| Message ID | 1361033044-27629-13-git-send-email-tomasz.figa@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 02/16/2013 10:44 AM, Tomasz Figa wrote: > This patch adds support for parsing all platform-specific data from > Device Tree and instantiation using clocksource_of_init to samsung-time > clocksource driver. > +Optional properties: > +- samsung,source-timer: index of timer to be used as clocksource (defaults to 4) > +- samsung,event-timer: index of timer to be used as clock event (defaults to 3) This is Linux specific, not a h/w property. Define the h/w properties of the timers so that Linux can decide which timer to use. See the omap2 timers for an example. > +- samsung,prescale-divisor: PWM prescaler divisor (from 1 to 256) > +- samsung,divisor: PWM main divider divisor (1, 2, 4, 8 or 16) > + > +Example: > + timer@7f006000 { > + compatible = "samsung,s3c64xx-pwm-timer"; > + reg = <0x7f006000 0x1000>; > + interrupt-parent = <&vic0>; > + interrupts = <23>, <24>, <25>, <27>, <28>; > + samsung,source-timer = <4>; > + samsung,event-timer = <3>; > + samsung,prescale-divisor = <2>; > + samsung,divisor = <1>; > + }; > diff --git a/drivers/clocksource/samsung-time.c b/drivers/clocksource/samsung-time.c > index 4134811..76a15ca 100644 > --- a/drivers/clocksource/samsung-time.c > +++ b/drivers/clocksource/samsung-time.c > @@ -14,6 +14,9 @@ > #include <linux/err.h> > #include <linux/clk.h> > #include <linux/clockchips.h> > +#include <linux/of.h> > +#include <linux/of_address.h> > +#include <linux/of_irq.h> > #include <linux/platform_device.h> > > #include <clocksource/samsung-time.h> > @@ -480,9 +483,12 @@ static void __init samsung_timer_resources(void) > unsigned long source_id = timer_source.source_id; > char devname[15]; > > - timer_base = ioremap_nocache(timer_variant.reg_base, SZ_4K); > - if (!timer_base) > - panic("failed to map timer registers"); > + if (!timer_base) { > + /* Compatibility fallback for non-DT platforms */ > + timer_base = ioremap_nocache(timer_variant.reg_base, SZ_4K); > + if (!timer_base) > + panic("failed to map timer registers"); > + } > > timerclk = clk_get(NULL, "timers"); > if (IS_ERR(timerclk)) > @@ -515,8 +521,102 @@ static void __init samsung_timer_resources(void) > clk_enable(tin_source); > } > > +enum { > + TYPE_S3C24XX, > + TYPE_S3C64XX, > +}; > + > +#ifdef CONFIG_OF > +static const struct of_device_id samsung_timer_ids[] = { > + { .compatible = "samsung,s3c24xx-pwm-timer", > + .data = (void *)TYPE_S3C24XX, }, > + { .compatible = "samsung,s3c64xx-pwm-timer", > + .data = (void *)TYPE_S3C64XX, }, Shouldn't need 2 match tables and the data here is kind of pointless when you can just use the compatible string. > + {}, > +}; > + > +static void samsung_timer_parse_dt(struct device_node *np, > + const struct of_device_id *match) > +{ > + int i; > + u32 val; > + > + timer_base = of_iomap(np, 0); > + if (!timer_base) > + panic("failed to map timer registers"); > + > + for (i = 0; i < SAMSUNG_PWM_NUM; ++i) > + timer_variant.irqs[i] = irq_of_parse_and_map(np, i); > + > + if (!timer_variant.irqs[timer_source.event_id]) > + panic("no clock event irq provided"); > + > + switch ((unsigned int)match->data) { > + case TYPE_S3C24XX: > + timer_variant.bits = 16; > + timer_variant.prescale = 25; > + timer_variant.prescale = 50; > + timer_variant.has_tint_cstat = false; > + break; > + case TYPE_S3C64XX: > + timer_variant.bits = 32; > + timer_variant.prescale = 2; > + timer_variant.divisor = 2; > + timer_variant.has_tint_cstat = true; > + break; > + } > + > + timer_source.source_id = 4; > + if (!of_property_read_u32(np, "samsung,source-timer", &val)) { > + if (val >= SAMSUNG_PWM_NUM) > + panic("samsung,source-timer property out of range"); > + timer_source.source_id = val; > + } > + > + timer_source.event_id = 3; > + if (!of_property_read_u32(np, "samsung,event-timer", &val)) { > + if (val >= SAMSUNG_PWM_NUM) > + panic("samsung,event-timer property out of range"); > + timer_source.event_id = val; > + } > + > + if (!of_property_read_u32(np, "samsung,prescale-divisor", &val)) { > + if (val < 1 || val > 256) > + panic("samsung,prescale-divisor property out of range"); > + timer_variant.prescale = val; > + } > + > + if (!of_property_read_u32(np, "samsung,divisor", &val)) { > + switch (val) { > + case 1: > + case 2: > + case 4: > + case 8: > + case 16: > + timer_variant.divisor = timer_variant.prescale * val; > + break; > + default: > + panic("invalid value of samsung,divisor property"); > + } > + } > +} > +#endif > + > void __init samsung_timer_init(void) > { > +#ifdef CONFIG_OF > + struct device_node *np; > + const struct of_device_id *match; > + > + if (of_have_populated_dt()) { Separate the OF and non-OF code to avoid this and the ifdef. > + np = of_find_matching_node_and_match(NULL, > + samsung_timer_ids, &match); > + if (!np) > + panic("timer node not found"); I have a patch to change this function to pass in the node ptr and avoid matching twice. It should be in arm-soc shortly after rc1. Rob > + > + samsung_timer_parse_dt(np, match); > + } > +#endif > if (!timer_source.source_id && !timer_source.event_id) > panic("timer sources not set (see samsung_set_timer_source)!\n"); > > @@ -527,3 +627,10 @@ void __init samsung_timer_init(void) > samsung_clockevent_init(); > samsung_clocksource_init(); > } > + > +#ifdef CONFIG_CLKSRC_OF > +CLOCKSOURCE_OF_DECLARE(s3c24xx_timer, > + "samsung,s3c24xx-pwm-timer", samsung_timer_init) > +CLOCKSOURCE_OF_DECLARE(s3c64xx_timer, > + "samsung,s3c64xx-pwm-timer", samsung_timer_init) > +#endif >
Hi, [...] > +static void samsung_timer_parse_dt(struct device_node *np, > + const struct of_device_id *match) > +{ > + int i; > + u32 val; > + > + timer_base = of_iomap(np, 0); > + if (!timer_base) > + panic("failed to map timer registers"); > + > + for (i = 0; i < SAMSUNG_PWM_NUM; ++i) > + timer_variant.irqs[i] = irq_of_parse_and_map(np, i); > + > + if (!timer_variant.irqs[timer_source.event_id]) > + panic("no clock event irq provided"); > + > + switch ((unsigned int)match->data) { > + case TYPE_S3C24XX: > + timer_variant.bits = 16; > + timer_variant.prescale = 25; > + timer_variant.prescale = 50; Redundant conflicting assignments here. Thanks, Mark.
diff --git a/Documentation/devicetree/bindings/arm/samsung-timer.txt b/Documentation/devicetree/bindings/arm/samsung-timer.txt new file mode 100644 index 0000000..179b7e4 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/samsung-timer.txt @@ -0,0 +1,33 @@ +* Samsung PWM timer + +Samsung SoCs contain PWM timer blocks which can be used for system clock source +and clock event timers. + +Be aware that this configuration is supported only on uniprocessor platforms. +For SMP SoCs, SMP-aware timers should be used, like MCT. + +Required properties: +- compatible : should be one of following: + samsung,s3c24xx-pwm-timer - for 16-bit timers present on S3C24xx + samsung,s3c64xx-pwm-timer - for 32-bit timers present on S3C64xx and newer +- reg: base address and size of register area +- interrupts: list of timer interrupts (one interrupt per timer, starting at + timer 0) + +Optional properties: +- samsung,source-timer: index of timer to be used as clocksource (defaults to 4) +- samsung,event-timer: index of timer to be used as clock event (defaults to 3) +- samsung,prescale-divisor: PWM prescaler divisor (from 1 to 256) +- samsung,divisor: PWM main divider divisor (1, 2, 4, 8 or 16) + +Example: + timer@7f006000 { + compatible = "samsung,s3c64xx-pwm-timer"; + reg = <0x7f006000 0x1000>; + interrupt-parent = <&vic0>; + interrupts = <23>, <24>, <25>, <27>, <28>; + samsung,source-timer = <4>; + samsung,event-timer = <3>; + samsung,prescale-divisor = <2>; + samsung,divisor = <1>; + }; diff --git a/drivers/clocksource/samsung-time.c b/drivers/clocksource/samsung-time.c index 4134811..76a15ca 100644 --- a/drivers/clocksource/samsung-time.c +++ b/drivers/clocksource/samsung-time.c @@ -14,6 +14,9 @@ #include <linux/err.h> #include <linux/clk.h> #include <linux/clockchips.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> #include <linux/platform_device.h> #include <clocksource/samsung-time.h> @@ -480,9 +483,12 @@ static void __init samsung_timer_resources(void) unsigned long source_id = timer_source.source_id; char devname[15]; - timer_base = ioremap_nocache(timer_variant.reg_base, SZ_4K); - if (!timer_base) - panic("failed to map timer registers"); + if (!timer_base) { + /* Compatibility fallback for non-DT platforms */ + timer_base = ioremap_nocache(timer_variant.reg_base, SZ_4K); + if (!timer_base) + panic("failed to map timer registers"); + } timerclk = clk_get(NULL, "timers"); if (IS_ERR(timerclk)) @@ -515,8 +521,102 @@ static void __init samsung_timer_resources(void) clk_enable(tin_source); } +enum { + TYPE_S3C24XX, + TYPE_S3C64XX, +}; + +#ifdef CONFIG_OF +static const struct of_device_id samsung_timer_ids[] = { + { .compatible = "samsung,s3c24xx-pwm-timer", + .data = (void *)TYPE_S3C24XX, }, + { .compatible = "samsung,s3c64xx-pwm-timer", + .data = (void *)TYPE_S3C64XX, }, + {}, +}; + +static void samsung_timer_parse_dt(struct device_node *np, + const struct of_device_id *match) +{ + int i; + u32 val; + + timer_base = of_iomap(np, 0); + if (!timer_base) + panic("failed to map timer registers"); + + for (i = 0; i < SAMSUNG_PWM_NUM; ++i) + timer_variant.irqs[i] = irq_of_parse_and_map(np, i); + + if (!timer_variant.irqs[timer_source.event_id]) + panic("no clock event irq provided"); + + switch ((unsigned int)match->data) { + case TYPE_S3C24XX: + timer_variant.bits = 16; + timer_variant.prescale = 25; + timer_variant.prescale = 50; + timer_variant.has_tint_cstat = false; + break; + case TYPE_S3C64XX: + timer_variant.bits = 32; + timer_variant.prescale = 2; + timer_variant.divisor = 2; + timer_variant.has_tint_cstat = true; + break; + } + + timer_source.source_id = 4; + if (!of_property_read_u32(np, "samsung,source-timer", &val)) { + if (val >= SAMSUNG_PWM_NUM) + panic("samsung,source-timer property out of range"); + timer_source.source_id = val; + } + + timer_source.event_id = 3; + if (!of_property_read_u32(np, "samsung,event-timer", &val)) { + if (val >= SAMSUNG_PWM_NUM) + panic("samsung,event-timer property out of range"); + timer_source.event_id = val; + } + + if (!of_property_read_u32(np, "samsung,prescale-divisor", &val)) { + if (val < 1 || val > 256) + panic("samsung,prescale-divisor property out of range"); + timer_variant.prescale = val; + } + + if (!of_property_read_u32(np, "samsung,divisor", &val)) { + switch (val) { + case 1: + case 2: + case 4: + case 8: + case 16: + timer_variant.divisor = timer_variant.prescale * val; + break; + default: + panic("invalid value of samsung,divisor property"); + } + } +} +#endif + void __init samsung_timer_init(void) { +#ifdef CONFIG_OF + struct device_node *np; + const struct of_device_id *match; + + if (of_have_populated_dt()) { + np = of_find_matching_node_and_match(NULL, + samsung_timer_ids, &match); + if (!np) + panic("timer node not found"); + + samsung_timer_parse_dt(np, match); + } +#endif if (!timer_source.source_id && !timer_source.event_id) panic("timer sources not set (see samsung_set_timer_source)!\n"); @@ -527,3 +627,10 @@ void __init samsung_timer_init(void) samsung_clockevent_init(); samsung_clocksource_init(); } + +#ifdef CONFIG_CLKSRC_OF +CLOCKSOURCE_OF_DECLARE(s3c24xx_timer, + "samsung,s3c24xx-pwm-timer", samsung_timer_init) +CLOCKSOURCE_OF_DECLARE(s3c64xx_timer, + "samsung,s3c64xx-pwm-timer", samsung_timer_init) +#endif
This patch adds support for parsing all platform-specific data from Device Tree and instantiation using clocksource_of_init to samsung-time clocksource driver. Cc: devicetree-discuss@lists.ozlabs.org Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com> --- .../devicetree/bindings/arm/samsung-timer.txt | 33 ++++++ drivers/clocksource/samsung-time.c | 113 ++++++++++++++++++++- 2 files changed, 143 insertions(+), 3 deletions(-) create mode 100644 Documentation/devicetree/bindings/arm/samsung-timer.txt