| 1 | // SPDX-License-Identifier: GPL-2.0-only |
|---|---|
| 2 | /* |
| 3 | * OMAP4 SMP cpu-hotplug support |
| 4 | * |
| 5 | * Copyright (C) 2010 Texas Instruments, Inc. |
| 6 | * Author: |
| 7 | * Santosh Shilimkar <santosh.shilimkar@ti.com> |
| 8 | * |
| 9 | * Platform file needed for the OMAP4 SMP. This file is based on arm |
| 10 | * realview smp platform. |
| 11 | * Copyright (c) 2002 ARM Limited. |
| 12 | */ |
| 13 | |
| 14 | #include <linux/kernel.h> |
| 15 | #include <linux/errno.h> |
| 16 | #include <linux/smp.h> |
| 17 | #include <linux/io.h> |
| 18 | |
| 19 | #include "omap-wakeupgen.h" |
| 20 | #include "common.h" |
| 21 | #include "powerdomain.h" |
| 22 | |
| 23 | /* |
| 24 | * platform-specific code to shutdown a CPU |
| 25 | * Called with IRQs disabled |
| 26 | */ |
| 27 | void omap4_cpu_die(unsigned int cpu) |
| 28 | { |
| 29 | unsigned int boot_cpu = 0; |
| 30 | void __iomem *base = omap_get_wakeupgen_base(); |
| 31 | |
| 32 | /* |
| 33 | * we're ready for shutdown now, so do it |
| 34 | */ |
| 35 | if (omap_secure_apis_support()) { |
| 36 | if (omap_modify_auxcoreboot0(set_mask: 0x0, clear_mask: 0x200) != 0x0) |
| 37 | pr_err("Secure clear status failed\n"); |
| 38 | } else { |
| 39 | writel_relaxed(0, base + OMAP_AUX_CORE_BOOT_0); |
| 40 | } |
| 41 | |
| 42 | |
| 43 | for (;;) { |
| 44 | /* |
| 45 | * Enter into low power state |
| 46 | */ |
| 47 | omap4_hotplug_cpu(cpu, PWRDM_POWER_OFF); |
| 48 | |
| 49 | if (omap_secure_apis_support()) |
| 50 | boot_cpu = omap_read_auxcoreboot0() >> 9; |
| 51 | else |
| 52 | boot_cpu = |
| 53 | readl_relaxed(base + OMAP_AUX_CORE_BOOT_0) >> 5; |
| 54 | |
| 55 | if (boot_cpu == smp_processor_id()) { |
| 56 | /* |
| 57 | * OK, proper wakeup, we're done |
| 58 | */ |
| 59 | break; |
| 60 | } |
| 61 | pr_debug("CPU%u: spurious wakeup call\n", cpu); |
| 62 | } |
| 63 | } |
| 64 | |
| 65 | /* Needed by kexec and platform_can_cpu_hotplug() */ |
| 66 | int omap4_cpu_kill(unsigned int cpu) |
| 67 | { |
| 68 | return 1; |
| 69 | } |
| 70 |