev, size_t len)
{
struct sk_buff *skb;
- size_t len = count;
- skb = alloc_skb(len + 2, GFP_KERNEL);
+ if (!len)
+ return len;
+
+ skb = dev_alloc_skb(len + NET_IP_ALIGN);
if (!skb) {
dev->stats.rx_dropped++;
return -ENOMEM;
}
- skb_reserve(skb, 2);
+ skb_reserve(skb, NET_IP_ALIGN);
if (ioiocpy_frommipsnet(dev, skb_put(skb, len), len))
return -EFAULT;
@@ -92,50 +169,42 @@ static inline ssize_t mipsnet_get_fromdev(struct net_device *dev, size_t count)
dev->stats.rx_packets++;
dev->stats.rx_bytes += len;
- return count;
+ return len;
}
static irqreturn_t mipsnet_interrupt(int irq, void *dev_id)
{
struct net_device *dev = dev_id;
-
- irqreturn_t retval = IRQ_NONE;
- uint64_t interruptFlags;
-
- if (irq == dev->irq) {
- retval = IRQ_HANDLED;
-
- interruptFlags =
- inl(mipsnet_reg_address(dev, interruptControl));
-
- if (interruptFlags & MIPSNET_INTCTL_TXDONE) {
- outl(MIPSNET_INTCTL_TXDONE,
- mipsnet_reg_address(dev, interruptControl));
- /* only one packet at a time, we are done. */
- netif_wake_queue(dev);
- } else if (interruptFlags & MIPSNET_INTCTL_RXDONE) {
- mipsnet_get_fromdev(dev,
- inl(mipsnet_reg_address(dev, rxDataCount)));
- outl(MIPSNET_INTCTL_RXDONE,
- mipsnet_reg_address(dev, interruptControl));
-
- } else if (interruptFlags & MIPSNET_INTCTL_TESTBIT) {
- /*
- * TESTBIT is cleared on read.
- * And takes effect after a write with 0
- */
- outl(0, mipsnet_reg_address(dev, interruptControl));
- } else {
- /* Maybe shared IRQ, just ignore, no clearing. */
- retval = IRQ_NONE;
- }
-
- } else {
- printk(KERN_INFO "%s: %s(): irq %d for unknown device\n",
- dev->name, __FUNCTION__, irq);
- retval = IRQ_NONE;
+ u32 int_flags;
+ irqreturn_t ret = IRQ_NONE;
+
+ if (irq != dev->irq)
+ goto out_badirq;
+
+ /* TESTBIT is cleared on read. */
+ int_flags = inl(regaddr(dev, interruptControl));
+ if (int_flags & MIPSNET_INTCTL_TESTBIT) {
+ /* TESTBIT takes effect after a write with 0. */
+ outl(0, regaddr(dev, interruptControl));
+ ret = IRQ_HANDLED;
+ } else if (int_flags & MIPSNET_INTCTL_TXDONE) {
+ /* Only one packet at a time, we are done. */
+ dev->stats.tx_packets++;
+ netif_wake_queue(dev);
+ outl(MIPSNET_INTCTL_TXDONE,
+ regaddr(dev, interruptControl));
+ ret = IRQ_HANDLED;
+ } else if (int_flags & MIPSNET_INTCTL_RXDONE) {
+ mipsnet_get_fromdev(dev, inl(regaddr(dev, rxDataCount)));
+ outl(MIPSNET_INTCTL_RXDONE, regaddr(dev, interruptControl));
+ ret = IRQ_HANDLED;
}
- return retval;
+ return ret;
+
+out_badirq:
+ printk(KERN_INFO "%s: %s(): irq %d for unknown device\n",
+ dev->name, __FUNCTION__, irq);
+ return ret;
}
static int mipsnet_open(struct net_device *dev)
@@ -144,18 +213,15 @@ static int mipsnet_open(struct net_device *dev)
err = request_irq(dev->irq, &mipsnet_interrupt,
IRQF_SHARED, dev->name, (void *) dev);
-
if (err) {
- release_region(dev->base_addr, MIPSNET_IO_EXTENT);
+ release_region(dev->base_addr, sizeof(struct mipsnet_regs));
return err;
}
netif_start_queue(dev);
/* test interrupt handler */
- outl(MIPSNET_INTCTL_TESTBIT,
- mipsnet_reg_address(dev, interruptControl));
-
+ outl(MIPSNET_INTCTL_TESTBIT, regaddr(dev, interruptControl));
return 0;
}
@@ -163,7 +229,7 @@ static int mipsnet_open(struct net_device *dev)
static int mipsnet_close(struct net_device *dev)
{
netif_stop_queue(dev);
-
+ free_irq(dev->irq, dev);
return 0;
}
@@ -194,10 +260,11 @@ static int __init mipsnet_probe(struct device *dev)
*/
netdev->base_addr = 0x4200;
netdev->irq = MIPS_CPU_IRQ_BASE + MIPSCPU_INT_MB0 +
- inl(mipsnet_reg_address(netdev, interruptInfo));
+ inl(regaddr(netdev, interruptInfo));
/* Get the io region now, get irq on open() */
- if (!request_region(netdev->base_addr, MIPSNET_IO_EXTENT, "mipsnet")) {
+ if (!request_region(netdev->base_addr, sizeof(struct mipsnet_regs),
+ "mipsnet")) {
err = -EBUSY;
goto out_free_netdev;
}
@@ -217,7 +284,7 @@ static int __init mipsnet_probe(struct device *dev)
return 0;
out_free_region:
- release_region(netdev->base_addr, MIPSNET_IO_EXTENT);
+ release_region(netdev->base_addr, sizeof(struct mipsnet_regs));
out_free_netdev:
free_netdev(netdev);
@@ -231,7 +298,7 @@ static int __devexit mipsnet_device_remove(struct device *device)
struct net_device *dev = dev_get_drvdata(device);
unregister_netdev(dev);
- release_region(dev->base_addr, MIPSNET_IO_EXTENT);
+ release_region(dev->base_addr, sizeof(struct mipsnet_regs));
free_netdev(dev);
dev_set_drvdata(device, NULL);