diff options
Diffstat (limited to 'drivers/of/base.c')
| -rw-r--r-- | drivers/of/base.c | 166 |
1 files changed, 58 insertions, 108 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c index db7fbc0c0893..ae03b1218b06 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -135,115 +135,38 @@ int __weak of_node_to_nid(struct device_node *np) } #endif -/* - * Assumptions behind phandle_cache implementation: - * - phandle property values are in a contiguous range of 1..n - * - * If the assumptions do not hold, then - * - the phandle lookup overhead reduction provided by the cache - * will likely be less - */ +#define OF_PHANDLE_CACHE_BITS 7 +#define OF_PHANDLE_CACHE_SZ BIT(OF_PHANDLE_CACHE_BITS) -static struct device_node **phandle_cache; -static u32 phandle_cache_mask; +static struct device_node *phandle_cache[OF_PHANDLE_CACHE_SZ]; -/* - * Caller must hold devtree_lock. - */ -static void __of_free_phandle_cache(void) +static u32 of_phandle_cache_hash(phandle handle) { - u32 cache_entries = phandle_cache_mask + 1; - u32 k; - - if (!phandle_cache) - return; - - for (k = 0; k < cache_entries; k++) - of_node_put(phandle_cache[k]); - - kfree(phandle_cache); - phandle_cache = NULL; -} - -int of_free_phandle_cache(void) -{ - unsigned long flags; - - raw_spin_lock_irqsave(&devtree_lock, flags); - - __of_free_phandle_cache(); - - raw_spin_unlock_irqrestore(&devtree_lock, flags); - - return 0; + return hash_32(handle, OF_PHANDLE_CACHE_BITS); } -#if !defined(CONFIG_MODULES) -late_initcall_sync(of_free_phandle_cache); -#endif /* * Caller must hold devtree_lock. */ -void __of_free_phandle_cache_entry(phandle handle) +void __of_phandle_cache_inv_entry(phandle handle) { - phandle masked_handle; + u32 handle_hash; struct device_node *np; if (!handle) return; - masked_handle = handle & phandle_cache_mask; + handle_hash = of_phandle_cache_hash(handle); - if (phandle_cache) { - np = phandle_cache[masked_handle]; - if (np && handle == np->phandle) { - of_node_put(np); - phandle_cache[masked_handle] = NULL; - } - } -} - -void of_populate_phandle_cache(void) -{ - unsigned long flags; - u32 cache_entries; - struct device_node *np; - u32 phandles = 0; - - raw_spin_lock_irqsave(&devtree_lock, flags); - - __of_free_phandle_cache(); - - for_each_of_allnodes(np) - if (np->phandle && np->phandle != OF_PHANDLE_ILLEGAL) - phandles++; - - if (!phandles) - goto out; - - cache_entries = roundup_pow_of_two(phandles); - phandle_cache_mask = cache_entries - 1; - - phandle_cache = kcalloc(cache_entries, sizeof(*phandle_cache), - GFP_ATOMIC); - if (!phandle_cache) - goto out; - - for_each_of_allnodes(np) - if (np->phandle && np->phandle != OF_PHANDLE_ILLEGAL) { - of_node_get(np); - phandle_cache[np->phandle & phandle_cache_mask] = np; - } - -out: - raw_spin_unlock_irqrestore(&devtree_lock, flags); + np = phandle_cache[handle_hash]; + if (np && handle == np->phandle) + phandle_cache[handle_hash] = NULL; } void __init of_core_init(void) { struct device_node *np; - of_populate_phandle_cache(); /* Create the kset, and register existing nodes */ mutex_lock(&of_mutex); @@ -253,8 +176,11 @@ void __init of_core_init(void) pr_err("failed to register existing nodes\n"); return; } - for_each_of_allnodes(np) + for_each_of_allnodes(np) { __of_attach_node_sysfs(np); + if (np->phandle && !phandle_cache[of_phandle_cache_hash(np->phandle)]) + phandle_cache[of_phandle_cache_hash(np->phandle)] = np; + } mutex_unlock(&of_mutex); /* Symlink in /proc as required by userspace ABI */ @@ -490,6 +416,42 @@ int of_cpu_node_to_id(struct device_node *cpu_node) EXPORT_SYMBOL(of_cpu_node_to_id); /** + * of_get_cpu_state_node - Get CPU's idle state node at the given index + * + * @cpu_node: The device node for the CPU + * @index: The index in the list of the idle states + * + * Two generic methods can be used to describe a CPU's idle states, either via + * a flattened description through the "cpu-idle-states" binding or via the + * hierarchical layout, using the "power-domains" and the "domain-idle-states" + * bindings. This function check for both and returns the idle state node for + * the requested index. + * + * In case an idle state node is found at @index, the refcount is incremented + * for it, so call of_node_put() on it when done. Returns NULL if not found. + */ +struct device_node *of_get_cpu_state_node(struct device_node *cpu_node, + int index) +{ + struct of_phandle_args args; + int err; + + err = of_parse_phandle_with_args(cpu_node, "power-domains", + "#power-domain-cells", 0, &args); + if (!err) { + struct device_node *state_node = + of_parse_phandle(args.np, "domain-idle-states", index); + + of_node_put(args.np); + if (state_node) + return state_node; + } + + return of_parse_phandle(cpu_node, "cpu-idle-states", index); +} +EXPORT_SYMBOL(of_get_cpu_state_node); + +/** * __of_device_is_compatible() - Check if the node matches given constraints * @device: pointer to node * @compat: required compatible string, NULL or "" for any match @@ -1235,36 +1197,24 @@ struct device_node *of_find_node_by_phandle(phandle handle) { struct device_node *np = NULL; unsigned long flags; - phandle masked_handle; + u32 handle_hash; if (!handle) return NULL; + handle_hash = of_phandle_cache_hash(handle); + raw_spin_lock_irqsave(&devtree_lock, flags); - masked_handle = handle & phandle_cache_mask; - - if (phandle_cache) { - if (phandle_cache[masked_handle] && - handle == phandle_cache[masked_handle]->phandle) - np = phandle_cache[masked_handle]; - if (np && of_node_check_flag(np, OF_DETACHED)) { - WARN_ON(1); /* did not uncache np on node removal */ - of_node_put(np); - phandle_cache[masked_handle] = NULL; - np = NULL; - } - } + if (phandle_cache[handle_hash] && + handle == phandle_cache[handle_hash]->phandle) + np = phandle_cache[handle_hash]; if (!np) { for_each_of_allnodes(np) if (np->phandle == handle && !of_node_check_flag(np, OF_DETACHED)) { - if (phandle_cache) { - /* will put when removed from cache */ - of_node_get(np); - phandle_cache[masked_handle] = np; - } + phandle_cache[handle_hash] = np; break; } } |