diff options
| author | Pavankumar Kondeti <pkondeti@codeaurora.org> | 2015-05-07 17:14:48 +0530 |
|---|---|---|
| committer | Pavankumar Kondeti <pkondeti@codeaurora.org> | 2016-09-30 12:29:19 +0530 |
| commit | e91d6ecf73e9866337787bee54afbbfdbd7d9094 (patch) | |
| tree | 4b00adba4d2c9a0bb6fb3d67536697d69ef1166c /arch | |
| parent | 4ac03df1e16b160b0630c38661eb7fc19e324912 (diff) | |
arm: topology: Allow specifying the CPU efficiency from device tree
The efficiency of a CPU can vary across SoCs depending on the cache size,
bus interconnect frequencies etc. Allow specifying this from the device
tree. This value overrides the default values hardcoded in the efficiency
table.
Change-Id: If2885675ce3d7b43c3b2568fe1e29a76f48a5c3d
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/kernel/topology.c | 27 |
1 files changed, 20 insertions, 7 deletions
diff --git a/arch/arm/kernel/topology.c b/arch/arm/kernel/topology.c index 9e7ed5c322f4..e683d147816c 100644 --- a/arch/arm/kernel/topology.c +++ b/arch/arm/kernel/topology.c @@ -273,6 +273,7 @@ static int __init parse_dt_topology(void) for_each_possible_cpu(cpu) { const u32 *rate; int len; + u32 efficiency; /* too early to use cpu->of_node */ cn = of_get_cpu_node(cpu, NULL); @@ -281,14 +282,26 @@ static int __init parse_dt_topology(void) continue; } - for (cpu_eff = table_efficiency; cpu_eff->compatible; cpu_eff++) - if (of_device_is_compatible(cn, cpu_eff->compatible)) - break; + /* + * The CPU efficiency value passed from the device tree + * overrides the value defined in the table_efficiency[] + */ + if (of_property_read_u32(cn, "efficiency", &efficiency) < 0) { - if (cpu_eff->compatible == NULL) - continue; + for (cpu_eff = table_efficiency; + cpu_eff->compatible; cpu_eff++) + + if (of_device_is_compatible(cn, + cpu_eff->compatible)) + break; + + if (cpu_eff->compatible == NULL) + continue; + + efficiency = cpu_eff->efficiency; + } - per_cpu(cpu_efficiency, cpu) = cpu_eff->efficiency; + per_cpu(cpu_efficiency, cpu) = efficiency; rate = of_get_property(cn, "clock-frequency", &len); if (!rate || len != 4) { @@ -297,7 +310,7 @@ static int __init parse_dt_topology(void) continue; } - capacity = ((be32_to_cpup(rate)) >> 20) * cpu_eff->efficiency; + capacity = ((be32_to_cpup(rate)) >> 20) * efficiency; /* Save min capacity of the system */ if (capacity < min_capacity) |