linux-kernel - Re: [PATCH] mmc: Add quirk to disable DDR50 tuning

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <c6093207-2b68-4e3a-8a70-7ab4541ac59f@intel.com>
Date: Tue, 25 Mar 2025 08:33:49 +0200
From: Adrian Hunter <adrian.hunter@...el.com>
To: Erick Shepherd <erick.shepherd@...com>, <ulf.hansson@...aro.org>
CC: <andy-ld.lu@...iatek.com>, <avri.altman@....com>, <dsimic@...jaro.org>,
	<jason.lai@...esyslogic.com.tw>, <jeff.johnson@....qualcomm.com>,
	<jonathan@...pberrypi.com>, <keita.aihara@...y.com>,
	<linux-kernel@...r.kernel.org>, <linux-mmc@...r.kernel.org>,
	<victor.shih@...esyslogic.com.tw>, <wsa+renesas@...g-engineering.com>
Subject: Re: [PATCH] mmc: Add quirk to disable DDR50 tuning

On 24/03/25 21:21, Erick Shepherd wrote:
>> Please move this to mmc_sd_init_uhs_card() instead. Moreover, please
>> add a helper in drivers/mmc/core/card.h for
>> MMC_QUIRK_NO_UHS_DDR50_TUNING, similar to other quirks.
> 
> Sorry for the late response, how does this look? I can change the
> MMC_QUIRK_NO_UHS_DDR50_TUNING check to be before the tuning
> if-statement instead of within it if that seems more appropriate.
> 
> --- a/drivers/mmc/core/card.h
> +++ b/drivers/mmc/core/card.h
> @@ -89,6 +89,7 @@ struct mmc_fixup {
>  #define CID_MANFID_MICRON       0x13
>  #define CID_MANFID_SAMSUNG      0x15
>  #define CID_MANFID_APACER       0x27
> +#define CID_MANFID_SWISSBIT     0x5D
>  #define CID_MANFID_KINGSTON     0x70
>  #define CID_MANFID_HYNIX	0x90
>  #define CID_MANFID_KINGSTON_SD	0x9F
> @@ -294,4 +295,9 @@ static inline int mmc_card_broken_sd_poweroff_notify(const struct mmc_card *c)
>  	return c->quirks & MMC_QUIRK_BROKEN_SD_POWEROFF_NOTIFY;
>  }
>  
> +static inline int mmc_card_no_uhs_ddr50_tuning(const struct mmc_card *c)
> +{
> +	return c->quirks & MMC_QUIRK_NO_UHS_DDR50_TUNING;
> +}
> +
> 
> --- a/drivers/mmc/core/sd.c
> +++ b/drivers/mmc/core/sd.c
> @@ -664,6 +664,10 @@ static int mmc_sd_init_uhs_card(struct mmc_card *card)
> 	if (!mmc_host_is_spi(card->host) &&
>  		(card->host->ios.timing == MMC_TIMING_UHS_SDR50 ||
>  		 card->host->ios.timing == MMC_TIMING_UHS_DDR50 ||
>  		 card->host->ios.timing == MMC_TIMING_UHS_SDR104)) {
> +		if ((card->quirks & MMC_QUIRK_NO_UHS_DDR50_TUNING) &&
> +		    card->host->ios.timing == MMC_TIMING_UHS_DDR50)
> +			goto out;

Perhaps make a helper function (untested):


static bool mmc_sd_use_tuning(struct mmc_card *card)
{
	if (mmc_host_is_spi(card->host))
		return false;

	switch (card->host->ios.timing) {
	case MMC_TIMING_UHS_SDR50:
	case MMC_TIMING_UHS_SDR104:
		return true;
	case MMC_TIMING_UHS_DDR50:
		return !mmc_card_no_uhs_ddr50_tuning(card);
	}

	return false;
}

Then change to:

	if (mmc_sd_use_tuning(card)) {
		err = mmc_execute_tuning(card);
		etc
	}


> +
>  		err = mmc_execute_tuning(card);
>  
>  		/*
> 
> Regards,
> Erick