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mmc: mmci_sdmmc: Implement signal voltage callbacks

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To prepare the voltage switch procedure, the VSWITCHEN bit must be set
before sending the CMD11. To confirm completion of voltage switch, the
VSWEND flag must be checked.

Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Link: https://lore.kernel.org/r/20200128090636.13689-9-ludovic.barre@st.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Ludovic Barre 2020-01-28 10:06:35 +01:00 committed by Ulf Hansson
parent 7577316528
commit 94b94a93e3
2 changed files with 47 additions and 0 deletions
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4
drivers/mmc/host/mmci.h
View file

@ -165,6 +165,7 @@
/* Extended status bits for the STM32 variants */
#define MCI_STM32_BUSYD0 BIT(20)
#define MCI_STM32_BUSYD0END BIT(21)
#define MCI_STM32_VSWEND BIT(25)
#define MMCICLEAR 0x038
#define MCI_CMDCRCFAILCLR (1 << 0)
@ -182,6 +183,9 @@
#define MCI_ST_SDIOITC (1 << 22)
#define MCI_ST_CEATAENDC (1 << 23)
#define MCI_ST_BUSYENDC (1 << 24)
/* Extended clear bits for the STM32 variants */
#define MCI_STM32_VSWENDC BIT(25)
#define MCI_STM32_CKSTOPC BIT(26)
#define MMCIMASK0 0x03c
#define MCI_CMDCRCFAILMASK (1 << 0)

43
drivers/mmc/host/mmci_stm32_sdmmc.c
View file

@ -32,6 +32,7 @@
#define DLYB_CFGR_UNIT_MAX 127
#define DLYB_LNG_TIMEOUT_US 1000
#define SDMMC_VSWEND_TIMEOUT_US 10000
struct sdmmc_lli_desc {
u32 idmalar;
@ -265,6 +266,7 @@ static void mmci_sdmmc_set_pwrreg(struct mmci_host *host, unsigned int pwr)
struct mmc_ios ios = host->mmc->ios;
struct sdmmc_dlyb *dlyb = host->variant_priv;
/* adds OF options */
pwr = host->pwr_reg_add;
sdmmc_dlyb_input_ck(dlyb);
@ -291,6 +293,10 @@ static void mmci_sdmmc_set_pwrreg(struct mmci_host *host, unsigned int pwr)
writel(MCI_IRQENABLE | host->variant->start_err,
host->base + MMCIMASK0);
/* preserves voltage switch bits */
pwr |= host->pwr_reg & (MCI_STM32_VSWITCHEN |
MCI_STM32_VSWITCH);
/*
* After a power-cycle state, we must set the SDMMC in
* Power-off. The SDMMC_D[7:0], SDMMC_CMD and SDMMC_CK are
@ -456,6 +462,41 @@ static int sdmmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
return sdmmc_dlyb_phase_tuning(host, opcode);
}
static void sdmmc_pre_sig_volt_vswitch(struct mmci_host *host)
{
/* clear the voltage switch completion flag */
writel_relaxed(MCI_STM32_VSWENDC, host->base + MMCICLEAR);
/* enable Voltage switch procedure */
mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCHEN);
}
static int sdmmc_post_sig_volt_switch(struct mmci_host *host,
struct mmc_ios *ios)
{
unsigned long flags;
u32 status;
int ret = 0;
if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180) {
spin_lock_irqsave(&host->lock, flags);
mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCH);
spin_unlock_irqrestore(&host->lock, flags);
/* wait voltage switch completion while 10ms */
ret = readl_relaxed_poll_timeout(host->base + MMCISTATUS,
status,
(status & MCI_STM32_VSWEND),
10, SDMMC_VSWEND_TIMEOUT_US);
writel_relaxed(MCI_STM32_VSWENDC | MCI_STM32_CKSTOPC,
host->base + MMCICLEAR);
mmci_write_pwrreg(host, host->pwr_reg &
~(MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH));
}
return ret;
}
static struct mmci_host_ops sdmmc_variant_ops = {
.validate_data = sdmmc_idma_validate_data,
.prep_data = sdmmc_idma_prep_data,
@ -467,6 +508,8 @@ static struct mmci_host_ops sdmmc_variant_ops = {
.set_clkreg = mmci_sdmmc_set_clkreg,
.set_pwrreg = mmci_sdmmc_set_pwrreg,
.busy_complete = sdmmc_busy_complete,
.pre_sig_volt_switch = sdmmc_pre_sig_volt_vswitch,
.post_sig_volt_switch = sdmmc_post_sig_volt_switch,
};
void sdmmc_variant_init(struct mmci_host *host)