| Message ID | 1391166969-25845-7-git-send-email-agraf@suse.de |
|---|---|
| State | Superseded |
| Delegated to: | York Sun |
| Headers | show |
On Fri, 2014-01-31 at 12:16 +0100, Alexander Graf wrote: > The only thing we know in our PV machine through device tree is the clock > speed of the CPUs. Take that as CPU speed, system speed and ddr speed so that > we have some meaningful values there at all. > > The CPU speed is important because our timing loops get determined based on it. > > Signed-off-by: Alexander Graf <agraf@suse.de> > --- > arch/powerpc/cpu/mpc85xx/Makefile | 2 ++ > board/freescale/qemu-ppce500/qemu-ppce500.c | 43 +++++++++++++++++++++++++++ > 2 files changed, 45 insertions(+) > > diff --git a/arch/powerpc/cpu/mpc85xx/Makefile b/arch/powerpc/cpu/mpc85xx/Makefile > index ef7637a..4094785 100644 > --- a/arch/powerpc/cpu/mpc85xx/Makefile > +++ b/arch/powerpc/cpu/mpc85xx/Makefile > @@ -102,7 +102,9 @@ obj-y += cpu.o > obj-y += cpu_init.o > obj-y += cpu_init_early.o > obj-y += interrupts.o > +ifneq ($(CONFIG_QEMU_E500),y) > obj-y += speed.o > +endif > obj-y += tlb.o > obj-y += traps.o > > diff --git a/board/freescale/qemu-ppce500/qemu-ppce500.c b/board/freescale/qemu-ppce500/qemu-ppce500.c > index 5d4dd64..9e9d688 100644 > --- a/board/freescale/qemu-ppce500/qemu-ppce500.c > +++ b/board/freescale/qemu-ppce500/qemu-ppce500.c > @@ -407,3 +407,46 @@ void init_laws(void) > { > /* We don't emulate LAWs yet */ > } > + > +static uint32_t get_cpu_freq(void) > +{ > + const void *fdt = get_fdt(); > + int cpus_node = fdt_path_offset(fdt, "/cpus"); > + int cpu_node = fdt_first_subnode(fdt, cpus_node); > + return myfdt_one_cell(fdt, cpu_node, "clock-frequency", 0); > +} > + > +void get_sys_info(sys_info_t *sys_info) > +{ > + int freq = get_cpu_freq(); > + > + memset(sys_info, 0, sizeof(sys_info_t)); > + sys_info->freq_systembus = freq; > + sys_info->freq_ddrbus = freq; > + sys_info->freq_processor[0] = freq; > +} > + > +int get_clocks (void) > +{ > + sys_info_t sys_info; > + > + get_sys_info(&sys_info); > + > + gd->cpu_clk = sys_info.freq_processor[0]; > + gd->bus_clk = sys_info.freq_systembus; > + gd->mem_clk = sys_info.freq_ddrbus; > + gd->arch.lbc_clk = sys_info.freq_ddrbus; > + > + return 0; > +} This probably decreases the accuracy of the timebase frequency, since you'll be basing it on the CPU frequency rather than the bus frequency. If you're doing this, why not override get_tbclk() as well? -Scott
On 04.02.2014, at 03:52, Scott Wood <scottwood@freescale.com> wrote: > On Fri, 2014-01-31 at 12:16 +0100, Alexander Graf wrote: >> The only thing we know in our PV machine through device tree is the clock >> speed of the CPUs. Take that as CPU speed, system speed and ddr speed so that >> we have some meaningful values there at all. >> >> The CPU speed is important because our timing loops get determined based on it. >> >> Signed-off-by: Alexander Graf <agraf@suse.de> >> --- >> arch/powerpc/cpu/mpc85xx/Makefile | 2 ++ >> board/freescale/qemu-ppce500/qemu-ppce500.c | 43 +++++++++++++++++++++++++++ >> 2 files changed, 45 insertions(+) >> >> diff --git a/arch/powerpc/cpu/mpc85xx/Makefile b/arch/powerpc/cpu/mpc85xx/Makefile >> index ef7637a..4094785 100644 >> --- a/arch/powerpc/cpu/mpc85xx/Makefile >> +++ b/arch/powerpc/cpu/mpc85xx/Makefile >> @@ -102,7 +102,9 @@ obj-y += cpu.o >> obj-y += cpu_init.o >> obj-y += cpu_init_early.o >> obj-y += interrupts.o >> +ifneq ($(CONFIG_QEMU_E500),y) >> obj-y += speed.o >> +endif >> obj-y += tlb.o >> obj-y += traps.o >> >> diff --git a/board/freescale/qemu-ppce500/qemu-ppce500.c b/board/freescale/qemu-ppce500/qemu-ppce500.c >> index 5d4dd64..9e9d688 100644 >> --- a/board/freescale/qemu-ppce500/qemu-ppce500.c >> +++ b/board/freescale/qemu-ppce500/qemu-ppce500.c >> @@ -407,3 +407,46 @@ void init_laws(void) >> { >> /* We don't emulate LAWs yet */ >> } >> + >> +static uint32_t get_cpu_freq(void) >> +{ >> + const void *fdt = get_fdt(); >> + int cpus_node = fdt_path_offset(fdt, "/cpus"); >> + int cpu_node = fdt_first_subnode(fdt, cpus_node); >> + return myfdt_one_cell(fdt, cpu_node, "clock-frequency", 0); >> +} >> + >> +void get_sys_info(sys_info_t *sys_info) >> +{ >> + int freq = get_cpu_freq(); >> + >> + memset(sys_info, 0, sizeof(sys_info_t)); >> + sys_info->freq_systembus = freq; >> + sys_info->freq_ddrbus = freq; >> + sys_info->freq_processor[0] = freq; >> +} >> + >> +int get_clocks (void) >> +{ >> + sys_info_t sys_info; >> + >> + get_sys_info(&sys_info); >> + >> + gd->cpu_clk = sys_info.freq_processor[0]; >> + gd->bus_clk = sys_info.freq_systembus; >> + gd->mem_clk = sys_info.freq_ddrbus; >> + gd->arch.lbc_clk = sys_info.freq_ddrbus; >> + >> + return 0; >> +} > > This probably decreases the accuracy of the timebase frequency, since > you'll be basing it on the CPU frequency rather than the bus frequency. > > If you're doing this, why not override get_tbclk() as well? That one only uses variables I already control, no? unsigned long get_tbclk (void) { unsigned long tbclk_div = CONFIG_SYS_FSL_TBCLK_DIV; return (gd->bus_clk + (tbclk_div >> 1)) / tbclk_div; } Alex
On Thu, 2014-02-06 at 12:11 +0100, Alexander Graf wrote: > On 04.02.2014, at 03:52, Scott Wood <scottwood@freescale.com> wrote: > > > On Fri, 2014-01-31 at 12:16 +0100, Alexander Graf wrote: > >> The only thing we know in our PV machine through device tree is the clock > >> speed of the CPUs. Take that as CPU speed, system speed and ddr speed so that > >> we have some meaningful values there at all. > >> > >> The CPU speed is important because our timing loops get determined based on it. > >> > >> Signed-off-by: Alexander Graf <agraf@suse.de> > >> --- > >> arch/powerpc/cpu/mpc85xx/Makefile | 2 ++ > >> board/freescale/qemu-ppce500/qemu-ppce500.c | 43 +++++++++++++++++++++++++++ > >> 2 files changed, 45 insertions(+) > >> > >> diff --git a/arch/powerpc/cpu/mpc85xx/Makefile b/arch/powerpc/cpu/mpc85xx/Makefile > >> index ef7637a..4094785 100644 > >> --- a/arch/powerpc/cpu/mpc85xx/Makefile > >> +++ b/arch/powerpc/cpu/mpc85xx/Makefile > >> @@ -102,7 +102,9 @@ obj-y += cpu.o > >> obj-y += cpu_init.o > >> obj-y += cpu_init_early.o > >> obj-y += interrupts.o > >> +ifneq ($(CONFIG_QEMU_E500),y) > >> obj-y += speed.o > >> +endif > >> obj-y += tlb.o > >> obj-y += traps.o > >> > >> diff --git a/board/freescale/qemu-ppce500/qemu-ppce500.c b/board/freescale/qemu-ppce500/qemu-ppce500.c > >> index 5d4dd64..9e9d688 100644 > >> --- a/board/freescale/qemu-ppce500/qemu-ppce500.c > >> +++ b/board/freescale/qemu-ppce500/qemu-ppce500.c > >> @@ -407,3 +407,46 @@ void init_laws(void) > >> { > >> /* We don't emulate LAWs yet */ > >> } > >> + > >> +static uint32_t get_cpu_freq(void) > >> +{ > >> + const void *fdt = get_fdt(); > >> + int cpus_node = fdt_path_offset(fdt, "/cpus"); > >> + int cpu_node = fdt_first_subnode(fdt, cpus_node); > >> + return myfdt_one_cell(fdt, cpu_node, "clock-frequency", 0); > >> +} > >> + > >> +void get_sys_info(sys_info_t *sys_info) > >> +{ > >> + int freq = get_cpu_freq(); > >> + > >> + memset(sys_info, 0, sizeof(sys_info_t)); > >> + sys_info->freq_systembus = freq; > >> + sys_info->freq_ddrbus = freq; > >> + sys_info->freq_processor[0] = freq; > >> +} > >> + > >> +int get_clocks (void) > >> +{ > >> + sys_info_t sys_info; > >> + > >> + get_sys_info(&sys_info); > >> + > >> + gd->cpu_clk = sys_info.freq_processor[0]; > >> + gd->bus_clk = sys_info.freq_systembus; > >> + gd->mem_clk = sys_info.freq_ddrbus; > >> + gd->arch.lbc_clk = sys_info.freq_ddrbus; > >> + > >> + return 0; > >> +} > > > > This probably decreases the accuracy of the timebase frequency, since > > you'll be basing it on the CPU frequency rather than the bus frequency. > > > > If you're doing this, why not override get_tbclk() as well? > > That one only uses variables I already control, no? > > unsigned long get_tbclk (void) > { > unsigned long tbclk_div = CONFIG_SYS_FSL_TBCLK_DIV; > > return (gd->bus_clk + (tbclk_div >> 1)) / tbclk_div; > } What did you set CONFIG_SYS_FSL_TBCLK_DIV to? -Scott
On 07.02.2014, at 02:33, Scott Wood <scottwood@freescale.com> wrote: > On Thu, 2014-02-06 at 12:11 +0100, Alexander Graf wrote: >> On 04.02.2014, at 03:52, Scott Wood <scottwood@freescale.com> wrote: >> >>> On Fri, 2014-01-31 at 12:16 +0100, Alexander Graf wrote: >>>> The only thing we know in our PV machine through device tree is the clock >>>> speed of the CPUs. Take that as CPU speed, system speed and ddr speed so that >>>> we have some meaningful values there at all. >>>> >>>> The CPU speed is important because our timing loops get determined based on it. >>>> >>>> Signed-off-by: Alexander Graf <agraf@suse.de> >>>> --- >>>> arch/powerpc/cpu/mpc85xx/Makefile | 2 ++ >>>> board/freescale/qemu-ppce500/qemu-ppce500.c | 43 +++++++++++++++++++++++++++ >>>> 2 files changed, 45 insertions(+) >>>> >>>> diff --git a/arch/powerpc/cpu/mpc85xx/Makefile b/arch/powerpc/cpu/mpc85xx/Makefile >>>> index ef7637a..4094785 100644 >>>> --- a/arch/powerpc/cpu/mpc85xx/Makefile >>>> +++ b/arch/powerpc/cpu/mpc85xx/Makefile >>>> @@ -102,7 +102,9 @@ obj-y += cpu.o >>>> obj-y += cpu_init.o >>>> obj-y += cpu_init_early.o >>>> obj-y += interrupts.o >>>> +ifneq ($(CONFIG_QEMU_E500),y) >>>> obj-y += speed.o >>>> +endif >>>> obj-y += tlb.o >>>> obj-y += traps.o >>>> >>>> diff --git a/board/freescale/qemu-ppce500/qemu-ppce500.c b/board/freescale/qemu-ppce500/qemu-ppce500.c >>>> index 5d4dd64..9e9d688 100644 >>>> --- a/board/freescale/qemu-ppce500/qemu-ppce500.c >>>> +++ b/board/freescale/qemu-ppce500/qemu-ppce500.c >>>> @@ -407,3 +407,46 @@ void init_laws(void) >>>> { >>>> /* We don't emulate LAWs yet */ >>>> } >>>> + >>>> +static uint32_t get_cpu_freq(void) >>>> +{ >>>> + const void *fdt = get_fdt(); >>>> + int cpus_node = fdt_path_offset(fdt, "/cpus"); >>>> + int cpu_node = fdt_first_subnode(fdt, cpus_node); >>>> + return myfdt_one_cell(fdt, cpu_node, "clock-frequency", 0); >>>> +} >>>> + >>>> +void get_sys_info(sys_info_t *sys_info) >>>> +{ >>>> + int freq = get_cpu_freq(); >>>> + >>>> + memset(sys_info, 0, sizeof(sys_info_t)); >>>> + sys_info->freq_systembus = freq; >>>> + sys_info->freq_ddrbus = freq; >>>> + sys_info->freq_processor[0] = freq; >>>> +} >>>> + >>>> +int get_clocks (void) >>>> +{ >>>> + sys_info_t sys_info; >>>> + >>>> + get_sys_info(&sys_info); >>>> + >>>> + gd->cpu_clk = sys_info.freq_processor[0]; >>>> + gd->bus_clk = sys_info.freq_systembus; >>>> + gd->mem_clk = sys_info.freq_ddrbus; >>>> + gd->arch.lbc_clk = sys_info.freq_ddrbus; >>>> + >>>> + return 0; >>>> +} >>> >>> This probably decreases the accuracy of the timebase frequency, since >>> you'll be basing it on the CPU frequency rather than the bus frequency. >>> >>> If you're doing this, why not override get_tbclk() as well? >> >> That one only uses variables I already control, no? >> >> unsigned long get_tbclk (void) >> { >> unsigned long tbclk_div = CONFIG_SYS_FSL_TBCLK_DIV; >> >> return (gd->bus_clk + (tbclk_div >> 1)) / tbclk_div; >> } > > What did you set CONFIG_SYS_FSL_TBCLK_DIV to? Nothing which is why it's defaulting to 8. Alex
On Fri, 2014-02-07 at 12:50 +0100, Alexander Graf wrote: > On 07.02.2014, at 02:33, Scott Wood <scottwood@freescale.com> wrote: > > > On Thu, 2014-02-06 at 12:11 +0100, Alexander Graf wrote: > >> On 04.02.2014, at 03:52, Scott Wood <scottwood@freescale.com> wrote: > >> > >>> On Fri, 2014-01-31 at 12:16 +0100, Alexander Graf wrote: > >>>> The only thing we know in our PV machine through device tree is the clock > >>>> speed of the CPUs. Take that as CPU speed, system speed and ddr speed so that > >>>> we have some meaningful values there at all. > >>>> > >>>> The CPU speed is important because our timing loops get determined based on it. > >>>> > >>>> Signed-off-by: Alexander Graf <agraf@suse.de> > >>>> --- > >>>> arch/powerpc/cpu/mpc85xx/Makefile | 2 ++ > >>>> board/freescale/qemu-ppce500/qemu-ppce500.c | 43 +++++++++++++++++++++++++++ > >>>> 2 files changed, 45 insertions(+) > >>>> > >>>> diff --git a/arch/powerpc/cpu/mpc85xx/Makefile b/arch/powerpc/cpu/mpc85xx/Makefile > >>>> index ef7637a..4094785 100644 > >>>> --- a/arch/powerpc/cpu/mpc85xx/Makefile > >>>> +++ b/arch/powerpc/cpu/mpc85xx/Makefile > >>>> @@ -102,7 +102,9 @@ obj-y += cpu.o > >>>> obj-y += cpu_init.o > >>>> obj-y += cpu_init_early.o > >>>> obj-y += interrupts.o > >>>> +ifneq ($(CONFIG_QEMU_E500),y) > >>>> obj-y += speed.o > >>>> +endif > >>>> obj-y += tlb.o > >>>> obj-y += traps.o > >>>> > >>>> diff --git a/board/freescale/qemu-ppce500/qemu-ppce500.c b/board/freescale/qemu-ppce500/qemu-ppce500.c > >>>> index 5d4dd64..9e9d688 100644 > >>>> --- a/board/freescale/qemu-ppce500/qemu-ppce500.c > >>>> +++ b/board/freescale/qemu-ppce500/qemu-ppce500.c > >>>> @@ -407,3 +407,46 @@ void init_laws(void) > >>>> { > >>>> /* We don't emulate LAWs yet */ > >>>> } > >>>> + > >>>> +static uint32_t get_cpu_freq(void) > >>>> +{ > >>>> + const void *fdt = get_fdt(); > >>>> + int cpus_node = fdt_path_offset(fdt, "/cpus"); > >>>> + int cpu_node = fdt_first_subnode(fdt, cpus_node); > >>>> + return myfdt_one_cell(fdt, cpu_node, "clock-frequency", 0); > >>>> +} > >>>> + > >>>> +void get_sys_info(sys_info_t *sys_info) > >>>> +{ > >>>> + int freq = get_cpu_freq(); > >>>> + > >>>> + memset(sys_info, 0, sizeof(sys_info_t)); > >>>> + sys_info->freq_systembus = freq; > >>>> + sys_info->freq_ddrbus = freq; > >>>> + sys_info->freq_processor[0] = freq; > >>>> +} > >>>> + > >>>> +int get_clocks (void) > >>>> +{ > >>>> + sys_info_t sys_info; > >>>> + > >>>> + get_sys_info(&sys_info); > >>>> + > >>>> + gd->cpu_clk = sys_info.freq_processor[0]; > >>>> + gd->bus_clk = sys_info.freq_systembus; > >>>> + gd->mem_clk = sys_info.freq_ddrbus; > >>>> + gd->arch.lbc_clk = sys_info.freq_ddrbus; > >>>> + > >>>> + return 0; > >>>> +} > >>> > >>> This probably decreases the accuracy of the timebase frequency, since > >>> you'll be basing it on the CPU frequency rather than the bus frequency. > >>> > >>> If you're doing this, why not override get_tbclk() as well? > >> > >> That one only uses variables I already control, no? > >> > >> unsigned long get_tbclk (void) > >> { > >> unsigned long tbclk_div = CONFIG_SYS_FSL_TBCLK_DIV; > >> > >> return (gd->bus_clk + (tbclk_div >> 1)) / tbclk_div; > >> } > > > > What did you set CONFIG_SYS_FSL_TBCLK_DIV to? > > Nothing which is why it's defaulting to 8. Hence why I suggested overriding get_tbclk() rather than trying to fake up a divider (which could be difficult if the CPU clock is not a multiple of the bus clock). -Scott
diff --git a/arch/powerpc/cpu/mpc85xx/Makefile b/arch/powerpc/cpu/mpc85xx/Makefile index ef7637a..4094785 100644 --- a/arch/powerpc/cpu/mpc85xx/Makefile +++ b/arch/powerpc/cpu/mpc85xx/Makefile @@ -102,7 +102,9 @@ obj-y += cpu.o obj-y += cpu_init.o obj-y += cpu_init_early.o obj-y += interrupts.o +ifneq ($(CONFIG_QEMU_E500),y) obj-y += speed.o +endif obj-y += tlb.o obj-y += traps.o diff --git a/board/freescale/qemu-ppce500/qemu-ppce500.c b/board/freescale/qemu-ppce500/qemu-ppce500.c index 5d4dd64..9e9d688 100644 --- a/board/freescale/qemu-ppce500/qemu-ppce500.c +++ b/board/freescale/qemu-ppce500/qemu-ppce500.c @@ -407,3 +407,46 @@ void init_laws(void) { /* We don't emulate LAWs yet */ } + +static uint32_t get_cpu_freq(void) +{ + const void *fdt = get_fdt(); + int cpus_node = fdt_path_offset(fdt, "/cpus"); + int cpu_node = fdt_first_subnode(fdt, cpus_node); + return myfdt_one_cell(fdt, cpu_node, "clock-frequency", 0); +} + +void get_sys_info(sys_info_t *sys_info) +{ + int freq = get_cpu_freq(); + + memset(sys_info, 0, sizeof(sys_info_t)); + sys_info->freq_systembus = freq; + sys_info->freq_ddrbus = freq; + sys_info->freq_processor[0] = freq; +} + +int get_clocks (void) +{ + sys_info_t sys_info; + + get_sys_info(&sys_info); + + gd->cpu_clk = sys_info.freq_processor[0]; + gd->bus_clk = sys_info.freq_systembus; + gd->mem_clk = sys_info.freq_ddrbus; + gd->arch.lbc_clk = sys_info.freq_ddrbus; + + return 0; +} + +/******************************************** + * get_bus_freq + * return system bus freq in Hz + *********************************************/ +ulong get_bus_freq (ulong dummy) +{ + sys_info_t sys_info; + get_sys_info(&sys_info); + return sys_info.freq_systembus; +}
The only thing we know in our PV machine through device tree is the clock speed of the CPUs. Take that as CPU speed, system speed and ddr speed so that we have some meaningful values there at all. The CPU speed is important because our timing loops get determined based on it. Signed-off-by: Alexander Graf <agraf@suse.de> --- arch/powerpc/cpu/mpc85xx/Makefile | 2 ++ board/freescale/qemu-ppce500/qemu-ppce500.c | 43 +++++++++++++++++++++++++++ 2 files changed, 45 insertions(+)