Re: [PATCH v2] clk: rockchip: disable unused clocks

Heiko Stübner
2014-10-30T18:46:41Z

Hi Kever,

Am Donnerstag, 30. Oktober 2014, 21:38:55 schrieb Kever Yang:
> The rockchip clock driver use CLK_IGNORE_UNUSED flag to make sure
> all the clocks are available like default power on state.
> We have implement the clock manage in most of rockchip drivers,
> it is time to remove it for power save.
> Instead we add CLK_IGNORE_UNUSED for some clock nodes which should
> be on during boot or no module driver in kernel will initialize it.
>
> Signed-off-by: Kever Yang <kever.yang@rock-chips.com>

I've tested this on all 3 currently supported Rockchip socs and was able to
boot to an initramfs on all of them.

[...]

> diff --git a/drivers/clk/rockchip/clk-rk3288.c
> b/drivers/clk/rockchip/clk-rk3288.c index 279a662..cf9d8b0 100644
> --- a/drivers/clk/rockchip/clk-rk3288.c
> +++ b/drivers/clk/rockchip/clk-rk3288.c

[...]

> - COMPOSITE_NOMUX(0, "armcore0", "armclk", 0,
> - RK3288_CLKSEL_CON(36), 0, 3, DFLAGS | CLK_DIVIDER_READ_ONLY,
> + COMPOSITE_NOMUX(0, "armcore0", "armclk", CLK_IGNORE_UNUSED,
> + RK3288_CLKSEL_CON(36), 0, 3, DFLAGS,
> RK3288_CLKGATE_CON(12), 0, GFLAGS),
> - COMPOSITE_NOMUX(0, "armcore1", "armclk", 0,
> - RK3288_CLKSEL_CON(36), 4, 3, DFLAGS | CLK_DIVIDER_READ_ONLY,
> + COMPOSITE_NOMUX(0, "armcore1", "armclk", CLK_IGNORE_UNUSED,
> + RK3288_CLKSEL_CON(36), 4, 3, DFLAGS,
> RK3288_CLKGATE_CON(12), 1, GFLAGS),
> - COMPOSITE_NOMUX(0, "armcore2", "armclk", 0,
> - RK3288_CLKSEL_CON(36), 8, 3, DFLAGS | CLK_DIVIDER_READ_ONLY,
> + COMPOSITE_NOMUX(0, "armcore2", "armclk", CLK_IGNORE_UNUSED,
> + RK3288_CLKSEL_CON(36), 8, 3, DFLAGS,
> RK3288_CLKGATE_CON(12), 2, GFLAGS),
> - COMPOSITE_NOMUX(0, "armcore3", "armclk", 0,
> - RK3288_CLKSEL_CON(36), 12, 3, DFLAGS | CLK_DIVIDER_READ_ONLY,
> + COMPOSITE_NOMUX(0, "armcore3", "armclk", CLK_IGNORE_UNUSED,
> + RK3288_CLKSEL_CON(36), 12, 3, DFLAGS,
> RK3288_CLKGATE_CON(12), 3, GFLAGS),
> - COMPOSITE_NOMUX(0, "l2ram", "armclk", 0,
> - RK3288_CLKSEL_CON(37), 0, 3, DFLAGS | CLK_DIVIDER_READ_ONLY,
> + COMPOSITE_NOMUX(0, "l2ram", "armclk", CLK_IGNORE_UNUSED,
> + RK3288_CLKSEL_CON(37), 0, 3, DFLAGS,
> RK3288_CLKGATE_CON(12), 4, GFLAGS),
> - COMPOSITE_NOMUX(0, "aclk_core_m0", "armclk", 0,
> - RK3288_CLKSEL_CON(0), 0, 4, DFLAGS | CLK_DIVIDER_READ_ONLY,
> + COMPOSITE_NOMUX(0, "aclk_core_m0", "armclk", CLK_IGNORE_UNUSED,
> + RK3288_CLKSEL_CON(0), 0, 4, DFLAGS,
> RK3288_CLKGATE_CON(12), 5, GFLAGS),
> - COMPOSITE_NOMUX(0, "aclk_core_mp", "armclk", 0,
> - RK3288_CLKSEL_CON(0), 4, 4, DFLAGS | CLK_DIVIDER_READ_ONLY,
> + COMPOSITE_NOMUX(0, "aclk_core_mp", "armclk", CLK_IGNORE_UNUSED,
> + RK3288_CLKSEL_CON(0), 4, 4, DFLAGS,
> RK3288_CLKGATE_CON(12), 6, GFLAGS),
> COMPOSITE_NOMUX(0, "atclk", "armclk", 0,
> RK3288_CLKSEL_CON(37), 4, 5, DFLAGS | CLK_DIVIDER_READ_ONLY,

For these clocks you're removing the READ_ONLY dvider-flags. If this is
necessary for something it should be a separate patch.
In this change it is nevertheless unrelated.

Heiko