| commit | 9dabb3f3269d042908bf1f4e685413c39cc8c373 | |
| author | Guennadi Liakhovetski <g.liakhovetski@gmx.de> | |
| Fri, 21 Jan 2011 15:56:42 +0000 (21 16:56 +0100) | ||
| committer | Grant Likely <grant.likely@secretlab.ca> | |
| Fri, 21 Jan 2011 17:02:35 +0000 (21 10:02 -0700) | ||
| tree | a6913470397af37729670966b9683aec48edb525 | treesnapshot (tar.gz zip) |
| parent | e2dbf5ebcc983b0349ab507bf7dd5562cf88dd24 | commitdiff |
spi/spi_sh_msiof: consolidate data in 8-bit mode into 32-bit words
Instead of sending data 8 bits at a time in 8-bit SPI mode, swap bytes
and send and receive them 32 bits at a time. Tested with an SD-card,
with which this patch reduced the number of interrupts by 50%, when
reading 5MiB of data (there are also small service packets, the number
of interrupts, produced by 512-byte sectors should, of course, drop by
75%), and improved throughput by more than 40%.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Instead of sending data 8 bits at a time in 8-bit SPI mode, swap bytes
and send and receive them 32 bits at a time. Tested with an SD-card,
with which this patch reduced the number of interrupts by 50%, when
reading 5MiB of data (there are also small service packets, the number
of interrupts, produced by 512-byte sectors should, of course, drop by
75%), and improved throughput by more than 40%.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
| drivers/spi/spi_sh_msiof.c | diffblobblamehistory |