BUG_ONs doesn't help anything except for stop the system from
running. If it occurs, it implies we should deploy proper error
handling for that. So this patch is gonna discard these meaningless
BUG_ONs and deploy error handling if needed.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

BUG_ONs doesn't help anything except for stop the system from
running. If it occurs, it implies we should deploy proper error
handling for that. So this patch is gonna discard these meaningless
BUG_ONs and deploy error handling if needed.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Return error value for file_operations callback instead
of triggering BUG_ON which is meaningless. Personally I
don't believe n != EXT_CSD_STR_LEN could happen. Anyway,
propagate the error to the caller.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

BUG_ONs doesn't help anything except for stop the system from
running. If it occurs, it implies we should deploy proper error
handling for that. So this patch is gonna discard these meaningless
BUG_ONs and deploy error handling if needed.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Add definitions relating to Command Queuing.
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>

Add a mmc_queue member to record the size of the queue, which currently
supports 2 requests on-the-go at a time. Instead of allocating resources
for 2 slots in the queue, allow for an arbitrary number.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

In preparation for supporting a queue of requests, factor out
mmc_queue_reqs_free_bufs().
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Harjani Ritesh <riteshh@codeaurora.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

In preparation for supporting a queue of requests, factor out
mmc_queue_alloc_sgs().
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Harjani Ritesh <riteshh@codeaurora.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

In preparation for supporting a queue of requests, factor out
mmc_queue_alloc_bounce_sgs().
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Harjani Ritesh <riteshh@codeaurora.org>
[Ulf: Fixed compiler warning]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

In preparation for supporting a queue of requests, factor out
mmc_queue_alloc_bounce_bufs().
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Harjani Ritesh <riteshh@codeaurora.org>
[Ulf: Fixed compiler warning]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

The only time the driver sleeps expecting to be woken upon the arrival of
a new request, is when the dispatch queue is empty. The only time that it
is known whether the dispatch queue is empty is after NULL is returned
from blk_fetch_request() while under the queue lock.

Recognizing those facts, simplify the synchronization between the queue
thread and the request function. A couple of flags tell the request
function what to do, and the queue lock and barriers associated with
wake-ups ensure synchronization.

The result is simpler and allows the removal of the context_info lock.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Harjani Ritesh <riteshh@codeaurora.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

The 4K native sector check does not allow for the 'do' loop nor the
variables used after the 'cmd_abort' label.

'brq' and 'req' get reassigned in the 'do' loop, so the check must not
assume what their values are. After the 'cmd_abort' label, 'mq_rq' and
'req' are used, but 'rqc' must be NULL otherwise it can be started again.
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>

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

We get the following warning with the driver is compiled in:

WARNING: modpost: Found 1 section mismatch(es).
To see full details build your kernel with:
'make CONFIG_DEBUG_SECTION_MISMATCH=y'

With CONFIG_DEBUG_SECTION_MISMATCH enabled, the details are reported:

WARNING: vmlinux.o(.text+0x55d014): Section mismatch in reference from the
function fsl_guts_probe() to the function
.init.text:of_flat_dt_get_machine_name()
The function fsl_guts_probe() references
the function __init of_flat_dt_get_machine_name().
This is often because fsl_guts_probe lacks a __init
annotation or the annotation of of_flat_dt_get_machine_name is wrong.

This patch fixes the issue by using the normal DT/OF API rather than
the of_flat_* one.

Cc: Scott Wood <oss@buserror.net>
Cc: Yangbo Lu <yangbo.lu@nxp.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

The eSDHC of T4240-R1.0-R2.0 has incorrect vender version and spec version.
Acturally the right version numbers should be VVN=0x13 and SVN = 0x1.
This patch adds the GUTS driver support for eSDHC driver to match SoC.
And fix host version to avoid that incorrect version numbers break down
the ADMA data transfer.
Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Scott Wood <oss@buserror.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Add maintainer entry for Freescale SoC drivers including
the QE library and the GUTS driver now. Also add maintainer
for QE library.
Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Acked-by: Scott Wood <oss@buserror.net>
Acked-by: Qiang Zhao <qiang.zhao@nxp.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

The global utilities block controls power management, I/O device
enabling, power-onreset(POR) configuration monitoring, alternate
function selection for multiplexed signals,and clock control.

This patch adds a driver to manage and access global utilities block.
Initially only reading SVR and registering soc device are supported.
Other guts accesses, such as reading RCW, should eventually be moved
into this driver as well.
Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Move guts devicetree doc to Documentation/devicetree/bindings/soc/fsl/
since it's used by not only PowerPC but also ARM. And add a specification
for 'little-endian' property.
Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Scott Wood <oss@buserror.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Add the dts node for device configuration unit that provides
general purpose configuration and status for the device.
Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Acked-by: Scott Wood <oss@buserror.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Merge the immutable soc-device-match-tag1 provided by Geert Uytterhoeven
to pull in the new soc_device_match() interface for matching against
soc_bus attributes.

Simply document new compatibility strings as the driver is already
activated using a fallback compatibility string.

These compat strings are in keeping with those for all other
Renesas ARM based SoCs with sh_mmcif enabled in mainline.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Remove documentation of support for the SH7372 (SH-Mobile AP4) from the MMC
driver. The driver itself appears to have no SH7372 specific code.

Commit edf41009 ("ARM: shmobile: sh7372 dtsi: Remove Legacy file")
removes this SoC from the kernel in v4.1.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

I've had it with this code now.

The packed command support is a complex hurdle in the MMC/SD block
layer, around 500+ lines of code which was introduced in 2013 in

commit ce39f9d1 ("mmc: support packed write command for eMMC4.5
devices")
commit abd9ac14 ("mmc: add packed command feature of eMMC4.5")

...and since then it has been rotting. The original author of the
code has disappeared from the community and the mail address is
bouncing.

For the code to be exercised the host must flag that it supports
packed commands, so in mmc_blk_prep_packed_list() which is called for
every single request, the following construction appears:

u8 max_packed_rw = 0;

if ((rq_data_dir(cur) == WRITE) &&
    mmc_host_packed_wr(card->host))
        max_packed_rw = card->ext_csd.max_packed_writes;

if (max_packed_rw == 0)
    goto no_packed;

This has the following logical deductions:

- Only WRITE commands can really be packed, so the solution is
  only half-done: we support packed WRITE but not packed READ.
  The packed command support has not been finalized by supporting
  reads in three years!

- mmc_host_packed_wr() is just a static inline that checks
  host->caps2 & MMC_CAP2_PACKED_WR. The problem with this is
  that NO upstream host sets this capability flag! No driver
  in the kernel is using it, and we can't test it. Packed
  command may be supported in out-of-tree code, but I doubt
  it. I doubt that the code is even working anymore due to
  other refactorings in the MMC block layer, who would
  notice if patches affecting it broke packed commands?
  No one.

- There is no Device Tree binding or code to mark a host as
  supporting packed read or write commands, just this flag
  in caps2, so for sure there are not any DT systems using
  it either.

It has other problems as well: mmc_blk_prep_packed_list() is
speculatively picking requests out of the request queue with
blk_fetch_request() making the MMC/SD stack harder to convert
to the multiqueue block layer. By this we get rid of an
obstacle.

The way I see it this is just cruft littering the MMC/SD
stack.

Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Maya Erez <qca_merez@qca.qualcomm.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

The void (*pre_req) callback in the struct mmc_host_ops vtable
is passing an argument "is_first_req" indicating whether this is
the first request or not.

None of the in-kernel users use this parameter: instead, since
they all just do variants of dma_map* they use the DMA cookie
to indicate whether a pre* callback has already been done for
a request when they decide how to handle it.

Delete the parameter from the callback and all users, as it is
just pointless cruft.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

According to the JEDEC specification, during bus timing change operations
for mmc, sending a CMD13 could trigger CRC errors.

As switching to HS DDR mode indeed causes a bus timing change, polling with
CMD13 to detect card busy, may thus potentially trigger CRC errors.
Currently these errors are treated as the switch to HS DDR mode failed.

To improve this behaviour, let's instead tell __mmc_switch() to retry when
it encounters CRC errors during polling.

Moreover, when switching to HS DDR mode, let's make sure the CMD13 polling
is done by having the mmc host and the mmc card, being configured to
operate at the same selected bus speed timing. Fix this by providing
MMC_TIMING_MMC_DDR52 as the timing parameter to __mmc_switch().
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>

In cases when the mmc host doesn't support HW busy detection, polling for a
card being busy by using CMD13 is beneficial. That is because, instead of
waiting a fixed amount of time, 500ms or the generic CMD6 time from
EXT_CSD, we find out a lot sooner when the card stops signaling busy. This
leads to a significant decreased total initialization time for the mmc
card.

However, to allow polling with CMD13 during a bus timing change operation,
such as switching to HS mode, we first need to update the mmc host's bus
timing before starting to poll. Deal with that, simply by providing
MMC_TIMING_MMC_HS as the timing parameter to __mmc_switch() from
mmc_select_hs().

By telling __mmc_switch() to allow polling with CMD13, also makes it
validate the CMD6 status, thus we can remove the corresponding checks.

When switching to HS400ES, the mmc_select_hs() function is called in one of
the intermediate steps. To still prevent CMD13 polling for HS400ES, let's
call the __mmc_switch() function in this path as it enables us to keep
using the existing method.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>

In cases when a speed mode change is requested for mmc cards, a CMD6 is
sent by calling __mmc_switch() during the card initialization. The CMD6
leads to the card entering a busy period. When that is completed, the host
must parse the CMD6 status to find out whether the change of the speed mode
succeeded.

To enable the mmc core to poll the card by using CMD13 to find out when the
busy period is completed, it's reasonable to make sure polling is done by
having the mmc host and the mmc card, being configured to operate at the
same selected bus speed timing.

Therefore, let's extend __mmc_switch() to take yet another parameter, which
allow its callers to update the bus speed timing of the mmc host. In this
way, __mmc_switch() also becomes capable of reading and validating the CMD6
status by sending a CMD13, in cases when that's desired.

If __mmc_switch() encounters a failure, we make sure to restores the old
bus speed timing for the mmc host, before propagating the error code.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>

According to the JEDEC specification, the SWITCH_ERROR bit in the device
status from a R1 response, is an error bit which may be cleared as soon as
the response that reports the error is sent.

When polling with CMD13 to find out when the card stops signaling busy
after a CMD6 has been sent, we currently parse only the last CMD13 response
for the SWITCH_ERROR bit. Consequentially we could loose important
information about the card.

In worst case if the card stops signaling busy within the allowed timeout,
we could end up believing that the CMD6 command completed successfully,
when in fact it didn't.

To improve the behaviour, let's parse each CMD13 response to see if the
SWITCH_ERROR bit is set in the device status. In such case, we abort the
polling loop and report the error.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>

The ignore_crc parameter/variable name is used at a couple of places in the
mmc core. Let's rename it to retry_crc_err to reflect its new purpose.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>

There are only one users left which calls __mmc_send_status(). Moreover,
the ignore_crc parameter isn't being used, so let's just remove these
redundant parts.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>

After a CMD6 command has been sent, the __mmc_switch() function might be
advised to poll the card for busy by using CMD13 and also by ignoring CRC
errors.

In the case of ignoring CRC errors, the mmc core tells the mmc host to also
ignore these errors via masking the MMC_RSP_CRC response flag. This seems
wrong, as it leads to that the mmc host could propagate an unreliable
response, instead of a proper error code.

What we really want, is not to ignore CRC errors but instead retry the
polling attempt. So, let's change this by treating a CRC error as the card
is still being busy and thus continue to run the polling loop.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>

With commit f35bbf61 ("gpio / ACPI: Return -EPROBE_DEFER if the
gpiochip was not found"), a gpio descriptor request can now be deferred if
the providing gpio host controller driver hasn't been loaded yet. Allow use
in mmc slot probe in order to prevent card detect gpio setup from failing
in this case.
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Add support for eMMC/SD/SDIO Intel GLK host controllers.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

The newer msm sdhci's cores use a different DLL hardware for HS400.
Update the configuration and calibration of the newer DLL block.

The HS400 DLL block used previously is CDC LP 533 and requires
programming multiple registers and waiting for configuration to
complete and then enable it. It has about 18 register writes and
two register reads.

The newer HS400 DLL block is SDC4 DLL and requires two register
writes for configuration and one register read to confirm that it
is initialized. There is an additional register write to enable
the power save mode for SDC4 DLL block.
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Signed-off-by: Krishna Konda <kkonda@codeaurora.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

In HS400 mode a new RCLK is introduced on the interface for read data
transfers. The eMMC5.0 device transmits the read data to the host with
respect to rising and falling edges of RCLK. In order to ensure correct
operation of read data transfers in HS400 mode, the incoming RX data
needs to be sampled by delayed version of RCLK.

The CDCLP533 delay circuit shifts the RCLK by T/4. It needs to be
initialized, configured and enabled once during HS400 mode switch and
when operational voltage/clock is changed.
Signed-off-by: Venkat Gopalakrishnan <venkatg@codeaurora.org>
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Save the tuning phase once the tuning is performed.
This phase value will be used while calibrating DLL
for HS400 mode.
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

The following msm platform specific changes are added to support HS400.
- Allow tuning for HS400 mode.
- Configure HS400 timing mode using the VENDOR_SPECIFIC_FUNC register.
Signed-off-by: Venkat Gopalakrishnan <venkatg@codeaurora.org>
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

SDHC MSM controller need 2x clock for MCLK at GCC.
Hence make required changes to have 2x clock for
DDR timing modes.
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

sdhci-msm controller may have different clk-rates for each
bus speed mode. Thus implement set_clock callback for
sdhci-msm driver.
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Factor out sdhci_enable_clk from sdhci_set_clock
and make it EXPORT_SYMBOL so that it can be called.
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>