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