> -----Original Message-----
> From: [email protected] [mailto:linux-mmc-
> [email protected]] On Behalf Of Arindam Nath
> Sent: Friday, March 04, 2011 5:03 PM
> To: [email protected]
> Cc: [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; Arindam Nath
> Subject: [PATCH v2 04/12] mmc: sd: add support for driver type
> selection
>
> This patch adds support for setting driver strength during UHS-I
> initialization prcedure. Since UHS-I cards set S18A (bit 24) in
> response to ACMD41, we use this as a base for UHS-I initialization.
> We modify the parameter list of mmc_sd_get_cid() so that we can
> save the ROCR from ACMD41 to check whether bit 24 is set.
>
> We decide whether the Host Controller supports A, C, or D driver
> type depending on the Capabilities register. We then set the
> appropriate driver type for the card using CMD6 mode 1. As per
> Host Controller spec v3.00, we set driver type for the host only
> if Preset Value Enable in the Host Control2 register is not set.
> SDHCI_HOST_CONTROL has been renamed to SDHCI_HOST_CONTROL1 to
> conform to the spec.
>
> Signed-off-by: Arindam Nath <[email protected]>
> ---
> drivers/mmc/core/core.c | 9 +++
> drivers/mmc/core/core.h | 1 +
> drivers/mmc/core/sd.c | 140 +++++++++++++++++++++++++++++++++++++-
> --------
> drivers/mmc/core/sd.h | 3 +-
> drivers/mmc/core/sdio.c | 3 +-
> drivers/mmc/host/sdhci.c | 48 ++++++++++++----
> drivers/mmc/host/sdhci.h | 10 +++-
> include/linux/mmc/card.h | 4 +
> include/linux/mmc/host.h | 8 +++
> 9 files changed, 186 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> index 6625c05..daa535a 100644
> --- a/drivers/mmc/core/core.c
> +++ b/drivers/mmc/core/core.c
> @@ -947,6 +947,15 @@ void mmc_set_timing(struct mmc_host *host,
> unsigned int timing)
> }
>
> /*
> + * Select appropriate driver type for host.
> + */
> +void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type)
> +{
> + host->ios.drv_type = drv_type;
> + mmc_set_ios(host);
> +}
> +
> +/*
> * Apply power to the MMC stack. This is a two-stage process.
> * First, we enable power to the card without the clock running.
> * We then wait a bit for the power to stabilise. Finally,
> diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
> index ca1fdde..6114ca5 100644
> --- a/drivers/mmc/core/core.h
> +++ b/drivers/mmc/core/core.h
> @@ -42,6 +42,7 @@ void mmc_set_bus_width_ddr(struct mmc_host *host,
> unsigned int width,
> unsigned int ddr);
> u32 mmc_select_voltage(struct mmc_host *host, u32 ocr);
> void mmc_set_timing(struct mmc_host *host, unsigned int timing);
> +void mmc_set_driver_type(struct mmc_host *host, unsigned int
> drv_type);
>
> static inline void mmc_delay(unsigned int ms)
> {
> diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
> index a63956b..f6a4fab 100644
> --- a/drivers/mmc/core/sd.c
> +++ b/drivers/mmc/core/sd.c
> @@ -426,6 +426,86 @@ out:
> return err;
> }
>
> +static int sd_select_driver_type(struct mmc_card *card, u8 *status)
> +{
> + int host_set_drv_type, card_set_drv_type;
Why you need to use *set* in name? Just host_drv_type & card_drv_type is not
enough?
> + int err;
> +
> + /*
> + * If the host doesn't support any of the Driver Types A,C or D,
> + * default Driver Type B is used.
> + */
> + if (!(card->host->caps & (MMC_CAP_DRIVER_TYPE_A |
> MMC_CAP_DRIVER_TYPE_C
> + | MMC_CAP_DRIVER_TYPE_D)))
> + return 0;
> +
> + if (card->host->caps & MMC_CAP_DRIVER_TYPE_A) {
> + host_set_drv_type = MMC_SET_DRIVER_TYPE_A;
> + if (card->sw_caps.uhs_drv_type & SD_DRIVER_TYPE_A)
> + card_set_drv_type = MMC_SET_DRIVER_TYPE_A;
> + else if (card->sw_caps.uhs_drv_type & SD_DRIVER_TYPE_C)
> + card_set_drv_type = MMC_SET_DRIVER_TYPE_C;
Why you are combining TYPE_C under CAP_*_TYPE_A?
> + } else if (card->host->caps & MMC_CAP_DRIVER_TYPE_C) {
> + host_set_drv_type = MMC_SET_DRIVER_TYPE_C;
> + if (card->sw_caps.uhs_drv_type & SD_DRIVER_TYPE_C)
> + card_set_drv_type = MMC_SET_DRIVER_TYPE_C;
> + }
Again TYPE_C checking here? Also why are you skiping TYPE_D here?
> +
> + err = mmc_sd_switch(card, 1, 2, card_set_drv_type, status);
> + if (err)
> + return err;
> +
> + if ((status[15] & 0xF) != card_set_drv_type)
> + printk(KERN_WARNING "%s: Problem setting driver
> strength!\n",
> + mmc_hostname(card->host));
> + else
> + mmc_set_driver_type(card->host, host_set_drv_type);
> +
> + return 0;
> +}
> +
> +/*
> + * UHS-I specific initialization procedure
> + */
> +static int mmc_sd_init_uhs_card(struct mmc_card *card)
> +{
> + int err;
> + u8 *status;
> +
> + if (!card->scr.sda_spec3)
> + return 0;
> +
> + if (!(card->csd.cmdclass & CCC_SWITCH))
> + return 0;
We can combine both these check under single "if" checking.
> +
> + err = -EIO;
Is this really required? I don't think initializing "err" is needed here.
> +
> + status = kmalloc(64, GFP_KERNEL);
> + if (!status) {
> + printk(KERN_ERR "%s: could not allocate a buffer for "
> + "switch capabilities.\n", mmc_hostname(card->host));
> + return -ENOMEM;
> + }
You may want to allocate memory only after bus width setting is successful.
> +
> + /* Set 4-bit bus width */
> + if ((card->host->caps & MMC_CAP_4_BIT_DATA) &&
> + (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
> + err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
> + if (err)
> + goto out;
> +
> + mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
> + }
> +
> + /* Set the driver strength for the card */
> + err = sd_select_driver_type(card, status);
Actually why are you allocating memory for "status" response in
mmc_sd_init_uhs_card() function. You need "status" only in
sd_select_driver_type() function. So you should be allocating memory in
sd_select_driver_type() function only. here you just say "
sd_select_driver_type(card);"
> +
> +out:
> + kfree(status);
> +
> + return err;
> +}
> +
> MMC_DEV_ATTR(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card-
> >raw_cid[1],
> card->raw_cid[2], card->raw_cid[3]);
> MMC_DEV_ATTR(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card-
> >raw_csd[1],
> @@ -474,10 +554,10 @@ struct device_type sd_type = {
> /*
> * Fetch CID from card.
> */
> -int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid)
> +int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid,
> + u32 *rocr)
> {
> int err;
> - u32 rocr;
>
> /*
> * Since we're changing the OCR value, we seem to
> @@ -502,7 +582,7 @@ int mmc_sd_get_cid(struct mmc_host *host, u32 ocr,
> u32 *cid)
> MMC_CAP_SET_XPC_180))
> ocr |= 1 << 28;
>
> - err = mmc_send_app_op_cond(host, ocr, &rocr);
> + err = mmc_send_app_op_cond(host, ocr, rocr);
> if (err)
> return err;
>
> @@ -510,7 +590,7 @@ int mmc_sd_get_cid(struct mmc_host *host, u32 ocr,
> u32 *cid)
> * In case CCS and S18A in the response is set, start Signal
> Voltage
> * Switch procedure. SPI mode doesn't support CMD11.
> */
> - if (!mmc_host_is_spi(host) && (rocr & 0x41000000)) {
> + if (!mmc_host_is_spi(host) && rocr && (*rocr & 0x41000000)) {
You are not doing NULL check for "rocr" in mmc_send_app_op_cond() but you
are doing it here. Is it needed? If "rocr" is NULL then
mmc_send_app_op_cond() itself will fail.
Also, you may need to check b31 (busy bit) of rocr because spec says this:
"Section:4.2.3.1 CCS (Bit 30) and S18A (Bit 24) are valid when Busy (Bit 31)
is set to 1."
> err = mmc_start_voltage_switch(host);
> if (err)
> return err;
> @@ -643,11 +723,12 @@ static int mmc_sd_init_card(struct mmc_host
> *host, u32 ocr,
> struct mmc_card *card;
> int err;
> u32 cid[4];
> + u32 rocr;
>
> BUG_ON(!host);
> WARN_ON(!host->claimed);
>
> - err = mmc_sd_get_cid(host, ocr, cid);
> + err = mmc_sd_get_cid(host, ocr, cid, &rocr);
> if (err)
> return err;
>
> @@ -700,30 +781,37 @@ static int mmc_sd_init_card(struct mmc_host
> *host, u32 ocr,
> if (err)
> goto free_card;
>
> - /*
> - * Attempt to change to high-speed (if supported)
> - */
> - err = mmc_sd_switch_hs(card);
> - if (err > 0)
> - mmc_sd_go_highspeed(card);
> - else if (err)
> - goto free_card;
> -
> - /*
> - * Set bus speed.
> - */
> - mmc_set_clock(host, mmc_sd_get_max_clock(card));
> -
> - /*
> - * Switch to wider bus (if supported).
> - */
> - if ((host->caps & MMC_CAP_4_BIT_DATA) &&
> - (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
> - err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
> + /* Initialization sequence for UHS-I cards */
> + if (rocr & 0x01000000) {
Instead of 0x01000000, you can use (1 << 24) to be more readable.
> + err = mmc_sd_init_uhs_card(card);
> if (err)
> goto free_card;
> + } else {
> + /*
> + * Attempt to change to high-speed (if supported)
> + */
> + err = mmc_sd_switch_hs(card);
> + if (err > 0)
> + mmc_sd_go_highspeed(card);
> + else if (err)
> + goto free_card;
> +
> + /*
> + * Set bus speed.
> + */
> + mmc_set_clock(host, mmc_sd_get_max_clock(card));
>
> - mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
> + /*
> + * Switch to wider bus (if supported).
> + */
> + if ((host->caps & MMC_CAP_4_BIT_DATA) &&
> + (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
> + err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
> + if (err)
> + goto free_card;
> +
> + mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
> + }
> }
>
> host->card = card;
> diff --git a/drivers/mmc/core/sd.h b/drivers/mmc/core/sd.h
> index 3d8800f..5106b44 100644
> --- a/drivers/mmc/core/sd.h
> +++ b/drivers/mmc/core/sd.h
> @@ -5,7 +5,8 @@
>
> extern struct device_type sd_type;
>
> -int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid);
> +int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid,
> + u32 *rocr);
> int mmc_sd_get_csd(struct mmc_host *host, struct mmc_card *card);
> void mmc_decode_cid(struct mmc_card *card);
> int mmc_sd_setup_card(struct mmc_host *host, struct mmc_card *card,
> diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
> index 5c4a54d..6d16684 100644
> --- a/drivers/mmc/core/sdio.c
> +++ b/drivers/mmc/core/sdio.c
> @@ -364,7 +364,8 @@ static int mmc_sdio_init_card(struct mmc_host
> *host, u32 ocr,
> }
>
> if (ocr & R4_MEMORY_PRESENT
> - && mmc_sd_get_cid(host, host->ocr & ocr, card->raw_cid) == 0)
> {
> + && mmc_sd_get_cid(host, host->ocr & ocr, card->raw_cid,
> + NULL) == 0) {
> card->type = MMC_TYPE_SD_COMBO;
>
> if (oldcard && (oldcard->type != MMC_TYPE_SD_COMBO ||
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 5487a0b..1645687 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -63,7 +63,7 @@ static void sdhci_dumpregs(struct sdhci_host *host)
> sdhci_readw(host, SDHCI_TRANSFER_MODE));
> printk(KERN_DEBUG DRIVER_NAME ": Present: 0x%08x | Host ctl:
> 0x%08x\n",
> sdhci_readl(host, SDHCI_PRESENT_STATE),
> - sdhci_readb(host, SDHCI_HOST_CONTROL));
> + sdhci_readb(host, SDHCI_HOST_CONTROL1));
> printk(KERN_DEBUG DRIVER_NAME ": Power: 0x%08x | Blk gap:
> 0x%08x\n",
> sdhci_readb(host, SDHCI_POWER_CONTROL),
> sdhci_readb(host, SDHCI_BLOCK_GAP_CONTROL));
> @@ -216,18 +216,18 @@ static void sdhci_activate_led(struct sdhci_host
> *host)
> {
> u8 ctrl;
>
> - ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
> + ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL1);
> ctrl |= SDHCI_CTRL_LED;
> - sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
> + sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL1);
> }
>
> static void sdhci_deactivate_led(struct sdhci_host *host)
> {
> u8 ctrl;
>
> - ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
> + ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL1);
> ctrl &= ~SDHCI_CTRL_LED;
> - sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
> + sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL1);
> }
>
> #ifdef SDHCI_USE_LEDS_CLASS
> @@ -786,14 +786,14 @@ static void sdhci_prepare_data(struct sdhci_host
> *host, struct mmc_data *data)
> * is ADMA.
> */
> if (host->version >= SDHCI_SPEC_200) {
> - ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
> + ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL1);
> ctrl &= ~SDHCI_CTRL_DMA_MASK;
> if ((host->flags & SDHCI_REQ_USE_DMA) &&
> (host->flags & SDHCI_USE_ADMA))
> ctrl |= SDHCI_CTRL_ADMA32;
> else
> ctrl |= SDHCI_CTRL_SDMA;
> - sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
> + sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL1);
> }
>
> if (!(host->flags & SDHCI_REQ_USE_DMA)) {
> @@ -1252,7 +1252,7 @@ static void sdhci_set_ios(struct mmc_host *mmc,
> struct mmc_ios *ios)
> if (host->ops->platform_8bit_width)
> host->ops->platform_8bit_width(host, ios->bus_width);
> else {
> - ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
> + ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL1);
> if (ios->bus_width == MMC_BUS_WIDTH_8) {
> ctrl &= ~SDHCI_CTRL_4BITBUS;
> if (host->version >= SDHCI_SPEC_300)
> @@ -1265,10 +1265,10 @@ static void sdhci_set_ios(struct mmc_host *mmc,
> struct mmc_ios *ios)
> else
> ctrl &= ~SDHCI_CTRL_4BITBUS;
> }
> - sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
> + sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL1);
> }
>
> - ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
> + ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL1);
>
> if ((ios->timing == MMC_TIMING_SD_HS ||
> ios->timing == MMC_TIMING_MMC_HS)
> @@ -1277,7 +1277,25 @@ static void sdhci_set_ios(struct mmc_host *mmc,
> struct mmc_ios *ios)
> else
> ctrl &= ~SDHCI_CTRL_HISPD;
>
> - sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
> + sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL1);
> +
> + if (host->version >= SDHCI_SPEC_300) {
> + u16 ctrl_2;
> +
> + ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
> + if (!(ctrl_2 & SDHCI_CTRL_PRESET_VAL_ENABLE)) {
> + /*
> + * We only need to set Driver Strength if the
> + * preset value enable is not set.
> + */
> + if (ios->drv_type == MMC_SET_DRIVER_TYPE_A)
> + ctrl_2 |= SDHCI_CTRL_DRV_TYPE_A;
> + else if (ios->drv_type == MMC_SET_DRIVER_TYPE_C)
> + ctrl_2 |= SDHCI_CTRL_DRV_TYPE_C;
> +
> + sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
> + }
> + }
>
> /*
> * Some (ENE) controllers go apeshit on some ios operation,
> @@ -2037,6 +2055,14 @@ int sdhci_add_host(struct sdhci_host *host)
> if (caps[1] & SDHCI_SUPPORT_DDR50)
> mmc->caps |= MMC_CAP_UHS_DDR50;
>
> + /* Driver Type(s) (A, C, D) supported by the host */
> + if (caps[1] & SDHCI_DRIVER_TYPE_A)
> + mmc->caps |= MMC_CAP_DRIVER_TYPE_A;
> + if (caps[1] & SDHCI_DRIVER_TYPE_C)
> + mmc->caps |= MMC_CAP_DRIVER_TYPE_C;
> + if (caps[1] & SDHCI_DRIVER_TYPE_D)
> + mmc->caps |= MMC_CAP_DRIVER_TYPE_D;
> +
> ocr_avail = 0;
> /*
> * According to SD Host Controller spec v3.00, if the Host System
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index 95d70e6..a407b5b 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -72,7 +72,7 @@
> #define SDHCI_DATA_LVL_MASK 0x00F00000
> #define SDHCI_DATA_LVL_SHIFT 20
>
> -#define SDHCI_HOST_CONTROL 0x28
> +#define SDHCI_HOST_CONTROL1 0x28
> #define SDHCI_CTRL_LED 0x01
> #define SDHCI_CTRL_4BITBUS 0x02
> #define SDHCI_CTRL_HISPD 0x04
> @@ -151,6 +151,11 @@
>
> #define SDHCI_HOST_CONTROL2 0x3E
> #define SDHCI_CTRL_VDD_180 0x0008
> +#define SDHCI_CTRL_DRV_TYPE_B 0x0000
> +#define SDHCI_CTRL_DRV_TYPE_A 0x0010
> +#define SDHCI_CTRL_DRV_TYPE_C 0x0020
> +#define SDHCI_CTRL_DRV_TYPE_D 0x0030
> +#define SDHCI_CTRL_PRESET_VAL_ENABLE 0x8000
>
> #define SDHCI_CAPABILITIES 0x40
> #define SDHCI_TIMEOUT_CLK_MASK 0x0000003F
> @@ -174,6 +179,9 @@
> #define SDHCI_SUPPORT_SDR50 0x00000001
> #define SDHCI_SUPPORT_SDR104 0x00000002
> #define SDHCI_SUPPORT_DDR50 0x00000004
> +#define SDHCI_DRIVER_TYPE_A 0x00000010
> +#define SDHCI_DRIVER_TYPE_C 0x00000020
> +#define SDHCI_DRIVER_TYPE_D 0x00000040
>
> #define SDHCI_CAPABILITIES_1 0x44
>
> diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
> index 7080f22..2d7f7a3 100644
> --- a/include/linux/mmc/card.h
> +++ b/include/linux/mmc/card.h
> @@ -77,6 +77,10 @@ struct sd_switch_caps {
> unsigned int hs_max_dtr;
> unsigned int uhs_bus_mode;
> unsigned int uhs_drv_type;
> +#define SD_DRIVER_TYPE_B 0x01
> +#define SD_DRIVER_TYPE_A 0x02
> +#define SD_DRIVER_TYPE_C 0x04
> +#define SD_DRIVER_TYPE_D 0x08
> unsigned int uhs_curr_limit;
> };
>
> diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
> index ad7daa3..bc2121e 100644
> --- a/include/linux/mmc/host.h
> +++ b/include/linux/mmc/host.h
> @@ -56,6 +56,11 @@ struct mmc_ios {
> #define MMC_SDR_MODE 0
> #define MMC_1_2V_DDR_MODE 1
> #define MMC_1_8V_DDR_MODE 2
> +
> + unsigned char drv_type; /* driver type (A, C, D) */
> +
> +#define MMC_SET_DRIVER_TYPE_A 1
> +#define MMC_SET_DRIVER_TYPE_C 2
*SET* is not required in name. again why are we ignoring TYPE D here?
> };
>
> struct mmc_host_ops {
> @@ -183,6 +188,9 @@ struct mmc_host {
> #define MMC_CAP_SET_XPC_330 (1 << 20) /* Host supports >150mA
> current at 3.3V */
> #define MMC_CAP_SET_XPC_300 (1 << 21) /* Host supports >150mA
> current at 3.0V */
> #define MMC_CAP_SET_XPC_180 (1 << 22) /* Host supports >150mA
> current at 1.8V */
> +#define MMC_CAP_DRIVER_TYPE_A (1 << 23) /* Host supports
Driver
> Type A */
> +#define MMC_CAP_DRIVER_TYPE_C (1 << 24) /* Host supports
Driver
> Type C */
> +#define MMC_CAP_DRIVER_TYPE_D (1 << 25) /* Host supports
Driver
> Type D */
>
> mmc_pm_flag_t pm_caps; /* supported pm features */
>
> --
> 1.7.1
>
> --
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