diff options
Diffstat (limited to 'drivers/block/rsxx/config.c')
| -rw-r--r-- | drivers/block/rsxx/config.c | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/drivers/block/rsxx/config.c b/drivers/block/rsxx/config.c new file mode 100644 index 000000000..10cd530d3 --- /dev/null +++ b/drivers/block/rsxx/config.c @@ -0,0 +1,211 @@ +/* +* Filename: config.c +* +* +* Authors: Joshua Morris <josh.h.morris@us.ibm.com> +* Philip Kelleher <pjk1939@linux.vnet.ibm.com> +* +* (C) Copyright 2013 IBM Corporation +* +* This program is free software; you can redistribute it and/or +* modify it under the terms of the GNU General Public License as +* published by the Free Software Foundation; either version 2 of the +* License, or (at your option) any later version. +* +* This program is distributed in the hope that it will be useful, but +* WITHOUT ANY WARRANTY; without even the implied warranty of +* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +* General Public License for more details. +* +* You should have received a copy of the GNU General Public License +* along with this program; if not, write to the Free Software Foundation, +* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +*/ + +#include <linux/types.h> +#include <linux/crc32.h> +#include <linux/swab.h> + +#include "rsxx_priv.h" +#include "rsxx_cfg.h" + +static void initialize_config(struct rsxx_card_cfg *cfg) +{ + cfg->hdr.version = RSXX_CFG_VERSION; + + cfg->data.block_size = RSXX_HW_BLK_SIZE; + cfg->data.stripe_size = RSXX_HW_BLK_SIZE; + cfg->data.vendor_id = RSXX_VENDOR_ID_IBM; + cfg->data.cache_order = (-1); + cfg->data.intr_coal.mode = RSXX_INTR_COAL_DISABLED; + cfg->data.intr_coal.count = 0; + cfg->data.intr_coal.latency = 0; +} + +static u32 config_data_crc32(struct rsxx_card_cfg *cfg) +{ + /* + * Return the compliment of the CRC to ensure compatibility + * (i.e. this is how early rsxx drivers did it.) + */ + + return ~crc32(~0, &cfg->data, sizeof(cfg->data)); +} + + +/*----------------- Config Byte Swap Functions -------------------*/ +static void config_hdr_be_to_cpu(struct card_cfg_hdr *hdr) +{ + hdr->version = be32_to_cpu((__force __be32) hdr->version); + hdr->crc = be32_to_cpu((__force __be32) hdr->crc); +} + +static void config_hdr_cpu_to_be(struct card_cfg_hdr *hdr) +{ + hdr->version = (__force u32) cpu_to_be32(hdr->version); + hdr->crc = (__force u32) cpu_to_be32(hdr->crc); +} + +static void config_data_swab(struct rsxx_card_cfg *cfg) +{ + u32 *data = (u32 *) &cfg->data; + int i; + + for (i = 0; i < (sizeof(cfg->data) / 4); i++) + data[i] = swab32(data[i]); +} + +static void config_data_le_to_cpu(struct rsxx_card_cfg *cfg) +{ + u32 *data = (u32 *) &cfg->data; + int i; + + for (i = 0; i < (sizeof(cfg->data) / 4); i++) + data[i] = le32_to_cpu((__force __le32) data[i]); +} + +static void config_data_cpu_to_le(struct rsxx_card_cfg *cfg) +{ + u32 *data = (u32 *) &cfg->data; + int i; + + for (i = 0; i < (sizeof(cfg->data) / 4); i++) + data[i] = (__force u32) cpu_to_le32(data[i]); +} + + +/*----------------- Config Operations ------------------*/ +static int rsxx_save_config(struct rsxx_cardinfo *card) +{ + struct rsxx_card_cfg cfg; + int st; + + memcpy(&cfg, &card->config, sizeof(cfg)); + + if (unlikely(cfg.hdr.version != RSXX_CFG_VERSION)) { + dev_err(CARD_TO_DEV(card), + "Cannot save config with invalid version %d\n", + cfg.hdr.version); + return -EINVAL; + } + + /* Convert data to little endian for the CRC calculation. */ + config_data_cpu_to_le(&cfg); + + cfg.hdr.crc = config_data_crc32(&cfg); + + /* + * Swap the data from little endian to big endian so it can be + * stored. + */ + config_data_swab(&cfg); + config_hdr_cpu_to_be(&cfg.hdr); + + st = rsxx_creg_write(card, CREG_ADD_CONFIG, sizeof(cfg), &cfg, 1); + if (st) + return st; + + return 0; +} + +int rsxx_load_config(struct rsxx_cardinfo *card) +{ + int st; + u32 crc; + + st = rsxx_creg_read(card, CREG_ADD_CONFIG, sizeof(card->config), + &card->config, 1); + if (st) { + dev_err(CARD_TO_DEV(card), + "Failed reading card config.\n"); + return st; + } + + config_hdr_be_to_cpu(&card->config.hdr); + + if (card->config.hdr.version == RSXX_CFG_VERSION) { + /* + * We calculate the CRC with the data in little endian, because + * early drivers did not take big endian CPUs into account. + * The data is always stored in big endian, so we need to byte + * swap it before calculating the CRC. + */ + + config_data_swab(&card->config); + + /* Check the CRC */ + crc = config_data_crc32(&card->config); + if (crc != card->config.hdr.crc) { + dev_err(CARD_TO_DEV(card), + "Config corruption detected!\n"); + dev_info(CARD_TO_DEV(card), + "CRC (sb x%08x is x%08x)\n", + card->config.hdr.crc, crc); + return -EIO; + } + + /* Convert the data to CPU byteorder */ + config_data_le_to_cpu(&card->config); + + } else if (card->config.hdr.version != 0) { + dev_err(CARD_TO_DEV(card), + "Invalid config version %d.\n", + card->config.hdr.version); + /* + * Config version changes require special handling from the + * user + */ + return -EINVAL; + } else { + dev_info(CARD_TO_DEV(card), + "Initializing card configuration.\n"); + initialize_config(&card->config); + st = rsxx_save_config(card); + if (st) + return st; + } + + card->config_valid = 1; + + dev_dbg(CARD_TO_DEV(card), "version: x%08x\n", + card->config.hdr.version); + dev_dbg(CARD_TO_DEV(card), "crc: x%08x\n", + card->config.hdr.crc); + dev_dbg(CARD_TO_DEV(card), "block_size: x%08x\n", + card->config.data.block_size); + dev_dbg(CARD_TO_DEV(card), "stripe_size: x%08x\n", + card->config.data.stripe_size); + dev_dbg(CARD_TO_DEV(card), "vendor_id: x%08x\n", + card->config.data.vendor_id); + dev_dbg(CARD_TO_DEV(card), "cache_order: x%08x\n", + card->config.data.cache_order); + dev_dbg(CARD_TO_DEV(card), "mode: x%08x\n", + card->config.data.intr_coal.mode); + dev_dbg(CARD_TO_DEV(card), "count: x%08x\n", + card->config.data.intr_coal.count); + dev_dbg(CARD_TO_DEV(card), "latency: x%08x\n", + card->config.data.intr_coal.latency); + + return 0; +} + |