Host Controller v3.00 and later support Auto CMD23 in the Transfer
Mode register. Since Auto CMD23 can be used with or without DMA,
and if used with DMA, it should _only_ be ADMA, we check against
SDHCI_USE_SDMA not being set. This flag is reset when SDHCI_USE_ADMA
is set.

A new definition for SDHCI_ARGUMENT2 register has been added in v3.00
spec, which is the same as SDHCI_DMA_ADDRESS. We program the block
count for CMD23 in SDHCI_ARGUMENT2, so we don't need CMD12 to stop
multiple block transfers. But during error recovery procedure, we will
need to send Abort command, so we use a variable saved_abort_cmd to
save the stop command to be used later.

Signed-off-by: Arindam Nath <arindam.n...@amd.com>
---
 drivers/mmc/core/sd.c     |    6 ++++
 drivers/mmc/host/sdhci.c  |   71 +++++++++++++++++++++++++++++++++++++++++---
 drivers/mmc/host/sdhci.h  |    2 +
 include/linux/mmc/card.h  |    4 ++
 include/linux/mmc/sd.h    |    2 +-
 include/linux/mmc/sdhci.h |    2 +
 6 files changed, 81 insertions(+), 6 deletions(-)

diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index 6dac89f..460ec24 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -189,6 +189,12 @@ static int mmc_decode_scr(struct mmc_card *card)
 
        scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4);
        scr->bus_widths = UNSTUFF_BITS(resp, 48, 4);
+       if (scr->sda_vsn == SCR_SPEC_VER_2) {
+               /* Check if Physical Layer Spec v3.0 is supported*/
+               scr->sda_spec3 = UNSTUFF_BITS(resp, 47, 1);
+               if (scr->sda_spec3)
+                       scr->cmd_support = UNSTUFF_BITS(resp, 32, 2);
+       }
 
        if (UNSTUFF_BITS(resp, 55, 1))
                card->erased_byte = 0xFF;
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 94793f2..7921ced 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -25,6 +25,7 @@
 
 #include <linux/mmc/mmc.h>
 #include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
 
 #include "sdhci.h"
 
@@ -821,6 +822,30 @@ static void sdhci_prepare_data(struct sdhci_host *host, 
struct mmc_command *cmd)
        sdhci_writew(host, data->blocks, SDHCI_BLOCK_COUNT);
 }
 
+/*
+ * Does the Host Controller support Auto CMD23?
+ *
+ * There are four preconditions for Auto CMD23 to be supported:
+ *  1. Host Controller v3.00 or later
+ *  2. Card supports CMD23
+ *  3. If DMA is used, it should be ADMA
+ *  4. Only when CMD18 or CMD25 is issued
+ */
+static int sdhci_host_auto_cmd23_required(struct sdhci_host *host,
+       struct mmc_request *mrq)
+{
+       struct mmc_card *card = host->mmc->card;
+
+       if ((host->version >= SDHCI_SPEC_300) &&
+          card && (card->scr.cmd_support & SD_SCR_CMD23_SUPPORT) &&
+          !(host->flags & SDHCI_USE_SDMA) &&
+          ((mrq->cmd->opcode == MMC_READ_MULTIPLE_BLOCK) ||
+          (mrq->cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK)))
+               return 1;
+
+       return 0;
+}
+
 static void sdhci_set_transfer_mode(struct sdhci_host *host,
        struct mmc_data *data)
 {
@@ -834,10 +859,21 @@ static void sdhci_set_transfer_mode(struct sdhci_host 
*host,
        mode = SDHCI_TRNS_BLK_CNT_EN;
        if (data->blocks > 1) {
                if (host->quirks & SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12)
-                       mode |= SDHCI_TRNS_MULTI | SDHCI_TRNS_ACMD12;
-               else
-                       mode |= SDHCI_TRNS_MULTI;
+                       mode |= SDHCI_TRNS_ACMD12;
+               else if (sdhci_host_auto_cmd23_required(host, host->mrq)) {
+                       /*
+                        * Host Controller v3.00 can automatically send CMD23
+                        * before CMD18 or CMD25. For that, we need to enable
+                        * Auto CMD23 in the Transfer Mode register and
+                        * program the block count in Argument 2 register.
+                        */
+                       mode |= SDHCI_TRNS_AUTO_CMD23;
+                       sdhci_writel(host, data->blocks, SDHCI_ARGUMENT2);
+               }
+
+               mode |= SDHCI_TRNS_MULTI;
        }
+
        if (data->flags & MMC_DATA_READ)
                mode |= SDHCI_TRNS_READ;
        if (host->flags & SDHCI_REQ_USE_DMA)
@@ -1140,6 +1176,23 @@ static void sdhci_request(struct mmc_host *mmc, struct 
mmc_request *mrq)
 #ifndef SDHCI_USE_LEDS_CLASS
        sdhci_activate_led(host);
 #endif
+       /*
+        * Since the block count for CMD23 has already been specified in the
+        * Argument 2 register, we don't need CMD12 to stop multiple block
+        * transfers.
+        */
+       if (sdhci_host_auto_cmd23_required(host, mrq)) {
+               if (mrq->stop) {
+                       /*
+                        * Save the stop command here to be used during
+                        * error recovery
+                        */
+                       host->saved_abort_cmd = mrq->data->stop;
+                       mrq->data->stop = NULL;
+                       mrq->stop = NULL;
+               }
+       }
+
        if (host->quirks & SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12) {
                if (mrq->stop) {
                        mrq->data->stop = NULL;
@@ -1405,6 +1458,8 @@ static void sdhci_timeout_timer(unsigned long data)
 
                if (host->data) {
                        host->data->error = -ETIMEDOUT;
+                       if (host->saved_abort_cmd)
+                               host->data->stop = host->saved_abort_cmd;
                        sdhci_finish_data(host);
                } else {
                        if (host->cmd)
@@ -1543,9 +1598,11 @@ static void sdhci_data_irq(struct sdhci_host *host, u32 
intmask)
                host->data->error = -EIO;
        }
 
-       if (host->data->error)
+       if (host->data->error) {
+               if (host->saved_abort_cmd)
+                       host->data->stop = host->saved_abort_cmd;
                sdhci_finish_data(host);
-       else {
+       } else {
                if (intmask & (SDHCI_INT_DATA_AVAIL | SDHCI_INT_SPACE_AVAIL))
                        sdhci_transfer_pio(host);
 
@@ -1819,6 +1876,10 @@ int sdhci_add_host(struct sdhci_host *host)
                host->flags &= ~SDHCI_USE_ADMA;
        }
 
+       /* If the host can perform ADMA operation, we reset SDMA flag */
+       if (host->flags & SDHCI_USE_ADMA)
+               host->flags &= ~SDHCI_USE_SDMA;
+
        if (host->flags & (SDHCI_USE_SDMA | SDHCI_USE_ADMA)) {
                if (host->ops->enable_dma) {
                        if (host->ops->enable_dma(host)) {
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 85750a9..9f8575e 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -25,6 +25,7 @@
  */
 
 #define SDHCI_DMA_ADDRESS      0x00
+#define SDHCI_ARGUMENT2                SDHCI_DMA_ADDRESS
 
 #define SDHCI_BLOCK_SIZE       0x04
 #define  SDHCI_MAKE_BLKSZ(dma, blksz) (((dma & 0x7) << 12) | (blksz & 0xFFF))
@@ -37,6 +38,7 @@
 #define  SDHCI_TRNS_DMA                0x01
 #define  SDHCI_TRNS_BLK_CNT_EN 0x02
 #define  SDHCI_TRNS_ACMD12     0x04
+#define  SDHCI_TRNS_AUTO_CMD23 0x08
 #define  SDHCI_TRNS_READ       0x10
 #define  SDHCI_TRNS_MULTI      0x20
 
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 72a9868..86d9672 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -67,9 +67,13 @@ struct mmc_ext_csd {
 
 struct sd_scr {
        unsigned char           sda_vsn;
+       unsigned char           sda_spec3;
        unsigned char           bus_widths;
 #define SD_SCR_BUS_WIDTH_1     (1<<0)
 #define SD_SCR_BUS_WIDTH_4     (1<<2)
+       unsigned char           cmd_support;
+#define SD_SCR_CMD20_SUPPORT   (1<<0)
+#define SD_SCR_CMD23_SUPPORT   (1<<1)
 };
 
 struct sd_ssr {
diff --git a/include/linux/mmc/sd.h b/include/linux/mmc/sd.h
index 3fd85e0..178363b 100644
--- a/include/linux/mmc/sd.h
+++ b/include/linux/mmc/sd.h
@@ -59,7 +59,7 @@
 
 #define SCR_SPEC_VER_0         0       /* Implements system specification 1.0 
- 1.01 */
 #define SCR_SPEC_VER_1         1       /* Implements system specification 1.10 
*/
-#define SCR_SPEC_VER_2         2       /* Implements system specification 2.00 
*/
+#define SCR_SPEC_VER_2         2       /* Implements system specification 2.00 
- 3.0x */
 
 /*
  * SD bus widths
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index 83bd9f7..282d158 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -145,6 +145,8 @@ struct sdhci_host {
        unsigned int            ocr_avail_sd;
        unsigned int            ocr_avail_mmc;
 
+       struct mmc_command      *saved_abort_cmd; /* Abort command saved for 
data error recovery */
+
        unsigned long private[0] ____cacheline_aligned;
 };
 #endif /* __SDHCI_H */
-- 
1.7.1

--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to