1 // SPDX-License-Identifier: GPL-2.0+
2 /**
3 * (C) Copyright 2014, Cavium Inc.
4 * (C) Copyright 2017, Xilinx Inc.
5 *
6 **/
7
8 #include <asm-offsets.h>
9 #include <config.h>
10 #include <version.h>
11 #include <asm/macro.h>
12 #include <asm/psci.h>
13 #include <asm/system.h>
14
15 /*
16 * Issue the hypervisor call
17 *
18 * x0~x7: input arguments
19 * x0~x3: output arguments
20 */
hvc_call(struct pt_regs * args)21 static void hvc_call(struct pt_regs *args)
22 {
23 asm volatile(
24 "ldr x0, %0\n"
25 "ldr x1, %1\n"
26 "ldr x2, %2\n"
27 "ldr x3, %3\n"
28 "ldr x4, %4\n"
29 "ldr x5, %5\n"
30 "ldr x6, %6\n"
31 "ldr x7, %7\n"
32 "hvc #0\n"
33 "str x0, %0\n"
34 "str x1, %1\n"
35 "str x2, %2\n"
36 "str x3, %3\n"
37 : "+m" (args->regs[0]), "+m" (args->regs[1]),
38 "+m" (args->regs[2]), "+m" (args->regs[3])
39 : "m" (args->regs[4]), "m" (args->regs[5]),
40 "m" (args->regs[6]), "m" (args->regs[7])
41 : "x0", "x1", "x2", "x3", "x4", "x5", "x6", "x7",
42 "x8", "x9", "x10", "x11", "x12", "x13", "x14", "x15",
43 "x16", "x17");
44 }
45
46 /*
47 * void smc_call(arg0, arg1...arg7)
48 *
49 * issue the secure monitor call
50 *
51 * x0~x7: input arguments
52 * x0~x3: output arguments
53 */
54
smc_call(struct pt_regs * args)55 void smc_call(struct pt_regs *args)
56 {
57 asm volatile(
58 "ldr x0, %0\n"
59 "ldr x1, %1\n"
60 "ldr x2, %2\n"
61 "ldr x3, %3\n"
62 "ldr x4, %4\n"
63 "ldr x5, %5\n"
64 "ldr x6, %6\n"
65 "smc #0\n"
66 "str x0, %0\n"
67 "str x1, %1\n"
68 "str x2, %2\n"
69 "str x3, %3\n"
70 : "+m" (args->regs[0]), "+m" (args->regs[1]),
71 "+m" (args->regs[2]), "+m" (args->regs[3])
72 : "m" (args->regs[4]), "m" (args->regs[5]),
73 "m" (args->regs[6])
74 : "x0", "x1", "x2", "x3", "x4", "x5", "x6", "x7",
75 "x8", "x9", "x10", "x11", "x12", "x13", "x14", "x15",
76 "x16", "x17");
77 }
78
79 /*
80 * For now, all systems we support run at least in EL2 and thus
81 * trigger PSCI calls to EL3 using SMC. If anyone ever wants to
82 * use PSCI on U-Boot running below a hypervisor, please detect
83 * this and set the flag accordingly.
84 */
85 static const bool use_smc_for_psci = true;
86
psci_system_reset(void)87 void __noreturn psci_system_reset(void)
88 {
89 struct pt_regs regs;
90
91 regs.regs[0] = ARM_PSCI_0_2_FN_SYSTEM_RESET;
92
93 if (use_smc_for_psci)
94 smc_call(®s);
95 else
96 hvc_call(®s);
97
98 while (1)
99 ;
100 }
101
psci_system_off(void)102 void __noreturn psci_system_off(void)
103 {
104 struct pt_regs regs;
105
106 regs.regs[0] = ARM_PSCI_0_2_FN_SYSTEM_OFF;
107
108 if (use_smc_for_psci)
109 smc_call(®s);
110 else
111 hvc_call(®s);
112
113 while (1)
114 ;
115 }
116