Commit Graph

19 Commits

Author SHA1 Message Date
Wolfram Sang
8ffb2611a7 mmc: host: factor out clearing the retune state
We have this in two places, so let's have a dedicated function. It is
also more readable.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20210624151616.38770-4-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2021-08-24 10:15:28 +02:00
Ulf Hansson
ead49373d2 mmc: core: Initial support for SD express card/host
In the SD specification v7.10 the SD express card has been added. This new
type of removable SD card, can be managed via a PCIe/NVMe based interface,
while also allowing backwards compatibility towards the legacy SD
interface.

To keep the backwards compatibility, it's required to start the
initialization through the legacy SD interface. If it turns out that the
mmc host and the SD card, both supports the PCIe/NVMe interface, then a
switch should be allowed.

Therefore, let's introduce some basic support for this type of SD cards to
the mmc core. The mmc host, should set MMC_CAP2_SD_EXP if it supports this
interface and MMC_CAP2_SD_EXP_1_2V, if also 1.2V is supported, as to inform
the core about it.

To deal with the switch to the PCIe/NVMe interface, the mmc host is
required to implement a new host ops, ->init_sd_express(). Based on the
initial communication between the host and the card, host->ios.timing is
set to either MMC_TIMING_SD_EXP or MMC_TIMING_SD_EXP_1_2V, depending on if
1.2V is supported or not. In this way, the mmc host can check these values
in its ->init_sd_express() ops, to know how to proceed with the handover.

Note that, to manage card insert/removal, the mmc core sticks with using
the ->get_cd() callback, which means it's the host's responsibility to make
sure it provides valid data, even if the card may be managed by PCIe/NVMe
at the moment. As long as the card seems to be present, the mmc core keeps
the card powered on.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Rui Feng <rui_feng@realsil.com.cn>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/1603936636-3126-1-git-send-email-rui_feng@realsil.com.cn
2020-11-16 11:59:28 +01:00
Thomas Gleixner
d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
Shawn Lin
d6743a8a1a mmc: core: Don't try UHS-I mode if 4-bit mode isn't supported
Per SD specification physical layer v4.0, section 3.9.4, it
says "UHS-I supports only 4-bit mode. Host shall select 4-bit
mode by ACMD6. However mmc_sd_init_uhs_card() still go ahead
to initialize the cards anyway, whether card or host won't
support 4-bit mode.

  This breaks the platforms which could support UHS-I mode but on
some certain boards only support 1-bit mode with a UHS-I card inserted,
as all the tuning process is broken due to this. Alternatively, we
should check the return value from mmc_set_bus_width() to see if host
could finish the request to switch the bus width on its side. But that
needs more thing to do than this patch that just bails out early to try
high speed mode if 4-bit mode isn't available for whatever reason. And
this patch could also fix the same problem for sdio since R4_18V_PRESENT
won't be set for ocr when mmc_sdio_init_card() finds mmc_host_uhs()
is false.

  Note that this patch doesn't keep the checking of card->scr.sda_spec3
and comparing card->scr.bus_widths with SD_SCR_BUS_WIDTH_4 within
mmc_sd_init_uhs_card() since if the sd cards response with SD_ROCR_S18A,
it definitely supports UHS-I mode, which implicitly means these checkings
are always true.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2018-03-15 09:30:39 +01:00
Adrian Hunter
126b627003 mmc: core: Remove code no longer needed after the switch to blk-mq
Remove code no longer needed after the switch to blk-mq.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-12-11 13:05:58 +01:00
Adrian Hunter
1bec43a3b1 mmc: core: Remove option not to use blk-mq
Remove config option MMC_MQ_DEFAULT and parameter mmc_use_blk_mq, so that
blk-mq must be used always.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-12-11 12:55:02 +01:00
Adrian Hunter
10f21df4a2 mmc: block: blk-mq: Add support for direct completion
For blk-mq, add support for completing requests directly in the ->done
callback. That means that error handling and urgent background operations
must be handled by recovery_work in that case.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
2017-12-11 12:44:35 +01:00
Adrian Hunter
c3d53d0da6 mmc: core: Add parameter use_blk_mq
Until mmc has blk-mq support fully implemented and tested, add a parameter
use_blk_mq, set to true if config option MMC_MQ_DEFAULT is selected, which
it is by default.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
2017-12-11 12:44:33 +01:00
Adrian Hunter
cb39f61e9b mmc: core: Export a few functions needed for blkmq support
The following functions are needed by the mmc block device driver, once it
converts to blkmq, therefore let's export them.

mmc_start_bkops()
mmc_start_request()
mmc_retune_hold_now()
mmc_retune_release()

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-10-30 11:45:56 +01:00
Adrian Hunter
bf517d6fec mmc: core: Add mmc_retune_hold_now()
mmc_return_hold() / mmc_retune_release() are used around a group of
commands to prevent re-tuning between the commands. Re-tuning can still
happen before the first command. In some cases, re-tuning must be
prevented entirely. Add mmc_retune_hold_now() for that purpose. It is
added in preparation for CQE support where it will be used by CQE recovery.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-08-30 14:02:01 +02:00
Ulf Hansson
5857b29b96 mmc: core: Move public functions from host.h to private headers
A significant amount of functions are available through the public mmc
host.h header file. Let's slim down this public mmc interface, as to
prevent users from abusing it, by moving some of the functions to private
mmc host.h header file.

This change concentrates on moving the functions into private mmc headers,
following changes may continue with additional clean-ups.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
2017-02-13 13:20:25 +01:00
Ulf Hansson
066185d690 mmc: core: First step in cleaning up private mmc header files
This is the first step in cleaning up the private mmc header files. In this
change we makes sure each header file builds standalone, as that helps to
resolve dependencies.

While changing this, it also seems reasonable to stop including other
headers from inside a header itself which it don't depend upon.
Additionally, in some cases such dependencies are better resolved by
forward declaring the needed struct.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
2017-02-13 13:20:20 +01:00
Adrian Hunter
dfa13ebbe3 mmc: host: Add facility to support re-tuning
Currently, there is core support for tuning during
initialization. There can also be a need to re-tune
periodically (e.g. sdhci) or to re-tune after the
host controller is powered off (e.g. after PM
runtime suspend / resume) or to re-tune in response
to CRC errors.

The main requirements for re-tuning are:
  - ability to enable / disable re-tuning
  - ability to flag that re-tuning is needed
  - ability to re-tune before any request
  - ability to hold off re-tuning if the card is busy
  - ability to hold off re-tuning if re-tuning is in
  progress
  - ability to run a re-tuning timer

To support those requirements 7 members are added to struct
mmc_host:

  unsigned int		can_retune:1;	/* re-tuning can be used */
  unsigned int		doing_retune:1;	/* re-tuning in progress */
  unsigned int		retune_now:1;   /* do re-tuning at next req */
  int			need_retune;	/* re-tuning is needed */
  int			hold_retune;	/* hold off re-tuning */
  unsigned int		retune_period;  /* re-tuning period in secs */
  struct timer_list	retune_timer;	/* for periodic re-tuning */

need_retune is an integer so it can be set without needing
synchronization. hold_retune is a integer to allow nesting.

Various simple functions are provided to set / clear those
variables.

Subsequent patches take those functions into use.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:06:53 +02:00
Adrian Hunter
907d2e7cc7 mmc: start removing enable / disable API
Most parts of the enable / disable API are no longer used and
can be removed.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Venkatraman S <svenkatr@ti.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
2012-03-27 12:20:03 -04:00
Sujit Reddy Thumma
2c4967f741 mmc: core: Ensure clocks are always enabled before host interaction
Ensure clocks are always enabled before any interaction with the
host controller driver. This makes sure that there is no race
between host execution and the core layer turning off clocks
in different context with clock gating framework.

Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Per Forlin <per.forlin@stericsson.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
2012-02-13 20:38:58 -05:00
Mika Westerberg
08c14071fd mmc: rename mmc_host_clk_{ungate|gate} to mmc_host_clk_{hold|release}
As per suggestion by Linus Walleij:

  > If you think the names of the functions are confusing then
  > you may rename them, say like this:
  >
  > mmc_host_clk_ungate() -> mmc_host_clk_hold()
  > mmc_host_clk_gate() -> mmc_host_clk_release()
  >
  > Which would make the usecases more clear

(This is CC'd to stable@ because the next two patches, which fix
observable races, depend on it.)

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: <stable@kernel.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-08-31 16:24:54 -04:00
Linus Walleij
04566831a7 mmc: Aggressive clock gating framework
This patch modifies the MMC core code to optionally call the set_ios()
operation on the driver with the clock frequency set to 0 (gate) after
a grace period of at least 8 MCLK cycles, then restore it (ungate)
before any new request. This gives the driver the option to shut down
the MCI clock to the MMC/SD card when the clock frequency is 0, i.e.
the core has stated that the MCI clock does not need to be generated.

It is inspired by existing clock gating code found in the OMAP and
Atmel drivers and brings this up to the host abstraction.  Gating is
performed before and after any MMC request.

This patchset implements this for the MMCI/PL180 MMC/SD host controller,
but it should be simple to switch OMAP/Atmel over to using this instead.

mmc_set_{gated,ungated}() add variable protection to the state holders
for the clock gating code.  This is particularly important when ordinary
.set_ios() calls would race with the .set_ios() call resulting from a
delayed gate operation.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Reviewed-by: Chris Ball <cjb@laptop.org>
Tested-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-01-08 22:48:03 -05:00
Adrian Hunter
8ea926b22e mmc: add 'enable' and 'disable' methods to mmc host
MMC hosts that support power saving can use the 'enable' and 'disable'
methods to exit and enter power saving states.  An explanation of their
use is provided in the comments added to include/linux/mmc/host.h.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Matt Fleming <matt@console-pimps.org>
Cc: Ian Molton <ian@mnementh.co.uk>
Cc: "Roberto A. Foglietta" <roberto.foglietta@gmail.com>
Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Cc: Denis Karpov <ext-denis.2.karpov@nokia.com>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Philip Langdale <philipl@overt.org>
Cc: "Madhusudhan" <madhu.cr@ti.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-23 07:39:33 -07:00
Pierre Ossman
b93931a61a mmc: refactor host class handling
Move basic host class device handling to its own file for clarity.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2007-07-09 21:28:01 +02:00