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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/arm/kernel/devtree.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm/kernel/devtree.c')
-rw-r--r-- | arch/arm/kernel/devtree.c | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c new file mode 100644 index 000000000..264827281 --- /dev/null +++ b/arch/arm/kernel/devtree.c @@ -0,0 +1,239 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/arch/arm/kernel/devtree.c + * + * Copyright (C) 2009 Canonical Ltd. <jeremy.kerr@canonical.com> + */ + +#include <linux/init.h> +#include <linux/export.h> +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/memblock.h> +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/smp.h> + +#include <asm/cputype.h> +#include <asm/setup.h> +#include <asm/page.h> +#include <asm/prom.h> +#include <asm/smp_plat.h> +#include <asm/mach/arch.h> +#include <asm/mach-types.h> + + +#ifdef CONFIG_SMP +extern struct of_cpu_method __cpu_method_of_table[]; + +static const struct of_cpu_method __cpu_method_of_table_sentinel + __used __section("__cpu_method_of_table_end"); + + +static int __init set_smp_ops_by_method(struct device_node *node) +{ + const char *method; + struct of_cpu_method *m = __cpu_method_of_table; + + if (of_property_read_string(node, "enable-method", &method)) + return 0; + + for (; m->method; m++) + if (!strcmp(m->method, method)) { + smp_set_ops(m->ops); + return 1; + } + + return 0; +} +#else +static inline int set_smp_ops_by_method(struct device_node *node) +{ + return 1; +} +#endif + + +/* + * 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; + int found_method = 0; + 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] = MPIDR_INVALID }; + bool bootcpu_valid = false; + cpus = of_find_node_by_path("/cpus"); + + if (!cpus) + return; + + for_each_of_cpu_node(cpu) { + u32 hwid = of_get_cpu_hwid(cpu, 0); + + pr_debug(" * %pOF...\n", cpu); + + /* + * Bits n:24 must be set to 0 in the DT since the reg property + * defines the MPIDR[23:0]. + */ + if (hwid & ~MPIDR_HWID_BITMASK) { + of_node_put(cpu); + 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")) { + of_node_put(cpu); + 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++; + } + + if (WARN(cpuidx > nr_cpu_ids, "DT /cpu %u nodes greater than " + "max cores %u, capping them\n", + cpuidx, nr_cpu_ids)) { + cpuidx = nr_cpu_ids; + of_node_put(cpu); + break; + } + + tmp_map[i] = hwid; + + if (!found_method) + found_method = set_smp_ops_by_method(cpu); + } + + /* + * Fallback to an enable-method in the cpus node if nothing found in + * a cpu node. + */ + if (!found_method) + set_smp_ops_by_method(cpus); + + if (!bootcpu_valid) { + pr_warn("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)); + } +} + +bool arch_match_cpu_phys_id(int cpu, u64 phys_id) +{ + return phys_id == cpu_logical_map(cpu); +} + +static const void * __init arch_get_next_mach(const char *const **match) +{ + static const struct machine_desc *mdesc = __arch_info_begin; + const struct machine_desc *m = mdesc; + + if (m >= __arch_info_end) + return NULL; + + mdesc++; + *match = m->dt_compat; + return m; +} + +/** + * setup_machine_fdt - Machine setup when an dtb was passed to the kernel + * @dt_virt: virtual address of dt blob + * + * If a dtb was passed to the kernel in r2, then use it to choose the + * correct machine_desc and to setup the system. + */ +const struct machine_desc * __init setup_machine_fdt(void *dt_virt) +{ + const struct machine_desc *mdesc, *mdesc_best = NULL; + + DT_MACHINE_START(GENERIC_DT, "Generic DT based system") + .l2c_aux_val = 0x0, + .l2c_aux_mask = ~0x0, + MACHINE_END + + mdesc_best = &__mach_desc_GENERIC_DT; + + if (!dt_virt || !early_init_dt_verify(dt_virt)) + return NULL; + + mdesc = of_flat_dt_match_machine(mdesc_best, arch_get_next_mach); + + if (!mdesc) { + const char *prop; + int size; + unsigned long dt_root; + + early_print("\nError: unrecognized/unsupported " + "device tree compatible list:\n[ "); + + dt_root = of_get_flat_dt_root(); + prop = of_get_flat_dt_prop(dt_root, "compatible", &size); + while (size > 0) { + early_print("'%s' ", prop); + size -= strlen(prop) + 1; + prop += strlen(prop) + 1; + } + early_print("]\n\n"); + + dump_machine_table(); /* does not return */ + } + + /* We really don't want to do this, but sometimes firmware provides buggy data */ + if (mdesc->dt_fixup) + mdesc->dt_fixup(); + + early_init_dt_scan_nodes(); + + /* Change machine number to match the mdesc we're using */ + __machine_arch_type = mdesc->nr; + + return mdesc; +} |