>From e2b3bc79dd1f76b21701e5e6757121c89f7add71 Mon Sep 17 00:00:00 2001
From: Chuanxiao Dong <[email protected]>
Date: Sat, 13 Nov 2010 19:41:45 +0800
Subject: [PATCH 2/4] mmc: add erase timeout calculation routine for sdhci host

Erase command needs R1b response which means after HD handle
a CMD_RESPONSE interrupt, driver also need to wait for a while.
For SDHCI host controller, HD also need to handle a DATA_END
interrupt.
During device handle erase cmd, if the blocks need to be erased
are too many, some SDHCI host controller maybe launch a TIMEOUT
interrupt before the erase cmd finishing. To avoid this kind of
situation, SDHCI HD need to calculate a correct timeout value
before issuing erase cmd. Patch added a routine to implement
this.

Signed-off-by: Chuanxiao Dong <[email protected]>
---
 drivers/mmc/core/core.c  |    4 ++++
 drivers/mmc/host/sdhci.c |   46 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 50 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index d464252..3df86c1 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -168,6 +168,9 @@ mmc_start_request(struct mmc_host *host, struct mmc_request 
*mrq)
 
        mrq->cmd->error = 0;
        mrq->cmd->mrq = mrq;
+       if (mrq->cmd->opcode != MMC_ERASE)
+               mrq->cmd->erase_timeout = 0;
+
        if (mrq->data) {
                BUG_ON(mrq->data->blksz > host->max_blk_size);
                BUG_ON(mrq->data->blocks > host->max_blk_count);
@@ -188,6 +191,7 @@ mmc_start_request(struct mmc_host *host, struct mmc_request 
*mrq)
                        mrq->data->stop = mrq->stop;
                        mrq->stop->error = 0;
                        mrq->stop->mrq = mrq;
+                       mrq->stop->erase_timeout = 0;
                }
        }
        host->ops->request(host, mrq);
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index f6a2b8a..f855efc 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -927,6 +927,48 @@ static void sdhci_clock_reset(struct sdhci_host *host)
        }
 }
 
+static void sdhci_set_erasetimeout(struct sdhci_host *host,
+               unsigned int erase_timeout)
+{
+       u64 current_timeout;
+       int count = 0xe;
+       /*
+        * If the host controller provides us with an incorrect timeout
+        * value, just skip the check and use 0xE.  The hardware may take
+        * longer to time out, but that's much better than having a too-short
+        * timeout value.
+        */
+       if (host->quirks & SDHCI_QUIRK_BROKEN_TIMEOUT_VAL)
+               goto out;
+
+       if (host->quirks & SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK)
+               host->timeout_clk = host->clock / 1000;
+
+       /* Caculate the MAX timeout time for host controller */
+
+       /* Timeout in ms */
+       count = 0xe;
+       current_timeout = (1 << 27) / host->timeout_clk;
+       while (current_timeout > erase_timeout) {
+               current_timeout >>= 1;
+               count--;
+               if (count == 0)
+                       break;
+       }
+
+       if (count == 0xe) {
+               /* host controller should disable timeout interrupt
+                * here. But right now some host controller timeout
+                * interrupt cannot be disabled
+                * */
+               pr_warn("warning: device may have not enough time "
+                               "to wait for erase cmd finishing\n");
+       } else
+               count += 1;
+out:
+       sdhci_writeb(host, count, SDHCI_TIMEOUT_CONTROL);
+}
+
 static void sdhci_send_command(struct sdhci_host *host, struct mmc_command 
*cmd)
 {
        int flags;
@@ -997,6 +1039,9 @@ static void sdhci_send_command(struct sdhci_host *host, 
struct mmc_command *cmd)
        if (host->quirks & SDHCI_QUIRK_SERIALIZE)
                sdhci_clock_reset(host);
 
+       if (cmd->erase_timeout)
+               sdhci_set_erasetimeout(host, cmd->erase_timeout);
+
        sdhci_writew(host, SDHCI_MAKE_CMD(cmd->opcode, flags), SDHCI_COMMAND);
 }
 
@@ -1943,6 +1988,7 @@ int sdhci_add_host(struct sdhci_host *host)
                mmc->f_min = host->max_clk / SDHCI_MAX_DIV_SPEC_200;
        mmc->f_max = host->max_clk;
        mmc->caps |= MMC_CAP_SDIO_IRQ;
+       mmc->caps |= MMC_CAP_ERASE;
 
        if (!(host->quirks & SDHCI_QUIRK_FORCE_1_BIT_DATA))
                mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA;
-- 
1.6.6.1

_______________________________________________
MeeGo-kernel mailing list
[email protected]
http://lists.meego.com/listinfo/meego-kernel

Reply via email to