On Mon, Feb 21, 2022 at 03:26:18PM +0800, Edwin Chiu wrote:
> Create cpuidle driver for sunplus sp7021 chip
>
> Signed-off-by: Edwin Chiu <edwinchiu0505tw@xxxxxxxxx>
> ---
> Changes in v3
> - Rearrangement #include sequence
> - Change remark style to /*~*/
> - Align author email address to same as sob
> - Optimal code
> Changes in v4
> - According Rob Herringrobh's comment
> There is no need for this binding.
> Just wanting a different driver is not a reason
> for a duplicate schema.
> So remove yaml file and submit driver again.
> Changes in v5
> - According Krzysztof's comment
> You either use appropriate compatible in DT
> or add your compatible to cpuidle-arm.
> Even if this did not work, then the solution is to
> use common parts, not to duplicate entire driver.
> According Sudeep's comment
> In short NACK for any dedicated driver for this platform,
> use the generic cpuidle-arm driver with appropriate platform hooks
> Create cpuidle-sunplus.c in arch/arm/mach-sunplus/
> for hook generic cpuidle-arm driver
>
> MAINTAINERS | 6 ++
> arch/arm/mach-sunplus/cpuidle-sunplus.c | 88 +++++++++++++++++
> include/linux/platform_data/cpuidle-sunplus.h | 12 ++++
> 3 files changed, 106 insertions(+)
> create mode 100644 arch/arm/mach-sunplus/cpuidle-sunplus.c
> create mode 100644 include/linux/platform_data/cpuidle-sunplus.h
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e0dca8f..5c96428 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -18252,6 +18252,12 @@ L: netdev@xxxxxxxxxxxxxxx
> S: Maintained
> F: drivers/net/ethernet/dlink/sundance.c
>
> +SUNPLUS CPUIDLE DRIVER
> +M: Edwin Chiu <edwinchiu0505tw@xxxxxxxxx>
> +S: Maintained
> +F: arch/arm/mach-sunplus/cpuidle-sunplus.c
> +F: include/linux/platform_data/cpuidle-sunplus.h
> +
> SUPERH
> M: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
> M: Rich Felker <dalias@xxxxxxxx>
> diff --git a/arch/arm/mach-sunplus/cpuidle-sunplus.c b/arch/arm/mach-sunplus/cpuidle-sunplus.c
> new file mode 100644
> index 0000000..e9d9738
> --- /dev/null
> +++ b/arch/arm/mach-sunplus/cpuidle-sunplus.c
> @@ -0,0 +1,88 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * SP7021 cpu idle Driver.
> + * Copyright (C) Sunplus Tech / Tibbo Tech.
> + */
> +#define pr_fmt(fmt) "CPUidle arm: " fmt
> +
> +#include <linux/cpuidle.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_data/cpuidle-sunplus.h>
> +
> +#include <asm/cpuidle.h>
> +
> +typedef int (*idle_fn)(void);
> +
> +static DEFINE_PER_CPU(idle_fn*, sp7021_idle_ops);
> +
> +static int sp7021_cpuidle_enter(unsigned long index)
> +{
> + return __this_cpu_read(sp7021_idle_ops)[index]();
> +}
> +static int sp7021_cpu_spc(void)
> +{
> + cpu_v7_do_idle(); /* idle to WFI */
> + return 0;
> +}
You really don't need a cpuidle driver to just WFI for any states.
Add the driver when you have something non WFI in the suspend function.
> +static const struct of_device_id sp7021_idle_state_match[] = {
> + { .compatible = "arm,idle-state", .data = sp7021_cpu_spc },
> + { },
> +};
This is better than adding new driver like you did in previous version.
I did a quick check but couldn't figure out. How do cpus get switched
ON or OFF on this platform(for example during CPU hotplug) ?
--
Regards,
Sudeep
