[PATCH 0/5] mmc: add eMMC hardware reset support

[PATCH 0/5] mmc: add eMMC hardware reset support

[Adrian Hunter]

Hi

Here are some patches to add eMMC hardware reset support.

Adrian Hunter (5):
      mmc: add eMMC hardware reset support
      mmc: sdhci: add eMMC hardware reset support
      mmc: sdhci-pci: add eMMC hardware reset support
      mmc: mmc-test: add eMMC hardware reset test
      mmc: block: add eMMC hardware reset support

 drivers/mmc/card/block.c     |  201 +++++++++++++++++++++++++++++------------
 drivers/mmc/card/mmc_test.c  |   30 ++++++
 drivers/mmc/core/core.c      |   99 ++++++++++++++++++++-
 drivers/mmc/core/mmc.c       |    4 +-
 drivers/mmc/host/sdhci-pci.c |   72 +++++++++++++++
 drivers/mmc/host/sdhci.c     |    9 ++
 drivers/mmc/host/sdhci.h     |    2 +-
 include/linux/mmc/card.h     |    1 +
 include/linux/mmc/core.h     |    3 +
 include/linux/mmc/host.h     |    2 +
 include/linux/mmc/mmc.h      |    4 +
 11 files changed, 364 insertions(+), 63 deletions(-)

Regards
Adrian Hunter

[PATCH 1/5] mmc: add eMMC hardware reset support

[Adrian Hunter]

eMMC's may have a hardware reset line.  This patch provides a
host controller operation to implement hardware reset and
a function to reset and reinitialize the card.  Also, for MMC,
the reset is always performed before initialization.

The host must set the new host capability MMC_CAP_HW_RESET
to enable hardware reset.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 drivers/mmc/core/core.c  |   95 ++++++++++++++++++++++++++++++++++++++++++++++
 drivers/mmc/core/mmc.c   |    4 +-
 include/linux/mmc/card.h |    1 +
 include/linux/mmc/core.h |    3 +
 include/linux/mmc/host.h |    2 +
 include/linux/mmc/mmc.h  |    4 ++
 6 files changed, 108 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 557856b..3bdb981 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1768,6 +1768,95 @@ int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
 }
 EXPORT_SYMBOL(mmc_set_blocklen);
 
+static void mmc_hw_reset_for_init(struct mmc_host *host)
+{
+	if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
+		return;
+	mmc_host_clk_hold(host);
+	host->ops->hw_reset(host);
+	mmc_host_clk_release(host);
+}
+
+int mmc_can_reset(struct mmc_card *card)
+{
+	u8 rst_n_function;
+
+	if (!mmc_card_mmc(card))
+		return 0;
+	rst_n_function = card->ext_csd.rst_n_function;
+	if ((rst_n_function & EXT_CSD_RST_N_EN_MASK) != EXT_CSD_RST_N_ENABLED)
+		return 0;
+	return 1;
+}
+EXPORT_SYMBOL(mmc_can_reset);
+
+static int mmc_do_hw_reset(struct mmc_host *host, int check)
+{
+	struct mmc_card *card = host->card;
+
+	if (!host->bus_ops->power_restore)
+		return -EOPNOTSUPP;
+
+	if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
+		return -EOPNOTSUPP;
+
+	if (!card)
+		return -EINVAL;
+
+	if (!mmc_can_reset(card))
+		return -EOPNOTSUPP;
+
+	mmc_host_clk_hold(host);
+	mmc_set_clock(host, host->f_init);
+
+	host->ops->hw_reset(host);
+
+	/* If the reset has happened, then a status command will fail */
+	if (check) {
+		struct mmc_command cmd = {0};
+		int err;
+
+		cmd.opcode = MMC_SEND_STATUS;
+		if (!mmc_host_is_spi(card->host))
+			cmd.arg = card->rca << 16;
+		cmd.flags = MMC_RSP_SPI_R2 | MMC_RSP_R1 | MMC_CMD_AC;
+		err = mmc_wait_for_cmd(card->host, &cmd, 0);
+		if (!err) {
+			mmc_host_clk_release(host);
+			return -ENOSYS;
+		}
+	}
+
+	host->card->state &= ~(MMC_STATE_HIGHSPEED | MMC_STATE_HIGHSPEED_DDR);
+	if (mmc_host_is_spi(host)) {
+		host->ios.chip_select = MMC_CS_HIGH;
+		host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
+	} else {
+		host->ios.chip_select = MMC_CS_DONTCARE;
+		host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
+	}
+	host->ios.bus_width = MMC_BUS_WIDTH_1;
+	host->ios.timing = MMC_TIMING_LEGACY;
+	host->ios.ddr = MMC_SDR_MODE;
+	mmc_set_ios(host);
+
+	mmc_host_clk_release(host);
+
+	return host->bus_ops->power_restore(host);
+}
+
+int mmc_hw_reset(struct mmc_host *host)
+{
+	return mmc_do_hw_reset(host, 0);
+}
+EXPORT_SYMBOL(mmc_hw_reset);
+
+int mmc_hw_reset_check(struct mmc_host *host)
+{
+	return mmc_do_hw_reset(host, 1);
+}
+EXPORT_SYMBOL(mmc_hw_reset_check);
+
 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 {
 	host->f_init = freq;
@@ -1779,6 +1868,12 @@ static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 	mmc_power_up(host);
 
 	/*
+	 * Some eMMCs (with VCCQ always on) may not be reset after power up, so
+	 * do a hardware reset if possible.
+	 */
+	mmc_hw_reset_for_init(host);
+
+	/*
 	 * sdio_reset sends CMD52 to reset card.  Since we do not know
 	 * if the card is being re-initialized, just send it.  CMD52
 	 * should be ignored by SD/eMMC cards.
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 5700b1c..e090a87 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -402,8 +402,10 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd)
 			ext_csd[EXT_CSD_TRIM_MULT];
 	}
 
-	if (card->ext_csd.rev >= 5)
+	if (card->ext_csd.rev >= 5) {
 		card->ext_csd.rel_param = ext_csd[EXT_CSD_WR_REL_PARAM];
+		card->ext_csd.rst_n_function = ext_csd[EXT_CSD_RST_N_FUNCTION];
+	}
 
 	if (ext_csd[EXT_CSD_ERASED_MEM_CONT])
 		card->erased_byte = 0xFF;
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index b460fc2..a45c5b8 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -50,6 +50,7 @@ struct mmc_ext_csd {
 	u8			rel_sectors;
 	u8			rel_param;
 	u8			part_config;
+	u8			rst_n_function;
 	unsigned int		part_time;		/* Units: ms */
 	unsigned int		sa_timeout;		/* Units: 100ns */
 	unsigned int		hs_max_dtr;
diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h
index b8b1b7a..56e5625 100644
--- a/include/linux/mmc/core.h
+++ b/include/linux/mmc/core.h
@@ -162,6 +162,9 @@ extern int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
 extern unsigned int mmc_calc_max_discard(struct mmc_card *card);
 
 extern int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen);
+extern int mmc_hw_reset(struct mmc_host *host);
+extern int mmc_hw_reset_check(struct mmc_host *host);
+extern int mmc_can_reset(struct mmc_card *card);
 
 extern void mmc_set_data_timeout(struct mmc_data *, const struct mmc_card *);
 extern unsigned int mmc_align_data_size(struct mmc_card *, unsigned int);
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 4c4bddf..85b5626 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -148,6 +148,7 @@ struct mmc_host_ops {
 	int	(*execute_tuning)(struct mmc_host *host);
 	void	(*enable_preset_value)(struct mmc_host *host, bool enable);
 	int	(*select_drive_strength)(unsigned int max_dtr, int host_drv, int card_drv);
+	void	(*hw_reset)(struct mmc_host *host);
 };
 
 struct mmc_card;
@@ -230,6 +231,7 @@ struct mmc_host {
 #define MMC_CAP_MAX_CURRENT_600	(1 << 28)	/* Host max current limit is 600mA */
 #define MMC_CAP_MAX_CURRENT_800	(1 << 29)	/* Host max current limit is 800mA */
 #define MMC_CAP_CMD23		(1 << 30)	/* CMD23 supported. */
+#define MMC_CAP_HW_RESET	(1 << 31)	/* Hardware reset */
 
 	mmc_pm_flag_t		pm_caps;	/* supported pm features */
 
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index 5a794cb..ed8fca8 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -272,6 +272,7 @@ struct _mmc_csd {
 
 #define EXT_CSD_PARTITION_ATTRIBUTE	156	/* R/W */
 #define EXT_CSD_PARTITION_SUPPORT	160	/* RO */
+#define EXT_CSD_RST_N_FUNCTION		162	/* R/W */
 #define EXT_CSD_WR_REL_PARAM		166	/* RO */
 #define EXT_CSD_ERASE_GROUP_DEF		175	/* R/W */
 #define EXT_CSD_PART_CONFIG		179	/* R/W */
@@ -328,6 +329,9 @@ struct _mmc_csd {
 #define EXT_CSD_SEC_BD_BLK_EN	BIT(2)
 #define EXT_CSD_SEC_GB_CL_EN	BIT(4)
 
+#define EXT_CSD_RST_N_EN_MASK	0x3
+#define EXT_CSD_RST_N_ENABLED	1	/* RST_n is enabled on card */
+
 /*
  * MMC_SWITCH access modes
  */
-- 
1.7.6

[PATCH 2/5] mmc: sdhci: add eMMC hardware reset support

[Adrian Hunter]

Add an SDHCI operation for hardware reset and connect it to the
host controller operation.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 drivers/mmc/host/sdhci.c |    9 +++++++++
 drivers/mmc/host/sdhci.h |    2 +-
 2 files changed, 10 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 0e02cc1..d66a7a1 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1471,6 +1471,14 @@ static int sdhci_get_ro(struct mmc_host *mmc)
 	return 0;
 }
 
+static void sdhci_hw_reset(struct mmc_host *mmc)
+{
+	struct sdhci_host *host = mmc_priv(mmc);
+
+	if (host->ops && host->ops->hw_reset)
+		host->ops->hw_reset(host);
+}
+
 static void sdhci_enable_sdio_irq(struct mmc_host *mmc, int enable)
 {
 	struct sdhci_host *host;
@@ -1805,6 +1813,7 @@ static const struct mmc_host_ops sdhci_ops = {
 	.request	= sdhci_request,
 	.set_ios	= sdhci_set_ios,
 	.get_ro		= sdhci_get_ro,
+	.hw_reset	= sdhci_hw_reset,
 	.enable_sdio_irq = sdhci_enable_sdio_irq,
 	.start_signal_voltage_switch	= sdhci_start_signal_voltage_switch,
 	.execute_tuning			= sdhci_execute_tuning,
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 745c42f..7bd919c 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -273,7 +273,7 @@ struct sdhci_ops {
 	void	(*platform_reset_enter)(struct sdhci_host *host, u8 mask);
 	void	(*platform_reset_exit)(struct sdhci_host *host, u8 mask);
 	int	(*set_uhs_signaling)(struct sdhci_host *host, unsigned int uhs);
-
+	void	(*hw_reset)(struct sdhci_host *host);
 };
 
 #ifdef CONFIG_MMC_SDHCI_IO_ACCESSORS
-- 
1.7.6

[PATCH 3/5] mmc: sdhci-pci: add eMMC hardware reset support

[Adrian Hunter]

Implement eMMC hardware reset for Medfield.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 drivers/mmc/host/sdhci-pci.c |   72 ++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 72 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
index 26c5286..3b30c51 100644
--- a/drivers/mmc/host/sdhci-pci.c
+++ b/drivers/mmc/host/sdhci-pci.c
@@ -21,6 +21,8 @@
 #include <linux/mmc/host.h>
 #include <linux/scatterlist.h>
 #include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/sfi.h>
 
 #include "sdhci.h"
 
@@ -59,6 +61,7 @@ struct sdhci_pci_slot {
 	struct sdhci_host	*host;
 
 	int			pci_bar;
+	int			rst_n_gpio;
 };
 
 struct sdhci_pci_chip {
@@ -163,12 +166,63 @@ static int mrst_hc_probe(struct sdhci_pci_chip *chip)
 	return 0;
 }
 
+/* Medfield eMMC hardware reset GPIOs */
+static int mfd_emmc0_rst_gpio = -EINVAL;
+static int mfd_emmc1_rst_gpio = -EINVAL;
+
+static int mfd_emmc_gpio_parse(struct sfi_table_header *table)
+{
+	struct sfi_table_simple *sb = (struct sfi_table_simple *)table;
+	struct sfi_gpio_table_entry *entry;
+	int i, num;
+
+	num = SFI_GET_NUM_ENTRIES(sb, struct sfi_gpio_table_entry);
+	entry = (struct sfi_gpio_table_entry *)sb->pentry;
+
+	for (i = 0; i < num; i++, entry++) {
+		if (!strncmp(entry->pin_name, "emmc0_rst", SFI_NAME_LEN))
+			mfd_emmc0_rst_gpio = entry->pin_no;
+		else if (!strncmp(entry->pin_name, "emmc1_rst", SFI_NAME_LEN))
+			mfd_emmc1_rst_gpio = entry->pin_no;
+	}
+
+	return 0;
+}
+
 static int mfd_emmc_probe_slot(struct sdhci_pci_slot *slot)
 {
+	const char *name = NULL;
+	int gpio = -EINVAL;
+
+	sfi_table_parse(SFI_SIG_GPIO, NULL, NULL, mfd_emmc_gpio_parse);
+
+	switch (slot->chip->pdev->device) {
+	case PCI_DEVICE_ID_INTEL_MFD_EMMC0:
+		gpio = mfd_emmc0_rst_gpio;
+		name = "eMMC0_reset";
+		break;
+	case PCI_DEVICE_ID_INTEL_MFD_EMMC1:
+		gpio = mfd_emmc1_rst_gpio;
+		name = "eMMC1_reset";
+		break;
+	}
+
+	if (!gpio_request(gpio, name)) {
+		gpio_direction_output(gpio, 1);
+		slot->rst_n_gpio = gpio;
+		slot->host->mmc->caps |= MMC_CAP_HW_RESET;
+	}
+
 	slot->host->mmc->caps |= MMC_CAP_8_BIT_DATA;
+
 	return 0;
 }
 
+static void mfd_emmc_remove_slot(struct sdhci_pci_slot *slot, int dead)
+{
+	gpio_free(slot->rst_n_gpio);
+}
+
 static const struct sdhci_pci_fixes sdhci_intel_mrst_hc0 = {
 	.quirks		= SDHCI_QUIRK_BROKEN_ADMA | SDHCI_QUIRK_NO_HISPD_BIT,
 	.probe_slot	= mrst_hc_probe_slot,
@@ -190,6 +244,7 @@ static const struct sdhci_pci_fixes sdhci_intel_mfd_sdio = {
 static const struct sdhci_pci_fixes sdhci_intel_mfd_emmc = {
 	.quirks		= SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC,
 	.probe_slot	= mfd_emmc_probe_slot,
+	.remove_slot	= mfd_emmc_remove_slot,
 };
 
 /* O2Micro extra registers */
@@ -832,9 +887,25 @@ static int sdhci_pci_8bit_width(struct sdhci_host *host, int width)
 	return 0;
 }
 
+static void sdhci_pci_hw_reset(struct sdhci_host *host)
+{
+	struct sdhci_pci_slot *slot = sdhci_priv(host);
+	int rst_n_gpio = slot->rst_n_gpio;
+
+	if (!gpio_is_valid(rst_n_gpio))
+		return;
+	gpio_set_value_cansleep(rst_n_gpio, 0);
+	/* For eMMC, minimum is 1us but give it 10us for good measure */
+	udelay(10);
+	gpio_set_value_cansleep(rst_n_gpio, 1);
+	/* For eMMC, minimum is 200us but give it 300us for good measure */
+	usleep_range(300, 1000);
+}
+
 static struct sdhci_ops sdhci_pci_ops = {
 	.enable_dma	= sdhci_pci_enable_dma,
 	.platform_8bit_width	= sdhci_pci_8bit_width,
+	.hw_reset		= sdhci_pci_hw_reset,
 };
 
 /*****************************************************************************\
@@ -988,6 +1059,7 @@ static struct sdhci_pci_slot * __devinit sdhci_pci_probe_slot(
 	slot->chip = chip;
 	slot->host = host;
 	slot->pci_bar = bar;
+	slot->rst_n_gpio = -EINVAL;
 
 	host->hw_name = "PCI";
 	host->ops = &sdhci_pci_ops;
-- 
1.7.6

[PATCH 4/5] mmc: mmc-test: add eMMC hardware reset test

[Adrian Hunter]

MMC core provides a checking function that checks if the reset
has happended.  Add a test to use that function.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 drivers/mmc/card/mmc_test.c |   30 ++++++++++++++++++++++++++++++
 1 files changed, 30 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/card/mmc_test.c b/drivers/mmc/card/mmc_test.c
index 2bf229a..9cdce63 100644
--- a/drivers/mmc/card/mmc_test.c
+++ b/drivers/mmc/card/mmc_test.c
@@ -2328,6 +2328,31 @@ static int mmc_test_profile_sglen_r_nonblock_perf(struct mmc_test_card *test)
 	return mmc_test_rw_multiple_sg_len(test, &test_data);
 }
 
+/*
+ * eMMC hardware reset.
+ */
+static int mmc_test_hw_reset(struct mmc_test_card *test)
+{
+	struct mmc_card *card = test->card;
+	struct mmc_host *host = card->host;
+	int err;
+
+	err = mmc_hw_reset_check(host);
+	if (!err)
+		return RESULT_OK;
+
+	if (err == -ENOSYS)
+		return RESULT_FAIL;
+
+	if (err != -EOPNOTSUPP)
+		return err;
+
+	if (!mmc_can_reset(card))
+		return RESULT_UNSUP_CARD;
+
+	return RESULT_UNSUP_HOST;
+}
+
 static const struct mmc_test_case mmc_test_cases[] = {
 	{
 		.name = "Basic write (no data verification)",
@@ -2650,6 +2675,11 @@ static const struct mmc_test_case mmc_test_cases[] = {
 		.run = mmc_test_profile_sglen_r_nonblock_perf,
 		.cleanup = mmc_test_area_cleanup,
 	},
+
+	{
+		.name = "eMMC hardware reset",
+		.run = mmc_test_hw_reset,
+	},
 };
 
 static DEFINE_MUTEX(mmc_test_lock);
-- 
1.7.6

[PATCH 5/5] mmc: block: add eMMC hardware reset support

[Adrian Hunter]

For cards that support hardware reset (just eMMC), try a reset and
retry before returning an I/O error.  However this is not done for
ECC errors and is never done twice for the same operation type
(READ, WRITE, DISCARD, SECURE DISCARD) until that type of operation
again succeeds.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 drivers/mmc/card/block.c |  201 ++++++++++++++++++++++++++++++++--------------
 drivers/mmc/core/core.c  |    4 +-
 2 files changed, 144 insertions(+), 61 deletions(-)

diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index e702c61..2a05b24 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -94,6 +94,11 @@ struct mmc_blk_data {
 	unsigned int	read_only;
 	unsigned int	part_type;
 	unsigned int	name_idx;
+	unsigned int	reset_done;
+#define MMC_BLK_READ		BIT(0)
+#define MMC_BLK_WRITE		BIT(1)
+#define MMC_BLK_DISCARD		BIT(2)
+#define MMC_BLK_SECDISCARD	BIT(3)
 
 	/*
 	 * Only set in main mmc_blk_data associated
@@ -109,11 +114,11 @@ static DEFINE_MUTEX(open_lock);
 enum mmc_blk_status {
 	MMC_BLK_SUCCESS = 0,
 	MMC_BLK_PARTIAL,
-	MMC_BLK_RETRY,
-	MMC_BLK_RETRY_SINGLE,
-	MMC_BLK_DATA_ERR,
 	MMC_BLK_CMD_ERR,
+	MMC_BLK_RETRY,
 	MMC_BLK_ABORT,
+	MMC_BLK_DATA_ERR,
+	MMC_BLK_ECC_ERR,
 };
 
 module_param(perdev_minors, int, 0444);
@@ -454,7 +459,7 @@ static inline int mmc_blk_part_switch(struct mmc_card *card,
 				 card->ext_csd.part_time);
 		if (ret)
 			return ret;
-}
+	}
 
 	main_md->part_curr = md->part_type;
 	return 0;
@@ -616,7 +621,7 @@ static int mmc_blk_cmd_error(struct request *req, const char *name, int error,
  * Otherwise we don't understand what happened, so abort.
  */
 static int mmc_blk_cmd_recovery(struct mmc_card *card, struct request *req,
-	struct mmc_blk_request *brq)
+	struct mmc_blk_request *brq, int *ecc_err)
 {
 	bool prev_cmd_status_valid = true;
 	u32 status, stop_status = 0;
@@ -641,6 +646,12 @@ static int mmc_blk_cmd_recovery(struct mmc_card *card, struct request *req,
 	if (err)
 		return ERR_ABORT;
 
+	/* Flag ECC errors */
+	if ((status & R1_CARD_ECC_FAILED) ||
+	    (brq->stop.resp[0] & R1_CARD_ECC_FAILED) ||
+	    (brq->cmd.resp[0] & R1_CARD_ECC_FAILED))
+		*ecc_err = 1;
+
 	/*
 	 * Check the current card state.  If it is in some data transfer
 	 * mode, tell it to stop (and hopefully transition back to TRAN.)
@@ -658,6 +669,8 @@ static int mmc_blk_cmd_recovery(struct mmc_card *card, struct request *req,
 		 */
 		if (err)
 			return ERR_ABORT;
+		if (stop_status & R1_CARD_ECC_FAILED)
+			*ecc_err = 1;
 	}
 
 	/* Check for set block count errors */
@@ -670,6 +683,10 @@ static int mmc_blk_cmd_recovery(struct mmc_card *card, struct request *req,
 		return mmc_blk_cmd_error(req, "r/w cmd", brq->cmd.error,
 				prev_cmd_status_valid, status);
 
+	/* Data errors */
+	if (!brq->stop.error)
+		return ERR_CONTINUE;
+
 	/* Now for stop errors.  These aren't fatal to the transfer. */
 	pr_err("%s: error %d sending stop command, original cmd response %#x, card status %#x\n",
 	       req->rq_disk->disk_name, brq->stop.error,
@@ -686,12 +703,45 @@ static int mmc_blk_cmd_recovery(struct mmc_card *card, struct request *req,
 	return ERR_CONTINUE;
 }
 
+static int mmc_blk_reset(struct mmc_blk_data *md, struct mmc_host *host,
+			 int type)
+{
+	int err;
+
+	if (md->reset_done & type)
+		return -EEXIST;
+
+	md->reset_done |= type;
+	err = mmc_hw_reset(host);
+	/* Ensure we switch back to the correct partition */
+	if (err != -EOPNOTSUPP) {
+		struct mmc_blk_data *main_md = mmc_get_drvdata(host->card);
+		int part_err;
+
+		main_md->part_curr = main_md->part_type;
+		part_err = mmc_blk_part_switch(host->card, md);
+		if (part_err) {
+			/*
+			 * We have failed to get back into the correct
+			 * partition, so we need to abort the whole request.
+			 */
+			return -ENODEV;
+		}
+	}
+	return err;
+}
+
+static inline void mmc_blk_reset_success(struct mmc_blk_data *md, int type)
+{
+	md->reset_done &= ~type;
+}
+
 static int mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct request *req)
 {
 	struct mmc_blk_data *md = mq->data;
 	struct mmc_card *card = md->queue.card;
 	unsigned int from, nr, arg;
-	int err = 0;
+	int err = 0, type = MMC_BLK_DISCARD;
 
 	if (!mmc_can_erase(card)) {
 		err = -EOPNOTSUPP;
@@ -705,7 +755,7 @@ static int mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct request *req)
 		arg = MMC_TRIM_ARG;
 	else
 		arg = MMC_ERASE_ARG;
-
+retry:
 	if (card->quirks & MMC_QUIRK_INAND_CMD38) {
 		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
 				 INAND_CMD38_ARG_EXT_CSD,
@@ -718,6 +768,10 @@ static int mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct request *req)
 	}
 	err = mmc_erase(card, from, nr, arg);
 out:
+	if (err == -EIO && !mmc_blk_reset(md, card->host, type))
+		goto retry;
+	if (!err)
+		mmc_blk_reset_success(md, type);
 	spin_lock_irq(&md->lock);
 	__blk_end_request(req, err, blk_rq_bytes(req));
 	spin_unlock_irq(&md->lock);
@@ -731,7 +785,7 @@ static int mmc_blk_issue_secdiscard_rq(struct mmc_queue *mq,
 	struct mmc_blk_data *md = mq->data;
 	struct mmc_card *card = md->queue.card;
 	unsigned int from, nr, arg;
-	int err = 0;
+	int err = 0, type = MMC_BLK_SECDISCARD;
 
 	if (!mmc_can_secure_erase_trim(card)) {
 		err = -EOPNOTSUPP;
@@ -745,7 +799,7 @@ static int mmc_blk_issue_secdiscard_rq(struct mmc_queue *mq,
 		arg = MMC_SECURE_TRIM1_ARG;
 	else
 		arg = MMC_SECURE_ERASE_ARG;
-
+retry:
 	if (card->quirks & MMC_QUIRK_INAND_CMD38) {
 		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
 				 INAND_CMD38_ARG_EXT_CSD,
@@ -769,6 +823,10 @@ static int mmc_blk_issue_secdiscard_rq(struct mmc_queue *mq,
 		err = mmc_erase(card, from, nr, MMC_SECURE_TRIM2_ARG);
 	}
 out:
+	if (err == -EIO && !mmc_blk_reset(md, card->host, type))
+		goto retry;
+	if (!err)
+		mmc_blk_reset_success(md, type);
 	spin_lock_irq(&md->lock);
 	__blk_end_request(req, err, blk_rq_bytes(req));
 	spin_unlock_irq(&md->lock);
@@ -825,11 +883,11 @@ static inline void mmc_apply_rel_rw(struct mmc_blk_request *brq,
 static int mmc_blk_err_check(struct mmc_card *card,
 			     struct mmc_async_req *areq)
 {
-	enum mmc_blk_status ret = MMC_BLK_SUCCESS;
 	struct mmc_queue_req *mq_mrq = container_of(areq, struct mmc_queue_req,
 						    mmc_active);
 	struct mmc_blk_request *brq = &mq_mrq->brq;
 	struct request *req = mq_mrq->req;
+	int ecc_err = 0;
 
 	/*
 	 * sbc.error indicates a problem with the set block count
@@ -841,8 +899,9 @@ static int mmc_blk_err_check(struct mmc_card *card,
 	 * stop.error indicates a problem with the stop command.  Data
 	 * may have been transferred, or may still be transferring.
 	 */
-	if (brq->sbc.error || brq->cmd.error || brq->stop.error) {
-		switch (mmc_blk_cmd_recovery(card, req, brq)) {
+	if (brq->sbc.error || brq->cmd.error || brq->stop.error ||
+	    brq->data.error) {
+		switch (mmc_blk_cmd_recovery(card, req, brq, &ecc_err)) {
 		case ERR_RETRY:
 			return MMC_BLK_RETRY;
 		case ERR_ABORT:
@@ -894,23 +953,21 @@ static int mmc_blk_err_check(struct mmc_card *card,
 		       brq->cmd.resp[0], brq->stop.resp[0]);
 
 		if (rq_data_dir(req) == READ) {
-			if (brq->data.blocks > 1) {
-				/* Redo read one sector at a time */
-				pr_warning("%s: retrying using single block read\n",
-					   req->rq_disk->disk_name);
-				return MMC_BLK_RETRY_SINGLE;
-			}
+			if (ecc_err)
+				return MMC_BLK_ECC_ERR;
 			return MMC_BLK_DATA_ERR;
 		} else {
 			return MMC_BLK_CMD_ERR;
 		}
 	}
 
-	if (ret == MMC_BLK_SUCCESS &&
-	    blk_rq_bytes(req) != brq->data.bytes_xfered)
-		ret = MMC_BLK_PARTIAL;
+	if (!brq->data.bytes_xfered)
+		return MMC_BLK_RETRY;
 
-	return ret;
+	if (blk_rq_bytes(req) != brq->data.bytes_xfered)
+		return MMC_BLK_PARTIAL;
+
+	return MMC_BLK_SUCCESS;
 }
 
 static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq,
@@ -1046,12 +1103,41 @@ static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq,
 	mmc_queue_bounce_pre(mqrq);
 }
 
+static int mmc_blk_cmd_err(struct mmc_blk_data *md, struct mmc_card *card,
+			   struct mmc_blk_request *brq, struct request *req,
+			   int ret)
+{
+	/*
+	 * If this is an SD card and we're writing, we can first
+	 * mark the known good sectors as ok.
+	 *
+	 * If the card is not SD, we can still ok written sectors
+	 * as reported by the controller (which might be less than
+	 * the real number of written sectors, but never more).
+	 */
+	if (mmc_card_sd(card)) {
+		u32 blocks;
+
+		blocks = mmc_sd_num_wr_blocks(card);
+		if (blocks != (u32)-1) {
+			spin_lock_irq(&md->lock);
+			ret = __blk_end_request(req, 0, blocks << 9);
+			spin_unlock_irq(&md->lock);
+		}
+	} else {
+		spin_lock_irq(&md->lock);
+		ret = __blk_end_request(req, 0, brq->data.bytes_xfered);
+		spin_unlock_irq(&md->lock);
+	}
+	return ret;
+}
+
 static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
 {
 	struct mmc_blk_data *md = mq->data;
 	struct mmc_card *card = md->queue.card;
 	struct mmc_blk_request *brq = &mq->mqrq_cur->brq;
-	int ret = 1, disable_multi = 0, retry = 0;
+	int ret = 1, disable_multi = 0, retry = 0, type;
 	enum mmc_blk_status status;
 	struct mmc_queue_req *mq_rq;
 	struct request *req;
@@ -1073,6 +1159,7 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
 		mq_rq = container_of(areq, struct mmc_queue_req, mmc_active);
 		brq = &mq_rq->brq;
 		req = mq_rq->req;
+		type = rq_data_dir(req) == READ ? MMC_BLK_READ : MMC_BLK_WRITE;
 		mmc_queue_bounce_post(mq_rq);
 
 		switch (status) {
@@ -1081,17 +1168,17 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
 			/*
 			 * A block was successfully transferred.
 			 */
+			mmc_blk_reset_success(md, type);
 			spin_lock_irq(&md->lock);
 			ret = __blk_end_request(req, 0,
 						brq->data.bytes_xfered);
 			spin_unlock_irq(&md->lock);
+			/*
+			 * If the blk_end_request function returns non-zero even
+			 * though all data has been transferred and no errors
+			 * were returned by the host controller, it's a bug.
+			 */
 			if (status == MMC_BLK_SUCCESS && ret) {
-				/*
-				 * The blk_end_request has returned non zero
-				 * even though all data is transfered and no
-				 * erros returned by host.
-				 * If this happen it's a bug.
-				 */
 				printk(KERN_ERR "%s BUG rq_tot %d d_xfer %d\n",
 				       __func__, blk_rq_bytes(req),
 				       brq->data.bytes_xfered);
@@ -1100,16 +1187,36 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
 			}
 			break;
 		case MMC_BLK_CMD_ERR:
-			goto cmd_err;
-		case MMC_BLK_RETRY_SINGLE:
-			disable_multi = 1;
-			break;
+			ret = mmc_blk_cmd_err(md, card, brq, req, ret);
+			if (!mmc_blk_reset(md, card->host, type))
+				break;
+			goto cmd_abort;
 		case MMC_BLK_RETRY:
 			if (retry++ < 5)
 				break;
+			/* Fall through */
 		case MMC_BLK_ABORT:
+			if (!mmc_blk_reset(md, card->host, type))
+				break;
 			goto cmd_abort;
-		case MMC_BLK_DATA_ERR:
+		case MMC_BLK_DATA_ERR: {
+			int err;
+
+			err = mmc_blk_reset(md, card->host, type);
+			if (!err)
+				break;
+			if (err == -ENODEV)
+				goto cmd_abort;
+			/* Fall through */
+		}
+		case MMC_BLK_ECC_ERR:
+			if (brq->data.blocks > 1) {
+				/* Redo read one sector at a time */
+				pr_warning("%s: retrying using single block read\n",
+					   req->rq_disk->disk_name);
+				disable_multi = 1;
+				break;
+			}
 			/*
 			 * After an error, we redo I/O one sector at a
 			 * time, so we only reach here after trying to
@@ -1126,7 +1233,7 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
 
 		if (ret) {
 			/*
-			 * In case of a none complete request
+			 * In case of a incomplete request
 			 * prepare it again and resend.
 			 */
 			mmc_blk_rw_rq_prep(mq_rq, card, disable_multi, mq);
@@ -1136,30 +1243,6 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
 
 	return 1;
 
- cmd_err:
- 	/*
- 	 * If this is an SD card and we're writing, we can first
- 	 * mark the known good sectors as ok.
- 	 *
-	 * If the card is not SD, we can still ok written sectors
-	 * as reported by the controller (which might be less than
-	 * the real number of written sectors, but never more).
-	 */
-	if (mmc_card_sd(card)) {
-		u32 blocks;
-
-		blocks = mmc_sd_num_wr_blocks(card);
-		if (blocks != (u32)-1) {
-			spin_lock_irq(&md->lock);
-			ret = __blk_end_request(req, 0, blocks << 9);
-			spin_unlock_irq(&md->lock);
-		}
-	} else {
-		spin_lock_irq(&md->lock);
-		ret = __blk_end_request(req, 0, brq->data.bytes_xfered);
-		spin_unlock_irq(&md->lock);
-	}
-
  cmd_abort:
 	spin_lock_irq(&md->lock);
 	while (ret)
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 3bdb981..2f6897c 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1521,7 +1521,7 @@ static int mmc_do_erase(struct mmc_card *card, unsigned int from,
 	if (err) {
 		printk(KERN_ERR "mmc_erase: group start error %d, "
 		       "status %#x\n", err, cmd.resp[0]);
-		err = -EINVAL;
+		err = -EIO;
 		goto out;
 	}
 
@@ -1536,7 +1536,7 @@ static int mmc_do_erase(struct mmc_card *card, unsigned int from,
 	if (err) {
 		printk(KERN_ERR "mmc_erase: group end error %d, status %#x\n",
 		       err, cmd.resp[0]);
-		err = -EINVAL;
+		err = -EIO;
 		goto out;
 	}
 
-- 
1.7.6

Re: [PATCH 0/5] mmc: add eMMC hardware reset support

[Chris Ball]

Hi Adrian,

On Mon, Aug 29 2011, Adrian Hunter wrote:
> Here are some patches to add eMMC hardware reset support.
>
> Adrian Hunter (5):
>       mmc: add eMMC hardware reset support
>       mmc: sdhci: add eMMC hardware reset support
>       mmc: sdhci-pci: add eMMC hardware reset support
>       mmc: mmc-test: add eMMC hardware reset test
>       mmc: block: add eMMC hardware reset support

Thanks, all pushed to mmc-next for 3.2.

- Chris.
-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child

Re: [PATCH 1/5] mmc: add eMMC hardware reset support

[Chris Ball]

Hi Adrian,

On Mon, Aug 29 2011, Adrian Hunter wrote:
> +	host->ios.ddr = MMC_SDR_MODE;

This doesn't build, because the ddr field no longer exists in the ios
struct, as of 4c4cb171 and 7fd781e8f -- we're using ios.timing instead
now.  I'll modify your patch to remove this line completely, let me know
if you disagree.

Thanks,

- Chris.
-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child