[PATCH v2 1/2] ARM: topology: Use a clock if possible to get the CPU frequency
From: Maxime Ripard <hidden>
Date: 2014-06-30 10:12:22
Also in:
linux-devicetree
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
Possibly related (same subject, not in this thread)
- 2014-07-08 · Re: [PATCH v2 1/2] ARM: topology: Use a clock if possible to get the CPU frequency · Maxime Ripard <hidden>
- 2014-07-04 · Re: [PATCH v2 1/2] ARM: topology: Use a clock if possible to get the CPU frequency · Vincent Guittot <hidden>
- 2014-07-04 · Re: [PATCH v2 1/2] ARM: topology: Use a clock if possible to get the CPU frequency · Maxime Ripard <hidden>
- 2014-07-03 · Re: [PATCH v2 1/2] ARM: topology: Use a clock if possible to get the CPU frequency · Vincent Guittot <hidden>
- 2014-07-03 · Re: [PATCH v2 1/2] ARM: topology: Use a clock if possible to get the CPU frequency · Maxime Ripard <hidden>
The Cortex-A7 and Cortex-A15 based SoCs need a clock-frequency property in the topology code. Allow to use a clock to provide the same information. Signed-off-by: Maxime Ripard <redacted> --- arch/arm/kernel/topology.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-)
diff --git a/arch/arm/kernel/topology.c b/arch/arm/kernel/topology.c
index 9d853189028b..268443d88094 100644
--- a/arch/arm/kernel/topology.c
+++ b/arch/arm/kernel/topology.c@@ -11,6 +11,7 @@ * for more details. */ +#include <linux/clk.h> #include <linux/cpu.h> #include <linux/cpumask.h> #include <linux/export.h>
@@ -100,8 +101,8 @@ static void __init parse_dt_topology(void) GFP_NOWAIT); for_each_possible_cpu(cpu) { - const u32 *rate; - int len; + struct clk *clk; + u32 rate = 0; /* too early to use cpu->of_node */ cn = of_get_cpu_node(cpu, NULL);
@@ -117,14 +118,24 @@ static void __init parse_dt_topology(void) if (cpu_eff->compatible == NULL) continue; - rate = of_get_property(cn, "clock-frequency", &len); - if (!rate || len != 4) { - pr_err("%s missing clock-frequency property\n", - cn->full_name); + clk = of_clk_get(cn, 0); + if (!IS_ERR(clk)) + rate = clk_get_rate(clk); + else + of_property_read_u32(cn, "clock-frequency", &rate); + + if (!rate) { + pr_err("%s missing clocks or clock-frequency properties\n", + cn->full_name); + continue; + } + + if (!rate) { + pr_err("%s invalid CPU frequency", cn->full_name); continue; } - capacity = ((be32_to_cpup(rate)) >> 20) * cpu_eff->efficiency; + capacity = ((rate) >> 20) * cpu_eff->efficiency; /* Save min capacity of the system */ if (capacity < min_capacity)
--
2.0.0