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path: root/drivers/net/wan/ixp4xx_hss.c (follow)
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2009-09-07IXP42x HSS support for setting internal clock rateKrzysztof Halasa1-4/+91
HSS usually uses external clocks, so it's not a big deal. Internal clock is used for direct DTE-DTE connections and when the DCE doesn't provide it's own clock. This also depends on the oscillator frequency. Intel seems to have calculated the clock register settings for 33.33 MHz (66.66 MHz timer base). Their settings seem quite suboptimal both in terms of average frequency (60 ppm is unacceptable for G.703 applications, their primary intended usage(?)) and jitter. Many (most?) platforms use a 33.333 MHz oscillator, a 10 ppm difference from Intel's base. Instead of creating static tables, I've created a procedure to program the HSS clock register. The register consists of 3 parts (A, B, C). The average frequency (= bit rate) is: 66.66x MHz / (A + (B + 1) / (C + 1)) The procedure aims at the closest average frequency, possibly at the cost of increased jitter. Nobody would be able to directly drive an unbufferred transmitter with a HSS anyway, and the frequency error is what it really counts. I've verified the above with an oscilloscope on IXP425. It seems IXP46x and possibly IXP43x use a bit different clock generation algorithm - it looks like the avg frequency is: (on IXP465) 66.66x MHz / (A + B / (C + 1)). Also they use much greater precomputed A and B - on IXP425 it would simply result in more jitter, but I don't know how does it work on IXP46x (perhaps 3 least significant bits aren't used?). Anyway it looks that they were aiming for exactly +60 ppm or -60 ppm, while <1 ppm is typically possible (with a synchronized clock, of course). The attached patch makes it possible to set almost any bit rate (my IXP425 533 MHz quits at > 22 Mb/s if a single port is used, and the minimum is ca. 65 Kb/s). This is independent of MVIP (multi-E1/T1 on one HSS) mode. Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-15Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6David S. Miller1-5/+6
Conflicts: Documentation/feature-removal-schedule.txt drivers/scsi/fcoe/fcoe.c net/core/drop_monitor.c net/core/net-traces.c
2009-05-29net: replace dma_sync_single with dma_sync_single_for_cpuFUJITA Tomonori1-2/+2
This replaces dma_sync_single() with dma_sync_single_for_cpu() because dma_sync_single() is an obsolete API; include/linux/dma-mapping.h says: /* Backwards compat, remove in 2.7.x */ #define dma_sync_single dma_sync_single_for_cpu #define dma_sync_sg dma_sync_sg_for_cpu Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-25IXP4xx: Change QMgr function names to qmgr_stat_*_watermark and clean the comments.Krzysztof Hałasa1-5/+4
Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
2009-05-23IXP4xx: Ethernet and WAN drivers now support "high" hardware queues.Krzysztof Hałasa1-4/+6
Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
2009-05-09IXP4xx: use "ENODEV" instead of "ENOSYS" in module initialization.Krzysztof Hałasa1-2/+2
ENOSYS makes modutils complain about missing kernel module support. Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
2009-01-21net: Remove redundant NAPI functionsBen Hutchings1-6/+6
Following the removal of the unused struct net_device * parameter from the NAPI functions named *netif_rx_* in commit 908a7a1, they are exactly equivalent to the corresponding *napi_* functions and are therefore redundant. Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-21WAN: Convert generic HDLC drivers to netdev_ops.Krzysztof Hałasa1-3/+9
Also remove unneeded last_rx update from Synclink drivers. Synclink part mostly by Stephen Hemminger. Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-12WAN: Fix NAPI interface in IXP4xx HSS driver.Krzysztof Hałasa1-3/+3
Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-29net: Fix more NAPI interface netdev argument drop fallout.Kamalesh Babulal1-1/+1
I hit similar build failure due to the change in the netif_rx_reschedule() drivers/net/ehea/ehea_main.c: In function 'ehea_poll': drivers/net/ehea/ehea_main.c:844: warning: passing argument 1 of 'netif_rx_reschedule' from incompatible pointer type drivers/net/ehea/ehea_main.c:844: error: too many arguments to function 'netif_rx_reschedule' make[3]: *** [drivers/net/ehea/ehea_main.o] Error 1 greping through the sources for the changes missed out, we have ./drivers/net/arm/ixp4xx_eth.c:507: netif_rx_reschedule(dev, napi)) { ./drivers/net/arm/ep93xx_eth.c:310: if (more && netif_rx_reschedule(dev, napi)) ./drivers/net/wan/ixp4xx_hss.c:657: netif_rx_reschedule(dev, napi)) { Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-22IXP4xx: move common debugging from network drivers to QMGR module.Krzysztof Hałasa1-43/+11
Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
2008-12-22WAN: Add IXP4xx HSS HDLC driver.Krzysztof Hałasa1-0/+1357
Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>