[PATCH v4 1/2] mmc: core: Add packed command feature of eMMC4.5

From: Seungwon Jeon
Date: Thu Jan 26 2012 - 04:08:14 EST


This patch adds packed command feature of eMMC4.5.
The maximum number for packing read(or write) is offered
and exception event relevant to packed command which is
used for error handling is enabled. If host wants to use
this feature, MMC_CAP2_PACKED_CMD should be set.

Signed-off-by: Seungwon Jeon <tgih.jun@xxxxxxxxxxx>
---
drivers/mmc/core/mmc.c | 24 ++++++++++++++++++++++++
include/linux/mmc/card.h | 3 +++
include/linux/mmc/host.h | 1 +
include/linux/mmc/mmc.h | 15 +++++++++++++++
4 files changed, 43 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index dc03291..a7a46fa 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -533,6 +533,11 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd)
} else {
card->ext_csd.data_tag_unit_size = 0;
}
+
+ card->ext_csd.max_packed_writes =
+ ext_csd[EXT_CSD_MAX_PACKED_WRITES];
+ card->ext_csd.max_packed_reads =
+ ext_csd[EXT_CSD_MAX_PACKED_READS];
}

out:
@@ -1254,6 +1259,25 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
}
}

+ if ((host->caps2 & MMC_CAP2_PACKED_CMD) &&
+ (card->ext_csd.max_packed_writes > 0) &&
+ (card->ext_csd.max_packed_reads > 0)) {
+ err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
+ EXT_CSD_EXP_EVENTS_CTRL,
+ EXT_CSD_PACKED_EVENT_EN,
+ card->ext_csd.generic_cmd6_time);
+ if (err && err != -EBADMSG)
+ goto free_card;
+ if (err) {
+ pr_warning("%s: Enabling packed event failed\n",
+ mmc_hostname(card->host));
+ card->ext_csd.packed_event_en = 0;
+ err = 0;
+ } else {
+ card->ext_csd.packed_event_en = 1;
+ }
+ }
+
if (!oldcard)
host->card = card;

diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index f9a0663..2aa9f30 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -52,6 +52,9 @@ struct mmc_ext_csd {
u8 part_config;
u8 cache_ctrl;
u8 rst_n_function;
+ u8 max_packed_writes;
+ u8 max_packed_reads;
+ u8 packed_event_en;
unsigned int part_time; /* Units: ms */
unsigned int sa_timeout; /* Units: 100ns */
unsigned int generic_cmd6_time; /* Units: 10ms */
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index dd13e05..e22f541 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -257,6 +257,7 @@ struct mmc_host {
#define MMC_CAP2_HS200_1_2V_SDR (1 << 6) /* can support */
#define MMC_CAP2_HS200 (MMC_CAP2_HS200_1_8V_SDR | \
MMC_CAP2_HS200_1_2V_SDR)
+#define MMC_CAP2_PACKED_CMD (1 << 7) /* Allow packed command */

mmc_pm_flag_t pm_caps; /* supported pm features */
unsigned int power_notify_type;
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index b822a2c..d990760 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -139,6 +139,7 @@ static inline bool mmc_op_multi(u32 opcode)
#define R1_CURRENT_STATE(x) ((x & 0x00001E00) >> 9) /* sx, b (4 bits) */
#define R1_READY_FOR_DATA (1 << 8) /* sx, a */
#define R1_SWITCH_ERROR (1 << 7) /* sx, c */
+#define R1_EXP_EVENT (1 << 6) /* sr, a */
#define R1_APP_CMD (1 << 5) /* sr, c */

#define R1_STATE_IDLE 0
@@ -274,6 +275,10 @@ struct _mmc_csd {
#define EXT_CSD_FLUSH_CACHE 32 /* W */
#define EXT_CSD_CACHE_CTRL 33 /* R/W */
#define EXT_CSD_POWER_OFF_NOTIFICATION 34 /* R/W */
+#define EXT_CSD_PACKED_FAILURE_INDEX 35 /* RO */
+#define EXT_CSD_PACKED_CMD_STATUS 36 /* RO */
+#define EXT_CSD_EXP_EVENTS_STATUS 54 /* RO, 2 bytes */
+#define EXT_CSD_EXP_EVENTS_CTRL 56 /* R/W, 2 bytes */
#define EXT_CSD_DATA_SECTOR_SIZE 61 /* R */
#define EXT_CSD_GP_SIZE_MULT 143 /* R/W */
#define EXT_CSD_PARTITION_ATTRIBUTE 156 /* R/W */
@@ -318,6 +323,8 @@ struct _mmc_csd {
#define EXT_CSD_CACHE_SIZE 249 /* RO, 4 bytes */
#define EXT_CSD_TAG_UNIT_SIZE 498 /* RO */
#define EXT_CSD_DATA_TAG_SUPPORT 499 /* RO */
+#define EXT_CSD_MAX_PACKED_WRITES 500 /* RO */
+#define EXT_CSD_MAX_PACKED_READS 501 /* RO */
#define EXT_CSD_HPI_FEATURES 503 /* RO */

/*
@@ -437,6 +444,14 @@ struct _mmc_csd {
#define EXT_CSD_PWR_CL_4BIT_MASK 0x0F /* 8 bit PWR CLS */
#define EXT_CSD_PWR_CL_8BIT_SHIFT 4
#define EXT_CSD_PWR_CL_4BIT_SHIFT 0
+
+#define EXT_CSD_PACKED_EVENT_EN (1 << 3)
+
+#define EXT_CSD_PACKED_FAILURE (1 << 3)
+
+#define EXT_CSD_PACKED_GENERIC_ERROR (1 << 0)
+#define EXT_CSD_PACKED_INDEXED_ERROR (1 << 1)
+
/*
* MMC_SWITCH access modes
*/
--
1.7.0.4


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