On Thu, 2014-02-06 at 12:11 +0100, Alexander Graf wrote: > On 04.02.2014, at 03:52, Scott Wood <scottw...@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 <ag...@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 _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot