Patchwork [v2,05/11] clk: sunxi: add PLL5 and PLL6 support

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Submitter Emilio López
Date Dec. 18, 2013, 12:44 a.m.
Message ID <1387327503-15651-6-git-send-email-emilio@elopez.com.ar>
Download mbox | patch
Permalink /patch/302609/
State New
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Comments

Emilio López - Dec. 18, 2013, 12:44 a.m.
This commit implements PLL5 and PLL6 support on the sunxi clock driver.
These PLLs use a similar factor clock, but differ on their outputs.

Signed-off-by: Emilio López <emilio@elopez.com.ar>
---
 Documentation/devicetree/bindings/clock/sunxi.txt |   2 +
 drivers/clk/sunxi/clk-sunxi.c                     | 230 ++++++++++++++++++++++
 2 files changed, 232 insertions(+)
Mike Turquette - Dec. 19, 2013, 4:59 a.m.
Quoting Emilio López (2013-12-17 16:44:57)
> +/**
> + * sunxi_divs_clk_setup() - Setup function for leaf divisors on clocks
> + *
> + * These clocks look something like this
> + *            ________________________
> + *           |         ___divisor 1---|----> to consumer
> + * parent >--|  pll___/___divisor 2---|----> to consumer
> + *           |        \_______________|____> to consumer
> + *           |________________________|
> + */

+1 for ASCII art.

> +
> +static void __init sunxi_divs_clk_setup(struct device_node *node,
> +                                       struct divs_data *data)
> +{
> +       struct clk_onecell_data *clk_data;
> +       const char *parent  = node->name;
> +       const char *clk_name;
> +       struct clk **clks, *pclk;
> +       struct clk_hw *gate_hw, *rate_hw;
> +       const struct clk_ops *rate_ops;
> +       struct clk_gate *gate = NULL;
> +       struct clk_fixed_factor *fix_factor;
> +       struct clk_divider *divider;
> +       void *reg;
> +       int i = 0;
> +       int flags, clkflags;
> +
> +       /* Set up factor clock that we will be dividing */
> +       pclk = sunxi_factors_clk_setup(node, data->factors);
> +
> +       reg = of_iomap(node, 0);
> +
> +       clk_data = kmalloc(sizeof(struct clk_onecell_data), GFP_KERNEL);
> +       if (!clk_data)
> +               return;
> +
> +       clks = kzalloc(SUNXI_DIVS_MAX_QTY * sizeof(struct clk *), GFP_KERNEL);
> +       if (!clks)
> +               goto free_clkdata;
> +
> +       clk_data->clks = clks;
> +
> +       /* It's not a good idea to have automatic reparenting changing
> +        * our RAM clock! */
> +       clkflags = !strcmp("pll5", parent) ? 0 : CLK_SET_RATE_PARENT;

Just out of curiosity, did you hit this problem in testing?

Acked-by: Mike Turquette <mturquette@linaro.org>

> +
> +       for (i = 0; i < SUNXI_DIVS_MAX_QTY; i++) {
> +               if (of_property_read_string_index(node, "clock-output-names",
> +                                                 i, &clk_name) != 0)
> +                       break;
> +
> +               gate_hw = NULL;
> +               rate_hw = NULL;
> +               rate_ops = NULL;
> +
> +               /* If this leaf clock can be gated, create a gate */
> +               if (data->div[i].gate) {
> +                       gate = kzalloc(sizeof(*gate), GFP_KERNEL);
> +                       if (!gate)
> +                               goto free_clks;
> +
> +                       gate->reg = reg;
> +                       gate->bit_idx = data->div[i].gate;
> +                       gate->lock = &clk_lock;
> +
> +                       gate_hw = &gate->hw;
> +               }
> +
> +               /* Leaves can be fixed or configurable divisors */
> +               if (data->div[i].fixed) {
> +                       fix_factor = kzalloc(sizeof(*fix_factor), GFP_KERNEL);
> +                       if (!fix_factor)
> +                               goto free_gate;
> +
> +                       fix_factor->mult = 1;
> +                       fix_factor->div = data->div[i].fixed;
> +
> +                       rate_hw = &fix_factor->hw;
> +                       rate_ops = &clk_fixed_factor_ops;
> +               } else {
> +                       divider = kzalloc(sizeof(*divider), GFP_KERNEL);
> +                       if (!divider)
> +                               goto free_gate;
> +
> +                       flags = data->div[i].pow ? CLK_DIVIDER_POWER_OF_TWO : 0;
> +
> +                       divider->reg = reg;
> +                       divider->shift = data->div[i].shift;
> +                       divider->width = SUNXI_DIVISOR_WIDTH;
> +                       divider->flags = flags;
> +                       divider->lock = &clk_lock;
> +                       divider->table = data->div[i].table;
> +
> +                       rate_hw = &divider->hw;
> +                       rate_ops = &clk_divider_ops;
> +               }
> +
> +               /* Wrap the (potential) gate and the divisor on a composite
> +                * clock to unify them */
> +               clks[i] = clk_register_composite(NULL, clk_name, &parent, 1,
> +                                                NULL, NULL,
> +                                                rate_hw, rate_ops,
> +                                                gate_hw, &clk_gate_ops,
> +                                                clkflags);
> +
> +               WARN_ON(IS_ERR(clk_data->clks[i]));
> +               clk_register_clkdev(clks[i], clk_name, NULL);
> +       }
> +
> +       /* The last clock available on the getter is the parent */
> +       clks[i++] = pclk;
> +
> +       /* Adjust to the real max */
> +       clk_data->clk_num = i;
> +
> +       of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
> +
> +       return;
> +
> +free_gate:
> +       kfree(gate);
> +free_clks:
> +       kfree(clks);
> +free_clkdata:
> +       kfree(clk_data);
> +}
> +
> +
> +
>  /* Matches for factors clocks */
>  static const struct of_device_id clk_factors_match[] __initconst = {
>         {.compatible = "allwinner,sun4i-pll1-clk", .data = &sun4i_pll1_data,},
> @@ -637,6 +857,13 @@ static const struct of_device_id clk_div_match[] __initconst = {
>         {}
>  };
>  
> +/* Matches for divided outputs */
> +static const struct of_device_id clk_divs_match[] __initconst = {
> +       {.compatible = "allwinner,sun4i-pll5-clk", .data = &pll5_divs_data,},
> +       {.compatible = "allwinner,sun4i-pll6-clk", .data = &pll6_divs_data,},
> +       {}
> +};
> +
>  /* Matches for mux clocks */
>  static const struct of_device_id clk_mux_match[] __initconst = {
>         {.compatible = "allwinner,sun4i-cpu-clk", .data = &sun4i_cpu_mux_data,},
> @@ -714,6 +941,9 @@ static void __init sunxi_init_clocks(struct device_node *np)
>         /* Register divider clocks */
>         of_sunxi_table_clock_setup(clk_div_match, sunxi_divider_clk_setup);
>  
> +       /* Register divided output clocks */
> +       of_sunxi_table_clock_setup(clk_divs_match, sunxi_divs_clk_setup);
> +
>         /* Register mux clocks */
>         of_sunxi_table_clock_setup(clk_mux_match, sunxi_mux_clk_setup);
>  
> -- 
> 1.8.5.1
>
Emilio López - Dec. 21, 2013, 2:26 a.m.
El 19/12/13 01:59, Mike Turquette escribió:
> Quoting Emilio López (2013-12-17 16:44:57)
>> +
>> +       /* It's not a good idea to have automatic reparenting changing
>> +        * our RAM clock! */
>> +       clkflags = !strcmp("pll5", parent) ? 0 : CLK_SET_RATE_PARENT;
>
> Just out of curiosity, did you hit this problem in testing?

Yes, I believe it was the case that, with automatic reparenting 
implemented, reconfiguring the mmc or similar clock ended up choosing 
pll5_other as ideal parent, and was trying to tune its frequency.

> Acked-by: Mike Turquette <mturquette@linaro.org>

Thanks!

Emilio

Patch

diff --git a/Documentation/devicetree/bindings/clock/sunxi.txt b/Documentation/devicetree/bindings/clock/sunxi.txt
index b8c6cc4..80b2a39 100644
--- a/Documentation/devicetree/bindings/clock/sunxi.txt
+++ b/Documentation/devicetree/bindings/clock/sunxi.txt
@@ -9,6 +9,8 @@  Required properties:
 	"allwinner,sun4i-osc-clk" - for a gatable oscillator
 	"allwinner,sun4i-pll1-clk" - for the main PLL clock and PLL4
 	"allwinner,sun6i-a31-pll1-clk" - for the main PLL clock on A31
+	"allwinner,sun4i-pll5-clk" - for the PLL5 clock
+	"allwinner,sun4i-pll6-clk" - for the PLL6 clock
 	"allwinner,sun4i-cpu-clk" - for the CPU multiplexer clock
 	"allwinner,sun4i-axi-clk" - for the AXI clock
 	"allwinner,sun4i-axi-gates-clk" - for the AXI gates
diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c
index 401169b..84e2186 100644
--- a/drivers/clk/sunxi/clk-sunxi.c
+++ b/drivers/clk/sunxi/clk-sunxi.c
@@ -209,6 +209,40 @@  static void sun6i_a31_get_pll1_factors(u32 *freq, u32 parent_rate,
 }
 
 /**
+ * sun4i_get_pll5_factors() - calculates n, k factors for PLL5
+ * PLL5 rate is calculated as follows
+ * rate = parent_rate * n * (k + 1)
+ * parent_rate is always 24Mhz
+ */
+
+static void sun4i_get_pll5_factors(u32 *freq, u32 parent_rate,
+				   u8 *n, u8 *k, u8 *m, u8 *p)
+{
+	u8 div;
+
+	/* Normalize value to a parent_rate multiple (24M) */
+	div = *freq / parent_rate;
+	*freq = parent_rate * div;
+
+	/* we were called to round the frequency, we can now return */
+	if (n == NULL)
+		return;
+
+	if (div < 31)
+		*k = 0;
+	else if (div / 2 < 31)
+		*k = 1;
+	else if (div / 3 < 31)
+		*k = 2;
+	else
+		*k = 3;
+
+	*n = DIV_ROUND_UP(div, (*k+1));
+}
+
+
+
+/**
  * sun4i_get_apb1_factors() - calculates m, p factors for APB1
  * APB1 rate is calculated as follows
  * rate = (parent_rate >> p) / (m + 1);
@@ -284,6 +318,13 @@  static struct clk_factors_config sun6i_a31_pll1_config = {
 	.mwidth = 2,
 };
 
+static struct clk_factors_config sun4i_pll5_config = {
+	.nshift = 8,
+	.nwidth = 5,
+	.kshift = 4,
+	.kwidth = 2,
+};
+
 static struct clk_factors_config sun4i_apb1_config = {
 	.mshift = 0,
 	.mwidth = 5,
@@ -303,6 +344,12 @@  static const struct factors_data sun6i_a31_pll1_data __initconst = {
 	.getter = sun6i_a31_get_pll1_factors,
 };
 
+static const struct factors_data sun4i_pll5_data __initconst = {
+	.enable = 31,
+	.table = &sun4i_pll5_config,
+	.getter = sun4i_get_pll5_factors,
+};
+
 static const struct factors_data sun4i_apb1_data __initconst = {
 	.table = &sun4i_apb1_config,
 	.getter = sun4i_get_apb1_factors,
@@ -620,6 +667,179 @@  static void __init sunxi_gates_clk_setup(struct device_node *node,
 	of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
 }
 
+
+
+/**
+ * sunxi_divs_clk_setup() helper data
+ */
+
+#define SUNXI_DIVS_MAX_QTY	2
+#define SUNXI_DIVISOR_WIDTH	2
+
+struct divs_data {
+	const struct factors_data *factors; /* data for the factor clock */
+	struct {
+		u8 fixed; /* is it a fixed divisor? if not... */
+		struct clk_div_table *table; /* is it a table based divisor? */
+		u8 shift; /* otherwise it's a normal divisor with this shift */
+		u8 pow;   /* is it power-of-two based? */
+		u8 gate;  /* is it independently gateable? */
+	} div[SUNXI_DIVS_MAX_QTY];
+};
+
+static struct clk_div_table pll6_sata_tbl[] = {
+	{ .val = 0, .div = 6, },
+	{ .val = 1, .div = 12, },
+	{ .val = 2, .div = 18, },
+	{ .val = 3, .div = 24, },
+	{ } /* sentinel */
+};
+
+static const struct divs_data pll5_divs_data __initconst = {
+	.factors = &sun4i_pll5_data,
+	.div = {
+		{ .shift = 0, .pow = 0, }, /* M, DDR */
+		{ .shift = 16, .pow = 1, }, /* P, other */
+	}
+};
+
+static const struct divs_data pll6_divs_data __initconst = {
+	.factors = &sun4i_pll5_data,
+	.div = {
+		{ .shift = 0, .table = pll6_sata_tbl, .gate = 14 }, /* M, SATA */
+		{ .fixed = 2 }, /* P, other */
+	}
+};
+
+/**
+ * sunxi_divs_clk_setup() - Setup function for leaf divisors on clocks
+ *
+ * These clocks look something like this
+ *            ________________________
+ *           |         ___divisor 1---|----> to consumer
+ * parent >--|  pll___/___divisor 2---|----> to consumer
+ *           |        \_______________|____> to consumer
+ *           |________________________|
+ */
+
+static void __init sunxi_divs_clk_setup(struct device_node *node,
+					struct divs_data *data)
+{
+	struct clk_onecell_data *clk_data;
+	const char *parent  = node->name;
+	const char *clk_name;
+	struct clk **clks, *pclk;
+	struct clk_hw *gate_hw, *rate_hw;
+	const struct clk_ops *rate_ops;
+	struct clk_gate *gate = NULL;
+	struct clk_fixed_factor *fix_factor;
+	struct clk_divider *divider;
+	void *reg;
+	int i = 0;
+	int flags, clkflags;
+
+	/* Set up factor clock that we will be dividing */
+	pclk = sunxi_factors_clk_setup(node, data->factors);
+
+	reg = of_iomap(node, 0);
+
+	clk_data = kmalloc(sizeof(struct clk_onecell_data), GFP_KERNEL);
+	if (!clk_data)
+		return;
+
+	clks = kzalloc(SUNXI_DIVS_MAX_QTY * sizeof(struct clk *), GFP_KERNEL);
+	if (!clks)
+		goto free_clkdata;
+
+	clk_data->clks = clks;
+
+	/* It's not a good idea to have automatic reparenting changing
+	 * our RAM clock! */
+	clkflags = !strcmp("pll5", parent) ? 0 : CLK_SET_RATE_PARENT;
+
+	for (i = 0; i < SUNXI_DIVS_MAX_QTY; i++) {
+		if (of_property_read_string_index(node, "clock-output-names",
+						  i, &clk_name) != 0)
+			break;
+
+		gate_hw = NULL;
+		rate_hw = NULL;
+		rate_ops = NULL;
+
+		/* If this leaf clock can be gated, create a gate */
+		if (data->div[i].gate) {
+			gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+			if (!gate)
+				goto free_clks;
+
+			gate->reg = reg;
+			gate->bit_idx = data->div[i].gate;
+			gate->lock = &clk_lock;
+
+			gate_hw = &gate->hw;
+		}
+
+		/* Leaves can be fixed or configurable divisors */
+		if (data->div[i].fixed) {
+			fix_factor = kzalloc(sizeof(*fix_factor), GFP_KERNEL);
+			if (!fix_factor)
+				goto free_gate;
+
+			fix_factor->mult = 1;
+			fix_factor->div = data->div[i].fixed;
+
+			rate_hw = &fix_factor->hw;
+			rate_ops = &clk_fixed_factor_ops;
+		} else {
+			divider = kzalloc(sizeof(*divider), GFP_KERNEL);
+			if (!divider)
+				goto free_gate;
+
+			flags = data->div[i].pow ? CLK_DIVIDER_POWER_OF_TWO : 0;
+
+			divider->reg = reg;
+			divider->shift = data->div[i].shift;
+			divider->width = SUNXI_DIVISOR_WIDTH;
+			divider->flags = flags;
+			divider->lock = &clk_lock;
+			divider->table = data->div[i].table;
+
+			rate_hw = &divider->hw;
+			rate_ops = &clk_divider_ops;
+		}
+
+		/* Wrap the (potential) gate and the divisor on a composite
+		 * clock to unify them */
+		clks[i] = clk_register_composite(NULL, clk_name, &parent, 1,
+						 NULL, NULL,
+						 rate_hw, rate_ops,
+						 gate_hw, &clk_gate_ops,
+						 clkflags);
+
+		WARN_ON(IS_ERR(clk_data->clks[i]));
+		clk_register_clkdev(clks[i], clk_name, NULL);
+	}
+
+	/* The last clock available on the getter is the parent */
+	clks[i++] = pclk;
+
+	/* Adjust to the real max */
+	clk_data->clk_num = i;
+
+	of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
+
+	return;
+
+free_gate:
+	kfree(gate);
+free_clks:
+	kfree(clks);
+free_clkdata:
+	kfree(clk_data);
+}
+
+
+
 /* Matches for factors clocks */
 static const struct of_device_id clk_factors_match[] __initconst = {
 	{.compatible = "allwinner,sun4i-pll1-clk", .data = &sun4i_pll1_data,},
@@ -637,6 +857,13 @@  static const struct of_device_id clk_div_match[] __initconst = {
 	{}
 };
 
+/* Matches for divided outputs */
+static const struct of_device_id clk_divs_match[] __initconst = {
+	{.compatible = "allwinner,sun4i-pll5-clk", .data = &pll5_divs_data,},
+	{.compatible = "allwinner,sun4i-pll6-clk", .data = &pll6_divs_data,},
+	{}
+};
+
 /* Matches for mux clocks */
 static const struct of_device_id clk_mux_match[] __initconst = {
 	{.compatible = "allwinner,sun4i-cpu-clk", .data = &sun4i_cpu_mux_data,},
@@ -714,6 +941,9 @@  static void __init sunxi_init_clocks(struct device_node *np)
 	/* Register divider clocks */
 	of_sunxi_table_clock_setup(clk_div_match, sunxi_divider_clk_setup);
 
+	/* Register divided output clocks */
+	of_sunxi_table_clock_setup(clk_divs_match, sunxi_divs_clk_setup);
+
 	/* Register mux clocks */
 	of_sunxi_table_clock_setup(clk_mux_match, sunxi_mux_clk_setup);