drivers/soc/fsl/dpaa2-console.c

   1 // SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
   2 /*
   3  * Freescale DPAA2 Platforms Console Driver
   4  *
   5  * Copyright 2015-2016 Freescale Semiconductor Inc.
   6  * Copyright 2018 NXP
   7  */
   8
   9 #define pr_fmt(fmt) "dpaa2-console: " fmt
  10
  11 #include <linux/module.h>
  12 #include <linux/of_device.h>
  13 #include <linux/of_address.h>
  14 #include <linux/miscdevice.h>
  15 #include <linux/uaccess.h>
  16 #include <linux/slab.h>
  17 #include <linux/fs.h>
  18 #include <linux/io.h>
  19
  20 /* MC firmware base low/high registers indexes */
  21 #define MCFBALR_OFFSET 0
  22 #define MCFBAHR_OFFSET 1
  23
  24 /* Bit masks used to get the most/least significant part of the MC base addr */
  25 #define MC_FW_ADDR_MASK_HIGH 0x1FFFF
  26 #define MC_FW_ADDR_MASK_LOW  0xE0000000
  27
  28 #define MC_BUFFER_OFFSET 0x01000000
  29 #define MC_BUFFER_SIZE   (1024 * 1024 * 16)
  30 #define MC_OFFSET_DELTA  MC_BUFFER_OFFSET
  31
  32 #define AIOP_BUFFER_OFFSET 0x06000000
  33 #define AIOP_BUFFER_SIZE   (1024 * 1024 * 16)
  34 #define AIOP_OFFSET_DELTA  0
  35
  36 #define LOG_HEADER_FLAG_BUFFER_WRAPAROUND 0x80000000
  37 #define LAST_BYTE(a) ((a) & ~(LOG_HEADER_FLAG_BUFFER_WRAPAROUND))
  38
  39 /* MC and AIOP Magic words */
  40 #define MAGIC_MC   0x4d430100
  41 #define MAGIC_AIOP 0x41494F50
  42
  43 struct log_header {
  44         __le32 magic_word;
  45         char reserved[4];
  46         __le32 buf_start;
  47         __le32 buf_length;
  48         __le32 last_byte;
  49 };
  50
  51 struct console_data {
  52         void __iomem *map_addr;
  53         struct log_header __iomem *hdr;
  54         void __iomem *start_addr;
  55         void __iomem *end_addr;
  56         void __iomem *end_of_data;
  57         void __iomem *cur_ptr;
  58 };
  59
  60 static struct resource mc_base_addr;
  61
  62 static inline void adjust_end(struct console_data *cd)
  63 {
  64         u32 last_byte = readl(&cd->hdr->last_byte);
  65
  66         cd->end_of_data = cd->start_addr + LAST_BYTE(last_byte);
  67 }
  68
  69 static u64 get_mc_fw_base_address(void)
  70 {
  71         u64 mcfwbase = 0ULL;
  72         u32 __iomem *mcfbaregs;
  73
  74         mcfbaregs = ioremap(mc_base_addr.start, resource_size(&mc_base_addr));
  75         if (!mcfbaregs) {
  76                 pr_err("could not map MC Firmware Base registers\n");
  77                 return 0;
  78         }
  79
  80         mcfwbase  = readl(mcfbaregs + MCFBAHR_OFFSET) &
  81                           MC_FW_ADDR_MASK_HIGH;
  82         mcfwbase <<= 32;
  83         mcfwbase |= readl(mcfbaregs + MCFBALR_OFFSET) & MC_FW_ADDR_MASK_LOW;
  84         iounmap(mcfbaregs);
  85
  86         pr_debug("MC base address at 0x%016llx\n", mcfwbase);
  87         return mcfwbase;
  88 }
  89
  90 static ssize_t dpaa2_console_size(struct console_data *cd)
  91 {
  92         ssize_t size;
  93
  94         if (cd->cur_ptr <= cd->end_of_data)
  95                 size = cd->end_of_data - cd->cur_ptr;
  96         else
  97                 size = (cd->end_addr - cd->cur_ptr) +
  98                         (cd->end_of_data - cd->start_addr);
  99
 100         return size;
 101 }
 102
 103 static int dpaa2_generic_console_open(struct inode *node, struct file *fp,
 104                                       u64 offset, u64 size,
 105                                       u32 expected_magic,
 106                                       u32 offset_delta)
 107 {
 108         u32 read_magic, wrapped, last_byte, buf_start, buf_length;
 109         struct console_data *cd;
 110         u64 base_addr;
 111         int err;
 112
 113         cd = kmalloc(sizeof(*cd), GFP_KERNEL);
 114         if (!cd)
 115                 return -ENOMEM;
 116
 117         base_addr = get_mc_fw_base_address();
 118         if (!base_addr) {
 119                 err = -EIO;
 120                 goto err_fwba;
 121         }
 122
 123         cd->map_addr = ioremap(base_addr + offset, size);
 124         if (!cd->map_addr) {
 125                 pr_err("cannot map console log memory\n");
 126                 err = -EIO;
 127                 goto err_ioremap;
 128         }
 129
 130         cd->hdr = (struct log_header __iomem *)cd->map_addr;
 131         read_magic = readl(&cd->hdr->magic_word);
 132         last_byte =  readl(&cd->hdr->last_byte);
 133         buf_start =  readl(&cd->hdr->buf_start);
 134         buf_length = readl(&cd->hdr->buf_length);
 135
 136         if (read_magic != expected_magic) {
 137                 pr_warn("expected = %08x, read = %08x\n",
 138                         expected_magic, read_magic);
 139                 err = -EIO;
 140                 goto err_magic;
 141         }
 142
 143         cd->start_addr = cd->map_addr + buf_start - offset_delta;
 144         cd->end_addr = cd->start_addr + buf_length;
 145
 146         wrapped = last_byte & LOG_HEADER_FLAG_BUFFER_WRAPAROUND;
 147
 148         adjust_end(cd);
 149         if (wrapped && cd->end_of_data != cd->end_addr)
 150                 cd->cur_ptr = cd->end_of_data + 1;
 151         else
 152                 cd->cur_ptr = cd->start_addr;
 153
 154         fp->private_data = cd;
 155
 156         return 0;
 157
 158 err_magic:
 159         iounmap(cd->map_addr);
 160
 161 err_ioremap:
 162 err_fwba:
 163         kfree(cd);
 164
 165         return err;
 166 }
 167
 168 static int dpaa2_mc_console_open(struct inode *node, struct file *fp)
 169 {
 170         return dpaa2_generic_console_open(node, fp,
 171                                           MC_BUFFER_OFFSET, MC_BUFFER_SIZE,
 172                                           MAGIC_MC, MC_OFFSET_DELTA);
 173 }
 174
 175 static int dpaa2_aiop_console_open(struct inode *node, struct file *fp)
 176 {
 177         return dpaa2_generic_console_open(node, fp,
 178                                           AIOP_BUFFER_OFFSET, AIOP_BUFFER_SIZE,
 179                                           MAGIC_AIOP, AIOP_OFFSET_DELTA);
 180 }
 181
 182 static int dpaa2_console_close(struct inode *node, struct file *fp)
 183 {
 184         struct console_data *cd = fp->private_data;
 185
 186         iounmap(cd->map_addr);
 187         kfree(cd);
 188         return 0;
 189 }
 190
 191 static ssize_t dpaa2_console_read(struct file *fp, char __user *buf,
 192                                   size_t count, loff_t *f_pos)
 193 {
 194         struct console_data *cd = fp->private_data;
 195         size_t bytes = dpaa2_console_size(cd);
 196         size_t bytes_end = cd->end_addr - cd->cur_ptr;
 197         size_t written = 0;
 198         void *kbuf;
 199         int err;
 200
 201         /* Check if we need to adjust the end of data addr */
 202         adjust_end(cd);
 203
 204         if (cd->end_of_data == cd->cur_ptr)
 205                 return 0;
 206
 207         if (count < bytes)
 208                 bytes = count;
 209
 210         kbuf = kmalloc(bytes, GFP_KERNEL);
 211         if (!kbuf)
 212                 return -ENOMEM;
 213
 214         if (bytes > bytes_end) {
 215                 memcpy_fromio(kbuf, cd->cur_ptr, bytes_end);
 216                 if (copy_to_user(buf, kbuf, bytes_end)) {
 217                         err = -EFAULT;
 218                         goto err_free_buf;
 219                 }
 220                 buf += bytes_end;
 221                 cd->cur_ptr = cd->start_addr;
 222                 bytes -= bytes_end;
 223                 written += bytes_end;
 224         }
 225
 226         memcpy_fromio(kbuf, cd->cur_ptr, bytes);
 227         if (copy_to_user(buf, kbuf, bytes)) {
 228                 err = -EFAULT;
 229                 goto err_free_buf;
 230         }
 231         cd->cur_ptr += bytes;
 232         written += bytes;
 233
 234         return written;
 235
 236 err_free_buf:
 237         kfree(kbuf);
 238
 239         return err;
 240 }
 241
 242 static const struct file_operations dpaa2_mc_console_fops = {
 243         .owner          = THIS_MODULE,
 244         .open           = dpaa2_mc_console_open,
 245         .release        = dpaa2_console_close,
 246         .read           = dpaa2_console_read,
 247 };
 248
 249 static struct miscdevice dpaa2_mc_console_dev = {
 250         .minor = MISC_DYNAMIC_MINOR,
 251         .name = "dpaa2_mc_console",
 252         .fops = &dpaa2_mc_console_fops
 253 };
 254
 255 static const struct file_operations dpaa2_aiop_console_fops = {
 256         .owner          = THIS_MODULE,
 257         .open           = dpaa2_aiop_console_open,
 258         .release        = dpaa2_console_close,
 259         .read           = dpaa2_console_read,
 260 };
 261
 262 static struct miscdevice dpaa2_aiop_console_dev = {
 263         .minor = MISC_DYNAMIC_MINOR,
 264         .name = "dpaa2_aiop_console",
 265         .fops = &dpaa2_aiop_console_fops
 266 };
 267
 268 static int dpaa2_console_probe(struct platform_device *pdev)
 269 {
 270         int error;
 271
 272         error = of_address_to_resource(pdev->dev.of_node, 0, &mc_base_addr);
 273         if (error < 0) {
 274                 pr_err("of_address_to_resource() failed for %pOF with %d\n",
 275                        pdev->dev.of_node, error);
 276                 return error;
 277         }
 278
 279         error = misc_register(&dpaa2_mc_console_dev);
 280         if (error) {
 281                 pr_err("cannot register device %s\n",
 282                        dpaa2_mc_console_dev.name);
 283                 goto err_register_mc;
 284         }
 285
 286         error = misc_register(&dpaa2_aiop_console_dev);
 287         if (error) {
 288                 pr_err("cannot register device %s\n",
 289                        dpaa2_aiop_console_dev.name);
 290                 goto err_register_aiop;
 291         }
 292
 293         return 0;
 294
 295 err_register_aiop:
 296         misc_deregister(&dpaa2_mc_console_dev);
 297 err_register_mc:
 298         return error;
 299 }
 300
 301 static int dpaa2_console_remove(struct platform_device *pdev)
 302 {
 303         misc_deregister(&dpaa2_mc_console_dev);
 304         misc_deregister(&dpaa2_aiop_console_dev);
 305
 306         return 0;
 307 }
 308
 309 static const struct of_device_id dpaa2_console_match_table[] = {
 310         { .compatible = "fsl,dpaa2-console",},
 311         {},
 312 };
 313
 314 MODULE_DEVICE_TABLE(of, dpaa2_console_match_table);
 315
 316 static struct platform_driver dpaa2_console_driver = {
 317         .driver = {
 318                    .name = "dpaa2-console",
 319                    .pm = NULL,
 320                    .of_match_table = dpaa2_console_match_table,
 321                    },
 322         .probe = dpaa2_console_probe,
 323         .remove = dpaa2_console_remove,
 324 };
 325 module_platform_driver(dpaa2_console_driver);
 326
 327 MODULE_LICENSE("Dual BSD/GPL");
 328 MODULE_AUTHOR("Roy Pledge <roy.pledge@nxp.com>");
 329 MODULE_DESCRIPTION("DPAA2 console driver");