linux_dsm_epyc7002/drivers
Sarah Sharp c06d68b814 USB: xhci: Minimize HW event ring dequeue pointer writes.
The xHCI specification suggests that writing the hardware event ring dequeue
pointer register too often can be an expensive operation for the xHCI hardware
to manage.  It suggests minimizing the number of writes to that register.

Originally, the driver wrote the event ring dequeue pointer after each
event was processed.  Depending on how the event ring moderation register
is set up and how fast the transfers are completing, there may be several
events processed for each interrupt.  This patch makes the hardware event
ring dequeue pointer be written only once per interrupt.

Make the transfer event handler and port status event handler only write
the software event ring dequeue pointer.  Move the updating of the
hardware event ring dequeue pointer into the interrupt function.  Move the
contents of xhci_set_hc_event_deq() into the interrupt handler.  The
interrupt handler must clear the event handler busy flag, so it might as
well also write the dequeue pointer to the same register.  This eliminates
two 32-bit PCI reads and two 32-bit PCI writes.

Reported-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10 14:35:44 -07:00
..
accessibility
acpi Merge branch 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2010-08-07 17:08:30 -07:00
amba ARM: AMBA: Add pclk support to AMBA bus infrastructure 2010-07-31 13:07:27 +01:00
ata Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq 2010-08-07 12:42:58 -07:00
atm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2010-08-09 21:05:52 -07:00
auxdisplay
base drivers/base/node.c: reduce stack usage of node_read_meminfo() 2010-08-09 20:45:02 -07:00
block Merge branch 'virtio' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus 2010-08-05 13:49:37 -07:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6 2010-08-06 12:25:06 -07:00
cdrom
char Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2010-08-09 21:05:52 -07:00
clocksource x86: Convert common clocksources to use clocksource_register_hz/khz 2010-07-27 12:40:55 +02:00
connector
cpufreq [CPUFREQ] fix brace coding style issue. 2010-08-03 13:47:05 -04:00
cpuidle cpuidle: extend cpuidle and menu governor to handle dynamic states 2010-08-09 20:45:04 -07:00
crypto Merge branch 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6 2010-08-05 15:57:35 -07:00
dca
dio
dma Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx 2010-08-09 21:00:07 -07:00
edac amd64_edac: Minor formatting fix 2010-08-04 11:16:01 +02:00
eisa
firewire Merge firewire branches to be released post v2.6.35 2010-08-02 10:09:04 +02:00
firmware edd: fix possible memory leak in edd_init() error path 2010-08-09 20:45:09 -07:00
gpio Merge branch 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6 2010-08-05 15:57:35 -07:00
gpu drm: fix fallouts from slow-work -> wq conversion 2010-08-09 12:18:44 +02:00
hid Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid 2010-08-04 15:23:49 -07:00
hwmon hwmon: f71882fg: add support for the Fintek F71808E 2010-08-09 20:45:10 -07:00
i2c Merge branch 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6 2010-08-05 15:57:35 -07:00
ide tx493xide: use min_t() macro instead of min() 2010-08-09 03:17:55 -07:00
idle Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq 2010-08-04 11:13:36 -07:00
ieee1394 Merge firewire branches to be released post v2.6.35 2010-08-02 10:09:04 +02:00
ieee802154
infiniband Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband 2010-08-07 17:08:02 -07:00
input Revert "Input: appletouch - fix integer overflow issue" 2010-08-09 13:48:08 +10:00
isdn Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2010-08-09 21:05:52 -07:00
leds leds: Remove owner field from attribute initialization in bd2802 driver 2010-08-05 13:53:35 -07:00
lguest
macintosh Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-08-06 13:25:43 -07:00
mca
md
media Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6 2010-08-07 17:09:24 -07:00
memstick
message Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2010-08-04 15:31:02 -07:00
mfd
misc hmc6352: add driver for the HMC6352 compass 2010-08-09 20:45:10 -07:00
mmc Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6 2010-08-06 12:25:06 -07:00
mtd Merge git://git.infradead.org/mtd-2.6 2010-08-10 11:49:21 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2010-08-09 21:05:52 -07:00
nubus
of of/platform: Register of_platform_drivers with an "of:" prefix 2010-08-01 01:44:18 -06:00
oprofile
parisc Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2010-08-04 15:31:02 -07:00
parport Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6 2010-08-06 12:25:06 -07:00
pci Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx 2010-08-09 21:00:07 -07:00
pcmcia Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6 2010-08-06 12:25:06 -07:00
platform ips driver: make it less chatty 2010-08-03 11:55:15 -04:00
pnp
power POWER: Add JZ4740 battery driver. 2010-08-05 13:26:20 +01:00
pps
ps3
rapidio
regulator regulator: Remove owner field from attribute initialization in regulator core driver 2010-08-05 13:53:35 -07:00
rtc Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus 2010-08-05 08:53:20 -07:00
s390 s390: remove WARN_ON for misc_deregister() failures 2010-08-09 20:45:06 -07:00
sbus Merge branch 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6 2010-08-05 15:57:35 -07:00
scsi Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6 2010-08-06 12:25:06 -07:00
serial Merge branch 'rs485fix' of git://www.jni.nu/cris 2010-08-09 21:04:23 -07:00
sfi
sh
sn
spi of/address: Clean up function declarations 2010-08-01 01:42:42 -06:00
ssb Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6 2010-08-06 12:25:06 -07:00
staging USB: convert usb_hcd bitfields into atomic flags 2010-08-10 14:35:37 -07:00
tc
telephony pcmcia: do not use io_req_t when calling pcmcia_request_io() 2010-08-03 09:04:11 +02:00
thermal
uio uio: Remove IRQF_DISABLED flag from uio_cif.c 2010-08-05 13:53:33 -07:00
usb USB: xhci: Minimize HW event ring dequeue pointer writes. 2010-08-10 14:35:44 -07:00
uwb
vhost Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 2010-08-04 11:47:58 -07:00
video drivers/video/w100fb.c: ignore void return value / fix build failure 2010-08-09 20:44:53 -07:00
virtio
vlynq
w1
watchdog Merge branch 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6 2010-08-05 15:57:35 -07:00
xen Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-08-06 13:25:43 -07:00
zorro
Kconfig
Makefile time: Kill off CONFIG_GENERIC_TIME 2010-07-27 12:40:54 +02:00