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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 hardware6 *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 command21 */22#define MC_CMD_COMPLETION_TIMEOUT_MS 50023 24/*25 * usleep_range() min and max values used to throttle down polling26 * iterations while waiting for MC command completion27 */28#define MC_CMD_COMPLETION_POLLING_MIN_SLEEP_USECS 1029#define MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS 50030 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) portal93 *94 * @portal: pointer to an MC portal95 * @cmd: pointer to a filled command96 */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 an106 * extra LE -> CPU conversion so that the CPU -> LE done in107 * 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 a117 * Management Complex (MC) portal118 *119 * @portal: pointer to an MC portal120 * @resp: pointer to command response buffer121 *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 __iomem125 *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 an141 * extra CPU -> LE to revert the LE -> CPU done in142 * 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 MC152 * command doing preemptible polling.153 * uslepp_range() is called between154 * polling iterations.155 * @mc_io: MC I/O object to be used156 * @cmd: command buffer to receive MC response157 * @mc_status: MC command completion status158 */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 supported177 * 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 command199 * doing atomic polling. udelay() is called200 * between polling iterations.201 * @mc_io: MC I/O object to be used202 * @cmd: command buffer to receive MC response203 * @mc_status: MC command completion status204 */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 given239 * MC I/O object240 * @mc_io: MC I/O object to be used241 * @cmd: command to be sent242 *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 else257 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 else270 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 else293 mutex_unlock(&mc_io->mutex);294 295 return error;296}297EXPORT_SYMBOL_GPL(mc_send_command);298