mirror of
https://github.com/smaeul/u-boot.git
synced 2025-10-30 03:28:16 +00:00
de752c5e73
Currently, when booting with more that one CPU enabled, U-Boot scans 'cpu' node in device tree and calculates CPU number. This does not scale well as changing CPU number also requires modifying .dts and re-compiling U-Boot. This patch uses fw_cfg interface provided by QEMU to detect online CPU number at runtime, and dynamically adds 'cpu' device to U-Boot's driver model. Signed-off-by: Miao Yan <yanmiaobest@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org> Reviewed-by: Bin Meng <bmeng.cn@gmail.com> Tested-by: Bin Meng <bmeng.cn@gmail.com>
47 lines
821 B
C
47 lines
821 B
C
/*
|
|
* Copyright (C) 2015, Miao Yan <yanmiaobest@gmail.com>
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0+
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <cpu.h>
|
|
#include <dm.h>
|
|
#include <errno.h>
|
|
#include <asm/cpu.h>
|
|
#include <asm/fw_cfg.h>
|
|
|
|
DECLARE_GLOBAL_DATA_PTR;
|
|
|
|
int cpu_qemu_get_desc(struct udevice *dev, char *buf, int size)
|
|
{
|
|
if (size < CPU_MAX_NAME_LEN)
|
|
return -ENOSPC;
|
|
|
|
cpu_get_name(buf);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int cpu_qemu_get_count(struct udevice *dev)
|
|
{
|
|
return qemu_fwcfg_online_cpus();
|
|
}
|
|
|
|
static const struct cpu_ops cpu_qemu_ops = {
|
|
.get_desc = cpu_qemu_get_desc,
|
|
.get_count = cpu_qemu_get_count,
|
|
};
|
|
|
|
static const struct udevice_id cpu_qemu_ids[] = {
|
|
{ .compatible = "cpu-qemu" },
|
|
{ }
|
|
};
|
|
|
|
U_BOOT_DRIVER(cpu_qemu_drv) = {
|
|
.name = "cpu_qemu",
|
|
.id = UCLASS_CPU,
|
|
.of_match = cpu_qemu_ids,
|
|
.ops = &cpu_qemu_ops,
|
|
};
|