| Message ID | 1471331895-29887-4-git-send-email-sjitindarsingh@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Aug 16, 2016 at 05:18:14PM +1000, Suraj Jitindar Singh wrote: > It would be nice if we had a generic sleep function which could be used > in unit tests, add one. > > Add the variable tb_hz used to store the time base frequency which is read > from the device tree on setup. > > Add functions msleep, usleep and sleep in processor.c to sleep for a given > number of milliseconds, microseconds and time base ticks respectively. Above you talk about adding *sleep functions, but below you add *delay functions. > > Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> > --- > > Change Log: > > V2 -> V3: > - Add patch to series > > Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> > --- > lib/powerpc/asm/processor.h | 19 +++++++++++++++++++ > lib/powerpc/asm/setup.h | 2 ++ > lib/powerpc/processor.c | 13 +++++++++++++ > lib/powerpc/setup.c | 12 ++++++++++++ > 4 files changed, 46 insertions(+) > > diff --git a/lib/powerpc/asm/processor.h b/lib/powerpc/asm/processor.h > index 09692bd..9554e08 100644 > --- a/lib/powerpc/asm/processor.h > +++ b/lib/powerpc/asm/processor.h > @@ -1,11 +1,30 @@ > #ifndef _ASMPOWERPC_PROCESSOR_H_ > #define _ASMPOWERPC_PROCESSOR_H_ > > +#include <libcflat.h> > #include <asm/ptrace.h> > > +#define cpu_relax() asm volatile ("" : : : "memory") Please add this to lib/asm-generic/barrier.h, then lib/ppc64/asm/barrier.h will pick it up from there and you'll just need to make sure you include asm/barrier.h in processor.c > + > #ifndef __ASSEMBLY__ > void handle_exception(int trap, void (*func)(struct pt_regs *, void *), void *); > void do_handle_exception(struct pt_regs *regs); > #endif /* __ASSEMBLY__ */ > > +static inline uint64_t get_tb(void) > +{ > + uint64_t tb; > + asm volatile ("mfspr %[tb],268" : [tb] "=r" (tb)); > + return tb; > +} > + > +extern void delay(uint64_t cycles); > +extern void udelay(uint64_t us); > + > +static inline void mdelay(uint64_t ms) > +{ > + while (ms--) > + udelay(1000); > +} > + > #endif /* _ASMPOWERPC_PROCESSOR_H_ */ > diff --git a/lib/powerpc/asm/setup.h b/lib/powerpc/asm/setup.h > index b1e1e5a..23b4156 100644 > --- a/lib/powerpc/asm/setup.h > +++ b/lib/powerpc/asm/setup.h > @@ -11,6 +11,8 @@ > extern u32 cpus[NR_CPUS]; > extern int nr_cpus; > > +extern uint64_t tb_hz; > + > #define NR_MEM_REGIONS 8 > #define MR_F_PRIMARY (1U << 0) > struct mem_region { > diff --git a/lib/powerpc/processor.c b/lib/powerpc/processor.c > index a78bc3c..c84bae5 100644 > --- a/lib/powerpc/processor.c > +++ b/lib/powerpc/processor.c > @@ -5,6 +5,7 @@ > #include <libcflat.h> > #include <asm/processor.h> > #include <asm/ptrace.h> > +#include <asm/setup.h> > > static struct { > void (*func)(struct pt_regs *, void *data); > @@ -36,3 +37,15 @@ void do_handle_exception(struct pt_regs *regs) > printf("unhandled cpu exception 0x%lx\n", regs->trap); > abort(); > } > + > +void delay(uint64_t cycles) > +{ > + uint64_t start = get_tb(); > + while((get_tb() - start) < cycles) > + cpu_relax(); > +} > + > +void udelay(uint64_t us) > +{ > + delay((us * tb_hz) / 1000000); > +} > diff --git a/lib/powerpc/setup.c b/lib/powerpc/setup.c > index e3d2afa..e7fa525 100644 > --- a/lib/powerpc/setup.c > +++ b/lib/powerpc/setup.c > @@ -24,6 +24,7 @@ extern void setup_args_progname(const char *args); > > u32 cpus[NR_CPUS] = { [0 ... NR_CPUS-1] = (~0U) }; > int nr_cpus; > +uint64_t tb_hz; > > struct mem_region mem_regions[NR_MEM_REGIONS]; > phys_addr_t __physical_start, __physical_end; > @@ -51,6 +52,17 @@ static void cpu_set(int fdtnode, u32 regval, void *info) > } > cpus[cpu] = regval; > > + /* set timebase frequency */ > + if (!tb_hz) { Instead of this condition, can't we tuck this DT parsing into the if (!read_common_info) block we already have? > + const struct fdt_property *prop; > + u32 *data; > + prop = fdt_get_property(dt_fdt(), fdtnode, > + "timebase-frequency", NULL); > + assert(prop != NULL); > + data = (u32 *)prop->data; > + tb_hz = fdt32_to_cpu(*data); > + } > + > /* set exception stack address for this CPU (in SPGR0) */ > > asm volatile ("mtsprg0 %[addr]" :: > -- > 2.5.5 > Otherwise looks good to me. Thanks, drew -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 16.08.2016 09:18, Suraj Jitindar Singh wrote: > It would be nice if we had a generic sleep function which could be used > in unit tests, add one. > > Add the variable tb_hz used to store the time base frequency which is read > from the device tree on setup. > > Add functions msleep, usleep and sleep in processor.c to sleep for a given > number of milliseconds, microseconds and time base ticks respectively. You finally called them mdelay, udelay and delay instead, so in case you respin, please adjust the commit message. > Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> > --- > > Change Log: > > V2 -> V3: > - Add patch to series > > Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> > --- > lib/powerpc/asm/processor.h | 19 +++++++++++++++++++ > lib/powerpc/asm/setup.h | 2 ++ > lib/powerpc/processor.c | 13 +++++++++++++ > lib/powerpc/setup.c | 12 ++++++++++++ > 4 files changed, 46 insertions(+) > > diff --git a/lib/powerpc/asm/processor.h b/lib/powerpc/asm/processor.h > index 09692bd..9554e08 100644 > --- a/lib/powerpc/asm/processor.h > +++ b/lib/powerpc/asm/processor.h > @@ -1,11 +1,30 @@ > #ifndef _ASMPOWERPC_PROCESSOR_H_ > #define _ASMPOWERPC_PROCESSOR_H_ > > +#include <libcflat.h> > #include <asm/ptrace.h> > > +#define cpu_relax() asm volatile ("" : : : "memory") I'd maybe add a "nop" instruction in there ... just in case? > #ifndef __ASSEMBLY__ > void handle_exception(int trap, void (*func)(struct pt_regs *, void *), void *); > void do_handle_exception(struct pt_regs *regs); > #endif /* __ASSEMBLY__ */ > > +static inline uint64_t get_tb(void) > +{ > + uint64_t tb; > + asm volatile ("mfspr %[tb],268" : [tb] "=r" (tb)); > + return tb; > +} > + > +extern void delay(uint64_t cycles); > +extern void udelay(uint64_t us); > + > +static inline void mdelay(uint64_t ms) > +{ > + while (ms--) > + udelay(1000); > +} > + > #endif /* _ASMPOWERPC_PROCESSOR_H_ */ > diff --git a/lib/powerpc/asm/setup.h b/lib/powerpc/asm/setup.h > index b1e1e5a..23b4156 100644 > --- a/lib/powerpc/asm/setup.h > +++ b/lib/powerpc/asm/setup.h > @@ -11,6 +11,8 @@ > extern u32 cpus[NR_CPUS]; > extern int nr_cpus; > > +extern uint64_t tb_hz; > + > #define NR_MEM_REGIONS 8 > #define MR_F_PRIMARY (1U << 0) > struct mem_region { > diff --git a/lib/powerpc/processor.c b/lib/powerpc/processor.c > index a78bc3c..c84bae5 100644 > --- a/lib/powerpc/processor.c > +++ b/lib/powerpc/processor.c > @@ -5,6 +5,7 @@ > #include <libcflat.h> > #include <asm/processor.h> > #include <asm/ptrace.h> > +#include <asm/setup.h> > > static struct { > void (*func)(struct pt_regs *, void *data); > @@ -36,3 +37,15 @@ void do_handle_exception(struct pt_regs *regs) > printf("unhandled cpu exception 0x%lx\n", regs->trap); > abort(); > } > + > +void delay(uint64_t cycles) > +{ > + uint64_t start = get_tb(); > + while((get_tb() - start) < cycles) > + cpu_relax(); Shouldn't there be some kind of wrap-around detection, like you had it in v2 for the decrementer based sleep function? > +} > + > +void udelay(uint64_t us) > +{ > + delay((us * tb_hz) / 1000000); > +} > diff --git a/lib/powerpc/setup.c b/lib/powerpc/setup.c > index e3d2afa..e7fa525 100644 > --- a/lib/powerpc/setup.c > +++ b/lib/powerpc/setup.c > @@ -24,6 +24,7 @@ extern void setup_args_progname(const char *args); > > u32 cpus[NR_CPUS] = { [0 ... NR_CPUS-1] = (~0U) }; > int nr_cpus; > +uint64_t tb_hz; > > struct mem_region mem_regions[NR_MEM_REGIONS]; > phys_addr_t __physical_start, __physical_end; > @@ -51,6 +52,17 @@ static void cpu_set(int fdtnode, u32 regval, void *info) > } > cpus[cpu] = regval; > > + /* set timebase frequency */ > + if (!tb_hz) { > + const struct fdt_property *prop; > + u32 *data; > + prop = fdt_get_property(dt_fdt(), fdtnode, > + "timebase-frequency", NULL); > + assert(prop != NULL); > + data = (u32 *)prop->data; > + tb_hz = fdt32_to_cpu(*data); You could short-cut that to fdt32_to_cpu(*(u32 *)prop->data) and get rid of the "data" variable. > + } > + > /* set exception stack address for this CPU (in SPGR0) */ > > asm volatile ("mtsprg0 %[addr]" :: > Thomas -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, 2016-08-16 at 14:41 +0200, Andrew Jones wrote: > On Tue, Aug 16, 2016 at 05:18:14PM +1000, Suraj Jitindar Singh wrote: > > > > It would be nice if we had a generic sleep function which could be > > used > > in unit tests, add one. > > > > Add the variable tb_hz used to store the time base frequency which > > is read > > from the device tree on setup. > > > > Add functions msleep, usleep and sleep in processor.c to sleep for > > a given > > number of milliseconds, microseconds and time base ticks > > respectively. > Above you talk about adding *sleep functions, but below you add > *delay > functions. Woops > > > > > > > Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> > > --- > > > > Change Log: > > > > V2 -> V3: > > - Add patch to series > > > > Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> > > --- > > lib/powerpc/asm/processor.h | 19 +++++++++++++++++++ > > lib/powerpc/asm/setup.h | 2 ++ > > lib/powerpc/processor.c | 13 +++++++++++++ > > lib/powerpc/setup.c | 12 ++++++++++++ > > 4 files changed, 46 insertions(+) > > > > diff --git a/lib/powerpc/asm/processor.h > > b/lib/powerpc/asm/processor.h > > index 09692bd..9554e08 100644 > > --- a/lib/powerpc/asm/processor.h > > +++ b/lib/powerpc/asm/processor.h > > @@ -1,11 +1,30 @@ > > #ifndef _ASMPOWERPC_PROCESSOR_H_ > > #define _ASMPOWERPC_PROCESSOR_H_ > > > > +#include <libcflat.h> > > #include <asm/ptrace.h> > > > > +#define cpu_relax() asm volatile ("" : : : "memory") > Please add this to lib/asm-generic/barrier.h, then > lib/ppc64/asm/barrier.h > will pick it up from there and you'll just need to make sure you > include > asm/barrier.h in processor.c Will do > > > > > + > > #ifndef __ASSEMBLY__ > > void handle_exception(int trap, void (*func)(struct pt_regs *, > > void *), void *); > > void do_handle_exception(struct pt_regs *regs); > > #endif /* __ASSEMBLY__ */ > > > > +static inline uint64_t get_tb(void) > > +{ > > + uint64_t tb; > > + asm volatile ("mfspr %[tb],268" : [tb] "=r" (tb)); > > + return tb; > > +} > > + > > +extern void delay(uint64_t cycles); > > +extern void udelay(uint64_t us); > > + > > +static inline void mdelay(uint64_t ms) > > +{ > > + while (ms--) > > + udelay(1000); > > +} > > + > > #endif /* _ASMPOWERPC_PROCESSOR_H_ */ > > diff --git a/lib/powerpc/asm/setup.h b/lib/powerpc/asm/setup.h > > index b1e1e5a..23b4156 100644 > > --- a/lib/powerpc/asm/setup.h > > +++ b/lib/powerpc/asm/setup.h > > @@ -11,6 +11,8 @@ > > extern u32 cpus[NR_CPUS]; > > extern int nr_cpus; > > > > +extern uint64_t tb_hz; > > + > > #define NR_MEM_REGIONS 8 > > #define MR_F_PRIMARY (1U << 0) > > struct mem_region { > > diff --git a/lib/powerpc/processor.c b/lib/powerpc/processor.c > > index a78bc3c..c84bae5 100644 > > --- a/lib/powerpc/processor.c > > +++ b/lib/powerpc/processor.c > > @@ -5,6 +5,7 @@ > > #include <libcflat.h> > > #include <asm/processor.h> > > #include <asm/ptrace.h> > > +#include <asm/setup.h> > > > > static struct { > > void (*func)(struct pt_regs *, void *data); > > @@ -36,3 +37,15 @@ void do_handle_exception(struct pt_regs *regs) > > printf("unhandled cpu exception 0x%lx\n", regs->trap); > > abort(); > > } > > + > > +void delay(uint64_t cycles) > > +{ > > + uint64_t start = get_tb(); > > + while((get_tb() - start) < cycles) > > + cpu_relax(); > > +} > > + > > +void udelay(uint64_t us) > > +{ > > + delay((us * tb_hz) / 1000000); > > +} > > diff --git a/lib/powerpc/setup.c b/lib/powerpc/setup.c > > index e3d2afa..e7fa525 100644 > > --- a/lib/powerpc/setup.c > > +++ b/lib/powerpc/setup.c > > @@ -24,6 +24,7 @@ extern void setup_args_progname(const char > > *args); > > > > u32 cpus[NR_CPUS] = { [0 ... NR_CPUS-1] = (~0U) }; > > int nr_cpus; > > +uint64_t tb_hz; > > > > struct mem_region mem_regions[NR_MEM_REGIONS]; > > phys_addr_t __physical_start, __physical_end; > > @@ -51,6 +52,17 @@ static void cpu_set(int fdtnode, u32 regval, > > void *info) > > } > > cpus[cpu] = regval; > > > > + /* set timebase frequency */ > > + if (!tb_hz) { > Instead of this condition, can't we tuck this DT parsing into the > if (!read_common_info) block we already have? Didn't read that properly to realise that block is only called once, I'll move it into there. > > > > > + const struct fdt_property *prop; > > + u32 *data; > > + prop = fdt_get_property(dt_fdt(), fdtnode, > > + "timebase-frequency", > > NULL); > > + assert(prop != NULL); > > + data = (u32 *)prop->data; > > + tb_hz = fdt32_to_cpu(*data); > > + } > > + > > /* set exception stack address for this CPU (in SPGR0) */ > > > > asm volatile ("mtsprg0 %[addr]" :: -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, 2016-08-16 at 14:54 +0200, Thomas Huth wrote: > On 16.08.2016 09:18, Suraj Jitindar Singh wrote: > > > > It would be nice if we had a generic sleep function which could be > > used > > in unit tests, add one. > > > > Add the variable tb_hz used to store the time base frequency which > > is read > > from the device tree on setup. > > > > Add functions msleep, usleep and sleep in processor.c to sleep for > > a given > > number of milliseconds, microseconds and time base ticks > > respectively. > You finally called them mdelay, udelay and delay instead, so in case > you > respin, please adjust the commit message. Woops, I'll fix those > > > > > Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> > > --- > > > > Change Log: > > > > V2 -> V3: > > - Add patch to series > > > > Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> > > --- > > lib/powerpc/asm/processor.h | 19 +++++++++++++++++++ > > lib/powerpc/asm/setup.h | 2 ++ > > lib/powerpc/processor.c | 13 +++++++++++++ > > lib/powerpc/setup.c | 12 ++++++++++++ > > 4 files changed, 46 insertions(+) > > > > diff --git a/lib/powerpc/asm/processor.h > > b/lib/powerpc/asm/processor.h > > index 09692bd..9554e08 100644 > > --- a/lib/powerpc/asm/processor.h > > +++ b/lib/powerpc/asm/processor.h > > @@ -1,11 +1,30 @@ > > #ifndef _ASMPOWERPC_PROCESSOR_H_ > > #define _ASMPOWERPC_PROCESSOR_H_ > > > > +#include <libcflat.h> > > #include <asm/ptrace.h> > > > > +#define cpu_relax() asm volatile ("" : : : "memory") > I'd maybe add a "nop" instruction in there ... just in case? We don't put the nop in anywhere else or in the kernel. I'm gonna leave this. > > > > > #ifndef __ASSEMBLY__ > > void handle_exception(int trap, void (*func)(struct pt_regs *, > > void *), void *); > > void do_handle_exception(struct pt_regs *regs); > > #endif /* __ASSEMBLY__ */ > > > > +static inline uint64_t get_tb(void) > > +{ > > + uint64_t tb; > > + asm volatile ("mfspr %[tb],268" : [tb] "=r" (tb)); > > + return tb; > > +} > > + > > +extern void delay(uint64_t cycles); > > +extern void udelay(uint64_t us); > > + > > +static inline void mdelay(uint64_t ms) > > +{ > > + while (ms--) > > + udelay(1000); > > +} > > + > > #endif /* _ASMPOWERPC_PROCESSOR_H_ */ > > diff --git a/lib/powerpc/asm/setup.h b/lib/powerpc/asm/setup.h > > index b1e1e5a..23b4156 100644 > > --- a/lib/powerpc/asm/setup.h > > +++ b/lib/powerpc/asm/setup.h > > @@ -11,6 +11,8 @@ > > extern u32 cpus[NR_CPUS]; > > extern int nr_cpus; > > > > +extern uint64_t tb_hz; > > + > > #define NR_MEM_REGIONS 8 > > #define MR_F_PRIMARY (1U << 0) > > struct mem_region { > > diff --git a/lib/powerpc/processor.c b/lib/powerpc/processor.c > > index a78bc3c..c84bae5 100644 > > --- a/lib/powerpc/processor.c > > +++ b/lib/powerpc/processor.c > > @@ -5,6 +5,7 @@ > > #include <libcflat.h> > > #include <asm/processor.h> > > #include <asm/ptrace.h> > > +#include <asm/setup.h> > > > > static struct { > > void (*func)(struct pt_regs *, void *data); > > @@ -36,3 +37,15 @@ void do_handle_exception(struct pt_regs *regs) > > printf("unhandled cpu exception 0x%lx\n", regs->trap); > > abort(); > > } > > + > > +void delay(uint64_t cycles) > > +{ > > + uint64_t start = get_tb(); > > + while((get_tb() - start) < cycles) > > + cpu_relax(); > Shouldn't there be some kind of wrap-around detection, like you had > it > in v2 for the decrementer based sleep function? Thanks for catching that, highly unlikely this will overflow (64-bit for timebase vs 31-bit for decrementer) but probably worth adding a check to be sure. > > > > > +} > > + > > +void udelay(uint64_t us) > > +{ > > + delay((us * tb_hz) / 1000000); > > +} > > diff --git a/lib/powerpc/setup.c b/lib/powerpc/setup.c > > index e3d2afa..e7fa525 100644 > > --- a/lib/powerpc/setup.c > > +++ b/lib/powerpc/setup.c > > @@ -24,6 +24,7 @@ extern void setup_args_progname(const char > > *args); > > > > u32 cpus[NR_CPUS] = { [0 ... NR_CPUS-1] = (~0U) }; > > int nr_cpus; > > +uint64_t tb_hz; > > > > struct mem_region mem_regions[NR_MEM_REGIONS]; > > phys_addr_t __physical_start, __physical_end; > > @@ -51,6 +52,17 @@ static void cpu_set(int fdtnode, u32 regval, > > void *info) > > } > > cpus[cpu] = regval; > > > > + /* set timebase frequency */ > > + if (!tb_hz) { > > + const struct fdt_property *prop; > > + u32 *data; > > + prop = fdt_get_property(dt_fdt(), fdtnode, > > + "timebase-frequency", > > NULL); > > + assert(prop != NULL); > > + data = (u32 *)prop->data; > > + tb_hz = fdt32_to_cpu(*data); > You could short-cut that to fdt32_to_cpu(*(u32 *)prop->data) and get > rid > of the "data" variable. Moved this into the code block below were those are both already defined. > > > > > + } > > + > > /* set exception stack address for this CPU (in SPGR0) */ > > > > asm volatile ("mtsprg0 %[addr]" :: > > > Thomas > -- To unsubscribe from this list: send the line "unsubscribe kvm" 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/lib/powerpc/asm/processor.h b/lib/powerpc/asm/processor.h index 09692bd..9554e08 100644 --- a/lib/powerpc/asm/processor.h +++ b/lib/powerpc/asm/processor.h @@ -1,11 +1,30 @@ #ifndef _ASMPOWERPC_PROCESSOR_H_ #define _ASMPOWERPC_PROCESSOR_H_ +#include <libcflat.h> #include <asm/ptrace.h> +#define cpu_relax() asm volatile ("" : : : "memory") + #ifndef __ASSEMBLY__ void handle_exception(int trap, void (*func)(struct pt_regs *, void *), void *); void do_handle_exception(struct pt_regs *regs); #endif /* __ASSEMBLY__ */ +static inline uint64_t get_tb(void) +{ + uint64_t tb; + asm volatile ("mfspr %[tb],268" : [tb] "=r" (tb)); + return tb; +} + +extern void delay(uint64_t cycles); +extern void udelay(uint64_t us); + +static inline void mdelay(uint64_t ms) +{ + while (ms--) + udelay(1000); +} + #endif /* _ASMPOWERPC_PROCESSOR_H_ */ diff --git a/lib/powerpc/asm/setup.h b/lib/powerpc/asm/setup.h index b1e1e5a..23b4156 100644 --- a/lib/powerpc/asm/setup.h +++ b/lib/powerpc/asm/setup.h @@ -11,6 +11,8 @@ extern u32 cpus[NR_CPUS]; extern int nr_cpus; +extern uint64_t tb_hz; + #define NR_MEM_REGIONS 8 #define MR_F_PRIMARY (1U << 0) struct mem_region { diff --git a/lib/powerpc/processor.c b/lib/powerpc/processor.c index a78bc3c..c84bae5 100644 --- a/lib/powerpc/processor.c +++ b/lib/powerpc/processor.c @@ -5,6 +5,7 @@ #include <libcflat.h> #include <asm/processor.h> #include <asm/ptrace.h> +#include <asm/setup.h> static struct { void (*func)(struct pt_regs *, void *data); @@ -36,3 +37,15 @@ void do_handle_exception(struct pt_regs *regs) printf("unhandled cpu exception 0x%lx\n", regs->trap); abort(); } + +void delay(uint64_t cycles) +{ + uint64_t start = get_tb(); + while((get_tb() - start) < cycles) + cpu_relax(); +} + +void udelay(uint64_t us) +{ + delay((us * tb_hz) / 1000000); +} diff --git a/lib/powerpc/setup.c b/lib/powerpc/setup.c index e3d2afa..e7fa525 100644 --- a/lib/powerpc/setup.c +++ b/lib/powerpc/setup.c @@ -24,6 +24,7 @@ extern void setup_args_progname(const char *args); u32 cpus[NR_CPUS] = { [0 ... NR_CPUS-1] = (~0U) }; int nr_cpus; +uint64_t tb_hz; struct mem_region mem_regions[NR_MEM_REGIONS]; phys_addr_t __physical_start, __physical_end; @@ -51,6 +52,17 @@ static void cpu_set(int fdtnode, u32 regval, void *info) } cpus[cpu] = regval; + /* set timebase frequency */ + if (!tb_hz) { + const struct fdt_property *prop; + u32 *data; + prop = fdt_get_property(dt_fdt(), fdtnode, + "timebase-frequency", NULL); + assert(prop != NULL); + data = (u32 *)prop->data; + tb_hz = fdt32_to_cpu(*data); + } + /* set exception stack address for this CPU (in SPGR0) */ asm volatile ("mtsprg0 %[addr]" ::