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// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
* Copyright (C) 2020, Sean Anderson <seanga2@gmail.com>
*/
#include <clk.h>
#include <common.h>
#include <cpu.h>
#include <dm.h>
#include <errno.h>
#include <log.h>
#include <dm/device-internal.h>
#include <dm/lists.h>
#include <linux/bitops.h>
#include <linux/err.h>
DECLARE_GLOBAL_DATA_PTR;
static int riscv_cpu_get_desc(struct udevice *dev, char *buf, int size)
{
const char *isa;
isa = dev_read_string(dev, "riscv,isa");
if (size < (strlen(isa) + 1))
return -ENOSPC;
strcpy(buf, isa);
return 0;
}
static int riscv_cpu_get_info(struct udevice *dev, struct cpu_info *info)
{
int ret;
struct clk clk;
const char *mmu;
/* Zero out the frequency, in case sizeof(ulong) != sizeof(u32) */
info->cpu_freq = 0;
/* First try getting the frequency from the assigned clock */
ret = clk_get_by_index(dev, 0, &clk);
if (!ret) {
ret = clk_get_rate(&clk);
if (!IS_ERR_VALUE(ret))
info->cpu_freq = ret;
clk_free(&clk);
}
if (!info->cpu_freq)
dev_read_u32(dev, "clock-frequency", (u32 *)&info->cpu_freq);
mmu = dev_read_string(dev, "mmu-type");
if (!mmu)
info->features |= BIT(CPU_FEAT_MMU);
return 0;
}
static int riscv_cpu_get_count(struct udevice *dev)
{
ofnode node;
int num = 0;
ofnode_for_each_subnode(node, dev_ofnode(dev->parent)) {
const char *device_type;
/* skip if hart is marked as not available in the device tree */
if (!ofnode_is_available(node))
continue;
device_type = ofnode_read_string(node, "device_type");
if (!device_type)
continue;
if (strcmp(device_type, "cpu") == 0)
num++;
}
return num;
}
static int riscv_cpu_bind(struct udevice *dev)
{
struct cpu_platdata *plat = dev_get_parent_platdata(dev);
struct driver *drv;
int ret;
/* save the hart id */
plat->cpu_id = dev_read_addr(dev);
/* first examine the property in current cpu node */
ret = dev_read_u32(dev, "timebase-frequency", &plat->timebase_freq);
/* if not found, then look at the parent /cpus node */
if (ret)
dev_read_u32(dev->parent, "timebase-frequency",
&plat->timebase_freq);
/*
* Bind riscv-timer driver on boot hart.
*
* We only instantiate one timer device which is enough for U-Boot.
* Pass the "timebase-frequency" value as the driver data for the
* timer device.
*
* Return value is not checked since it's possible that the timer
* driver is not included.
*/
if (plat->cpu_id == gd->arch.boot_hart && plat->timebase_freq) {
drv = lists_driver_lookup_name("riscv_timer");
if (!drv) {
debug("Cannot find the timer driver, not included?\n");
return 0;
}
device_bind_with_driver_data(dev, drv, "riscv_timer",
plat->timebase_freq, ofnode_null(),
NULL);
}
return 0;
}
static int riscv_cpu_probe(struct udevice *dev)
{
int ret = 0;
struct clk clk;
/* Get a clock if it exists */
ret = clk_get_by_index(dev, 0, &clk);
if (ret)
return 0;
ret = clk_enable(&clk);
clk_free(&clk);
if (ret == -ENOSYS || ret == -ENOTSUPP)
return 0;
else
return ret;
}
static const struct cpu_ops riscv_cpu_ops = {
.get_desc = riscv_cpu_get_desc,
.get_info = riscv_cpu_get_info,
.get_count = riscv_cpu_get_count,
};
static const struct udevice_id riscv_cpu_ids[] = {
{ .compatible = "riscv" },
{ }
};
U_BOOT_DRIVER(riscv_cpu) = {
.name = "riscv_cpu",
.id = UCLASS_CPU,
.of_match = riscv_cpu_ids,
.bind = riscv_cpu_bind,
.probe = riscv_cpu_probe,
.ops = &riscv_cpu_ops,
.flags = DM_FLAG_PRE_RELOC,
};
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