kernel/drivers/clocksource/dw_apb_timer_of.c, branch linux-5.1.y

clocksource/drivers/dw_apb: Add reset control

2018-10-07T12:16:35Z

Add code to retrieve the reset property from the dw-apb timers and if the property is available, the safe operation is to assert the timer into reset, and followed by a deassert of the timer reset (brings the timer out of reset). This patch is needed for systems where the bootloader has left the timer not used in reset. - Trivial conflict with commit a74bd1ad7a: "Convert to using %pOFn instead of device_node.name" Reported-by: Marek Vasut Signed-off-by: Dinh Nguyen Signed-off-by: Daniel Lezcano

clocksource: Convert to using %pOFn instead of device_node.name

2018-10-03T12:36:52Z

In preparation to remove the node name pointer from struct device_node, convert printf users to use the %pOFn format specifier. Cc: Daniel Lezcano Cc: Thomas Gleixner Cc: Michal Simek Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Rob Herring Signed-off-by: Daniel Lezcano

clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE

2017-06-14T09:58:45Z

The CLOCKSOURCE_OF_DECLARE macro is used widely for the timers to declare the clocksource at early stage. However, this macro is also used to initialize the clockevent if any, or the clockevent only. It was originally suggested to declare another macro to initialize a clockevent, so in order to separate the two entities even they belong to the same IP. This was not accepted because of the impact on the DT where splitting a clocksource/clockevent definition does not make sense as it is a Linux concept not a hardware description. On the other side, the clocksource has not interrupt declared while the clockevent has, so it is easy from the driver to know if the description is for a clockevent or a clocksource, IOW it could be implemented at the driver level. So instead of dealing with a named clocksource macro, let's use a more generic one: TIMER_OF_DECLARE. The patch has not functional changes. Signed-off-by: Daniel Lezcano Acked-by: Heiko Stuebner Acked-by: Neil Armstrong Acked-by: Arnd Bergmann Acked-by: Matthias Brugger Reviewed-by: Linus Walleij

clocksources: Switch back to the clksrc table

2016-06-28T08:19:35Z

All the clocksource drivers's init function are now converted to return an error code. CLOCKSOURCE_OF_DECLARE is no longer used as well as the clksrc-of table. Let's convert back the names: - CLOCKSOURCE_OF_DECLARE_RET => CLOCKSOURCE_OF_DECLARE - clksrc-of-ret => clksrc-of Signed-off-by: Daniel Lezcano For exynos_mct and samsung_pwm_timer: Acked-by: Krzysztof Kozlowski For arch/arc: Acked-by: Vineet Gupta For mediatek driver: Acked-by: Matthias Brugger For the Rockchip-part Acked-by: Heiko Stuebner For STi : Acked-by: Patrice Chotard For the mps2-timer.c and versatile.c changes: Acked-by: Liviu Dudau For the OXNAS part : Acked-by: Neil Armstrong For LPC32xx driver: Acked-by: Sylvain Lemieux For Broadcom Kona timer change: Acked-by: Ray Jui For Sun4i and Sun5i: Acked-by: Chen-Yu Tsai For Meson6: Acked-by: Carlo Caione For Keystone: Acked-by: Santosh Shilimkar For NPS: Acked-by: Noam Camus For bcm2835: Acked-by: Eric Anholt

clocksource/drivers/dw_apb_timer: Convert init function to return error

2016-06-28T08:19:19Z

The init functions do not return any error. They behave as the following: - panic, thus leading to a kernel crash while another timer may work and make the system boot up correctly or - print an error and let the caller unaware if the state of the system Change that by converting the init functions to return an error conforming to the CLOCKSOURCE_OF_RET prototype. Proper error handling (rollback, errno value) will be changed later case by case, thus this change just return back an error or success in the init function. Signed-off-by: Daniel Lezcano

clocksource/drivers/dw_apb_timer_of: Implement ARM delay timer

2015-12-15T08:42:00Z

Implement an ARM delay timer to be used for udelay(). This allows us to skip the delay loop calibration at boot on Marvell BG2, BG2Q, BG2CD platforms. And after this patch, udelay() will be unaffected by CPU frequency changes. Note: Although in case there are several possible delay timers, we may not select the "best" delay timer. Take one Marvell Berlin platform for example: we have arch timer and dw-apb timer. The arch timer freq is 25MHZ while the dw-apb timer freq is 100MHZ, current selection would choose the dw-apb timer. But the dw apb timer is on the APB bus while arch timer sits in CPU, the cost of accessing the apb timer is higher than the arch timer. We could introduce "rating" concept to delay timer, but this approach "brings a lot of complexity and workarounds in the code for a small benefit" as pointed out by Daniel. Later, Arnd pointed out "However, we could argue that this actually doesn't matter at all, because the entire point of the ndelay()/ udelay()/mdelay() functions is to waste CPU cycles doing not much at all, so we can just as well waste them reading the timer register than spinning on the CPU reading the arch timer more often.", so we just simply register the dw apb base delay timer. Signed-off-by: Jisheng Zhang Signed-off-by: Daniel Lezcano

clocksource/drivers/dw_apb_timers_of: Fix IO endianness causing time jumps

2015-03-31T07:15:57Z

The dw_apb_timer_of timer is using __raw_readl() to access the timer register, which is causing issues when the system is running in big endian mode. Fix this by using readl_relaxed() which should account for the endian settings. This fixes issues where the time jumps around in the dmesg output due to returnling __le32 values. For an example, these two console lines show time running backwards: [ 49.882572] CPU1: failed to come online [ 43.282457] Brought up 1 CPUs Signed-off-by: Ben Dooks Signed-off-by: Daniel Lezcano Acked-by: Nicolas Ferre Cc: Dinh Nguyen Cc: Linux ARM Kernel Cc: Thomas Gleixner Cc: digetx@gmail.com Cc: hdegoede@redhat.com Cc: laurent.pinchart+renesas@ideasonboard.com Cc: maxime.ripard@free-electrons.com Cc: viresh.kumar@linaro.org Link: http://lkml.kernel.org/r/1427746633-9137-10-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar

clocksource: dw_apb_timer_of: Do not trace read_sched_clock

2014-05-23T07:23:09Z

We do not need to trace read_sched_clock function, so add notrace attribute for this function. Signed-off-by: Yang Wei Signed-off-by: Daniel Lezcano

clocksource: dw_apb_timer_of: Fix support for dts binding "snps,dw-apb-timer"

2013-12-10T18:49:18Z

In commit 620f5e1cbf (dts: Rename DW APB timer compatible strings), both "snps,dw-apb-timer-sp" and "snps,dw-apb-timer-osc" were deprecated in place of "snps,dw-apb-timer". But the driver also needs to be udpated in order to support this new binding "snps,dw-apb-timer". Signed-off-by: Dinh Nguyen Signed-off-by: Daniel Lezcano

clocksource: dw_apb_timer_of: Fix read_sched_clock

2013-12-10T18:49:18Z

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(). Signed-off-by: Dinh Nguyen Signed-off-by: Daniel Lezcano