| Message ID | E1QJhNe-0000yh-HS@rmk-PC.arm.linux.org.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, May 10, 2011 at 08:29:18AM +0100, Russell King - ARM Linux wrote: > Add a generic mmio clocksource, covering both 32-bit and 16-bit register > access sizes, for up or down counters. This can be used to easily > create clocksources for simple counter-based implementations. > > Cc: Alessandro Rubini <rubini@unipv.it> > Cc: Colin Cross <ccross@android.com> > Cc: Eric Miao <eric.y.miao@gmail.com> > Cc: Erik Gilling <konkers@android.com> > Cc: "Hans J. Koch" <hjk@hansjkoch.de> > Cc: Imre Kaloz <kaloz@openwrt.org> > Cc: Krzysztof Halasa <khc@pm.waw.pl> > Cc: Kukjin Kim <kgene.kim@samsung.com> > Cc: Lennert Buytenhek <kernel@wantstofly.org> > Cc: Linus Walleij <linus.walleij@stericsson.com> > Cc: linux-omap@vger.kernel.org > Cc: Nicolas Pitre <nico@fluxnic.net> > Cc: Olof Johansson <olof@lixom.net> > Cc: Sascha Hauer <kernel@pengutronix.de> > Cc: Tony Lindgren <tony@atomide.com> > Cc: Viresh Kumar <viresh.kumar@st.com> > Cc: Wan ZongShun <mcuos.com@gmail.com> > Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> > --- > drivers/Kconfig | 3 ++ > drivers/clocksource/Kconfig | 2 + > drivers/clocksource/Makefile | 1 + > drivers/clocksource/mmio.c | 72 ++++++++++++++++++++++++++++++++++++++++++ > include/linux/clocksource.h | 8 +++++ > 5 files changed, 86 insertions(+), 0 deletions(-) > create mode 100644 drivers/clocksource/Kconfig > create mode 100644 drivers/clocksource/mmio.c > > diff --git a/drivers/Kconfig b/drivers/Kconfig > index 177c7d1..557a469 100644 > --- a/drivers/Kconfig > +++ b/drivers/Kconfig > @@ -119,4 +119,7 @@ source "drivers/platform/Kconfig" > source "drivers/clk/Kconfig" > > source "drivers/hwspinlock/Kconfig" > + > +source "drivers/clocksource/Kconfig" > + > endmenu > diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig > new file mode 100644 > index 0000000..47f37b1 > --- /dev/null > +++ b/drivers/clocksource/Kconfig > @@ -0,0 +1,2 @@ > +config CLKSRC_MMIO > + bool > diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile > index be61ece..9b2ba29 100644 > --- a/drivers/clocksource/Makefile > +++ b/drivers/clocksource/Makefile > @@ -6,3 +6,4 @@ obj-$(CONFIG_CS5535_CLOCK_EVENT_SRC) += cs5535-clockevt.o > obj-$(CONFIG_SH_TIMER_CMT) += sh_cmt.o > obj-$(CONFIG_SH_TIMER_MTU2) += sh_mtu2.o > obj-$(CONFIG_SH_TIMER_TMU) += sh_tmu.o > +obj-$(CONFIG_CLKSRC_MMIO) += mmio.o > diff --git a/drivers/clocksource/mmio.c b/drivers/clocksource/mmio.c > new file mode 100644 > index 0000000..71ad3a3 > --- /dev/null > +++ b/drivers/clocksource/mmio.c > @@ -0,0 +1,72 @@ > +/* > + * Generic MMIO clocksource support > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + */ > +#include <linux/clocksource.h> > +#include <linux/errno.h> > +#include <linux/init.h> > +#include <linux/slab.h> > + > +struct clocksource_mmio { > + void __iomem *reg; > + struct clocksource clksrc; > +}; > + > +static inline struct clocksource_mmio *to_mmio_clksrc(struct clocksource *c) > +{ > + return container_of(c, struct clocksource_mmio, clksrc); > +} > + > +cycle_t clocksource_mmio_readl_up(struct clocksource *c) > +{ > + return readl_relaxed(to_mmio_clksrc(c)->reg); > +} > + > +cycle_t clocksource_mmio_readl_down(struct clocksource *c) > +{ > + return ~readl_relaxed(to_mmio_clksrc(c)->reg); > +} > + > +cycle_t clocksource_mmio_readw_up(struct clocksource *c) > +{ > + return readw_relaxed(to_mmio_clksrc(c)->reg); > +} > + > +cycle_t clocksource_mmio_readw_down(struct clocksource *c) > +{ > + return ~(unsigned)readw_relaxed(to_mmio_clksrc(c)->reg); > +} > + > +/** > + * clocksource_mmio_init - Initialize a simple mmio based clocksource > + * @base: Virtual address of the clock readout register > + * @name: Name of the clocksource > + * @hz: Frequency of the clocksource in Hz > + * @rating: Rating of the clocksource > + * @bits: Number of valid bits > + * @read: One of clocksource_mmio_read*() above > + */ > +int __init clocksource_mmio_init(void __iomem *base, const char *name, > + unsigned long hz, int rating, unsigned bits, > + cycle_t (*read)(struct clocksource *)) > +{ > + struct clocksource_mmio *cs; > + > + if (bits > 32 || bits < 16) > + return -EINVAL; > + > + cs = kzalloc(sizeof(struct clocksource_mmio), GFP_KERNEL); > + if (!cs) > + return -ENOMEM; > + > + cs->clksrc.name = name; > + cs->clksrc.rating = rating; > + cs->clksrc.read = read; > + cs->clksrc.mask = CLOCKSOURCE_MASK(bits); > + cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS; You forgot to initialize cs->reg. With this: Tested-by: Sascha Hauer <s.hauer@pengutronix.de> (For the i.MX part) Sascha
On Tue, May 10, 2011 at 10:38:41AM +0200, Sascha Hauer wrote: > You forgot to initialize cs->reg. With this: Damnit. Fixed. > Tested-by: Sascha Hauer <s.hauer@pengutronix.de> Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, May 10, 2011 at 08:29:18AM +0100, Russell King - ARM Linux wrote: > +cycle_t clocksource_mmio_readl_up(struct clocksource *c) > +{ > + return readl_relaxed(to_mmio_clksrc(c)->reg); > +} > + > +cycle_t clocksource_mmio_readl_down(struct clocksource *c) > +{ > + return ~readl_relaxed(to_mmio_clksrc(c)->reg); > +} > + > +cycle_t clocksource_mmio_readw_up(struct clocksource *c) > +{ > + return readw_relaxed(to_mmio_clksrc(c)->reg); > +} > + > +cycle_t clocksource_mmio_readw_down(struct clocksource *c) > +{ > + return ~(unsigned)readw_relaxed(to_mmio_clksrc(c)->reg); > +} I probably ought to point out why that cast is there: readw* returns an u16. u16 will be promoted to 'int' by the compiler, then not'd, and then extended to cycle_t (64-bit). This extension is a signed extension which not only results in more code than required, but also results in a delay slot not being filled. It's the u16 -> signed int -> cycle_t which causes the signed extension. u16 -> cycle_t doesn't involve changing the signed-ness of the type, so doesn't suffer. Neither does readl as it returns a u32 which doesn't need any promotion to an int type. So, rather than allow the compiler to do automatic promotion to a signed int, the cast is there to ensure that it becomes an unsigned int instead. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 05/10/2011 12:59 PM, Russell King - ARM Linux wrote: > Add a generic mmio clocksource, covering both 32-bit and 16-bit register > access sizes, for up or down counters. This can be used to easily > create clocksources for simple counter-based implementations. > > Cc: Alessandro Rubini <rubini@unipv.it> > Cc: Colin Cross <ccross@android.com> > Cc: Eric Miao <eric.y.miao@gmail.com> > Cc: Erik Gilling <konkers@android.com> > Cc: "Hans J. Koch" <hjk@hansjkoch.de> > Cc: Imre Kaloz <kaloz@openwrt.org> > Cc: Krzysztof Halasa <khc@pm.waw.pl> > Cc: Kukjin Kim <kgene.kim@samsung.com> > Cc: Lennert Buytenhek <kernel@wantstofly.org> > Cc: Linus Walleij <linus.walleij@stericsson.com> > Cc: linux-omap@vger.kernel.org > Cc: Nicolas Pitre <nico@fluxnic.net> > Cc: Olof Johansson <olof@lixom.net> > Cc: Sascha Hauer <kernel@pengutronix.de> > Cc: Tony Lindgren <tony@atomide.com> > Cc: Viresh Kumar <viresh.kumar@st.com> > Cc: Wan ZongShun <mcuos.com@gmail.com> > Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> > --- > drivers/Kconfig | 3 ++ > drivers/clocksource/Kconfig | 2 + > drivers/clocksource/Makefile | 1 + > drivers/clocksource/mmio.c | 72 ++++++++++++++++++++++++++++++++++++++++++ > include/linux/clocksource.h | 8 +++++ > 5 files changed, 86 insertions(+), 0 deletions(-) > create mode 100644 drivers/clocksource/Kconfig > create mode 100644 drivers/clocksource/mmio.c > > diff --git a/drivers/Kconfig b/drivers/Kconfig > index 177c7d1..557a469 100644 > --- a/drivers/Kconfig > +++ b/drivers/Kconfig > @@ -119,4 +119,7 @@ source "drivers/platform/Kconfig" > source "drivers/clk/Kconfig" > > source "drivers/hwspinlock/Kconfig" > + > +source "drivers/clocksource/Kconfig" > + > endmenu > diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig > new file mode 100644 > index 0000000..47f37b1 > --- /dev/null > +++ b/drivers/clocksource/Kconfig > @@ -0,0 +1,2 @@ > +config CLKSRC_MMIO > + bool > diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile > index be61ece..9b2ba29 100644 > --- a/drivers/clocksource/Makefile > +++ b/drivers/clocksource/Makefile > @@ -6,3 +6,4 @@ obj-$(CONFIG_CS5535_CLOCK_EVENT_SRC) += cs5535-clockevt.o > obj-$(CONFIG_SH_TIMER_CMT) += sh_cmt.o > obj-$(CONFIG_SH_TIMER_MTU2) += sh_mtu2.o > obj-$(CONFIG_SH_TIMER_TMU) += sh_tmu.o > +obj-$(CONFIG_CLKSRC_MMIO) += mmio.o > diff --git a/drivers/clocksource/mmio.c b/drivers/clocksource/mmio.c > new file mode 100644 > index 0000000..71ad3a3 > --- /dev/null > +++ b/drivers/clocksource/mmio.c > @@ -0,0 +1,72 @@ > +/* > + * Generic MMIO clocksource support > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + */ > +#include <linux/clocksource.h> > +#include <linux/errno.h> > +#include <linux/init.h> > +#include <linux/slab.h> > + > +struct clocksource_mmio { > + void __iomem *reg; > + struct clocksource clksrc; > +}; > + > +static inline struct clocksource_mmio *to_mmio_clksrc(struct clocksource *c) > +{ > + return container_of(c, struct clocksource_mmio, clksrc); > +} > + > +cycle_t clocksource_mmio_readl_up(struct clocksource *c) > +{ > + return readl_relaxed(to_mmio_clksrc(c)->reg); > +} > + > +cycle_t clocksource_mmio_readl_down(struct clocksource *c) > +{ > + return ~readl_relaxed(to_mmio_clksrc(c)->reg); > +} > + > +cycle_t clocksource_mmio_readw_up(struct clocksource *c) > +{ > + return readw_relaxed(to_mmio_clksrc(c)->reg); > +} > + > +cycle_t clocksource_mmio_readw_down(struct clocksource *c) > +{ > + return ~(unsigned)readw_relaxed(to_mmio_clksrc(c)->reg); > +} > + > +/** > + * clocksource_mmio_init - Initialize a simple mmio based clocksource > + * @base: Virtual address of the clock readout register > + * @name: Name of the clocksource > + * @hz: Frequency of the clocksource in Hz > + * @rating: Rating of the clocksource > + * @bits: Number of valid bits > + * @read: One of clocksource_mmio_read*() above > + */ > +int __init clocksource_mmio_init(void __iomem *base, const char *name, > + unsigned long hz, int rating, unsigned bits, > + cycle_t (*read)(struct clocksource *)) > +{ > + struct clocksource_mmio *cs; > + > + if (bits > 32 || bits < 16) > + return -EINVAL; > + > + cs = kzalloc(sizeof(struct clocksource_mmio), GFP_KERNEL); > + if (!cs) > + return -ENOMEM; > + > + cs->clksrc.name = name; > + cs->clksrc.rating = rating; > + cs->clksrc.read = read; > + cs->clksrc.mask = CLOCKSOURCE_MASK(bits); > + cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS; > + > + return clocksource_register_hz(&cs->clksrc, hz); > +} > diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h > index 94c1f38..a3558fd 100644 > --- a/include/linux/clocksource.h > +++ b/include/linux/clocksource.h > @@ -341,4 +341,12 @@ static inline void update_vsyscall_tz(void) > > extern void timekeeping_notify(struct clocksource *clock); > > +extern cycle_t clocksource_mmio_readl_up(struct clocksource *); > +extern cycle_t clocksource_mmio_readl_down(struct clocksource *); > +extern cycle_t clocksource_mmio_readw_up(struct clocksource *); > +extern cycle_t clocksource_mmio_readw_down(struct clocksource *); > + > +extern int clocksource_mmio_init(void __iomem *, const char *, > + unsigned long, int, unsigned, cycle_t (*)(struct clocksource *)); > + > #endif /* _LINUX_CLOCKSOURCE_H */ With cs->reg initialized, Reviewed-by: Viresh Kumar <viresh.kumar@st.com>
* Russell King - ARM Linux <linux@arm.linux.org.uk> [110510 01:44]: > On Tue, May 10, 2011 at 10:38:41AM +0200, Sascha Hauer wrote: > > You forgot to initialize cs->reg. With this: > > Damnit. Fixed. > > > Tested-by: Sascha Hauer <s.hauer@pengutronix.de> With cs->reg initialization and CONFIG_OMAP_MPU_TIMER=y things boot tested on omap1 osk: Tested-by: Tony Lindgren <tony@atomide.com> -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, 10 May 2011, Russell King - ARM Linux wrote: > Add a generic mmio clocksource, covering both 32-bit and 16-bit register > access sizes, for up or down counters. This can be used to easily > create clocksources for simple counter-based implementations. > > Cc: Alessandro Rubini <rubini@unipv.it> > Cc: Colin Cross <ccross@android.com> > Cc: Eric Miao <eric.y.miao@gmail.com> > Cc: Erik Gilling <konkers@android.com> > Cc: "Hans J. Koch" <hjk@hansjkoch.de> > Cc: Imre Kaloz <kaloz@openwrt.org> > Cc: Krzysztof Halasa <khc@pm.waw.pl> > Cc: Kukjin Kim <kgene.kim@samsung.com> > Cc: Lennert Buytenhek <kernel@wantstofly.org> > Cc: Linus Walleij <linus.walleij@stericsson.com> > Cc: linux-omap@vger.kernel.org > Cc: Nicolas Pitre <nico@fluxnic.net> > Cc: Olof Johansson <olof@lixom.net> > Cc: Sascha Hauer <kernel@pengutronix.de> > Cc: Tony Lindgren <tony@atomide.com> > Cc: Viresh Kumar <viresh.kumar@st.com> > Cc: Wan ZongShun <mcuos.com@gmail.com> > Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Please take this through the ARM tree. It's not conflicting with anything in my tree. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/Kconfig b/drivers/Kconfig index 177c7d1..557a469 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -119,4 +119,7 @@ source "drivers/platform/Kconfig" source "drivers/clk/Kconfig" source "drivers/hwspinlock/Kconfig" + +source "drivers/clocksource/Kconfig" + endmenu diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig new file mode 100644 index 0000000..47f37b1 --- /dev/null +++ b/drivers/clocksource/Kconfig @@ -0,0 +1,2 @@ +config CLKSRC_MMIO + bool diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index be61ece..9b2ba29 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -6,3 +6,4 @@ obj-$(CONFIG_CS5535_CLOCK_EVENT_SRC) += cs5535-clockevt.o obj-$(CONFIG_SH_TIMER_CMT) += sh_cmt.o obj-$(CONFIG_SH_TIMER_MTU2) += sh_mtu2.o obj-$(CONFIG_SH_TIMER_TMU) += sh_tmu.o +obj-$(CONFIG_CLKSRC_MMIO) += mmio.o diff --git a/drivers/clocksource/mmio.c b/drivers/clocksource/mmio.c new file mode 100644 index 0000000..71ad3a3 --- /dev/null +++ b/drivers/clocksource/mmio.c @@ -0,0 +1,72 @@ +/* + * Generic MMIO clocksource support + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/clocksource.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/slab.h> + +struct clocksource_mmio { + void __iomem *reg; + struct clocksource clksrc; +}; + +static inline struct clocksource_mmio *to_mmio_clksrc(struct clocksource *c) +{ + return container_of(c, struct clocksource_mmio, clksrc); +} + +cycle_t clocksource_mmio_readl_up(struct clocksource *c) +{ + return readl_relaxed(to_mmio_clksrc(c)->reg); +} + +cycle_t clocksource_mmio_readl_down(struct clocksource *c) +{ + return ~readl_relaxed(to_mmio_clksrc(c)->reg); +} + +cycle_t clocksource_mmio_readw_up(struct clocksource *c) +{ + return readw_relaxed(to_mmio_clksrc(c)->reg); +} + +cycle_t clocksource_mmio_readw_down(struct clocksource *c) +{ + return ~(unsigned)readw_relaxed(to_mmio_clksrc(c)->reg); +} + +/** + * clocksource_mmio_init - Initialize a simple mmio based clocksource + * @base: Virtual address of the clock readout register + * @name: Name of the clocksource + * @hz: Frequency of the clocksource in Hz + * @rating: Rating of the clocksource + * @bits: Number of valid bits + * @read: One of clocksource_mmio_read*() above + */ +int __init clocksource_mmio_init(void __iomem *base, const char *name, + unsigned long hz, int rating, unsigned bits, + cycle_t (*read)(struct clocksource *)) +{ + struct clocksource_mmio *cs; + + if (bits > 32 || bits < 16) + return -EINVAL; + + cs = kzalloc(sizeof(struct clocksource_mmio), GFP_KERNEL); + if (!cs) + return -ENOMEM; + + cs->clksrc.name = name; + cs->clksrc.rating = rating; + cs->clksrc.read = read; + cs->clksrc.mask = CLOCKSOURCE_MASK(bits); + cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS; + + return clocksource_register_hz(&cs->clksrc, hz); +} diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 94c1f38..a3558fd 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -341,4 +341,12 @@ static inline void update_vsyscall_tz(void) extern void timekeeping_notify(struct clocksource *clock); +extern cycle_t clocksource_mmio_readl_up(struct clocksource *); +extern cycle_t clocksource_mmio_readl_down(struct clocksource *); +extern cycle_t clocksource_mmio_readw_up(struct clocksource *); +extern cycle_t clocksource_mmio_readw_down(struct clocksource *); + +extern int clocksource_mmio_init(void __iomem *, const char *, + unsigned long, int, unsigned, cycle_t (*)(struct clocksource *)); + #endif /* _LINUX_CLOCKSOURCE_H */
Add a generic mmio clocksource, covering both 32-bit and 16-bit register access sizes, for up or down counters. This can be used to easily create clocksources for simple counter-based implementations. Cc: Alessandro Rubini <rubini@unipv.it> Cc: Colin Cross <ccross@android.com> Cc: Eric Miao <eric.y.miao@gmail.com> Cc: Erik Gilling <konkers@android.com> Cc: "Hans J. Koch" <hjk@hansjkoch.de> Cc: Imre Kaloz <kaloz@openwrt.org> Cc: Krzysztof Halasa <khc@pm.waw.pl> Cc: Kukjin Kim <kgene.kim@samsung.com> Cc: Lennert Buytenhek <kernel@wantstofly.org> Cc: Linus Walleij <linus.walleij@stericsson.com> Cc: linux-omap@vger.kernel.org Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Olof Johansson <olof@lixom.net> Cc: Sascha Hauer <kernel@pengutronix.de> Cc: Tony Lindgren <tony@atomide.com> Cc: Viresh Kumar <viresh.kumar@st.com> Cc: Wan ZongShun <mcuos.com@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> --- drivers/Kconfig | 3 ++ drivers/clocksource/Kconfig | 2 + drivers/clocksource/Makefile | 1 + drivers/clocksource/mmio.c | 72 ++++++++++++++++++++++++++++++++++++++++++ include/linux/clocksource.h | 8 +++++ 5 files changed, 86 insertions(+), 0 deletions(-) create mode 100644 drivers/clocksource/Kconfig create mode 100644 drivers/clocksource/mmio.c