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-rw-r--r--drivers/clk/ti/clk.c520
1 files changed, 520 insertions, 0 deletions
diff --git a/drivers/clk/ti/clk.c b/drivers/clk/ti/clk.c
new file mode 100644
index 000000000..0cc87c6ae
--- /dev/null
+++ b/drivers/clk/ti/clk.c
@@ -0,0 +1,520 @@
+/*
+ * TI clock support
+ *
+ * Copyright (C) 2013 Texas Instruments, Inc.
+ *
+ * Tero Kristo <t-kristo@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.h>
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/ti.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/list.h>
+#include <linux/regmap.h>
+#include <linux/bootmem.h>
+#include <linux/device.h>
+
+#include "clock.h"
+
+#undef pr_fmt
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+struct ti_clk_ll_ops *ti_clk_ll_ops;
+static struct device_node *clocks_node_ptr[CLK_MAX_MEMMAPS];
+
+static struct ti_clk_features ti_clk_features;
+
+struct clk_iomap {
+ struct regmap *regmap;
+ void __iomem *mem;
+};
+
+static struct clk_iomap *clk_memmaps[CLK_MAX_MEMMAPS];
+
+static void clk_memmap_writel(u32 val, const struct clk_omap_reg *reg)
+{
+ struct clk_iomap *io = clk_memmaps[reg->index];
+
+ if (reg->ptr)
+ writel_relaxed(val, reg->ptr);
+ else if (io->regmap)
+ regmap_write(io->regmap, reg->offset, val);
+ else
+ writel_relaxed(val, io->mem + reg->offset);
+}
+
+static void _clk_rmw(u32 val, u32 mask, void __iomem *ptr)
+{
+ u32 v;
+
+ v = readl_relaxed(ptr);
+ v &= ~mask;
+ v |= val;
+ writel_relaxed(v, ptr);
+}
+
+static void clk_memmap_rmw(u32 val, u32 mask, const struct clk_omap_reg *reg)
+{
+ struct clk_iomap *io = clk_memmaps[reg->index];
+
+ if (reg->ptr) {
+ _clk_rmw(val, mask, reg->ptr);
+ } else if (io->regmap) {
+ regmap_update_bits(io->regmap, reg->offset, mask, val);
+ } else {
+ _clk_rmw(val, mask, io->mem + reg->offset);
+ }
+}
+
+static u32 clk_memmap_readl(const struct clk_omap_reg *reg)
+{
+ u32 val;
+ struct clk_iomap *io = clk_memmaps[reg->index];
+
+ if (reg->ptr)
+ val = readl_relaxed(reg->ptr);
+ else if (io->regmap)
+ regmap_read(io->regmap, reg->offset, &val);
+ else
+ val = readl_relaxed(io->mem + reg->offset);
+
+ return val;
+}
+
+/**
+ * ti_clk_setup_ll_ops - setup low level clock operations
+ * @ops: low level clock ops descriptor
+ *
+ * Sets up low level clock operations for TI clock driver. This is used
+ * to provide various callbacks for the clock driver towards platform
+ * specific code. Returns 0 on success, -EBUSY if ll_ops have been
+ * registered already.
+ */
+int ti_clk_setup_ll_ops(struct ti_clk_ll_ops *ops)
+{
+ if (ti_clk_ll_ops) {
+ pr_err("Attempt to register ll_ops multiple times.\n");
+ return -EBUSY;
+ }
+
+ ti_clk_ll_ops = ops;
+ ops->clk_readl = clk_memmap_readl;
+ ops->clk_writel = clk_memmap_writel;
+ ops->clk_rmw = clk_memmap_rmw;
+
+ return 0;
+}
+
+/**
+ * ti_dt_clocks_register - register DT alias clocks during boot
+ * @oclks: list of clocks to register
+ *
+ * Register alias or non-standard DT clock entries during boot. By
+ * default, DT clocks are found based on their node name. If any
+ * additional con-id / dev-id -> clock mapping is required, use this
+ * function to list these.
+ */
+void __init ti_dt_clocks_register(struct ti_dt_clk oclks[])
+{
+ struct ti_dt_clk *c;
+ struct device_node *node, *parent;
+ struct clk *clk;
+ struct of_phandle_args clkspec;
+ char buf[64];
+ char *ptr;
+ char *tags[2];
+ int i;
+ int num_args;
+ int ret;
+ static bool clkctrl_nodes_missing;
+ static bool has_clkctrl_data;
+
+ for (c = oclks; c->node_name != NULL; c++) {
+ strcpy(buf, c->node_name);
+ ptr = buf;
+ for (i = 0; i < 2; i++)
+ tags[i] = NULL;
+ num_args = 0;
+ while (*ptr) {
+ if (*ptr == ':') {
+ if (num_args >= 2) {
+ pr_warn("Bad number of tags on %s\n",
+ c->node_name);
+ return;
+ }
+ tags[num_args++] = ptr + 1;
+ *ptr = 0;
+ }
+ ptr++;
+ }
+
+ if (num_args && clkctrl_nodes_missing)
+ continue;
+
+ node = of_find_node_by_name(NULL, buf);
+ if (num_args) {
+ parent = node;
+ node = of_get_child_by_name(parent, "clk");
+ of_node_put(parent);
+ }
+
+ clkspec.np = node;
+ clkspec.args_count = num_args;
+ for (i = 0; i < num_args; i++) {
+ ret = kstrtoint(tags[i], i ? 10 : 16, clkspec.args + i);
+ if (ret) {
+ pr_warn("Bad tag in %s at %d: %s\n",
+ c->node_name, i, tags[i]);
+ of_node_put(node);
+ return;
+ }
+ }
+ clk = of_clk_get_from_provider(&clkspec);
+ of_node_put(node);
+ if (!IS_ERR(clk)) {
+ c->lk.clk = clk;
+ clkdev_add(&c->lk);
+ } else {
+ if (num_args && !has_clkctrl_data) {
+ struct device_node *np;
+
+ np = of_find_compatible_node(NULL, NULL,
+ "ti,clkctrl");
+ if (np) {
+ has_clkctrl_data = true;
+ of_node_put(np);
+ } else {
+ clkctrl_nodes_missing = true;
+
+ pr_warn("missing clkctrl nodes, please update your dts.\n");
+ continue;
+ }
+ }
+
+ pr_warn("failed to lookup clock node %s, ret=%ld\n",
+ c->node_name, PTR_ERR(clk));
+ }
+ }
+}
+
+struct clk_init_item {
+ struct device_node *node;
+ void *user;
+ ti_of_clk_init_cb_t func;
+ struct list_head link;
+};
+
+static LIST_HEAD(retry_list);
+
+/**
+ * ti_clk_retry_init - retries a failed clock init at later phase
+ * @node: device not for the clock
+ * @user: user data pointer
+ * @func: init function to be called for the clock
+ *
+ * Adds a failed clock init to the retry list. The retry list is parsed
+ * once all the other clocks have been initialized.
+ */
+int __init ti_clk_retry_init(struct device_node *node, void *user,
+ ti_of_clk_init_cb_t func)
+{
+ struct clk_init_item *retry;
+
+ pr_debug("%s: adding to retry list...\n", node->name);
+ retry = kzalloc(sizeof(*retry), GFP_KERNEL);
+ if (!retry)
+ return -ENOMEM;
+
+ retry->node = node;
+ retry->func = func;
+ retry->user = user;
+ list_add(&retry->link, &retry_list);
+
+ return 0;
+}
+
+/**
+ * ti_clk_get_reg_addr - get register address for a clock register
+ * @node: device node for the clock
+ * @index: register index from the clock node
+ * @reg: pointer to target register struct
+ *
+ * Builds clock register address from device tree information, and returns
+ * the data via the provided output pointer @reg. Returns 0 on success,
+ * negative error value on failure.
+ */
+int ti_clk_get_reg_addr(struct device_node *node, int index,
+ struct clk_omap_reg *reg)
+{
+ u32 val;
+ int i;
+
+ for (i = 0; i < CLK_MAX_MEMMAPS; i++) {
+ if (clocks_node_ptr[i] == node->parent)
+ break;
+ }
+
+ if (i == CLK_MAX_MEMMAPS) {
+ pr_err("clk-provider not found for %s!\n", node->name);
+ return -ENOENT;
+ }
+
+ reg->index = i;
+
+ if (of_property_read_u32_index(node, "reg", index, &val)) {
+ pr_err("%s must have reg[%d]!\n", node->name, index);
+ return -EINVAL;
+ }
+
+ reg->offset = val;
+ reg->ptr = NULL;
+
+ return 0;
+}
+
+void ti_clk_latch(struct clk_omap_reg *reg, s8 shift)
+{
+ u32 latch;
+
+ if (shift < 0)
+ return;
+
+ latch = 1 << shift;
+
+ ti_clk_ll_ops->clk_rmw(latch, latch, reg);
+ ti_clk_ll_ops->clk_rmw(0, latch, reg);
+ ti_clk_ll_ops->clk_readl(reg); /* OCP barrier */
+}
+
+/**
+ * omap2_clk_provider_init - init master clock provider
+ * @parent: master node
+ * @index: internal index for clk_reg_ops
+ * @syscon: syscon regmap pointer for accessing clock registers
+ * @mem: iomem pointer for the clock provider memory area, only used if
+ * syscon is not provided
+ *
+ * Initializes a master clock IP block. This basically sets up the
+ * mapping from clocks node to the memory map index. All the clocks
+ * are then initialized through the common of_clk_init call, and the
+ * clocks will access their memory maps based on the node layout.
+ * Returns 0 in success.
+ */
+int __init omap2_clk_provider_init(struct device_node *parent, int index,
+ struct regmap *syscon, void __iomem *mem)
+{
+ struct device_node *clocks;
+ struct clk_iomap *io;
+
+ /* get clocks for this parent */
+ clocks = of_get_child_by_name(parent, "clocks");
+ if (!clocks) {
+ pr_err("%s missing 'clocks' child node.\n", parent->name);
+ return -EINVAL;
+ }
+
+ /* add clocks node info */
+ clocks_node_ptr[index] = clocks;
+
+ io = kzalloc(sizeof(*io), GFP_KERNEL);
+ if (!io)
+ return -ENOMEM;
+
+ io->regmap = syscon;
+ io->mem = mem;
+
+ clk_memmaps[index] = io;
+
+ return 0;
+}
+
+/**
+ * omap2_clk_legacy_provider_init - initialize a legacy clock provider
+ * @index: index for the clock provider
+ * @mem: iomem pointer for the clock provider memory area
+ *
+ * Initializes a legacy clock provider memory mapping.
+ */
+void __init omap2_clk_legacy_provider_init(int index, void __iomem *mem)
+{
+ struct clk_iomap *io;
+
+ io = memblock_virt_alloc(sizeof(*io), 0);
+
+ io->mem = mem;
+
+ clk_memmaps[index] = io;
+}
+
+/**
+ * ti_dt_clk_init_retry_clks - init clocks from the retry list
+ *
+ * Initializes any clocks that have failed to initialize before,
+ * reasons being missing parent node(s) during earlier init. This
+ * typically happens only for DPLLs which need to have both of their
+ * parent clocks ready during init.
+ */
+void ti_dt_clk_init_retry_clks(void)
+{
+ struct clk_init_item *retry;
+ struct clk_init_item *tmp;
+ int retries = 5;
+
+ while (!list_empty(&retry_list) && retries) {
+ list_for_each_entry_safe(retry, tmp, &retry_list, link) {
+ pr_debug("retry-init: %s\n", retry->node->name);
+ retry->func(retry->user, retry->node);
+ list_del(&retry->link);
+ kfree(retry);
+ }
+ retries--;
+ }
+}
+
+static const struct of_device_id simple_clk_match_table[] __initconst = {
+ { .compatible = "fixed-clock" },
+ { .compatible = "fixed-factor-clock" },
+ { }
+};
+
+/**
+ * ti_clk_add_aliases - setup clock aliases
+ *
+ * Sets up any missing clock aliases. No return value.
+ */
+void __init ti_clk_add_aliases(void)
+{
+ struct device_node *np;
+ struct clk *clk;
+
+ for_each_matching_node(np, simple_clk_match_table) {
+ struct of_phandle_args clkspec;
+
+ clkspec.np = np;
+ clk = of_clk_get_from_provider(&clkspec);
+
+ ti_clk_add_alias(NULL, clk, np->name);
+ }
+}
+
+/**
+ * ti_clk_setup_features - setup clock features flags
+ * @features: features definition to use
+ *
+ * Initializes the clock driver features flags based on platform
+ * provided data. No return value.
+ */
+void __init ti_clk_setup_features(struct ti_clk_features *features)
+{
+ memcpy(&ti_clk_features, features, sizeof(*features));
+}
+
+/**
+ * ti_clk_get_features - get clock driver features flags
+ *
+ * Get TI clock driver features description. Returns a pointer
+ * to the current feature setup.
+ */
+const struct ti_clk_features *ti_clk_get_features(void)
+{
+ return &ti_clk_features;
+}
+
+/**
+ * omap2_clk_enable_init_clocks - prepare & enable a list of clocks
+ * @clk_names: ptr to an array of strings of clock names to enable
+ * @num_clocks: number of clock names in @clk_names
+ *
+ * Prepare and enable a list of clocks, named by @clk_names. No
+ * return value. XXX Deprecated; only needed until these clocks are
+ * properly claimed and enabled by the drivers or core code that uses
+ * them. XXX What code disables & calls clk_put on these clocks?
+ */
+void omap2_clk_enable_init_clocks(const char **clk_names, u8 num_clocks)
+{
+ struct clk *init_clk;
+ int i;
+
+ for (i = 0; i < num_clocks; i++) {
+ init_clk = clk_get(NULL, clk_names[i]);
+ if (WARN(IS_ERR(init_clk), "could not find init clock %s\n",
+ clk_names[i]))
+ continue;
+ clk_prepare_enable(init_clk);
+ }
+}
+
+/**
+ * ti_clk_add_alias - add a clock alias for a TI clock
+ * @dev: device alias for this clock
+ * @clk: clock handle to create alias for
+ * @con: connection ID for this clock
+ *
+ * Creates a clock alias for a TI clock. Allocates the clock lookup entry
+ * and assigns the data to it. Returns 0 if successful, negative error
+ * value otherwise.
+ */
+int ti_clk_add_alias(struct device *dev, struct clk *clk, const char *con)
+{
+ struct clk_lookup *cl;
+
+ if (!clk)
+ return 0;
+
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ cl = kzalloc(sizeof(*cl), GFP_KERNEL);
+ if (!cl)
+ return -ENOMEM;
+
+ if (dev)
+ cl->dev_id = dev_name(dev);
+ cl->con_id = con;
+ cl->clk = clk;
+
+ clkdev_add(cl);
+
+ return 0;
+}
+
+/**
+ * ti_clk_register - register a TI clock to the common clock framework
+ * @dev: device for this clock
+ * @hw: hardware clock handle
+ * @con: connection ID for this clock
+ *
+ * Registers a TI clock to the common clock framework, and adds a clock
+ * alias for it. Returns a handle to the registered clock if successful,
+ * ERR_PTR value in failure.
+ */
+struct clk *ti_clk_register(struct device *dev, struct clk_hw *hw,
+ const char *con)
+{
+ struct clk *clk;
+ int ret;
+
+ clk = clk_register(dev, hw);
+ if (IS_ERR(clk))
+ return clk;
+
+ ret = ti_clk_add_alias(dev, clk, con);
+ if (ret) {
+ clk_unregister(clk);
+ return ERR_PTR(ret);
+ }
+
+ return clk;
+}