u-boot-brain/drivers
Lukasz Majewski 716662bd19 usb:udc:samsung: Remove redundant cache operation from Samsung UDC driver
A set of cache operations (both invalidation and flush) were redundant
in the S3C HS OTG Samsung driver:

1. s3c_udc_ep0_zlp - to transmit EP0's ZLP packets one don't need to flush
the cache (since it is the zero length transmission)

2. s3c_udc_pre_setup and s3c_ep0_complete_out - cache invalidation is not
needed when the buffer for OUT EP0 transmission is setup, since no data
has yet arrived.

Cache cleanups presented above don't contribute much to transmission speed
up, hence shall be regarded as cosmetic changes.

3. setdma_rx - here the s3c UDC driver's internal buffers were invalidated.
This call is not needed anymore since we reuse the buffers passed from
gadgets. This is a key contribution to transmission speed improvement.

Test condition
- test HW + measurement: Trats - Exynos4210 rev.1
- test HW Trats2 - Exynos4412 rev.1
400 MiB compressed rootfs image download with `thor 0 mmc 0`

Measurements:

Base values (without improvement):
Transmission speed: 9.51 MiB/s

After the change:
Transmission speed: 10.15 MiB/s

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Cc: Marek Vasut <marex@denx.de>
2014-02-06 02:22:45 +01:00
..
bios_emulator drivers: delete unused header files 2014-01-24 16:59:07 -05:00
block sandbox: block driver using host file/device as backing store 2014-01-08 17:24:03 -07:00
bootcount am33xx: Make SoC bootcount driver have its own symbol 2013-11-11 12:17:35 -05:00
crypto drivers: convert makefiles to Kbuild style 2013-10-31 13:26:01 -04:00
ddr/fsl powerpc/mpc85xx: Revise workaround for DDR-A003 2014-01-21 13:40:52 -08:00
dfu dfu: Export allocated dfu buffer size 2013-12-18 19:53:19 +01:00
dma drivers: convert makefiles to Kbuild style 2013-10-31 13:26:01 -04:00
fpga drivers: descend into sub directories only when it is necessary 2013-11-17 14:11:30 -05:00
gpio Merge branch 'u-boot-imx/master' into 'u-boot-arm/master' 2014-01-06 08:49:58 +01:00
hwmon cosmetic: remove empty lines at the top of file 2013-11-08 09:41:37 -05:00
i2c i2c: fti2c010: fix compiler warning on paddr[] 2014-01-13 08:18:38 +01:00
input drivers: convert makefiles to Kbuild style 2013-10-31 13:26:01 -04:00
misc Merge branch 'u-boot-imx/master' into 'u-boot-arm/master' 2014-01-06 08:49:58 +01:00
mmc drivers: delete unused header files 2014-01-24 16:59:07 -05:00
mtd driver/ifc:Change accessor function to take care of endianness 2014-02-03 08:38:51 -08:00
net Merge branch 'net' of git://www.denx.de/git/u-boot-microblaze 2014-02-04 11:51:20 -05:00
pci driver/fsl_pci:Update print to display PCIe generation 2014-02-03 08:38:48 -08:00
pcmcia drivers: convert makefiles to Kbuild style 2013-10-31 13:26:01 -04:00
power fuelgauge: max17042: fix i2c read issue which causes infinity loop. 2014-01-14 09:01:05 -05:00
qe drivers/qe: move the entry to drivers/Makefile 2013-11-17 14:11:31 -05:00
rtc Merge branch 'master' of git://git.denx.de/u-boot-mips 2013-11-11 09:40:34 -05:00
serial serial: uartlite: Reset RX/TX in init 2014-02-04 16:48:57 +01:00
sound drivers: convert makefiles to Kbuild style 2013-10-31 13:26:01 -04:00
spi Merge branch 'master' of git://git.denx.de/u-boot-arm 2014-01-16 13:50:16 -05:00
tpm sandbox: tpm: Fix nvwrite command 2014-01-08 17:26:17 -07:00
twserial drivers: convert makefiles to Kbuild style 2013-10-31 13:26:01 -04:00
usb usb:udc:samsung: Remove redundant cache operation from Samsung UDC driver 2014-02-06 02:22:45 +01:00
video video: ipu reg: Correct reserved array size in struct ipu_idmac 2014-01-12 23:00:06 +01:00
watchdog Merge branch 'iu-boot/master' into 'u-boot-arm/master' 2013-11-09 22:59:47 +01:00
Makefile drivers/qe: move the entry to drivers/Makefile 2013-11-17 14:11:31 -05:00