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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/riscv/kernel/cpu.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
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.c108
1 files changed, 108 insertions, 0 deletions
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
new file mode 100644
index 000000000..ca6c81e54
--- /dev/null
+++ b/arch/riscv/kernel/cpu.c
@@ -0,0 +1,108 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/init.h>
+#include <linux/seq_file.h>
+#include <linux/of.h>
+
+/* Return -1 if not a valid hart */
+int riscv_of_processor_hart(struct device_node *node)
+{
+ const char *isa, *status;
+ u32 hart;
+
+ if (!of_device_is_compatible(node, "riscv")) {
+ pr_warn("Found incompatible CPU\n");
+ return -(ENODEV);
+ }
+
+ if (of_property_read_u32(node, "reg", &hart)) {
+ pr_warn("Found CPU without hart ID\n");
+ return -(ENODEV);
+ }
+ if (hart >= NR_CPUS) {
+ pr_info("Found hart ID %d, which is above NR_CPUs. Disabling this hart\n", hart);
+ return -(ENODEV);
+ }
+
+ if (of_property_read_string(node, "status", &status)) {
+ pr_warn("CPU with hartid=%d has no \"status\" property\n", hart);
+ return -(ENODEV);
+ }
+ if (strcmp(status, "okay")) {
+ pr_info("CPU with hartid=%d has a non-okay status of \"%s\"\n", hart, status);
+ return -(ENODEV);
+ }
+
+ if (of_property_read_string(node, "riscv,isa", &isa)) {
+ pr_warn("CPU with hartid=%d has no \"riscv,isa\" property\n", hart);
+ return -(ENODEV);
+ }
+ if (isa[0] != 'r' || isa[1] != 'v') {
+ pr_warn("CPU with hartid=%d has an invalid ISA of \"%s\"\n", hart, isa);
+ return -(ENODEV);
+ }
+
+ return hart;
+}
+
+#ifdef CONFIG_PROC_FS
+
+static void *c_start(struct seq_file *m, loff_t *pos)
+{
+ *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 hart_id = (unsigned long)v - 1;
+ struct device_node *node = of_get_cpu_node(hart_id, NULL);
+ const char *compat, *isa, *mmu;
+
+ seq_printf(m, "hart\t: %lu\n", hart_id);
+ if (!of_property_read_string(node, "riscv,isa", &isa)
+ && isa[0] == 'r'
+ && isa[1] == 'v')
+ seq_printf(m, "isa\t: %s\n", isa);
+ if (!of_property_read_string(node, "mmu-type", &mmu)
+ && !strncmp(mmu, "riscv,", 6))
+ seq_printf(m, "mmu\t: %s\n", mmu+6);
+ if (!of_property_read_string(node, "compatible", &compat)
+ && strcmp(compat, "riscv"))
+ seq_printf(m, "uarch\t: %s\n", compat);
+ 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 */