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This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The mmc_read_ssr() function results in DMA to the raw_ssr member of
struct mmc_card, which is not guaranteed to be cache line aligned & thus
might not meet the requirements set out in Documentation/DMA-API.txt:
Warnings: Memory coherency operates at a granularity called the cache
line width. In order for memory mapped by this API to operate
correctly, the mapped region must begin exactly on a cache line
boundary and end exactly on one (to prevent two separately mapped
regions from sharing a single cache line). Since the cache line size
may not be known at compile time, the API will not enforce this
requirement. Therefore, it is recommended that driver writers who
don't take special care to determine the cache line size at run time
only map virtual regions that begin and end on page boundaries (which
are guaranteed also to be cache line boundaries).
On some systems where DMA is non-coherent this can lead to us losing
data that shares cache lines with the raw_ssr array.
Fix this by kmalloc'ing a temporary buffer to perform DMA into. kmalloc
will ensure the buffer is suitably aligned, allowing the DMA to be
performed without any loss of data.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: 5275a652d296 ("mmc: sd: Export SD Status via “ssr” device attribute")
Cc: <stable@vger.kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Commit e0097cf5f2f1 ("mmc: queue: Fix queue thread wake-up") did not go far
enough. mmc_wait_for_data_req_done() still contains some problems and can
be further simplified. First it should not touch
context_info->is_waiting_last_req because that is a wake-up control used by
the owner of the context. Secondly, it should always return when one of its
wake-up conditions is met because, again, that is contolled by the owner of
the context.
While the current block driver does not have an issue, these problems were
exposed during testing of the Software Command Queue patches.
Fixes: e0097cf5f2f1 ("mmc: queue: Fix queue thread wake-up")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Harjani Ritesh <riteshh@codeaurora.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Since commit c2c24819b280 ("mmc: core: Don't power off the card when
starting the host"), the power state can still be MMC_POWER_UNDEFINED after
mmc_start_host() is called. That can trigger a warning in SDHCI during
runtime resume as it tries to restore the I/O state. Handle
MMC_POWER_UNDEFINED simply by not updating the I/O state in that case.
Fixes: c2c24819b280 ("mmc: core: Don't power off the card when starting the host")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Add a Socionext SoC specific compatible (suggested by Rob Herring).
No SoC specific data are associated with the compatible strings for
now, but other SoC vendors may use this IP and want to differentiate
IP variants in the future.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc
Pull another MMC update from Ulf Hansson:
"Here's a second pull request for MMC for v4.10.
As a matter of fact it's only one change that moves some mmc files
around. I thought it was a good idea to get this into v4.10, as it
gives us a nice and fresh base for v4.11. Summary:
MMC core:
- Move files from the card directory to the core directory to enable
future clean-ups of the generic mmc header files and interfaces"
* tag 'mmc-v4.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
mmc: block: Move files to core
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Pull block layer updates from Jens Axboe:
"This is the main block pull request this series. Contrary to previous
release, I've kept the core and driver changes in the same branch. We
always ended up having dependencies between the two for obvious
reasons, so makes more sense to keep them together. That said, I'll
probably try and keep more topical branches going forward, especially
for cycles that end up being as busy as this one.
The major parts of this pull request is:
- Improved support for O_DIRECT on block devices, with a small
private implementation instead of using the pig that is
fs/direct-io.c. From Christoph.
- Request completion tracking in a scalable fashion. This is utilized
by two components in this pull, the new hybrid polling and the
writeback queue throttling code.
- Improved support for polling with O_DIRECT, adding a hybrid mode
that combines pure polling with an initial sleep. From me.
- Support for automatic throttling of writeback queues on the block
side. This uses feedback from the device completion latencies to
scale the queue on the block side up or down. From me.
- Support from SMR drives in the block layer and for SD. From Hannes
and Shaun.
- Multi-connection support for nbd. From Josef.
- Cleanup of request and bio flags, so we have a clear split between
which are bio (or rq) private, and which ones are shared. From
Christoph.
- A set of patches from Bart, that improve how we handle queue
stopping and starting in blk-mq.
- Support for WRITE_ZEROES from Chaitanya.
- Lightnvm updates from Javier/Matias.
- Supoort for FC for the nvme-over-fabrics code. From James Smart.
- A bunch of fixes from a whole slew of people, too many to name
here"
* 'for-4.10/block' of git://git.kernel.dk/linux-block: (182 commits)
blk-stat: fix a few cases of missing batch flushing
blk-flush: run the queue when inserting blk-mq flush
elevator: make the rqhash helpers exported
blk-mq: abstract out blk_mq_dispatch_rq_list() helper
blk-mq: add blk_mq_start_stopped_hw_queue()
block: improve handling of the magic discard payload
blk-wbt: don't throttle discard or write zeroes
nbd: use dev_err_ratelimited in io path
nbd: reset the setup task for NBD_CLEAR_SOCK
nvme-fabrics: Add FC LLDD loopback driver to test FC-NVME
nvme-fabrics: Add target support for FC transport
nvme-fabrics: Add host support for FC transport
nvme-fabrics: Add FC transport LLDD api definitions
nvme-fabrics: Add FC transport FC-NVME definitions
nvme-fabrics: Add FC transport error codes to nvme.h
Add type 0x28 NVME type code to scsi fc headers
nvme-fabrics: patch target code in prep for FC transport support
nvme-fabrics: set sqe.command_id in core not transports
parser: add u64 number parser
nvme-rdma: align to generic ib_event logging helper
...
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Once upon a time it made sense to keep the mmc block device driver and its
related code, in its own directory called card. Over time, more an more
functions/structures have become shared through generic mmc header files,
between the core and the card directory. In other words, the relationship
between them has become closer.
By sharing functions/structures via generic header files, it becomes easy
for outside users to abuse them. In a way to avoid that from happen, let's
move the files from card directory into the core directory, as it enables
us to move definitions of functions/structures into mmc core specific
header files.
Note, this is only the first step in providing a cleaner mmc interface for
outside users. Following changes will do the actual cleanup, as that is not
part of this change.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
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Add a driver for the Cadence SD4HC SD/SDIO/eMMC Controller.
For SD, it basically relies on the SDHCI standard code.
For eMMC, this driver provides some callbacks to support the
hardware part that is specific to this IP design.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Some SDHCI-compat controllers support not only SD, but also eMMC,
but they use different commands for tuning: CMD19 for SD, CMD21 for
eMMC.
Due to the difference of the underlying mechanism, some controllers
(at least, the Cadence IP is the case) provide their own registers
for the eMMC tuning.
This commit will be useful when we want to override .execute_tuning
callback (for eMMC HS200 tuning), but still let it fall back to
sdhci_execute_tuning() for SD timing.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Tidy the tuning loop by moving it to a separate function and making it a
for-loop.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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There are only 2 possible block sizes, so simplify 2 if-statements into 1.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Factor out some functions to tidy up the code in sdhci_execute_tuning.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Use mmc_abort_tuning() instead of open-coding the stop command.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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If a tuning command times out, the card could still be processing it, which
will cause problems for recovery. The eMMC specification says that CMD12
can be used to stop CMD21, so add a function that does that.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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SDHCI falls back to fixed sampling if there is an error during tuning.
However it also reports an error unless there is periodic re-tuning.
That is not the best option because:
a) there is a reasonable chance that fixed sampling will work, especially
at room temperature.
b) re-tuning will be done again anyway if there are CRC errors.
Change to return no error always when falling back to fixed sampling.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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If the driver has exhausted the maximum number of tuning loops, then fixed
sampling is used. To do that both SDHCI_CTRL_TUNED_CLK and
SDHCI_CTRL_EXEC_TUNING must be reset to 0, but only SDHCI_CTRL_TUNED_CLK
was being reset. Reset SDHCI_CTRL_EXEC_TUNING to 0 also.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Clearing the tuning bits should reset the tuning circuit. However there is
more to do. Reset the command and data lines for good measure, and then
for eMMC ensure the card is not still trying to process a tuning command by
sending a stop command.
Note the JEDEC eMMC specification says the stop command (CMD12) can be used
to stop a tuning command (CMD21) whereas the SD specification is silent on
the subject with respect to the SD tuning command (CMD19). Considering that
CMD12 is not a valid SDIO command, the stop command is sent only when the
tuning command is CMD21 i.e. for eMMC. That addresses cases seen so far
which have been on eMMC.
Note that this replaces the commit fe5fb2e3b58f ("mmc: sdhci: Reset cmd and
data circuits after tuning failure") which is being reverted for v4.9+.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Dan O'Donovan <dan@emutex.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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This reverts commit fe5fb2e3b58f ("mmc: sdhci: Reset cmd and data circuits
after tuning failure").
A better fix is available, and it will be applied to older stable releases,
so get this out of the way by reverting it.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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The JEDEC specification indicates CMD13 can be used after a HS200 switch
to check for errors. However in practice some boards experience CRC errors
in the CMD13 response. Consequently, for HS200, CRC errors are not a
reliable way to know the switch failed. If there really is a problem, we
would expect tuning will fail and the result ends up the same. So change
the error condition to ignore CRC errors in that case.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Add an entry for the SDIO bus in the ECS EF20 cherry trail laptop:
Device (SDHB) {
Name (_ADR, 0x00110000)
Name (_HID, "80860F14" /* Intel Baytrail SDIO/MMC Host Controller */)
Name (_CID, "PNP0D40" /* SDA Standard Compliant SD Host Controller */)
Name (_DDN, "Intel(R) SDIO Controller - 80862295")
Name (_UID, 0x02)
Name (_HRV, One)
A SDHB device with the same _HID and _UID can also be found on other
cherry trail products like Chuwi Hi10.
Signed-off-by: Daniel Drake <drake@endlessm.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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I see no override of read/write callbacks in sdhci-of-at91.c.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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On NI 9037 boards the max SDIO frequency is limited by trace lengths
and other layout choices. The max SDIO frequency is stored in an ACPI
table.
The driver reads the ACPI entry MXFQ during sdio_probe_slot and sets the
f_max field of the host.
Signed-off-by: Nathan Sullivan <nathan.sullivan@ni.com>
Reviewed-by: Jaeden Amero <jaeden.amero@ni.com>
Reviewed-by: Josh Cartwright <joshc@ni.com>
Signed-off-by: Zach Brown <zach.brown@ni.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Add PCI ID for Intel byt sdio host controller sub-vended by NI.
The controller has different behavior because of the board layout NI
puts it on.
Signed-off-by: Zach Brown <zach.brown@ni.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Before calling clk_round_rate(), put the spin_unlock_irq() in
sdhci_s3c_consider_clock() function.
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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When card is polling (broken-cd), there is a spamming messge related to
clock.
After applied this patch, display the message only one time at boot
time. It's enough to check which clock values is used.
Also prevent to display the spamming message.
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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If card is polling or non-removable, display the more exact message.
It's helpful to debug which detecting scheme is using.
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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Before checking flags, it has to check "present" variable.
Otherwise, flags should be cleared everytime.
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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The commit 64997de4fd17 ("mmc: dw_mmc: remove system PM callback") is
missing to call dw_mci_ctrl_reset(). This adds to call
dw_mci_ctrl_reset() and to handle error of clocks.
Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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The dw_mmc-exynos should be RPM_ACTIVE on probe() to call suspend
callback of runtime PM in pm_runtime_force_suspend() during first system
suspend. Also call pm_runtime_get_noresume() on probe() because it
doesn't call suspend/resume callback by runtime PM now.
Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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It is unnecessary to panic the kernel when testing mmc. Instead,
cast a warning for folkz to debug and return the error code to
the caller to indicate the failure of this test should be enough.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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bounce_sg for mqrq_cur and mqrq_pre are proper
allocated when initializing the queue and will not
be freed before explicitly cleaning the queue. So from
the code itself it should be quite confident to remove
this check. If that BUG_ON take effects, it is mostly
likely the memory is randomly oopsing.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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The code seems quite simple to maintain the sdio_uart_table,
and the insert/remove port from the table are symmetric. If
the BUG_ON occurs, which means serial_core modify the index
or mess up the port sequence anyway.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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 ce39f9d17c14 ("mmc: support packed write command for eMMC4.5
devices")
commit abd9ac144947 ("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>
|
