Re: [PATCH] clk: rockchip: add initcall to set clk defaults after syscons are available

Kever Yang
2014-09-22T07:56:22Z

Heiko,

On 08/07/2014 08:57 PM, Heiko Stübner wrote:
> PLLs on Rockchip platforms report their locking state in an external
> register situated in the "General Register Files" which is provided
> through a syscon device.
>
> When the initial clk init runs, this syscon is of course not yet
> available, making it impossible to set PLLs to other frequencies
> through the assigned-rate property of the clock-controller node.
>
> Syscon devices are initialized through a postcore initcall, so add an
> arch_initcall to rerun the rockchip specific clock initalization when
> the GRF is available.
>
> As the clock init already runs two times (through of_clk_add_provider
> and of_clk_init), a third time shouldn't hurt to much and in the best
> case wouldn't change any settings at all.
>
> Signed-off-by: Heiko Stuebner <heiko@sntech.de>
> ---
> drivers/clk/rockchip/clk.c | 13 +++++++++++++
> 1 file changed, 13 insertions(+)
>
> diff --git a/drivers/clk/rockchip/clk.c b/drivers/clk/rockchip/clk.c
> index 9a3adb1..e14b108 100644
> --- a/drivers/clk/rockchip/clk.c
> +++ b/drivers/clk/rockchip/clk.c
> @@ -23,6 +23,7 @@
> #include <linux/slab.h>
> #include <linux/clk.h>
> #include <linux/clk-provider.h>
> +#include <linux/clk/clk-conf.h>
> #include <linux/mfd/syscon.h>
> #include <linux/regmap.h>
> #include "clk.h"
> @@ -126,6 +127,18 @@ void __init rockchip_clk_init(struct device_node *np, void __iomem *base,
> of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
> }
>
> +/**
> + * Set clock-defaults again, after grf regmap is available for PLLs.
> + */
> +static int __init rockchip_clk_set_defaults(void)
> +{
> + if (cru_node)
> + return of_clk_set_defaults(cru_node, true);
> +
> + return 0;
> +}
> +arch_initcall(rockchip_clk_set_defaults);
> +
> struct regmap *rockchip_clk_get_grf(void)
> {
> if (IS_ERR(grf))
This patch works on my rk3288 evb, so,
Tested-by: Kever Yang <kever.yang@rock-chips.com>