Signed-off-by: Antony Pavlov <antonynpavlov@xxxxxxxxx> --- drivers/of/base.c | 86 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ include/of.h | 10 +++++++ 2 files changed, 96 insertions(+) diff --git a/drivers/of/base.c b/drivers/of/base.c index 3099c91..1e6c33d 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -380,6 +380,92 @@ const void *of_get_property(const struct device_node *np, const char *name, } EXPORT_SYMBOL(of_get_property); +/* + * arch_match_cpu_phys_id - Match the given logical CPU and physical id + * + * @cpu: logical cpu index of a core/thread + * @phys_id: physical identifier of a core/thread + * + * Returns true if the physical identifier and the logical cpu index + * correspond to the same core/thread, false otherwise. + */ +static bool arch_match_cpu_phys_id(int cpu, u64 phys_id) +{ + return (u32)phys_id == cpu; +} + +/** + * Checks if the given "prop_name" property holds the physical id of the + * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not + * NULL, local thread number within the core is returned in it. + */ +static bool __of_find_n_match_cpu_property(struct device_node *cpun, + const char *prop_name, int cpu, unsigned int *thread) +{ + const __be32 *cell; + int ac, prop_len, tid; + u64 hwid; + + ac = of_n_addr_cells(cpun); + cell = of_get_property(cpun, prop_name, &prop_len); + if (!cell || !ac) + return false; + prop_len /= sizeof(*cell) * ac; + for (tid = 0; tid < prop_len; tid++) { + hwid = of_read_number(cell, ac); + if (arch_match_cpu_phys_id(cpu, hwid)) { + if (thread) + *thread = tid; + return true; + } + cell += ac; + } + return false; +} + +/* + * arch_find_n_match_cpu_physical_id - See if the given device node is + * for the cpu corresponding to logical cpu 'cpu'. Return true if so, + * else false. If 'thread' is non-NULL, the local thread number within the + * core is returned in it. + */ +static bool arch_find_n_match_cpu_physical_id(struct device_node *cpun, + int cpu, unsigned int *thread) +{ + return __of_find_n_match_cpu_property(cpun, "reg", cpu, thread); +} + +/** + * of_get_cpu_node - Get device node associated with the given logical CPU + * + * @cpu: CPU number(logical index) for which device node is required + * @thread: if not NULL, local thread number within the physical core is + * returned + * + * The main purpose of this function is to retrieve the device node for the + * given logical CPU index. It should be used to initialize the of_node in + * cpu device. Once of_node in cpu device is populated, all the further + * references can use that instead. + * + * CPU logical to physical index mapping is architecture specific and is built + * before booting secondary cores. This function uses arch_match_cpu_phys_id + * which can be overridden by architecture specific implementation. + * + * Returns a node pointer for the logical cpu with refcount incremented, use + * of_node_put() on it when done. Returns NULL if not found. + */ +struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) +{ + struct device_node *cpun; + + for_each_node_by_type(cpun, "cpu") { + if (arch_find_n_match_cpu_physical_id(cpun, cpu, thread)) + return cpun; + } + return NULL; +} +EXPORT_SYMBOL(of_get_cpu_node); + /** Checks if the given "compat" string matches one of the strings in * the device's "compatible" property */ diff --git a/include/of.h b/include/of.h index 8c8f57a..ed6e870 100644 --- a/include/of.h +++ b/include/of.h @@ -111,6 +111,7 @@ extern struct property *of_find_property(const struct device_node *np, const char *name, int *lenp); extern const void *of_get_property(const struct device_node *np, const char *name, int *lenp); +extern struct device_node *of_get_cpu_node(int cpu, unsigned int *thread); extern int of_set_property(struct device_node *node, const char *p, const void *val, int len, int create); @@ -347,6 +348,12 @@ static inline const void *of_get_property(const struct device_node *np, return NULL; } +static inline struct device_node *of_get_cpu_node(int cpu, + unsigned int *thread) +{ + return NULL; +} + static inline int of_set_property(struct device_node *node, const char *p, const void *val, int len, int create) { @@ -639,6 +646,9 @@ static inline struct device_node *of_find_node_by_path_or_alias( #define for_each_node_by_name(dn, name) \ for (dn = of_find_node_by_name(NULL, name); dn; \ dn = of_find_node_by_name(dn, name)) +#define for_each_node_by_type(dn, type) \ + for (dn = of_find_node_by_type(NULL, type); dn; \ + dn = of_find_node_by_type(dn, type)) #define for_each_node_by_name_from(dn, root, name) \ for (dn = of_find_node_by_name(root, name); dn; \ dn = of_find_node_by_name(dn, name)) -- 2.8.1 _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox