1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Platform driver for CDX bus. 4 * 5 * Copyright (C) 2022-2023, Advanced Micro Devices, Inc. 6 */ 7 8 #include <linux/rpmsg.h> 9 #include <linux/remoteproc.h> 10 #include <linux/of.h> 11 #include <linux/platform_device.h> 12 #include <linux/cdx/cdx_bus.h> 13 #include <linux/module.h> 14 15 #include "../cdx.h" 16 #include "cdx_controller.h" 17 #include "mcdi_functions.h" 18 #include "mcdi.h" 19 20 static struct rpmsg_device_id cdx_rpmsg_id_table[] = { 21 { .name = "mcdi_ipc" }, 22 { }, 23 }; 24 MODULE_DEVICE_TABLE(rpmsg, cdx_rpmsg_id_table); 25 26 int cdx_rpmsg_send(struct cdx_mcdi *cdx_mcdi, 27 const struct cdx_dword *hdr, size_t hdr_len, 28 const struct cdx_dword *sdu, size_t sdu_len) 29 { 30 unsigned char *send_buf; 31 int ret; 32 33 send_buf = kzalloc(hdr_len + sdu_len, GFP_KERNEL); 34 if (!send_buf) 35 return -ENOMEM; 36 37 memcpy(send_buf, hdr, hdr_len); 38 memcpy(send_buf + hdr_len, sdu, sdu_len); 39 40 ret = rpmsg_send(cdx_mcdi->ept, send_buf, hdr_len + sdu_len); 41 kfree(send_buf); 42 43 return ret; 44 } 45 46 static int cdx_attach_to_rproc(struct platform_device *pdev) 47 { 48 struct device_node *r5_core_node; 49 struct cdx_controller *cdx_c; 50 struct cdx_mcdi *cdx_mcdi; 51 struct device *dev; 52 struct rproc *rp; 53 int ret; 54 55 dev = &pdev->dev; 56 cdx_c = platform_get_drvdata(pdev); 57 cdx_mcdi = cdx_c->priv; 58 59 r5_core_node = of_parse_phandle(dev->of_node, "xlnx,rproc", 0); 60 if (!r5_core_node) { 61 dev_err(&pdev->dev, "xlnx,rproc: invalid phandle\n"); 62 return -EINVAL; 63 } 64 65 rp = rproc_get_by_phandle(r5_core_node->phandle); 66 if (!rp) { 67 ret = -EPROBE_DEFER; 68 goto pdev_err; 69 } 70 71 /* Attach to remote processor */ 72 ret = rproc_boot(rp); 73 if (ret) { 74 dev_err(&pdev->dev, "Failed to attach to remote processor\n"); 75 rproc_put(rp); 76 goto pdev_err; 77 } 78 79 cdx_mcdi->r5_rproc = rp; 80 pdev_err: 81 of_node_put(r5_core_node); 82 return ret; 83 } 84 85 static void cdx_detach_to_r5(struct platform_device *pdev) 86 { 87 struct cdx_controller *cdx_c; 88 struct cdx_mcdi *cdx_mcdi; 89 90 cdx_c = platform_get_drvdata(pdev); 91 cdx_mcdi = cdx_c->priv; 92 93 rproc_detach(cdx_mcdi->r5_rproc); 94 rproc_put(cdx_mcdi->r5_rproc); 95 } 96 97 static int cdx_rpmsg_cb(struct rpmsg_device *rpdev, void *data, 98 int len, void *priv, u32 src) 99 { 100 struct cdx_controller *cdx_c = dev_get_drvdata(&rpdev->dev); 101 struct cdx_mcdi *cdx_mcdi = cdx_c->priv; 102 103 if (len > MCDI_BUF_LEN) 104 return -EINVAL; 105 106 cdx_mcdi_process_cmd(cdx_mcdi, (struct cdx_dword *)data, len); 107 108 return 0; 109 } 110 111 static void cdx_rpmsg_post_probe_work(struct work_struct *work) 112 { 113 struct cdx_controller *cdx_c; 114 struct cdx_mcdi *cdx_mcdi; 115 116 cdx_mcdi = container_of(work, struct cdx_mcdi, work); 117 cdx_c = dev_get_drvdata(&cdx_mcdi->rpdev->dev); 118 cdx_rpmsg_post_probe(cdx_c); 119 } 120 121 static int cdx_rpmsg_probe(struct rpmsg_device *rpdev) 122 { 123 struct rpmsg_channel_info chinfo = {0}; 124 struct cdx_controller *cdx_c; 125 struct cdx_mcdi *cdx_mcdi; 126 127 cdx_c = (struct cdx_controller *)cdx_rpmsg_id_table[0].driver_data; 128 cdx_mcdi = cdx_c->priv; 129 130 chinfo.src = RPMSG_ADDR_ANY; 131 chinfo.dst = rpdev->dst; 132 strscpy(chinfo.name, cdx_rpmsg_id_table[0].name, 133 strlen(cdx_rpmsg_id_table[0].name)); 134 135 cdx_mcdi->ept = rpmsg_create_ept(rpdev, cdx_rpmsg_cb, NULL, chinfo); 136 if (!cdx_mcdi->ept) { 137 dev_err_probe(&rpdev->dev, -ENXIO, 138 "Failed to create ept for channel %s\n", 139 chinfo.name); 140 return -EINVAL; 141 } 142 143 cdx_mcdi->rpdev = rpdev; 144 dev_set_drvdata(&rpdev->dev, cdx_c); 145 146 schedule_work(&cdx_mcdi->work); 147 return 0; 148 } 149 150 static void cdx_rpmsg_remove(struct rpmsg_device *rpdev) 151 { 152 struct cdx_controller *cdx_c = dev_get_drvdata(&rpdev->dev); 153 struct cdx_mcdi *cdx_mcdi = cdx_c->priv; 154 155 flush_work(&cdx_mcdi->work); 156 cdx_rpmsg_pre_remove(cdx_c); 157 158 rpmsg_destroy_ept(cdx_mcdi->ept); 159 dev_set_drvdata(&rpdev->dev, NULL); 160 } 161 162 static struct rpmsg_driver cdx_rpmsg_driver = { 163 .drv.name = KBUILD_MODNAME, 164 .id_table = cdx_rpmsg_id_table, 165 .probe = cdx_rpmsg_probe, 166 .remove = cdx_rpmsg_remove, 167 .callback = cdx_rpmsg_cb, 168 }; 169 170 int cdx_setup_rpmsg(struct platform_device *pdev) 171 { 172 struct cdx_controller *cdx_c; 173 struct cdx_mcdi *cdx_mcdi; 174 int ret; 175 176 /* Attach to remote processor */ 177 ret = cdx_attach_to_rproc(pdev); 178 if (ret) 179 return ret; 180 181 cdx_c = platform_get_drvdata(pdev); 182 cdx_mcdi = cdx_c->priv; 183 184 /* Register RPMsg driver */ 185 cdx_rpmsg_id_table[0].driver_data = (kernel_ulong_t)cdx_c; 186 187 INIT_WORK(&cdx_mcdi->work, cdx_rpmsg_post_probe_work); 188 ret = register_rpmsg_driver(&cdx_rpmsg_driver); 189 if (ret) { 190 dev_err(&pdev->dev, 191 "Failed to register cdx RPMsg driver: %d\n", ret); 192 cdx_detach_to_r5(pdev); 193 } 194 195 return ret; 196 } 197 198 void cdx_destroy_rpmsg(struct platform_device *pdev) 199 { 200 unregister_rpmsg_driver(&cdx_rpmsg_driver); 201 202 cdx_detach_to_r5(pdev); 203 } 204