diff options
| -rw-r--r-- | arch/powerpc/include/asm/prom.h | 3 | ||||
| -rw-r--r-- | arch/powerpc/kernel/prom.c | 43 | ||||
| -rw-r--r-- | drivers/of/base.c | 95 | ||||
| -rw-r--r-- | include/linux/cpu.h | 1 | ||||
| -rw-r--r-- | include/linux/of.h | 7 |
5 files changed, 105 insertions, 44 deletions
diff --git a/arch/powerpc/include/asm/prom.h b/arch/powerpc/include/asm/prom.h index bc2da154f68b..ac204e022922 100644 --- a/arch/powerpc/include/asm/prom.h +++ b/arch/powerpc/include/asm/prom.h @@ -43,9 +43,6 @@ void of_parse_dma_window(struct device_node *dn, const void *dma_window_prop, extern void kdump_move_device_tree(void); -/* CPU OF node matching */ -struct device_node *of_get_cpu_node(int cpu, unsigned int *thread); - /* cache lookup */ struct device_node *of_find_next_cache_node(struct device_node *np); diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index 8b6f7a99cce2..00610a34fb9a 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -827,49 +827,10 @@ static int __init prom_reconfig_setup(void) __initcall(prom_reconfig_setup); #endif -/* Find the device node for a given logical cpu number, also returns the cpu - * local thread number (index in ibm,interrupt-server#s) if relevant and - * asked for (non NULL) - */ -struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) +bool arch_match_cpu_phys_id(int cpu, u64 phys_id) { - int hardid; - struct device_node *np; - - hardid = get_hard_smp_processor_id(cpu); - - for_each_node_by_type(np, "cpu") { - const u32 *intserv; - unsigned int plen, t; - - /* Check for ibm,ppc-interrupt-server#s. If it doesn't exist - * fallback to "reg" property and assume no threads - */ - intserv = of_get_property(np, "ibm,ppc-interrupt-server#s", - &plen); - if (intserv == NULL) { - const u32 *reg = of_get_property(np, "reg", NULL); - if (reg == NULL) - continue; - if (*reg == hardid) { - if (thread) - *thread = 0; - return np; - } - } else { - plen /= sizeof(u32); - for (t = 0; t < plen; t++) { - if (hardid == intserv[t]) { - if (thread) - *thread = t; - return np; - } - } - } - } - return NULL; + return (int)phys_id == get_hard_smp_processor_id(cpu); } -EXPORT_SYMBOL(of_get_cpu_node); #if defined(CONFIG_DEBUG_FS) && defined(DEBUG) static struct debugfs_blob_wrapper flat_dt_blob; diff --git a/drivers/of/base.c b/drivers/of/base.c index a6f584a7f4a1..9b6cd2d0e34f 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -18,6 +18,7 @@ * 2 of the License, or (at your option) any later version. */ #include <linux/ctype.h> +#include <linux/cpu.h> #include <linux/module.h> #include <linux/of.h> #include <linux/spinlock.h> @@ -230,6 +231,100 @@ 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 + * + * CPU logical to physical index mapping is architecture specific. + * However this __weak function provides a default match of physical + * id to logical cpu index. phys_id provided here is usually values read + * from the device tree which must match the hardware internal registers. + * + * Returns true if the physical identifier and the logical cpu index + * correspond to the same core/thread, false otherwise. + */ +bool __weak 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) + return false; + prop_len /= sizeof(*cell); + 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; +} + +/** + * 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 if found, else NULL. + */ +struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) +{ + struct device_node *cpun, *cpus; + + cpus = of_find_node_by_path("/cpus"); + if (!cpus) { + pr_warn("Missing cpus node, bailing out\n"); + return NULL; + } + + for_each_child_of_node(cpus, cpun) { + if (of_node_cmp(cpun->type, "cpu")) + continue; + /* Check for non-standard "ibm,ppc-interrupt-server#s" property + * for thread ids on PowerPC. If it doesn't exist fallback to + * standard "reg" property. + */ + if (IS_ENABLED(CONFIG_PPC) && + __of_find_n_match_cpu_property(cpun, + "ibm,ppc-interrupt-server#s", cpu, thread)) + return cpun; + if (__of_find_n_match_cpu_property(cpun, "reg", 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/linux/cpu.h b/include/linux/cpu.h index 9f3c7e81270a..322e0afc8634 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -29,6 +29,7 @@ struct cpu { extern int register_cpu(struct cpu *cpu, int num); extern struct device *get_cpu_device(unsigned cpu); extern bool cpu_is_hotpluggable(unsigned cpu); +extern bool arch_match_cpu_phys_id(int cpu, u64 phys_id); extern int cpu_add_dev_attr(struct device_attribute *attr); extern void cpu_remove_dev_attr(struct device_attribute *attr); diff --git a/include/linux/of.h b/include/linux/of.h index 1fd08ca23106..c0bb2f188048 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -266,6 +266,7 @@ extern int of_device_is_available(const struct device_node *device); extern const void *of_get_property(const struct device_node *node, const char *name, int *lenp); +extern struct device_node *of_get_cpu_node(int cpu, unsigned int *thread); #define for_each_property_of_node(dn, pp) \ for (pp = dn->properties; pp != NULL; pp = pp->next) @@ -459,6 +460,12 @@ static inline const void *of_get_property(const struct device_node *node, return NULL; } +static inline struct device_node *of_get_cpu_node(int cpu, + unsigned int *thread) +{ + return NULL; +} + static inline int of_property_read_u64(const struct device_node *np, const char *propname, u64 *out_value) { |