target/linux/ipq806x/patches-4.4/037-mtd-add-SMEM-parser-for-QCOM-platforms.patch

   1 From 61e8e1b1af77f24339da3f0822a76fa65ed635c6 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] 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 Signed-off-by: Ram Chandra Jangir <rjangi@codeaurora.org>
  12 ---
  13  drivers/mtd/Kconfig          |   7 ++
  14  drivers/mtd/Makefile         |   1 +
  15  drivers/mtd/qcom_smem_part.c | 228 +++++++++++++++++++++++++++++++++++++++++++
  16  3 files changed, 236 insertions(+)
  17  create mode 100644 drivers/mtd/qcom_smem_part.c
  18
  19 --- a/drivers/mtd/Kconfig
  20 +++ b/drivers/mtd/Kconfig
  21 @@ -190,6 +190,13 @@ config MTD_MYLOADER_PARTS
  22           You will still need the parsing functions to be called by the driver
  23           for your particular device. It won't happen automatically.
  24
  25 +config MTD_QCOM_SMEM_PARTS
  26 +       tristate "QCOM SMEM partitioning support"
  27 +       depends on QCOM_SMEM
  28 +       help
  29 +         This provides partitions parser for QCOM devices using SMEM
  30 +         such as IPQ806x.
  31 +
  32  comment "User Modules And Translation Layers"
  33
  34  #
  35 --- a/drivers/mtd/Makefile
  36 +++ b/drivers/mtd/Makefile
  37 @@ -16,6 +16,7 @@ obj-$(CONFIG_MTD_AR7_PARTS)   += ar7part.o
  38  obj-$(CONFIG_MTD_BCM63XX_PARTS)        += bcm63xxpart.o
  39  obj-$(CONFIG_MTD_BCM47XX_PARTS)        += bcm47xxpart.o
  40  obj-$(CONFIG_MTD_MYLOADER_PARTS) += myloader.o
  41 +obj-$(CONFIG_MTD_QCOM_SMEM_PARTS) += qcom_smem_part.o
  42
  43  # 'Users' - code which presents functionality to userspace.
  44  obj-$(CONFIG_MTD_BLKDEVS)      += mtd_blkdevs.o
  45 --- /dev/null
  46 +++ b/drivers/mtd/qcom_smem_part.c
  47 @@ -0,0 +1,228 @@
  48 +/*
  49 + * Copyright (c) 2015, The Linux Foundation. All rights reserved.
  50 + *
  51 + * This program is free software; you can redistribute it and/or modify
  52 + * it under the terms of the GNU General Public License version 2 and
  53 + * only version 2 as published by the Free Software Foundation.
  54 + *
  55 + * This program is distributed in the hope that it will be useful,
  56 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
  57 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  58 + * GNU General Public License for more details.
  59 + */
  60 +
  61 +#include <linux/kernel.h>
  62 +#include <linux/device.h>
  63 +#include <linux/slab.h>
  64 +
  65 +#include <linux/mtd/mtd.h>
  66 +#include <linux/mtd/partitions.h>
  67 +#include <linux/spi/spi.h>
  68 +#include <linux/module.h>
  69 +
  70 +#include <linux/soc/qcom/smem.h>
  71 +
  72 +/* Processor/host identifier for the application processor */
  73 +#define SMEM_HOST_APPS                 0
  74 +
  75 +/* SMEM items index */
  76 +#define SMEM_AARM_PARTITION_TABLE      9
  77 +#define SMEM_BOOT_FLASH_TYPE           421
  78 +#define SMEM_BOOT_FLASH_BLOCK_SIZE     424
  79 +
  80 +/* SMEM Flash types */
  81 +#define SMEM_FLASH_NAND                        2
  82 +#define SMEM_FLASH_SPI                 6
  83 +
  84 +#define SMEM_PART_NAME_SZ              16
  85 +#define SMEM_PARTS_MAX                 32
  86 +
  87 +struct smem_partition {
  88 +       char name[SMEM_PART_NAME_SZ];
  89 +       __le32 start;
  90 +       __le32 size;
  91 +       __le32 attr;
  92 +};
  93 +
  94 +struct smem_partition_table {
  95 +       u8 magic[8];
  96 +       __le32 version;
  97 +       __le32 len;
  98 +       struct smem_partition parts[SMEM_PARTS_MAX];
  99 +};
 100 +
 101 +/* SMEM Magic values in partition table */
 102 +static const u8 SMEM_PTABLE_MAGIC[] = {
 103 +       0xaa, 0x73, 0xee, 0x55,
 104 +       0xdb, 0xbd, 0x5e, 0xe3,
 105 +};
 106 +
 107 +static int qcom_smem_get_flash_blksz(u64 **smem_blksz)
 108 +{
 109 +       size_t size;
 110 +
 111 +       *smem_blksz = qcom_smem_get(SMEM_HOST_APPS, SMEM_BOOT_FLASH_BLOCK_SIZE,
 112 +                                   &size);
 113 +
 114 +       if (IS_ERR(*smem_blksz)) {
 115 +               pr_err("Unable to read flash blksz from SMEM\n");
 116 +               return -ENOENT;
 117 +       }
 118 +
 119 +       if (size != sizeof(**smem_blksz)) {
 120 +               pr_err("Invalid flash blksz size in SMEM\n");
 121 +               return -EINVAL;
 122 +       }
 123 +
 124 +       return 0;
 125 +}
 126 +
 127 +static int qcom_smem_get_flash_type(u64 **smem_flash_type)
 128 +{
 129 +       size_t size;
 130 +
 131 +       *smem_flash_type = qcom_smem_get(SMEM_HOST_APPS, SMEM_BOOT_FLASH_TYPE,
 132 +                                       &size);
 133 +
 134 +       if (IS_ERR(*smem_flash_type)) {
 135 +               pr_err("Unable to read flash type from SMEM\n");
 136 +               return -ENOENT;
 137 +       }
 138 +
 139 +       if (size != sizeof(**smem_flash_type)) {
 140 +               pr_err("Invalid flash type size in SMEM\n");
 141 +               return -EINVAL;
 142 +       }
 143 +
 144 +       return 0;
 145 +}
 146 +
 147 +static int qcom_smem_get_flash_partitions(struct smem_partition_table **pparts)
 148 +{
 149 +       size_t size;
 150 +
 151 +       *pparts = qcom_smem_get(SMEM_HOST_APPS, SMEM_AARM_PARTITION_TABLE,
 152 +                               &size);
 153 +
 154 +       if (IS_ERR(*pparts)) {
 155 +               pr_err("Unable to read partition table from SMEM\n");
 156 +               return -ENOENT;
 157 +       }
 158 +
 159 +       return 0;
 160 +}
 161 +
 162 +static int of_dev_node_match(struct device *dev, void *data)
 163 +{
 164 +       return dev->of_node == data;
 165 +}
 166 +
 167 +static bool is_spi_device(struct device_node *np)
 168 +{
 169 +       struct device *dev;
 170 +
 171 +       dev = bus_find_device(&spi_bus_type, NULL, np, of_dev_node_match);
 172 +       if (!dev)
 173 +               return false;
 174 +
 175 +       put_device(dev);
 176 +       return true;
 177 +}
 178 +
 179 +static int parse_qcom_smem_partitions(struct mtd_info *master,
 180 +                                     struct mtd_partition **pparts,
 181 +                                     struct mtd_part_parser_data *data)
 182 +{
 183 +       struct smem_partition_table *smem_parts;
 184 +       u64 *smem_flash_type, *smem_blksz;
 185 +       struct mtd_partition *mtd_parts;
 186 +       struct device_node *of_node = data->of_node;
 187 +       int i, ret;
 188 +
 189 +       /*
 190 +        * SMEM will only store the partition table of the boot device.
 191 +        * If this is not the boot device, do not return any partition.
 192 +        */
 193 +       ret = qcom_smem_get_flash_type(&smem_flash_type);
 194 +       if (ret < 0)
 195 +               return ret;
 196 +
 197 +       if ((*smem_flash_type == SMEM_FLASH_NAND && !mtd_type_is_nand(master))
 198 +           || (*smem_flash_type == SMEM_FLASH_SPI && !is_spi_device(of_node)))
 199 +               return 0;
 200 +
 201 +       /*
 202 +        * Just for sanity purpose, make sure the block size in SMEM matches the
 203 +        * block size of the MTD device
 204 +        */
 205 +       ret = qcom_smem_get_flash_blksz(&smem_blksz);
 206 +       if (ret < 0)
 207 +               return ret;
 208 +
 209 +       if (*smem_blksz != master->erasesize) {
 210 +               pr_err("SMEM block size differs from MTD block size\n");
 211 +               return -EINVAL;
 212 +       }
 213 +
 214 +       /* Get partition pointer from SMEM */
 215 +       ret = qcom_smem_get_flash_partitions(&smem_parts);
 216 +       if (ret < 0)
 217 +               return ret;
 218 +
 219 +       if (memcmp(SMEM_PTABLE_MAGIC, smem_parts->magic,
 220 +                  sizeof(SMEM_PTABLE_MAGIC))) {
 221 +               pr_err("SMEM partition magic invalid\n");
 222 +               return -EINVAL;
 223 +       }
 224 +
 225 +       /* Allocate and populate the mtd structures */
 226 +       mtd_parts = kcalloc(le32_to_cpu(smem_parts->len), sizeof(*mtd_parts),
 227 +                           GFP_KERNEL);
 228 +       if (!mtd_parts)
 229 +               return -ENOMEM;
 230 +
 231 +       for (i = 0; i < smem_parts->len; i++) {
 232 +               struct smem_partition *s_part = &smem_parts->parts[i];
 233 +               struct mtd_partition *m_part = &mtd_parts[i];
 234 +
 235 +               m_part->name = s_part->name;
 236 +               m_part->size = le32_to_cpu(s_part->size) * (*smem_blksz);
 237 +               m_part->offset = le32_to_cpu(s_part->start) * (*smem_blksz);
 238 +
 239 +               /*
 240 +                * The last SMEM partition may have its size marked as
 241 +                * something like 0xffffffff, which means "until the end of the
 242 +                * flash device". In this case, truncate it.
 243 +                */
 244 +               if (m_part->offset + m_part->size > master->size)
 245 +                       m_part->size = master->size - m_part->offset;
 246 +       }
 247 +
 248 +       *pparts = mtd_parts;
 249 +
 250 +       return smem_parts->len;
 251 +}
 252 +
 253 +static struct mtd_part_parser qcom_smem_parser = {
 254 +       .owner = THIS_MODULE,
 255 +       .parse_fn = parse_qcom_smem_partitions,
 256 +       .name = "qcom-smem",
 257 +};
 258 +
 259 +static int __init qcom_smem_parser_init(void)
 260 +{
 261 +       register_mtd_parser(&qcom_smem_parser);
 262 +       return 0;
 263 +}
 264 +
 265 +static void __exit qcom_smem_parser_exit(void)
 266 +{
 267 +       deregister_mtd_parser(&qcom_smem_parser);
 268 +}
 269 +
 270 +module_init(qcom_smem_parser_init);
 271 +module_exit(qcom_smem_parser_exit);
 272 +
 273 +MODULE_LICENSE("GPL");
 274 +MODULE_AUTHOR("Mathieu Olivari <mathieu@codeaurora.org>");
 275 +MODULE_DESCRIPTION("Parsing code for SMEM based partition tables");