From dca463daa0151c5bbbd8ec8fd42882a3966d3c44 Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Thu, 15 Nov 2012 17:30:32 +0000 Subject: ARM: kernel: enhance MPIDR macro definitions Kernel subsystems other than the topology layer need the MPIDR mask definitions to access the MPIDR without relying on hardcoded masks. This patch moves the MPIDR register masks definition to a header file and defines a macro to simplify access to MPIDR bit fields representing affinity levels. Signed-off-by: Lorenzo Pieralisi Acked-by: Will Deacon Acked-by: Nicolas Pitre --- arch/arm/include/asm/cputype.h | 13 +++++++++++++ arch/arm/kernel/topology.c | 27 +-------------------------- 2 files changed, 14 insertions(+), 26 deletions(-) (limited to 'arch') diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h index cb47d28cbe1f..a59dcb5ab5fc 100644 --- a/arch/arm/include/asm/cputype.h +++ b/arch/arm/include/asm/cputype.h @@ -25,6 +25,19 @@ #define CPUID_EXT_ISAR4 "c2, 4" #define CPUID_EXT_ISAR5 "c2, 5" +#define MPIDR_SMP_BITMASK (0x3 << 30) +#define MPIDR_SMP_VALUE (0x2 << 30) + +#define MPIDR_MT_BITMASK (0x1 << 24) + +#define MPIDR_HWID_BITMASK 0xFFFFFF + +#define MPIDR_LEVEL_BITS 8 +#define MPIDR_LEVEL_MASK ((1 << MPIDR_LEVEL_BITS) - 1) + +#define MPIDR_AFFINITY_LEVEL(mpidr, level) \ + ((mpidr >> (MPIDR_LEVEL_BITS * level)) & MPIDR_LEVEL_MASK) + extern unsigned int processor_id; #ifdef CONFIG_CPU_CP15 diff --git a/arch/arm/kernel/topology.c b/arch/arm/kernel/topology.c index 26c12c6440fc..cd68d1aa9c3d 100644 --- a/arch/arm/kernel/topology.c +++ b/arch/arm/kernel/topology.c @@ -196,32 +196,7 @@ static inline void parse_dt_topology(void) {} static inline void update_cpu_power(unsigned int cpuid, unsigned int mpidr) {} #endif - -/* - * cpu topology management - */ - -#define MPIDR_SMP_BITMASK (0x3 << 30) -#define MPIDR_SMP_VALUE (0x2 << 30) - -#define MPIDR_MT_BITMASK (0x1 << 24) - -/* - * These masks reflect the current use of the affinity levels. - * The affinity level can be up to 16 bits according to ARM ARM - */ -#define MPIDR_HWID_BITMASK 0xFFFFFF - -#define MPIDR_LEVEL0_MASK 0x3 -#define MPIDR_LEVEL0_SHIFT 0 - -#define MPIDR_LEVEL1_MASK 0xF -#define MPIDR_LEVEL1_SHIFT 8 - -#define MPIDR_LEVEL2_MASK 0xFF -#define MPIDR_LEVEL2_SHIFT 16 - -/* + /* * cpu topology table */ struct cputopo_arm cpu_topology[NR_CPUS]; -- cgit v1.2.3 From 71db5bfec1349afcbfbd71268c01c658c357b4f3 Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Fri, 16 Nov 2012 15:24:06 +0000 Subject: ARM: kernel: update topology to use new MPIDR macros This patch updates the topology initialization code to use the newly defined accessors to retrieve the MPIDR affinity levels. Signed-off-by: Lorenzo Pieralisi Acked-by: Will Deacon Acked-by: Nicolas Pitre --- arch/arm/kernel/topology.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) (limited to 'arch') diff --git a/arch/arm/kernel/topology.c b/arch/arm/kernel/topology.c index cd68d1aa9c3d..79282ebcd939 100644 --- a/arch/arm/kernel/topology.c +++ b/arch/arm/kernel/topology.c @@ -257,19 +257,14 @@ void store_cpu_topology(unsigned int cpuid) if (mpidr & MPIDR_MT_BITMASK) { /* core performance interdependency */ - cpuid_topo->thread_id = (mpidr >> MPIDR_LEVEL0_SHIFT) - & MPIDR_LEVEL0_MASK; - cpuid_topo->core_id = (mpidr >> MPIDR_LEVEL1_SHIFT) - & MPIDR_LEVEL1_MASK; - cpuid_topo->socket_id = (mpidr >> MPIDR_LEVEL2_SHIFT) - & MPIDR_LEVEL2_MASK; + cpuid_topo->thread_id = MPIDR_AFFINITY_LEVEL(mpidr, 0); + cpuid_topo->core_id = MPIDR_AFFINITY_LEVEL(mpidr, 1); + cpuid_topo->socket_id = MPIDR_AFFINITY_LEVEL(mpidr, 2); } else { /* largely independent cores */ cpuid_topo->thread_id = -1; - cpuid_topo->core_id = (mpidr >> MPIDR_LEVEL0_SHIFT) - & MPIDR_LEVEL0_MASK; - cpuid_topo->socket_id = (mpidr >> MPIDR_LEVEL1_SHIFT) - & MPIDR_LEVEL1_MASK; + cpuid_topo->core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0); + cpuid_topo->socket_id = MPIDR_AFFINITY_LEVEL(mpidr, 1); } } else { /* -- cgit v1.2.3 From cb8cf4f821044f140ea5b9c8d4f816f0c05fab44 Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Thu, 8 Nov 2012 18:05:56 +0000 Subject: ARM: kernel: smp_setup_processor_id() updates This patch applies some basic changes to the smp_setup_processor_id() ARM implementation to make the code that builds cpu_logical_map more uniform across the kernel. The function now prints the full extent of the boot CPU MPIDR[23:0] and initializes the cpu_logical_map for CPUs up to nr_cpu_ids. Signed-off-by: Lorenzo Pieralisi Acked-by: Nicolas Pitre Acked-by: Will Deacon --- arch/arm/kernel/setup.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'arch') diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index da1d1aa20ad9..4515bf6abee0 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -426,13 +426,14 @@ int __cpu_logical_map[NR_CPUS]; void __init smp_setup_processor_id(void) { int i; - u32 cpu = is_smp() ? read_cpuid_mpidr() & 0xff : 0; + u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0; + u32 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); cpu_logical_map(0) = cpu; - for (i = 1; i < NR_CPUS; ++i) + for (i = 1; i < nr_cpu_ids; ++i) cpu_logical_map(i) = i == cpu ? 0 : i; - printk(KERN_INFO "Booting Linux on physical CPU %d\n", cpu); + printk(KERN_INFO "Booting Linux on physical CPU 0x%x\n", mpidr); } static void __init setup_processor(void) -- cgit v1.2.3 From a0ae02405076ac32bd17ece976e914b5b6075bb0 Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Thu, 17 Nov 2011 17:31:51 +0000 Subject: ARM: kernel: add device tree init map function When booting through a device tree, the kernel cpu logical id map can be initialized using device tree data passed by FW or through an embedded blob. This patch adds a function that parses device tree "cpu" nodes and retrieves the corresponding CPUs hardware identifiers (MPIDR). It sets the possible cpus and the cpu logical map values according to the number of CPUs defined in the device tree and respective properties. The device tree HW identifiers are considered valid if all CPU nodes contain a "reg" property, there are no duplicate "reg" entries and the DT defines a CPU node whose "reg" property matches the MPIDR[23:0] of the boot CPU. The primary CPU is assigned cpu logical number 0 to keep the current convention valid. Current bindings documentation is included in the patch: Documentation/devicetree/bindings/arm/cpus.txt Signed-off-by: Lorenzo Pieralisi Acked-by: Nicolas Pitre --- arch/arm/include/asm/prom.h | 2 + arch/arm/kernel/devtree.c | 100 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 102 insertions(+) (limited to 'arch') diff --git a/arch/arm/include/asm/prom.h b/arch/arm/include/asm/prom.h index aeae9c609df4..8dd51dc1a367 100644 --- a/arch/arm/include/asm/prom.h +++ b/arch/arm/include/asm/prom.h @@ -15,6 +15,7 @@ extern struct machine_desc *setup_machine_fdt(unsigned int dt_phys); extern void arm_dt_memblock_reserve(void); +extern void __init arm_dt_init_cpu_maps(void); #else /* CONFIG_OF */ @@ -24,6 +25,7 @@ static inline struct machine_desc *setup_machine_fdt(unsigned int dt_phys) } static inline void arm_dt_memblock_reserve(void) { } +static inline void arm_dt_init_cpu_maps(void) { } #endif /* CONFIG_OF */ #endif /* ASMARM_PROM_H */ diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c index bee7f9d47f02..aaf9add497fe 100644 --- a/arch/arm/kernel/devtree.c +++ b/arch/arm/kernel/devtree.c @@ -19,8 +19,10 @@ #include #include +#include #include #include +#include #include #include @@ -61,6 +63,104 @@ void __init arm_dt_memblock_reserve(void) } } +/* + * arm_dt_init_cpu_maps - Function retrieves cpu nodes from the device tree + * and builds the cpu logical map array containing MPIDR values related to + * logical cpus + * + * Updates the cpu possible mask with the number of parsed cpu nodes + */ +void __init arm_dt_init_cpu_maps(void) +{ + /* + * Temp logical map is initialized with UINT_MAX values that are + * considered invalid logical map entries since the logical map must + * contain a list of MPIDR[23:0] values where MPIDR[31:24] must + * read as 0. + */ + struct device_node *cpu, *cpus; + u32 i, j, cpuidx = 1; + u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0; + + u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = UINT_MAX }; + bool bootcpu_valid = false; + cpus = of_find_node_by_path("/cpus"); + + if (!cpus) + return; + + for_each_child_of_node(cpus, cpu) { + u32 hwid; + + pr_debug(" * %s...\n", cpu->full_name); + /* + * A device tree containing CPU nodes with missing "reg" + * properties is considered invalid to build the + * cpu_logical_map. + */ + if (of_property_read_u32(cpu, "reg", &hwid)) { + pr_debug(" * %s missing reg property\n", + cpu->full_name); + return; + } + + /* + * 8 MSBs must be set to 0 in the DT since the reg property + * defines the MPIDR[23:0]. + */ + if (hwid & ~MPIDR_HWID_BITMASK) + return; + + /* + * Duplicate MPIDRs are a recipe for disaster. + * Scan all initialized entries and check for + * duplicates. If any is found just bail out. + * temp values were initialized to UINT_MAX + * to avoid matching valid MPIDR[23:0] values. + */ + for (j = 0; j < cpuidx; j++) + if (WARN(tmp_map[j] == hwid, "Duplicate /cpu reg " + "properties in the DT\n")) + return; + + /* + * Build a stashed array of MPIDR values. Numbering scheme + * requires that if detected the boot CPU must be assigned + * logical id 0. Other CPUs get sequential indexes starting + * from 1. If a CPU node with a reg property matching the + * boot CPU MPIDR is detected, this is recorded so that the + * logical map built from DT is validated and can be used + * to override the map created in smp_setup_processor_id(). + */ + if (hwid == mpidr) { + i = 0; + bootcpu_valid = true; + } else { + i = cpuidx++; + } + + tmp_map[i] = hwid; + + if (cpuidx > nr_cpu_ids) + break; + } + + if (WARN(!bootcpu_valid, "DT missing boot CPU MPIDR[23:0], " + "fall back to default cpu_logical_map\n")) + return; + + /* + * Since the boot CPU node contains proper data, and all nodes have + * a reg property, the DT CPU list can be considered valid and the + * logical map created in smp_setup_processor_id() can be overridden + */ + for (i = 0; i < cpuidx; i++) { + set_cpu_possible(i, true); + cpu_logical_map(i) = tmp_map[i]; + pr_debug("cpu logical map 0x%x\n", cpu_logical_map(i)); + } +} + /** * setup_machine_fdt - Machine setup when an dtb was passed to the kernel * @dt_phys: physical address of dt blob -- cgit v1.2.3 From 5587164eea4aad88fcb79d9b21dc8f14fea598cd Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Wed, 14 Dec 2011 16:01:24 +0000 Subject: ARM: kernel: add cpu logical map DT init in setup_arch As soon as the device tree is unflattened the cpu logical to physical mapping is carried out in setup_arch to build a proper array of MPIDR and corresponding logical indexes. The mapping could have been carried out using the flattened DT blob and related primitives, but since the mapping is not needed by early boot code it can safely be executed when the device tree has been uncompressed to its tree data structure. This patch adds the arm_dt_init_cpu maps() function call in setup_arch(). If the kernel is not compiled with DT support the function is empty and no logical mapping takes place through it; the mapping carried out in smp_setup_processor_id() is left unchanged. If DT is supported the mapping created in smp_setup_processor_id() is overriden. The DT mapping also sets the possible cpus mask, hence platform code need not set it again in the respective smp_init_cpus() functions. Signed-off-by: Lorenzo Pieralisi Acked-by: Will Deacon Acked-by: Nicolas Pitre --- arch/arm/kernel/setup.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch') diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 4515bf6abee0..d15f1c503f3d 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -759,6 +759,7 @@ void __init setup_arch(char **cmdline_p) unflatten_device_tree(); + arm_dt_init_cpu_maps(); #ifdef CONFIG_SMP if (is_smp()) { smp_set_ops(mdesc->smp); -- cgit v1.2.3 From 7f124aaf01439d2fa54283f3c375ce3b9fc776d4 Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Thu, 17 Nov 2011 17:36:24 +0000 Subject: ARM: kernel: add logical mappings look-up In ARM SMP systems the MPIDR register ([23:0] bits) is used to uniquely identify CPUs. In order to retrieve the logical CPU index corresponding to a given MPIDR value and guarantee a consistent translation throughout the kernel, this patch adds a look-up based on the MPIDR[23:0] so that kernel subsystems can use it whenever the logical cpu index corresponding to a given MPIDR value is needed. Signed-off-by: Lorenzo Pieralisi Acked-by: Will Deacon Acked-by: Nicolas Pitre --- arch/arm/include/asm/smp_plat.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'arch') diff --git a/arch/arm/include/asm/smp_plat.h b/arch/arm/include/asm/smp_plat.h index 558d6c80aca9..aaa61b6f50ff 100644 --- a/arch/arm/include/asm/smp_plat.h +++ b/arch/arm/include/asm/smp_plat.h @@ -5,6 +5,9 @@ #ifndef __ASMARM_SMP_PLAT_H #define __ASMARM_SMP_PLAT_H +#include +#include + #include /* @@ -48,5 +51,19 @@ static inline int cache_ops_need_broadcast(void) */ extern int __cpu_logical_map[]; #define cpu_logical_map(cpu) __cpu_logical_map[cpu] +/* + * Retrieve logical cpu index corresponding to a given MPIDR[23:0] + * - mpidr: MPIDR[23:0] to be used for the look-up + * + * Returns the cpu logical index or -EINVAL on look-up error + */ +static inline int get_logical_index(u32 mpidr) +{ + int cpu; + for (cpu = 0; cpu < nr_cpu_ids; cpu++) + if (cpu_logical_map(cpu) == mpidr) + return cpu; + return -EINVAL; +} #endif -- cgit v1.2.3 From 384a290283fde63ba8dc671fca5420111cdac19a Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Wed, 11 Apr 2012 18:55:48 -0400 Subject: ARM: gic: use a private mapping for CPU target interfaces The GIC interface numbering does not necessarily follow the logical CPU numbering, especially for complex topologies such as multi-cluster systems. Fortunately we can easily probe the GIC to create a mapping as the Interrupt Processor Targets Registers for the first 32 interrupts are read-only, and each field returns a value that always corresponds to the processor reading the register. Initially all mappings target all CPUs in case an IPI is required to boot secondary CPUs. It is refined as those CPUs discover what their actual mapping is. Signed-off-by: Nicolas Pitre Acked-by: Will Deacon --- arch/arm/common/gic.c | 45 ++++++++++++++++++++++++++++++++++++--------- 1 file changed, 36 insertions(+), 9 deletions(-) (limited to 'arch') diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c index aa5269984187..36ae03a3f5d1 100644 --- a/arch/arm/common/gic.c +++ b/arch/arm/common/gic.c @@ -69,6 +69,14 @@ struct gic_chip_data { static DEFINE_RAW_SPINLOCK(irq_controller_lock); +/* + * The GIC mapping of CPU interfaces does not necessarily match + * the logical CPU numbering. Let's use a mapping as returned + * by the GIC itself. + */ +#define NR_GIC_CPU_IF 8 +static u8 gic_cpu_map[NR_GIC_CPU_IF] __read_mostly; + /* * Supported arch specific GIC irq extension. * Default make them NULL. @@ -238,11 +246,11 @@ static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val, unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask); u32 val, mask, bit; - if (cpu >= 8 || cpu >= nr_cpu_ids) + if (cpu >= NR_GIC_CPU_IF || cpu >= nr_cpu_ids) return -EINVAL; mask = 0xff << shift; - bit = 1 << (cpu_logical_map(cpu) + shift); + bit = gic_cpu_map[cpu] << shift; raw_spin_lock(&irq_controller_lock); val = readl_relaxed(reg) & ~mask; @@ -349,11 +357,6 @@ static void __init gic_dist_init(struct gic_chip_data *gic) u32 cpumask; unsigned int gic_irqs = gic->gic_irqs; void __iomem *base = gic_data_dist_base(gic); - u32 cpu = cpu_logical_map(smp_processor_id()); - - cpumask = 1 << cpu; - cpumask |= cpumask << 8; - cpumask |= cpumask << 16; writel_relaxed(0, base + GIC_DIST_CTRL); @@ -366,6 +369,7 @@ static void __init gic_dist_init(struct gic_chip_data *gic) /* * Set all global interrupts to this CPU only. */ + cpumask = readl_relaxed(base + GIC_DIST_TARGET + 0); for (i = 32; i < gic_irqs; i += 4) writel_relaxed(cpumask, base + GIC_DIST_TARGET + i * 4 / 4); @@ -389,8 +393,24 @@ static void __cpuinit gic_cpu_init(struct gic_chip_data *gic) { void __iomem *dist_base = gic_data_dist_base(gic); void __iomem *base = gic_data_cpu_base(gic); + unsigned int cpu_mask, cpu = smp_processor_id(); int i; + /* + * Get what the GIC says our CPU mask is. + */ + BUG_ON(cpu >= NR_GIC_CPU_IF); + cpu_mask = readl_relaxed(dist_base + GIC_DIST_TARGET + 0); + gic_cpu_map[cpu] = cpu_mask; + + /* + * Clear our mask from the other map entries in case they're + * still undefined. + */ + for (i = 0; i < NR_GIC_CPU_IF; i++) + if (i != cpu) + gic_cpu_map[i] &= ~cpu_mask; + /* * Deal with the banked PPI and SGI interrupts - disable all * PPI interrupts, ensure all SGI interrupts are enabled. @@ -646,7 +666,7 @@ void __init gic_init_bases(unsigned int gic_nr, int irq_start, { irq_hw_number_t hwirq_base; struct gic_chip_data *gic; - int gic_irqs, irq_base; + int gic_irqs, irq_base, i; BUG_ON(gic_nr >= MAX_GIC_NR); @@ -682,6 +702,13 @@ void __init gic_init_bases(unsigned int gic_nr, int irq_start, gic_set_base_accessor(gic, gic_get_common_base); } + /* + * Initialize the CPU interface map to all CPUs. + * It will be refined as each CPU probes its ID. + */ + for (i = 0; i < NR_GIC_CPU_IF; i++) + gic_cpu_map[i] = 0xff; + /* * For primary GICs, skip over SGIs. * For secondary GICs, skip over PPIs, too. @@ -737,7 +764,7 @@ void gic_raise_softirq(const struct cpumask *mask, unsigned int irq) /* Convert our logical CPU mask into a physical one. */ for_each_cpu(cpu, mask) - map |= 1 << cpu_logical_map(cpu); + map |= gic_cpu_map[cpu]; /* * Ensure that stores to Normal memory are visible to the -- cgit v1.2.3