Hi Subhash, > -----Original Message----- > From: subhashj@xxxxxxxxxxxxxx [mailto:subhashj@xxxxxxxxxxxxxx] > Sent: Wednesday, March 09, 2011 5:52 PM > To: Nath, Arindam; cjb@xxxxxxxxxx > Cc: zhangfei.gao@xxxxxxxxx; prakity@xxxxxxxxxxx; linux- > mmc@xxxxxxxxxxxxxxx; Su, Henry; Lu, Aaron; anath.amd@xxxxxxxxx > Subject: RE: [PATCH v2 01/12] mmc: sdhci: add support for auto CMD23 > > > > > -----Original Message----- > > From: linux-mmc-owner@xxxxxxxxxxxxxxx [mailto:linux-mmc- > > owner@xxxxxxxxxxxxxxx] On Behalf Of Arindam Nath > > Sent: Friday, March 04, 2011 5:03 PM > > To: cjb@xxxxxxxxxx > > Cc: zhangfei.gao@xxxxxxxxx; prakity@xxxxxxxxxxx; > > subhashj@xxxxxxxxxxxxxx; linux-mmc@xxxxxxxxxxxxxxx; henry.su@xxxxxxx; > > aaron.lu@xxxxxxx; anath.amd@xxxxxxxxx; Arindam Nath > > Subject: [PATCH v2 01/12] mmc: sdhci: add support for auto CMD23 > > > > 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. > > > > Two bits are added to SCR register as per the Physical Layer Spec > > v3.01, > > which specify whether the card supports CMD20 and/or CMD23. We use > this > > as one of the conditions to decide whether to enable Auto CMD23 or > not. > > > > Signed-off-by: Arindam Nath <arindam.nath@xxxxxxx> > > --- > > drivers/mmc/core/sd.c | 6 ++++ > > drivers/mmc/host/sdhci.c | 69 > > +++++++++++++++++++++++++++++++++++++++++--- > > 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, 79 insertions(+), 6 deletions(-) > > > > diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c > > index d18c32b..b3f8a3c 100644 > > --- a/drivers/mmc/core/sd.c > > +++ b/drivers/mmc/core/sd.c > > @@ -188,6 +188,12 @@ 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); > > + } > Looks fine. > > > > > 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 9e15f41..8914a25 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" > > > > @@ -812,6 +813,30 @@ static void sdhci_prepare_data(struct sdhci_host > > *host, struct mmc_data *data) > > 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_supported(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; > > +} > Just a thought. Shouldn't the name should say *cmd23_required? Because > here > you are not just checking the card capability but also checking if > current > command requires CMD23 or not. Yes, *cmd23_required looks good to me. I will change the function name. > > > + > > static void sdhci_set_transfer_mode(struct sdhci_host *host, > > struct mmc_data *data) > > { > > @@ -825,10 +850,21 @@ 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_supported(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) > > @@ -1131,6 +1167,23 @@ 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_supported(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; > > @@ -1396,6 +1449,7 @@ static void sdhci_timeout_timer(unsigned long > > data) > > > > if (host->data) { > > host->data->error = -ETIMEDOUT; > > + host->data->stop = host->saved_abort_cmd; > > sdhci_finish_data(host); > > } else { > > if (host->cmd) > > @@ -1534,9 +1588,10 @@ static void sdhci_data_irq(struct sdhci_host > > *host, u32 intmask) > > host->data->error = -EIO; > > } > > > > - if (host->data->error) > > + if (host->data->error) { > > + 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); > > > > @@ -1792,6 +1847,10 @@ 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 6e0969e..223762c 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 8ce0827..22b0335 100644 > > --- a/include/linux/mmc/card.h > > +++ b/include/linux/mmc/card.h > > @@ -58,9 +58,13 @@ 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) > Looks good. I am just curious about: spec says that UHS104 card must > support > CMD23. so are you handling this anywhere? Means what if card is > detected as > UHS104 card and if it doesn't set this CMD23 bit? Just an error > condition. The description from Auto CMD23 Enable in the spec mentions card supporting CMD23 as a _required_ condition before using Auto CMD23. So I assume UHS104 cards should have this bit set for sure. Thanks, Arindam -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
