1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/delay.h>
3 #include <linux/init.h>
4 #include <linux/smp.h>
5 #include "smc.h"
6
tango_boot_secondary(unsigned int cpu,struct task_struct * idle)7 static int tango_boot_secondary(unsigned int cpu, struct task_struct *idle)
8 {
9 tango_set_aux_boot_addr(__pa_symbol(secondary_startup));
10 tango_start_aux_core(cpu);
11 return 0;
12 }
13
14 #ifdef CONFIG_HOTPLUG_CPU
15 /*
16 * cpu_kill() and cpu_die() run concurrently on different cores.
17 * Firmware will only "kill" a core once it has properly "died".
18 * Try a few times to kill a core before giving up, and sleep
19 * between tries to give that core enough time to die.
20 */
tango_cpu_kill(unsigned int cpu)21 static int tango_cpu_kill(unsigned int cpu)
22 {
23 int i, err;
24
25 for (i = 0; i < 10; ++i) {
26 msleep(10);
27 err = tango_aux_core_kill(cpu);
28 if (!err)
29 return true;
30 }
31
32 return false;
33 }
34
tango_cpu_die(unsigned int cpu)35 static void tango_cpu_die(unsigned int cpu)
36 {
37 while (tango_aux_core_die(cpu) < 0)
38 cpu_relax();
39
40 panic("cpu %d failed to die\n", cpu);
41 }
42 #endif
43
44 static const struct smp_operations tango_smp_ops __initconst = {
45 .smp_boot_secondary = tango_boot_secondary,
46 #ifdef CONFIG_HOTPLUG_CPU
47 .cpu_kill = tango_cpu_kill,
48 .cpu_die = tango_cpu_die,
49 #endif
50 };
51
52 CPU_METHOD_OF_DECLARE(tango4_smp, "sigma,tango4-smp", &tango_smp_ops);
53
