1 /** @file
2 *
3 *  Copyright (c) 2011-2014, ARM Limited. All rights reserved.
4 *
5 *  This program and the accompanying materials
6 *  are licensed and made available under the terms and conditions of the BSD License
7 *  which accompanies this distribution.  The full text of the license may be found at
8 *  http://opensource.org/licenses/bsd-license.php
9 *
10 *  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
11 *  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
12 *
13 **/
14 
15 #include <PiPei.h>
16 
17 #include <Library/ArmLib.h>
18 #include <Library/ArmGicLib.h>
19 #include <Library/ArmPlatformLib.h>
20 #include <Library/ArmPlatformSecLib.h>
21 #include <Library/DebugLib.h>
22 #include <Library/PcdLib.h>
23 #include <Library/PrintLib.h>
24 #include <Library/SerialPortLib.h>
25 
26 // When the firmware is built as not Standalone, the secondary cores need to wait the firmware
27 // entirely written into DRAM. It is the firmware from DRAM which will wake up the secondary cores.
28 VOID
NonSecureWaitForFirmware(VOID)29 NonSecureWaitForFirmware (
30   VOID
31   )
32 {
33   VOID (*SecondaryStart)(VOID);
34   UINTN AcknowledgeInterrupt;
35   UINTN InterruptId;
36 
37   // The secondary cores will execute the firmware once wake from WFI.
38   SecondaryStart = (VOID (*)())(UINTN)PcdGet64 (PcdFvBaseAddress);
39 
40   ArmCallWFI ();
41 
42   // Acknowledge the interrupt and send End of Interrupt signal.
43   AcknowledgeInterrupt = ArmGicAcknowledgeInterrupt (PcdGet32 (PcdGicInterruptInterfaceBase), &InterruptId);
44   // Check if it is a valid interrupt ID
45   if (InterruptId < ArmGicGetMaxNumInterrupts (PcdGet32 (PcdGicDistributorBase))) {
46     // Got a valid SGI number hence signal End of Interrupt
47     ArmGicEndOfInterrupt (PcdGet32 (PcdGicInterruptInterfaceBase), AcknowledgeInterrupt);
48   }
49 
50   // Jump to secondary core entry point.
51   SecondaryStart ();
52 
53   // PEI Core should always load and never return
54   ASSERT (FALSE);
55 }
56 
57 /**
58   Call before jumping to Normal World
59 
60   This function allows the firmware platform to do extra actions before
61   jumping to the Normal World
62 
63 **/
64 VOID
ArmPlatformSecExtraAction(IN UINTN MpId,OUT UINTN * JumpAddress)65 ArmPlatformSecExtraAction (
66   IN  UINTN         MpId,
67   OUT UINTN*        JumpAddress
68   )
69 {
70   CHAR8           Buffer[100];
71   UINTN           CharCount;
72   UINTN*          StartAddress;
73 
74   if (FeaturePcdGet (PcdStandalone) == FALSE) {
75 
76     //
77     // Warning: This code assumes the DRAM has already been initialized by ArmPlatformSecLib
78     //
79 
80     if (ArmPlatformIsPrimaryCore (MpId)) {
81       StartAddress = (UINTN*)(UINTN)PcdGet64 (PcdFvBaseAddress);
82 
83       // Patch the DRAM to make an infinite loop at the start address
84       *StartAddress = 0xEAFFFFFE; // opcode for while(1)
85 
86       CharCount = AsciiSPrint (Buffer,sizeof (Buffer),"Waiting for firmware at 0x%08X ...\n\r",StartAddress);
87       SerialPortWrite ((UINT8 *) Buffer, CharCount);
88 
89       *JumpAddress = PcdGet64 (PcdFvBaseAddress);
90     } else {
91       // When the primary core is stopped by the hardware debugger to copy the firmware
92       // into DRAM. The secondary cores are still running. As soon as the first bytes of
93       // the firmware are written into DRAM, the secondary cores will start to execute the
94       // code even if the firmware is not entirely written into the memory.
95       // That's why the secondary cores need to be parked in WFI and wake up once the
96       // firmware is ready.
97 
98       *JumpAddress = (UINTN)NonSecureWaitForFirmware;
99     }
100   } else if (FeaturePcdGet (PcdSystemMemoryInitializeInSec)) {
101 
102     //
103     // Warning: This code assumes the DRAM has already been initialized by ArmPlatformSecLib
104     //
105 
106     if (ArmPlatformIsPrimaryCore (MpId)) {
107       // Signal the secondary cores they can jump to PEI phase
108       ArmGicSendSgiTo (PcdGet32 (PcdGicDistributorBase), ARM_GIC_ICDSGIR_FILTER_EVERYONEELSE, 0x0E, PcdGet32 (PcdGicSgiIntId));
109 
110       // To enter into Non Secure state, we need to make a return from exception
111       *JumpAddress = PcdGet64 (PcdFvBaseAddress);
112     } else {
113       // We wait for the primary core to finish to initialize the System Memory. Otherwise the secondary
114       // cores would make crash the system by setting their stacks in DRAM before the primary core has not
115       // finished to initialize the system memory.
116       *JumpAddress = (UINTN)NonSecureWaitForFirmware;
117     }
118   } else {
119     *JumpAddress = PcdGet64 (PcdFvBaseAddress);
120   }
121 }
122