From mboxrd@z Thu Jan 1 00:00:00 1970 From: dinguyen@altera.com (dinguyen at altera.com) Date: Wed, 24 Jul 2013 22:43:17 -0500 Subject: [PATCH 2/2] clocksource: dw_apb_timer_of: Fix read_sched_clock In-Reply-To: <1374723797-22169-1-git-send-email-dinguyen@altera.com> References: <1374723797-22169-1-git-send-email-dinguyen@altera.com> Message-ID: <1374723797-22169-2-git-send-email-dinguyen@altera.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Dinh Nguyen The read_sched_clock should return the ~value because the clock is a countdown implementation. read_sched_clock() should be the same as __apbt_read_clocksource(). If a separate timer for the sched_clock exist, then read_sched_clock() will return an incorrect value. The (sched_io_base + 0x4) needs to be in the function for both cases. Also, remove the use of "dw-apb-timer-sp" and "dw-apb-timer-osc" since they are the same DW clock. Signed-off-by: Dinh Nguyen Acked-by: Jamie Iles CC: Rob Herring CC: Arnd Bergmann Cc: Olof Johansson CC: Jamie Iles Cc: John Stultz Cc: Thomas Gleixner Cc: Linus Walleij Cc: Pavel Machek Cc: Heiko Stuebner Cc: linux-arm-kernel at lists.infradead.org --- drivers/clocksource/dw_apb_timer_of.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/clocksource/dw_apb_timer_of.c b/drivers/clocksource/dw_apb_timer_of.c index 4cbae4f..8e00929 100644 --- a/drivers/clocksource/dw_apb_timer_of.c +++ b/drivers/clocksource/dw_apb_timer_of.c @@ -102,18 +102,17 @@ static void add_clocksource(struct device_node *source_timer) * timer is found. sched_io_base then points to the current_value * register of the clocksource timer. */ - sched_io_base = iobase + 0x04; + sched_io_base = iobase; sched_rate = rate; } static u32 read_sched_clock(void) { - return __raw_readl(sched_io_base); + return ~__raw_readl(sched_io_base + 0x4); } static const struct of_device_id sptimer_ids[] __initconst = { { .compatible = "picochip,pc3x2-rtc" }, - { .compatible = "snps,dw-apb-timer-sp" }, { /* Sentinel */ }, }; @@ -153,4 +152,4 @@ static void __init dw_apb_timer_init(struct device_node *timer) num_called++; } CLOCKSOURCE_OF_DECLARE(pc3x2_timer, "picochip,pc3x2-timer", dw_apb_timer_init); -CLOCKSOURCE_OF_DECLARE(apb_timer, "snps,dw-apb-timer-osc", dw_apb_timer_init); +CLOCKSOURCE_OF_DECLARE(apb_timer, "snps,dw-apb-timer", dw_apb_timer_init); -- 1.7.9.5