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path: root/drivers/net/spider_net.h
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2007-10-10[NET]: Make NAPI polling independent of struct net_device objects.Stephen Hemminger
Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-08spidernet: Replace literal with constLinas Vepstas
Replace literal with const; add bit definitions. Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-07-08spidernet: fix misnamed flagLinas Vepstas
The transmit frame tail bit is stranglely misnamed as "no checksum". Fix the name to what it should be: "transmit frame tail". No functional change, just a name change. Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20spidernet: turn off descriptor chain end interrupt.Linas Vepstas
At some point, the transmit descriptor chain end interrupt (TXDCEINT) was turned on. This is a mistake; and it damages small packet transmit performance, as it results in a huge storm of interrupts. Turn it off. Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20spidernet: silence the ramfull messagesLinas Vepstas
Although the previous patch resolved issues with hangs when the RX ram full interrupt is encountered, there are still situations where lots of RX ramfull interrupts arrive, resulting in a noisy log in syslog. There is no need for this. Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20spidernet: Cure RX ram full bugLinas Vepstas
This patch fixes a rare deadlock that can occur when the kernel is not able to empty out the RX ring quickly enough. Below follows a detailed description of the bug and the fix. As long as the OS can empty out the RX buffers at a rate faster than the hardware can fill them, there is no problem. If, for some reason, the OS fails to empty the RX ring fast enough, the hardware GDACTDPA pointer will catch up to the head, notice the not-empty condition, ad stop. However, RX packets may still continue arriving on the wire. The spidernet chip can save some limited number of these in local RAM. When this local ram fills up, the spider chip will issue an interrupt indicating this (GHIINT0STS will show ERRINT, and the GRMFLLINT bit will be set in GHIINT1STS). When te RX ram full condition occurs, a certain bug/feature is triggered that has to be specially handled. This section describes the special handling for this condition. When the OS finally has a chance to run, it will empty out the RX ring. In particular, it will clear the descriptor on which the hardware had stopped. However, once the hardware has decided that a certain descriptor is invalid, it will not restart at that descriptor; instead it will restart at the next descr. This potentially will lead to a deadlock condition, as the tail pointer will be pointing at this descr, which, from the OS point of view, is empty; the OS will be waiting for this descr to be filled. However, the hardware has skipped this descr, and is filling the next descrs. Since the OS doesn't see this, there is a potential deadlock, with the OS waiting for one descr to fill, while the hardware is waiting for a differen set of descrs to become empty. A call to show_rx_chain() at this point indicates the nature of the problem. A typical print when the network is hung shows the following: net eth1: Spider RX RAM full, incoming packets might be discarded! net eth1: Total number of descrs=256 net eth1: Chain tail located at descr=255 net eth1: Chain head is at 255 net eth1: HW curr desc (GDACTDPA) is at 0 net eth1: Have 1 descrs with stat=xa0800000 net eth1: HW next desc (GDACNEXTDA) is at 1 net eth1: Have 127 descrs with stat=x40800101 net eth1: Have 1 descrs with stat=x40800001 net eth1: Have 126 descrs with stat=x40800101 net eth1: Last 1 descrs with stat=xa0800000 Both the tail and head pointers are pointing at descr 255, which is marked xa... which is "empty". Thus, from the OS point of view, there is nothing to be done. In particular, there is the implicit assumption that everything in front of the "empty" descr must surely also be empty, as explained in the last section. The OS is waiting for descr 255 to become non-empty, which, in this case, will never happen. The HW pointer is at descr 0. This descr is marked 0x4.. or "full". Since its already full, the hardware can do nothing more, and thus has halted processing. Notice that descrs 0 through 254 are all marked "full", while descr 254 and 255 are empty. (The "Last 1 descrs" is descr 254, since tail was at 255.) Thus, the system is deadlocked, and there can be no forward progress; the OS thinks there's nothing to do, and the hardware has nowhere to put incoming data. This bug/feature is worked around with the spider_net_resync_head_ptr() routine. When the driver receives RX interrupts, but an examination of the RX chain seems to show it is empty, then it is probable that the hardware has skipped a descr or two (sometimes dozens under heavy network conditions). The spider_net_resync_head_ptr() subroutine will search the ring for the next full descr, and the driver will resume operations there. Since this will leave "holes" in the ring, there is also a spider_net_resync_tail_ptr() that will skip over such holes. Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-27spidernet: janitorial, typosLinas Vepstas
Janitorial patch. Undo long lines, fix typo in err msg. Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Cc: Jens Osterkamp <Jens.Osterkamp@de.ibm.com> Cc: Kou Ishizaki <kou.ishizaki@toshiba.co.jp> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-27spidernet: separate hardware state from driver state.Linas Vepstas
This patch separates the hardware descriptor state from the driver descriptor state, per (old) suggestion from Ben Herrenschmidt. This compiles and boots and seems to work. Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Cc: Jens Osterkamp <Jens.Osterkamp@de.ibm.com> Cc: Kou Ishizaki <kou.ishizaki@toshiba.co.jp> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-27spidernet: move medium variable into card structJens Osterkamp
This moves the medium variable into the spidernet card structure. It renames the GMII_ variables to BCM54XX specific ones. Signed-off-by: Jens Osterkamp <jens@de.ibm.com> Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-27spidernet: spidernet: add support for CellebKou Ishizaki
This patch adds or changes some HW specific settings for spider_net on Celleb. Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp> Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-27spidernet: autoneg support for CellebKou Ishizaki
Add auto negotiation support for Celleb. Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp> Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-05Spidernet remove rxramfull taskletLinas Vepstas
Get rid of the rxramfull tasklet, and let the NAPI poll routine deal with this situation. (The rxramfull interrupt is simply stating that the h/w has run out of room for incoming packets). Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Cc: James K Lewis <jklewis@us.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-05Spidernet add net_ratelimit to suppress long outputLinas Vepstas
This patch adds net_ratelimit to many of the printks in order to limit extraneous warning messages (created in response to Bug 28554). This patch supercedes all previous ratelimit patches. This has been tested, please apply. From: James K Lewis <jklewis@us.ibm.com> Signed-off-by: James K Lewis <jklewis@us.ibm.com> Signed-off-by: Linas Vepstas <jlinas@austin.ibm.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-05Spidernet DMA coalescingLinas Vepstas
The current driver code performs 512 DMA mappings of a bunch of 32-byte ring descriptor structures. This is silly, as they are all in contiguous memory. This patch changes the code to dma_map_coherent() each rx/tx ring as a whole. Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Cc: James K Lewis <jklewis@us.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-11-30[PATCH] spidernet: poor network performanceLinas Vepstas
Correct a problem seen on later kernels running the NetPIPE application. Specifically, NetPIPE would begin running very slowly at the 1533 packet size. It was determined that Spidernet slowed with an idle DMA engine. Signed-off-by: James K Lewis <jklewis@us.ibm.com> Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-11-30[PATCH] Spidernet: remove ETH_ZLEN check in earlier patchJames K Lewis
In an earlier patch, code was added to pad packets that were less that ETH_ZLEN (60) bytes using the skb_pad function. This has caused hangs when accessing certain NFS mounted file systems. This patch removes the check and solves the NFS problem. The driver, with this patch, has been tested extensively. Please apply. Signed-off-by: James K Lewis <jklewis@us.ibm.com> Cc: Stephen Hemminger <shemminger@osdl.org> Cc: Jeff Garzik <jgarzik@pobox.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-10-11[PATCH] powerpc/cell spidernet variable name changeLinas Vepstas
Cosmetic patch: give the variable holding the numer of descriptors a more descriptive name, so to avoid confusion. Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Cc: James K Lewis <jklewis@us.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-10-11[PATCH] powerpc/cell spidernet low watermark patch.Linas Vepstas
Implement basic low-watermark support for the transmit queue. Hardware low-watermarks allow a properly configured kernel to continously stream data to a device and not have to handle any interrupts at all in doing so. Correct zero-interrupt operation can be actually observed for this driver, when the socket buffer is made large enough. The basic idea of a low-watermark interrupt is as follows. The device driver queues up a bunch of packets for the hardware to transmit, and then kicks the hardware to get it started. As the hardware drains the queue of pending, untransmitted packets, the device driver will want to know when the queue is almost empty, so that it can queue some more packets. If the queue drains down to the low waterark, then an interrupt will be generated. However, if the kernel/driver continues to add enough packets to keep the queue partially filled, no interrupt will actually be generated, and the hardware can continue streaming packets indefinitely in this mode. The impelmentation is done by setting the DESCR_TXDESFLG flag in one of the packets. When the hardware sees this flag, it will interrupt the device driver. Because this flag is on a fixed packet, rather than at fixed location in the queue, the code below needs to move the flag as more packets are queued up. This implementation attempts to keep the flag at about 1/4 from "empty". Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: James K Lewis <jklewis@us.ibm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-10-11[PATCH] powerpc/cell spidernet bogus rx interrupt bitLinas Vepstas
The current receive interrupt mask sets a bogus bit that doesn't even belong to the definition of this register. Remove it. Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Cc: James K Lewis <jklewis@us.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-10-11[PATCH] Spidernet fix register field definitionsLinas Vepstas
This patch fixes the names of a few fields in the DMA control register. There is no functional change. Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Cc: James K Lewis <jklewis@us.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-10-11[PATCH] powerpc/cell spidernet burst alignment patch.Linas Vepstas
This patch increases the Burst Address alignment from 64 to 1024 in the Spidernet driver. This improves transmit performance for large packets. From: James K Lewis <jklewis@us.ibm.com> Signed-off-by: James K Lewis <jklewis@us.ibm.com> Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-10-11[PATCH] powerpc/cell spidernet ethtool -i version number info.Linas Vepstas
This patch adds version information as reported by ethtool -i to the Spidernet driver. From: James K Lewis <jklewis@us.ibm.com> Signed-off-by: James K Lewis <jklewis@us.ibm.com> Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-09-22[PATCH] Spidernet: add ethtool -S (show statistics)Jim Lewis
Add the ethtool -S (show statistics) feature to the Spidernet ethernet driver. I have tested it extensively and believe it is ready to be applied. Signed-off-by: James K Lewis <jklewis@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-09-13drivers/net: const-ify ethtool_ops declarationsJeff Garzik
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-08-19[PATCH] Add ethtool -g support to Spidernet network driverJim Lewis
Add ethtool -g (show ring sizes) support to the Spidernet network driver. Signed-off-by: James K Lewis <jklewis@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-07-17[PATCH] spidernet: rework tx queue handlingJens Osterkamp
With this patch TX queue descriptors are not chained per default any more. The pointer to next descriptor is set only when next descriptor is prepaired for transfer. Also the mechanism of checking wether Spider is ready has been changed: it checks not for CARDOWNED flag in status of previous descriptor but for a TXDMAENABLED flag in Spider's register. Signed-off-by: Maxim Shchetynin <maxim@de.ibm.com> Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Signed-off-by: Jens Osterkamp <Jens.Osterkamp@de.ibm.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-05-08spidernet: introduce new settingJens Osterkamp
We found a new chip setting that we need in order to make the driver work more reliable. Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
2006-01-17[PATCH] spidernet: performance optimizationsArnd Bergmann
Performance optimizations, changes in these areas: - RX and TX checksum offload - correct maximum MTU - don't use TX interrupts anymore, use a timer instead - remove some superfluous barriers - improve RX RAM full handling From: Utz Bacher <utz.bacher@de.ibm.com> Signed-off-by: Jens Osterkamp <jens.osterkamp@de.ibm.com> Signed-off-by: Arnd Bergmann <arndb@de.ibm.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2006-01-17[PATCH] spidernet: fix HW structures for 64 bit dma_addr_tArnd Bergmann
The driver incorrectly used dma_addr_t to describe HW structures and consequently broke when that type was changed in 2.6.15-rc. This changed spidernet to use u32 for 32 bit HW defined structure elements. From: Jens Osterkamp <Jens.Osterkamp@de.ibm.com> Signed-off-by: Jens Osterkamp <Jens.Osterkamp@de.ibm.com> Signed-off-by: Arnd Bergmann <arndb@de.ibm.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2005-09-06[PATCH] net: add driver for the NIC on Cell BladesJens Osterkamp
This patch adds a driver for a new 1000 Mbit ethernet NIC. It is integrated on the south bridge that is used for our Cell Blades. The code gets the MAC address from the Open Firmware device tree, so it won't compile on platforms other than ppc64. This is the first public release, so I don't expect the first version to get merged, but I'd aim for integration within the 2.6.13 time frame. Cc: Utz Bacher <utz.bacher@de.ibm.com> Signed-off-by: Arnd Bergmann <arndb@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>