clk: st: Support for PLLs inside ClockGenA(s)
authorGabriel FERNANDEZ <gabriel.fernandez@st.com>
Thu, 27 Feb 2014 15:24:15 +0000 (16:24 +0100)
committerMike Turquette <mturquette@linaro.org>
Tue, 25 Mar 2014 22:58:56 +0000 (15:58 -0700)
The patch supports the c65/c32 type PLLs used by ClockGenA(s)

PLL clock : It includes support for all c65/c32 type PLLs
inside ClockGenA(s) : implemented as Fixed Parent / Fixed Rate clock,
with clock rate calculated reading H/w settings done at BOOT.

c65 PLLs have 2 outputs : HS and LS
c32 PLLs have 1-4 outputs : ODFx

Signed-off-by: Pankaj Dev <pankaj.dev@st.com>
Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
drivers/clk/st/Makefile
drivers/clk/st/clkgen-pll.c [new file with mode: 0644]
drivers/clk/st/clkgen.h [new file with mode: 0644]

index e42b370edef9fd49572ce9701544eaad04c03a39..b7b10f93dbe96663be7f2d897f84d6ab832a28f7 100644 (file)
@@ -1 +1 @@
-obj-y += clkgen-mux.o
+obj-y += clkgen-mux.o clkgen-pll.o
diff --git a/drivers/clk/st/clkgen-pll.c b/drivers/clk/st/clkgen-pll.c
new file mode 100644 (file)
index 0000000..c6b38b0
--- /dev/null
@@ -0,0 +1,559 @@
+/*
+ * Copyright (C) 2014 STMicroelectronics (R&D) Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+/*
+ * Authors:
+ * Stephen Gallimore <stephen.gallimore@st.com>,
+ * Pankaj Dev <pankaj.dev@st.com>.
+ */
+
+#include <linux/slab.h>
+#include <linux/of_address.h>
+#include <linux/clk-provider.h>
+
+#include "clkgen.h"
+
+static DEFINE_SPINLOCK(clkgena_c32_odf_lock);
+
+/*
+ * Common PLL configuration register bits for PLL800 and PLL1600 C65
+ */
+#define C65_MDIV_PLL800_MASK   (0xff)
+#define C65_MDIV_PLL1600_MASK  (0x7)
+#define C65_NDIV_MASK          (0xff)
+#define C65_PDIV_MASK          (0x7)
+
+/*
+ * PLL configuration register bits for PLL3200 C32
+ */
+#define C32_NDIV_MASK (0xff)
+#define C32_IDF_MASK (0x7)
+#define C32_ODF_MASK (0x3f)
+#define C32_LDF_MASK (0x7f)
+
+#define C32_MAX_ODFS (4)
+
+struct clkgen_pll_data {
+       struct clkgen_field pdn_status;
+       struct clkgen_field locked_status;
+       struct clkgen_field mdiv;
+       struct clkgen_field ndiv;
+       struct clkgen_field pdiv;
+       struct clkgen_field idf;
+       struct clkgen_field ldf;
+       unsigned int num_odfs;
+       struct clkgen_field odf[C32_MAX_ODFS];
+       struct clkgen_field odf_gate[C32_MAX_ODFS];
+       const struct clk_ops *ops;
+};
+
+static const struct clk_ops st_pll1600c65_ops;
+static const struct clk_ops st_pll800c65_ops;
+static const struct clk_ops stm_pll3200c32_ops;
+static const struct clk_ops st_pll1200c32_ops;
+
+static struct clkgen_pll_data st_pll1600c65_ax = {
+       .pdn_status     = CLKGEN_FIELD(0x0, 0x1,                        19),
+       .locked_status  = CLKGEN_FIELD(0x0, 0x1,                        31),
+       .mdiv           = CLKGEN_FIELD(0x0, C65_MDIV_PLL1600_MASK,      0),
+       .ndiv           = CLKGEN_FIELD(0x0, C65_NDIV_MASK,              8),
+       .ops            = &st_pll1600c65_ops
+};
+
+static struct clkgen_pll_data st_pll800c65_ax = {
+       .pdn_status     = CLKGEN_FIELD(0x0,     0x1,                    19),
+       .locked_status  = CLKGEN_FIELD(0x0,     0x1,                    31),
+       .mdiv           = CLKGEN_FIELD(0x0,     C65_MDIV_PLL800_MASK,   0),
+       .ndiv           = CLKGEN_FIELD(0x0,     C65_NDIV_MASK,          8),
+       .pdiv           = CLKGEN_FIELD(0x0,     C65_PDIV_MASK,          16),
+       .ops            = &st_pll800c65_ops
+};
+
+static struct clkgen_pll_data st_pll3200c32_a1x_0 = {
+       .pdn_status     = CLKGEN_FIELD(0x0,     0x1,                    31),
+       .locked_status  = CLKGEN_FIELD(0x4,     0x1,                    31),
+       .ndiv           = CLKGEN_FIELD(0x0,     C32_NDIV_MASK,          0x0),
+       .idf            = CLKGEN_FIELD(0x4,     C32_IDF_MASK,           0x0),
+       .num_odfs = 4,
+       .odf =  {       CLKGEN_FIELD(0x54,      C32_ODF_MASK,           4),
+                       CLKGEN_FIELD(0x54,      C32_ODF_MASK,           10),
+                       CLKGEN_FIELD(0x54,      C32_ODF_MASK,           16),
+                       CLKGEN_FIELD(0x54,      C32_ODF_MASK,           22) },
+       .odf_gate = {   CLKGEN_FIELD(0x54,      0x1,                    0),
+                       CLKGEN_FIELD(0x54,      0x1,                    1),
+                       CLKGEN_FIELD(0x54,      0x1,                    2),
+                       CLKGEN_FIELD(0x54,      0x1,                    3) },
+       .ops            = &stm_pll3200c32_ops,
+};
+
+static struct clkgen_pll_data st_pll3200c32_a1x_1 = {
+       .pdn_status     = CLKGEN_FIELD(0xC,     0x1,                    31),
+       .locked_status  = CLKGEN_FIELD(0x10,    0x1,                    31),
+       .ndiv           = CLKGEN_FIELD(0xC,     C32_NDIV_MASK,          0x0),
+       .idf            = CLKGEN_FIELD(0x10,    C32_IDF_MASK,           0x0),
+       .num_odfs = 4,
+       .odf = {        CLKGEN_FIELD(0x58,      C32_ODF_MASK,           4),
+                       CLKGEN_FIELD(0x58,      C32_ODF_MASK,           10),
+                       CLKGEN_FIELD(0x58,      C32_ODF_MASK,           16),
+                       CLKGEN_FIELD(0x58,      C32_ODF_MASK,           22) },
+       .odf_gate = {   CLKGEN_FIELD(0x58,      0x1,                    0),
+                       CLKGEN_FIELD(0x58,      0x1,                    1),
+                       CLKGEN_FIELD(0x58,      0x1,                    2),
+                       CLKGEN_FIELD(0x58,      0x1,                    3) },
+       .ops            = &stm_pll3200c32_ops,
+};
+
+/**
+ * DOC: Clock Generated by PLL, rate set and enabled by bootloader
+ *
+ * Traits of this clock:
+ * prepare - clk_(un)prepare only ensures parent is (un)prepared
+ * enable - clk_enable/disable only ensures parent is enabled
+ * rate - rate is fixed. No clk_set_rate support
+ * parent - fixed parent.  No clk_set_parent support
+ */
+
+/**
+ * PLL clock that is integrated in the ClockGenA instances on the STiH415
+ * and STiH416.
+ *
+ * @hw: handle between common and hardware-specific interfaces.
+ * @type: PLL instance type.
+ * @regs_base: base of the PLL configuration register(s).
+ *
+ */
+struct clkgen_pll {
+       struct clk_hw           hw;
+       struct clkgen_pll_data  *data;
+       void __iomem            *regs_base;
+};
+
+#define to_clkgen_pll(_hw) container_of(_hw, struct clkgen_pll, hw)
+
+static int clkgen_pll_is_locked(struct clk_hw *hw)
+{
+       struct clkgen_pll *pll = to_clkgen_pll(hw);
+       u32 locked = CLKGEN_READ(pll, locked_status);
+
+       return !!locked;
+}
+
+static int clkgen_pll_is_enabled(struct clk_hw *hw)
+{
+       struct clkgen_pll *pll = to_clkgen_pll(hw);
+       u32 poweroff = CLKGEN_READ(pll, pdn_status);
+       return !poweroff;
+}
+
+unsigned long recalc_stm_pll800c65(struct clk_hw *hw,
+               unsigned long parent_rate)
+{
+       struct clkgen_pll *pll = to_clkgen_pll(hw);
+       unsigned long mdiv, ndiv, pdiv;
+       unsigned long rate;
+       uint64_t res;
+
+       if (!clkgen_pll_is_enabled(hw) || !clkgen_pll_is_locked(hw))
+               return 0;
+
+       pdiv = CLKGEN_READ(pll, pdiv);
+       mdiv = CLKGEN_READ(pll, mdiv);
+       ndiv = CLKGEN_READ(pll, ndiv);
+
+       if (!mdiv)
+               mdiv++; /* mdiv=0 or 1 => MDIV=1 */
+
+       res = (uint64_t)2 * (uint64_t)parent_rate * (uint64_t)ndiv;
+       rate = (unsigned long)div64_u64(res, mdiv * (1 << pdiv));
+
+       pr_debug("%s:%s rate %lu\n", __clk_get_name(hw->clk), __func__, rate);
+
+       return rate;
+
+}
+
+unsigned long recalc_stm_pll1600c65(struct clk_hw *hw,
+               unsigned long parent_rate)
+{
+       struct clkgen_pll *pll = to_clkgen_pll(hw);
+       unsigned long mdiv, ndiv;
+       unsigned long rate;
+
+       if (!clkgen_pll_is_enabled(hw) || !clkgen_pll_is_locked(hw))
+               return 0;
+
+       mdiv = CLKGEN_READ(pll, mdiv);
+       ndiv = CLKGEN_READ(pll, ndiv);
+
+       if (!mdiv)
+               mdiv = 1;
+
+       /* Note: input is divided by 1000 to avoid overflow */
+       rate = ((2 * (parent_rate / 1000) * ndiv) / mdiv) * 1000;
+
+       pr_debug("%s:%s rate %lu\n", __clk_get_name(hw->clk), __func__, rate);
+
+       return rate;
+}
+
+unsigned long recalc_stm_pll3200c32(struct clk_hw *hw,
+               unsigned long parent_rate)
+{
+       struct clkgen_pll *pll = to_clkgen_pll(hw);
+       unsigned long ndiv, idf;
+       unsigned long rate = 0;
+
+       if (!clkgen_pll_is_enabled(hw) || !clkgen_pll_is_locked(hw))
+               return 0;
+
+       ndiv = CLKGEN_READ(pll, ndiv);
+       idf = CLKGEN_READ(pll, idf);
+
+       if (idf)
+               /* Note: input is divided to avoid overflow */
+               rate = ((2 * (parent_rate/1000) * ndiv) / idf) * 1000;
+
+       pr_debug("%s:%s rate %lu\n", __clk_get_name(hw->clk), __func__, rate);
+
+       return rate;
+}
+
+unsigned long recalc_stm_pll1200c32(struct clk_hw *hw,
+               unsigned long parent_rate)
+{
+       struct clkgen_pll *pll = to_clkgen_pll(hw);
+       unsigned long odf, ldf, idf;
+       unsigned long rate;
+
+       if (!clkgen_pll_is_enabled(hw) || !clkgen_pll_is_locked(hw))
+               return 0;
+
+       odf = CLKGEN_READ(pll, odf[0]);
+       ldf = CLKGEN_READ(pll, ldf);
+       idf = CLKGEN_READ(pll, idf);
+
+       if (!idf) /* idf==0 means 1 */
+               idf = 1;
+       if (!odf) /* odf==0 means 1 */
+               odf = 1;
+
+       /* Note: input is divided by 1000 to avoid overflow */
+       rate = (((parent_rate / 1000) * ldf) / (odf * idf)) * 1000;
+
+       pr_debug("%s:%s rate %lu\n", __clk_get_name(hw->clk), __func__, rate);
+
+       return rate;
+}
+
+static const struct clk_ops st_pll1600c65_ops = {
+       .is_enabled     = clkgen_pll_is_enabled,
+       .recalc_rate    = recalc_stm_pll1600c65,
+};
+
+static const struct clk_ops st_pll800c65_ops = {
+       .is_enabled     = clkgen_pll_is_enabled,
+       .recalc_rate    = recalc_stm_pll800c65,
+};
+
+static const struct clk_ops stm_pll3200c32_ops = {
+       .is_enabled     = clkgen_pll_is_enabled,
+       .recalc_rate    = recalc_stm_pll3200c32,
+};
+
+static const struct clk_ops st_pll1200c32_ops = {
+       .is_enabled     = clkgen_pll_is_enabled,
+       .recalc_rate    = recalc_stm_pll1200c32,
+};
+
+static struct clk * __init clkgen_pll_register(const char *parent_name,
+                               struct clkgen_pll_data  *pll_data,
+                               void __iomem *reg,
+                               const char *clk_name)
+{
+       struct clkgen_pll *pll;
+       struct clk *clk;
+       struct clk_init_data init;
+
+       pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+       if (!pll)
+               return ERR_PTR(-ENOMEM);
+
+       init.name = clk_name;
+       init.ops = pll_data->ops;
+
+       init.flags = CLK_IS_BASIC;
+       init.parent_names = &parent_name;
+       init.num_parents  = 1;
+
+       pll->data = pll_data;
+       pll->regs_base = reg;
+       pll->hw.init = &init;
+
+       clk = clk_register(NULL, &pll->hw);
+       if (IS_ERR(clk)) {
+               kfree(pll);
+               return clk;
+       }
+
+       pr_debug("%s: parent %s rate %lu\n",
+                       __clk_get_name(clk),
+                       __clk_get_name(clk_get_parent(clk)),
+                       clk_get_rate(clk));
+
+       return clk;
+}
+
+static struct clk * __init clkgen_c65_lsdiv_register(const char *parent_name,
+                                                    const char *clk_name)
+{
+       struct clk *clk;
+
+       clk = clk_register_fixed_factor(NULL, clk_name, parent_name, 0, 1, 2);
+       if (IS_ERR(clk))
+               return clk;
+
+       pr_debug("%s: parent %s rate %lu\n",
+                       __clk_get_name(clk),
+                       __clk_get_name(clk_get_parent(clk)),
+                       clk_get_rate(clk));
+       return clk;
+}
+
+static void __iomem * __init clkgen_get_register_base(
+                               struct device_node *np)
+{
+       struct device_node *pnode;
+       void __iomem *reg = NULL;
+
+       pnode = of_get_parent(np);
+       if (!pnode)
+               return NULL;
+
+       reg = of_iomap(pnode, 0);
+
+       of_node_put(pnode);
+       return reg;
+}
+
+#define CLKGENAx_PLL0_OFFSET 0x0
+#define CLKGENAx_PLL1_OFFSET 0x4
+
+static void __init clkgena_c65_pll_setup(struct device_node *np)
+{
+       const int num_pll_outputs = 3;
+       struct clk_onecell_data *clk_data;
+       const char *parent_name;
+       void __iomem *reg;
+       const char *clk_name;
+
+       parent_name = of_clk_get_parent_name(np, 0);
+       if (!parent_name)
+               return;
+
+       reg = clkgen_get_register_base(np);
+       if (!reg)
+               return;
+
+       clk_data = kzalloc(sizeof(*clk_data), GFP_KERNEL);
+       if (!clk_data)
+               return;
+
+       clk_data->clk_num = num_pll_outputs;
+       clk_data->clks = kzalloc(clk_data->clk_num * sizeof(struct clk *),
+                                GFP_KERNEL);
+
+       if (!clk_data->clks)
+               goto err;
+
+       if (of_property_read_string_index(np, "clock-output-names",
+                                         0, &clk_name))
+               goto err;
+
+       /*
+        * PLL0 HS (high speed) output
+        */
+       clk_data->clks[0] = clkgen_pll_register(parent_name,
+                                               &st_pll1600c65_ax,
+                                               reg + CLKGENAx_PLL0_OFFSET,
+                                               clk_name);
+
+       if (IS_ERR(clk_data->clks[0]))
+               goto err;
+
+       if (of_property_read_string_index(np, "clock-output-names",
+                                         1, &clk_name))
+               goto err;
+
+       /*
+        * PLL0 LS (low speed) output, which is a fixed divide by 2 of the
+        * high speed output.
+        */
+       clk_data->clks[1] = clkgen_c65_lsdiv_register(__clk_get_name
+                                                     (clk_data->clks[0]),
+                                                     clk_name);
+
+       if (IS_ERR(clk_data->clks[1]))
+               goto err;
+
+       if (of_property_read_string_index(np, "clock-output-names",
+                                         2, &clk_name))
+               goto err;
+
+       /*
+        * PLL1 output
+        */
+       clk_data->clks[2] = clkgen_pll_register(parent_name,
+                                               &st_pll800c65_ax,
+                                               reg + CLKGENAx_PLL1_OFFSET,
+                                               clk_name);
+
+       if (IS_ERR(clk_data->clks[2]))
+               goto err;
+
+       of_clk_add_provider(np, of_clk_src_onecell_get, clk_data);
+       return;
+
+err:
+       kfree(clk_data->clks);
+       kfree(clk_data);
+}
+CLK_OF_DECLARE(clkgena_c65_plls,
+              "st,clkgena-plls-c65", clkgena_c65_pll_setup);
+
+static struct clk * __init clkgen_odf_register(const char *parent_name,
+                                              void * __iomem reg,
+                                              struct clkgen_pll_data *pll_data,
+                                              int odf,
+                                              spinlock_t *odf_lock,
+                                              const char *odf_name)
+{
+       struct clk *clk;
+       unsigned long flags;
+       struct clk_gate *gate;
+       struct clk_divider *div;
+
+       flags = CLK_GET_RATE_NOCACHE | CLK_SET_RATE_GATE;
+
+       gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+       if (!gate)
+               return ERR_PTR(-ENOMEM);
+
+       gate->flags = CLK_GATE_SET_TO_DISABLE;
+       gate->reg = reg + pll_data->odf_gate[odf].offset;
+       gate->bit_idx = pll_data->odf_gate[odf].shift;
+       gate->lock = odf_lock;
+
+       div = kzalloc(sizeof(*div), GFP_KERNEL);
+       if (!div)
+               return ERR_PTR(-ENOMEM);
+
+       div->flags = CLK_DIVIDER_ONE_BASED | CLK_DIVIDER_ALLOW_ZERO;
+       div->reg = reg + pll_data->odf[odf].offset;
+       div->shift = pll_data->odf[odf].shift;
+       div->width = fls(pll_data->odf[odf].mask);
+       div->lock = odf_lock;
+
+       clk = clk_register_composite(NULL, odf_name, &parent_name, 1,
+                                    NULL, NULL,
+                                    &div->hw, &clk_divider_ops,
+                                    &gate->hw, &clk_gate_ops,
+                                    flags);
+       if (IS_ERR(clk))
+               return clk;
+
+       pr_debug("%s: parent %s rate %lu\n",
+                       __clk_get_name(clk),
+                       __clk_get_name(clk_get_parent(clk)),
+                       clk_get_rate(clk));
+       return clk;
+}
+
+static struct of_device_id c32_pll_of_match[] = {
+       {
+               .compatible = "st,plls-c32-a1x-0",
+               .data = &st_pll3200c32_a1x_0,
+       },
+       {
+               .compatible = "st,plls-c32-a1x-1",
+               .data = &st_pll3200c32_a1x_1,
+       },
+       {}
+};
+
+static void __init clkgen_c32_pll_setup(struct device_node *np)
+{
+       const struct of_device_id *match;
+       struct clk *clk;
+       const char *parent_name, *pll_name;
+       void __iomem *pll_base;
+       int num_odfs, odf;
+       struct clk_onecell_data *clk_data;
+       struct clkgen_pll_data  *data;
+
+       match = of_match_node(c32_pll_of_match, np);
+       if (!match) {
+               pr_err("%s: No matching data\n", __func__);
+               return;
+       }
+
+       data = (struct clkgen_pll_data *) match->data;
+
+       parent_name = of_clk_get_parent_name(np, 0);
+       if (!parent_name)
+               return;
+
+       pll_base = clkgen_get_register_base(np);
+       if (!pll_base)
+               return;
+
+       clk = clkgen_pll_register(parent_name, data, pll_base, np->name);
+       if (IS_ERR(clk))
+               return;
+
+       pll_name = __clk_get_name(clk);
+
+       num_odfs = data->num_odfs;
+
+       clk_data = kzalloc(sizeof(*clk_data), GFP_KERNEL);
+       if (!clk_data)
+               return;
+
+       clk_data->clk_num = num_odfs;
+       clk_data->clks = kzalloc(clk_data->clk_num * sizeof(struct clk *),
+                                GFP_KERNEL);
+
+       if (!clk_data->clks)
+               goto err;
+
+       for (odf = 0; odf < num_odfs; odf++) {
+               struct clk *clk;
+               const char *clk_name;
+
+               if (of_property_read_string_index(np, "clock-output-names",
+                                                 odf, &clk_name))
+                       return;
+
+               clk = clkgen_odf_register(pll_name, pll_base, data,
+                               odf, &clkgena_c32_odf_lock, clk_name);
+               if (IS_ERR(clk))
+                       goto err;
+
+               clk_data->clks[odf] = clk;
+       }
+
+       of_clk_add_provider(np, of_clk_src_onecell_get, clk_data);
+       return;
+
+err:
+       kfree(pll_name);
+       kfree(clk_data->clks);
+       kfree(clk_data);
+}
+CLK_OF_DECLARE(clkgen_c32_pll, "st,clkgen-plls-c32", clkgen_c32_pll_setup);
diff --git a/drivers/clk/st/clkgen.h b/drivers/clk/st/clkgen.h
new file mode 100644 (file)
index 0000000..35c8632
--- /dev/null
@@ -0,0 +1,48 @@
+/************************************************************************
+File  : Clock H/w specific Information
+
+Author: Pankaj Dev <pankaj.dev@st.com>
+
+Copyright (C) 2014 STMicroelectronics
+************************************************************************/
+
+#ifndef __CLKGEN_INFO_H
+#define __CLKGEN_INFO_H
+
+struct clkgen_field {
+       unsigned int offset;
+       unsigned int mask;
+       unsigned int shift;
+};
+
+static inline unsigned long clkgen_read(void __iomem   *base,
+                                         struct clkgen_field *field)
+{
+       return (readl(base + field->offset) >> field->shift) & field->mask;
+}
+
+
+static inline void clkgen_write(void __iomem *base, struct clkgen_field *field,
+                                 unsigned long val)
+{
+       writel((readl(base + field->offset) &
+              ~(field->mask << field->shift)) | (val << field->shift),
+              base + field->offset);
+
+       return;
+}
+
+#define CLKGEN_FIELD(_offset, _mask, _shift) {         \
+                               .offset = _offset,      \
+                               .mask   = _mask,        \
+                               .shift  = _shift,       \
+                               }
+
+#define CLKGEN_READ(pll, field) clkgen_read(pll->regs_base, \
+               &pll->data->field)
+
+#define CLKGEN_WRITE(pll, field, val) clkgen_write(pll->regs_base, \
+               &pll->data->field, val)
+
+#endif /*__CLKGEN_INFO_H*/
+