f248076c0d
Add a function omap2_gp_clockevent_set_gptimer() for board-*.c files to use in .init_irq functions to configure the system tick GPTIMER. Practical choices at this point are GPTIMER1 or GPTIMER12. Both of these timers are in the WKUP powerdomain, and so are unaffected by chip power management. GPTIMER1 can use sys_clk as a source, for applications where a high-resolution timer is more important than power management. GPTIMER12 has the special property that it has the secure 32kHz oscillator as its source clock, which may be less prone to glitches than the off-chip 32kHz oscillator. But on HS devices, it may not be available for Linux use. It appears that most boards are fine with GPTIMER1, but BeagleBoard should use GPTIMER12 when using a 32KiHz timer source, due to hardware bugs in revisions B4 and below. Modify board-omap3beagle.c to use GPTIMER12. This patch originally used a Kbuild config option to select the GPTIMER, but was changed to allow this to be specified in board-*.c files, per Tony's request. Kalle Vallo <kalle.valo@nokia.com> found a bug in an earlier version of this patch - thanks Kalle. Tested on Beagle rev B4 ES2.1, with and without CONFIG_OMAP_32K_TIMER, and 3430SDP. Signed-off-by: Paul Walmsley <paul@pwsan.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Cc: Kalle Valo <kalle.valo@nokia.com> |
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| alpha | ||
| arm | ||
| avr32 | ||
| blackfin | ||
| cris | ||
| frv | ||
| h8300 | ||
| ia64 | ||
| m32r | ||
| m68k | ||
| m68knommu | ||
| mips | ||
| mn10300 | ||
| parisc | ||
| powerpc | ||
| s390 | ||
| sh | ||
| sparc | ||
| um | ||
| x86 | ||
| xtensa | ||
| .gitignore | ||
| Kconfig | ||