ARM: aspeed: Enable SMP boot
[muen/linux.git] / arch / arm / mach-aspeed / platsmp.c
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
13 static struct device_node *secboot_node;
14
15 static int aspeed_g6_boot_secondary(unsigned int cpu, struct task_struct *idle)
16 {
17         void __iomem *base;
18
19         base = of_iomap(secboot_node, 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(base);
32
33         return 0;
34 }
35
36 static 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, "aspeed,ast2600-smpmem");
41         if (!secboot_node) {
42                 pr_err("secboot device node found!!\n");
43                 return;
44         }
45
46         base = of_iomap(secboot_node, 0);
47         if (!base) {
48                 pr_err("could not map the secondary boot base!");
49                 return;
50         }
51         __raw_writel(0xBADABABA, base + BOOT_SIG);
52
53         iounmap(base);
54 }
55
56 static 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
61 CPU_METHOD_OF_DECLARE(aspeed_smp, "aspeed,ast2600-smp", &aspeed_smp_ops);