diff options
author | Stephen Boyd <sboyd@kernel.org> | 2019-05-07 11:46:13 -0700 |
---|---|---|
committer | Stephen Boyd <sboyd@kernel.org> | 2019-05-07 11:46:13 -0700 |
commit | c1157f60d72e8b20efc670cef28883832f42406c (patch) | |
tree | e12b4aa8986f184cbf5a92a1816c210c23fdbbc9 /drivers/clk | |
parent | 0caf000817353cfc5db22363ecdac63b83d3a3f9 (diff) | |
parent | 1a079560b1450b72ff4e944bb9185e77633d74c4 (diff) |
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/clk')
-rw-r--r-- | drivers/clk/clk-fixed-factor.c | 55 | ||||
-rw-r--r-- | drivers/clk/clk.c | 353 | ||||
-rw-r--r-- | drivers/clk/clk.h | 2 | ||||
-rw-r--r-- | drivers/clk/clkdev.c | 25 |
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) |