From mboxrd@z Thu Jan 1 00:00:00 1970 From: dinguyen@altera.com (Dinh Nguyen) Date: Wed, 24 Apr 2013 17:44:42 -0500 Subject: dw_apb_timer_of.c: remove parts that were picoxcell-specific In-Reply-To: <20130423105827.GA6983@amd.pavel.ucw.cz> References: <20130423105827.GA6983@amd.pavel.ucw.cz> Message-ID: <1366843482.29992.4.camel@linux-builds1> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Pavel, On Tue, 2013-04-23 at 12:58 +0200, ZY - pavel wrote: > It seems we made a mistake when creating dw_apb_timer_of.c: > picoxcell sched_clock parts were not related to dw_apb_timer, yet > we moved them to dw_apb_timer_of, and tried to use them on socfpga. > > This results in system where user/system time is not measured properly, > as demonstrated by > > time dd if=/dev/urandom of=/dev/zero bs=100000 count=100 > > . > > So this patch: > > 1) moves picoxcell sched_clock parts back to picoxcell > > 2) adds support to use dw_apb_timer s as sched_clock. Picoxcell could > consider switching to these > > 3) adds missing of_node_put() in dw_apb_timer_init(). > > Tested on socfpga, soc-next (3.9-rc6) based tree. > > Signed-off-by: Pavel Machek > > diff --git a/arch/arm/mach-picoxcell/common.c b/arch/arm/mach-picoxcell/common.c > index 70b441a..22759f5 100644 > --- a/arch/arm/mach-picoxcell/common.c > +++ b/arch/arm/mach-picoxcell/common.c > @@ -84,11 +84,39 @@ static void picoxcell_wdt_restart(char mode, const char *cmd) > } > } > > +static const struct of_device_id picochip_rtc_ids[] __initconst = { > + { .compatible = "picochip,pc3x2-rtc" }, > + { /* Sentinel */ }, > +}; > + > +static void __iomem *sched_io_base; > + > +static u32 read_sched_clock(void) > +{ > + return __raw_readl(sched_io_base); > +} > + > +static void __init timer_init(void) > +{ > + u32 rate; > + > + dw_apb_timer_init(0); > + > + sched_timer = of_find_matching_node(timer, osctimer_ids); > + if (!sched_timer) > + panic("No suitable timer for scheduler clock\n"); > + > + timer_get_base_and_rate(sched_timer, &sched_io_base, &rate); > + of_node_put(sched_timer); > + > + setup_sched_clock(read_sched_clock, 32, rate); > +} > + > DT_MACHINE_START(PICOXCELL, "Picochip picoXcell") > .map_io = picoxcell_map_io, > .nr_irqs = NR_IRQS_LEGACY, > .init_irq = irqchip_init, > - .init_time = dw_apb_timer_init, > + .init_time = timer_init, > .init_machine = picoxcell_init_machine, > .dt_compat = picoxcell_dt_match, > .restart = picoxcell_wdt_restart, > diff --git a/arch/arm/mach-socfpga/socfpga.c b/arch/arm/mach-socfpga/socfpga.c > index 46a0513..3a030e5 100644 > --- a/arch/arm/mach-socfpga/socfpga.c > +++ b/arch/arm/mach-socfpga/socfpga.c > @@ -116,11 +116,17 @@ static const char *altera_dt_match[] = { > NULL > }; > > +static void __init timer_init(void) > +{ > + dw_apb_timer_init(1); > +} > + > + > DT_MACHINE_START(SOCFPGA, "Altera SOCFPGA") > .smp = smp_ops(socfpga_smp_ops), > .map_io = socfpga_map_io, > .init_irq = socfpga_init_irq, > - .init_time = dw_apb_timer_init, > + .init_time = timer_init, > .init_machine = socfpga_cyclone5_init, > .restart = socfpga_cyclone5_restart, > .dt_compat = altera_dt_match, > diff --git a/drivers/clocksource/dw_apb_timer.c b/drivers/clocksource/dw_apb_timer.c > index 8c2a35f..460ac99 100644 > --- a/drivers/clocksource/dw_apb_timer.c > +++ b/drivers/clocksource/dw_apb_timer.c > @@ -21,12 +21,6 @@ > #define APBT_MIN_PERIOD 4 > #define APBT_MIN_DELTA_USEC 200 > > -#define APBTMR_N_LOAD_COUNT 0x00 > -#define APBTMR_N_CURRENT_VALUE 0x04 > -#define APBTMR_N_CONTROL 0x08 > -#define APBTMR_N_EOI 0x0c > -#define APBTMR_N_INT_STATUS 0x10 > - > #define APBTMRS_INT_STATUS 0xa0 > #define APBTMRS_EOI 0xa4 > #define APBTMRS_RAW_INT_STATUS 0xa8 > diff --git a/drivers/clocksource/dw_apb_timer_of.c b/drivers/clocksource/dw_apb_timer_of.c > index ab09ed3..ac4ea00 100644 > --- a/drivers/clocksource/dw_apb_timer_of.c > +++ b/drivers/clocksource/dw_apb_timer_of.c > @@ -57,7 +57,16 @@ static void add_clockevent(struct device_node *event_timer) > dw_apb_clockevent_register(ced); > } > > -static void add_clocksource(struct device_node *source_timer) > +static void __iomem *sched_io_base; > + > +/* This is actually same as __apbt_read_clocksource(), but with > + different interface */ > +static u32 read_sched_clock_sptimer(void) > +{ > + return ~__raw_readl(sched_io_base + APBTMR_N_CURRENT_VALUE); > +} > + > +static void add_clocksource(struct device_node *source_timer, int use_as_scheduler) > { > void __iomem *iobase; > struct dw_apb_clocksource *cs; > @@ -71,45 +80,34 @@ static void add_clocksource(struct device_node *source_timer) > > dw_apb_clocksource_start(cs); > dw_apb_clocksource_register(cs); > -} > > -static void __iomem *sched_io_base; > - > -static u32 read_sched_clock(void) > -{ > - return __raw_readl(sched_io_base); > + if (use_as_scheduler) { > + sched_io_base = iobase; > + setup_sched_clock(read_sched_clock_sptimer, 32, rate); > + } > } > > -static const struct of_device_id sptimer_ids[] __initconst = { > - { .compatible = "picochip,pc3x2-rtc" }, > +static const struct of_device_id osctimer_ids[] __initconst = { > + { .compatible = "picochip,pc3x2-timer" }, > + { .compatible = "snps,dw-apb-timer-osc" }, > { .compatible = "snps,dw-apb-timer-sp" }, > - { /* Sentinel */ }, > + { /* Sentinel */ }, > }; > > -static void init_sched_clock(void) > -{ > - struct device_node *sched_timer; > - u32 rate; > - > - sched_timer = of_find_matching_node(NULL, sptimer_ids); > - if (!sched_timer) > - panic("No RTC for sched clock to use"); > - > - timer_get_base_and_rate(sched_timer, &sched_io_base, &rate); > - of_node_put(sched_timer); > +/* > + You don't have to use dw_apb_timer for scheduler clock, > + this should also work fine on arm: > > - setup_sched_clock(read_sched_clock, 32, rate); > -} > + twd_local_timer_of_register(); > + arch_timer_of_register(); > + arch_timer_sched_clock_init(); > +*/ > > -static const struct of_device_id osctimer_ids[] __initconst = { > - { .compatible = "picochip,pc3x2-timer" }, > - { .compatible = "snps,dw-apb-timer-osc" }, > - {}, > -}; > > -void __init dw_apb_timer_init(void) > +void __init dw_apb_timer_init(int use_as_scheduler) > { > struct device_node *event_timer, *source_timer; > + u32 rate; You're not using rate anywhere in this function. drivers/clocksource/dw_apb_timer_of.c: In function ?dw_apb_timer_init?: drivers/clocksource/dw_apb_timer_of.c:110:6: warning: unused variable ?rate? > > event_timer = of_find_matching_node(NULL, osctimer_ids); > if (!event_timer) > @@ -119,9 +117,8 @@ void __init dw_apb_timer_init(void) > source_timer = of_find_matching_node(event_timer, osctimer_ids); > if (!source_timer) > panic("No timer for clocksource"); > - add_clocksource(source_timer); > + add_clocksource(source_timer, use_as_scheduler); > > + of_node_put(event_timer); > of_node_put(source_timer); > - > - init_sched_clock(); > } > diff --git a/include/linux/dw_apb_timer.h b/include/linux/dw_apb_timer.h > index dd755ce..d503245 100644 > --- a/include/linux/dw_apb_timer.h > +++ b/include/linux/dw_apb_timer.h > @@ -17,6 +17,12 @@ > #include > #include > > +#define APBTMR_N_LOAD_COUNT 0x00 > +#define APBTMR_N_CURRENT_VALUE 0x04 > +#define APBTMR_N_CONTROL 0x08 > +#define APBTMR_N_EOI 0x0c > +#define APBTMR_N_INT_STATUS 0x10 > + > #define APBTMRS_REG_SIZE 0x14 > > struct dw_apb_timer { > @@ -53,5 +59,5 @@ void dw_apb_clocksource_start(struct dw_apb_clocksource *dw_cs); > cycle_t dw_apb_clocksource_read(struct dw_apb_clocksource *dw_cs); > void dw_apb_clocksource_unregister(struct dw_apb_clocksource *dw_cs); > > -extern void dw_apb_timer_init(void); > +extern void dw_apb_timer_init(int); > #endif /* __DW_APB_TIMER_H__ */ On SOCFPGA: Tested-by: Dinh Nguyen >