CVS commit: src/sys/arch/arm/amlogic

["Jared D. McNeill" <jmcneill%netbsd.org@localhost>]

Module Name:    src
Committed By:   jmcneill
Date:           Sun Apr 19 21:23:01 UTC 2015

Modified Files:
        src/sys/arch/arm/amlogic: amlogic_sdhc.c

Log Message:
The Amlogic SDHC controller doesn't support SG DMA. When we advertise
DMA but not SG DMA support, the sdmmc layer breaks up transfers into
multiple PAGE_SIZE (8KB here) transfers.

Remove the DMA capability flag and do transfers through a MAXPHYS-sized
buffer instead. This lets us do larger transfers and even with the memcpy,
still a significant win for performance.

Before: 134217728 bytes transferred in 15.301 secs (8771827 bytes/sec)
After:  134217728 bytes transferred in 8.834 secs (15193313 bytes/sec)


To generate a diff of this commit:
cvs rdiff -u -r1.4 -r1.5 src/sys/arch/arm/amlogic/amlogic_sdhc.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.