[PATCH 0/2] mmc: speed up secure erase on ISSI IS22TF128G eMMC

[Michael Haener <michael.haener@siemens.com>]

Secure erasing a 33.5GiB partition on an ISSI IS22TF128G eMMC (NXP
i.MX8, sdhci-esdhc-imx) takes 5-7 hours, because the request is split
into roughly 10000 max_discard sized secure erase commands, each with a
large fixed overhead.

Patch 1 adds the card to MMC_QUIRK_FIXED_SECURE_ERASE_TRIM_TIME, which
brings the same operation down to about 6 minutes. It is tagged for
stable.

Patch 2 is hardening for the quirk: with qty no longer bound by
max_busy_timeout, the 32-bit erase timeout calculation can overflow for
cards with large ERASE_TIMEOUT_MULT * SEC_ERASE_MULT. None of the
currently quirked cards reach that limit (the ISSI card is at about
half of it), so it is not tagged for stable.

Michael Haener (2):
  mmc: add ISSI IS22TF128G to fixed secure erase time quirk
  mmc: core: saturate erase timeout instead of overflowing

 drivers/mmc/core/card.h   |  1 +
 drivers/mmc/core/core.c   | 19 ++++++++++++++-----
 drivers/mmc/core/quirks.h |  9 +++++++++
 3 files changed, 24 insertions(+), 5 deletions(-)

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2.56.0