1 // SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause) 2 /* 3 * Copyright 2013-2016 Freescale Semiconductor Inc. 4 * 5 * I/O services to send MC commands to the MC hardware 6 * 7 */ 8 9 #include <linux/delay.h> 10 #include <linux/slab.h> 11 #include <linux/ioport.h> 12 #include <linux/device.h> 13 #include <linux/io.h> 14 #include <linux/io-64-nonatomic-hi-lo.h> 15 #include <linux/fsl/mc.h> 16 17 #include "fsl-mc-private.h" 18 19 /** 20 * Timeout in milliseconds to wait for the completion of an MC command 21 */ 22 #define MC_CMD_COMPLETION_TIMEOUT_MS 500 23 24 /* 25 * usleep_range() min and max values used to throttle down polling 26 * iterations while waiting for MC command completion 27 */ 28 #define MC_CMD_COMPLETION_POLLING_MIN_SLEEP_USECS 10 29 #define MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS 500 30 31 static enum mc_cmd_status mc_cmd_hdr_read_status(struct fsl_mc_command *cmd) 32 { 33 struct mc_cmd_header *hdr = (struct mc_cmd_header *)&cmd->header; 34 35 return (enum mc_cmd_status)hdr->status; 36 } 37 38 static u16 mc_cmd_hdr_read_cmdid(struct fsl_mc_command *cmd) 39 { 40 struct mc_cmd_header *hdr = (struct mc_cmd_header *)&cmd->header; 41 u16 cmd_id = le16_to_cpu(hdr->cmd_id); 42 43 return cmd_id; 44 } 45 46 static int mc_status_to_error(enum mc_cmd_status status) 47 { 48 static const int mc_status_to_error_map[] = { 49 [MC_CMD_STATUS_OK] = 0, 50 [MC_CMD_STATUS_AUTH_ERR] = -EACCES, 51 [MC_CMD_STATUS_NO_PRIVILEGE] = -EPERM, 52 [MC_CMD_STATUS_DMA_ERR] = -EIO, 53 [MC_CMD_STATUS_CONFIG_ERR] = -ENXIO, 54 [MC_CMD_STATUS_TIMEOUT] = -ETIMEDOUT, 55 [MC_CMD_STATUS_NO_RESOURCE] = -ENAVAIL, 56 [MC_CMD_STATUS_NO_MEMORY] = -ENOMEM, 57 [MC_CMD_STATUS_BUSY] = -EBUSY, 58 [MC_CMD_STATUS_UNSUPPORTED_OP] = -ENOTSUPP, 59 [MC_CMD_STATUS_INVALID_STATE] = -ENODEV, 60 }; 61 62 if ((u32)status >= ARRAY_SIZE(mc_status_to_error_map)) 63 return -EINVAL; 64 65 return mc_status_to_error_map[status]; 66 } 67 68 static const char *mc_status_to_string(enum mc_cmd_status status) 69 { 70 static const char *const status_strings[] = { 71 [MC_CMD_STATUS_OK] = "Command completed successfully", 72 [MC_CMD_STATUS_READY] = "Command ready to be processed", 73 [MC_CMD_STATUS_AUTH_ERR] = "Authentication error", 74 [MC_CMD_STATUS_NO_PRIVILEGE] = "No privilege", 75 [MC_CMD_STATUS_DMA_ERR] = "DMA or I/O error", 76 [MC_CMD_STATUS_CONFIG_ERR] = "Configuration error", 77 [MC_CMD_STATUS_TIMEOUT] = "Operation timed out", 78 [MC_CMD_STATUS_NO_RESOURCE] = "No resources", 79 [MC_CMD_STATUS_NO_MEMORY] = "No memory available", 80 [MC_CMD_STATUS_BUSY] = "Device is busy", 81 [MC_CMD_STATUS_UNSUPPORTED_OP] = "Unsupported operation", 82 [MC_CMD_STATUS_INVALID_STATE] = "Invalid state" 83 }; 84 85 if ((unsigned int)status >= ARRAY_SIZE(status_strings)) 86 return "Unknown MC error"; 87 88 return status_strings[status]; 89 } 90 91 /** 92 * mc_write_command - writes a command to a Management Complex (MC) portal 93 * 94 * @portal: pointer to an MC portal 95 * @cmd: pointer to a filled command 96 */ 97 static inline void mc_write_command(struct fsl_mc_command __iomem *portal, 98 struct fsl_mc_command *cmd) 99 { 100 int i; 101 102 /* copy command parameters into the portal */ 103 for (i = 0; i < MC_CMD_NUM_OF_PARAMS; i++) 104 /* 105 * Data is already in the expected LE byte-order. Do an 106 * extra LE -> CPU conversion so that the CPU -> LE done in 107 * the device io write api puts it back in the right order. 108 */ 109 writeq_relaxed(le64_to_cpu(cmd->params[i]), &portal->params[i]); 110 111 /* submit the command by writing the header */ 112 writeq(le64_to_cpu(cmd->header), &portal->header); 113 } 114 115 /** 116 * mc_read_response - reads the response for the last MC command from a 117 * Management Complex (MC) portal 118 * 119 * @portal: pointer to an MC portal 120 * @resp: pointer to command response buffer 121 * 122 * Returns MC_CMD_STATUS_OK on Success; Error code otherwise. 123 */ 124 static inline enum mc_cmd_status mc_read_response(struct fsl_mc_command __iomem 125 *portal, 126 struct fsl_mc_command *resp) 127 { 128 int i; 129 enum mc_cmd_status status; 130 131 /* Copy command response header from MC portal: */ 132 resp->header = cpu_to_le64(readq_relaxed(&portal->header)); 133 status = mc_cmd_hdr_read_status(resp); 134 if (status != MC_CMD_STATUS_OK) 135 return status; 136 137 /* Copy command response data from MC portal: */ 138 for (i = 0; i < MC_CMD_NUM_OF_PARAMS; i++) 139 /* 140 * Data is expected to be in LE byte-order. Do an 141 * extra CPU -> LE to revert the LE -> CPU done in 142 * the device io read api. 143 */ 144 resp->params[i] = 145 cpu_to_le64(readq_relaxed(&portal->params[i])); 146 147 return status; 148 } 149 150 /** 151 * Waits for the completion of an MC command doing preemptible polling. 152 * uslepp_range() is called between polling iterations. 153 * 154 * @mc_io: MC I/O object to be used 155 * @cmd: command buffer to receive MC response 156 * @mc_status: MC command completion status 157 */ 158 static int mc_polling_wait_preemptible(struct fsl_mc_io *mc_io, 159 struct fsl_mc_command *cmd, 160 enum mc_cmd_status *mc_status) 161 { 162 enum mc_cmd_status status; 163 unsigned long jiffies_until_timeout = 164 jiffies + msecs_to_jiffies(MC_CMD_COMPLETION_TIMEOUT_MS); 165 166 /* 167 * Wait for response from the MC hardware: 168 */ 169 for (;;) { 170 status = mc_read_response(mc_io->portal_virt_addr, cmd); 171 if (status != MC_CMD_STATUS_READY) 172 break; 173 174 /* 175 * TODO: When MC command completion interrupts are supported 176 * call wait function here instead of usleep_range() 177 */ 178 usleep_range(MC_CMD_COMPLETION_POLLING_MIN_SLEEP_USECS, 179 MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS); 180 181 if (time_after_eq(jiffies, jiffies_until_timeout)) { 182 dev_dbg(mc_io->dev, 183 "MC command timed out (portal: %pa, dprc handle: %#x, command: %#x)\n", 184 &mc_io->portal_phys_addr, 185 (unsigned int)mc_cmd_hdr_read_token(cmd), 186 (unsigned int)mc_cmd_hdr_read_cmdid(cmd)); 187 188 return -ETIMEDOUT; 189 } 190 } 191 192 *mc_status = status; 193 return 0; 194 } 195 196 /** 197 * Waits for the completion of an MC command doing atomic polling. 198 * udelay() is called between polling iterations. 199 * 200 * @mc_io: MC I/O object to be used 201 * @cmd: command buffer to receive MC response 202 * @mc_status: MC command completion status 203 */ 204 static int mc_polling_wait_atomic(struct fsl_mc_io *mc_io, 205 struct fsl_mc_command *cmd, 206 enum mc_cmd_status *mc_status) 207 { 208 enum mc_cmd_status status; 209 unsigned long timeout_usecs = MC_CMD_COMPLETION_TIMEOUT_MS * 1000; 210 211 BUILD_BUG_ON((MC_CMD_COMPLETION_TIMEOUT_MS * 1000) % 212 MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS != 0); 213 214 for (;;) { 215 status = mc_read_response(mc_io->portal_virt_addr, cmd); 216 if (status != MC_CMD_STATUS_READY) 217 break; 218 219 udelay(MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS); 220 timeout_usecs -= MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS; 221 if (timeout_usecs == 0) { 222 dev_dbg(mc_io->dev, 223 "MC command timed out (portal: %pa, dprc handle: %#x, command: %#x)\n", 224 &mc_io->portal_phys_addr, 225 (unsigned int)mc_cmd_hdr_read_token(cmd), 226 (unsigned int)mc_cmd_hdr_read_cmdid(cmd)); 227 228 return -ETIMEDOUT; 229 } 230 } 231 232 *mc_status = status; 233 return 0; 234 } 235 236 /** 237 * Sends a command to the MC device using the given MC I/O object 238 * 239 * @mc_io: MC I/O object to be used 240 * @cmd: command to be sent 241 * 242 * Returns '0' on Success; Error code otherwise. 243 */ 244 int mc_send_command(struct fsl_mc_io *mc_io, struct fsl_mc_command *cmd) 245 { 246 int error; 247 enum mc_cmd_status status; 248 unsigned long irq_flags = 0; 249 250 if (in_irq() && !(mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)) 251 return -EINVAL; 252 253 if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL) 254 raw_spin_lock_irqsave(&mc_io->spinlock, irq_flags); 255 else 256 mutex_lock(&mc_io->mutex); 257 258 /* 259 * Send command to the MC hardware: 260 */ 261 mc_write_command(mc_io->portal_virt_addr, cmd); 262 263 /* 264 * Wait for response from the MC hardware: 265 */ 266 if (!(mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)) 267 error = mc_polling_wait_preemptible(mc_io, cmd, &status); 268 else 269 error = mc_polling_wait_atomic(mc_io, cmd, &status); 270 271 if (error < 0) 272 goto common_exit; 273 274 if (status != MC_CMD_STATUS_OK) { 275 dev_dbg(mc_io->dev, 276 "MC command failed: portal: %pa, dprc handle: %#x, command: %#x, status: %s (%#x)\n", 277 &mc_io->portal_phys_addr, 278 (unsigned int)mc_cmd_hdr_read_token(cmd), 279 (unsigned int)mc_cmd_hdr_read_cmdid(cmd), 280 mc_status_to_string(status), 281 (unsigned int)status); 282 283 error = mc_status_to_error(status); 284 goto common_exit; 285 } 286 287 error = 0; 288 common_exit: 289 if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL) 290 raw_spin_unlock_irqrestore(&mc_io->spinlock, irq_flags); 291 else 292 mutex_unlock(&mc_io->mutex); 293 294 return error; 295 } 296 EXPORT_SYMBOL_GPL(mc_send_command); 297