| Message ID | 1491887431-31894-3-git-send-email-yangbo.lu@nxp.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On 11/04/17 08:10, Yangbo Lu wrote: > eSDHC supports signal voltage switch from 3.3v to 1.8v by > eSDHC_PROCTL[VOLT_SEL] bit. This bit changes the value of output > signal SDHC_VS, and there must be a control circuit out of eSDHC > to change the signal voltage according to SDHC_VS output signal. > > Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com> Acked-by: Adrian Hunter <adrian.hunter@intel.com> > --- > Changes for v2: > - Used Adrain's method to support voltage switching: > host->mmc_host_ops.start_signal_voltage_switch = > esdhc_signal_voltage_switch; > Changes for v3: > - Put .start_signal_voltage_switch assigning after IS_ERR(host) check. > Changes for v4: > - None > --- > drivers/mmc/host/sdhci-esdhc.h | 1 + > drivers/mmc/host/sdhci-of-esdhc.c | 74 +++++++++++++++++++++++++++++++++++++++ > 2 files changed, 75 insertions(+) > > diff --git a/drivers/mmc/host/sdhci-esdhc.h b/drivers/mmc/host/sdhci-esdhc.h > index 5343fc0..6869567 100644 > --- a/drivers/mmc/host/sdhci-esdhc.h > +++ b/drivers/mmc/host/sdhci-esdhc.h > @@ -37,6 +37,7 @@ > > /* Protocol Control Register */ > #define ESDHC_PROCTL 0x28 > +#define ESDHC_VOLT_SEL 0x00000400 > #define ESDHC_CTRL_4BITBUS (0x1 << 1) > #define ESDHC_CTRL_8BITBUS (0x2 << 1) > #define ESDHC_CTRL_BUSWIDTH_MASK (0x3 << 1) > diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-of-esdhc.c > index 6d024b6..4dd28c3 100644 > --- a/drivers/mmc/host/sdhci-of-esdhc.c > +++ b/drivers/mmc/host/sdhci-of-esdhc.c > @@ -16,6 +16,7 @@ > #include <linux/err.h> > #include <linux/io.h> > #include <linux/of.h> > +#include <linux/of_address.h> > #include <linux/delay.h> > #include <linux/module.h> > #include <linux/sys_soc.h> > @@ -559,6 +560,76 @@ static void esdhc_reset(struct sdhci_host *host, u8 mask) > sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE); > } > > +/* The SCFG, Supplemental Configuration Unit, provides SoC specific > + * configuration and status registers for the device. There is a > + * SDHC IO VSEL control register on SCFG for some platforms. It's > + * used to support SDHC IO voltage switching. > + */ > +static const struct of_device_id scfg_device_ids[] = { > + { .compatible = "fsl,t1040-scfg", }, > + { .compatible = "fsl,ls1012a-scfg", }, > + { .compatible = "fsl,ls1046a-scfg", }, > + {} > +}; > + > +/* SDHC IO VSEL control register definition */ > +#define SCFG_SDHCIOVSELCR 0x408 > +#define SDHCIOVSELCR_TGLEN 0x80000000 > +#define SDHCIOVSELCR_VSELVAL 0x60000000 > +#define SDHCIOVSELCR_SDHC_VS 0x00000001 > + > +static int esdhc_signal_voltage_switch(struct mmc_host *mmc, > + struct mmc_ios *ios) > +{ > + struct sdhci_host *host = mmc_priv(mmc); > + struct device_node *scfg_node; > + void __iomem *scfg_base = NULL; > + u32 sdhciovselcr; > + u32 val; > + > + /* > + * Signal Voltage Switching is only applicable for Host Controllers > + * v3.00 and above. > + */ > + if (host->version < SDHCI_SPEC_300) > + return 0; > + > + val = sdhci_readl(host, ESDHC_PROCTL); > + > + switch (ios->signal_voltage) { > + case MMC_SIGNAL_VOLTAGE_330: > + val &= ~ESDHC_VOLT_SEL; > + sdhci_writel(host, val, ESDHC_PROCTL); > + return 0; > + case MMC_SIGNAL_VOLTAGE_180: > + scfg_node = of_find_matching_node(NULL, scfg_device_ids); > + if (scfg_node) > + scfg_base = of_iomap(scfg_node, 0); > + if (scfg_base) { > + sdhciovselcr = SDHCIOVSELCR_TGLEN | > + SDHCIOVSELCR_VSELVAL; > + iowrite32be(sdhciovselcr, > + scfg_base + SCFG_SDHCIOVSELCR); > + > + val |= ESDHC_VOLT_SEL; > + sdhci_writel(host, val, ESDHC_PROCTL); > + mdelay(5); > + > + sdhciovselcr = SDHCIOVSELCR_TGLEN | > + SDHCIOVSELCR_SDHC_VS; > + iowrite32be(sdhciovselcr, > + scfg_base + SCFG_SDHCIOVSELCR); > + iounmap(scfg_base); > + } else { > + val |= ESDHC_VOLT_SEL; > + sdhci_writel(host, val, ESDHC_PROCTL); > + } > + return 0; > + default: > + return 0; > + } > +} > + > #ifdef CONFIG_PM_SLEEP > static u32 esdhc_proctl; > static int esdhc_of_suspend(struct device *dev) > @@ -716,6 +787,9 @@ static int sdhci_esdhc_probe(struct platform_device *pdev) > if (IS_ERR(host)) > return PTR_ERR(host); > > + host->mmc_host_ops.start_signal_voltage_switch = > + esdhc_signal_voltage_switch; > + > esdhc_init(pdev, host); > > sdhci_get_of_property(pdev); > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/mmc/host/sdhci-esdhc.h b/drivers/mmc/host/sdhci-esdhc.h index 5343fc0..6869567 100644 --- a/drivers/mmc/host/sdhci-esdhc.h +++ b/drivers/mmc/host/sdhci-esdhc.h @@ -37,6 +37,7 @@ /* Protocol Control Register */ #define ESDHC_PROCTL 0x28 +#define ESDHC_VOLT_SEL 0x00000400 #define ESDHC_CTRL_4BITBUS (0x1 << 1) #define ESDHC_CTRL_8BITBUS (0x2 << 1) #define ESDHC_CTRL_BUSWIDTH_MASK (0x3 << 1) diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-of-esdhc.c index 6d024b6..4dd28c3 100644 --- a/drivers/mmc/host/sdhci-of-esdhc.c +++ b/drivers/mmc/host/sdhci-of-esdhc.c @@ -16,6 +16,7 @@ #include <linux/err.h> #include <linux/io.h> #include <linux/of.h> +#include <linux/of_address.h> #include <linux/delay.h> #include <linux/module.h> #include <linux/sys_soc.h> @@ -559,6 +560,76 @@ static void esdhc_reset(struct sdhci_host *host, u8 mask) sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE); } +/* The SCFG, Supplemental Configuration Unit, provides SoC specific + * configuration and status registers for the device. There is a + * SDHC IO VSEL control register on SCFG for some platforms. It's + * used to support SDHC IO voltage switching. + */ +static const struct of_device_id scfg_device_ids[] = { + { .compatible = "fsl,t1040-scfg", }, + { .compatible = "fsl,ls1012a-scfg", }, + { .compatible = "fsl,ls1046a-scfg", }, + {} +}; + +/* SDHC IO VSEL control register definition */ +#define SCFG_SDHCIOVSELCR 0x408 +#define SDHCIOVSELCR_TGLEN 0x80000000 +#define SDHCIOVSELCR_VSELVAL 0x60000000 +#define SDHCIOVSELCR_SDHC_VS 0x00000001 + +static int esdhc_signal_voltage_switch(struct mmc_host *mmc, + struct mmc_ios *ios) +{ + struct sdhci_host *host = mmc_priv(mmc); + struct device_node *scfg_node; + void __iomem *scfg_base = NULL; + u32 sdhciovselcr; + u32 val; + + /* + * Signal Voltage Switching is only applicable for Host Controllers + * v3.00 and above. + */ + if (host->version < SDHCI_SPEC_300) + return 0; + + val = sdhci_readl(host, ESDHC_PROCTL); + + switch (ios->signal_voltage) { + case MMC_SIGNAL_VOLTAGE_330: + val &= ~ESDHC_VOLT_SEL; + sdhci_writel(host, val, ESDHC_PROCTL); + return 0; + case MMC_SIGNAL_VOLTAGE_180: + scfg_node = of_find_matching_node(NULL, scfg_device_ids); + if (scfg_node) + scfg_base = of_iomap(scfg_node, 0); + if (scfg_base) { + sdhciovselcr = SDHCIOVSELCR_TGLEN | + SDHCIOVSELCR_VSELVAL; + iowrite32be(sdhciovselcr, + scfg_base + SCFG_SDHCIOVSELCR); + + val |= ESDHC_VOLT_SEL; + sdhci_writel(host, val, ESDHC_PROCTL); + mdelay(5); + + sdhciovselcr = SDHCIOVSELCR_TGLEN | + SDHCIOVSELCR_SDHC_VS; + iowrite32be(sdhciovselcr, + scfg_base + SCFG_SDHCIOVSELCR); + iounmap(scfg_base); + } else { + val |= ESDHC_VOLT_SEL; + sdhci_writel(host, val, ESDHC_PROCTL); + } + return 0; + default: + return 0; + } +} + #ifdef CONFIG_PM_SLEEP static u32 esdhc_proctl; static int esdhc_of_suspend(struct device *dev) @@ -716,6 +787,9 @@ static int sdhci_esdhc_probe(struct platform_device *pdev) if (IS_ERR(host)) return PTR_ERR(host); + host->mmc_host_ops.start_signal_voltage_switch = + esdhc_signal_voltage_switch; + esdhc_init(pdev, host); sdhci_get_of_property(pdev);
eSDHC supports signal voltage switch from 3.3v to 1.8v by eSDHC_PROCTL[VOLT_SEL] bit. This bit changes the value of output signal SDHC_VS, and there must be a control circuit out of eSDHC to change the signal voltage according to SDHC_VS output signal. Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com> --- Changes for v2: - Used Adrain's method to support voltage switching: host->mmc_host_ops.start_signal_voltage_switch = esdhc_signal_voltage_switch; Changes for v3: - Put .start_signal_voltage_switch assigning after IS_ERR(host) check. Changes for v4: - None --- drivers/mmc/host/sdhci-esdhc.h | 1 + drivers/mmc/host/sdhci-of-esdhc.c | 74 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 75 insertions(+)