Commit Graph

697 Commits

Author SHA1 Message Date
Adrian Hunter d23029332c mmc: mmc: Improve reliability of mmc_select_hs400()
mmc_select_hs400() calls __mmc_switch() which checks the switch is
successful using CMD13 (SEND_STATUS).  The problem is that it does that
using the timing settings of the previous mode.  That is prone to error,
especially when switching from HS to HS400 because the timing parameters
for HS mode are tighter than the timing parameters for HS400 mode.

In the case when CMD13 polling is used (i.e. not MMC_CAP_WAIT_WHILE_BUSY)
with the switch command, it must be assumed that using different modes on
the card and host must work.

However in the case when CMD13 polling is not used
(i.e. MMC_CAP_WAIT_WHILE_BUSY) mmc_select_hs400() can be made more
reliable by setting the host to the correct timing before sending CMD13.

This patch does that.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: <stable@vger.kernel.org> # 4.2+
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-11-09 13:16:32 +01:00
Adrian Hunter 974007aaf2 mmc: mmc: Move mmc_switch_status()
Move the mmc_switch_status() function in preparation for calling it
in mmc_select_hs400().

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: <stable@vger.kernel.org> # 4.2+
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-11-09 13:16:26 +01:00
Adrian Hunter 51b12f7764 mmc: mmc: Fix HS setting in mmc_select_hs400()
mmc_select_hs400() begins with the card and host in HS200 mode.
Therefore, any commands sent to the card should use HS200 timing.
It is incorrect to set the host to High Speed (HS) timing before
sending the switch command.  Doing so is unreliable because
the timing parameters for HS mode are tighter than the timing
parameters for HS200 mode.  Thus the HS timings should be set
only after the card has switched mode.

However, it is not unreasonable first to reduce the frequency to
the HS mode frequency, which should make the switch command and
subsequent CMD13 commands more reliable.

This patch does that.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: <stable@vger.kernel.org> # 4.2+
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-11-09 13:16:20 +01:00
Adrian Hunter 1815e61b1a mmc: mmc: Improve reliability of mmc_select_hs200()
Currently mmc_select_hs200() uses __mmc_switch() which checks the
success of the switch to HS200 mode using CMD13 (SEND_STATUS).
The problem is that it does that using the timing settings of legacy
mode.  That is prone to error, not least because the timing parameters
for legacy mode are tighter than the timing parameters for HS200 mode.

In the case when CMD13 polling is used (i.e. not MMC_CAP_WAIT_WHILE_BUSY)
with the switch command, it must be assumed that using different modes on
the card and host must work.

However in the case when CMD13 polling is not used
(i.e. MMC_CAP_WAIT_WHILE_BUSY) mmc_select_hs200() can be made more
reliable by setting the host to the correct timing before sending CMD13.

This patch does that.

A complication is that the caller, mmc_select_timing(), will ignore a
switch error (indicated by -EBADMSG), assume the old mode is valid
and continue, so the old timing must be restored in that case.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: <stable@vger.kernel.org> # 4.2+
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-11-09 13:12:08 +01:00
Javier Martinez Canillas 1c6e58d836 mmc: pwrseq: Use highest priority for eMMC restart handler
The pwrseq_emmc driver does a eMMC card reset before a system reboot to
allow broken or limited ROM boot-loaders (that don't have an eMMC reset
logic) to be able to read the second stage from the eMMC.

But this has to be called before a system reboot handler and while most
of them use the priority 128, there are other restart handlers (such as
the syscon-reboot one) that use a higher priority. So, use the highest
priority to make sure that the eMMC hw is reset before a system reboot.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Markus Reichl <m.reichl@fivetechno.de>
Tested-by: Anand Moon <linux.amoon@gmail.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Tested-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-27 11:11:06 +01:00
Chaotian Jing 9979dbe515 mmc: mmc: extend the mmc_send_tuning()
The mmc_execute_tuning() has already prepared the opcode,
there is no need to prepare it again at mmc_send_tuning(),
and, there is a BUG of mmc_send_tuning() to determine the opcode
by bus width, assume eMMC was running at HS200, 4bit mode,
then the mmc_send_tuning() will overwrite the opcode from CMD21
to CMD19, then got error.

in addition, extend an argument of "cmd_error" to allow getting
if there was cmd error when tune response.

Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
[Ulf: Rebased patch]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-27 10:38:41 +01:00
Chaotian Jing 794f15782d mmc: core: Add DT bindings for eMMC hardware reset support
Sometime only need set MMC_CAP_HW_RESET for one of MMC hosts,
So set it in device tree is better.

Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-27 10:21:15 +01:00
Sergei Shtylyov 2860d060ac mmc: skip reclaiming host on mmc_add_card() error
There's little sense in releasing the host on mmc_add_card() error
immediately after reclaiming  it, so reclaim the host  only in case
of success.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-26 16:00:14 +01:00
Douglas Anderson 2086f801cb mmc: core: Add mmc_regulator_set_vqmmc()
This adds logic to the MMC core to set VQMMC.  This is expected to be
called by MMC drivers like dw_mmc as part of (or instead of) their
start_signal_voltage_switch() callback.

A few notes:

* When setting the signal voltage to 3.3V we do our best to make VQMMC
  and VMMC match.  It's been reported that this makes some old cards
  happy since they were tested back in the day before UHS when VQMMC
  and VMMC were provided by the same regulator.  A nice side effect of
  this is that we don't end up on the hairy edge of VQMMC (2.7V),
  which some EEs claim is a little too close to the minimum for
  comfort.
  This is done in two steps. At first we try to find a VQMMC within
  a 0.3V tolerance of VMMC and if this is not supported by the
  supplying regulator we try to find a suitable voltage within the
  whole 2.7V-3.6V area of the spec.

* The two step approach is currently necessary, as the used
  regulator_set_voltage_triplet(min, target, max) uses a simple
  implementation that just tries two basic steps:
	regulator_set_voltage(target, max);
	regulator_set_voltage(min, target);
  So with only one step with 2.7-3.6V borders, if a suitable voltage
  is a bit below VMMC, we would directly get the lowest 2.7V
  which some boards (like Rockchips) don't like at all.

* When setting the signal voltage to 1.8V or 1.2V we aim for that
  specific voltage instead of picking the lowest one in the range.

* We very purposely don't print errors in mmc_regulator_set_vqmmc().
  There are cases where the MMC core will try several different
  voltages and we don't want to pollute the logs.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-26 16:00:10 +01:00
Heiko Stuebner 310c805e7f mmc: core: move ocr-bit to voltage translation into separate function
We will shortly need the calculation of an ocr-bit to the actual
voltage in a second place too, so move it from mmc_regulator_set_ocr
to a common function mmc_ocrbitnum_to_vdd to make that possible.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-26 16:00:10 +01:00
Ulf Hansson 9eadcc0581 mmc: core: Remove MMC_CLKGATE
MMC_CLKGATE was once invented to save power by gating the bus clock at
request inactivity. At that time it served its purpose. The modern way to
deal with power saving for these scenarios, is by using runtime PM.

Nowadays, several host drivers have deployed runtime PM, but for those
that haven't and which still cares power saving at request inactivity,
it's certainly time to deploy runtime PM as it has been around for several
years now.

To simplify code to mmc core and thus decrease maintenance efforts, this
patch removes all code related to MMC_CLKGATE.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2015-10-26 16:00:09 +01:00
Weijun Yang 4324f6de6d mmc: core: enable CMD19 tuning for DDR50 mode
As SD Specifications Part1 Physical Layer Specification Version
3.01 says, CMD19 tuning is available for unlocked cards in transfer
state of 1.8V signaling mode. The small difference between v3.00
and 3.01 spec means that CMD19 tuning is also available for DDR50
mode.

Signed-off-by: Weijun Yang <york.yang@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-26 16:00:03 +01:00
Shawn Lin 85f45058ee mmc: debugfs: implement ios show for SDR12 and SDR25
This patch add MMC_TIMING_UHS_SDR12 and MMC_TIMING_UHS_SDR25
for mmc_ios_show to show the ios->timing if mmc card runs under
these two modes.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-26 16:00:02 +01:00
Hans de Goede 5d3f6ef04d mmc: Wait for card_busy before starting sdio requests
Some sdio wifi chips will not work properly if we try to start new
sdio-rw requests while the device is signalling that it is busy.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-26 16:00:01 +01:00
Hans de Goede de98c55682 mmc: Add mmc_is_io_op helper function
Add a helper function to check if an opcode is a sd-io-rw-* opcode.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-26 16:00:01 +01:00
Javier Martinez Canillas ce03727586 mmc: pwrseq_simple: use GPIO descriptors array API
The simple power sequence provider sets a value for multiple GPIOs in one
go so it is better to use the API already provided by the GPIO descriptor
API instead of open coding the same logic.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-26 15:59:59 +01:00
Shawn Lin d1f23f9304 mmc: debugfs: implement ios show for driver type
This patch add ios->drv_type for mmc_ios_show to show the
card's driver type.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-26 15:59:58 +01:00
Javier Martinez Canillas a30b55119d mmc: pwrseq: use gpiod_get() instead of index 0
The gpiod_get() function expands to gpiod_get_index() with index 0
so it's better to use it since is easier to read and more concise.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-26 15:59:55 +01:00
Ulf Hansson f90d2e4035 mmc: core: Convert __mmc_switch() into an internal core function
As there are no users of the __mmc_switch() API, except for the mmc core
itself, let's convert it from an exported function into an internal.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-26 15:59:54 +01:00
Yousong Zhou bf8b8511af mmc: sd: Remove superfluous error code assignment
Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-26 15:59:53 +01:00
Ulf Hansson 8d1ffc8c98 mmc: core: Keep host claimed while invoking mmc_power_off|up()
As mmc_claim_host() invokes pm_runtime_get_sync() for the mmc host device,
it's important that the host is kept claimed for *all* accesses to it via
the host_ops callbacks.

In some code paths for SDIO, particularly related to the PM support,
mmc_power_off|up() is invoked without keeping the host claimed. Let's fix
these.

Moreover, mmc_start|stop_host() also invokes mmc_power_off|up() without
claiming the host, let's fix these as well.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
2015-10-26 15:59:52 +01:00
Chaotian Jing 08b137d90e mmc: core: Fix init_card in 52Mhz
Suppose that we got a data crc error, and it triggers the mmc_reset.
mmc_reset will call mmc_send_status to see if HW reset was supported.
before issue CMD13, it will do retune, and if EMMC was in HS400 mode,
it will reduce frequency to 52Mhz firstly, then results in card init
was doing at 52Mhz.
The mmc_send_status was originally only done for mmc_test, should drop
it. And, rename the "eMMC hardware reset" to "Reset test", as we would
also be able to use the test for SD-cards.

Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
Suggested-by: Adrian Hunter <adrian.hunter@intel.com>
Fixes: bd11e8bd03 ("mmc: core: Flag re-tuning is needed on CRC errors")
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-10-21 10:18:11 +02:00
Chaotian Jing 031277d4d3 mmc: core: fix dead loop of mmc_retune
When get a CRC error, start the mmc_retune, it will issue CMD19/CMD21
to do tune, assume there were 10 clock phase need to try, phase 0 to
phase 6 is ok, phase 7 to phase 9 is NG, we try it from 0 to 9, so
the last CMD19/CMD21 will get CRC error, host->need_retune was set and
cause mmc_retune was called, then dead loop of mmc_retune

Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Fixes: bd11e8bd03 ("mmc: core: Flag re-tuning is needed on CRC errors")
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-09-30 14:54:22 +02:00
Ulf Hansson 43934ece2e mmc: core: Don't return an error for CD/WP GPIOs when GPIOLIB is unset
When CONFIG_GPIOLIB is unset, its stubs will return -ENOSYS. That means
when the mmc core parses DT for CD/WP GPIOs via mmc_of_parse(), -ENOSYS
becomes propagated to the caller. Typically this means that the mmc host
driver fails to probe.

As the CD/WP GPIOs are already treated as optional, let's extend that to
cover the case when CONFIG_GPIOLIB is unset.

Reported-by: Michal Simek <michal.simek@xilinx.com>
Fixes: 16b23787fc ("mmc: sdhci-of-arasan: Call OF parsing for MMC")
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Venu Byravarasu <vbyravarasu@nvidia.com>
2015-09-29 12:17:03 +02:00
Jialing Fu 71f8a4b81d mmc: core: fix race condition in mmc_wait_data_done
The following panic is captured in ker3.14, but the issue still exists
in latest kernel.
---------------------------------------------------------------------
[   20.738217] c0 3136 (Compiler) Unable to handle kernel NULL pointer dereference
at virtual address 00000578
......
[   20.738499] c0 3136 (Compiler) PC is at _raw_spin_lock_irqsave+0x24/0x60
[   20.738527] c0 3136 (Compiler) LR is at _raw_spin_lock_irqsave+0x20/0x60
[   20.740134] c0 3136 (Compiler) Call trace:
[   20.740165] c0 3136 (Compiler) [<ffffffc0008ee900>] _raw_spin_lock_irqsave+0x24/0x60
[   20.740200] c0 3136 (Compiler) [<ffffffc0000dd024>] __wake_up+0x1c/0x54
[   20.740230] c0 3136 (Compiler) [<ffffffc000639414>] mmc_wait_data_done+0x28/0x34
[   20.740262] c0 3136 (Compiler) [<ffffffc0006391a0>] mmc_request_done+0xa4/0x220
[   20.740314] c0 3136 (Compiler) [<ffffffc000656894>] sdhci_tasklet_finish+0xac/0x264
[   20.740352] c0 3136 (Compiler) [<ffffffc0000a2b58>] tasklet_action+0xa0/0x158
[   20.740382] c0 3136 (Compiler) [<ffffffc0000a2078>] __do_softirq+0x10c/0x2e4
[   20.740411] c0 3136 (Compiler) [<ffffffc0000a24bc>] irq_exit+0x8c/0xc0
[   20.740439] c0 3136 (Compiler) [<ffffffc00008489c>] handle_IRQ+0x48/0xac
[   20.740469] c0 3136 (Compiler) [<ffffffc000081428>] gic_handle_irq+0x38/0x7c
----------------------------------------------------------------------
Because in SMP, "mrq" has race condition between below two paths:
path1: CPU0: <tasklet context>
  static void mmc_wait_data_done(struct mmc_request *mrq)
  {
     mrq->host->context_info.is_done_rcv = true;
     //
     // If CPU0 has just finished "is_done_rcv = true" in path1, and at
     // this moment, IRQ or ICache line missing happens in CPU0.
     // What happens in CPU1 (path2)?
     //
     // If the mmcqd thread in CPU1(path2) hasn't entered to sleep mode:
     // path2 would have chance to break from wait_event_interruptible
     // in mmc_wait_for_data_req_done and continue to run for next
     // mmc_request (mmc_blk_rw_rq_prep).
     //
     // Within mmc_blk_rq_prep, mrq is cleared to 0.
     // If below line still gets host from "mrq" as the result of
     // compiler, the panic happens as we traced.
     wake_up_interruptible(&mrq->host->context_info.wait);
  }

path2: CPU1: <The mmcqd thread runs mmc_queue_thread>
  static int mmc_wait_for_data_req_done(...
  {
     ...
     while (1) {
           wait_event_interruptible(context_info->wait,
                   (context_info->is_done_rcv ||
                    context_info->is_new_req));
     	   static void mmc_blk_rw_rq_prep(...
           {
           ...
           memset(brq, 0, sizeof(struct mmc_blk_request));

This issue happens very coincidentally; however adding mdelay(1) in
mmc_wait_data_done as below could duplicate it easily.

   static void mmc_wait_data_done(struct mmc_request *mrq)
   {
     mrq->host->context_info.is_done_rcv = true;
+    mdelay(1);
     wake_up_interruptible(&mrq->host->context_info.wait);
    }

At runtime, IRQ or ICache line missing may just happen at the same place
of the mdelay(1).

This patch gets the mmc_context_info at the beginning of function, it can
avoid this race condition.

Signed-off-by: Jialing Fu <jlfu@marvell.com>
Tested-by: Shawn Lin <shawn.lin@rock-chips.com>
Fixes: 2220eedfd7 ("mmc: fix async request mechanism ....")
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-08-31 09:20:16 +02:00
Shawn Lin b5b4ff0a63 mmc: block: skip trim for some kingston eMMCs
For some mass production of kingston eMMCs which adopt Phison's
firmware will meet an unrecoverable data conrruption occasionally
if performing trim due to a firmware bug confirmed by vendor. We
found it on Intel-C3230RK platform. So we add fixup of broken trim
for it.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-08-27 14:50:52 +02:00
Sergei Shtylyov 90614cd904 mmc: host: use of_property_read_bool()
Use more compact of_property_read_bool() calls instead of the
of_find_property() calls.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-08-27 14:50:48 +02:00
Robin van der Gracht 22d7e85ff8 mmc: core: Fixed bug in one erase-group budget TRIM
When requesting a trim for several bytes, everything up to the next
erase-group is erased. This causes data corruption.

Signed-off-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-08-27 14:50:47 +02:00
David Jander 642c28ab86 mmc: core: Optimize case for exactly one erase-group budget
In the (not so unlikely) case that the mmc controller timeout budget is
enough for exactly one erase-group, the simplification of allowing one
sector has an enormous performance penalty. We optimize this special case
by introducing a flag that prohibits erase-group boundary crossing, so
that we can allow trimming more than one sector at a time.

Signed-off-by: David Jander <david@protonic.nl>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-08-17 11:32:39 +02:00
Ulf Hansson 1ef48e3ded mmc: core: Attach PM domain prior probing of SDIO func driver
Other subsystem buses attach PM domains during probe, but prior calling
the driver's ->probe() method. During the removal phase, detaching the PM
domain will be done after invoking the driver's ->remove() callback.

Convert the SDIO bus to follow this behavior and add error handling.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-04 10:03:51 +02:00
Ulf Hansson 3056c49c35 mmc: core: Remove redundant ->power_restore() callback for SD
Since the ->reset() callback is implemented for SD, the ->power_restore()
callback has become redundant, let's remove it.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-04 10:03:51 +02:00
Ulf Hansson 364549ddc2 mmc: core: Remove redundant ->power_restore() callback for MMC
Since the ->reset() callback is implemented for MMC, the ->power_restore()
callback has become redundant, let's remove it.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-04 10:03:51 +02:00
Adrian Hunter cc4f414c88 mmc: mmc: Add driver strength selection
Add the ability to set eMMC driver strength
for HS200 and HS400.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:07:14 +02:00
Adrian Hunter b097e07f57 mmc: mmc: Read card's valid driver strength mask
In preparation for supporing drive strength selection
for eMMC, read the card's valid driver strengths.

Note that though the SD spec uses the term "drive strength",
the JEDEC eMMC spec uses the term "driver strength".

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:07:13 +02:00
Adrian Hunter 3853a04232 mmc: core: Record card drive strength
In preparation for adding drive strength support
for eMMC, add drive_strength to struct mmc_card
to record the card drive strength for UHS-I modes
and HS200 / HS400. For eMMC this will be needed
when switching between HS200 and HS400.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:07:13 +02:00
Adrian Hunter e23350b35d mmc: core: Factor out common code in drive strength selection
Make a new function out of common code used for drive
strength selection.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:07:12 +02:00
Adrian Hunter f168359efb mmc: core: Add 'card' to drive strength selection callback
In preparation for supporting also eMMC drive strength,
add the 'card' as a parameter so that the callback can
distinguish different types of cards if necessary.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:07:12 +02:00
Adrian Hunter fa021cef1a mmc: core: Simplify card drive strength mask
Card drive strength selection uses a callback to
which a mask of supported drive strengths is passed.
Currently, the bits are checked against the values
in the SD specifications. That is not necessary
because the callback will anyway match the mask
against a valid value. Simplify by taking the mask
as is but still ensuring that the default mandatory
value (type B) is always supported.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:07:11 +02:00
Adrian Hunter b4f30a174e mmc: core: Allow card drive strength to be different to host
Initialization of UHS-I modes for SD and SDIO cards
employs a callback to allow the host driver to
choose a drive strength value. Currently that
assumes the card drive strength and host driver
type must be the same value. Change to let the
callback make that decision and return both the
card drive strength and host driver type.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:07:11 +02:00
Adrian Hunter 75e8a2288c mmc: core: Reset driver type to default
IO state variable drv_type could be set during card
initialization. Consequently, it must be reset to the
default value when setting the initial state.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:07:10 +02:00
Doug Anderson 7c5209c315 mmc: core: Increase delay for voltage to stabilize from 3.3V to 1.8V
Since the regulator used for the SDMMC IO voltage is not expected to
draw a lot of current, most systems will probably use an inexpensive
LDO for it.  LDO regulators apparently have the feature that they
don't actively drive the voltage down--they wait for other components
in the system to drag the voltage down.  Thus they will transition
faster under heavy loads and slower under light loads.

During an SDMMC voltage change from 3.3V to 1.8V, we are almost
certainly under a light load.  To be specific:
* The regulator is hooked through pulls to CMD0-3 and DAT.  Probably
  the CMD pulls are something like 47K and the DAT is something like
  10K.
* The card is supposed to be driving DAT0-3 low during voltage change
  which will draw _some_ current, but not a lot.
* The regulator is also provided to the SDMMC host controller, but the
  SDMMC host controller is in open drain mode during the voltage
  change and so shouldn't be drawing much current.

In order to keep the SDMMC host working properly (or for noise
reasons), there might also be a capacitor attached to the SDMMC IO
regulator.  This also will have the effect of slowing down transitions
of the regulator, especially under light loads.

From experimental evidence, we've seen the voltage change fail if the
card doesn't detect that the voltage fell to less than about 2.3V when
we turn on the clock.  On one device (that admittedly had a 47K CMD
pullup instead of a 10K CMD pullup) we saw that the voltage was just
about 2.3V after 5ms and thus the voltage change would sometimes fail.
Doubling the delay gave margin and made the voltage change work 100%
of the time, despite the slightly weaker CMD pull.

At the moment submitting this as an RFC patch since my problem _could_
be fixed by increasing the pull strength (or using a smaller
capacitor).  However being a little bit more lenient to strange
hardware could also be a good thing.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:07:07 +02:00
Kuninori Morimoto ded8a5f961 mmc: cast u8 to unsigned long long to avoid unexpected error
card->ext_csd.enhanced_area_offset is defined as "unsigned long long",
and, ext_csd[] is defined as u8.
unsigned long long data might have strange data if first bit of ext_csd[]
was 1. this patch cast it to (unsigned long long)
Special thanks to coverity <http://www.coverity.com>

ex)
        u8  data8;
        u64 data64;

        data8 = 0x80;
        data64 = (data8 << 24); // 0xffffffff80000000
        data64 = (((unsigned long long)data8) << 24); // 0x80000000;

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:07:03 +02:00
Lars-Peter Clausen 19f4424677 mmc: dt: Allow to specify that no write protect signal is present
Allow to specify in the device-tree that no physical write-protect signal
is connected to a particular instance of a MMC controller. Setting the
property will cause the core will assume that the SD card is always
read-write.

The name for the new property is 'disable-wp' and was chosen based on the
property with the same function from the Synopsys designware mobile storage
host controller DT bindings specification.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Kumar Gala <galak@codeaurora.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:07:00 +02:00
Lars-Peter Clausen 9f6e0bff2a mmc: Add support for disabling write-protect detection
It is not uncommon to see systems where there is no physical write-protect
signal (e.g. when using eMMC or microSD card slots). For some controllers,
which have a dedicated write-protection detection logic (like SDHCI
controllers), the get_ro() callback can return bogus data in such a case.

Instead of handling this on a per controller basis this patch adds a new
capability flag to the MMC core that can be set to specify that the result
of get_ro() is invalid. When the flag is set the core will not call
get_ro() and assume that the card is always read-write.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:06:59 +02:00
Adrian Hunter 0250fdf257 mmc: core: Don't print reset warning if reset is not supported
Check the error code for EOPNOTSUPP and do not print
reset warning in that case.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:06:59 +02:00
Adrian Hunter bd11e8bd03 mmc: core: Flag re-tuning is needed on CRC errors
CRC errors could possibly be alleviated by
re-tuning so flag re-tuning needed in those cases.
Note this has no effect if re-tuning has not been
enabled.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:06:58 +02:00
Adrian Hunter 6376f69d20 mmc: core: Add support for HS400 re-tuning
HS400 re-tuning must be done in HS200 mode. Add
the ability to switch from HS400 mode to HS200
mode before re-tuning and switch back to HS400
after re-tuning.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:06:57 +02:00
Adrian Hunter ed16f58dc0 mmc: core: Separate out the mmc_switch status check so it can be re-used
Make a separate function to do the mmc_switch status check
so it can be re-used. This is preparation for adding support
for HS400 re-tuning.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:06:56 +02:00
Adrian Hunter 436f8daa6f mmc: mmc: Hold re-tuning in mmc_sleep()
The sleep command is issued after deselecting the
card, but re-tuning won't work on a deselected card
so re-tuning must be held.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:06:56 +02:00
Adrian Hunter 66073d8671 mmc: core: Hold re-tuning while bkops ongoing
Hold re-tuning during bkops to prevent
it from conflicting with the busy state.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-06-01 09:06:55 +02:00