1 // SPDX-License-Identifier: BSD-2-Clause 2 /* 3 * Copyright (c) 2015-2019, Arm Limited and Contributors. All rights reserved. 4 * Copyright (c) 2019-2020, Linaro Limited 5 */ 6 #include <assert.h> 7 #include <drivers/scmi-msg.h> 8 #include <drivers/scmi.h> 9 #include <io.h> 10 #include <kernel/misc.h> 11 #include <stdbool.h> 12 #include <stdint.h> 13 #include <string.h> 14 #include <trace.h> 15 #include <util.h> 16 17 #include "common.h" 18 19 #define SCMI_PAYLOAD_U32_MAX (SCMI_SEC_PAYLOAD_SIZE / sizeof(uint32_t)) 20 21 /** 22 * struct smt_header - SMT formatted header for SMT base shared memory transfer 23 * 24 * @status: Bit flags, see SMT_STATUS_* 25 * @flags: Bit flags, see SMT_FLAG_* 26 * @length: Byte size of message payload (variable) + ::message_header (32bit) 27 * payload: SCMI message payload data 28 */ 29 struct smt_header { 30 uint32_t reserved0; 31 uint32_t status; 32 uint64_t reserved1; 33 uint32_t flags; 34 uint32_t length; /* message_header + payload */ 35 uint32_t message_header; 36 uint32_t payload[]; 37 }; 38 39 /* Flag set in smt_header::status when SMT does not contain pending message */ 40 #define SMT_STATUS_FREE BIT(0) 41 /* Flag set in smt_header::status when SMT reports an error */ 42 #define SMT_STATUS_ERROR BIT(1) 43 44 /* Flag set in smt_header::flags when SMT uses interrupts */ 45 #define SMT_FLAG_INTR_ENABLED BIT(1) 46 47 /* Bit fields packed in smt_header::message_header */ 48 #define SMT_MSG_ID_MASK GENMASK_32(7, 0) 49 #define SMT_HDR_MSG_ID(_hdr) ((_hdr) & SMT_MSG_ID_MASK) 50 51 #define SMT_MSG_TYPE_MASK GENMASK_32(9, 8) 52 #define SMT_HDR_TYPE_ID(_hdr) (((_hdr) & SMT_MSG_TYPE_MASK) >> 8) 53 54 #define SMT_MSG_PROT_ID_MASK GENMASK_32(17, 10) 55 #define SMT_HDR_PROT_ID(_hdr) (((_hdr) & SMT_MSG_PROT_ID_MASK) >> 10) 56 57 static struct smt_header *channel_to_smt_hdr(struct scmi_msg_channel *chan) 58 { 59 return (struct smt_header *)io_pa_or_va(&chan->shm_addr, 60 sizeof(struct smt_header)); 61 } 62 63 /* 64 * Creates a SCMI message instance in secure memory and push it in the SCMI 65 * message drivers. Message structure contains SCMI protocol meta-data and 66 * references to input payload in secure memory and output message buffer 67 * in shared memory. 68 */ 69 static void scmi_process_smt(unsigned int channel_id, uint32_t *payload_buf) 70 { 71 struct scmi_msg_channel *chan = NULL; 72 struct smt_header *smt_hdr = NULL; 73 size_t in_payload_size = 0; 74 uint32_t smt_status = 0; 75 struct scmi_msg msg = { }; 76 bool error = true; 77 78 chan = plat_scmi_get_channel(channel_id); 79 if (!chan) 80 return; 81 82 smt_hdr = channel_to_smt_hdr(chan); 83 assert(smt_hdr); 84 85 smt_status = READ_ONCE(smt_hdr->status); 86 87 if (!scmi_msg_claim_channel(chan)) { 88 DMSG("SCMI channel %u busy", channel_id); 89 goto out; 90 } 91 92 in_payload_size = READ_ONCE(smt_hdr->length) - 93 sizeof(smt_hdr->message_header); 94 95 if (in_payload_size > SCMI_SEC_PAYLOAD_SIZE) { 96 DMSG("SCMI payload too big %u", in_payload_size); 97 goto out; 98 } 99 100 if (smt_status & (SMT_STATUS_ERROR | SMT_STATUS_FREE)) { 101 DMSG("SCMI channel bad status 0x%x", 102 smt_hdr->status & (SMT_STATUS_ERROR | SMT_STATUS_FREE)); 103 goto out; 104 } 105 106 /* Fill message */ 107 msg.in = (char *)payload_buf; 108 msg.in_size = in_payload_size; 109 msg.out = (char *)smt_hdr->payload; 110 msg.out_size = chan->shm_size - sizeof(*smt_hdr); 111 112 assert(msg.out && msg.out_size >= sizeof(int32_t)); 113 114 /* Here the payload is copied in secure memory */ 115 memcpy(msg.in, smt_hdr->payload, in_payload_size); 116 117 msg.protocol_id = SMT_HDR_PROT_ID(smt_hdr->message_header); 118 msg.message_id = SMT_HDR_MSG_ID(smt_hdr->message_header); 119 msg.channel_id = channel_id; 120 121 scmi_process_message(&msg); 122 123 /* Update message length with the length of the response message */ 124 smt_hdr->length = msg.out_size_out + sizeof(smt_hdr->message_header); 125 126 scmi_msg_release_channel(chan); 127 error = false; 128 129 out: 130 if (error) { 131 DMSG("SCMI error"); 132 smt_hdr->status |= SMT_STATUS_ERROR | SMT_STATUS_FREE; 133 } else { 134 smt_hdr->status |= SMT_STATUS_FREE; 135 } 136 } 137 138 #ifdef CFG_SCMI_MSG_SMT_FASTCALL_ENTRY 139 /* Provision input message payload buffers for fastcall SMC context entries */ 140 static uint32_t fast_smc_payload[CFG_TEE_CORE_NB_CORE][SCMI_PAYLOAD_U32_MAX]; 141 142 void scmi_smt_fastcall_smc_entry(unsigned int channel_id) 143 { 144 scmi_process_smt(channel_id, fast_smc_payload[get_core_pos()]); 145 } 146 #endif 147 148 #ifdef CFG_SCMI_MSG_SMT_INTERRUPT_ENTRY 149 /* Provision input message payload buffers for fastcall SMC context entries */ 150 static uint32_t interrupt_payload[CFG_TEE_CORE_NB_CORE][SCMI_PAYLOAD_U32_MAX]; 151 152 void scmi_smt_interrupt_entry(unsigned int channel_id) 153 { 154 scmi_process_smt(channel_id, interrupt_payload[get_core_pos()]); 155 } 156 #endif 157 158 #ifdef CFG_SCMI_MSG_SMT_THREAD_ENTRY 159 /* Provision input message payload buffers for fastcall SMC context entries */ 160 static uint32_t threaded_payload[CFG_NUM_THREADS][SCMI_PAYLOAD_U32_MAX]; 161 162 void scmi_smt_threaded_entry(unsigned int channel_id) 163 { 164 assert(plat_scmi_get_channel(channel_id)->threaded); 165 166 scmi_process_smt(channel_id, threaded_payload[thread_get_id()]); 167 } 168 #endif 169 170 /* Init a SMT header for a shared memory buffer: state it a free/no-error */ 171 void scmi_smt_init_agent_channel(struct scmi_msg_channel *chan) 172 { 173 static_assert(SCMI_SEC_PAYLOAD_SIZE + sizeof(struct smt_header) <= 174 SMT_BUF_SLOT_SIZE && 175 IS_ALIGNED(SCMI_SEC_PAYLOAD_SIZE, sizeof(uint32_t))); 176 177 if (chan) { 178 struct smt_header *smt_header = channel_to_smt_hdr(chan); 179 180 if (smt_header) { 181 memset(smt_header, 0, sizeof(*smt_header)); 182 smt_header->status = SMT_STATUS_FREE; 183 184 return; 185 } 186 } 187 188 panic(); 189 } 190 191 void scmi_smt_set_shared_buffer(struct scmi_msg_channel *channel, void *base) 192 { 193 paddr_t p_base = 0; 194 195 if (base) { 196 assert(!channel->shm_addr.va && !channel->shm_addr.pa); 197 p_base = virt_to_phys(base); 198 assert(p_base); 199 } 200 201 channel->shm_addr.va = (vaddr_t)base; 202 channel->shm_addr.pa = p_base; 203 } 204