diff mbox

mmc: sdhci-msm: Optionally wait for signal level changes

Message ID 20171120183451.18966-1-bjorn.andersson@linaro.org (mailing list archive)
State New, archived
Headers show

Commit Message

Bjorn Andersson Nov. 20, 2017, 6:34 p.m. UTC
Not all instances of the SDCC core supports changing signal voltage and
as such will not generate a power interrupt when the software attempts
to change the voltage. This results in probing the eMMC on some devices
to take over 2 minutes.

Check that the SWITCHABLE_SIGNAL_VOLTAGE bit in MCI_GENERICS is set
before waiting for the power interrupt.

Cc: Sahitya Tummala <stummala@codeaurora.org>
Cc: Vijay Viswanath <vviswana@codeaurora.org>
Fixes: c0309b3803fe ("mmc: sdhci-msm: Add sdhci msm register write APIs which wait for pwr irq")
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
---

The offending patch is part of your v4.15 pull request, so please pick
this up for the -rcs.

 drivers/mmc/host/sdhci-msm.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

Comments

Stephen Boyd Nov. 20, 2017, 7:25 p.m. UTC | #1
On 11/20, Bjorn Andersson wrote:
> Not all instances of the SDCC core supports changing signal voltage and
> as such will not generate a power interrupt when the software attempts
> to change the voltage. This results in probing the eMMC on some devices
> to take over 2 minutes.
> 
> Check that the SWITCHABLE_SIGNAL_VOLTAGE bit in MCI_GENERICS is set

T in SWITCHABLE_SIGNAL_VOLTAGE here.

> before waiting for the power interrupt.
> 
> Cc: Sahitya Tummala <stummala@codeaurora.org>
> Cc: Vijay Viswanath <vviswana@codeaurora.org>
> Fixes: c0309b3803fe ("mmc: sdhci-msm: Add sdhci msm register write APIs which wait for pwr irq")
> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
> ---
> 
> The offending patch is part of your v4.15 pull request, so please pick
> this up for the -rcs.
> 
>  drivers/mmc/host/sdhci-msm.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index 3fb7d2eec93f..8f2dda73e6b4 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -29,6 +29,9 @@
>  #define CORE_VERSION_MAJOR_MASK		(0xf << CORE_VERSION_MAJOR_SHIFT)
>  #define CORE_VERSION_MINOR_MASK		0xff
>  
> +#define CORE_MCI_GENERICS		0x70
> +#define SWICHABLE_SIGNALING_VOLTAGE	BIT(29)

But then the T isn't here.
diff mbox

Patch

diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
index 3fb7d2eec93f..8f2dda73e6b4 100644
--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -29,6 +29,9 @@ 
 #define CORE_VERSION_MAJOR_MASK		(0xf << CORE_VERSION_MAJOR_SHIFT)
 #define CORE_VERSION_MINOR_MASK		0xff
 
+#define CORE_MCI_GENERICS		0x70
+#define SWICHABLE_SIGNALING_VOLTAGE	BIT(29)
+
 #define CORE_HC_MODE		0x78
 #define HC_MODE_EN		0x1
 #define CORE_POWER		0x0
@@ -1028,11 +1031,22 @@  static void sdhci_msm_check_power_status(struct sdhci_host *host, u32 req_type)
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
 	bool done = false;
+	u32 val;
 
 	pr_debug("%s: %s: request %d curr_pwr_state %x curr_io_level %x\n",
 			mmc_hostname(host->mmc), __func__, req_type,
 			msm_host->curr_pwr_state, msm_host->curr_io_level);
 
+	/*
+	 * The power interrupt will not be generated for signal voltage
+	 * switches if SWICHABLE_SIGNALING_VOLTAGE in MCI_GENERICS is not set
+	 */
+	val = readl(msm_host->core_mem + CORE_MCI_GENERICS);
+	if ((req_type & REQ_IO_HIGH || req_type & REQ_IO_LOW) &&
+	    !(val & SWICHABLE_SIGNALING_VOLTAGE)) {
+		return;
+	}
+
 	/*
 	 * The IRQ for request type IO High/LOW will be generated when -
 	 * there is a state change in 1.8V enable bit (bit 3) of