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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/riscv/kernel/cpu.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | arch/riscv/kernel/cpu.c | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c new file mode 100644 index 000000000..0f76181dc --- /dev/null +++ b/arch/riscv/kernel/cpu.c @@ -0,0 +1,267 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2012 Regents of the University of California + */ + +#include <linux/cpu.h> +#include <linux/init.h> +#include <linux/seq_file.h> +#include <linux/of.h> +#include <asm/csr.h> +#include <asm/hwcap.h> +#include <asm/sbi.h> +#include <asm/smp.h> +#include <asm/pgtable.h> + +/* + * Returns the hart ID of the given device tree node, or -ENODEV if the node + * isn't an enabled and valid RISC-V hart node. + */ +int riscv_of_processor_hartid(struct device_node *node, unsigned long *hart) +{ + const char *isa; + + if (!of_device_is_compatible(node, "riscv")) { + pr_warn("Found incompatible CPU\n"); + return -ENODEV; + } + + *hart = (unsigned long) of_get_cpu_hwid(node, 0); + if (*hart == ~0UL) { + pr_warn("Found CPU without hart ID\n"); + return -ENODEV; + } + + if (!of_device_is_available(node)) { + pr_info("CPU with hartid=%lu is not available\n", *hart); + return -ENODEV; + } + + if (of_property_read_string(node, "riscv,isa", &isa)) { + pr_warn("CPU with hartid=%lu has no \"riscv,isa\" property\n", *hart); + return -ENODEV; + } + if (isa[0] != 'r' || isa[1] != 'v') { + pr_warn("CPU with hartid=%lu has an invalid ISA of \"%s\"\n", *hart, isa); + return -ENODEV; + } + + return 0; +} + +/* + * Find hart ID of the CPU DT node under which given DT node falls. + * + * To achieve this, we walk up the DT tree until we find an active + * RISC-V core (HART) node and extract the cpuid from it. + */ +int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid) +{ + for (; node; node = node->parent) { + if (of_device_is_compatible(node, "riscv")) { + *hartid = (unsigned long)of_get_cpu_hwid(node, 0); + if (*hartid == ~0UL) { + pr_warn("Found CPU without hart ID\n"); + return -ENODEV; + } + return 0; + } + } + + return -1; +} + +#ifdef CONFIG_PROC_FS + +struct riscv_cpuinfo { + unsigned long mvendorid; + unsigned long marchid; + unsigned long mimpid; +}; +static DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo); + +static int riscv_cpuinfo_starting(unsigned int cpu) +{ + struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo); + +#if IS_ENABLED(CONFIG_RISCV_SBI) + ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid(); + ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid(); + ci->mimpid = sbi_spec_is_0_1() ? 0 : sbi_get_mimpid(); +#elif IS_ENABLED(CONFIG_RISCV_M_MODE) + ci->mvendorid = csr_read(CSR_MVENDORID); + ci->marchid = csr_read(CSR_MARCHID); + ci->mimpid = csr_read(CSR_MIMPID); +#else + ci->mvendorid = 0; + ci->marchid = 0; + ci->mimpid = 0; +#endif + + return 0; +} + +static int __init riscv_cpuinfo_init(void) +{ + int ret; + + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "riscv/cpuinfo:starting", + riscv_cpuinfo_starting, NULL); + if (ret < 0) { + pr_err("cpuinfo: failed to register hotplug callbacks.\n"); + return ret; + } + + return 0; +} +device_initcall(riscv_cpuinfo_init); + +#define __RISCV_ISA_EXT_DATA(UPROP, EXTID) \ + { \ + .uprop = #UPROP, \ + .isa_ext_id = EXTID, \ + } +/* + * Here are the ordering rules of extension naming defined by RISC-V + * specification : + * 1. All extensions should be separated from other multi-letter extensions + * by an underscore. + * 2. The first letter following the 'Z' conventionally indicates the most + * closely related alphabetical extension category, IMAFDQLCBKJTPVH. + * If multiple 'Z' extensions are named, they should be ordered first + * by category, then alphabetically within a category. + * 3. Standard supervisor-level extensions (starts with 'S') should be + * listed after standard unprivileged extensions. If multiple + * supervisor-level extensions are listed, they should be ordered + * alphabetically. + * 4. Non-standard extensions (starts with 'X') must be listed after all + * standard extensions. They must be separated from other multi-letter + * extensions by an underscore. + */ +static struct riscv_isa_ext_data isa_ext_arr[] = { + __RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF), + __RISCV_ISA_EXT_DATA(sstc, RISCV_ISA_EXT_SSTC), + __RISCV_ISA_EXT_DATA(svinval, RISCV_ISA_EXT_SVINVAL), + __RISCV_ISA_EXT_DATA(svpbmt, RISCV_ISA_EXT_SVPBMT), + __RISCV_ISA_EXT_DATA(zicbom, RISCV_ISA_EXT_ZICBOM), + __RISCV_ISA_EXT_DATA(zihintpause, RISCV_ISA_EXT_ZIHINTPAUSE), + __RISCV_ISA_EXT_DATA("", RISCV_ISA_EXT_MAX), +}; + +static void print_isa_ext(struct seq_file *f) +{ + struct riscv_isa_ext_data *edata; + int i = 0, arr_sz; + + arr_sz = ARRAY_SIZE(isa_ext_arr) - 1; + + /* No extension support available */ + if (arr_sz <= 0) + return; + + for (i = 0; i <= arr_sz; i++) { + edata = &isa_ext_arr[i]; + if (!__riscv_isa_extension_available(NULL, edata->isa_ext_id)) + continue; + seq_printf(f, "_%s", edata->uprop); + } +} + +/* + * These are the only valid base (single letter) ISA extensions as per the spec. + * It also specifies the canonical order in which it appears in the spec. + * Some of the extension may just be a place holder for now (B, K, P, J). + * This should be updated once corresponding extensions are ratified. + */ +static const char base_riscv_exts[13] = "imafdqcbkjpvh"; + +static void print_isa(struct seq_file *f, const char *isa) +{ + int i; + + seq_puts(f, "isa\t\t: "); + /* Print the rv[64/32] part */ + seq_write(f, isa, 4); + for (i = 0; i < sizeof(base_riscv_exts); i++) { + if (__riscv_isa_extension_available(NULL, base_riscv_exts[i] - 'a')) + /* Print only enabled the base ISA extensions */ + seq_write(f, &base_riscv_exts[i], 1); + } + print_isa_ext(f); + seq_puts(f, "\n"); +} + +static void print_mmu(struct seq_file *f) +{ + char sv_type[16]; + +#ifdef CONFIG_MMU +#if defined(CONFIG_32BIT) + strncpy(sv_type, "sv32", 5); +#elif defined(CONFIG_64BIT) + if (pgtable_l5_enabled) + strncpy(sv_type, "sv57", 5); + else if (pgtable_l4_enabled) + strncpy(sv_type, "sv48", 5); + else + strncpy(sv_type, "sv39", 5); +#endif +#else + strncpy(sv_type, "none", 5); +#endif /* CONFIG_MMU */ + seq_printf(f, "mmu\t\t: %s\n", sv_type); +} + +static void *c_start(struct seq_file *m, loff_t *pos) +{ + if (*pos == nr_cpu_ids) + return NULL; + + *pos = cpumask_next(*pos - 1, cpu_online_mask); + if ((*pos) < nr_cpu_ids) + return (void *)(uintptr_t)(1 + *pos); + return NULL; +} + +static void *c_next(struct seq_file *m, void *v, loff_t *pos) +{ + (*pos)++; + return c_start(m, pos); +} + +static void c_stop(struct seq_file *m, void *v) +{ +} + +static int c_show(struct seq_file *m, void *v) +{ + unsigned long cpu_id = (unsigned long)v - 1; + struct device_node *node = of_get_cpu_node(cpu_id, NULL); + struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id); + const char *compat, *isa; + + seq_printf(m, "processor\t: %lu\n", cpu_id); + seq_printf(m, "hart\t\t: %lu\n", cpuid_to_hartid_map(cpu_id)); + if (!of_property_read_string(node, "riscv,isa", &isa)) + print_isa(m, isa); + print_mmu(m); + if (!of_property_read_string(node, "compatible", &compat) + && strcmp(compat, "riscv")) + seq_printf(m, "uarch\t\t: %s\n", compat); + seq_printf(m, "mvendorid\t: 0x%lx\n", ci->mvendorid); + seq_printf(m, "marchid\t\t: 0x%lx\n", ci->marchid); + seq_printf(m, "mimpid\t\t: 0x%lx\n", ci->mimpid); + seq_puts(m, "\n"); + of_node_put(node); + + return 0; +} + +const struct seq_operations cpuinfo_op = { + .start = c_start, + .next = c_next, + .stop = c_stop, + .show = c_show +}; + +#endif /* CONFIG_PROC_FS */ |