LKML Archive on lore.kernel.org
 help / color / Atom feed
From: Luca Weiss <luca@z3ntu.xyz>
To: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>,
	Ulf Hansson <ulf.hansson@linaro.org>,
	linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-arm-msm@vger.kernel.org,
	Stephen Boyd <sboyd@codeaurora.org>,
	Sahitya Tummala <stummala@codeaurora.org>,
	Vijay Viswanath <vviswana@codeaurora.org>
Subject: Re: [v2] mmc: sdhci-msm: Optionally wait for signal level changes
Date: Tue, 21 Nov 2017 20:38:31 +0100
Message-ID: <2689768.7AuDOzprkX@g550jk> (raw)
In-Reply-To: <20171120195647.22677-1-bjorn.andersson@linaro.org>

On Montag, 20. November 2017 20:56:47 CET 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_SIGNALING_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>
Tested-by: Luca Weiss <luca@z3ntu.xyz>
> ---
> 
> The offending patch is part of your v4.15 pull request, so please pick
> this up for the -rcs.
> 
> Changes since v1:
> - Fixed spelling of swichable...
> 
>  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..c283291db705 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 SWITCHABLE_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 SWITCHABLE_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 & SWITCHABLE_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

  reply index

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-11-20 18:34 [PATCH] " Bjorn Andersson
2017-11-20 19:25 ` Stephen Boyd
2017-11-20 19:56 ` [PATCH v2] " Bjorn Andersson
2017-11-21 19:38   ` Luca Weiss [this message]
2017-11-23 18:13   ` Ulf Hansson

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=2689768.7AuDOzprkX@g550jk \
    --to=luca@z3ntu.xyz \
    --cc=adrian.hunter@intel.com \
    --cc=bjorn.andersson@linaro.org \
    --cc=linux-arm-msm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mmc@vger.kernel.org \
    --cc=sboyd@codeaurora.org \
    --cc=stummala@codeaurora.org \
    --cc=ulf.hansson@linaro.org \
    --cc=vviswana@codeaurora.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

LKML Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/lkml/0 lkml/git/0.git
	git clone --mirror https://lore.kernel.org/lkml/1 lkml/git/1.git
	git clone --mirror https://lore.kernel.org/lkml/2 lkml/git/2.git
	git clone --mirror https://lore.kernel.org/lkml/3 lkml/git/3.git
	git clone --mirror https://lore.kernel.org/lkml/4 lkml/git/4.git
	git clone --mirror https://lore.kernel.org/lkml/5 lkml/git/5.git
	git clone --mirror https://lore.kernel.org/lkml/6 lkml/git/6.git
	git clone --mirror https://lore.kernel.org/lkml/7 lkml/git/7.git
	git clone --mirror https://lore.kernel.org/lkml/8 lkml/git/8.git
	git clone --mirror https://lore.kernel.org/lkml/9 lkml/git/9.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 lkml lkml/ https://lore.kernel.org/lkml \
		linux-kernel@vger.kernel.org
	public-inbox-index lkml

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-kernel


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git