kernel/drivers/staging/fsl-mc/bus/mc-sys.c

   1 /* Copyright 2013-2014 Freescale Semiconductor Inc.
   2  *
   3  * I/O services to send MC commands to the MC hardware
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are met:
   7  *     * Redistributions of source code must retain the above copyright
   8  *       notice, this list of conditions and the following disclaimer.
   9  *     * Redistributions in binary form must reproduce the above copyright
  10  *       notice, this list of conditions and the following disclaimer in the
  11  *       documentation and/or other materials provided with the distribution.
  12  *     * Neither the name of the above-listed copyright holders nor the
  13  *       names of any contributors may be used to endorse or promote products
  14  *       derived from this software without specific prior written permission.
  15  *
  16  *
  17  * ALTERNATIVELY, this software may be distributed under the terms of the
  18  * GNU General Public License ("GPL") as published by the Free Software
  19  * Foundation, either version 2 of that License or (at your option) any
  20  * later version.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  23  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
  26  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  32  * POSSIBILITY OF SUCH DAMAGE.
  33  */
  34
  35 #include "../include/mc-sys.h"
  36 #include "../include/mc-cmd.h"
  37 #include <linux/delay.h>
  38 #include <linux/slab.h>
  39 #include <linux/ioport.h>
  40 #include <linux/device.h>
  41
  42 /**
  43  * Timeout in jiffies to wait for the completion of an MC command
  44  */
  45 #define MC_CMD_COMPLETION_TIMEOUT_JIFFIES   (HZ / 2)    /* 500 ms */
  46
  47 /*
  48  * usleep_range() min and max values used to throttle down polling
  49  * iterations while waiting for MC command completion
  50  */
  51 #define MC_CMD_COMPLETION_POLLING_MIN_SLEEP_USECS    10
  52 #define MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS    500
  53
  54 #define MC_CMD_HDR_READ_CMDID(_hdr) \
  55         ((uint16_t)mc_dec((_hdr), MC_CMD_HDR_CMDID_O, MC_CMD_HDR_CMDID_S))
  56
  57 /**
  58  * Creates an MC I/O object
  59  *
  60  * @dev: device to be associated with the MC I/O object
  61  * @mc_portal_phys_addr: physical address of the MC portal to use
  62  * @mc_portal_size: size in bytes of the MC portal
  63  * @resource: Pointer to MC bus object allocator resource associated
  64  * with this MC I/O object or NULL if none.
  65  * @flags: flags for the new MC I/O object
  66  * @new_mc_io: Area to return pointer to newly created MC I/O object
  67  *
  68  * Returns '0' on Success; Error code otherwise.
  69  */
  70 int __must_check fsl_create_mc_io(struct device *dev,
  71                                   phys_addr_t mc_portal_phys_addr,
  72                                   uint32_t mc_portal_size,
  73                                   struct fsl_mc_resource *resource,
  74                                   uint32_t flags, struct fsl_mc_io **new_mc_io)
  75 {
  76         struct fsl_mc_io *mc_io;
  77         void __iomem *mc_portal_virt_addr;
  78         struct resource *res;
  79
  80         mc_io = devm_kzalloc(dev, sizeof(*mc_io), GFP_KERNEL);
  81         if (!mc_io)
  82                 return -ENOMEM;
  83
  84         mc_io->dev = dev;
  85         mc_io->flags = flags;
  86         mc_io->portal_phys_addr = mc_portal_phys_addr;
  87         mc_io->portal_size = mc_portal_size;
  88         mc_io->resource = resource;
  89         res = devm_request_mem_region(dev,
  90                                       mc_portal_phys_addr,
  91                                       mc_portal_size,
  92                                       "mc_portal");
  93         if (!res) {
  94                 dev_err(dev,
  95                         "devm_request_mem_region failed for MC portal %#llx\n",
  96                         mc_portal_phys_addr);
  97                 return -EBUSY;
  98         }
  99
 100         mc_portal_virt_addr = devm_ioremap_nocache(dev,
 101                                                    mc_portal_phys_addr,
 102                                                    mc_portal_size);
 103         if (!mc_portal_virt_addr) {
 104                 dev_err(dev,
 105                         "devm_ioremap_nocache failed for MC portal %#llx\n",
 106                         mc_portal_phys_addr);
 107                 return -ENXIO;
 108         }
 109
 110         mc_io->portal_virt_addr = mc_portal_virt_addr;
 111         *new_mc_io = mc_io;
 112         return 0;
 113 }
 114 EXPORT_SYMBOL_GPL(fsl_create_mc_io);
 115
 116 /**
 117  * Destroys an MC I/O object
 118  *
 119  * @mc_io: MC I/O object to destroy
 120  */
 121 void fsl_destroy_mc_io(struct fsl_mc_io *mc_io)
 122 {
 123         devm_iounmap(mc_io->dev, mc_io->portal_virt_addr);
 124         devm_release_mem_region(mc_io->dev,
 125                                 mc_io->portal_phys_addr,
 126                                 mc_io->portal_size);
 127
 128         mc_io->portal_virt_addr = NULL;
 129         devm_kfree(mc_io->dev, mc_io);
 130 }
 131 EXPORT_SYMBOL_GPL(fsl_destroy_mc_io);
 132
 133 static int mc_status_to_error(enum mc_cmd_status status)
 134 {
 135         static const int mc_status_to_error_map[] = {
 136                 [MC_CMD_STATUS_OK] = 0,
 137                 [MC_CMD_STATUS_AUTH_ERR] = -EACCES,
 138                 [MC_CMD_STATUS_NO_PRIVILEGE] = -EPERM,
 139                 [MC_CMD_STATUS_DMA_ERR] = -EIO,
 140                 [MC_CMD_STATUS_CONFIG_ERR] = -ENXIO,
 141                 [MC_CMD_STATUS_TIMEOUT] = -ETIMEDOUT,
 142                 [MC_CMD_STATUS_NO_RESOURCE] = -ENAVAIL,
 143                 [MC_CMD_STATUS_NO_MEMORY] = -ENOMEM,
 144                 [MC_CMD_STATUS_BUSY] = -EBUSY,
 145                 [MC_CMD_STATUS_UNSUPPORTED_OP] = -ENOTSUPP,
 146                 [MC_CMD_STATUS_INVALID_STATE] = -ENODEV,
 147         };
 148
 149         if (WARN_ON((u32)status >= ARRAY_SIZE(mc_status_to_error_map)))
 150                 return -EINVAL;
 151
 152         return mc_status_to_error_map[status];
 153 }
 154
 155 static const char *mc_status_to_string(enum mc_cmd_status status)
 156 {
 157         static const char *const status_strings[] = {
 158                 [MC_CMD_STATUS_OK] = "Command completed successfully",
 159                 [MC_CMD_STATUS_READY] = "Command ready to be processed",
 160                 [MC_CMD_STATUS_AUTH_ERR] = "Authentication error",
 161                 [MC_CMD_STATUS_NO_PRIVILEGE] = "No privilege",
 162                 [MC_CMD_STATUS_DMA_ERR] = "DMA or I/O error",
 163                 [MC_CMD_STATUS_CONFIG_ERR] = "Configuration error",
 164                 [MC_CMD_STATUS_TIMEOUT] = "Operation timed out",
 165                 [MC_CMD_STATUS_NO_RESOURCE] = "No resources",
 166                 [MC_CMD_STATUS_NO_MEMORY] = "No memory available",
 167                 [MC_CMD_STATUS_BUSY] = "Device is busy",
 168                 [MC_CMD_STATUS_UNSUPPORTED_OP] = "Unsupported operation",
 169                 [MC_CMD_STATUS_INVALID_STATE] = "Invalid state"
 170         };
 171
 172         if ((unsigned int)status >= ARRAY_SIZE(status_strings))
 173                 return "Unknown MC error";
 174
 175         return status_strings[status];
 176 }
 177
 178 /**
 179  * mc_write_command - writes a command to a Management Complex (MC) portal
 180  *
 181  * @portal: pointer to an MC portal
 182  * @cmd: pointer to a filled command
 183  */
 184 static inline void mc_write_command(struct mc_command __iomem *portal,
 185                                     struct mc_command *cmd)
 186 {
 187         int i;
 188
 189         /* copy command parameters into the portal */
 190         for (i = 0; i < MC_CMD_NUM_OF_PARAMS; i++)
 191                 writeq(cmd->params[i], &portal->params[i]);
 192
 193         /* submit the command by writing the header */
 194         writeq(cmd->header, &portal->header);
 195 }
 196
 197 /**
 198  * mc_read_response - reads the response for the last MC command from a
 199  * Management Complex (MC) portal
 200  *
 201  * @portal: pointer to an MC portal
 202  * @resp: pointer to command response buffer
 203  *
 204  * Returns MC_CMD_STATUS_OK on Success; Error code otherwise.
 205  */
 206 static inline enum mc_cmd_status mc_read_response(struct mc_command __iomem *
 207                                                   portal,
 208                                                   struct mc_command *resp)
 209 {
 210         int i;
 211         enum mc_cmd_status status;
 212
 213         /* Copy command response header from MC portal: */
 214         resp->header = readq(&portal->header);
 215         status = MC_CMD_HDR_READ_STATUS(resp->header);
 216         if (status != MC_CMD_STATUS_OK)
 217                 return status;
 218
 219         /* Copy command response data from MC portal: */
 220         for (i = 0; i < MC_CMD_NUM_OF_PARAMS; i++)
 221                 resp->params[i] = readq(&portal->params[i]);
 222
 223         return status;
 224 }
 225
 226 /**
 227  * Sends an command to the MC device using the given MC I/O object
 228  *
 229  * @mc_io: MC I/O object to be used
 230  * @cmd: command to be sent
 231  *
 232  * Returns '0' on Success; Error code otherwise.
 233  *
 234  * NOTE: This function cannot be invoked from from atomic contexts.
 235  */
 236 int mc_send_command(struct fsl_mc_io *mc_io, struct mc_command *cmd)
 237 {
 238         enum mc_cmd_status status;
 239         unsigned long jiffies_until_timeout =
 240             jiffies + MC_CMD_COMPLETION_TIMEOUT_JIFFIES;
 241
 242         /*
 243          * Send command to the MC hardware:
 244          */
 245         mc_write_command(mc_io->portal_virt_addr, cmd);
 246
 247         /*
 248          * Wait for response from the MC hardware:
 249          */
 250         for (;;) {
 251                 status = mc_read_response(mc_io->portal_virt_addr, cmd);
 252                 if (status != MC_CMD_STATUS_READY)
 253                         break;
 254
 255                 /*
 256                  * TODO: When MC command completion interrupts are supported
 257                  * call wait function here instead of usleep_range()
 258                  */
 259                 usleep_range(MC_CMD_COMPLETION_POLLING_MIN_SLEEP_USECS,
 260                              MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS);
 261
 262                 if (time_after_eq(jiffies, jiffies_until_timeout)) {
 263                         pr_debug("MC command timed out (portal: %#llx, obj handle: %#x, command: %#x)\n",
 264                                  mc_io->portal_phys_addr,
 265                                  (unsigned int)
 266                                         MC_CMD_HDR_READ_TOKEN(cmd->header),
 267                                  (unsigned int)
 268                                         MC_CMD_HDR_READ_CMDID(cmd->header));
 269
 270                         return -ETIMEDOUT;
 271                 }
 272         }
 273
 274         if (status != MC_CMD_STATUS_OK) {
 275                 pr_debug("MC command failed: portal: %#llx, obj handle: %#x, command: %#x, status: %s (%#x)\n",
 276                          mc_io->portal_phys_addr,
 277                          (unsigned int)MC_CMD_HDR_READ_TOKEN(cmd->header),
 278                          (unsigned int)MC_CMD_HDR_READ_CMDID(cmd->header),
 279                          mc_status_to_string(status),
 280                          (unsigned int)status);
 281
 282                 return mc_status_to_error(status);
 283         }
 284
 285         return 0;
 286 }
 287 EXPORT_SYMBOL(mc_send_command);