157 lines
3.7 KiB
C
157 lines
3.7 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Copyright (C) 2012 Regents of the University of California
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/seq_file.h>
|
|
#include <linux/of.h>
|
|
#include <asm/smp.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)
|
|
{
|
|
const char *isa;
|
|
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 (!of_device_is_available(node)) {
|
|
pr_info("CPU with hartid=%d is not available\n", hart);
|
|
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 print_isa(struct seq_file *f, const char *orig_isa)
|
|
{
|
|
static const char *ext = "mafdcsu";
|
|
const char *isa = orig_isa;
|
|
const char *e;
|
|
|
|
/*
|
|
* Linux doesn't support rv32e or rv128i, and we only support booting
|
|
* kernels on harts with the same ISA that the kernel is compiled for.
|
|
*/
|
|
#if defined(CONFIG_32BIT)
|
|
if (strncmp(isa, "rv32i", 5) != 0)
|
|
return;
|
|
#elif defined(CONFIG_64BIT)
|
|
if (strncmp(isa, "rv64i", 5) != 0)
|
|
return;
|
|
#endif
|
|
|
|
/* Print the base ISA, as we already know it's legal. */
|
|
seq_puts(f, "isa\t\t: ");
|
|
seq_write(f, isa, 5);
|
|
isa += 5;
|
|
|
|
/*
|
|
* Check the rest of the ISA string for valid extensions, printing those
|
|
* we find. RISC-V ISA strings define an order, so we only print the
|
|
* extension bits when they're in order. Hide the supervisor (S)
|
|
* extension from userspace as it's not accessible from there.
|
|
*/
|
|
for (e = ext; *e != '\0'; ++e) {
|
|
if (isa[0] == e[0]) {
|
|
if (isa[0] != 's')
|
|
seq_write(f, isa, 1);
|
|
|
|
isa++;
|
|
}
|
|
}
|
|
seq_puts(f, "\n");
|
|
|
|
/*
|
|
* If we were given an unsupported ISA in the device tree then print
|
|
* a bit of info describing what went wrong.
|
|
*/
|
|
if (isa[0] != '\0')
|
|
pr_info("unsupported ISA \"%s\" in device tree\n", orig_isa);
|
|
}
|
|
|
|
static void print_mmu(struct seq_file *f, const char *mmu_type)
|
|
{
|
|
#if defined(CONFIG_32BIT)
|
|
if (strcmp(mmu_type, "riscv,sv32") != 0)
|
|
return;
|
|
#elif defined(CONFIG_64BIT)
|
|
if (strcmp(mmu_type, "riscv,sv39") != 0 &&
|
|
strcmp(mmu_type, "riscv,sv48") != 0)
|
|
return;
|
|
#endif
|
|
|
|
seq_printf(f, "mmu\t\t: %s\n", mmu_type+6);
|
|
}
|
|
|
|
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 cpu_id = (unsigned long)v - 1;
|
|
struct device_node *node = of_get_cpu_node(cpu_id, NULL);
|
|
const char *compat, *isa, *mmu;
|
|
|
|
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);
|
|
if (!of_property_read_string(node, "mmu-type", &mmu))
|
|
print_mmu(m, mmu);
|
|
if (!of_property_read_string(node, "compatible", &compat)
|
|
&& strcmp(compat, "riscv"))
|
|
seq_printf(m, "uarch\t\t: %s\n", compat);
|
|
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 */
|