mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-06-09 23:36:03 +09:00
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
/*
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* Copyright (C) 2015, Miao Yan <yanmiaobest@gmail.com>
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*
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* SPDX-License-Identifier: GPL-2.0+
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*/
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#include <common.h>
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#include <cpu.h>
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#include <dm.h>
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#include <errno.h>
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#include <asm/cpu.h>
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#include <asm/fw_cfg.h>
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DECLARE_GLOBAL_DATA_PTR;
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int cpu_qemu_get_desc(struct udevice *dev, char *buf, int size)
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{
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if (size < CPU_MAX_NAME_LEN)
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return -ENOSPC;
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cpu_get_name(buf);
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return 0;
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}
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static int cpu_qemu_get_count(struct udevice *dev)
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{
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return qemu_fwcfg_online_cpus();
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}
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static const struct cpu_ops cpu_qemu_ops = {
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.get_desc = cpu_qemu_get_desc,
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.get_count = cpu_qemu_get_count,
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};
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static const struct udevice_id cpu_qemu_ids[] = {
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{ .compatible = "cpu-qemu" },
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{ }
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};
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U_BOOT_DRIVER(cpu_qemu_drv) = {
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.name = "cpu_qemu",
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.id = UCLASS_CPU,
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.of_match = cpu_qemu_ids,
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.ops = &cpu_qemu_ops,
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};
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