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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/riscv/kernel/cpu.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/riscv/kernel/cpu.c')
-rw-r--r--arch/riscv/kernel/cpu.c308
1 files changed, 308 insertions, 0 deletions
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
new file mode 100644
index 0000000000..157ace8b26
--- /dev/null
+++ b/arch/riscv/kernel/cpu.c
@@ -0,0 +1,308 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ */
+
+#include <linux/acpi.h>
+#include <linux/cpu.h>
+#include <linux/ctype.h>
+#include <linux/init.h>
+#include <linux/seq_file.h>
+#include <linux/of.h>
+#include <asm/acpi.h>
+#include <asm/cpufeature.h>
+#include <asm/csr.h>
+#include <asm/hwcap.h>
+#include <asm/sbi.h>
+#include <asm/smp.h>
+#include <asm/pgtable.h>
+
+bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
+{
+ return phys_id == cpuid_to_hartid_map(cpu);
+}
+
+/*
+ * 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)
+{
+ int cpu;
+
+ *hart = (unsigned long)of_get_cpu_hwid(node, 0);
+ if (*hart == ~0UL) {
+ pr_warn("Found CPU without hart ID\n");
+ return -ENODEV;
+ }
+
+ cpu = riscv_hartid_to_cpuid(*hart);
+ if (cpu < 0)
+ return cpu;
+
+ if (!cpu_possible(cpu))
+ return -ENODEV;
+
+ return 0;
+}
+
+int __init riscv_early_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-base", &isa))
+ goto old_interface;
+
+ if (IS_ENABLED(CONFIG_32BIT) && strncasecmp(isa, "rv32i", 5)) {
+ pr_warn("CPU with hartid=%lu does not support rv32i", *hart);
+ return -ENODEV;
+ }
+
+ if (IS_ENABLED(CONFIG_64BIT) && strncasecmp(isa, "rv64i", 5)) {
+ pr_warn("CPU with hartid=%lu does not support rv64i", *hart);
+ return -ENODEV;
+ }
+
+ if (!of_property_present(node, "riscv,isa-extensions"))
+ return -ENODEV;
+
+ if (of_property_match_string(node, "riscv,isa-extensions", "i") < 0 ||
+ of_property_match_string(node, "riscv,isa-extensions", "m") < 0 ||
+ of_property_match_string(node, "riscv,isa-extensions", "a") < 0) {
+ pr_warn("CPU with hartid=%lu does not support ima", *hart);
+ return -ENODEV;
+ }
+
+ return 0;
+
+old_interface:
+ if (!riscv_isa_fallback) {
+ pr_warn("CPU with hartid=%lu is invalid: this kernel does not parse \"riscv,isa\"",
+ *hart);
+ return -ENODEV;
+ }
+
+ if (of_property_read_string(node, "riscv,isa", &isa)) {
+ pr_warn("CPU with hartid=%lu has no \"riscv,isa-base\" or \"riscv,isa\" property\n",
+ *hart);
+ return -ENODEV;
+ }
+
+ if (IS_ENABLED(CONFIG_32BIT) && strncasecmp(isa, "rv32ima", 7)) {
+ pr_warn("CPU with hartid=%lu does not support rv32ima", *hart);
+ return -ENODEV;
+ }
+
+ if (IS_ENABLED(CONFIG_64BIT) && strncasecmp(isa, "rv64ima", 7)) {
+ pr_warn("CPU with hartid=%lu does not support rv64ima", *hart);
+ 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;
+}
+
+DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
+
+unsigned long riscv_cached_mvendorid(unsigned int cpu_id)
+{
+ struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id);
+
+ return ci->mvendorid;
+}
+EXPORT_SYMBOL(riscv_cached_mvendorid);
+
+unsigned long riscv_cached_marchid(unsigned int cpu_id)
+{
+ struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id);
+
+ return ci->marchid;
+}
+EXPORT_SYMBOL(riscv_cached_marchid);
+
+unsigned long riscv_cached_mimpid(unsigned int cpu_id)
+{
+ struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id);
+
+ return ci->mimpid;
+}
+EXPORT_SYMBOL(riscv_cached_mimpid);
+
+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;
+}
+arch_initcall(riscv_cpuinfo_init);
+
+#ifdef CONFIG_PROC_FS
+
+static void print_isa(struct seq_file *f)
+{
+ seq_puts(f, "isa\t\t: ");
+
+ if (IS_ENABLED(CONFIG_32BIT))
+ seq_write(f, "rv32", 4);
+ else
+ seq_write(f, "rv64", 4);
+
+ for (int i = 0; i < riscv_isa_ext_count; i++) {
+ if (!__riscv_isa_extension_available(NULL, riscv_isa_ext[i].id))
+ continue;
+
+ /* Only multi-letter extensions are split by underscores */
+ if (strnlen(riscv_isa_ext[i].name, 2) != 1)
+ seq_puts(f, "_");
+
+ seq_printf(f, "%s", riscv_isa_ext[i].name);
+ }
+
+ seq_puts(f, "\n");
+}
+
+static void print_mmu(struct seq_file *f)
+{
+ const char *sv_type;
+
+#ifdef CONFIG_MMU
+#if defined(CONFIG_32BIT)
+ sv_type = "sv32";
+#elif defined(CONFIG_64BIT)
+ if (pgtable_l5_enabled)
+ sv_type = "sv57";
+ else if (pgtable_l4_enabled)
+ sv_type = "sv48";
+ else
+ sv_type = "sv39";
+#endif
+#else
+ sv_type = "none";
+#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 riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id);
+ struct device_node *node;
+ const char *compat;
+
+ seq_printf(m, "processor\t: %lu\n", cpu_id);
+ seq_printf(m, "hart\t\t: %lu\n", cpuid_to_hartid_map(cpu_id));
+ print_isa(m);
+ print_mmu(m);
+
+ if (acpi_disabled) {
+ node = of_get_cpu_node(cpu_id, NULL);
+
+ if (!of_property_read_string(node, "compatible", &compat) &&
+ strcmp(compat, "riscv"))
+ seq_printf(m, "uarch\t\t: %s\n", compat);
+
+ of_node_put(node);
+ }
+
+ 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");
+
+ return 0;
+}
+
+const struct seq_operations cpuinfo_op = {
+ .start = c_start,
+ .next = c_next,
+ .stop = c_stop,
+ .show = c_show
+};
+
+#endif /* CONFIG_PROC_FS */