linux-toradex.git/drivers/mmc/card/queue.c, branch v3.11

mmc: card: Adding support for sanitize in eMMC 4.5

2013-05-26T18:23:13+00:00

The sanitize support is added as a user-app ioctl call, and
was removed from the block-device request, since its purpose is
to be invoked not via File-System but by a user.

This feature deletes the unmap memory region of the eMMC card,
by writing to a specific register in the EXT_CSD.

unmap region is the memory region that was previously deleted
(by erase, trim or discard operation).

In order to avoid timeout when sanitizing large-scale cards,
the timeout for sanitize operation is 240 seconds.

Signed-off-by: Yaniv Gardi 
Signed-off-by: Maya Erez 
Signed-off-by: Chris Ball

mmc: block: fix the host's claim-release in special request

2013-03-22T17:29:36+00:00

For normal request mmc_blk_issue_rq is called twice with asynchronous
transfer(cur and prev). Host's claim and release can be done in each
mmc_blk_issue_rq. However, Special request is currently excluded in
asynchronous transfer. After special request is finished, if there is
no new request, mmc_release_host won't be called in mmc_blk_issue_rq.
The problem is founded during mmc_suspend.

[] (__schedule+0x0/0x78c) from [] (schedule+0x38/0x78)
[] (schedule+0x0/0x78) from [] (__mmc_claim_host+0xac/0x1b4)
[] (__mmc_claim_host+0x0/0x1b4) from [] (mmc_suspend+0x28/0x9c)
[] (mmc_suspend+0x0/0x9c) from [] (mmc_suspend_host+0xb4/0x194)
...

Reported-by: Johan Rudholm 
Signed-off-by: Seungwon Jeon 
Tested-by: Johan Rudholm 
Signed-off-by: Chris Ball

mmc: support packed write command for eMMC4.5 devices

2013-02-24T19:37:16+00:00

This patch supports packed write command of eMMC4.5 devices.  Several
writes can be grouped in packed command and all data of the individual
commands can be sent in a single transfer on the bus. Large amounts of
data in one transfer rather than several data of small size are
effective for eMMC write internally.  As a result, packed command help
write throughput be improved.  The following tables show the results
of packed write.

Type A:
test     none |  packed
iozone   25.8 |  31
tiotest  27.6 |  31.2
lmdd     31.2 |  35.4

Type B:
test     none |  packed
iozone   44.1 |  51.1
tiotest  47.9 |  52.5
lmdd     51.6 |  59.2

Type C:
test     none |  packed
iozone   19.5 |  32
tiotest  19.9 |  34.5
lmdd     22.8 |  40.7

Signed-off-by: Seungwon Jeon 
Reviewed-by: Maya Erez 
Reviewed-by: Namjae Jeon 
Signed-off-by: Chris Ball

mmc: fix async request mechanism for sequential read scenarios

2013-02-11T18:28:49+00:00

When current request is running on the bus and if next request fetched
by mmcqd is NULL, mmc context (mmcqd thread) gets blocked until the
current request completes. This means that if new request comes in while
the mmcqd thread is blocked, this new request can not be prepared in
parallel to current ongoing request. This may result in delaying the new
request execution and increase it's latency.

This change allows to wake up the MMC thread on new request arrival.
Now once the MMC thread is woken up, a new request can be fetched and
prepared in parallel to the current running request which means this new
request can be started immediately after the current running request
completes.

With this change read throughput is improved by 16%.

Signed-off-by: Konstantin Dorfman 
Reviewed-by: Seungwon Jeon 
Signed-off-by: Chris Ball

mmc: queue: exclude asynchronous transfer for special request

2013-02-11T18:28:48+00:00

Unlike normal r/w request, special requests(discard, flush)
is finished with a one-time issue_fn. Request change to
mqrq_prev makes unnecessary call.

Signed-off-by: Seungwon Jeon 
Reviewed-by: Konstantin Dorfman 
Signed-off-by: Chris Ball

mmc: queue: amend buffer swap for non-blocking transfer

2012-12-06T18:54:37+00:00

In case both 'req' and 'mq->mqrq_prev->req' are null, there is no request
to be processed. That means there is no need to switch buffer.
Switching buffer is required only after finishing 'issue_fn'.

Signed-off-by: Seungwon Jeon 
Reviewed-by: Per Forlin 
Tested-by: Johan Rudholm 
Signed-off-by: Chris Ball

mmc: queue: remove redundant memsets

2012-05-09T14:10:46+00:00

Not needed to memset, as they are pointers and are assigned
to proper values in the next line anyway.

Signed-off-by: Venkatraman S 
Reviewed-by: Namjae Jeon 
Signed-off-by: Chris Ball

mmc: queue: rename mmc_request function

2012-05-09T14:08:54+00:00

The name mmc_request is used for both the issue function
and a data structure, which creates conflicts in symbol lookups
in editors. Rename the function to mmc_request_fn.

Signed-off-by: Venkatraman S 
Reviewed-by: Namjae Jeon 
Signed-off-by: Chris Ball

mmc: fixes for eMMC v4.5 discard operation

2012-04-21T00:28:55+00:00

eMMC v4.5 discard operation is significantly different from the
existing trim operation because it is not guaranteed to work with
the new sanitize operation.  Consequently mmc_can_trim() is
separated from mmc_can_discard().

Also the new discard operation does not result in the sectors being
set to all-zeros, so discard_zeroes_data must not be set.

In addition, the new discard has the same timeout as trim, but from
v4.5 trim is defined to use the hc timeout.  The timeout calculation
is adjusted accordingly.

Fixes apply to linux 3.2 on.

Signed-off-by: Adrian Hunter 
Cc: 
Acked-by: Jaehoon Chung 
Acked-by: Linus Walleij 
Signed-off-by: Chris Ball

mmc: card: Kill block requests if card is removed

2012-01-12T04:58:44+00:00

Kill block requests when the host realizes that the card is
removed from the slot and is sure that subsequent requests
are bound to fail. Do this silently so that the block
layer doesn't output unnecessary error messages.

Signed-off-by: Sujit Reddy Thumma 
Acked-by: Adrian Hunter 
Signed-off-by: Chris Ball