target/linux/ipq806x/patches-4.1/037-mtd-add-SMEM-parser-for-QCOM-platforms.patch

   1 From 0501f76b138cf1dc11a313bb7a094da524b79337 Mon Sep 17 00:00:00 2001
   2 From: Mathieu Olivari <mathieu@codeaurora.org>
   3 Date: Thu, 13 Aug 2015 09:53:14 -0700
   4 Subject: [PATCH 3/3] mtd: add SMEM parser for QCOM platforms
   5
   6 On QCOM platforms using MTD devices storage (such as IPQ806x), SMEM is
   7 used to store partition layout. This new parser can now be used to read
   8 SMEM and use it to register an MTD layout according to its content.
   9
  10 Signed-off-by: Mathieu Olivari <mathieu@codeaurora.org>
  11 ---
  12  drivers/mtd/Kconfig          |   7 ++
  13  drivers/mtd/Makefile         |   1 +
  14  drivers/mtd/qcom_smem_part.c | 231 +++++++++++++++++++++++++++++++++++++++++++
  15  3 files changed, 239 insertions(+)
  16  create mode 100644 drivers/mtd/qcom_smem_part.c
  17
  18 --- a/drivers/mtd/Kconfig
  19 +++ b/drivers/mtd/Kconfig
  20 @@ -195,6 +195,13 @@ config MTD_MYLOADER_PARTS
  21           You will still need the parsing functions to be called by the driver
  22           for your particular device. It won't happen automatically.
  23
  24 +config MTD_QCOM_SMEM_PARTS
  25 +       tristate "QCOM SMEM partitioning support"
  26 +       depends on QCOM_SMEM
  27 +       help
  28 +         This provides partitions parser for QCOM devices using SMEM
  29 +         such as IPQ806x.
  30 +
  31  comment "User Modules And Translation Layers"
  32
  33  #
  34 --- /dev/null
  35 +++ b/drivers/mtd/qcom_smem_part.c
  36 @@ -0,0 +1,231 @@
  37 +/*
  38 + * Copyright (c) 2015, The Linux Foundation. All rights reserved.
  39 + *
  40 + * This program is free software; you can redistribute it and/or modify
  41 + * it under the terms of the GNU General Public License version 2 and
  42 + * only version 2 as published by the Free Software Foundation.
  43 + *
  44 + * This program is distributed in the hope that it will be useful,
  45 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
  46 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  47 + * GNU General Public License for more details.
  48 + */
  49 +
  50 +#include <linux/kernel.h>
  51 +#include <linux/device.h>
  52 +#include <linux/slab.h>
  53 +
  54 +#include <linux/mtd/mtd.h>
  55 +#include <linux/mtd/partitions.h>
  56 +#include <linux/spi/spi.h>
  57 +#include <linux/module.h>
  58 +
  59 +#include <linux/soc/qcom/smem.h>
  60 +
  61 +/* Processor/host identifier for the application processor */
  62 +#define SMEM_HOST_APPS                 0
  63 +
  64 +/* SMEM items index */
  65 +#define SMEM_AARM_PARTITION_TABLE      9
  66 +#define SMEM_BOOT_FLASH_TYPE           421
  67 +#define SMEM_BOOT_FLASH_BLOCK_SIZE     424
  68 +
  69 +/* SMEM Flash types */
  70 +#define SMEM_FLASH_NAND                        2
  71 +#define SMEM_FLASH_SPI                 6
  72 +
  73 +#define SMEM_PART_NAME_SZ              16
  74 +#define SMEM_PARTS_MAX                 32
  75 +
  76 +struct smem_partition {
  77 +       char name[SMEM_PART_NAME_SZ];
  78 +       __le32 start;
  79 +       __le32 size;
  80 +       __le32 attr;
  81 +};
  82 +
  83 +struct smem_partition_table {
  84 +       u8 magic[8];
  85 +       __le32 version;
  86 +       __le32 len;
  87 +       struct smem_partition parts[SMEM_PARTS_MAX];
  88 +};
  89 +
  90 +/* SMEM Magic values in partition table */
  91 +static const u8 SMEM_PTABLE_MAGIC[] = {
  92 +       0xaa, 0x73, 0xee, 0x55,
  93 +       0xdb, 0xbd, 0x5e, 0xe3,
  94 +};
  95 +
  96 +static int qcom_smem_get_flash_blksz(u64 **smem_blksz)
  97 +{
  98 +       int ret;
  99 +       size_t size;
 100 +
 101 +       ret = qcom_smem_get(SMEM_HOST_APPS, SMEM_BOOT_FLASH_BLOCK_SIZE,
 102 +                           (void **) smem_blksz, &size);
 103 +
 104 +       if (ret < 0) {
 105 +               pr_err("Unable to read flash blksz from SMEM\n");
 106 +               return -ENOENT;
 107 +       }
 108 +
 109 +       if (size != sizeof(**smem_blksz)) {
 110 +               pr_err("Invalid flash blksz size in SMEM\n");
 111 +               return -EINVAL;
 112 +       }
 113 +
 114 +       return 0;
 115 +}
 116 +
 117 +static int qcom_smem_get_flash_type(u64 **smem_flash_type)
 118 +{
 119 +       int ret;
 120 +       size_t size;
 121 +
 122 +       ret = qcom_smem_get(SMEM_HOST_APPS, SMEM_BOOT_FLASH_TYPE,
 123 +                           (void **) smem_flash_type, &size);
 124 +
 125 +       if (ret < 0) {
 126 +               pr_err("Unable to read flash type from SMEM\n");
 127 +               return -ENOENT;
 128 +       }
 129 +
 130 +       if (size != sizeof(**smem_flash_type)) {
 131 +               pr_err("Invalid flash type size in SMEM\n");
 132 +               return -EINVAL;
 133 +       }
 134 +
 135 +       return 0;
 136 +}
 137 +
 138 +static int qcom_smem_get_flash_partitions(struct smem_partition_table **pparts)
 139 +{
 140 +       int ret;
 141 +       size_t size;
 142 +
 143 +       ret = qcom_smem_get(SMEM_HOST_APPS, SMEM_AARM_PARTITION_TABLE,
 144 +                           (void **) pparts, &size);
 145 +
 146 +       if (ret < 0) {
 147 +               pr_err("Unable to read partition table from SMEM\n");
 148 +               return -ENOENT;
 149 +       }
 150 +
 151 +       return 0;
 152 +}
 153 +
 154 +static int of_dev_node_match(struct device *dev, void *data)
 155 +{
 156 +       return dev->of_node == data;
 157 +}
 158 +
 159 +static bool is_spi_device(struct device_node *np)
 160 +{
 161 +       struct device *dev;
 162 +
 163 +       dev = bus_find_device(&spi_bus_type, NULL, np, of_dev_node_match);
 164 +       if (!dev)
 165 +               return false;
 166 +
 167 +       put_device(dev);
 168 +       return true;
 169 +}
 170 +
 171 +static int parse_qcom_smem_partitions(struct mtd_info *master,
 172 +                                     struct mtd_partition **pparts,
 173 +                                     struct mtd_part_parser_data *data)
 174 +{
 175 +       struct smem_partition_table *smem_parts;
 176 +       u64 *smem_flash_type, *smem_blksz;
 177 +       struct mtd_partition *mtd_parts;
 178 +       struct device_node *of_node = data->of_node;
 179 +       int i, ret;
 180 +
 181 +       /*
 182 +        * SMEM will only store the partition table of the boot device.
 183 +        * If this is not the boot device, do not return any partition.
 184 +        */
 185 +       ret = qcom_smem_get_flash_type(&smem_flash_type);
 186 +       if (ret < 0)
 187 +               return ret;
 188 +
 189 +       if ((*smem_flash_type == SMEM_FLASH_NAND && !mtd_type_is_nand(master))
 190 +           || (*smem_flash_type == SMEM_FLASH_SPI && !is_spi_device(of_node)))
 191 +               return 0;
 192 +
 193 +       /*
 194 +        * Just for sanity purpose, make sure the block size in SMEM matches the
 195 +        * block size of the MTD device
 196 +        */
 197 +       ret = qcom_smem_get_flash_blksz(&smem_blksz);
 198 +       if (ret < 0)
 199 +               return ret;
 200 +
 201 +       if (*smem_blksz != master->erasesize) {
 202 +               pr_err("SMEM block size differs from MTD block size\n");
 203 +               return -EINVAL;
 204 +       }
 205 +
 206 +       /* Get partition pointer from SMEM */
 207 +       ret = qcom_smem_get_flash_partitions(&smem_parts);
 208 +       if (ret < 0)
 209 +               return ret;
 210 +
 211 +       if (memcmp(SMEM_PTABLE_MAGIC, smem_parts->magic,
 212 +                  sizeof(SMEM_PTABLE_MAGIC))) {
 213 +               pr_err("SMEM partition magic invalid\n");
 214 +               return -EINVAL;
 215 +       }
 216 +
 217 +       /* Allocate and populate the mtd structures */
 218 +       mtd_parts = kcalloc(le32_to_cpu(smem_parts->len), sizeof(*mtd_parts),
 219 +                           GFP_KERNEL);
 220 +       if (!mtd_parts)
 221 +               return -ENOMEM;
 222 +
 223 +       for (i = 0; i < smem_parts->len; i++) {
 224 +               struct smem_partition *s_part = &smem_parts->parts[i];
 225 +               struct mtd_partition *m_part = &mtd_parts[i];
 226 +
 227 +               m_part->name = s_part->name;
 228 +               m_part->size = le32_to_cpu(s_part->size) * (*smem_blksz);
 229 +               m_part->offset = le32_to_cpu(s_part->start) * (*smem_blksz);
 230 +
 231 +               /*
 232 +                * The last SMEM partition may have its size marked as
 233 +                * something like 0xffffffff, which means "until the end of the
 234 +                * flash device". In this case, truncate it.
 235 +                */
 236 +               if (m_part->offset + m_part->size > master->size)
 237 +                       m_part->size = master->size - m_part->offset;
 238 +       }
 239 +
 240 +       *pparts = mtd_parts;
 241 +
 242 +       return smem_parts->len;
 243 +}
 244 +
 245 +static struct mtd_part_parser qcom_smem_parser = {
 246 +       .owner = THIS_MODULE,
 247 +       .parse_fn = parse_qcom_smem_partitions,
 248 +       .name = "qcom-smem",
 249 +};
 250 +
 251 +static int __init qcom_smem_parser_init(void)
 252 +{
 253 +       register_mtd_parser(&qcom_smem_parser);
 254 +       return 0;
 255 +}
 256 +
 257 +static void __exit qcom_smem_parser_exit(void)
 258 +{
 259 +       deregister_mtd_parser(&qcom_smem_parser);
 260 +}
 261 +
 262 +module_init(qcom_smem_parser_init);
 263 +module_exit(qcom_smem_parser_exit);
 264 +
 265 +MODULE_LICENSE("GPL");
 266 +MODULE_AUTHOR("Mathieu Olivari <mathieu@codeaurora.org>");
 267 +MODULE_DESCRIPTION("Parsing code for SMEM based partition tables");
 268 --- a/drivers/mtd/Makefile
 269 +++ b/drivers/mtd/Makefile
 270 @@ -16,6 +16,7 @@ obj-$(CONFIG_MTD_AR7_PARTS)   += ar7part.o
 271  obj-$(CONFIG_MTD_BCM63XX_PARTS)        += bcm63xxpart.o
 272  obj-$(CONFIG_MTD_BCM47XX_PARTS)        += bcm47xxpart.o
 273  obj-$(CONFIG_MTD_MYLOADER_PARTS) += myloader.o
 274 +obj-$(CONFIG_MTD_QCOM_SMEM_PARTS) += qcom_smem_part.o
 275
 276  # 'Users' - code which presents functionality to userspace.
 277  obj-$(CONFIG_MTD_BLKDEVS)      += mtd_blkdevs.o