1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2015, Sony Mobile Communications AB. 4 * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved. 5 */ 6 7 #include <linux/module.h> 8 #include <linux/platform_device.h> 9 #include <linux/of_platform.h> 10 #include <linux/io.h> 11 #include <linux/interrupt.h> 12 #include <linux/slab.h> 13 14 #include <linux/rpmsg.h> 15 #include <linux/soc/qcom/smd-rpm.h> 16 17 #define RPM_REQUEST_TIMEOUT (5 * HZ) 18 19 /** 20 * struct qcom_smd_rpm - state of the rpm device driver 21 * @rpm_channel: reference to the smd channel 22 * @icc: interconnect proxy device 23 * @dev: rpm device 24 * @ack: completion for acks 25 * @lock: mutual exclusion around the send/complete pair 26 * @ack_status: result of the rpm request 27 */ 28 struct qcom_smd_rpm { 29 struct rpmsg_endpoint *rpm_channel; 30 struct platform_device *icc; 31 struct device *dev; 32 33 struct completion ack; 34 struct mutex lock; 35 int ack_status; 36 }; 37 38 /** 39 * struct qcom_rpm_header - header for all rpm requests and responses 40 * @service_type: identifier of the service 41 * @length: length of the payload 42 */ 43 struct qcom_rpm_header { 44 __le32 service_type; 45 __le32 length; 46 }; 47 48 /** 49 * struct qcom_rpm_request - request message to the rpm 50 * @msg_id: identifier of the outgoing message 51 * @flags: active/sleep state flags 52 * @type: resource type 53 * @id: resource id 54 * @data_len: length of the payload following this header 55 */ 56 struct qcom_rpm_request { 57 __le32 msg_id; 58 __le32 flags; 59 __le32 type; 60 __le32 id; 61 __le32 data_len; 62 }; 63 64 /** 65 * struct qcom_rpm_message - response message from the rpm 66 * @msg_type: indicator of the type of message 67 * @length: the size of this message, including the message header 68 * @msg_id: message id 69 * @message: textual message from the rpm 70 * 71 * Multiple of these messages can be stacked in an rpm message. 72 */ 73 struct qcom_rpm_message { 74 __le32 msg_type; 75 __le32 length; 76 union { 77 __le32 msg_id; 78 u8 message[0]; 79 }; 80 }; 81 82 #define RPM_SERVICE_TYPE_REQUEST 0x00716572 /* "req\0" */ 83 84 #define RPM_MSG_TYPE_ERR 0x00727265 /* "err\0" */ 85 #define RPM_MSG_TYPE_MSG_ID 0x2367736d /* "msg#" */ 86 87 /** 88 * qcom_rpm_smd_write - write @buf to @type:@id 89 * @rpm: rpm handle 90 * @state: active/sleep state flags 91 * @type: resource type 92 * @id: resource identifier 93 * @buf: the data to be written 94 * @count: number of bytes in @buf 95 */ 96 int qcom_rpm_smd_write(struct qcom_smd_rpm *rpm, 97 int state, 98 u32 type, u32 id, 99 void *buf, 100 size_t count) 101 { 102 static unsigned msg_id = 1; 103 int left; 104 int ret; 105 struct { 106 struct qcom_rpm_header hdr; 107 struct qcom_rpm_request req; 108 u8 payload[]; 109 } *pkt; 110 size_t size = sizeof(*pkt) + count; 111 112 /* SMD packets to the RPM may not exceed 256 bytes */ 113 if (WARN_ON(size >= 256)) 114 return -EINVAL; 115 116 pkt = kmalloc(size, GFP_KERNEL); 117 if (!pkt) 118 return -ENOMEM; 119 120 mutex_lock(&rpm->lock); 121 122 pkt->hdr.service_type = cpu_to_le32(RPM_SERVICE_TYPE_REQUEST); 123 pkt->hdr.length = cpu_to_le32(sizeof(struct qcom_rpm_request) + count); 124 125 pkt->req.msg_id = cpu_to_le32(msg_id++); 126 pkt->req.flags = cpu_to_le32(state); 127 pkt->req.type = cpu_to_le32(type); 128 pkt->req.id = cpu_to_le32(id); 129 pkt->req.data_len = cpu_to_le32(count); 130 memcpy(pkt->payload, buf, count); 131 132 ret = rpmsg_send(rpm->rpm_channel, pkt, size); 133 if (ret) 134 goto out; 135 136 left = wait_for_completion_timeout(&rpm->ack, RPM_REQUEST_TIMEOUT); 137 if (!left) 138 ret = -ETIMEDOUT; 139 else 140 ret = rpm->ack_status; 141 142 out: 143 kfree(pkt); 144 mutex_unlock(&rpm->lock); 145 return ret; 146 } 147 EXPORT_SYMBOL(qcom_rpm_smd_write); 148 149 static int qcom_smd_rpm_callback(struct rpmsg_device *rpdev, 150 void *data, 151 int count, 152 void *priv, 153 u32 addr) 154 { 155 const struct qcom_rpm_header *hdr = data; 156 size_t hdr_length = le32_to_cpu(hdr->length); 157 const struct qcom_rpm_message *msg; 158 struct qcom_smd_rpm *rpm = dev_get_drvdata(&rpdev->dev); 159 const u8 *buf = data + sizeof(struct qcom_rpm_header); 160 const u8 *end = buf + hdr_length; 161 char msgbuf[32]; 162 int status = 0; 163 u32 len, msg_length; 164 165 if (le32_to_cpu(hdr->service_type) != RPM_SERVICE_TYPE_REQUEST || 166 hdr_length < sizeof(struct qcom_rpm_message)) { 167 dev_err(rpm->dev, "invalid request\n"); 168 return 0; 169 } 170 171 while (buf < end) { 172 msg = (struct qcom_rpm_message *)buf; 173 msg_length = le32_to_cpu(msg->length); 174 switch (le32_to_cpu(msg->msg_type)) { 175 case RPM_MSG_TYPE_MSG_ID: 176 break; 177 case RPM_MSG_TYPE_ERR: 178 len = min_t(u32, ALIGN(msg_length, 4), sizeof(msgbuf)); 179 memcpy_fromio(msgbuf, msg->message, len); 180 msgbuf[len - 1] = 0; 181 182 if (!strcmp(msgbuf, "resource does not exist")) 183 status = -ENXIO; 184 else 185 status = -EINVAL; 186 break; 187 } 188 189 buf = PTR_ALIGN(buf + 2 * sizeof(u32) + msg_length, 4); 190 } 191 192 rpm->ack_status = status; 193 complete(&rpm->ack); 194 return 0; 195 } 196 197 static int qcom_smd_rpm_probe(struct rpmsg_device *rpdev) 198 { 199 struct qcom_smd_rpm *rpm; 200 int ret; 201 202 rpm = devm_kzalloc(&rpdev->dev, sizeof(*rpm), GFP_KERNEL); 203 if (!rpm) 204 return -ENOMEM; 205 206 mutex_init(&rpm->lock); 207 init_completion(&rpm->ack); 208 209 rpm->dev = &rpdev->dev; 210 rpm->rpm_channel = rpdev->ept; 211 dev_set_drvdata(&rpdev->dev, rpm); 212 213 rpm->icc = platform_device_register_data(&rpdev->dev, "icc_smd_rpm", -1, 214 NULL, 0); 215 if (IS_ERR(rpm->icc)) 216 return PTR_ERR(rpm->icc); 217 218 ret = of_platform_populate(rpdev->dev.of_node, NULL, NULL, &rpdev->dev); 219 if (ret) 220 platform_device_unregister(rpm->icc); 221 222 return ret; 223 } 224 225 static void qcom_smd_rpm_remove(struct rpmsg_device *rpdev) 226 { 227 struct qcom_smd_rpm *rpm = dev_get_drvdata(&rpdev->dev); 228 229 platform_device_unregister(rpm->icc); 230 of_platform_depopulate(&rpdev->dev); 231 } 232 233 static const struct of_device_id qcom_smd_rpm_of_match[] = { 234 { .compatible = "qcom,rpm-apq8084" }, 235 { .compatible = "qcom,rpm-ipq6018" }, 236 { .compatible = "qcom,rpm-msm8916" }, 237 { .compatible = "qcom,rpm-msm8936" }, 238 { .compatible = "qcom,rpm-msm8974" }, 239 { .compatible = "qcom,rpm-msm8976" }, 240 { .compatible = "qcom,rpm-msm8994" }, 241 { .compatible = "qcom,rpm-msm8996" }, 242 { .compatible = "qcom,rpm-msm8998" }, 243 { .compatible = "qcom,rpm-sdm660" }, 244 { .compatible = "qcom,rpm-qcs404" }, 245 {} 246 }; 247 MODULE_DEVICE_TABLE(of, qcom_smd_rpm_of_match); 248 249 static struct rpmsg_driver qcom_smd_rpm_driver = { 250 .probe = qcom_smd_rpm_probe, 251 .remove = qcom_smd_rpm_remove, 252 .callback = qcom_smd_rpm_callback, 253 .drv = { 254 .name = "qcom_smd_rpm", 255 .of_match_table = qcom_smd_rpm_of_match, 256 }, 257 }; 258 259 static int __init qcom_smd_rpm_init(void) 260 { 261 return register_rpmsg_driver(&qcom_smd_rpm_driver); 262 } 263 arch_initcall(qcom_smd_rpm_init); 264 265 static void __exit qcom_smd_rpm_exit(void) 266 { 267 unregister_rpmsg_driver(&qcom_smd_rpm_driver); 268 } 269 module_exit(qcom_smd_rpm_exit); 270 271 MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@sonymobile.com>"); 272 MODULE_DESCRIPTION("Qualcomm SMD backed RPM driver"); 273 MODULE_LICENSE("GPL v2"); 274