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path: root/drivers/net/tg3.h
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* [TG3]: Exit irq handler during chip reset.Michael Chan2007-03-25
| | | | | | | | | | | | | | | | | | | | | On most tg3 chips, the memory enable bit in the PCI command register gets cleared during chip reset and must be restored before accessing PCI registers using memory cycles. The chip does not generate interrupt during chip reset, but the irq handler can still be called because of irq sharing or irqpoll. Reading a register in the irq handler can cause a master abort in this scenario and may result in a crash on some architectures. Use the TG3_FLAG_CHIP_RESETTING flag to tell the irq handler to exit without touching any registers. The checking of the flag is in the "slow" path of the irq handler and will not affect normal performance. The msi handler is not shared and therefore does not require checking the flag. Thanks to Bernhard Walle <bwalle@suse.de> for reporting the problem. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Eliminate the unused TG3_FLAG_SPLIT_MODE flag.Michael Chan2007-03-25
| | | | | | | | This flag to support multiple PCIX split completions was never used because of hardware bugs. This will make room for a new flag. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: TSO workaround fixes.Michael Chan2007-02-26
| | | | | | | | | | | | | | | | 1. Add race condition check after netif_stop_queue(). tg3_tx() runs without netif_tx_lock and can race with tg3_start_xmit_dma_bug() -> tg3_tso_bug(). 2. Firmware TSO in 5703/5704/5705 also have the same TSO limitation, i.e. they cannot handle TSO headers bigger than 80 bytes. Rename TG3_FL2_HW_TSO_1_BUG to TG3_FL2_TSO_BUG and set this flag on these chips as well. 3. Update version to 3.74. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Use constant for PHY register 0x1e.Michael Chan2007-02-13
| | | | | Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add PHY workaround for 5755M.Michael Chan2007-01-09
| | | | | | | | | | Some PHY trim values need to be fine-tuned on 5755M to be IEEE-compliant. Update version to 3.72. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Power down/up 5906 PHY correctly.Michael Chan2006-12-18
| | | | | | | | The 5906 PHY requires a special register bit to power down and up the PHY. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add TG3_FLG2_IS_NIC flag.Michael Chan2006-12-07
| | | | | | | | | | | Add Tg3_FLG2_IS_NIC flag to unambiguously determine whether the device is NIC or onboard. Previously, the EEPROM_WRITE_PROT flag was overloaded to also mean onboard. With the separation, we can support some devices that are onboard but do not use eeprom write protect. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add 5709 self-test support.Michael Chan2006-09-28
| | | | | Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add 5709 PHY support.Michael Chan2006-09-28
| | | | | | | Add support for the 5709 10/100 PHY. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add basic 5906 support.Michael Chan2006-09-28
| | | | | | | | | Add support for the new 5709 device. This is a new 10/100 Mbps chip. The mailbox access and firmware interface are quite different from all other tg3 chips. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add 5722 and 5756 support.Michael Chan2006-09-28
| | | | | | | Add IDs to support 5722 and 5756. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Improve ASF heartbeat.Michael Chan2006-09-28
| | | | | | | | | | | | | | | | | Change to a different ASF heartbeat message code to improve reliability. There were some reports of unintended resets on real time kernels where the timer may be slow and cause the heartbeat to be late. Netpoll will also have the same problem because the timer irq will be unavailable. Using the new heartbeat code, the ASF firmware will also check the ring condition before resetting the chip when the heartbeat is expiring. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Improve 5704S autoneg.Michael Chan2006-09-28
| | | | | | | | | | Improve 5704S autoneg logic by using a serdes_counter field to keep track of the transient states. This eliminates a 200 msec busy loop in the code. Autoneg will take its course without the driver busy waiting for it to finish. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Fix tx race conditionMichael Chan2006-08-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a subtle race condition between tg3_start_xmit() and tg3_tx() discovered by Herbert Xu <herbert@gondor.apana.org.au>: CPU0 CPU1 tg3_start_xmit() if (tx_ring_full) { tx_lock tg3_tx() if (!netif_queue_stopped) netif_stop_queue() if (!tx_ring_full) update_tx_ring netif_wake_queue() tx_unlock } Even though tx_ring is updated before the if statement in tg3_tx() in program order, it can be re-ordered by the CPU as shown above. This scenario can cause the tx queue to be stopped forever if tg3_tx() has just freed up the entire tx_ring. The possibility of this happening should be very rare though. The following changes are made: 1. Add memory barrier to fix the above race condition. 2. Eliminate the private tx_lock altogether and rely solely on netif_tx_lock. This eliminates one spinlock in tg3_start_xmit() when the ring is full. 3. Because of 2, use netif_tx_lock in tg3_tx() before calling netif_wake_queue(). 4. Change TX_BUFFS_AVAIL to an inline function with a memory barrier. Herbert and David suggested using the memory barrier instead of volatile. 5. Check for the full wake queue condition before getting netif_tx_lock in tg3_tx(). This reduces the number of unnecessary spinlocks when the tx ring is full in a steady-state condition. 6. Update version to 3.65. Signed-off-by: Michael Chan <mchan@broadcom.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add TSO workaround using GSOMichael Chan2006-06-30
| | | | | | | | | | | | | | | | | Use GSO to workaround a rare TSO bug on some chips. This hardware bug may be triggered when the TSO header size is greater than 80 bytes. When this condition is detected in a TSO packet, the driver will use GSO to segment the packet to workaround the hardware bug. Thanks to Juergen Kreileder <jk@blackdown.de> for reporting the problem and collecting traces to help debug the problem. And thanks to Herbert Xu <herbert@gondor.apana.org.au> for providing the GSO mechanism that happens to be the perfect workaround for this problem. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Turn on hw fix for ASF problemsMichael Chan2006-06-30
| | | | | | | Clear a bit to enable a hardware fix for some ASF related problem. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add rx BD workaroundMichael Chan2006-06-30
| | | | | | | | | Add workaround to limit the burst size of rx BDs being DMA'ed to the chip. This works around hardware errata on a number of 5750, 5752, and 5755 chips. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Convert to non-LLTXMichael Chan2006-06-18
| | | | | | | | | | | | | | | | | | Herbert Xu pointed out that it is unsafe to call netif_tx_disable() from LLTX drivers because it uses dev->xmit_lock to synchronize whereas LLTX drivers use private locks. Convert tg3 to non-LLTX to fix this issue. tg3 is a lockless driver where hard_start_xmit and tx completion handling can run concurrently under normal conditions. A tx_lock is only needed to prevent netif_stop_queue and netif_wake_queue race condtions when the queue is full. So whether we use LLTX or non-LLTX, it makes practically no difference. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add recovery logic when MMIOs are re-orderedMichael Chan2006-06-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add recovery logic when we suspect that the system is re-ordering MMIOs. Re-ordered MMIOs to the send mailbox can cause bogus tx completions and hit BUG_ON() in the tx completion path. tg3 already has logic to handle re-ordered MMIOs by flushing the MMIOs that must be strictly ordered (such as the send mailbox). Determining when to enable the flush is currently a manual process of adding known chipsets to a list. The new code replaces the BUG_ON() in the tx completion path with the call to tg3_tx_recover(). It will set the TG3_FLAG_MBOX_WRITE_REORDER flag and reset the chip later in the workqueue to recover and start flushing MMIOs to the mailbox. A message to report the problem will be printed. We will then decide whether or not to add the host bridge to the list of chipsets that do re-ordering. We may add some additional code later to print the host bridge's ID so that the user can report it more easily. The assumption that re-ordering can only happen on x86 systems is also removed. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Handle Sun onboard tg3 chips more correctly.David S. Miller2006-06-09
| | | | | | | | | | | | | | | | | | | | | Get rid of all the SUN_570X logic and instead: 1) Make sure MEMARB_ENABLE is set when we probe the SRAM for config information. If that is off we will get timeouts. 2) Always try to sync with the firmware, if there is no firmware running do not treat it as an error and instead just report it the first time we notice this condition. 3) If there is no valid SRAM signature, assume the device is onboard by setting TG3_FLAG_EEPROM_WRITE_PROT. Update driver version and release date. With help from Michael Chan and Fabio Massimo Di Nitto. Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add phy workaroundMichael Chan2006-04-29
| | | | | | | Add some PHY workaround code to reduce jitter on some PHYs. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Speed up SRAM access (2nd version)Michael Chan2006-04-10
| | | | | | | | | | | | | | | | | | | | | | | | Speed up SRAM read and write functions if possible by using MMIO instead of config. cycles. With this change, the post reset signature done at the end of D3 power change must now be moved before the D3 power change. IBM reported a problem on powerpc blades during ethtool self test that was caused by the memory test taking excessively long. Config. cycles are very slow on powerpc and the memory test can take more than 10 seconds to complete using config. cycles. David Miller informed me that an earlier version of the patch caused problems on sparc64 systems with built-in tg3 chips. This version fixes the problem by excluding all SUN built-in tg3 chips from doing MMIO SRAM access. TG3_FLAG_EEPROM_WRITE_PROT is also set unconditionally when TG3_FLG2_SUN_570X is set. This should be sane as all SUN chips are built-in and do not require Vaux switching. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Kill some less useful flagsMichael Chan2006-04-10
| | | | | | | | Kill the TG3_FLAG_NO_{TX|RX}_PSEUDO_CSUM flags because they are not very useful. This will free up some bits for new flags. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add 5755 nvram supportMichael Chan2006-03-23
| | | | | | | Add 5755 nvram support. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add 5755 supportMichael Chan2006-03-23
| | | | | | | Add support for new chip 5755 which is very similar to 5787. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add firmware version infoMichael Chan2006-03-21
| | | | | | | Add fw_version information to ethtool -i. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add new one-shot MSI handlerMichael Chan2006-03-21
| | | | | | | | | | | Support one-shot MSI on 5787. This one-shot MSI idea is credited to David Miller. In this mode, MSI disables itself automatically after it is generated, saving the driver a register access to disable it for NAPI. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add new hard_start_xmitMichael Chan2006-03-21
| | | | | | | | | | | | | Support 5787 hardware TSO using a new flag TG3_FLG2_HW_TSO_2. Since the TSO interface is slightly different and these chips have finally fixed the 4GB DMA problem and do not have the 40-bit DMA problem, a new hard_start_xmit is used for these chips. All previous chips will use the old hard_start_xmit that is now renamed tg3_start_xmit_dma_bug(). Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add 5787 nvram supportMichael Chan2006-03-21
| | | | | | | Support additional nvrams and new nvram format for 5787 and 5754. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add 5787 and 5754 basic supportMichael Chan2006-03-21
| | | | | | | Add basic support for 2 new chips 5787 and 5754. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: 40-bit DMA workaround part 2Michael Chan2006-03-19
| | | | | | | | | | | | | | | | | The 40-bit DMA workaround recently implemented for 5714, 5715, and 5780 needs to be expanded because there may be other tg3 devices behind the EPB Express to PCIX bridge in the 5780 class device. For example, some 4-port card or mother board designs have 5704 behind the 5714. All devices behind the EPB require the 40-bit DMA workaround. Thanks to Chris Elmquist again for reporting the problem and testing the patch. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Flush tg3_reset_task()Michael Chan2006-02-02
| | | | | | | | | | | | | | Make sure tg3_reset_task() is flushed in the close and suspend paths as noted by Jeff Garzik. In the close path, calling flush_scheduled_work() may cause deadlock if linkwatch_event() is on the workqueue. linkwatch_event() will try to get the rtnl_lock() which is already held by tg3_close(). So instead, we set a flag in tg3_reset_task() and tg3_close() polls the flag until it is cleared. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Refine nvram lockingMichael Chan2006-01-17
| | | | | | | | | | | | | | | Add nvram lock count so that calls to tg3_nvram_lock()/unlock() can be nested. Add error checking to all callers of tg3_nvram_lock() where appropriate. To prevent nvram lock failures after halting the firmware, it is also necessary to release firmware's nvram lock in tg3_halt_cpu(). Update version to 3.48. Based on David Miller's initial patch. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: ethtool -d hangs PCIe systemsChris Elmquist2005-12-28
| | | | | | | | | | | | Resubmitting after recommendation to use GET_REG32_1() instead of GET_REG32_LOOP(..., 1). Retested. Problem remains fixed. Prevent tg3_get_regs() from reading reserved and undocumented registers at RX_CPU_BASE and TX_CPU_BASE offsets which caused hostile behavior on PCIe platforms. Acked-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Fix low power stateMichael Chan2005-12-14
| | | | | | | | | | | | | | | | | | | | Fix the following bugs in tg3_set_power_state(): 1. Both WOL and ASF flags require switching to aux power. 2. Add a missing handshake with firmware to enable WOL. 3. Turn off the PHY if both WOL and ASF are disabled. 4. Add nvram arbitration before halting the firmware. 5. Fix tg3_setup_copper_phy() to switch to 100Mbps when changing to low power state. Update revision and date. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [PATCH] tg3: fix ASF heartbeatMichael Chan2005-10-28
| | | | | | | | | | | | | | Change the ASF heart beat to 5 seconds for faster detection of system crash. The driver sends the heartbeat every 2 seconds and the ASF firmware will timeout and reset the device if no heartbeat is received after 5 seconds. The old scheme of 2 minutes is ineffective. tg3_write_mem_fast() is added to speed up the IO to send the heartbeat. When no workaround is needed, it will use direct MMIO to memory space to write to memory. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
* [PATCH] tg3: add 5714/5715 supportMichael Chan2005-10-28
| | | | | | | | | Add complete support for 5714/5715. These chips are very similar to 5780 so the changes are very trivial. A TG3_FLG2_5780_CLASS flag is added to identify these chips. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
* [TG3]: 5780 PHY fixesMichael Chan2005-09-27
| | | | | | | | | | | | | | | | | | | | | | | | Fix 5780 PHY related problems: 1. MAC_RX_MODE reset must be done before setting up the MAC_MODE register on 5705_PLUS chips or the chip will stop receiving after a while. The MAC_RX_MODE reset is needed to prevent intermittently losing the first receive packet on serdes chips. 2. Skip MAC loopback test on 5780 because of hardware errata. Normal traffic including PHY loopback is not affected by the errata. 3. PHY loopback fails intermittently on 5708S and this is fixed by putting the PHY in loopback mode first before programming the MAC mode register. A MAC_RX_MODE reset is also added. 4. Return -EINVAL in tg3_nway_reset() if device is in TBI mode. Allow nway_reset if 5780S is in parallel detect mode. 5. Add missing PHY IDs in KNOWN_PHY_ID() macro. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add indirect register method for 5703 behind ICHMichael Chan2005-08-29
| | | | | | | | | | | | | | | | | | | | This patch adds the new workaround for 5703 A1/A2 if it is behind certain ICH bridges. The workaround disables memory and uses config. cycles only to access all registers. The 5702/03 chips can mistakenly decode the special cycles from the ICH chipsets as memory write cycles, causing corruption of register and memory space. Only certain ICH bridges will drive special cycles with non-zero data during the address phase which can fall within the 5703's address range. This is not an ICH bug as the PCI spec allows non-zero address during special cycles. However, only these ICH bridges are known to drive non-zero addresses during special cycles. The indirect_lock is also changed to spin_lock_irqsave from spin_lock_bh because it is used in irq handler when using the indirect method to disable interrupts. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add mailbox read methodMichael Chan2005-08-29
| | | | | | | | This patch adds the mailbox read method and also adds an inline function tw32_mailbox_f() for mailbox writes that require read flush. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add basic register access function pointersMichael Chan2005-08-29
| | | | | | | | | | | | | | This patch adds the basic function pointers to do register accesses in the fast path. This was suggested by David Miller. The idea is that various register access methods for different hardware errata can easily be implemented with these function pointers and performance will not be degraded on chips that use normal register access methods. The various register read write macros (e.g. tw32, tr32, tw32_mailbox) are redefined to call the function pointers. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: add 5780 fiber supportMichael Chan2005-07-25
| | | | | | | | | | Add 5780S support by adding a new tg3_setup_fiber_mii_phy() function and a timer function for parallel link detection. 5780S uses standard MII registers for 1000BaseX and runs in GMII mode as opposed to TBI mode on older serdes chips. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: consolidate all DMA water mark settingsMichael Chan2005-07-25
| | | | | | | | Consolidate all DMA watermark settings for standard and jumbo frames on all chips in tg3_init_bufmgr_config() and add new settings for 5780. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: add variable buffer size for standard ringMichael Chan2005-07-25
| | | | | | | | Add a new rx_pkt_buf_sz to the tg3 structure to support variable buffer sizes on the standard ring. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: add 5780 basic jumbo frame supportMichael Chan2005-07-25
| | | | | | | | | | | | Add basic jumbo frames support for 5780. This chip supports jumbo frames on the standard receive ring without the jumbo ring. The TG3_FLAG_JUMBO_ENABLE is changed to TG3_FLAG_JUMBO_RING_ENABLE to indicate using the jumbo ring on 5704 and older chips. A new TG3_FLG2_JUMBO_CAPABLE flag is added to indicate jumbo frames support with or without the jumbo ring. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: add 5780 basic supportMichael Chan2005-07-25
| | | | | | | Add 5780 PCI IDs, chip IDs, and other basic support. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: support for ethtool -CMichael Chan2005-07-05
| | | | | | | Add support for ethtool -C with verification of user parameters. Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Eliminate all hw IRQ handler spinlocks.David S. Miller2005-06-24
| | | | | | | | | | | | | | | | | | | | | Move all driver spinlocks to be taken at sw IRQ context only. This fixes the skb_copy() we were doing with hw IRQs disabled (which is illegal and triggers a BUG() with HIGHMEM enabled). It also simplifies the locking all over the driver tremendously. We accomplish this feat by creating a special sequence to synchronize with the hw IRQ handler using a binary state and synchronize_irq(). This idea is from Herbert Xu. Thanks to Michael Chan for helping to track down all of the race conditions in initial versions of this code. Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Set minimal hw interrupt mitigation.David S. Miller2005-05-19
| | | | | | | | | | | | | | | | | | | Even though we do software interrupt mitigation via NAPI, it still helps to have some minimal hw assisted mitigation. This helps, particularly, on systems where register I/O overhead is much greater than the CPU horsepower. For example, it helps on NUMA systems. In such cases the PIO overhead to disable interrupts for NAPI accounts for the majority of the packet processing cost. The CPU is fast enough such that only a single packet is processed by each NAPI poll call. Thanks to Michael Chan for reviewing this patch. Signed-off-by: David S. Miller <davem@davemloft.net>
* [TG3]: Add tagged status support.David S. Miller2005-05-19
| | | | | | | | | | | | | | | | | | | | | | | | | When supported, use the TAGGED interrupt processing support the chip provides. In this mode, instead of a "on/off" binary semaphore, an incrementing tag scheme is used to ACK interrupts. All MSI supporting chips support TAGGED mode, so the tg3_msi() interrupt handler uses it unconditionally. This invariant is verified when MSI support is tested. Since we can invoke tg3_poll() multiple times per interrupt under high packet load, we fetch a new copy of the tag value in the status block right before we actually do the work. Also, because the tagged status tells the chip exactly which work we have processed, we can make two optimizations: 1) tg3_restart_ints() need not check tg3_has_work() 2) the tg3_timer() need not poke the chip 10 times per second to keep from losing interrupt events Based upon valuable feedback from Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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