From 11b10341bd12c87a8409c69cdcd7ee898400842f Mon Sep 17 00:00:00 2001 From: Benoit Cousson Date: Sun, 10 Jul 2011 05:56:30 -0600 Subject: OMAP: hwmod: Wait the idle status to be disabled It is mandatory to wait for a module to be in disabled state before potentially disabling source clock or re-asserting a reset. omap_hwmod_idle and omap_hwmod_shutdown does not wait for the module to be fully idle. Add a cm_xxx accessor to wait the clkctrl idle status to be disabled. Fix hwmod_[idle|shutdown] to use this API. Based on Rajendra's initial patch. Please note that most interconnects hwmod will return one timeout because it is impossible for them to be in idle since the processor is accessing the registers though the interconnect. Signed-off-by: Benoit Cousson Signed-off-by: Rajendra Nayak Cc: Paul Walmsley Cc: Todd Poynor [paul@pwsan.com: move cpu_is_*() tests to the top of _wait_target_disable(); incorporate some feedback from Todd] Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/cminst44xx.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'arch/arm/mach-omap2/cminst44xx.c') diff --git a/arch/arm/mach-omap2/cminst44xx.c b/arch/arm/mach-omap2/cminst44xx.c index 9033dd4937c1..0fe3f147f262 100644 --- a/arch/arm/mach-omap2/cminst44xx.c +++ b/arch/arm/mach-omap2/cminst44xx.c @@ -284,3 +284,28 @@ int omap4_cminst_wait_module_ready(u8 part, u16 inst, s16 cdoffs, return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY; } +/** + * omap4_cminst_wait_module_idle - wait for a module to be in 'disabled' + * state + * @part: PRCM partition ID that the CM_CLKCTRL register exists in + * @inst: CM instance register offset (*_INST macro) + * @cdoffs: Clockdomain register offset (*_CDOFFS macro) + * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro) + * + * Wait for the module IDLEST to be disabled. Some PRCM transition, + * like reset assertion or parent clock de-activation must wait the + * module to be fully disabled. + */ +int omap4_cminst_wait_module_idle(u8 part, u16 inst, s16 cdoffs, u16 clkctrl_offs) +{ + int i = 0; + + if (!clkctrl_offs) + return 0; + + omap_test_timeout((_clkctrl_idlest(part, inst, cdoffs, clkctrl_offs) == + CLKCTRL_IDLEST_DISABLED), + MAX_MODULE_READY_TIME, i); + + return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY; +} -- cgit v1.2.3