linux-stable/arch/arm/mach-aspeed/platsmp.c
Joel Stanley 87dfe49691 ARM: aspeed: Enable SMP boot
This brings the secondary CPU into Linux. It depends on the setup
performed by ASPEED's u-boot.

Signed-off-by: Joel Stanley <joel@jms.id.au>
2019-08-25 23:26:52 +09:30

62 lines
1.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
// Copyright (C) ASPEED Technology Inc.
// Copyright IBM Corp.
#include <linux/of_address.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/smp.h>
#define BOOT_ADDR 0x00
#define BOOT_SIG 0x04
static struct device_node *secboot_node;
static int aspeed_g6_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
void __iomem *base;
base = of_iomap(secboot_node, 0);
if (!base) {
pr_err("could not map the secondary boot base!");
return -ENODEV;
}
writel_relaxed(0, base + BOOT_ADDR);
writel_relaxed(__pa_symbol(secondary_startup_arm), base + BOOT_ADDR);
writel_relaxed((0xABBAAB00 | (cpu & 0xff)), base + BOOT_SIG);
dsb_sev();
iounmap(base);
return 0;
}
static void __init aspeed_g6_smp_prepare_cpus(unsigned int max_cpus)
{
void __iomem *base;
secboot_node = of_find_compatible_node(NULL, NULL, "aspeed,ast2600-smpmem");
if (!secboot_node) {
pr_err("secboot device node found!!\n");
return;
}
base = of_iomap(secboot_node, 0);
if (!base) {
pr_err("could not map the secondary boot base!");
return;
}
__raw_writel(0xBADABABA, base + BOOT_SIG);
iounmap(base);
}
static const struct smp_operations aspeed_smp_ops __initconst = {
.smp_prepare_cpus = aspeed_g6_smp_prepare_cpus,
.smp_boot_secondary = aspeed_g6_boot_secondary,
};
CPU_METHOD_OF_DECLARE(aspeed_smp, "aspeed,ast2600-smp", &aspeed_smp_ops);