1 /** @file
2 Reset System lib using PSCI hypervisor or secure monitor calls
3
4 Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
5 Copyright (c) 2013, ARM Ltd. All rights reserved.<BR>
6 Copyright (c) 2014-2020, Linaro Ltd. All rights reserved.<BR>
7 Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
8
9 SPDX-License-Identifier: BSD-2-Clause-Patent
10
11 **/
12
13 #include <PiPei.h>
14
15 #include <libfdt.h>
16 #include <Library/ArmHvcLib.h>
17 #include <Library/ArmSmcLib.h>
18 #include <Library/BaseLib.h>
19 #include <Library/DebugLib.h>
20 #include <Library/HobLib.h>
21 #include <Library/ResetSystemLib.h>
22
23 #include <IndustryStandard/ArmStdSmc.h>
24
25 typedef enum {
26 PsciMethodUnknown,
27 PsciMethodSmc,
28 PsciMethodHvc,
29 } PSCI_METHOD;
30
31 STATIC
32 PSCI_METHOD
DiscoverPsciMethod(VOID)33 DiscoverPsciMethod (
34 VOID
35 )
36 {
37 VOID *DeviceTreeBase;
38 INT32 Node, Prev;
39 INT32 Len;
40 CONST CHAR8 *Compatible;
41 CONST CHAR8 *CompatibleItem;
42 CONST VOID *Prop;
43
44 DeviceTreeBase = (VOID*)(UINTN)PcdGet64 (PcdDeviceTreeInitialBaseAddress);
45 ASSERT (fdt_check_header (DeviceTreeBase) == 0);
46
47 //
48 // Enumerate all FDT nodes looking for the PSCI node and capture the method
49 //
50 for (Prev = 0;; Prev = Node) {
51 Node = fdt_next_node (DeviceTreeBase, Prev, NULL);
52 if (Node < 0) {
53 break;
54 }
55
56 Compatible = fdt_getprop (DeviceTreeBase, Node, "compatible", &Len);
57 if (Compatible == NULL) {
58 continue;
59 }
60
61 //
62 // Iterate over the NULL-separated items in the compatible string
63 //
64 for (CompatibleItem = Compatible; CompatibleItem < Compatible + Len;
65 CompatibleItem += 1 + AsciiStrLen (CompatibleItem)) {
66
67 if (AsciiStrCmp (CompatibleItem, "arm,psci-0.2") != 0) {
68 continue;
69 }
70
71 Prop = fdt_getprop (DeviceTreeBase, Node, "method", NULL);
72 if (!Prop) {
73 DEBUG ((DEBUG_ERROR, "%a: Missing PSCI method property\n",
74 __FUNCTION__));
75 return PsciMethodUnknown;
76 }
77
78 if (AsciiStrnCmp (Prop, "hvc", 3) == 0) {
79 return PsciMethodHvc;
80 } else if (AsciiStrnCmp (Prop, "smc", 3) == 0) {
81 return PsciMethodSmc;
82 } else {
83 DEBUG ((DEBUG_ERROR, "%a: Unknown PSCI method \"%a\"\n", __FUNCTION__,
84 Prop));
85 return PsciMethodUnknown;
86 }
87 }
88 }
89 return PsciMethodUnknown;
90 }
91
92 STATIC
93 VOID
PerformPsciAction(IN UINTN Arg0)94 PerformPsciAction (
95 IN UINTN Arg0
96 )
97 {
98 ARM_SMC_ARGS ArmSmcArgs;
99 ARM_HVC_ARGS ArmHvcArgs;
100
101 ArmSmcArgs.Arg0 = Arg0;
102 ArmHvcArgs.Arg0 = Arg0;
103
104 switch (DiscoverPsciMethod ()) {
105 case PsciMethodHvc:
106 ArmCallHvc (&ArmHvcArgs);
107 break;
108
109 case PsciMethodSmc:
110 ArmCallSmc (&ArmSmcArgs);
111 break;
112
113 default:
114 DEBUG ((DEBUG_ERROR, "%a: no PSCI method defined\n", __FUNCTION__));
115 ASSERT (FALSE);
116 }
117 }
118
119 /**
120 This function causes a system-wide reset (cold reset), in which
121 all circuitry within the system returns to its initial state. This type of reset
122 is asynchronous to system operation and operates without regard to
123 cycle boundaries.
124
125 If this function returns, it means that the system does not support cold reset.
126 **/
127 VOID
128 EFIAPI
ResetCold(VOID)129 ResetCold (
130 VOID
131 )
132 {
133 // Send a PSCI 0.2 SYSTEM_RESET command
134 PerformPsciAction (ARM_SMC_ID_PSCI_SYSTEM_RESET);
135 }
136
137 /**
138 This function causes a system-wide initialization (warm reset), in which all processors
139 are set to their initial state. Pending cycles are not corrupted.
140
141 If this function returns, it means that the system does not support warm reset.
142 **/
143 VOID
144 EFIAPI
ResetWarm(VOID)145 ResetWarm (
146 VOID
147 )
148 {
149 // Map a warm reset into a cold reset
150 ResetCold ();
151 }
152
153 /**
154 This function causes the system to enter a power state equivalent
155 to the ACPI G2/S5 or G3 states.
156
157 If this function returns, it means that the system does not support shutdown reset.
158 **/
159 VOID
160 EFIAPI
ResetShutdown(VOID)161 ResetShutdown (
162 VOID
163 )
164 {
165 // Send a PSCI 0.2 SYSTEM_OFF command
166 PerformPsciAction (ARM_SMC_ID_PSCI_SYSTEM_OFF);
167 }
168
169 /**
170 This function causes a systemwide reset. The exact type of the reset is
171 defined by the EFI_GUID that follows the Null-terminated Unicode string passed
172 into ResetData. If the platform does not recognize the EFI_GUID in ResetData
173 the platform must pick a supported reset type to perform.The platform may
174 optionally log the parameters from any non-normal reset that occurs.
175
176 @param[in] DataSize The size, in bytes, of ResetData.
177 @param[in] ResetData The data buffer starts with a Null-terminated string,
178 followed by the EFI_GUID.
179 **/
180 VOID
181 EFIAPI
ResetPlatformSpecific(IN UINTN DataSize,IN VOID * ResetData)182 ResetPlatformSpecific (
183 IN UINTN DataSize,
184 IN VOID *ResetData
185 )
186 {
187 // Map the platform specific reset as reboot
188 ResetCold ();
189 }
190
191 /**
192 The ResetSystem function resets the entire platform.
193
194 @param[in] ResetType The type of reset to perform.
195 @param[in] ResetStatus The status code for the reset.
196 @param[in] DataSize The size, in bytes, of ResetData.
197 @param[in] ResetData For a ResetType of EfiResetCold, EfiResetWarm, or EfiResetShutdown
198 the data buffer starts with a Null-terminated string, optionally
199 followed by additional binary data. The string is a description
200 that the caller may use to further indicate the reason for the
201 system reset.
202 **/
203 VOID
204 EFIAPI
ResetSystem(IN EFI_RESET_TYPE ResetType,IN EFI_STATUS ResetStatus,IN UINTN DataSize,IN VOID * ResetData OPTIONAL)205 ResetSystem (
206 IN EFI_RESET_TYPE ResetType,
207 IN EFI_STATUS ResetStatus,
208 IN UINTN DataSize,
209 IN VOID *ResetData OPTIONAL
210 )
211 {
212 switch (ResetType) {
213 case EfiResetWarm:
214 ResetWarm ();
215 break;
216
217 case EfiResetCold:
218 ResetCold ();
219 break;
220
221 case EfiResetShutdown:
222 ResetShutdown ();
223 return;
224
225 case EfiResetPlatformSpecific:
226 ResetPlatformSpecific (DataSize, ResetData);
227 return;
228
229 default:
230 return;
231 }
232 }
233