// SPDX-License-Identifier: GPL-2.0-or-later /* * Low-level power-management support for Alpine platform. * * Copyright (C) 2015 Annapurna Labs Ltd. */ #include <linux/io.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/regmap.h> #include <linux/mfd/syscon.h> #include "alpine_cpu_pm.h" #include "alpine_cpu_resume.h" /* NB registers */ #define AL_SYSFAB_POWER_CONTROL(cpu) (0x2000 + (cpu)*0x100 + 0x20) static struct regmap *al_sysfabric; static struct al_cpu_resume_regs __iomem *al_cpu_resume_regs; static int wakeup_supported; int alpine_cpu_wakeup(unsigned int phys_cpu, uint32_t phys_resume_addr) { if (!wakeup_supported) return -ENOSYS; /* * Set CPU resume address - * secure firmware running on boot will jump to this address * after setting proper CPU mode, and initializing e.g. secure * regs (the same mode all CPUs are booted to - usually HYP) */ writel(phys_resume_addr, &al_cpu_resume_regs->per_cpu[phys_cpu].resume_addr); /* Power-up the CPU */ regmap_write(al_sysfabric, AL_SYSFAB_POWER_CONTROL(phys_cpu), 0); return 0; } void __init alpine_cpu_pm_init(void) { struct device_node *np; uint32_t watermark; al_sysfabric = syscon_regmap_lookup_by_compatible("al,alpine-sysfabric-service"); np = of_find_compatible_node(NULL, NULL, "al,alpine-cpu-resume"); al_cpu_resume_regs = of_iomap(np, 0); wakeup_supported = !IS_ERR(al_sysfabric) && al_cpu_resume_regs; if (wakeup_supported) { watermark = readl(&al_cpu_resume_regs->watermark); wakeup_supported = (watermark & AL_CPU_RESUME_MAGIC_NUM_MASK) == AL_CPU_RESUME_MAGIC_NUM; } }