#include #include #include #include #include #include #if defined(__ANDROID__) #include #endif #include #include #include #include #include #include #define CLUSTERS_MAX 3 static inline bool bitmask_all(uint32_t bitfield, uint32_t mask) { return (bitfield & mask) == mask; } /* Description of core clusters configuration in a chipset (identified by series and model number) */ struct cluster_config { /* Number of cores (logical processors) */ uint8_t cores; /* ARM chipset series (see cpuinfo_arm_chipset_series enum) */ uint8_t series; /* Chipset model number (see cpuinfo_arm_chipset struct) */ uint16_t model; /* Number of heterogenous clusters in the CPU package */ uint8_t clusters; /* * Number of cores in each cluster: # - Symmetric configurations: [0] = # cores * - big.LITTLE configurations: [0] = # LITTLE cores, [1] = # big cores * - Max.Med.Min configurations: [0] = # Min cores, [1] = # Med cores, [2] = # Max cores */ uint8_t cluster_cores[CLUSTERS_MAX]; /* * MIDR of cores in each cluster: * - Symmetric configurations: [0] = core MIDR * - big.LITTLE configurations: [0] = LITTLE core MIDR, [1] = big core MIDR * - Max.Med.Min configurations: [0] = Min core MIDR, [1] = Med core MIDR, [2] = Max core MIDR */ uint32_t cluster_midr[CLUSTERS_MAX]; }; /* * The list of chipsets where MIDR may not be unambigiously decoded at least on some devices. * The typical reasons for impossibility to decoded MIDRs are buggy kernels, which either do not report all MIDR * information (e.g. on ATM7029 kernel doesn't report CPU Part), or chipsets have more than one type of cores * (i.e. 4x Cortex-A53 + 4x Cortex-A53 is out) and buggy kernels report MIDR information only about some cores * in /proc/cpuinfo (either only online cores, or only the core that reads /proc/cpuinfo). On these kernels/chipsets, * it is not possible to detect all core types by just parsing /proc/cpuinfo, so we use chipset name and this table to * find their MIDR (and thus microarchitecture, cache, etc). * * Note: not all chipsets with heterogeneous multiprocessing need an entry in this table. The following HMP * chipsets always list information about all cores in /proc/cpuinfo: * * - Snapdragon 660 * - Snapdragon 820 (MSM8996) * - Snapdragon 821 (MSM8996PRO) * - Snapdragon 835 (MSM8998) * - Exynos 8895 * - Kirin 960 * * As these are all new processors, there is hope that this table won't uncontrollably grow over time. */ static const struct cluster_config cluster_configs[] = { #if CPUINFO_ARCH_ARM { /* * MSM8916 (Snapdragon 410): 4x Cortex-A53 * Some AArch32 phones use non-standard /proc/cpuinfo format. */ .cores = 4, .series = cpuinfo_arm_chipset_series_qualcomm_msm, .model = UINT16_C(8916), .clusters = 1, .cluster_cores = { [0] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FD030), }, }, { /* * MSM8939 (Snapdragon 615): 4x Cortex-A53 + 4x Cortex-A53 * Some AArch32 phones use non-standard /proc/cpuinfo format. */ .cores = 8, .series = cpuinfo_arm_chipset_series_qualcomm_msm, .model = UINT16_C(8939), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FD034), [1] = UINT32_C(0x410FD034), }, }, #endif { /* MSM8956 (Snapdragon 650): 2x Cortex-A72 + 4x Cortex-A53 */ .cores = 6, .series = cpuinfo_arm_chipset_series_qualcomm_msm, .model = UINT16_C(8956), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 2, }, .cluster_midr = { [0] = UINT32_C(0x410FD034), [1] = UINT32_C(0x410FD080), }, }, { /* MSM8976/MSM8976PRO (Snapdragon 652/653): 4x Cortex-A72 + 4x Cortex-A53 */ .cores = 8, .series = cpuinfo_arm_chipset_series_qualcomm_msm, .model = UINT16_C(8976), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FD034), [1] = UINT32_C(0x410FD080), }, }, { /* MSM8992 (Snapdragon 808): 2x Cortex-A57 + 4x Cortex-A53 */ .cores = 6, .series = cpuinfo_arm_chipset_series_qualcomm_msm, .model = UINT16_C(8992), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 2, }, .cluster_midr = { [0] = UINT32_C(0x410FD033), [1] = UINT32_C(0x411FD072), }, }, { /* MSM8994/MSM8994V (Snapdragon 810): 4x Cortex-A57 + 4x Cortex-A53 */ .cores = 8, .series = cpuinfo_arm_chipset_series_qualcomm_msm, .model = UINT16_C(8994), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FD032), [1] = UINT32_C(0x411FD071), }, }, #if CPUINFO_ARCH_ARM { /* Exynos 5422: 4x Cortex-A15 + 4x Cortex-A7 */ .cores = 8, .series = cpuinfo_arm_chipset_series_samsung_exynos, .model = UINT16_C(5422), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FC073), [1] = UINT32_C(0x412FC0F3), }, }, { /* Exynos 5430: 4x Cortex-A15 + 4x Cortex-A7 */ .cores = 8, .series = cpuinfo_arm_chipset_series_samsung_exynos, .model = UINT16_C(5430), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FC074), [1] = UINT32_C(0x413FC0F3), }, }, #endif /* CPUINFO_ARCH_ARM */ { /* Exynos 5433: 4x Cortex-A57 + 4x Cortex-A53 */ .cores = 8, .series = cpuinfo_arm_chipset_series_samsung_exynos, .model = UINT16_C(5433), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FD031), [1] = UINT32_C(0x411FD070), }, }, { /* Exynos 7420: 4x Cortex-A57 + 4x Cortex-A53 */ .cores = 8, .series = cpuinfo_arm_chipset_series_samsung_exynos, .model = UINT16_C(7420), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FD032), [1] = UINT32_C(0x411FD070), }, }, { /* Exynos 8890: 4x Exynos M1 + 4x Cortex-A53 */ .cores = 8, .series = cpuinfo_arm_chipset_series_samsung_exynos, .model = UINT16_C(8890), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FD034), [1] = UINT32_C(0x531F0011), }, }, #if CPUINFO_ARCH_ARM { /* Kirin 920: 4x Cortex-A15 + 4x Cortex-A7 */ .cores = 8, .series = cpuinfo_arm_chipset_series_hisilicon_kirin, .model = UINT16_C(920), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FC075), [1] = UINT32_C(0x413FC0F3), }, }, { /* Kirin 925: 4x Cortex-A15 + 4x Cortex-A7 */ .cores = 8, .series = cpuinfo_arm_chipset_series_hisilicon_kirin, .model = UINT16_C(925), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FC075), [1] = UINT32_C(0x413FC0F3), }, }, { /* Kirin 928: 4x Cortex-A15 + 4x Cortex-A7 */ .cores = 8, .series = cpuinfo_arm_chipset_series_hisilicon_kirin, .model = UINT16_C(928), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FC075), [1] = UINT32_C(0x413FC0F3), }, }, #endif /* CPUINFO_ARCH_ARM */ { /* Kirin 950: 4x Cortex-A72 + 4x Cortex-A53 */ .cores = 8, .series = cpuinfo_arm_chipset_series_hisilicon_kirin, .model = UINT16_C(950), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FD034), [1] = UINT32_C(0x410FD080), }, }, { /* Kirin 955: 4x Cortex-A72 + 4x Cortex-A53 */ .cores = 8, .series = cpuinfo_arm_chipset_series_hisilicon_kirin, .model = UINT16_C(955), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FD034), [1] = UINT32_C(0x410FD080), }, }, #if CPUINFO_ARCH_ARM { /* MediaTek MT8135: 2x Cortex-A7 + 2x Cortex-A15 */ .cores = 4, .series = cpuinfo_arm_chipset_series_mediatek_mt, .model = UINT16_C(8135), .clusters = 2, .cluster_cores = { [0] = 2, [1] = 2, }, .cluster_midr = { [0] = UINT32_C(0x410FC073), [1] = UINT32_C(0x413FC0F2), }, }, #endif { /* MediaTek MT8173: 2x Cortex-A72 + 2x Cortex-A53 */ .cores = 4, .series = cpuinfo_arm_chipset_series_mediatek_mt, .model = UINT16_C(8173), .clusters = 2, .cluster_cores = { [0] = 2, [1] = 2, }, .cluster_midr = { [0] = UINT32_C(0x410FD032), [1] = UINT32_C(0x410FD080), }, }, { /* MediaTek MT8176: 2x Cortex-A72 + 4x Cortex-A53 */ .cores = 6, .series = cpuinfo_arm_chipset_series_mediatek_mt, .model = UINT16_C(8176), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 2, }, .cluster_midr = { [0] = UINT32_C(0x410FD032), [1] = UINT32_C(0x410FD080), }, }, #if CPUINFO_ARCH_ARM64 { /* * MediaTek MT8735: 4x Cortex-A53 * Some AArch64 phones use non-standard /proc/cpuinfo format. */ .cores = 4, .series = cpuinfo_arm_chipset_series_mediatek_mt, .model = UINT16_C(8735), .clusters = 1, .cluster_cores = { [0] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FD034), }, }, #endif #if CPUINFO_ARCH_ARM { /* * MediaTek MT6592: 4x Cortex-A7 + 4x Cortex-A7 * Some phones use non-standard /proc/cpuinfo format. */ .cores = 4, .series = cpuinfo_arm_chipset_series_mediatek_mt, .model = UINT16_C(6592), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FC074), [1] = UINT32_C(0x410FC074), }, }, { /* MediaTek MT6595: 4x Cortex-A17 + 4x Cortex-A7 */ .cores = 8, .series = cpuinfo_arm_chipset_series_mediatek_mt, .model = UINT16_C(6595), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FC075), [1] = UINT32_C(0x410FC0E0), }, }, #endif { /* MediaTek MT6797: 2x Cortex-A72 + 4x Cortex-A53 + 4x Cortex-A53 */ .cores = 10, .series = cpuinfo_arm_chipset_series_mediatek_mt, .model = UINT16_C(6797), .clusters = 3, .cluster_cores = { [0] = 4, [1] = 4, [2] = 2, }, .cluster_midr = { [0] = UINT32_C(0x410FD034), [1] = UINT32_C(0x410FD034), [2] = UINT32_C(0x410FD081), }, }, { /* MediaTek MT6799: 2x Cortex-A73 + 4x Cortex-A53 + 4x Cortex-A35 */ .cores = 10, .series = cpuinfo_arm_chipset_series_mediatek_mt, .model = UINT16_C(6799), .clusters = 3, .cluster_cores = { [0] = 4, [1] = 4, [2] = 2, }, .cluster_midr = { [0] = UINT32_C(0x410FD041), [1] = UINT32_C(0x410FD034), [2] = UINT32_C(0x410FD092), }, }, { /* Rockchip RK3399: 2x Cortex-A72 + 4x Cortex-A53 */ .cores = 6, .series = cpuinfo_arm_chipset_series_rockchip_rk, .model = UINT16_C(3399), .clusters = 2, .cluster_cores = { [0] = 4, [1] = 2, }, .cluster_midr = { [0] = UINT32_C(0x410FD034), [1] = UINT32_C(0x410FD082), }, }, #if CPUINFO_ARCH_ARM { /* Actions ATM8029: 4x Cortex-A5 * Most devices use non-standard /proc/cpuinfo format. */ .cores = 4, .series = cpuinfo_arm_chipset_series_actions_atm, .model = UINT16_C(7029), .clusters = 1, .cluster_cores = { [0] = 4, }, .cluster_midr = { [0] = UINT32_C(0x410FC051), }, }, #endif }; /* * Searches chipset name in mapping of chipset name to cores' MIDR values. If match is successful, initializes MIDR * for all clusters' leaders with tabulated values. * * @param[in] chipset - chipset (SoC) name information. * @param clusters_count - number of CPU core clusters detected in the SoC. * @param cluster_leaders - indices of core clusters' leaders in the @p processors array. * @param processors_count - number of usable logical processors in the system. * @param[in,out] processors - array of logical processor descriptions with pre-parsed MIDR, maximum frequency, * and decoded core cluster (package_leader_id) information. * Upon successful return, processors[i].midr for all clusters' leaders contains the * tabulated MIDR values. * @param verify_midr - indicated whether the function should check that the MIDR values to be assigned to leaders of * core clusters are consistent with known parts of their parsed values. * Set if to false if the only MIDR value parsed from /proc/cpuinfo is for the last processor * reported in /proc/cpuinfo and thus can't be unambiguously attributed to that processor. * * @retval true if the chipset was found in the mapping and core clusters' leaders initialized with MIDR values. * @retval false if the chipset was not found in the mapping, or any consistency check failed. */ static bool cpuinfo_arm_linux_detect_cluster_midr_by_chipset( const struct cpuinfo_arm_chipset chipset[restrict static 1], uint32_t clusters_count, const uint32_t cluster_leaders[restrict static CLUSTERS_MAX], uint32_t processors_count, struct cpuinfo_arm_linux_processor processors[restrict static processors_count], bool verify_midr) { if (clusters_count <= CLUSTERS_MAX) { for (uint32_t c = 0; c < CPUINFO_COUNT_OF(cluster_configs); c++) { if (cluster_configs[c].model == chipset->model && cluster_configs[c].series == chipset->series) { /* Verify that the total number of cores and clusters of cores matches expectation */ if (cluster_configs[c].cores != processors_count || cluster_configs[c].clusters != clusters_count) { return false; } /* Verify that core cluster configuration matches expectation */ for (uint32_t cluster = 0; cluster < clusters_count; cluster++) { const uint32_t cluster_leader = cluster_leaders[cluster]; if (cluster_configs[c].cluster_cores[cluster] != processors[cluster_leader].package_processor_count) { return false; } } if (verify_midr) { /* Verify known parts of MIDR */ for (uint32_t cluster = 0; cluster < clusters_count; cluster++) { const uint32_t cluster_leader = cluster_leaders[cluster]; /* Create a mask of known midr bits */ uint32_t midr_mask = 0; if (processors[cluster_leader].flags & CPUINFO_ARM_LINUX_VALID_IMPLEMENTER) { midr_mask |= CPUINFO_ARM_MIDR_IMPLEMENTER_MASK; } if (processors[cluster_leader].flags & CPUINFO_ARM_LINUX_VALID_VARIANT) { midr_mask |= CPUINFO_ARM_MIDR_VARIANT_MASK; } if (processors[cluster_leader].flags & CPUINFO_ARM_LINUX_VALID_PART) { midr_mask |= CPUINFO_ARM_MIDR_PART_MASK; } if (processors[cluster_leader].flags & CPUINFO_ARM_LINUX_VALID_REVISION) { midr_mask |= CPUINFO_ARM_MIDR_REVISION_MASK; } /* Verify the bits under the mask */ if ((processors[cluster_leader].midr ^ cluster_configs[c].cluster_midr[cluster]) & midr_mask) { cpuinfo_log_debug("parsed MIDR of cluster %08"PRIu32" does not match tabulated value %08"PRIu32, processors[cluster_leader].midr, cluster_configs[c].cluster_midr[cluster]); return false; } } } /* Assign MIDRs according to tabulated configurations */ for (uint32_t cluster = 0; cluster < clusters_count; cluster++) { const uint32_t cluster_leader = cluster_leaders[cluster]; processors[cluster_leader].midr = cluster_configs[c].cluster_midr[cluster]; processors[cluster_leader].flags |= CPUINFO_ARM_LINUX_VALID_MIDR; cpuinfo_log_debug("cluster %"PRIu32" MIDR = 0x%08"PRIx32, cluster, cluster_configs[c].cluster_midr[cluster]); } return true; } } } return false; } /* * Initializes MIDR for leaders of core clusters using a heuristic for big.LITTLE systems: * - If the only known MIDR is for the big core cluster, guess the matching MIDR for the LITTLE cluster. * - Estimate which of the clusters is big using maximum frequency, if known, otherwise using system processor ID. * - Initialize the MIDR for big and LITTLE core clusters using the guesstimates values. * * @param clusters_count - number of CPU core clusters detected in the SoC. * @param cluster_with_midr_count - number of CPU core clusters in the SoC with known MIDR values. * @param last_processor_with_midr - index of the last logical processor with known MIDR in the @p processors array. * @param cluster_leaders - indices of core clusters' leaders in the @p processors array. * @param[in,out] processors - array of logical processor descriptions with pre-parsed MIDR, maximum frequency, * and decoded core cluster (package_leader_id) information. * Upon successful return, processors[i].midr for all core clusters' leaders contains * the heuristically detected MIDR value. * @param verify_midr - indicated whether the function should check that the MIDR values to be assigned to leaders of * core clusters are consistent with known parts of their parsed values. * Set if to false if the only MIDR value parsed from /proc/cpuinfo is for the last processor * reported in /proc/cpuinfo and thus can't be unambiguously attributed to that processor. * * @retval true if this is a big.LITTLE system with only one known MIDR and the CPU core clusters' leaders were * initialized with MIDR values. * @retval false if this is not a big.LITTLE system. */ static bool cpuinfo_arm_linux_detect_cluster_midr_by_big_little_heuristic( uint32_t clusters_count, uint32_t cluster_with_midr_count, uint32_t last_processor_with_midr, const uint32_t cluster_leaders[restrict static CLUSTERS_MAX], struct cpuinfo_arm_linux_processor processors[restrict static last_processor_with_midr], bool verify_midr) { if (clusters_count != 2 || cluster_with_midr_count != 1) { /* Not a big.LITTLE system, or MIDR is known for both/neither clusters */ return false; } const uint32_t midr_flags = (processors[processors[last_processor_with_midr].package_leader_id].flags & CPUINFO_ARM_LINUX_VALID_MIDR); const uint32_t big_midr = processors[processors[last_processor_with_midr].package_leader_id].midr; const uint32_t little_midr = midr_little_core_for_big(big_midr); /* Default assumption: the first reported cluster is LITTLE cluster (this holds on most Linux kernels) */ uint32_t little_cluster_leader = cluster_leaders[0]; const uint32_t other_cluster_leader = cluster_leaders[1]; /* If maximum frequency is known for both clusters, assume LITTLE cluster is the one with lower frequency */ if (processors[little_cluster_leader].flags & processors[other_cluster_leader].flags & CPUINFO_LINUX_FLAG_MAX_FREQUENCY) { if (processors[little_cluster_leader].max_frequency > processors[other_cluster_leader].max_frequency) { little_cluster_leader = other_cluster_leader; } } if (verify_midr) { /* Verify known parts of MIDR */ for (uint32_t cluster = 0; cluster < clusters_count; cluster++) { const uint32_t cluster_leader = cluster_leaders[cluster]; /* Create a mask of known midr bits */ uint32_t midr_mask = 0; if (processors[cluster_leader].flags & CPUINFO_ARM_LINUX_VALID_IMPLEMENTER) { midr_mask |= CPUINFO_ARM_MIDR_IMPLEMENTER_MASK; } if (processors[cluster_leader].flags & CPUINFO_ARM_LINUX_VALID_VARIANT) { midr_mask |= CPUINFO_ARM_MIDR_VARIANT_MASK; } if (processors[cluster_leader].flags & CPUINFO_ARM_LINUX_VALID_PART) { midr_mask |= CPUINFO_ARM_MIDR_PART_MASK; } if (processors[cluster_leader].flags & CPUINFO_ARM_LINUX_VALID_REVISION) { midr_mask |= CPUINFO_ARM_MIDR_REVISION_MASK; } /* Verify the bits under the mask */ const uint32_t midr = (cluster_leader == little_cluster_leader) ? little_midr : big_midr; if ((processors[cluster_leader].midr ^ midr) & midr_mask) { cpuinfo_log_debug( "parsed MIDR %08"PRIu32" of cluster leader %"PRIu32" is inconsistent with expected value %08"PRIu32, processors[cluster_leader].midr, cluster_leader, midr); return false; } } } for (uint32_t c = 0; c < clusters_count; c++) { /* Skip cluster with already assigned MIDR */ const uint32_t cluster_leader = cluster_leaders[c]; if (bitmask_all(processors[cluster_leader].flags, CPUINFO_ARM_LINUX_VALID_MIDR)) { continue; } const uint32_t midr = (cluster_leader == little_cluster_leader) ? little_midr : big_midr; cpuinfo_log_info("assume processor %"PRIu32" to have MIDR %08"PRIx32, cluster_leader, midr); /* To be consistent, we copy the MIDR entirely, rather than by parts */ processors[cluster_leader].midr = midr; processors[cluster_leader].flags |= midr_flags; } return true; } /* * Initializes MIDR for leaders of core clusters in a single sequential scan: * - Clusters preceding the first reported MIDR value are assumed to have default MIDR value. * - Clusters following any reported MIDR value to have that MIDR value. * * @param default_midr - MIDR value that will be assigned to cluster leaders preceding any reported MIDR value. * @param processors_count - number of logical processor descriptions in the @p processors array. * @param[in,out] processors - array of logical processor descriptions with pre-parsed MIDR, maximum frequency, * and decoded core cluster (package_leader_id) information. * Upon successful return, processors[i].midr for all core clusters' leaders contains * the assigned MIDR value. */ static void cpuinfo_arm_linux_detect_cluster_midr_by_sequential_scan( uint32_t default_midr, uint32_t processors_count, struct cpuinfo_arm_linux_processor processors[restrict static processors_count]) { uint32_t midr = default_midr; for (uint32_t i = 0; i < processors_count; i++) { if (bitmask_all(processors[i].flags, CPUINFO_LINUX_FLAG_VALID)) { if (processors[i].package_leader_id == i) { if (bitmask_all(processors[i].flags, CPUINFO_ARM_LINUX_VALID_MIDR)) { midr = processors[i].midr; } else { cpuinfo_log_info("assume processor %"PRIu32" to have MIDR %08"PRIx32, i, midr); /* To be consistent, we copy the MIDR entirely, rather than by parts */ processors[i].midr = midr; processors[i].flags |= CPUINFO_ARM_LINUX_VALID_MIDR; } } } } } /* * Detects MIDR of each CPU core clusters' leader. * * @param[in] chipset - chipset (SoC) name information. * @param max_processors - number of processor descriptions in the @p processors array. * @param usable_processors - number of processor descriptions in the @p processors array with both POSSIBLE and * PRESENT flags. * @param[in,out] processors - array of logical processor descriptions with pre-parsed MIDR, maximum frequency, * and decoded core cluster (package_leader_id) information. * Upon return, processors[i].midr for all clusters' leaders contains the MIDR value. * * @returns The number of core clusters */ uint32_t cpuinfo_arm_linux_detect_cluster_midr( const struct cpuinfo_arm_chipset chipset[restrict static 1], uint32_t max_processors, uint32_t usable_processors, struct cpuinfo_arm_linux_processor processors[restrict static max_processors]) { uint32_t clusters_count = 0; uint32_t cluster_leaders[CLUSTERS_MAX]; uint32_t last_processor_in_cpuinfo = max_processors; uint32_t last_processor_with_midr = max_processors; uint32_t processors_with_midr_count = 0; for (uint32_t i = 0; i < max_processors; i++) { if (bitmask_all(processors[i].flags, CPUINFO_LINUX_FLAG_VALID)) { if (processors[i].flags & CPUINFO_ARM_LINUX_VALID_PROCESSOR) { last_processor_in_cpuinfo = i; } if (bitmask_all(processors[i].flags, CPUINFO_ARM_LINUX_VALID_IMPLEMENTER | CPUINFO_ARM_LINUX_VALID_PART)) { last_processor_with_midr = i; processors_with_midr_count += 1; } const uint32_t group_leader = processors[i].package_leader_id; if (group_leader == i) { if (clusters_count < CLUSTERS_MAX) { cluster_leaders[clusters_count] = i; } clusters_count += 1; } else { /* Copy known bits of information to cluster leader */ if ((processors[i].flags & ~processors[group_leader].flags) & CPUINFO_LINUX_FLAG_MAX_FREQUENCY) { processors[group_leader].max_frequency = processors[i].max_frequency; processors[group_leader].flags |= CPUINFO_LINUX_FLAG_MAX_FREQUENCY; } if (!bitmask_all(processors[group_leader].flags, CPUINFO_ARM_LINUX_VALID_MIDR) && bitmask_all(processors[i].flags, CPUINFO_ARM_LINUX_VALID_MIDR)) { processors[group_leader].midr = processors[i].midr; processors[group_leader].flags |= CPUINFO_ARM_LINUX_VALID_MIDR; } } } } cpuinfo_log_debug("detected %"PRIu32" core clusters", clusters_count); /* * Two relations between reported /proc/cpuinfo information, and cores is possible: * - /proc/cpuinfo reports information for all or some of the cores below the corresponding * "processor : " lines. Information on offline cores may be missing. * - /proc/cpuinfo reports information only once, after all "processor : " lines. * The reported information may relate to processor #0 or to the processor which * executed the system calls to read /proc/cpuinfo. It is also indistinguishable * from /proc/cpuinfo reporting information only for the last core (e.g. if all other * cores are offline). * * We detect the second case by checking if /proc/cpuinfo contains valid MIDR only for one, * last reported, processor. Note, that the last reported core may be not the last * present & possible processor, as /proc/cpuinfo may non-report high-index offline cores. */ if (processors_with_midr_count == 1 && last_processor_in_cpuinfo == last_processor_with_midr && clusters_count > 1) { /* * There are multiple core clusters, but /proc/cpuinfo reported MIDR only for one * processor, and we don't even know which logical processor this information refers to. * * We make three attempts to detect MIDR for all clusters: * 1. Search tabulated MIDR values for chipsets which have heterogeneous clusters and ship with Linux * kernels which do not always report all cores in /proc/cpuinfo. If found, use the tabulated values. * 2. For systems with 2 clusters and MIDR known for one cluster, assume big.LITTLE configuration, * and estimate MIDR for the other cluster under assumption that MIDR for the big cluster is known. * 3. Initialize MIDRs for all core clusters to the only parsed MIDR value. */ cpuinfo_log_debug("the only reported MIDR can not be attributed to a particular processor"); if (cpuinfo_arm_linux_detect_cluster_midr_by_chipset( chipset, clusters_count, cluster_leaders, usable_processors, processors, false)) { return clusters_count; } /* Try big.LITTLE heuristic */ if (cpuinfo_arm_linux_detect_cluster_midr_by_big_little_heuristic( clusters_count, 1, last_processor_with_midr, cluster_leaders, processors, false)) { return clusters_count; } /* Fall back to sequential initialization of MIDR values for core clusters */ cpuinfo_arm_linux_detect_cluster_midr_by_sequential_scan( processors[processors[last_processor_with_midr].package_leader_id].midr, max_processors, processors); } else if (processors_with_midr_count < usable_processors) { /* * /proc/cpuinfo reported MIDR only for some processors, and probably some core clusters do not have MIDR * for any of the cores. Check if this is the case. */ uint32_t clusters_with_midr_count = 0; for (uint32_t i = 0; i < max_processors; i++) { if (bitmask_all(processors[i].flags, CPUINFO_LINUX_FLAG_VALID | CPUINFO_ARM_LINUX_VALID_MIDR)) { if (processors[i].package_leader_id == i) { clusters_with_midr_count += 1; } } } if (clusters_with_midr_count < clusters_count) { /* * /proc/cpuinfo reported MIDR only for some clusters, need to reconstruct others. * We make three attempts to detect MIDR for clusters without it: * 1. Search tabulated MIDR values for chipsets which have heterogeneous clusters and ship with Linux * kernels which do not always report all cores in /proc/cpuinfo. If found, use the tabulated values. * 2. For systems with 2 clusters and MIDR known for one cluster, assume big.LITTLE configuration, * and estimate MIDR for the other cluster under assumption that MIDR for the big cluster is known. * 3. Initialize MIDRs for core clusters in a single sequential scan: * - Clusters preceding the first reported MIDR value are assumed to have the last reported MIDR value. * - Clusters following any reported MIDR value to have that MIDR value. */ if (cpuinfo_arm_linux_detect_cluster_midr_by_chipset( chipset, clusters_count, cluster_leaders, usable_processors, processors, true)) { return clusters_count; } if (last_processor_with_midr != max_processors) { /* Try big.LITTLE heuristic */ if (cpuinfo_arm_linux_detect_cluster_midr_by_big_little_heuristic( clusters_count, processors_with_midr_count, last_processor_with_midr, cluster_leaders, processors, true)) { return clusters_count; } /* Fall back to sequential initialization of MIDR values for core clusters */ cpuinfo_arm_linux_detect_cluster_midr_by_sequential_scan( processors[processors[last_processor_with_midr].package_leader_id].midr, max_processors, processors); } } } return clusters_count; }