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 31static 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 38u16 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 46static 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 68static 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 */ 97static 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 */ 124static 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 * mc_polling_wait_preemptible() - Waits for the completion of an MC 152 * command doing preemptible polling. 153 * uslepp_range() is called between 154 * polling iterations. 155 * @mc_io: MC I/O object to be used 156 * @cmd: command buffer to receive MC response 157 * @mc_status: MC command completion status 158 */ 159static int mc_polling_wait_preemptible(struct fsl_mc_io *mc_io, 160 struct fsl_mc_command *cmd, 161 enum mc_cmd_status *mc_status) 162{ 163 enum mc_cmd_status status; 164 unsigned long jiffies_until_timeout = 165 jiffies + msecs_to_jiffies(MC_CMD_COMPLETION_TIMEOUT_MS); 166 167 /* 168 * Wait for response from the MC hardware: 169 */ 170 for (;;) { 171 status = mc_read_response(mc_io->portal_virt_addr, cmd); 172 if (status != MC_CMD_STATUS_READY) 173 break; 174 175 /* 176 * TODO: When MC command completion interrupts are supported 177 * call wait function here instead of usleep_range() 178 */ 179 usleep_range(MC_CMD_COMPLETION_POLLING_MIN_SLEEP_USECS, 180 MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS); 181 182 if (time_after_eq(jiffies, jiffies_until_timeout)) { 183 dev_dbg(mc_io->dev, 184 "MC command timed out (portal: %pa, dprc handle: %#x, command: %#x)\n", 185 &mc_io->portal_phys_addr, 186 (unsigned int)mc_cmd_hdr_read_token(cmd), 187 (unsigned int)mc_cmd_hdr_read_cmdid(cmd)); 188 189 return -ETIMEDOUT; 190 } 191 } 192 193 *mc_status = status; 194 return 0; 195} 196 197/** 198 * mc_polling_wait_atomic() - Waits for the completion of an MC command 199 * doing atomic polling. udelay() is called 200 * between polling iterations. 201 * @mc_io: MC I/O object to be used 202 * @cmd: command buffer to receive MC response 203 * @mc_status: MC command completion status 204 */ 205static int mc_polling_wait_atomic(struct fsl_mc_io *mc_io, 206 struct fsl_mc_command *cmd, 207 enum mc_cmd_status *mc_status) 208{ 209 enum mc_cmd_status status; 210 unsigned long timeout_usecs = MC_CMD_COMPLETION_TIMEOUT_MS * 1000; 211 212 BUILD_BUG_ON((MC_CMD_COMPLETION_TIMEOUT_MS * 1000) % 213 MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS != 0); 214 215 for (;;) { 216 status = mc_read_response(mc_io->portal_virt_addr, cmd); 217 if (status != MC_CMD_STATUS_READY) 218 break; 219 220 udelay(MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS); 221 timeout_usecs -= MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS; 222 if (timeout_usecs == 0) { 223 dev_dbg(mc_io->dev, 224 "MC command timed out (portal: %pa, dprc handle: %#x, command: %#x)\n", 225 &mc_io->portal_phys_addr, 226 (unsigned int)mc_cmd_hdr_read_token(cmd), 227 (unsigned int)mc_cmd_hdr_read_cmdid(cmd)); 228 229 return -ETIMEDOUT; 230 } 231 } 232 233 *mc_status = status; 234 return 0; 235} 236 237/** 238 * mc_send_command() - Sends a command to the MC device using the given 239 * MC I/O object 240 * @mc_io: MC I/O object to be used 241 * @cmd: command to be sent 242 * 243 * Returns '0' on Success; Error code otherwise. 244 */ 245int mc_send_command(struct fsl_mc_io *mc_io, struct fsl_mc_command *cmd) 246{ 247 int error; 248 enum mc_cmd_status status; 249 unsigned long irq_flags = 0; 250 251 if (in_irq() && !(mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)) 252 return -EINVAL; 253 254 if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL) 255 raw_spin_lock_irqsave(&mc_io->spinlock, irq_flags); 256 else 257 mutex_lock(&mc_io->mutex); 258 259 /* 260 * Send command to the MC hardware: 261 */ 262 mc_write_command(mc_io->portal_virt_addr, cmd); 263 264 /* 265 * Wait for response from the MC hardware: 266 */ 267 if (!(mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)) 268 error = mc_polling_wait_preemptible(mc_io, cmd, &status); 269 else 270 error = mc_polling_wait_atomic(mc_io, cmd, &status); 271 272 if (error < 0) 273 goto common_exit; 274 275 if (status != MC_CMD_STATUS_OK) { 276 dev_dbg(mc_io->dev, 277 "MC command failed: portal: %pa, dprc handle: %#x, command: %#x, status: %s (%#x)\n", 278 &mc_io->portal_phys_addr, 279 (unsigned int)mc_cmd_hdr_read_token(cmd), 280 (unsigned int)mc_cmd_hdr_read_cmdid(cmd), 281 mc_status_to_string(status), 282 (unsigned int)status); 283 284 error = mc_status_to_error(status); 285 goto common_exit; 286 } 287 288 error = 0; 289common_exit: 290 if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL) 291 raw_spin_unlock_irqrestore(&mc_io->spinlock, irq_flags); 292 else 293 mutex_unlock(&mc_io->mutex); 294 295 return error; 296} 297EXPORT_SYMBOL_GPL(mc_send_command); 298