1 files changed, 346 insertions, 0 deletions

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 83240faa1dc8..5db49b124ffa 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1050,6 +1050,352 @@ void mmc_detect_change(struct mmc_host *host, unsigned long delay)
 
 EXPORT_SYMBOL(mmc_detect_change);
 
+void mmc_init_erase(struct mmc_card *card)
+{
+        unsigned int sz;
+
+        if (is_power_of_2(card->erase_size))
+                card->erase_shift = ffs(card->erase_size) - 1;
+        else
+                card->erase_shift = 0;
+
+        /*
+         * It is possible to erase an arbitrarily large area of an SD or MMC
+         * card.  That is not desirable because it can take a long time
+         * (minutes) potentially delaying more important I/O, and also the
+         * timeout calculations become increasingly hugely over-estimated.
+         * Consequently, 'pref_erase' is defined as a guide to limit erases
+         * to that size and alignment.
+         *
+         * For SD cards that define Allocation Unit size, limit erases to one
+         * Allocation Unit at a time.  For MMC cards that define High Capacity
+         * Erase Size, whether it is switched on or not, limit to that size.
+         * Otherwise just have a stab at a good value.  For modern cards it
+         * will end up being 4MiB.  Note that if the value is too small, it
+         * can end up taking longer to erase.
+         */
+        if (mmc_card_sd(card) && card->ssr.au) {
+                card->pref_erase = card->ssr.au;
+                card->erase_shift = ffs(card->ssr.au) - 1;
+        } else if (card->ext_csd.hc_erase_size) {
+                card->pref_erase = card->ext_csd.hc_erase_size;
+        } else {
+                sz = (card->csd.capacity << (card->csd.read_blkbits - 9)) >> 11;
+                if (sz < 128)
+                        card->pref_erase = 512 * 1024 / 512;
+                else if (sz < 512)
+                        card->pref_erase = 1024 * 1024 / 512;
+                else if (sz < 1024)
+                        card->pref_erase = 2 * 1024 * 1024 / 512;
+                else
+                        card->pref_erase = 4 * 1024 * 1024 / 512;
+                if (card->pref_erase < card->erase_size)
+                        card->pref_erase = card->erase_size;
+                else {
+                        sz = card->pref_erase % card->erase_size;
+                        if (sz)
+                                card->pref_erase += card->erase_size - sz;
+                }
+        }
+}
+
+static void mmc_set_mmc_erase_timeout(struct mmc_card *card,
+                                      struct mmc_command *cmd,
+                                      unsigned int arg, unsigned int qty)
+{
+        unsigned int erase_timeout;
+
+        if (card->ext_csd.erase_group_def & 1) {
+                /* High Capacity Erase Group Size uses HC timeouts */
+                if (arg == MMC_TRIM_ARG)
+                        erase_timeout = card->ext_csd.trim_timeout;
+                else
+                        erase_timeout = card->ext_csd.hc_erase_timeout;
+        } else {
+                /* CSD Erase Group Size uses write timeout */
+                unsigned int mult = (10 << card->csd.r2w_factor);
+                unsigned int timeout_clks = card->csd.tacc_clks * mult;
+                unsigned int timeout_us;
+
+                /* Avoid overflow: e.g. tacc_ns=80000000 mult=1280 */
+                if (card->csd.tacc_ns < 1000000)
+                        timeout_us = (card->csd.tacc_ns * mult) / 1000;
+                else
+                        timeout_us = (card->csd.tacc_ns / 1000) * mult;
+
+                /*
+                 * ios.clock is only a target.  The real clock rate might be
+                 * less but not that much less, so fudge it by multiplying by 2.
+                 */
+                timeout_clks <<= 1;
+                timeout_us += (timeout_clks * 1000) /
+                              (card->host->ios.clock / 1000);
+
+                erase_timeout = timeout_us / 1000;
+
+                /*
+                 * Theoretically, the calculation could underflow so round up
+                 * to 1ms in that case.
+                 */
+                if (!erase_timeout)
+                        erase_timeout = 1;
+        }
+
+        /* Multiplier for secure operations */
+        if (arg & MMC_SECURE_ARGS) {
+                if (arg == MMC_SECURE_ERASE_ARG)
+                        erase_timeout *= card->ext_csd.sec_erase_mult;
+                else
+                        erase_timeout *= card->ext_csd.sec_trim_mult;
+        }
+
+        erase_timeout *= qty;
+
+        /*
+         * Ensure at least a 1 second timeout for SPI as per
+         * 'mmc_set_data_timeout()'
+         */
+        if (mmc_host_is_spi(card->host) && erase_timeout < 1000)
+                erase_timeout = 1000;
+
+        cmd->erase_timeout = erase_timeout;
+}
+
+static void mmc_set_sd_erase_timeout(struct mmc_card *card,
+                                     struct mmc_command *cmd, unsigned int arg,
+                                     unsigned int qty)
+{
+        if (card->ssr.erase_timeout) {
+                /* Erase timeout specified in SD Status Register (SSR) */
+                cmd->erase_timeout = card->ssr.erase_timeout * qty +
+                                     card->ssr.erase_offset;
+        } else {
+                /*
+                 * Erase timeout not specified in SD Status Register (SSR) so
+                 * use 250ms per write block.
+                 */
+                cmd->erase_timeout = 250 * qty;
+        }
+
+        /* Must not be less than 1 second */
+        if (cmd->erase_timeout < 1000)
+                cmd->erase_timeout = 1000;
+}
+
+static void mmc_set_erase_timeout(struct mmc_card *card,
+                                  struct mmc_command *cmd, unsigned int arg,
+                                  unsigned int qty)
+{
+        if (mmc_card_sd(card))
+                mmc_set_sd_erase_timeout(card, cmd, arg, qty);
+        else
+                mmc_set_mmc_erase_timeout(card, cmd, arg, qty);
+}
+
+static int mmc_do_erase(struct mmc_card *card, unsigned int from,
+                        unsigned int to, unsigned int arg)
+{
+        struct mmc_command cmd;
+        unsigned int qty = 0;
+        int err;
+
+        /*
+         * qty is used to calculate the erase timeout which depends on how many
+         * erase groups (or allocation units in SD terminology) are affected.
+         * We count erasing part of an erase group as one erase group.
+         * For SD, the allocation units are always a power of 2.  For MMC, the
+         * erase group size is almost certainly also power of 2, but it does not
+         * seem to insist on that in the JEDEC standard, so we fall back to
+         * division in that case.  SD may not specify an allocation unit size,
+         * in which case the timeout is based on the number of write blocks.
+         *
+         * Note that the timeout for secure trim 2 will only be correct if the
+         * number of erase groups specified is the same as the total of all
+         * preceding secure trim 1 commands.  Since the power may have been
+         * lost since the secure trim 1 commands occurred, it is generally
+         * impossible to calculate the secure trim 2 timeout correctly.
+         */
+        if (card->erase_shift)
+                qty += ((to >> card->erase_shift) -
+                        (from >> card->erase_shift)) + 1;
+        else if (mmc_card_sd(card))
+                qty += to - from + 1;
+        else
+                qty += ((to / card->erase_size) -
+                        (from / card->erase_size)) + 1;
+
+        if (!mmc_card_blockaddr(card)) {
+                from <<= 9;
+                to <<= 9;
+        }
+
+        memset(&cmd, 0, sizeof(struct mmc_command));
+        if (mmc_card_sd(card))
+                cmd.opcode = SD_ERASE_WR_BLK_START;
+        else
+                cmd.opcode = MMC_ERASE_GROUP_START;
+        cmd.arg = from;
+        cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
+        err = mmc_wait_for_cmd(card->host, &cmd, 0);
+        if (err) {
+                printk(KERN_ERR "mmc_erase: group start error %d, "
+                       "status %#x\n", err, cmd.resp[0]);
+                err = -EINVAL;
+                goto out;
+        }
+
+        memset(&cmd, 0, sizeof(struct mmc_command));
+        if (mmc_card_sd(card))
+                cmd.opcode = SD_ERASE_WR_BLK_END;
+        else
+                cmd.opcode = MMC_ERASE_GROUP_END;
+        cmd.arg = to;
+        cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
+        err = mmc_wait_for_cmd(card->host, &cmd, 0);
+        if (err) {
+                printk(KERN_ERR "mmc_erase: group end error %d, status %#x\n",
+                       err, cmd.resp[0]);
+                err = -EINVAL;
+                goto out;
+        }
+
+        memset(&cmd, 0, sizeof(struct mmc_command));
+        cmd.opcode = MMC_ERASE;
+        cmd.arg = arg;
+        cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
+        mmc_set_erase_timeout(card, &cmd, arg, qty);
+        err = mmc_wait_for_cmd(card->host, &cmd, 0);
+        if (err) {
+                printk(KERN_ERR "mmc_erase: erase error %d, status %#x\n",
+                       err, cmd.resp[0]);
+                err = -EIO;
+                goto out;
+        }
+
+        if (mmc_host_is_spi(card->host))
+                goto out;
+
+        do {
+                memset(&cmd, 0, sizeof(struct mmc_command));
+                cmd.opcode = MMC_SEND_STATUS;
+                cmd.arg = card->rca << 16;
+                cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
+                /* Do not retry else we can't see errors */
+                err = mmc_wait_for_cmd(card->host, &cmd, 0);
+                if (err || (cmd.resp[0] & 0xFDF92000)) {
+                        printk(KERN_ERR "error %d requesting status %#x\n",
+                                err, cmd.resp[0]);
+                        err = -EIO;
+                        goto out;
+                }
+        } while (!(cmd.resp[0] & R1_READY_FOR_DATA) ||
+                 R1_CURRENT_STATE(cmd.resp[0]) == 7);
+out:
+        return err;
+}
+
+/**
+ * mmc_erase - erase sectors.
+ * @card: card to erase
+ * @from: first sector to erase
+ * @nr: number of sectors to erase
+ * @arg: erase command argument (SD supports only %MMC_ERASE_ARG)
+ *
+ * Caller must claim host before calling this function.
+ */
+int mmc_erase(struct mmc_card *card, unsigned int from, unsigned int nr,
+              unsigned int arg)
+{
+        unsigned int rem, to = from + nr;
+
+        if (!(card->host->caps & MMC_CAP_ERASE) ||
+            !(card->csd.cmdclass & CCC_ERASE))
+                return -EOPNOTSUPP;
+
+        if (!card->erase_size)
+                return -EOPNOTSUPP;
+
+        if (mmc_card_sd(card) && arg != MMC_ERASE_ARG)
+                return -EOPNOTSUPP;
+
+        if ((arg & MMC_SECURE_ARGS) &&
+            !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN))
+                return -EOPNOTSUPP;
+
+        if ((arg & MMC_TRIM_ARGS) &&
+            !(card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN))
+                return -EOPNOTSUPP;
+
+        if (arg == MMC_SECURE_ERASE_ARG) {
+                if (from % card->erase_size || nr % card->erase_size)
+                        return -EINVAL;
+        }
+
+        if (arg == MMC_ERASE_ARG) {
+                rem = from % card->erase_size;
+                if (rem) {
+                        rem = card->erase_size - rem;
+                        from += rem;
+                        if (nr > rem)
+                                nr -= rem;
+                        else
+                                return 0;
+                }
+                rem = nr % card->erase_size;
+                if (rem)
+                        nr -= rem;
+        }
+
+        if (nr == 0)
+                return 0;
+
+        to = from + nr;
+
+        if (to <= from)
+                return -EINVAL;
+
+        /* 'from' and 'to' are inclusive */
+        to -= 1;
+
+        return mmc_do_erase(card, from, to, arg);
+}
+EXPORT_SYMBOL(mmc_erase);
+
+int mmc_can_erase(struct mmc_card *card)
+{
+        if ((card->host->caps & MMC_CAP_ERASE) &&
+            (card->csd.cmdclass & CCC_ERASE) && card->erase_size)
+                return 1;
+        return 0;
+}
+EXPORT_SYMBOL(mmc_can_erase);
+
+int mmc_can_trim(struct mmc_card *card)
+{
+        if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN)
+                return 1;
+        return 0;
+}
+EXPORT_SYMBOL(mmc_can_trim);
+
+int mmc_can_secure_erase_trim(struct mmc_card *card)
+{
+        if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_ER_EN)
+                return 1;
+        return 0;
+}
+EXPORT_SYMBOL(mmc_can_secure_erase_trim);
+
+int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
+                            unsigned int nr)
+{
+        if (!card->erase_size)
+                return 0;
+        if (from % card->erase_size || nr % card->erase_size)
+                return 0;
+        return 1;
+}
+EXPORT_SYMBOL(mmc_erase_group_aligned);
 
 void mmc_rescan(struct work_struct *work)
 {