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(0x0, 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 }