From 4d243f92e48a7913938f48fa9ebea5239168bb11 Mon Sep 17 00:00:00 2001 From: David Brownell Date: Fri, 22 Feb 2008 17:28:37 -0800 Subject: atmel_tc clocksource/clockevent code Clocksource and clockevent device based on the Atmel TC blocks. The clockevent device handles both periodic and oneshot modes, so this enables NO_HZ and high res timers on some platforms that previously couldn't use those mechanisms. This works on both AVR32 and AT91 chips, given relevant patches for tclib support (always) and clockevents (or else this will only look like a higher precision clocksource). It's an updated and modularized version of an AT91-only patch that has circulated for some time now. Changes relative to the original patch: * Update to use new tclib API * Replace open-coded do-while loop using goto with a real do-while loop * Minor irq handler optimization: Load register base address from dev_id instead of a global variable. * Aggressively turn off clocks when the clockevent isn't being used * Include the clockevent code on AT91RM9200 as well. The rating is lower than the System Timer, so the clock will usually stay off. * Don't assume that the number of clocks is always equal to the number of irqs. Signed-off-by: David Brownell Signed-off-by: Haavard Skinnemoen --- drivers/misc/Kconfig | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'drivers/misc') diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index b3ba68170b8..4cf928e32e7 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -30,6 +30,31 @@ config ATMEL_TCLIB blocks found on many Atmel processors. This facilitates using these blocks by different drivers despite processor differences. +config ATMEL_TCB_CLKSRC + bool "TC Block Clocksource" + depends on ATMEL_TCLIB && GENERIC_TIME + default y + help + Select this to get a high precision clocksource based on a + TC block with a 5+ MHz base clock rate. Two timer channels + are combined to make a single 32-bit timer. + + When GENERIC_CLOCKEVENTS is defined, the third timer channel + may be used as a clock event device supporting oneshot mode + (delays of up to two seconds) based on the 32 KiHz clock. + +config ATMEL_TCB_CLKSRC_BLOCK + int + depends on ATMEL_TCB_CLKSRC + prompt "TC Block" if ARCH_AT91RM9200 || ARCH_AT91SAM9260 || CPU_AT32AP700X + default 0 + range 0 1 + help + Some chips provide more than one TC block, so you have the + choice of which one to use for the clock framework. The other + TC can be used for other purposes, such as PWM generation and + interval timing. + config IBM_ASM tristate "Device driver for IBM RSA service processor" depends on X86 && PCI && INPUT && EXPERIMENTAL -- cgit v1.2.3