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authorStephen Boyd <sboyd@kernel.org>2019-05-07 20:46:13 +0200
committerStephen Boyd <sboyd@kernel.org>2019-05-07 20:46:13 +0200
commitc1157f60d72e8b20efc670cef28883832f42406c (patch)
treee12b4aa8986f184cbf5a92a1816c210c23fdbbc9 /drivers
parentMerge branch 'clk-ti' into clk-next (diff)
parentclk: Cache core in clk_fetch_parent_index() without names (diff)
downloadlinux-c1157f60d72e8b20efc670cef28883832f42406c.tar.xz
linux-c1157f60d72e8b20efc670cef28883832f42406c.zip
Merge branch 'clk-parent-rewrite-1' into clk-next
- Rewrite how clk parents can be specified to be DT/clkdev based instead of just string based * clk-parent-rewrite-1: clk: Cache core in clk_fetch_parent_index() without names clk: fixed-factor: Initialize clk_init_data on stack clk: fixed-factor: Let clk framework find parent clk: Allow parents to be specified via clkspec index clk: Look for parents with clkdev based clk_lookups clk: Allow parents to be specified without string names clk: Add of_clk_hw_register() API for early clk drivers driver core: Let dev_of_node() accept a NULL dev clk: Prepare for clk registration API that uses DT nodes clkdev: Move clk creation outside of 'clocks_mutex'
Diffstat (limited to 'drivers')
-rw-r--r--drivers/clk/clk-fixed-factor.c55
-rw-r--r--drivers/clk/clk.c353
-rw-r--r--drivers/clk/clk.h2
-rw-r--r--drivers/clk/clkdev.c25
4 files changed, 322 insertions, 113 deletions
diff --git a/drivers/clk/clk-fixed-factor.c b/drivers/clk/clk-fixed-factor.c
index 8aac2d1b6fea..8b343e59dc61 100644
--- a/drivers/clk/clk-fixed-factor.c
+++ b/drivers/clk/clk-fixed-factor.c
@@ -64,12 +64,14 @@ const struct clk_ops clk_fixed_factor_ops = {
};
EXPORT_SYMBOL_GPL(clk_fixed_factor_ops);
-struct clk_hw *clk_hw_register_fixed_factor(struct device *dev,
- const char *name, const char *parent_name, unsigned long flags,
- unsigned int mult, unsigned int div)
+static struct clk_hw *
+__clk_hw_register_fixed_factor(struct device *dev, struct device_node *np,
+ const char *name, const char *parent_name, int index,
+ unsigned long flags, unsigned int mult, unsigned int div)
{
struct clk_fixed_factor *fix;
- struct clk_init_data init;
+ struct clk_init_data init = { };
+ struct clk_parent_data pdata = { .index = index };
struct clk_hw *hw;
int ret;
@@ -85,11 +87,17 @@ struct clk_hw *clk_hw_register_fixed_factor(struct device *dev,
init.name = name;
init.ops = &clk_fixed_factor_ops;
init.flags = flags;
- init.parent_names = &parent_name;
+ if (parent_name)
+ init.parent_names = &parent_name;
+ else
+ init.parent_data = &pdata;
init.num_parents = 1;
hw = &fix->hw;
- ret = clk_hw_register(dev, hw);
+ if (dev)
+ ret = clk_hw_register(dev, hw);
+ else
+ ret = of_clk_hw_register(np, hw);
if (ret) {
kfree(fix);
hw = ERR_PTR(ret);
@@ -97,6 +105,14 @@ struct clk_hw *clk_hw_register_fixed_factor(struct device *dev,
return hw;
}
+
+struct clk_hw *clk_hw_register_fixed_factor(struct device *dev,
+ const char *name, const char *parent_name, unsigned long flags,
+ unsigned int mult, unsigned int div)
+{
+ return __clk_hw_register_fixed_factor(dev, NULL, name, parent_name, -1,
+ flags, mult, div);
+}
EXPORT_SYMBOL_GPL(clk_hw_register_fixed_factor);
struct clk *clk_register_fixed_factor(struct device *dev, const char *name,
@@ -143,11 +159,10 @@ static const struct of_device_id set_rate_parent_matches[] = {
{ /* Sentinel */ },
};
-static struct clk *_of_fixed_factor_clk_setup(struct device_node *node)
+static struct clk_hw *_of_fixed_factor_clk_setup(struct device_node *node)
{
- struct clk *clk;
+ struct clk_hw *hw;
const char *clk_name = node->name;
- const char *parent_name;
unsigned long flags = 0;
u32 div, mult;
int ret;
@@ -165,30 +180,28 @@ static struct clk *_of_fixed_factor_clk_setup(struct device_node *node)
}
of_property_read_string(node, "clock-output-names", &clk_name);
- parent_name = of_clk_get_parent_name(node, 0);
if (of_match_node(set_rate_parent_matches, node))
flags |= CLK_SET_RATE_PARENT;
- clk = clk_register_fixed_factor(NULL, clk_name, parent_name, flags,
- mult, div);
- if (IS_ERR(clk)) {
+ hw = __clk_hw_register_fixed_factor(NULL, node, clk_name, NULL, 0,
+ flags, mult, div);
+ if (IS_ERR(hw)) {
/*
- * If parent clock is not registered, registration would fail.
* Clear OF_POPULATED flag so that clock registration can be
* attempted again from probe function.
*/
of_node_clear_flag(node, OF_POPULATED);
- return clk;
+ return ERR_CAST(hw);
}
- ret = of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get, hw);
if (ret) {
- clk_unregister(clk);
+ clk_hw_unregister_fixed_factor(hw);
return ERR_PTR(ret);
}
- return clk;
+ return hw;
}
/**
@@ -203,17 +216,17 @@ CLK_OF_DECLARE(fixed_factor_clk, "fixed-factor-clock",
static int of_fixed_factor_clk_remove(struct platform_device *pdev)
{
- struct clk *clk = platform_get_drvdata(pdev);
+ struct clk_hw *clk = platform_get_drvdata(pdev);
of_clk_del_provider(pdev->dev.of_node);
- clk_unregister_fixed_factor(clk);
+ clk_hw_unregister_fixed_factor(clk);
return 0;
}
static int of_fixed_factor_clk_probe(struct platform_device *pdev)
{
- struct clk *clk;
+ struct clk_hw *clk;
/*
* This function is not executed when of_fixed_factor_clk_setup
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 3e1708747cd2..aa51756fd4d6 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -39,15 +39,23 @@ static LIST_HEAD(clk_notifier_list);
/*** private data structures ***/
+struct clk_parent_map {
+ const struct clk_hw *hw;
+ struct clk_core *core;
+ const char *fw_name;
+ const char *name;
+ int index;
+};
+
struct clk_core {
const char *name;
const struct clk_ops *ops;
struct clk_hw *hw;
struct module *owner;
struct device *dev;
+ struct device_node *of_node;
struct clk_core *parent;
- const char **parent_names;
- struct clk_core **parents;
+ struct clk_parent_map *parents;
u8 num_parents;
u8 new_parent_index;
unsigned long rate;
@@ -316,17 +324,102 @@ static struct clk_core *clk_core_lookup(const char *name)
return NULL;
}
+/**
+ * clk_core_get - Find the clk_core parent of a clk
+ * @core: clk to find parent of
+ * @p_index: parent index to search for
+ *
+ * This is the preferred method for clk providers to find the parent of a
+ * clk when that parent is external to the clk controller. The parent_names
+ * array is indexed and treated as a local name matching a string in the device
+ * node's 'clock-names' property or as the 'con_id' matching the device's
+ * dev_name() in a clk_lookup. This allows clk providers to use their own
+ * namespace instead of looking for a globally unique parent string.
+ *
+ * For example the following DT snippet would allow a clock registered by the
+ * clock-controller@c001 that has a clk_init_data::parent_data array
+ * with 'xtal' in the 'name' member to find the clock provided by the
+ * clock-controller@f00abcd without needing to get the globally unique name of
+ * the xtal clk.
+ *
+ * parent: clock-controller@f00abcd {
+ * reg = <0xf00abcd 0xabcd>;
+ * #clock-cells = <0>;
+ * };
+ *
+ * clock-controller@c001 {
+ * reg = <0xc001 0xf00d>;
+ * clocks = <&parent>;
+ * clock-names = "xtal";
+ * #clock-cells = <1>;
+ * };
+ *
+ * Returns: -ENOENT when the provider can't be found or the clk doesn't
+ * exist in the provider. -EINVAL when the name can't be found. NULL when the
+ * provider knows about the clk but it isn't provided on this system.
+ * A valid clk_core pointer when the clk can be found in the provider.
+ */
+static struct clk_core *clk_core_get(struct clk_core *core, u8 p_index)
+{
+ const char *name = core->parents[p_index].fw_name;
+ int index = core->parents[p_index].index;
+ struct clk_hw *hw = ERR_PTR(-ENOENT);
+ struct device *dev = core->dev;
+ const char *dev_id = dev ? dev_name(dev) : NULL;
+ struct device_node *np = core->of_node;
+
+ if (np && index >= 0)
+ hw = of_clk_get_hw(np, index, name);
+
+ /*
+ * If the DT search above couldn't find the provider or the provider
+ * didn't know about this clk, fallback to looking up via clkdev based
+ * clk_lookups
+ */
+ if (PTR_ERR(hw) == -ENOENT && name)
+ hw = clk_find_hw(dev_id, name);
+
+ if (IS_ERR(hw))
+ return ERR_CAST(hw);
+
+ return hw->core;
+}
+
+static void clk_core_fill_parent_index(struct clk_core *core, u8 index)
+{
+ struct clk_parent_map *entry = &core->parents[index];
+ struct clk_core *parent = ERR_PTR(-ENOENT);
+
+ if (entry->hw) {
+ parent = entry->hw->core;
+ /*
+ * We have a direct reference but it isn't registered yet?
+ * Orphan it and let clk_reparent() update the orphan status
+ * when the parent is registered.
+ */
+ if (!parent)
+ parent = ERR_PTR(-EPROBE_DEFER);
+ } else {
+ parent = clk_core_get(core, index);
+ if (IS_ERR(parent) && PTR_ERR(parent) == -ENOENT)
+ parent = clk_core_lookup(entry->name);
+ }
+
+ /* Only cache it if it's not an error */
+ if (!IS_ERR(parent))
+ entry->core = parent;
+}
+
static struct clk_core *clk_core_get_parent_by_index(struct clk_core *core,
u8 index)
{
- if (!core || index >= core->num_parents)
+ if (!core || index >= core->num_parents || !core->parents)
return NULL;
- if (!core->parents[index])
- core->parents[index] =
- clk_core_lookup(core->parent_names[index]);
+ if (!core->parents[index].core)
+ clk_core_fill_parent_index(core, index);
- return core->parents[index];
+ return core->parents[index].core;
}
struct clk_hw *
@@ -1520,20 +1613,37 @@ static int clk_fetch_parent_index(struct clk_core *core,
return -EINVAL;
for (i = 0; i < core->num_parents; i++) {
- if (core->parents[i] == parent)
+ /* Found it first try! */
+ if (core->parents[i].core == parent)
return i;
- if (core->parents[i])
+ /* Something else is here, so keep looking */
+ if (core->parents[i].core)
continue;
- /* Fallback to comparing globally unique names */
- if (!strcmp(parent->name, core->parent_names[i])) {
- core->parents[i] = parent;
- return i;
+ /* Maybe core hasn't been cached but the hw is all we know? */
+ if (core->parents[i].hw) {
+ if (core->parents[i].hw == parent->hw)
+ break;
+
+ /* Didn't match, but we're expecting a clk_hw */
+ continue;
}
+
+ /* Maybe it hasn't been cached (clk_set_parent() path) */
+ if (parent == clk_core_get(core, i))
+ break;
+
+ /* Fallback to comparing globally unique names */
+ if (!strcmp(parent->name, core->parents[i].name))
+ break;
}
- return -EINVAL;
+ if (i == core->num_parents)
+ return -EINVAL;
+
+ core->parents[i].core = parent;
+ return i;
}
/*
@@ -2294,6 +2404,7 @@ void clk_hw_reparent(struct clk_hw *hw, struct clk_hw *new_parent)
bool clk_has_parent(struct clk *clk, struct clk *parent)
{
struct clk_core *core, *parent_core;
+ int i;
/* NULL clocks should be nops, so return success if either is NULL. */
if (!clk || !parent)
@@ -2306,8 +2417,11 @@ bool clk_has_parent(struct clk *clk, struct clk *parent)
if (core->parent == parent_core)
return true;
- return match_string(core->parent_names, core->num_parents,
- parent_core->name) >= 0;
+ for (i = 0; i < core->num_parents; i++)
+ if (!strcmp(core->parents[i].name, parent_core->name))
+ return true;
+
+ return false;
}
EXPORT_SYMBOL_GPL(clk_has_parent);
@@ -2889,9 +3003,9 @@ static int possible_parents_show(struct seq_file *s, void *data)
int i;
for (i = 0; i < core->num_parents - 1; i++)
- seq_printf(s, "%s ", core->parent_names[i]);
+ seq_printf(s, "%s ", core->parents[i].name);
- seq_printf(s, "%s\n", core->parent_names[i]);
+ seq_printf(s, "%s\n", core->parents[i].name);
return 0;
}
@@ -3025,7 +3139,7 @@ static inline void clk_debug_unregister(struct clk_core *core)
*/
static int __clk_core_init(struct clk_core *core)
{
- int i, ret;
+ int ret;
struct clk_core *orphan;
struct hlist_node *tmp2;
unsigned long rate;
@@ -3079,12 +3193,6 @@ static int __clk_core_init(struct clk_core *core)
goto out;
}
- /* throw a WARN if any entries in parent_names are NULL */
- for (i = 0; i < core->num_parents; i++)
- WARN(!core->parent_names[i],
- "%s: invalid NULL in %s's .parent_names\n",
- __func__, core->name);
-
core->parent = __clk_init_parent(core);
/*
@@ -3313,22 +3421,104 @@ struct clk *clk_hw_create_clk(struct device *dev, struct clk_hw *hw,
return clk;
}
-/**
- * clk_register - allocate a new clock, register it and return an opaque cookie
- * @dev: device that is registering this clock
- * @hw: link to hardware-specific clock data
- *
- * clk_register is the *deprecated* interface for populating the clock tree with
- * new clock nodes. Use clk_hw_register() instead.
- *
- * Returns: a pointer to the newly allocated struct clk which
- * cannot be dereferenced by driver code but may be used in conjunction with the
- * rest of the clock API. In the event of an error clk_register will return an
- * error code; drivers must test for an error code after calling clk_register.
- */
-struct clk *clk_register(struct device *dev, struct clk_hw *hw)
+static int clk_cpy_name(const char **dst_p, const char *src, bool must_exist)
{
- int i, ret;
+ const char *dst;
+
+ if (!src) {
+ if (must_exist)
+ return -EINVAL;
+ return 0;
+ }
+
+ *dst_p = dst = kstrdup_const(src, GFP_KERNEL);
+ if (!dst)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static int clk_core_populate_parent_map(struct clk_core *core)
+{
+ const struct clk_init_data *init = core->hw->init;
+ u8 num_parents = init->num_parents;
+ const char * const *parent_names = init->parent_names;
+ const struct clk_hw **parent_hws = init->parent_hws;
+ const struct clk_parent_data *parent_data = init->parent_data;
+ int i, ret = 0;
+ struct clk_parent_map *parents, *parent;
+
+ if (!num_parents)
+ return 0;
+
+ /*
+ * Avoid unnecessary string look-ups of clk_core's possible parents by
+ * having a cache of names/clk_hw pointers to clk_core pointers.
+ */
+ parents = kcalloc(num_parents, sizeof(*parents), GFP_KERNEL);
+ core->parents = parents;
+ if (!parents)
+ return -ENOMEM;
+
+ /* Copy everything over because it might be __initdata */
+ for (i = 0, parent = parents; i < num_parents; i++, parent++) {
+ parent->index = -1;
+ if (parent_names) {
+ /* throw a WARN if any entries are NULL */
+ WARN(!parent_names[i],
+ "%s: invalid NULL in %s's .parent_names\n",
+ __func__, core->name);
+ ret = clk_cpy_name(&parent->name, parent_names[i],
+ true);
+ } else if (parent_data) {
+ parent->hw = parent_data[i].hw;
+ parent->index = parent_data[i].index;
+ ret = clk_cpy_name(&parent->fw_name,
+ parent_data[i].fw_name, false);
+ if (!ret)
+ ret = clk_cpy_name(&parent->name,
+ parent_data[i].name,
+ false);
+ } else if (parent_hws) {
+ parent->hw = parent_hws[i];
+ } else {
+ ret = -EINVAL;
+ WARN(1, "Must specify parents if num_parents > 0\n");
+ }
+
+ if (ret) {
+ do {
+ kfree_const(parents[i].name);
+ kfree_const(parents[i].fw_name);
+ } while (--i >= 0);
+ kfree(parents);
+
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static void clk_core_free_parent_map(struct clk_core *core)
+{
+ int i = core->num_parents;
+
+ if (!core->num_parents)
+ return;
+
+ while (--i >= 0) {
+ kfree_const(core->parents[i].name);
+ kfree_const(core->parents[i].fw_name);
+ }
+
+ kfree(core->parents);
+}
+
+static struct clk *
+__clk_register(struct device *dev, struct device_node *np, struct clk_hw *hw)
+{
+ int ret;
struct clk_core *core;
core = kzalloc(sizeof(*core), GFP_KERNEL);
@@ -3352,6 +3542,7 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
if (dev && pm_runtime_enabled(dev))
core->rpm_enabled = true;
core->dev = dev;
+ core->of_node = np;
if (dev && dev->driver)
core->owner = dev->driver->owner;
core->hw = hw;
@@ -3361,33 +3552,9 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
core->max_rate = ULONG_MAX;
hw->core = core;
- /* allocate local copy in case parent_names is __initdata */
- core->parent_names = kcalloc(core->num_parents, sizeof(char *),
- GFP_KERNEL);
-
- if (!core->parent_names) {
- ret = -ENOMEM;
- goto fail_parent_names;
- }
-
-
- /* copy each string name in case parent_names is __initdata */
- for (i = 0; i < core->num_parents; i++) {
- core->parent_names[i] = kstrdup_const(hw->init->parent_names[i],
- GFP_KERNEL);
- if (!core->parent_names[i]) {
- ret = -ENOMEM;
- goto fail_parent_names_copy;
- }
- }
-
- /* avoid unnecessary string look-ups of clk_core's possible parents. */
- core->parents = kcalloc(core->num_parents, sizeof(*core->parents),
- GFP_KERNEL);
- if (!core->parents) {
- ret = -ENOMEM;
+ ret = clk_core_populate_parent_map(core);
+ if (ret)
goto fail_parents;
- };
INIT_HLIST_HEAD(&core->clks);
@@ -3398,7 +3565,7 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
hw->clk = alloc_clk(core, NULL, NULL);
if (IS_ERR(hw->clk)) {
ret = PTR_ERR(hw->clk);
- goto fail_parents;
+ goto fail_create_clk;
}
clk_core_link_consumer(hw->core, hw->clk);
@@ -3414,13 +3581,9 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
free_clk(hw->clk);
hw->clk = NULL;
+fail_create_clk:
+ clk_core_free_parent_map(core);
fail_parents:
- kfree(core->parents);
-fail_parent_names_copy:
- while (--i >= 0)
- kfree_const(core->parent_names[i]);
- kfree(core->parent_names);
-fail_parent_names:
fail_ops:
kfree_const(core->name);
fail_name:
@@ -3428,6 +3591,24 @@ fail_name:
fail_out:
return ERR_PTR(ret);
}
+
+/**
+ * clk_register - allocate a new clock, register it and return an opaque cookie
+ * @dev: device that is registering this clock
+ * @hw: link to hardware-specific clock data
+ *
+ * clk_register is the *deprecated* interface for populating the clock tree with
+ * new clock nodes. Use clk_hw_register() instead.
+ *
+ * Returns: a pointer to the newly allocated struct clk which
+ * cannot be dereferenced by driver code but may be used in conjunction with the
+ * rest of the clock API. In the event of an error clk_register will return an
+ * error code; drivers must test for an error code after calling clk_register.
+ */
+struct clk *clk_register(struct device *dev, struct clk_hw *hw)
+{
+ return __clk_register(dev, dev_of_node(dev), hw);
+}
EXPORT_SYMBOL_GPL(clk_register);
/**
@@ -3442,23 +3623,35 @@ EXPORT_SYMBOL_GPL(clk_register);
*/
int clk_hw_register(struct device *dev, struct clk_hw *hw)
{
- return PTR_ERR_OR_ZERO(clk_register(dev, hw));
+ return PTR_ERR_OR_ZERO(__clk_register(dev, dev_of_node(dev), hw));
}
EXPORT_SYMBOL_GPL(clk_hw_register);
+/*
+ * of_clk_hw_register - register a clk_hw and return an error code
+ * @node: device_node of device that is registering this clock
+ * @hw: link to hardware-specific clock data
+ *
+ * of_clk_hw_register() is the primary interface for populating the clock tree
+ * with new clock nodes when a struct device is not available, but a struct
+ * device_node is. It returns an integer equal to zero indicating success or
+ * less than zero indicating failure. Drivers must test for an error code after
+ * calling of_clk_hw_register().
+ */
+int of_clk_hw_register(struct device_node *node, struct clk_hw *hw)
+{
+ return PTR_ERR_OR_ZERO(__clk_register(NULL, node, hw));
+}
+EXPORT_SYMBOL_GPL(of_clk_hw_register);
+
/* Free memory allocated for a clock. */
static void __clk_release(struct kref *ref)
{
struct clk_core *core = container_of(ref, struct clk_core, ref);
- int i = core->num_parents;
lockdep_assert_held(&prepare_lock);
- kfree(core->parents);
- while (--i >= 0)
- kfree_const(core->parent_names[i]);
-
- kfree(core->parent_names);
+ clk_core_free_parent_map(core);
kfree_const(core->name);
kfree(core);
}
diff --git a/drivers/clk/clk.h b/drivers/clk/clk.h
index 553f531cc232..d8400d623b34 100644
--- a/drivers/clk/clk.h
+++ b/drivers/clk/clk.h
@@ -19,6 +19,8 @@ static inline struct clk_hw *of_clk_get_hw(struct device_node *np,
}
#endif
+struct clk_hw *clk_find_hw(const char *dev_id, const char *con_id);
+
#ifdef CONFIG_COMMON_CLK
struct clk *clk_hw_create_clk(struct device *dev, struct clk_hw *hw,
const char *dev_id, const char *con_id);
diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c
index 6e787cc9e5b9..2afc8df8acff 100644
--- a/drivers/clk/clkdev.c
+++ b/drivers/clk/clkdev.c
@@ -72,25 +72,26 @@ static struct clk_lookup *clk_find(const char *dev_id, const char *con_id)
return cl;
}
-static struct clk *__clk_get_sys(struct device *dev, const char *dev_id,
- const char *con_id)
+struct clk_hw *clk_find_hw(const char *dev_id, const char *con_id)
{
struct clk_lookup *cl;
- struct clk *clk = NULL;
+ struct clk_hw *hw = ERR_PTR(-ENOENT);
mutex_lock(&clocks_mutex);
-
cl = clk_find(dev_id, con_id);
- if (!cl)
- goto out;
-
- clk = clk_hw_create_clk(dev, cl->clk_hw, dev_id, con_id);
- if (IS_ERR(clk))
- cl = NULL;
-out:
+ if (cl)
+ hw = cl->clk_hw;
mutex_unlock(&clocks_mutex);
- return cl ? clk : ERR_PTR(-ENOENT);
+ return hw;
+}
+
+static struct clk *__clk_get_sys(struct device *dev, const char *dev_id,
+ const char *con_id)
+{
+ struct clk_hw *hw = clk_find_hw(dev_id, con_id);
+
+ return clk_hw_create_clk(dev, hw, dev_id, con_id);
}
struct clk *clk_get_sys(const char *dev_id, const char *con_id)