--- /dev/null
+/*
+ * OMAP APLL clock support
+ *
+ * Copyright (C) 2013 Texas Instruments, Inc.
+ *
+ * J Keerthy <j-keerthy@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/log2.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/clk/ti.h>
+#include <linux/delay.h>
+
+#define APLL_FORCE_LOCK 0x1
+#define APLL_AUTO_IDLE 0x2
+#define MAX_APLL_WAIT_TRIES 1000000
+
+#undef pr_fmt
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+static int dra7_apll_enable(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ int r = 0, i = 0;
+ struct dpll_data *ad;
+ const char *clk_name;
+ u8 state = 1;
+ u32 v;
+
+ ad = clk->dpll_data;
+ if (!ad)
+ return -EINVAL;
+
+ clk_name = __clk_get_name(clk->hw.clk);
+
+ state <<= __ffs(ad->idlest_mask);
+
+ /* Check is already locked */
+ v = ti_clk_ll_ops->clk_readl(ad->idlest_reg);
+
+ if ((v & ad->idlest_mask) == state)
+ return r;
+
+ v = ti_clk_ll_ops->clk_readl(ad->control_reg);
+ v &= ~ad->enable_mask;
+ v |= APLL_FORCE_LOCK << __ffs(ad->enable_mask);
+ ti_clk_ll_ops->clk_writel(v, ad->control_reg);
+
+ state <<= __ffs(ad->idlest_mask);
+
+ while (1) {
+ v = ti_clk_ll_ops->clk_readl(ad->idlest_reg);
+ if ((v & ad->idlest_mask) == state)
+ break;
+ if (i > MAX_APLL_WAIT_TRIES)
+ break;
+ i++;
+ udelay(1);
+ }
+
+ if (i == MAX_APLL_WAIT_TRIES) {
+ pr_warn("clock: %s failed transition to '%s'\n",
+ clk_name, (state) ? "locked" : "bypassed");
+ r = -EBUSY;
+ } else
+ pr_debug("clock: %s transition to '%s' in %d loops\n",
+ clk_name, (state) ? "locked" : "bypassed", i);
+
+ return r;
+}
+
+static void dra7_apll_disable(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ struct dpll_data *ad;
+ u8 state = 1;
+ u32 v;
+
+ ad = clk->dpll_data;
+
+ state <<= __ffs(ad->idlest_mask);
+
+ v = ti_clk_ll_ops->clk_readl(ad->control_reg);
+ v &= ~ad->enable_mask;
+ v |= APLL_AUTO_IDLE << __ffs(ad->enable_mask);
+ ti_clk_ll_ops->clk_writel(v, ad->control_reg);
+}
+
+static int dra7_apll_is_enabled(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ struct dpll_data *ad;
+ u32 v;
+
+ ad = clk->dpll_data;
+
+ v = ti_clk_ll_ops->clk_readl(ad->control_reg);
+ v &= ad->enable_mask;
+
+ v >>= __ffs(ad->enable_mask);
+
+ return v == APLL_AUTO_IDLE ? 0 : 1;
+}
+
+static u8 dra7_init_apll_parent(struct clk_hw *hw)
+{
+ return 0;
+}
+
+static const struct clk_ops apll_ck_ops = {
+ .enable = &dra7_apll_enable,
+ .disable = &dra7_apll_disable,
+ .is_enabled = &dra7_apll_is_enabled,
+ .get_parent = &dra7_init_apll_parent,
+};
+
+static void __init omap_clk_register_apll(struct clk_hw *hw,
+ struct device_node *node)
+{
+ struct clk_hw_omap *clk_hw = to_clk_hw_omap(hw);
+ struct dpll_data *ad = clk_hw->dpll_data;
+ struct clk *clk;
+
+ ad->clk_ref = of_clk_get(node, 0);
+ ad->clk_bypass = of_clk_get(node, 1);
+
+ if (IS_ERR(ad->clk_ref) || IS_ERR(ad->clk_bypass)) {
+ pr_debug("clk-ref or clk-bypass for %s not ready, retry\n",
+ node->name);
+ if (!ti_clk_retry_init(node, hw, omap_clk_register_apll))
+ return;
+
+ goto cleanup;
+ }
+
+ clk = clk_register(NULL, &clk_hw->hw);
+ if (!IS_ERR(clk)) {
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ kfree(clk_hw->hw.init->parent_names);
+ kfree(clk_hw->hw.init);
+ return;
+ }
+
+cleanup:
+ kfree(clk_hw->dpll_data);
+ kfree(clk_hw->hw.init->parent_names);
+ kfree(clk_hw->hw.init);
+ kfree(clk_hw);
+}
+
+static void __init of_dra7_apll_setup(struct device_node *node)
+{
+ struct dpll_data *ad = NULL;
+ struct clk_hw_omap *clk_hw = NULL;
+ struct clk_init_data *init = NULL;
+ const char **parent_names = NULL;
+ int i;
+
+ ad = kzalloc(sizeof(*ad), GFP_KERNEL);
+ clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL);
+ init = kzalloc(sizeof(*init), GFP_KERNEL);
+ if (!ad || !clk_hw || !init)
+ goto cleanup;
+
+ clk_hw->dpll_data = ad;
+ clk_hw->hw.init = init;
+ clk_hw->flags = MEMMAP_ADDRESSING;
+
+ init->name = node->name;
+ init->ops = &apll_ck_ops;
+
+ init->num_parents = of_clk_get_parent_count(node);
+ if (init->num_parents < 1) {
+ pr_err("dra7 apll %s must have parent(s)\n", node->name);
+ goto cleanup;
+ }
+
+ parent_names = kzalloc(sizeof(char *) * init->num_parents, GFP_KERNEL);
+ if (!parent_names)
+ goto cleanup;
+
+ for (i = 0; i < init->num_parents; i++)
+ parent_names[i] = of_clk_get_parent_name(node, i);
+
+ init->parent_names = parent_names;
+
+ ad->control_reg = ti_clk_get_reg_addr(node, 0);
+ ad->idlest_reg = ti_clk_get_reg_addr(node, 1);
+
+ if (IS_ERR(ad->control_reg) || IS_ERR(ad->idlest_reg))
+ goto cleanup;
+
+ ad->idlest_mask = 0x1;
+ ad->enable_mask = 0x3;
+
+ omap_clk_register_apll(&clk_hw->hw, node);
+ return;
+
+cleanup:
+ kfree(parent_names);
+ kfree(ad);
+ kfree(clk_hw);
+ kfree(init);
+}
+CLK_OF_DECLARE(dra7_apll_clock, "ti,dra7-apll-clock", of_dra7_apll_setup);
+
+#define OMAP2_EN_APLL_LOCKED 0x3
+#define OMAP2_EN_APLL_STOPPED 0x0
+
+static int omap2_apll_is_enabled(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ struct dpll_data *ad = clk->dpll_data;
+ u32 v;
+
+ v = ti_clk_ll_ops->clk_readl(ad->control_reg);
+ v &= ad->enable_mask;
+
+ v >>= __ffs(ad->enable_mask);
+
+ return v == OMAP2_EN_APLL_LOCKED ? 1 : 0;
+}
+
+static unsigned long omap2_apll_recalc(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+
+ if (omap2_apll_is_enabled(hw))
+ return clk->fixed_rate;
+
+ return 0;
+}
+
+static int omap2_apll_enable(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ struct dpll_data *ad = clk->dpll_data;
+ u32 v;
+ int i = 0;
+
+ v = ti_clk_ll_ops->clk_readl(ad->control_reg);
+ v &= ~ad->enable_mask;
+ v |= OMAP2_EN_APLL_LOCKED << __ffs(ad->enable_mask);
+ ti_clk_ll_ops->clk_writel(v, ad->control_reg);
+
+ while (1) {
+ v = ti_clk_ll_ops->clk_readl(ad->idlest_reg);
+ if (v & ad->idlest_mask)
+ break;
+ if (i > MAX_APLL_WAIT_TRIES)
+ break;
+ i++;
+ udelay(1);
+ }
+
+ if (i == MAX_APLL_WAIT_TRIES) {
+ pr_warn("%s failed to transition to locked\n",
+ __clk_get_name(clk->hw.clk));
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
+static void omap2_apll_disable(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ struct dpll_data *ad = clk->dpll_data;
+ u32 v;
+
+ v = ti_clk_ll_ops->clk_readl(ad->control_reg);
+ v &= ~ad->enable_mask;
+ v |= OMAP2_EN_APLL_STOPPED << __ffs(ad->enable_mask);
+ ti_clk_ll_ops->clk_writel(v, ad->control_reg);
+}
+
+static struct clk_ops omap2_apll_ops = {
+ .enable = &omap2_apll_enable,
+ .disable = &omap2_apll_disable,
+ .is_enabled = &omap2_apll_is_enabled,
+ .recalc_rate = &omap2_apll_recalc,
+};
+
+static void omap2_apll_set_autoidle(struct clk_hw_omap *clk, u32 val)
+{
+ struct dpll_data *ad = clk->dpll_data;
+ u32 v;
+
+ v = ti_clk_ll_ops->clk_readl(ad->autoidle_reg);
+ v &= ~ad->autoidle_mask;
+ v |= val << __ffs(ad->autoidle_mask);
+ ti_clk_ll_ops->clk_writel(v, ad->control_reg);
+}
+
+#define OMAP2_APLL_AUTOIDLE_LOW_POWER_STOP 0x3
+#define OMAP2_APLL_AUTOIDLE_DISABLE 0x0
+
+static void omap2_apll_allow_idle(struct clk_hw_omap *clk)
+{
+ omap2_apll_set_autoidle(clk, OMAP2_APLL_AUTOIDLE_LOW_POWER_STOP);
+}
+
+static void omap2_apll_deny_idle(struct clk_hw_omap *clk)
+{
+ omap2_apll_set_autoidle(clk, OMAP2_APLL_AUTOIDLE_DISABLE);
+}
+
+static struct clk_hw_omap_ops omap2_apll_hwops = {
+ .allow_idle = &omap2_apll_allow_idle,
+ .deny_idle = &omap2_apll_deny_idle,
+};
+
+static void __init of_omap2_apll_setup(struct device_node *node)
+{
+ struct dpll_data *ad = NULL;
+ struct clk_hw_omap *clk_hw = NULL;
+ struct clk_init_data *init = NULL;
+ struct clk *clk;
+ const char *parent_name;
+ u32 val;
+
+ ad = kzalloc(sizeof(*ad), GFP_KERNEL);
+ clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL);
+ init = kzalloc(sizeof(*init), GFP_KERNEL);
+
+ if (!ad || !clk_hw || !init)
+ goto cleanup;
+
+ clk_hw->dpll_data = ad;
+ clk_hw->hw.init = init;
+ init->ops = &omap2_apll_ops;
+ init->name = node->name;
+ clk_hw->ops = &omap2_apll_hwops;
+
+ init->num_parents = of_clk_get_parent_count(node);
+ if (init->num_parents != 1) {
+ pr_err("%s must have one parent\n", node->name);
+ goto cleanup;
+ }
+
+ parent_name = of_clk_get_parent_name(node, 0);
+ init->parent_names = &parent_name;
+
+ if (of_property_read_u32(node, "ti,clock-frequency", &val)) {
+ pr_err("%s missing clock-frequency\n", node->name);
+ goto cleanup;
+ }
+ clk_hw->fixed_rate = val;
+
+ if (of_property_read_u32(node, "ti,bit-shift", &val)) {
+ pr_err("%s missing bit-shift\n", node->name);
+ goto cleanup;
+ }
+
+ clk_hw->enable_bit = val;
+ ad->enable_mask = 0x3 << val;
+ ad->autoidle_mask = 0x3 << val;
+
+ if (of_property_read_u32(node, "ti,idlest-shift", &val)) {
+ pr_err("%s missing idlest-shift\n", node->name);
+ goto cleanup;
+ }
+
+ ad->idlest_mask = 1 << val;
+
+ ad->control_reg = ti_clk_get_reg_addr(node, 0);
+ ad->autoidle_reg = ti_clk_get_reg_addr(node, 1);
+ ad->idlest_reg = ti_clk_get_reg_addr(node, 2);
+
+ if (IS_ERR(ad->control_reg) || IS_ERR(ad->autoidle_reg) ||
+ IS_ERR(ad->idlest_reg))
+ goto cleanup;
+
+ clk = clk_register(NULL, &clk_hw->hw);
+ if (!IS_ERR(clk)) {
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ kfree(init);
+ return;
+ }
+cleanup:
+ kfree(ad);
+ kfree(clk_hw);
+ kfree(init);
+}
+CLK_OF_DECLARE(omap2_apll_clock, "ti,omap2-apll-clock",
+ of_omap2_apll_setup);
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