[ 66/84] r8169: Rx FIFO overflow fixes.

Greg Kroah-Hartman
2012-10-11T02:20:00Z

From: Francois Romieu <romieu@fr.zoreil.com>

commit 811fd3010cf512f2e23e6c4c912aad54516dc706 upstream.

Realtek has specified that the post 8168c gigabit chips and the post
8105e fast ethernet chips recover automatically from a Rx FIFO overflow.
The driver does not need to clear the RxFIFOOver bit of IntrStatus and
it should rather avoid messing it.

The implementation deserves some explanation:
1. events outside of the intr_event bit mask are now ignored. It enforces
a no-processing policy for the events that either should not be there
or should be ignored.

2. RxFIFOOver was already ignored in rtl_cfg_infos[RTL_CFG_1] for the
whole 8168 line of chips with two exceptions:
- RTL_GIGA_MAC_VER_22 since b5ba6d12bdac21bc0620a5089e0f24e362645efd
("use RxFIFO overflow workaround for 8168c chipset.").
This one should now be correctly handled.
- RTL_GIGA_MAC_VER_11 (8168b) which requires a different Rx FIFO
overflow processing.

Though it does not conform to Realtek suggestion above, the updated
driver includes no change for RTL_GIGA_MAC_VER_12 and RTL_GIGA_MAC_VER_17.
Both are 8168b. RTL_GIGA_MAC_VER_12 is common and a bit old so I'd rather
wait for experimental evidence that the change suggested by Realtek really
helps or does not hurt in unexpected ways.

Removed case statements in rtl8169_interrupt are only 8168 relevant.

3. RxFIFOOver is masked for post 8105e 810x chips, namely the sole 8105e
(RTL_GIGA_MAC_VER_30) itself.

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Cc: hayeswang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/r8169.c | 54 +++++++++++++++++++++++-----------------------------
1 file changed, 24 insertions(+), 30 deletions(-)

--- a/drivers/net/r8169.c
+++ b/drivers/net/r8169.c
@@ -1088,17 +1088,21 @@ static u8 rtl8168d_efuse_read(void __iom
return value;
}

-static void rtl8169_irq_mask_and_ack(void __iomem *ioaddr)
+static void rtl8169_irq_mask_and_ack(struct rtl8169_private *tp)
{
- RTL_W16(IntrMask, 0x0000);
+ void __iomem *ioaddr = tp->mmio_addr;

- RTL_W16(IntrStatus, 0xffff);
+ RTL_W16(IntrMask, 0x0000);
+ RTL_W16(IntrStatus, tp->intr_event);
+ RTL_R8(ChipCmd);
}

-static void rtl8169_asic_down(void __iomem *ioaddr)
+static void rtl8169_asic_down(struct rtl8169_private *tp)
{
+ void __iomem *ioaddr = tp->mmio_addr;
+
RTL_W8(ChipCmd, 0x00);
- rtl8169_irq_mask_and_ack(ioaddr);
+ rtl8169_irq_mask_and_ack(tp);
RTL_R16(CPlusCmd);
}

@@ -3817,7 +3821,7 @@ static void rtl8169_hw_reset(struct rtl8
void __iomem *ioaddr = tp->mmio_addr;

/* Disable interrupts */
- rtl8169_irq_mask_and_ack(ioaddr);
+ rtl8169_irq_mask_and_ack(tp);

if (tp->mac_version == RTL_GIGA_MAC_VER_27 ||
tp->mac_version == RTL_GIGA_MAC_VER_28 ||
@@ -4284,8 +4288,7 @@ static void rtl_hw_start_8168(struct net
RTL_W16(IntrMitigate, 0x5151);

/* Work around for RxFIFO overflow. */
- if (tp->mac_version == RTL_GIGA_MAC_VER_11 ||
- tp->mac_version == RTL_GIGA_MAC_VER_22) {
+ if (tp->mac_version == RTL_GIGA_MAC_VER_11) {
tp->intr_event |= RxFIFOOver | PCSTimeout;
tp->intr_event &= ~RxOverflow;
}
@@ -4467,6 +4470,11 @@ static void rtl_hw_start_8101(struct net
void __iomem *ioaddr = tp->mmio_addr;
struct pci_dev *pdev = tp->pci_dev;

+ if (tp->mac_version >= RTL_GIGA_MAC_VER_30) {
+ tp->intr_event &= ~RxFIFOOver;
+ tp->napi_event &= ~RxFIFOOver;
+ }
+
if (tp->mac_version == RTL_GIGA_MAC_VER_13 ||
tp->mac_version == RTL_GIGA_MAC_VER_16) {
int cap = tp->pcie_cap;
@@ -4738,7 +4746,7 @@ static void rtl8169_wait_for_quiescence(
/* Wait for any pending NAPI task to complete */
napi_disable(&tp->napi);

- rtl8169_irq_mask_and_ack(ioaddr);
+ rtl8169_irq_mask_and_ack(tp);

tp->intr_mask = 0xffff;
RTL_W16(IntrMask, tp->intr_event);
@@ -5200,13 +5208,17 @@ static irqreturn_t rtl8169_interrupt(int
*/
status = RTL_R16(IntrStatus);
while (status && status != 0xffff) {
+ status &= tp->intr_event;
+ if (!status)
+ break;
+
handled = 1;

/* Handle all of the error cases first. These will reset
* the chip, so just exit the loop.
*/
if (unlikely(!netif_running(dev))) {
- rtl8169_asic_down(ioaddr);
+ rtl8169_asic_down(tp);
break;
}

@@ -5214,27 +5226,9 @@ static irqreturn_t rtl8169_interrupt(int
switch (tp->mac_version) {
/* Work around for rx fifo overflow */
case RTL_GIGA_MAC_VER_11:
- case RTL_GIGA_MAC_VER_22:
- case RTL_GIGA_MAC_VER_26:
netif_stop_queue(dev);
rtl8169_tx_timeout(dev);
goto done;
- /* Testers needed. */
- case RTL_GIGA_MAC_VER_17:
- case RTL_GIGA_MAC_VER_19:
- case RTL_GIGA_MAC_VER_20:
- case RTL_GIGA_MAC_VER_21:
- case RTL_GIGA_MAC_VER_23:
- case RTL_GIGA_MAC_VER_24:
- case RTL_GIGA_MAC_VER_27:
- case RTL_GIGA_MAC_VER_28:
- case RTL_GIGA_MAC_VER_31:
- /* Experimental science. Pktgen proof. */
- case RTL_GIGA_MAC_VER_12:
- case RTL_GIGA_MAC_VER_25:
- if (status == RxFIFOOver)
- goto done;
- break;
default:
break;
}
@@ -5329,7 +5323,7 @@ static void rtl8169_down(struct net_devi

spin_lock_irq(&tp->lock);

- rtl8169_asic_down(ioaddr);
+ rtl8169_asic_down(tp);
/*
* At this point device interrupts can not be enabled in any function,
* as netif_running is not true (rtl8169_interrupt, rtl8169_reset_task,
@@ -5583,7 +5577,7 @@ static void rtl_shutdown(struct pci_dev

spin_lock_irq(&tp->lock);

- rtl8169_asic_down(ioaddr);
+ rtl8169_asic_down(tp);

spin_unlock_irq(&tp->lock);