On Tuesday, May 27, 2014 05:20:53 PM Viresh Kumar wrote:
Drivers expecting CPU's OPPs from device tree initialize OPP table themselves by calling of_init_opp_table() and there is nothing driver specific in that. They all do it in the same redundant way.
It would be better if we can get rid of redundancy by initializing CPU OPPs from CPU core code for all CPUs (that have a "operating-points" property defined in their node).
This patch calls of_init_opp_table() right after CPU device is registered in register_cpu(). of_init_opp_table() also has a dummy implementation which simply returns -ENOSYS when CONFIG_OPP or CONFIG_OF isn't supported by some platform.
Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: Amit Daniel Kachhap amit.daniel@samsung.com Cc: Kukjin Kim kgene.kim@samsung.com Cc: Shawn Guo shawn.guo@linaro.org Cc: Sudeep Holla sudeep.holla@arm.com Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
drivers/base/cpu.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 006b1bc..790183f 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -16,6 +16,7 @@ #include <linux/acpi.h> #include <linux/of.h> #include <linux/cpufeature.h> +#include <linux/pm_opp.h> #include "base.h" @@ -349,10 +350,12 @@ int register_cpu(struct cpu *cpu, int num) if (cpu->hotpluggable) cpu->dev.groups = hotplugable_cpu_attr_groups; error = device_register(&cpu->dev);
- if (!error)
per_cpu(cpu_sys_devices, num) = &cpu->dev;- if (!error)
register_cpu_under_node(num, cpu_to_node(num));
- if (error)
return error;- per_cpu(cpu_sys_devices, num) = &cpu->dev;
- register_cpu_under_node(num, cpu_to_node(num));
- of_init_opp_table(&cpu->dev);
Having thought a bit more about that I don't really like this.
In the ACPI land we have a processor driver that binds to CPU devices and carries out similar initialization. I kind of prefer that to littering core code with platform-specific stuff.
Rafael