> -----Original Message-----
> From: Subhash Jadavani [mailto:subha...@codeaurora.org]
> Sent: Wednesday, March 23, 2011 12:04 PM
> To: Nath, Arindam; c...@laptop.org
> Cc: zhangfei....@gmail.com; prak...@marvell.com; linux-
> m...@vger.kernel.org; Su, Henry; Lu, Aaron; anath....@gmail.com
> Subject: RE: [PATCH v2 09/12] mmc: sd: add support for tuning during
> uhs initialization
>
>
>
> > -----Original Message-----
> > From: linux-mmc-ow...@vger.kernel.org [mailto:linux-mmc-
> > ow...@vger.kernel.org] On Behalf Of Nath, Arindam
> > Sent: Wednesday, March 23, 2011 11:53 AM
> > To: Subhash Jadavani; c...@laptop.org
> > Cc: zhangfei....@gmail.com; prak...@marvell.com; linux-
> > m...@vger.kernel.org; Su, Henry; Lu, Aaron; anath....@gmail.com
> > Subject: RE: [PATCH v2 09/12] mmc: sd: add support for tuning during
> > uhs initialization
> >
> > Hi Subhash,
> >
> >
> > > -----Original Message-----
> > > From: Subhash Jadavani [mailto:subha...@codeaurora.org]
> > > Sent: Wednesday, March 23, 2011 11:50 AM
> > > To: Nath, Arindam; c...@laptop.org
> > > Cc: zhangfei....@gmail.com; prak...@marvell.com; linux-
> > > m...@vger.kernel.org; Su, Henry; Lu, Aaron; anath....@gmail.com
> > > Subject: RE: [PATCH v2 09/12] mmc: sd: add support for tuning
> during
> > > uhs initialization
> > >
> > >
> > >
> > > > -----Original Message-----
> > > > From: Nath, Arindam [mailto:arindam.n...@amd.com]
> > > > Sent: Wednesday, March 23, 2011 11:45 AM
> > > > To: Subhash Jadavani; c...@laptop.org
> > > > Cc: zhangfei....@gmail.com; prak...@marvell.com; linux-
> > > > m...@vger.kernel.org; Su, Henry; Lu, Aaron; anath....@gmail.com
> > > > Subject: RE: [PATCH v2 09/12] mmc: sd: add support for tuning
> > during
> > > > uhs initialization
> > > >
> > > > Hi Subhash,
> > > >
> > > >
> > > > > -----Original Message-----
> > > > > From: Subhash Jadavani [mailto:subha...@codeaurora.org]
> > > > > Sent: Wednesday, March 23, 2011 11:38 AM
> > > > > To: Nath, Arindam; c...@laptop.org
> > > > > Cc: zhangfei....@gmail.com; prak...@marvell.com; linux-
> > > > > m...@vger.kernel.org; Su, Henry; Lu, Aaron; anath....@gmail.com
> > > > > Subject: RE: [PATCH v2 09/12] mmc: sd: add support for tuning
> > > during
> > > > > uhs initialization
> > > > >
> > > > >
> > > > >
> > > > > > -----Original Message-----
> > > > > > From: linux-mmc-ow...@vger.kernel.org [mailto:linux-mmc-
> > > > > > ow...@vger.kernel.org] On Behalf Of Nath, Arindam
> > > > > > Sent: Monday, March 21, 2011 4:37 PM
> > > > > > To: Subhash Jadavani; c...@laptop.org
> > > > > > Cc: zhangfei....@gmail.com; prak...@marvell.com; linux-
> > > > > > m...@vger.kernel.org; Su, Henry; Lu, Aaron;
> anath....@gmail.com
> > > > > > Subject: RE: [PATCH v2 09/12] mmc: sd: add support for tuning
> > > > during
> > > > > > uhs initialization
> > > > > >
> > > > > > Hi Subhash,
> > > > > >
> > > > > >
> > > > > > > -----Original Message-----
> > > > > > > From: Subhash Jadavani [mailto:subha...@codeaurora.org]
> > > > > > > Sent: Monday, March 21, 2011 4:29 PM
> > > > > > > To: Nath, Arindam; c...@laptop.org
> > > > > > > Cc: zhangfei....@gmail.com; prak...@marvell.com; linux-
> > > > > > > m...@vger.kernel.org; Su, Henry; Lu, Aaron;
> > anath....@gmail.com
> > > > > > > Subject: RE: [PATCH v2 09/12] mmc: sd: add support for
> tuning
> > > > > during
> > > > > > > uhs initialization
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > > > -----Original Message-----
> > > > > > > > From: Arindam Nath [mailto:anath....@gmail.com] On Behalf
> > Of
> > > > > > Arindam
> > > > > > > > Nath
> > > > > > > > Sent: Friday, March 04, 2011 5:03 PM
> > > > > > > > To: c...@laptop.org
> > > > > > > > Cc: zhangfei....@gmail.com; prak...@marvell.com;
> > > > > > > > subha...@codeaurora.org; linux-mmc@vger.kernel.org;
> > > > > > henry...@amd.com;
> > > > > > > > aaron...@amd.com; anath....@gmail.com; Arindam Nath
> > > > > > > > Subject: [PATCH v2 09/12] mmc: sd: add support for tuning
> > > > during
> > > > > > uhs
> > > > > > > > initialization
> > > > > > > >
> > > > > > > > Host Controller needs tuning during initialization to
> > operate
> > > > > SDR50
> > > > > > > > and SDR104 UHS-I cards. Whether SDR50 mode actually needs
> > > > tuning
> > > > > is
> > > > > > > > indicated by bit 45 of the Host Controller Capabilities
> > > > register.
> > > > > > > > A new command CMD19 has been defined in the Physical
> Layer
> > > spec
> > > > > > > > v3.01 to request the card to send tuning pattern.
> > > > > > > >
> > > > > > > > We enable Buffer Read Ready interrupt at the very
> begining
> > of
> > > > > > tuning
> > > > > > > > procedure, because that is the only interrupt generated
> by
> > > the
> > > > > Host
> > > > > > > > Controller during tuning. The tuning block is sent by the
> > > card
> > > > to
> > > > > > the
> > > > > > > > Host Controller using DAT lines, so we set Data Present
> > > Select
> > > > > (bit
> > > > > > > 5)
> > > > > > > > in the Command register. The Host Controller is
> responsible
> > > for
> > > > > > doing
> > > > > > > > the verfication of tuning block sent by the card at the
> > > > hardware
> > > > > > > level.
> > > > > > > > After sending CMD19, we wait for Buffer Read Ready
> > interrupt.
> > > > In
> > > > > > case
> > > > > > > > we don't receive an interrupt after the specified timeout
> > > > value,
> > > > > we
> > > > > > > > fall back on fixed sampling clock by setting Execute
> Tuning
> > > > (bit
> > > > > 6)
> > > > > > > > and Sampling Clock Seletc (bit 7) of Host Control2
> register
> > > to
> > > > 0.
> > > > > > > > Before exiting the tuning procedure, we disable Buffer
> Read
> > > > Ready
> > > > > > > > interrupt.
> > > > > > > >
> > > > > > > > Signed-off-by: Arindam Nath <arindam.n...@amd.com>
> > > > > > > > ---
> > > > > > > > drivers/mmc/core/sd.c | 4 +
> > > > > > > > drivers/mmc/host/sdhci.c | 137
> > > > > > > > ++++++++++++++++++++++++++++++++++++++++++++-
> > > > > > > > drivers/mmc/host/sdhci.h | 3 +
> > > > > > > > include/linux/mmc/host.h | 1 +
> > > > > > > > include/linux/mmc/mmc.h | 1 +
> > > > > > > > include/linux/mmc/sdhci.h | 4 +
> > > > > > > > 6 files changed, 149 insertions(+), 1 deletions(-)
> > > > > > > >
> > > > > > > > diff --git a/drivers/mmc/core/sd.c
> b/drivers/mmc/core/sd.c
> > > > > > > > index be01397..1e2d157 100644
> > > > > > > > --- a/drivers/mmc/core/sd.c
> > > > > > > > +++ b/drivers/mmc/core/sd.c
> > > > > > > > @@ -637,6 +637,10 @@ static int
> mmc_sd_init_uhs_card(struct
> > > > > > mmc_card
> > > > > > > > *card)
> > > > > > > > /* Set current limit for the card */
> > > > > > > > err = sd_set_current_limit(card, status);
> > > > > > > >
> > > > > > > > + /* SPI mode doesn't define CMD19 */
> > > > > > > > + if (!mmc_host_is_spi(card->host) && card->host-
> > >ops-
> > > > > > > > >execute_tuning)
> > > > > > > > + card->host->ops->execute_tuning(card-
> > >host);
> > > > > > > > +
> > > > > > > > out:
> > > > > > > > kfree(status);
> > > > > > > >
> > > > > > > > diff --git a/drivers/mmc/host/sdhci.c
> > > > b/drivers/mmc/host/sdhci.c
> > > > > > > > index 245cc39..8f4f102 100644
> > > > > > > > --- a/drivers/mmc/host/sdhci.c
> > > > > > > > +++ b/drivers/mmc/host/sdhci.c
> > > > > > > > @@ -39,6 +39,8 @@
> > > > > > > > #define SDHCI_USE_LEDS_CLASS
> > > > > > > > #endif
> > > > > > > >
> > > > > > > > +#define MAX_TUNING_LOOP 40
> > > > > > > > +
> > > > > > > > static unsigned int debug_quirks = 0;
> > > > > > > >
> > > > > > > > static void sdhci_prepare_data(struct sdhci_host *,
> struct
> > > > > > mmc_data
> > > > > > > > *);
> > > > > > > > @@ -985,7 +987,9 @@ static void sdhci_send_command(struct
> > > > > > sdhci_host
> > > > > > > > *host, struct mmc_command *cmd)
> > > > > > > > flags |= SDHCI_CMD_CRC;
> > > > > > > > if (cmd->flags & MMC_RSP_OPCODE)
> > > > > > > > flags |= SDHCI_CMD_INDEX;
> > > > > > > > - if (cmd->data)
> > > > > > > > +
> > > > > > > > + /* CMD19 is special in that the Data Present
> Select
> > > > should
> > > > > be set
> > > > > > > > */
> > > > > > > > + if (cmd->data || (cmd->opcode ==
> > > > MMC_SEND_TUNING_BLOCK))
> > > > > > > > flags |= SDHCI_CMD_DATA;
> > > > > > > >
> > > > > > > > sdhci_writew(host, SDHCI_MAKE_CMD(cmd->opcode,
> > > flags),
> > > > > > > > SDHCI_COMMAND);
> > > > > > > > @@ -1485,6 +1489,119 @@ static int
> > > > > sdhci_get_max_current_180(struct
> > > > > > > > mmc_host *mmc)
> > > > > > > > return max_current_180;
> > > > > > > > }
> > > > > > > >
> > > > > > > > +static void sdhci_execute_tuning(struct mmc_host *mmc)
> > > > > > > > +{
> > > > > > > > + struct sdhci_host *host;
> > > > > > > > + u16 ctrl;
> > > > > > > > + int tuning_loop_counter = MAX_TUNING_LOOP;
> > > > > > > > + unsigned long flags;
> > > > > > > > + unsigned long timeout;
> > > > > > > > +
> > > > > > > > + host = mmc_priv(mmc);
> > > > > > > > +
> > > > > > > > + spin_lock_irqsave(&host->lock, flags);
> > > > > > > > +
> > > > > > > > + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
> > > > > > > > +
> > > > > > > > + /*
> > > > > > > > + * Host Controller needs tuning only in case of
> > > SDR104
> > > > mode
> > > > > > > > + * and for SDR50 mode when Use Tuning for SDR50
> is
> > > set
> > > > in
> > > > > > > > + * Capabilities register.
> > > > > > > > + */
> > > > > > > > + if ((ctrl & SDHCI_CTRL_UHS_SDR104) ||
> > > > > > > > + ((ctrl & SDHCI_CTRL_UHS_SDR50) &&
> > > > > > > > + (host->flags & SDHCI_SDR50_NEEDS_TUNING)))
> > > > > > > > + ctrl |= SDHCI_CTRL_EXEC_TUNING;
> > > > > > > > + else {
> > > > > > > > + spin_unlock_irqrestore(&host->lock,
> flags);
> > > > > > > > + return;
> > > > > > > > + }
> > > > > > > > +
> > > > > > > > + sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
> > > > > > > > +
> > > > > > > > + /*
> > > > > > > > + * As per the Host Controller spec v3.00, tuning
> > > > command
> > > > > > > > + * generates Buffer Read Ready interrupt, so
> enable
> > > > that.
> > > > > > > > + */
> > > > > > > > + sdhci_unmask_irqs(host, SDHCI_INT_DATA_AVAIL);
> > > > > > > > +
> > > > > > > > + /*
> > > > > > > > + * Issue CMD19 repeatedly till Execute Tuning is
> > set
> > > to
> > > > 0
> > > > > or the
> > > > > > > > number
> > > > > > > > + * of loops reaches 40 times or a timeout of
> 150ms
> > > > occurs.
> > > > > > > > + */
> > > > > > > > + timeout = 150;
> > > > > > > > + do {
> > > > > > > > + struct mmc_command cmd;
> > > > > > > > + struct mmc_request mrq;
> > > > > > > > +
> > > > > > > > + if (!tuning_loop_counter && !timeout)
> > > > > > > > + break;
> > > > > > > > +
> > > > > > > > + memset(&cmd, 0, sizeof(struct
> > mmc_command));
> > > > > > > > + cmd.opcode = MMC_SEND_TUNING_BLOCK;
> > > > > > > > + cmd.arg = 0;
> > > > > > > > + cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
> > > > > > > > +
> > > > > > > > + memset(&cmd.resp, 0, sizeof(cmd.resp));
> > > > > > > > + cmd.retries = 0;
> > > > > > > > +
> > > > > > > > + cmd.data = NULL;
> > > > > > > > + cmd.error = 0;
> > > > > > > > +
> > > > > > > > + memset(&mrq, 0, sizeof(struct
> > mmc_request));
> > > > > > > > + mrq.cmd = &cmd;
> > > > > > > > + host->mrq = &mrq;
> > > > > > > > + sdhci_send_command(host, &cmd);
> > > > > > > > +
> > > > > > > > + host->cmd = NULL;
> > > > > > > > + host->mrq = NULL;
> > > > > > > > +
> > > > > > > > + spin_unlock_irqrestore(&host->lock,
> flags);
> > > > > > > > +
> > > > > > > > + /* Wait for Buffer Read Ready interrupt
> */
> > > > > > > > + wait_event_interruptible_timeout(host-
> > > > >buf_ready_int,
> > > > > > > > + (host-
> >tuning_done
> > ==
> > > > 1),
> > > > > > > > +
> > > msecs_to_jiffies(50));
> > > > > > > > + spin_lock_irqsave(&host->lock, flags);
> > > > > > > > +
> > > > > > > > + if (!host->tuning_done) {
> > > > > > > > + printk(KERN_INFO DRIVER_NAME ":
> > > Tuning
> > > > > procedure"
> > > > > > > > + " failed, falling back to
> > > fixed
> > > > sampling"
> > > > > > > > + " clock\n");
> > > > > > > > + ctrl &= ~SDHCI_CTRL_TUNED_CLK;
> > > > > > > > + ctrl &= ~SDHCI_CTRL_EXEC_TUNING;
> > > > > > > > + sdhci_writew(host, ctrl,
> > > > SDHCI_HOST_CONTROL2);
> > > > > > > > +
> > > > > > > > + goto out;
> > > > > > > > + }
> > > > > > > > +
> > > > > > > > + host->tuning_done = 0;
> > > > > > > > +
> > > > > > > > + ctrl = sdhci_readw(host,
> > > SDHCI_HOST_CONTROL2);
> > > > > > > > + tuning_loop_counter--;
> > > > > > > > + timeout--;
> > > > > > > > + mdelay(1);
> > > > > > > > + } while (ctrl & SDHCI_CTRL_EXEC_TUNING);
> > > > > > > > +
> > > > > > > > + /*
> > > > > > > > + * The Host Driver has exhausted the maximum
> number
> > > of
> > > > > loops
> > > > > > > > allowed,
> > > > > > > > + * so use fixed sampling frequency.
> > > > > > > > + */
> > > > > > > > + if (!tuning_loop_counter || !timeout) {
> > > > > > > > + ctrl &= ~SDHCI_CTRL_TUNED_CLK;
> > > > > > > > + sdhci_writew(host, ctrl,
> > > SDHCI_HOST_CONTROL2);
> > > > > > > > + } else {
> > > > > > > > + if (!(ctrl & SDHCI_CTRL_TUNED_CLK))
> > > > > > > > + printk(KERN_INFO DRIVER_NAME ":
> > > Tuning
> > > > > procedure"
> > > > > > > > + " failed, falling back to
> > > fixed
> > > > sampling"
> > > > > > > > + " clock\n");
> > > > > > > > + }
> > > > > > > > +
> > > > > > > > +out:
> > > > > > > > + sdhci_mask_irqs(host, SDHCI_INT_DATA_AVAIL);
> > > > > > > > + spin_unlock_irqrestore(&host->lock, flags);
> > > > > > > > +}
> > > > > > > > +
> > > > > > > > static const struct mmc_host_ops sdhci_ops = {
> > > > > > > > .request = sdhci_request,
> > > > > > > > .set_ios = sdhci_set_ios,
> > > > > > > > @@ -1492,6 +1609,7 @@ static const struct mmc_host_ops
> > > > sdhci_ops
> > > > > =
> > > > > > {
> > > > > > > > .enable_sdio_irq = sdhci_enable_sdio_irq,
> > > > > > > > .start_signal_voltage_switch =
> > > > > > > > sdhci_start_signal_voltage_switch,
> > > > > > > > .get_max_current_180 =
> > > > sdhci_get_max_current_180,
> > > > > > > > + .execute_tuning =
> > > sdhci_execute_tuning,
> > > > > > > > };
> > > > > > > >
> > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> /**********************************************************************
> > > > > > > > *******\
> > > > > > > > @@ -1703,6 +1821,16 @@ static void sdhci_data_irq(struct
> > > > > sdhci_host
> > > > > > > > *host, u32 intmask)
> > > > > > > > {
> > > > > > > > BUG_ON(intmask == 0);
> > > > > > > >
> > > > > > > > + /* CMD19 generates _only_ Buffer Read Ready
> > interrupt
> > > > */
> > > > > > > > + if (intmask & SDHCI_INT_DATA_AVAIL) {
> > > > > > > > + if (SDHCI_GET_CMD(sdhci_readw(host,
> > > > SDHCI_COMMAND))
> > > > > > > > + == MMC_SEND_TUNING_BLOCK)
> {
> > > > > > > > + host->tuning_done = 1;
> > > > > > > > + wake_up(&host->buf_ready_int);
> > > > > > > > + return;
> > > > > > > > + }
> > > > > > > > + }
> > > > > > > > +
> > > > > > > > if (!host->data) {
> > > > > > > > /*
> > > > > > > > * The "data complete" interrupt is also
> > used
> > > > to
> > > > > > > > @@ -2126,6 +2254,10 @@ int sdhci_add_host(struct
> sdhci_host
> > > > > *host)
> > > > > > > > if (caps[1] & SDHCI_SUPPORT_DDR50)
> > > > > > > > mmc->caps |= MMC_CAP_UHS_DDR50;
> > > > > > > >
> > > > > > > > + /* Does the host needs tuning for SDR50? */
> > > > > > > > + if (caps[1] & SDHCI_USE_SDR50_TUNING)
> > > > > > > > + host->flags |= SDHCI_SDR50_NEEDS_TUNING;
> > > > > > > > +
> > > > > > > > /* Driver Type(s) (A, C, D) supported by the host
> > */
> > > > > > > > if (caps[1] & SDHCI_DRIVER_TYPE_A)
> > > > > > > > mmc->caps |= MMC_CAP_DRIVER_TYPE_A;
> > > > > > > > @@ -2269,6 +2401,9 @@ int sdhci_add_host(struct
> sdhci_host
> > > > *host)
> > > > > > > >
> > > > > > > > setup_timer(&host->timer, sdhci_timeout_timer,
> > > > (unsigned
> > > > > > > > long)host);
> > > > > > > >
> > > > > > > > + if (host->version >= SDHCI_SPEC_300)
> > > > > > > > + init_waitqueue_head(&host-
> >buf_ready_int);
> > > > > > > > +
> > > > > > > > ret = request_irq(host->irq, sdhci_irq,
> > IRQF_SHARED,
> > > > > > > > mmc_hostname(mmc), host);
> > > > > > > > if (ret)
> > > > > > > > diff --git a/drivers/mmc/host/sdhci.h
> > > > b/drivers/mmc/host/sdhci.h
> > > > > > > > index 5bf244d..4746879 100644
> > > > > > > > --- a/drivers/mmc/host/sdhci.h
> > > > > > > > +++ b/drivers/mmc/host/sdhci.h
> > > > > > > > @@ -160,6 +160,8 @@
> > > > > > > > #define SDHCI_CTRL_DRV_TYPE_A 0x0010
> > > > > > > > #define SDHCI_CTRL_DRV_TYPE_C 0x0020
> > > > > > > > #define SDHCI_CTRL_DRV_TYPE_D 0x0030
> > > > > > > > +#define SDHCI_CTRL_EXEC_TUNING 0x0040
> > > > > > > > +#define SDHCI_CTRL_TUNED_CLK 0x0080
> > > > > > > > #define SDHCI_CTRL_PRESET_VAL_ENABLE 0x8000
> > > > > > > >
> > > > > > > > #define SDHCI_CAPABILITIES 0x40
> > > > > > > > @@ -187,6 +189,7 @@
> > > > > > > > #define SDHCI_DRIVER_TYPE_A 0x00000010
> > > > > > > > #define SDHCI_DRIVER_TYPE_C 0x00000020
> > > > > > > > #define SDHCI_DRIVER_TYPE_D 0x00000040
> > > > > > > > +#define SDHCI_USE_SDR50_TUNING 0x00002000
> > > > > > > >
> > > > > > > > #define SDHCI_CAPABILITIES_1 0x44
> > > > > > > >
> > > > > > > > diff --git a/include/linux/mmc/host.h
> > > > b/include/linux/mmc/host.h
> > > > > > > > index e84cd05..651e40b 100644
> > > > > > > > --- a/include/linux/mmc/host.h
> > > > > > > > +++ b/include/linux/mmc/host.h
> > > > > > > > @@ -129,6 +129,7 @@ struct mmc_host_ops {
> > > > > > > >
> > > > > > > > int (*start_signal_voltage_switch)(struct
> > > mmc_host
> > > > > *host);
> > > > > > > > int (*get_max_current_180)(struct mmc_host
> > *mmc);
> > > > > > > > + void (*execute_tuning)(struct mmc_host *host);
> > > > > > >
> > > > > > >
> > > > > > > Why execute_tuning ops return type is void? Will there not
> be
> > > any
> > > > > > error
> > > > > > > scenarios? What if host fails to find any tuning point?
> > > Shouldn't
> > > > > it
> > > > > > > return
> > > > > > > error to the core layer and then core layer should not
> begin
> > > with
> > > > > the
> > > > > > > any
> > > > > > > read/write operations?
> > > > > >
> > > > > > In case the tuning procedure fails, Host Controller falls
> back
> > on
> > > > > using
> > > > > > Fixed Sampling clock, so data transfer can still continue.
> > > > > >
> > > > >
> > > > > I think that's not a correct assumption. Let's say tuning fails
> > and
> > > > > host
> > > > > controller falls back to fixed sampling clock and card still
> > > operates
> > > > > in
> > > > > SDR104 with CLK=208MHz. This means that all further read/write
> > > > > transactions
> > > > > will mainly result in CRC Fail errors and none of the
> > transactions
> > > > may
> > > > > be
> > > > > successful. So we can't just leave the host controller in state
> > > where
> > > > > it
> > > > > cannot perform high speed transfers (because it's tuning had
> > > failed)
> > > > > and
> > > > > then start issuing commands with high speed transfer conditions
> > > > > (CLK=208MHz). Better way is for host to inform core layer that
> > > tuning
> > > > > has
> > > > > failed and then there should not be any further transactions
> with
> > > the
> > > > > card
> > > > > or fallback to low speed modes (SDR12, SDR25 or SDR50) or power
> > > cycle
> > > > > the
> > > > > card.
> > > >
> > > > The host controller spec v3.00 clearly says that the occurrence
> of
> > an
> > > > error during tuning procedure is indicated by Sampling Select,
> > which
> > > > will be set to 0 in case tuning fails. But that won't stop the
> > > > controller to retry re-tuning procedure based on the re-tuning
> > mode.
> > > So
> > > > I don't see any reason for transaction to be stopped in case
> tuning
> > > > fails.
> > >
> > > This capability is not there with host controller on our chipsets.
> So
> > > then
> > > what to do? I think referring Host controller spec v3.00 should not
> > be
> > > proper here. As this spec is not a must condition for all host
> > > controller
> > > implementations.
> >
> > In that case, I would really appreciate if you could implement the
> > procedure which will work for your controller, and then we can merge
> > the code with mine.
>
> Ok that's fine. but that doesn't mean "execute_tuning" ops should not
> have
> any return type in your implementation. We should be able to return the
> error from this ops. From your driver you can always return the success
> from
> "execute_tuning" ops which should solve your purpose. In case
> "execute_tuning" returns error then "mmc_sd_init_uhs_card" would return
> error which would result in removing the card.
>
> So this way it should satisfy all the different implementations of
> "execute_tuning" ops by different host controller drivers.
>
> Please let me know if this is fine with you or not?
If you want me to return error the very first time tuning fails, and the card
being removed, I am fine with that. But I am not sure if all the host
controller would be happy with the implementation. Since some controller like
ours would still want re-tuning to be tried the next time round. Anyways, I
will implement your suggestion.
Thanks,
Arindam
>
>
> >
> > Thanks,
> > Arindam
> >
> > >
> > >
> > > >
> > > > Thanks,
> > > > Arindam
> > > >
> > > > >
> > > > >
> > > > > > Thanks,
> > > > > > Arindam
> > > > > >
> > > > > > >
> > > > > > >
> > > > > > > > };
> > > > > > > >
> > > > > > > > struct mmc_card;
> > > > > > > > diff --git a/include/linux/mmc/mmc.h
> > > b/include/linux/mmc/mmc.h
> > > > > > > > index 612301f..9194f9e 100644
> > > > > > > > --- a/include/linux/mmc/mmc.h
> > > > > > > > +++ b/include/linux/mmc/mmc.h
> > > > > > > > @@ -50,6 +50,7 @@
> > > > > > > > #define MMC_SET_BLOCKLEN 16 /* ac [31:0]
> block
> > > len
> > > > > > R1
> > > > > > > > */
> > > > > > > > #define MMC_READ_SINGLE_BLOCK 17 /* adtc [31:0]
> data
> > > addr
> > > > > > R1
> > > > > > > > */
> > > > > > > > #define MMC_READ_MULTIPLE_BLOCK 18 /* adtc [31:0]
> data
> > > addr
> > > > > > R1
> > > > > > > > */
> > > > > > > > +#define MMC_SEND_TUNING_BLOCK 19 /* adtc
> > > > > > R1
> > > > > > > > */
> > > > > > > >
> > > > > > > > /* class 3 */
> > > > > > > > #define MMC_WRITE_DAT_UNTIL_STOP 20 /* adtc [31:0]
> data
> > > addr
> > > > > > R1
> > > > > > > > */
> > > > > > > > diff --git a/include/linux/mmc/sdhci.h
> > > > > b/include/linux/mmc/sdhci.h
> > > > > > > > index 282d158..5203b97 100644
> > > > > > > > --- a/include/linux/mmc/sdhci.h
> > > > > > > > +++ b/include/linux/mmc/sdhci.h
> > > > > > > > @@ -109,6 +109,7 @@ struct sdhci_host {
> > > > > > > > #define SDHCI_USE_ADMA (1<<1) /* Host is ADMA
> > > capable
> > > > > > > */
> > > > > > > > #define SDHCI_REQ_USE_DMA (1<<2) /* Use DMA for
> this
> > > > > > req. */
> > > > > > > > #define SDHCI_DEVICE_DEAD (1<<3) /* Device
> > > unresponsive
> > > > > > */
> > > > > > > > +#define SDHCI_SDR50_NEEDS_TUNING (1<<4) /* SDR50
> > > needs
> > > > tuning
> > > > > > > */
> > > > > > > >
> > > > > > > > unsigned int version; /* SDHCI spec. version */
> > > > > > > >
> > > > > > > > @@ -147,6 +148,9 @@ struct sdhci_host {
> > > > > > > >
> > > > > > > > struct mmc_command *saved_abort_cmd; /*
> Abort
> > > > command
> > > > > saved
> > > > > > > > for data error recovery */
> > > > > > > >
> > > > > > > > + wait_queue_head_t buf_ready_int; /*
> > Waitqueue
> > > > for Buffer
> > > > > Read
> > > > > > > > Ready interrupt */
> > > > > > > > + unsigned int tuning_done; /*
> > Condition
> > > > flag
> > > > > set
> > > > > > > > when CMD19 succeeds */
> > > > > > > > +
> > > > > > > > unsigned long private[0] ____cacheline_aligned;
> > > > > > > > };
> > > > > > > > #endif /* __SDHCI_H */
> > > > > > > > --
> > > > > > > > 1.7.1
> > > > > > >
> > > > > > >
> > > > > >
> > > > > >
> > > > > > --
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> > > > mmc"
> > > > > in
> > > > > > the body of a message to majord...@vger.kernel.org
> > > > > > More majordomo info at http://vger.kernel.org/majordomo-
> > > info.html
> > > > >
> > > >
> > >
> > >
> >
> >
> > --
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