Mark Rutland <mark.rutland@xxxxxxx> writes: > On Wed, Oct 07, 2015 at 08:22:40PM +0800, Dawei Chien wrote: >> From: "Dawei.Chien" <dawei.chien@xxxxxxxxxxxx> >> >> This power model is base on Intelligent Power Allocation (IPA) technical, >> requires that the operating-points of the CPUs are registered using the >> kernel's opp library and the `cpufreq_frequency_table` is assigned to the >> `struct device` of the cpu MT8173. >> >> Signed-off-by: Dawei.Chien <dawei.chien@xxxxxxxxxxxx> >> --- >> This patch is base on >> https://patchwork.kernel.org/patch/7034601/ >> --- >> drivers/cpufreq/mt8173-cpufreq.c | 97 +++++++++++++++++++++++++++++++++----- >> 1 file changed, 86 insertions(+), 11 deletions(-) >> >> diff --git a/drivers/cpufreq/mt8173-cpufreq.c b/drivers/cpufreq/mt8173-cpufreq.c >> index 49caed2..9233ec5 100644 >> --- a/drivers/cpufreq/mt8173-cpufreq.c >> +++ b/drivers/cpufreq/mt8173-cpufreq.c >> @@ -28,7 +28,8 @@ >> #define MAX_VOLT_SHIFT (200000) >> #define MAX_VOLT_LIMIT (1150000) >> #define VOLT_TOL (10000) >> - >> +#define CAPACITANCE_CA53 (263) >> +#define CAPACITANCE_CA57 (530) >> /* >> * The struct mtk_cpu_dvfs_info holds necessary information for doing CPU DVFS >> * on each CPU power/clock domain of Mediatek SoCs. Each CPU cluster in >> @@ -51,6 +52,72 @@ struct mtk_cpu_dvfs_info { >> bool need_voltage_tracking; >> }; >> >> +struct mtk_cpu_static_power { >> + unsigned long voltage; >> + unsigned int power; >> +}; >> + >> +/* measured by WA program. */ >> +static const struct mtk_cpu_static_power mtk_ca53_static_power[] = { >> + {859000, 43}, >> + {908000, 52}, >> + {983000, 86}, >> + {1009000, 123}, >> + {1028000, 138}, >> + {1083000, 172}, >> + {1109000, 180}, >> + {1125000, 192}, >> +}; >> + >> +/* measured by WA program. */ >> +static const struct mtk_cpu_static_power mtk_ca57_static_power[] = { >> + {828000, 72}, >> + {867000, 90}, >> + {927000, 156}, >> + {968000, 181}, >> + {1007000, 298}, >> + {1049000, 435}, >> + {1089000, 533}, >> + {1125000, 533}, >> +}; > > This should be described in the DT, rather than necessitating tonnes of > these tables in the kernel. The above table is a simplification that is tying the static power of a device to a voltage (indirectly via frequency for ease of indexing perhaps). We should definitely look at describing the static power model in the device tree - but it is not entirely clear what is the best model to use as basis for the device tree bindings. Static power consumption depends on a few different parameters (silicon process, voltage, temperature, etc.). The relationship between them maybe non-linear and not all of these maybe significant for a given platform. e.g., for Juno, we are using a regression based on voltage and temperature which was deemed close enough (very subjective tbh). On the other hand, dynamic power consumption is somewhat simpler and I have patches[0][1][2] enabling it's description in device tree. Your comments there would be very much appreciated. As for this patch, I hope it can be moved to using the device tree when the bindings for static power are agreed upon. Although sub-optimal, I can't see any other way forward for now. [0] http://thread.gmane.org/gmane.linux.kernel/2011466/focus=130373 [1] http://thread.gmane.org/gmane.linux.kernel/2011466/focus=2011465 [2] http://article.gmane.org/gmane.linux.drivers.sensors/37859 > > Mark. > -- > To unsubscribe from this list: send the line "unsubscribe linux-pm" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
