1 /*
2  * Copyright (c) 2017-2019, Arm Limited and Contributors. All rights reserved.
3  * Copyright (c) 2022-2023, Advanced Micro Devices, Inc. All rights reserved.
4  *
5  * SPDX-License-Identifier: BSD-3-Clause
6  */
7 
8 /*
9  * Top-level SMC handler for ZynqMP IPI Mailbox doorbell functions.
10  */
11 
12 #include <errno.h>
13 #include <string.h>
14 
15 #include <common/debug.h>
16 #include <common/runtime_svc.h>
17 #include <lib/bakery_lock.h>
18 #include <lib/mmio.h>
19 
20 #include <ipi.h>
21 #include "ipi_mailbox_svc.h"
22 #include <plat_ipi.h>
23 #include <plat_private.h>
24 
25 /*********************************************************************
26  * Macros definitions
27  ********************************************************************/
28 
29 /* IPI SMC calls macros: */
30 #define IPI_SMC_OPEN_IRQ_MASK		0x00000001U /* IRQ enable bit in IPI
31 						     * open SMC call
32 						     */
33 #define IPI_SMC_NOTIFY_BLOCK_MASK	0x00000001U /* Flag to indicate if
34 						     * IPI notification needs
35 						     * to be blocking.
36 						     */
37 #define IPI_SMC_ENQUIRY_DIRQ_MASK	0x00000001U /* Flag to indicate if
38 						     * notification interrupt
39 						     * to be disabled.
40 						     */
41 #define IPI_SMC_ACK_EIRQ_MASK		0x00000001U /* Flag to indicate if
42 						     * notification interrupt
43 						     * to be enable.
44 						     */
45 
46 #define UNSIGNED32_MASK			0xFFFFFFFFU /* 32bit mask */
47 
48 /**
49  * ipi_smc_handler() - SMC handler for IPI SMC calls.
50  * @smc_fid: Function identifier.
51  * @x1: Arguments.
52  * @x2: Arguments.
53  * @x3: Arguments.
54  * @x4: Arguments.
55  * @cookie: Unused.
56  * @handle: Pointer to caller's context structure.
57  * @flags: SECURE_FLAG or NON_SECURE_FLAG.
58  *
59  * Return: Unused.
60  *
61  * Determines that smc_fid is valid and supported PM SMC Function ID from the
62  * list of pm_api_ids, otherwise completes the request with
63  * the unknown SMC Function ID.
64  *
65  * The SMC calls for PM service are forwarded from SIP Service SMC handler
66  * function with rt_svc_handle signature.
67  *
68  */
ipi_smc_handler(uint32_t smc_fid,uint64_t x1,uint64_t x2,uint64_t x3,uint64_t x4,const void * cookie,void * handle,uint64_t flags)69 uint64_t ipi_smc_handler(uint32_t smc_fid, uint64_t x1, uint64_t x2,
70 			 uint64_t x3, uint64_t x4, const void *cookie,
71 			 void *handle, uint64_t flags)
72 {
73 	int32_t ret;
74 	uint32_t ipi_local_id;
75 	uint32_t ipi_remote_id;
76 	uint32_t is_secure;
77 
78 	ipi_local_id = x1 & UNSIGNED32_MASK;
79 	ipi_remote_id = x2 & UNSIGNED32_MASK;
80 
81 	/* OEN Number 48 to 63 is for Trusted App and OS
82 	 * GET_SMC_OEN limits the return value of OEN number to 63 by bitwise
83 	 * AND operation with 0x3F.
84 	 * Upper limit check for OEN value is not required.
85 	 */
86 	if (GET_SMC_OEN(smc_fid) >= OEN_TAP_START) {
87 		is_secure = 1;
88 	} else {
89 		is_secure = 0;
90 	}
91 
92 	/* Validate IPI mailbox access */
93 	ret = ipi_mb_validate(ipi_local_id, ipi_remote_id, is_secure);
94 	if (ret)
95 		SMC_RET1(handle, ret);
96 
97 	switch (GET_SMC_NUM(smc_fid)) {
98 	case IPI_MAILBOX_OPEN:
99 		ipi_mb_open(ipi_local_id, ipi_remote_id);
100 		SMC_RET1(handle, 0);
101 	case IPI_MAILBOX_RELEASE:
102 		ipi_mb_release(ipi_local_id, ipi_remote_id);
103 		SMC_RET1(handle, 0);
104 	case IPI_MAILBOX_STATUS_ENQUIRY:
105 	{
106 		int32_t disable_irq;
107 
108 		disable_irq = (x3 & IPI_SMC_ENQUIRY_DIRQ_MASK) ? 1 : 0;
109 		ret = ipi_mb_enquire_status(ipi_local_id, ipi_remote_id);
110 		if ((ret & IPI_MB_STATUS_RECV_PENDING) && disable_irq)
111 			ipi_mb_disable_irq(ipi_local_id, ipi_remote_id);
112 		SMC_RET1(handle, ret);
113 	}
114 	case IPI_MAILBOX_NOTIFY:
115 	{
116 		uint32_t is_blocking;
117 
118 		is_blocking = (x3 & IPI_SMC_NOTIFY_BLOCK_MASK) ? 1 : 0;
119 		ipi_mb_notify(ipi_local_id, ipi_remote_id, is_blocking);
120 		SMC_RET1(handle, 0);
121 	}
122 	case IPI_MAILBOX_ACK:
123 	{
124 		int32_t enable_irq;
125 
126 		enable_irq = (x3 & IPI_SMC_ACK_EIRQ_MASK) ? 1 : 0;
127 		ipi_mb_ack(ipi_local_id, ipi_remote_id);
128 		if (enable_irq)
129 			ipi_mb_enable_irq(ipi_local_id, ipi_remote_id);
130 		SMC_RET1(handle, 0);
131 	}
132 	case IPI_MAILBOX_ENABLE_IRQ:
133 		ipi_mb_enable_irq(ipi_local_id, ipi_remote_id);
134 		SMC_RET1(handle, 0);
135 	case IPI_MAILBOX_DISABLE_IRQ:
136 		ipi_mb_disable_irq(ipi_local_id, ipi_remote_id);
137 		SMC_RET1(handle, 0);
138 	default:
139 		WARN("Unimplemented IPI service call: 0x%x\n", smc_fid);
140 		SMC_RET1(handle, SMC_UNK);
141 	}
142 }
143