]> git.karo-electronics.de Git - karo-tx-linux.git/commit
ARM: OMAP: DMTimer: Use posted mode
authorRichard Woodruff <r-woodruff2@ti.com>
Thu, 3 Jul 2008 09:24:30 +0000 (12:24 +0300)
committerTony Lindgren <tony@atomide.com>
Thu, 3 Jul 2008 09:24:30 +0000 (12:24 +0300)
commit0f0d0807093d2d72ee772a1b4ba1d0b088a79a2b
tree2f9708998b5102e0ac6cdc1cd98d6f71f67954c6
parent4621d588e0e8b5b11cd913fe706e35915c1b83a3
ARM: OMAP: DMTimer: Use posted mode

This patch adds the use of write posting for the timer.  Previously, every
write could lock the requestor for almost 3x32KHz cycles.  This patch only
synchronizes before writes and reads instead of after them and it does
it on per register basis.  Doing it this way there is some chance to hide
some of the sync latency.  It also removes some needless reads when
non-posted mode is there.  With out this fix the read/writes take almost
2% CPU load @500MHz just waiting on tick timer registers.

Also define new 34xx only registers.

Signed-off-by: Richard Woodruff <r-woodruff2@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
arch/arm/plat-omap/dmtimer.c