From mboxrd@z Thu Jan 1 00:00:00 1970 From: daniel.lezcano@linaro.org (Daniel Lezcano) Date: Sun, 25 Jan 2015 16:03:03 +0100 Subject: [PATCH v3 2/2] clocksource: driver for Conexant Digicolor SoC timer In-Reply-To: <20150125144656.GO2555@sapphire.tkos.co.il> References: <762d81b2cf12922ba28fb58b3ea4d5b7072abefb.1421821466.git.baruch@tkos.co.il> <54C0F30F.9060607@linaro.org> <20150125144656.GO2555@sapphire.tkos.co.il> Message-ID: <54C505A7.6000506@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 01/25/2015 03:46 PM, Baruch Siach wrote: > Hi Daniel, > > On Thu, Jan 22, 2015 at 01:54:39PM +0100, Daniel Lezcano wrote: >> On 01/21/2015 07:36 AM, Baruch Siach wrote: >>> + * Based on: >>> + * Allwinner SoCs hstimer driver >> >> If this is based on the Allwinnner driver, may be you can have a look at the >> patchset sent by Maxim to make sure your implementation is complete ? >> >> https://lkml.org/lkml/2015/1/11/52 > > Thanks for the tip. I'll take the applicable parts from that series. > > [...] > >>> +static void __iomem *timer_base; >>> +static u32 ticks_per_jiffy; >> >> Mind to encapsulate those global variables in a structure and use >> container_of to access those fields like: >> >> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/drivers/clocksource/mtk_timer.c#n56 >> >> ? > > The trouble is that the sched_clock callback (digicolor_timer_sched_read) > needs a static timer_base to find the timer counter. Do you think adding a > structure is worth it only for ticks_per_jiffy? Well you will have to define the global variable for this structure. So you should be able to access the timer base directly. I agree it is not perfect but at least that will encapsulate the code for the clockevents side. >>> +static void digicolor_clkevt_mode(enum clock_event_mode mode, >>> + struct clock_event_device *clk) >>> +{ >>> + switch (mode) { >>> + case CLOCK_EVT_MODE_PERIODIC: >>> + writeb(0, timer_base + CONTROL(TIMER_C)); >> >> Even if that sounds overkill, please replace '0', '1' with whatever macro >> name (eg. TIMER_DISABLE/ENABLE). > > Will do for the entire file. > > [...] > >>> +static struct irqaction digicolor_timer_irq = { >>> + .name = "digicolor_timerC", >>> + .flags = IRQF_TIMER | IRQF_IRQPOLL, >>> + .handler = digicolor_timer_interrupt, >>> + .dev_id = &digicolor_clockevent, >>> +}; >> >> The current trend is to use 'request_irq', so no such structure >> declaration/initialization is needed. > > Thanks. Will do. > >>> + writel(~0, timer_base + COUNT(TIMER_B)); >> >> s/~0/UINT_MAX/ ? > > Ack. > > Thanks for reviewing. I'll post an updated series shortly. Ok, thanks. -- Daniel -- Linaro.org ? Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog