1// SPDX-License-Identifier: GPL-2.0-or-later
2// Copyright (C) ASPEED Technology Inc.
3// Copyright IBM Corp.
4
5#include <linux/of_address.h>
6#include <linux/io.h>
7#include <linux/of.h>
8#include <linux/smp.h>
9
10#define BOOT_ADDR 0x00
11#define BOOT_SIG 0x04
12
13static struct device_node *secboot_node;
14
15static int aspeed_g6_boot_secondary(unsigned int cpu, struct task_struct *idle)
16{
17 void __iomem *base;
18
19 base = of_iomap(node: secboot_node, index: 0);
20 if (!base) {
21 pr_err("could not map the secondary boot base!");
22 return -ENODEV;
23 }
24
25 writel_relaxed(0, base + BOOT_ADDR);
26 writel_relaxed(__pa_symbol(secondary_startup_arm), base + BOOT_ADDR);
27 writel_relaxed((0xABBAAB00 | (cpu & 0xff)), base + BOOT_SIG);
28
29 dsb_sev();
30
31 iounmap(addr: base);
32
33 return 0;
34}
35
36static void __init aspeed_g6_smp_prepare_cpus(unsigned int max_cpus)
37{
38 void __iomem *base;
39
40 secboot_node = of_find_compatible_node(NULL, NULL, compat: "aspeed,ast2600-smpmem");
41 if (!secboot_node) {
42 pr_err("secboot device node found!!\n");
43 return;
44 }
45
46 base = of_iomap(node: secboot_node, index: 0);
47 if (!base) {
48 pr_err("could not map the secondary boot base!");
49 return;
50 }
51 __raw_writel(val: 0xBADABABA, addr: base + BOOT_SIG);
52
53 iounmap(addr: base);
54}
55
56static const struct smp_operations aspeed_smp_ops __initconst = {
57 .smp_prepare_cpus = aspeed_g6_smp_prepare_cpus,
58 .smp_boot_secondary = aspeed_g6_boot_secondary,
59};
60
61CPU_METHOD_OF_DECLARE(aspeed_smp, "aspeed,ast2600-smp", &aspeed_smp_ops);
62

source code of linux/arch/arm/mach-aspeed/platsmp.c