[PATCH 1/1] clk: meson: gxbb: remove the "cpu_clk" from the GXBB and GXL driver

Jerome Brunet jbrunet at baylibre.com
Sun Apr 2 08:57:45 PDT 2017


On Sat, 2017-04-01 at 14:55 +0200, Martin Blumenstingl wrote:
> It seems that the "cpu_clk" was carried over from the meson8b clock
> controller driver. On Meson GX (GXBB/GXL/GXM) the registers which are
> used by the cpu_clk have a different purpose (in other words: they don't
> control the CPU clock anymore). HHI_SYS_CPU_CLK_CNTL1 bits 31:24 are
> reserved according to the public S905 datasheet, while bit 23 is the
> "A53_trace_clk_DIS" gate (which according to the datasheet should only
> be used in case a silicon bug is discovered) and bits 22:20 are a
> divider (A53_trace_clk). The meson clk-cpu code however expects that
> bits 28:20 are reserved for a divider (according to the public S805
> datasheet this "SCALE_DIV: This value represents an N+1 divider of the
> input clock.").
> 
> The CPU clock on Meson GX SoCs is provided by the SCPI DVFS clock
> driver instead. Two examples from a Meson GXL S905X SoC:
> - vcpu (SCPI DVFS clock 0) rate: 1000000000 / cpu_clk rate: 708000000
> - vcpu (SCPI DVFS clock 0) rate: 1512000000 / cpu_clk rate: 708000000
> 
> Unfortunately the CLKID_CPUCLK was already exported (but is currently
> not used) to DT. Due to the removal of this clock definition there is
> now a hole in the clk_hw_onecell_data (which is not a problem because
> this case is already handled in gxbb_clkc_probe).
> 
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl at googlemail.com>

Looks good to me.
I'll wait for the Ack of one of the DT maintainers to apply it.
Thx Martin

Cheers

> ---
>  drivers/clk/meson/gxbb.c              | 64 ++------------------------------
> ---
>  drivers/clk/meson/gxbb.h              |  2 +-
>  include/dt-bindings/clock/gxbb-clkc.h |  1 -
>  3 files changed, 4 insertions(+), 63 deletions(-)
> 
> diff --git a/drivers/clk/meson/gxbb.c b/drivers/clk/meson/gxbb.c
> index ad5f027af1a2..7cf88ca9bdce 100644
> --- a/drivers/clk/meson/gxbb.c
> +++ b/drivers/clk/meson/gxbb.c
> @@ -278,20 +278,6 @@ static const struct pll_rate_table
> gxl_gp0_pll_rate_table[] = {
>  	{ /* sentinel */ },
>  };
>  
> -static const struct clk_div_table cpu_div_table[] = {
> -	{ .val = 1, .div = 1 },
> -	{ .val = 2, .div = 2 },
> -	{ .val = 3, .div = 3 },
> -	{ .val = 2, .div = 4 },
> -	{ .val = 3, .div = 6 },
> -	{ .val = 4, .div = 8 },
> -	{ .val = 5, .div = 10 },
> -	{ .val = 6, .div = 12 },
> -	{ .val = 7, .div = 14 },
> -	{ .val = 8, .div = 16 },
> -	{ /* sentinel */ },
> -};
> -
>  static struct meson_clk_pll gxbb_fixed_pll = {
>  	.m = {
>  		.reg_off = HHI_MPLL_CNTL,
> @@ -612,21 +598,10 @@ static struct meson_clk_mpll gxbb_mpll2 = {
>  };
>  
>  /*
> - * FIXME cpu clocks and the legacy composite clocks (e.g. clk81) are both PLL
> - * post-dividers and should be modeled with their respective PLLs via the
> - * forthcoming coordinated clock rates feature
> + * FIXME The legacy composite clocks (e.g. clk81) are both PLL post-dividers
> + * and should be modeled with their respective PLLs via the forthcoming
> + * coordinated clock rates feature
>   */
> -static struct meson_clk_cpu gxbb_cpu_clk = {
> -	.reg_off = HHI_SYS_CPU_CLK_CNTL1,
> -	.div_table = cpu_div_table,
> -	.clk_nb.notifier_call = meson_clk_cpu_notifier_cb,
> -	.hw.init = &(struct clk_init_data){
> -		.name = "cpu_clk",
> -		.ops = &meson_clk_cpu_ops,
> -		.parent_names = (const char *[]){ "sys_pll" },
> -		.num_parents = 1,
> -	},
> -};
>  
>  static u32 mux_table_clk81[]	= { 6, 5, 7 };
>  
> @@ -1045,7 +1020,6 @@ static MESON_GATE(gxbb_ao_i2c, HHI_GCLK_AO, 4);
>  static struct clk_hw_onecell_data gxbb_hw_onecell_data = {
>  	.hws = {
>  		[CLKID_SYS_PLL]		    = &gxbb_sys_pll.hw,
> -		[CLKID_CPUCLK]		    = &gxbb_cpu_clk.hw,
>  		[CLKID_HDMI_PLL]	    = &gxbb_hdmi_pll.hw,
>  		[CLKID_FIXED_PLL]	    = &gxbb_fixed_pll.hw,
>  		[CLKID_FCLK_DIV2]	    = &gxbb_fclk_div2.hw,
> @@ -1165,7 +1139,6 @@ static struct clk_hw_onecell_data gxbb_hw_onecell_data =
> {
>  static struct clk_hw_onecell_data gxl_hw_onecell_data = {
>  	.hws = {
>  		[CLKID_SYS_PLL]		    = &gxbb_sys_pll.hw,
> -		[CLKID_CPUCLK]		    = &gxbb_cpu_clk.hw,
>  		[CLKID_HDMI_PLL]	    = &gxbb_hdmi_pll.hw,
>  		[CLKID_FIXED_PLL]	    = &gxbb_fixed_pll.hw,
>  		[CLKID_FCLK_DIV2]	    = &gxbb_fclk_div2.hw,
> @@ -1430,7 +1403,6 @@ struct clkc_data {
>  	unsigned int clk_dividers_count;
>  	struct meson_clk_audio_divider *const *clk_audio_dividers;
>  	unsigned int clk_audio_dividers_count;
> -	struct meson_clk_cpu *cpu_clk;
>  	struct clk_hw_onecell_data *hw_onecell_data;
>  };
>  
> @@ -1447,7 +1419,6 @@ static const struct clkc_data gxbb_clkc_data = {
>  	.clk_dividers_count = ARRAY_SIZE(gxbb_clk_dividers),
>  	.clk_audio_dividers = gxbb_audio_dividers,
>  	.clk_audio_dividers_count = ARRAY_SIZE(gxbb_audio_dividers),
> -	.cpu_clk = &gxbb_cpu_clk,
>  	.hw_onecell_data = &gxbb_hw_onecell_data,
>  };
>  
> @@ -1464,7 +1435,6 @@ static const struct clkc_data gxl_clkc_data = {
>  	.clk_dividers_count = ARRAY_SIZE(gxbb_clk_dividers),
>  	.clk_audio_dividers = gxbb_audio_dividers,
>  	.clk_audio_dividers_count = ARRAY_SIZE(gxbb_audio_dividers),
> -	.cpu_clk = &gxbb_cpu_clk,
>  	.hw_onecell_data = &gxl_hw_onecell_data,
>  };
>  
> @@ -1479,8 +1449,6 @@ static int gxbb_clkc_probe(struct platform_device *pdev)
>  	const struct clkc_data *clkc_data;
>  	void __iomem *clk_base;
>  	int ret, clkid, i;
> -	struct clk_hw *parent_hw;
> -	struct clk *parent_clk;
>  	struct device *dev = &pdev->dev;
>  
>  	clkc_data = of_device_get_match_data(&pdev->dev);
> @@ -1502,9 +1470,6 @@ static int gxbb_clkc_probe(struct platform_device *pdev)
>  	for (i = 0; i < clkc_data->clk_mplls_count; i++)
>  		clkc_data->clk_mplls[i]->base = clk_base;
>  
> -	/* Populate the base address for CPU clk */
> -	clkc_data->cpu_clk->base = clk_base;
> -
>  	/* Populate base address for gates */
>  	for (i = 0; i < clkc_data->clk_gates_count; i++)
>  		clkc_data->clk_gates[i]->reg = clk_base +
> @@ -1538,29 +1503,6 @@ static int gxbb_clkc_probe(struct platform_device
> *pdev)
>  			goto iounmap;
>  	}
>  
> -	/*
> -	 * Register CPU clk notifier
> -	 *
> -	 * FIXME this is wrong for a lot of reasons. First, the muxes should
> be
> -	 * struct clk_hw objects. Second, we shouldn't program the muxes in
> -	 * notifier handlers. The tricky programming sequence will be handled
> -	 * by the forthcoming coordinated clock rates mechanism once that
> -	 * feature is released.
> -	 *
> -	 * Furthermore, looking up the parent this way is terrible. At some
> -	 * point we will stop allocating a default struct clk when
> registering
> -	 * a new clk_hw, and this hack will no longer work. Releasing the ccr
> -	 * feature before that time solves the problem :-)
> -	 */
> -	parent_hw = clk_hw_get_parent(&clkc_data->cpu_clk->hw);
> -	parent_clk = parent_hw->clk;
> -	ret = clk_notifier_register(parent_clk, &clkc_data->cpu_clk->clk_nb);
> -	if (ret) {
> -		pr_err("%s: failed to register clock notifier for cpu_clk\n",
> -				__func__);
> -		goto iounmap;
> -	}
> -
>  	return of_clk_add_hw_provider(dev->of_node, of_clk_hw_onecell_get,
>  			clkc_data->hw_onecell_data);
>  
> diff --git a/drivers/clk/meson/gxbb.h b/drivers/clk/meson/gxbb.h
> index 17c6aef033ff..36330c2d4433 100644
> --- a/drivers/clk/meson/gxbb.h
> +++ b/drivers/clk/meson/gxbb.h
> @@ -171,7 +171,7 @@
>   * to be exposed to client nodes in DT: include/dt-bindings/clock/gxbb-clkc.h
>   */
>  #define CLKID_SYS_PLL		  0
> -/* CLKID_CPUCLK */
> +/* ID 1 is unused (it was used by the non-existing CLKID_CPUCLK before) */
>  /* CLKID_HDMI_PLL */
>  #define CLKID_FIXED_PLL		  3
>  /* CLKID_FCLK_DIV2 */
> diff --git a/include/dt-bindings/clock/gxbb-clkc.h b/include/dt-
> bindings/clock/gxbb-clkc.h
> index 4516bc4253b5..54faf83a4851 100644
> --- a/include/dt-bindings/clock/gxbb-clkc.h
> +++ b/include/dt-bindings/clock/gxbb-clkc.h
> @@ -5,7 +5,6 @@
>  #ifndef __GXBB_CLKC_H
>  #define __GXBB_CLKC_H
>  
> -#define CLKID_CPUCLK		1
>  #define CLKID_HDMI_PLL		2
>  #define CLKID_FCLK_DIV2		4
>  #define CLKID_FCLK_DIV3		5



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