hi Ulf Le 1/24/20 à 2:16 PM, Ulf Hansson a écrit :
On Fri, 10 Jan 2020 at 14:49, Ludovic Barre <ludovic.barre@xxxxxx> wrote: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@xxxxxx> --- drivers/mmc/host/mmci.h | 4 +++ drivers/mmc/host/mmci_stm32_sdmmc.c | 40 ++++++++++++++++++++++++++++- 2 files changed, 43 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h index c04a144259a2..3634f98ad2d8 100644 --- a/drivers/mmc/host/mmci.h +++ b/drivers/mmc/host/mmci.h @@ -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) diff --git a/drivers/mmc/host/mmci_stm32_sdmmc.c b/drivers/mmc/host/mmci_stm32_sdmmc.c index 10059fa19f4a..9f43cf947c5f 100644 --- a/drivers/mmc/host/mmci_stm32_sdmmc.c +++ b/drivers/mmc/host/mmci_stm32_sdmmc.c @@ -263,7 +263,9 @@ 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; - pwr = host->pwr_reg_add; + /* adds OF options and preserves voltage switch bits */ + pwr = host->pwr_reg_add | + (host->pwr_reg & (MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH)); sdmmc_dlyb_input_ck(dlyb); @@ -454,6 +456,40 @@ static int sdmmc_execute_tuning(struct mmc_host *mmc, u32 opcode) return sdmmc_dlyb_phase_tuning(host, opcode); } +static void sdmmc_prep_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_vswitch(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, 10000); + + writel_relaxed(MCI_STM32_VSWENDC | MCI_STM32_CKSTOPC, + host->base + MMCICLEAR); + mmci_write_pwrreg(host, host->pwr_reg & + ~(MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH)); + }Don't you need to manage things when resetting to MMC_SIGNAL_VOLTAGE_330, which for example happens during a card removal or at system suspend/resume?
The VSWITCH sequence is used only for 3.3V to 1.8V. If there are: card remove | suspend/resume. The power cycle of sdmmc must be reinitialised and the reset is mandatory.
+ + return ret; +} + static struct mmci_host_ops sdmmc_variant_ops = { .validate_data = sdmmc_idma_validate_data, .prep_data = sdmmc_idma_prep_data, @@ -465,6 +501,8 @@ 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, + .prep_volt_switch = sdmmc_prep_vswitch, + .volt_switch = sdmmc_vswitch, }; void sdmmc_variant_init(struct mmci_host *host) -- 2.17.1Kind regards Uffe
