From: David Miller Date: Thu, 3 Oct 2013 21:24:51 +0000 (-0400) Subject: of: Make cpu node handling more portable. X-Git-Tag: firefly_0821_release~176^2~5004^2~4^2~17 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d1cb9d1af0bc11b7450a6032f43935c746609418;p=firefly-linux-kernel-4.4.55.git of: Make cpu node handling more portable. Use for_each_node_by_type() to iterate all cpu nodes in the system. Provide and overridable function arch_find_n_match_cpu_physical_id, which sees if the given device node matches 'cpu' and if so sets '*thread' when non-NULL to the cpu thread number within the core. The default implementation behaves the same as the existing code. Add a sparc64 implementation. Signed-off-by: David S. Miller Tested-by: Sudeep KarkadaNagesha Signed-off-by: Grant Likely --- diff --git a/arch/sparc/kernel/prom_64.c b/arch/sparc/kernel/prom_64.c index d397d7fc5c28..6b39125eb927 100644 --- a/arch/sparc/kernel/prom_64.c +++ b/arch/sparc/kernel/prom_64.c @@ -373,6 +373,59 @@ static const char *get_mid_prop(void) return (tlb_type == spitfire ? "upa-portid" : "portid"); } +bool arch_find_n_match_cpu_physical_id(struct device_node *cpun, + int cpu, unsigned int *thread) +{ + const char *mid_prop = get_mid_prop(); + int this_cpu_id; + + /* On hypervisor based platforms we interrogate the 'reg' + * property. On everything else we look for a 'upa-portis', + * 'portid', or 'cpuid' property. + */ + + if (tlb_type == hypervisor) { + struct property *prop = of_find_property(cpun, "reg", NULL); + u32 *regs; + + if (!prop) { + pr_warn("CPU node missing reg property\n"); + return false; + } + regs = prop->value; + this_cpu_id = regs[0] & 0x0fffffff; + } else { + this_cpu_id = of_getintprop_default(cpun, mid_prop, -1); + + if (this_cpu_id < 0) { + mid_prop = "cpuid"; + this_cpu_id = of_getintprop_default(cpun, mid_prop, -1); + } + if (this_cpu_id < 0) { + pr_warn("CPU node missing cpu ID property\n"); + return false; + } + } + if (this_cpu_id == cpu) { + if (thread) { + int proc_id = cpu_data(cpu).proc_id; + + /* On sparc64, the cpu thread information is obtained + * either from OBP or the machine description. We've + * actually probed this information already long before + * this interface gets called so instead of interrogating + * both the OF node and the MDESC again, just use what + * we discovered already. + */ + if (proc_id < 0) + proc_id = 0; + *thread = proc_id; + } + return true; + } + return false; +} + static void *of_iterate_over_cpus(void *(*func)(struct device_node *, int, int), int arg) { struct device_node *dp; diff --git a/drivers/of/base.c b/drivers/of/base.c index 7d4c70f859e3..e4c99453adf1 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -280,6 +280,31 @@ static bool __of_find_n_match_cpu_property(struct device_node *cpun, 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. + */ +bool __weak arch_find_n_match_cpu_physical_id(struct device_node *cpun, + int cpu, unsigned int *thread) +{ + /* 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 true; + + if (__of_find_n_match_cpu_property(cpun, "reg", cpu, thread)) + return true; + + return false; +} + /** * of_get_cpu_node - Get device node associated with the given logical CPU * @@ -300,24 +325,10 @@ static bool __of_find_n_match_cpu_property(struct device_node *cpun, */ 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) - return NULL; + struct device_node *cpun; - 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)) + for_each_node_by_type(cpun, "cpu") { + if (arch_find_n_match_cpu_physical_id(cpun, cpu, thread)) return cpun; } return NULL; diff --git a/include/linux/cpu.h b/include/linux/cpu.h index 801ff9e73679..fbd25c3c2923 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -18,6 +18,7 @@ #include struct device; +struct device_node; struct cpu { int node_id; /* The node which contains the CPU */ @@ -29,6 +30,8 @@ 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 bool arch_find_n_match_cpu_physical_id(struct device_node *cpun, + int cpu, unsigned int *thread); extern int cpu_add_dev_attr(struct device_attribute *attr); extern void cpu_remove_dev_attr(struct device_attribute *attr);