On Sun, Oct 23, 2016 at 03:12:28PM +0300, Noam Camus wrote: > From: Noam Camus <noamca@xxxxxxxxxxxx> > > Till now we used clockevent from generic ARC driver. > This was enough as long as we worked with simple multicore SoC. > When we are working with multithread SoC each HW thread can be > scheduled to receive timer interrupt using timer mask register. > This patch will provide a way to control clock events per HW thread. > > The design idea is that for each core there is dedicated regirtser > (TSI) serving all 16 HW threads. > The register is a bitmask with one bit for each HW thread. > When HW thread wants that next expiration of timer interrupt will > hit it then the proper bit should be set in this dedicated register. > When timer expires all HW threads within this core which their bit > is set at the TSI register will be interrupted. > > Driver can be used from device tree by: > compatible = "ezchip,nps400-timer0" <-- for clocksource > compatible = "ezchip,nps400-timer1" <-- for clockevent > > Note that name convention for timer0/timer1 was taken from legacy > ARC design. This design is our base before adding HW threads. > > Signed-off-by: Noam Camus <noamca@xxxxxxxxxxxx> > > Change-Id: Ib351e6fc7a6b691293040ae655f202f3cc2c1298 > --- > .../bindings/timer/ezchip,nps400-timer.txt | 15 -- > .../bindings/timer/ezchip,nps400-timer0.txt | 17 ++ > .../bindings/timer/ezchip,nps400-timer1.txt | 15 ++ For the binding, Acked-by: Rob Herring <robh@xxxxxxxxxx> However, one issue below... > drivers/clocksource/timer-nps.c | 220 +++++++++++++++++++- > include/linux/cpuhotplug.h | 1 + > 5 files changed, 248 insertions(+), 20 deletions(-) > delete mode 100644 Documentation/devicetree/bindings/timer/ezchip,nps400-timer.txt > create mode 100644 Documentation/devicetree/bindings/timer/ezchip,nps400-timer0.txt > create mode 100644 Documentation/devicetree/bindings/timer/ezchip,nps400-timer1.txt > diff --git a/drivers/clocksource/timer-nps.c b/drivers/clocksource/timer-nps.c > index 6156e54..0757328 100644 > --- a/drivers/clocksource/timer-nps.c > +++ b/drivers/clocksource/timer-nps.c > @@ -46,7 +46,7 @@ > /* This array is per cluster of CPUs (Each NPS400 cluster got 256 CPUs) */ > static void *nps_msu_reg_low_addr[NPS_CLUSTER_NUM] __read_mostly; > > -static unsigned long nps_timer_rate; > +static unsigned long nps_timer1_freq; > static int nps_get_timer_clk(struct device_node *node, > unsigned long *timer_freq, > struct clk *clk) > @@ -87,10 +87,10 @@ static int __init nps_setup_clocksource(struct device_node *node) > nps_host_reg((cluster << NPS_CLUSTER_OFFSET), > NPS_MSU_BLKID, NPS_MSU_TICK_LOW); > > - nps_get_timer_clk(node, &nps_timer_rate, clk); > + nps_get_timer_clk(node, &nps_timer1_freq, clk); > > - ret = clocksource_mmio_init(nps_msu_reg_low_addr, "EZnps-tick", > - nps_timer_rate, 301, 32, nps_clksrc_read); > + ret = clocksource_mmio_init(nps_msu_reg_low_addr, "nps-tick", > + nps_timer1_freq, 301, 32, nps_clksrc_read); > if (ret) { > pr_err("Couldn't register clock source.\n"); > clk_disable_unprepare(clk); > @@ -99,5 +99,215 @@ static int __init nps_setup_clocksource(struct device_node *node) > return ret; > } > > -CLOCKSOURCE_OF_DECLARE(ezchip_nps400_clksrc, "ezchip,nps400-timer", > +CLOCKSOURCE_OF_DECLARE(ezchip_nps400_clksrc, "ezchip,nps400-timer1", > nps_setup_clocksource); You should keep the old string here for backwards compatiblity. Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html