The ux500 variant doesn't have a HW based timeout to use for busy-end IRQs.
To avoid hanging and waiting for the card to stop signaling busy, let's
schedule a delayed work, according to the corresponding cmd->busy_timeout
for the command. If the work gets to run, let's kick the IRQ handler to
complete the currently running request/command.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20230620091113.33393-1-ulf.hansson@linaro.org
In stm32 sdmmc variant revision v3.0, a block gap hardware flow control
should be used with bus speed modes SDR104 and HS200.
It is enabled by writing a non-null value to the new added register
MMCI_STM32_FIFOTHRR.
The threshold will be 2^(N-1) bytes, so we can use the ffs() function to
compute the value N to be written to the register. The threshold used
should be the data block size, but must not be bigger than the FIFO size.
Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
Link: https://lore.kernel.org/r/20230619115120.64474-5-yann.gautier@foss.st.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The alignment for the IDMA size depends on the peripheral version, it
should then be configurable. Add stm32_idmabsize_align in the variant
structure.
And remove now unused (and wrong) MMCI_STM32_IDMABNDT_* macros.
Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
Link: https://lore.kernel.org/r/20230619115120.64474-3-yann.gautier@foss.st.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This refactors the ->busy_complete() callback currently
only used by Ux500 and STM32 to handle busy detection on
hardware where one and the same IRQ is fired whether we get
a start or an end signal on busy detect.
The code is currently using the cached status from the
command IRQ in ->busy_status as a state to select what to
do next: if this state is non-zero we are waiting for
IRQs and if it is zero we treat the state as the starting
point for a busy detect wait cycle.
Make this explicit by creating a state machine where the
->busy_complete callback moves between three states.
The Ux500 busy detect code currently assumes this order:
we enable the busy detect IRQ, get a busy start IRQ, then a
busy end IRQ, and then we clear and mask this IRQ and
proceed.
We insert debug prints for unexpected states.
This works as before on most cards, however on a
problematic card that is not working with busy detect, and
which I have been debugging, the following happens a lot:
[ 3.380554] mmci-pl18x 80005000.mmc: no busy signalling in time
[ 3.387420] mmci-pl18x 80005000.mmc: no busy signalling in time
[ 3.394561] mmci-pl18x 80005000.mmc: lost busy status
when waiting for busy start IRQ
This probably means that the busy detect start IRQ has
already occurred when we start executing the
->busy_complete() callbacks, and the busy detect end IRQ
is counted as the start IRQ, and this is what is causing
the card to not be detected properly.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230405-pl180-busydetect-fix-v7-5-69a7164f2a61@linaro.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
To prepare the voltage switch procedure, the VSWITCHEN bit must be set
before sending the CMD11. To confirm completion of voltage switch, the
VSWEND flag must be checked.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Link: https://lore.kernel.org/r/20200128090636.13689-9-ludovic.barre@st.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
A variant may need to define some actions before and after a voltage
switch.
This patch adds 2 callbacks to manage signal voltage switch in the struct
mmci_host_ops. ->pre_sig_volt_switch() allows to prepare a signal voltage
switch before sending the SD_SWITCH_VOLTAGE command (CMD11).
->post_sig_volt_switch callback allows specific actions to be executed,
after the I/O signal voltage level has been changed.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Link: https://lore.kernel.org/r/20200128090636.13689-8-ludovic.barre@st.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
In variant init function, some references may be allocated for variant
specific usage. Add a private void* to mmci_host struct allows at variant
functions to access on this references by mmci_host structure.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Link: https://lore.kernel.org/r/20200128090636.13689-5-ludovic.barre@st.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The variant init function may need to add a mmc_host_ops, for example to
add the execute_tuning support if this feature is available. This patch
adds mmc_host_ops pointer in mmci struct.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Link: https://lore.kernel.org/r/20200128090636.13689-4-ludovic.barre@st.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
For the ux500v2 variant of the PL18x block, any block sizes
are supported. This is necessary to support some SDIO
transfers. This also affects the QCOM MMCI variant and the
ST micro variant.
For Ux500 an additional quirk only allowing DMA on blocks
that are a power of two is needed. This might be a bug in
the DMA engine (DMA40) or the MMCI or in the interconnect,
but the most likely is the MMCI, as transfers of these
sizes work fine for other devices using the same DMA
engine. DMA works fine also with SDIO as long as the
blocksize is a power of 2.
This patch has proven necessary for enabling SDIO for WLAN on
PostmarketOS-based Ux500 platforms.
What we managed to test in practice is Broadcom WiFi over
SDIO on the Ux500 based Samsung GT-I8190 and GT-S7710.
This WiFi chip, BCM4334 works fine after the patch.
Before this patch:
brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac4334-sdio
for chip BCM4334/3
mmci-pl18x 80118000.sdi1_per2: unsupported block size (60 bytes)
brcmfmac: brcmf_sdiod_ramrw: membytes transfer failed
brcmfmac: brcmf_sdio_download_code_file: error -22 on writing
434236 membytes at 0x00000000
brcmfmac: brcmf_sdio_download_firmware: dongle image file download
failed
After this patch:
brcmfmac: brcmf_c_preinit_dcmds: Firmware: BCM4334/3 wl0:
Nov 21 2012 00:21:28 version 6.10.58.813 (B2) FWID 01-0
Bringing up networks, discovering networks with "iw dev wlan0 scan"
and connecting works fine from this point.
This patch is inspired by Ulf Hansson's patch
http://www.spinics.net/lists/linux-mmc/msg12160.html
As the DMA engines on these platforms may now get block sizes
they were not used to before, make sure to also respect if
the DMA engine says "no" to a transfer.
Make a drive-by fix for datactrl_blocksz, misspelled.
Cc: Ludovic Barre <ludovic.barre@st.com>
Cc: Brian Masney <masneyb@onstation.org>
Cc: Stephan Gerhold <stephan@gerhold.net>
Cc: Niklas Cassel <niklas.cassel@linaro.org>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Stephan Gerhold <stephan@gerhold.net>
Link: https://lore.kernel.org/r/20191217143952.2885-1-linus.walleij@linaro.org
The stm32_sdmmc variant has build-in support for datatimeout for R1B
requests. If a corresponding IRQ is raised, this triggers the DPSM to stay
busy and remains in a non-functional state. Only a reset can bring it back
to a functional state.
Because a reset must be issued from non-atomic context, let's defer this to
be managed from a threaded IRQ handler. Besides the reset, the threaded
handler also calls mmc_request_done(), to finally complete the request.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Link: https://lore.kernel.org/r/20191211133934.16932-1-ludovic.Barre@st.com
[Ulf: A few minor updates to the changelog/comments]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Let's drop the boilerplate code for managing the default pinctrl state and
convert into using the new pinctrl_select_default_state().
Additionally, move away from using pinctrl_pm_select_default_state() as
it's scheduled for removal and use pinctrl_select_default_state() instead.
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20191206170821.29711-4-ulf.hansson@linaro.org
This patch adds a specific busy_complete callback for sdmmc variant.
sdmmc has 2 status flags:
-busyd0: This is a hardware status flag (inverted value of d0 line).
it does not generate an interrupt.
-busyd0end: This indicates only end of busy following a CMD response.
On busy to Not busy changes, an interrupt is generated (if unmask)
and BUSYD0END status flag is set. Status flag is cleared by writing
corresponding interrupt clear bit in MMCICLEAR.
The legacy busy completion has no dedicated interrupt for the end
of busy, so it's must monitor step by step the busy progression.
On sdmmc variant, this procedure is not needed, it's just need
to wait the busyd0end interrupt.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds busy_completion callback at mmci_host_ops
to allow to define a specific busy completion by variant.
The legacy code corresponding to busy completion used
by ux500 variants is moved to ux500_busy_complete function.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
In the stm32_sdmmc variant, the datatimer is active not only during
data transfers with the DPSM, but also while waiting for the busyend
IRQs from commands having the MMC_RSP_BUSY flag set. This leads to an
incorrect IRQ being raised to signal MCI_DATATIMEOUT error, which
simply breaks the behaviour.
Address this by updating the datatimer value before sending a command
having the MMC_RSP_BUSY flag set. To inform the mmc core about the
maximum supported busy timeout, which also depends on the current
clock rate, set ->max_busy_timeout (in ms).
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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>
This patch allows to get datactrl configuration specific
at variant. This introduce more flexibility on datactlr
value.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch defines get_dctrl_cfg callback for sdmmc variant.
sdmmc variant has specific stm32 transfer modes.
sdmmc data transfer mode selection could be:
-Block data transfer ending on block count.
-SDIO multibyte data transfer.
-MMC Stream data transfer (not used).
-Block data transfer ending with STOP_TRANSMISSION command.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds get_datactrl_cfg callback in mmci_host_ops
to allow to get datactrl configuration specific at variant.
Common helper function is defined and could be call by variant.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
It's good practice to share functions via header files, rather than from
the c-files. Therefore, let's move sdmmc_variant_init() to mmci.h.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Ludovic Barre <ludovic.barre@st.com>
Tested-by: Ludovic Barre <ludovic.barre@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
It seems a bit silly to have a header file to share only the
qcom_variant_init() function. So, let's just drop it and move the
declaration of the function into the common mmci.h instead.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Some of the DMA functions are shared via mmci.h, however they are not
implemented unless CONFIG_DMA_ENGINE is set. Therefore, add that constraint
to the header file as well.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
The current approach with sending a CMD12 (STOP_TRANSMISSION) to complete a
data transfer request, either because of using the open-ended transmission
type or because of receiving an error during a pre-defined data transfer,
isn't sufficient for the STM32 sdmmc variant. More precisely, this variant
needs to clear the DPSM ("Data Path State Machine") by sending a CMD12, for
all failing ADTC commands.
Support this, by adding a struct mmc_command inside the struct mmci_host
and initialize it to a CMD12 during ->probe(). Let's also add checks for
the new conditions, to enable mmci_data_irq() and mmci_cmd_irq() to
postpone the calls to mmci_request_end(), but instead send the CMD12.
Cc: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Ludovic Barre <ludovic.barre@st.com>
On cmd12 (STOP_TRANSMISSION), STM32 sdmmc variant needs to set
cmdstop bit in command register. The CPSM ("Command Path State Machine")
treats the command as a Stop Transmission command and signals
abort to the DPSM ("Data Path State Machine").
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds a stm32 sdmmc variant, rev 1.1.
Introduces a new Manufacturer id "0x53, ascii 'S' to define
new stm32 sdmmc family with clean range of amba
revision/configurations bits (corresponding to sdmmc_ver
register with major/minor fields).
Add 2 variants properties:
-dma_lli, to enable link list support.
-stm32_idmabsize_mask, defines the range of SDMMC_IDMABSIZER register
which specify the number bytes per buffer.
DT properties for sdmmc:
-Indicate signal directions (only one property
for d0dir, d123dir, cmd_dir)
-Select command and data phase relation.
-Select "clock in" from an external driver.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The STM32 sdmmc variant has a different clock divider.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds a optional reset management.
STM32 sdmmc variant needs to reset hardware block
during the power cycle procedure (for re-initialization).
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds a boolean property to not read datacnt register.
Needed to support the STM32 sdmmc variant. MMCIDATACNT
register should be read only after the data transfer is completed.
When reading after an error event the read data count value may be
different from the real number of data bytes transferred.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds a boolean property to allow to write datactrl
before to send command, whatever the command type (read or write).
Needed to support the STM32 sdmmc variant.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch allows to define specific pio mask for variants.
Needed to support the STM32 sdmmc variant which has some bits
with different meaning (bits: 21,20,13,12,9)
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds datactrl variant property to define
dpsm enable bit. Needed to support the STM32 variant
(STM32 has no dpsm enable bit).
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds command variant properties to define
cpsm enable bit and responses.
Needed to support the STM32 variant (shift of cpsm bit,
specific definition of commands response).
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
All variants don't pretend to have a startbiterr.
-While data error check, if status register return an error
(like MCI_DATACRCFAIL) we must avoid to check MCI_STARTBITERR
(if not desired).
-expand start_err to MCI_IRQENABLE to avoid to set this bit by default.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch allows to define a datactrl block size
by variant, requested by STM32 sdmmc variant.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds set_clkreg and set_pwrreg callbacks
at mmci_host_ops to allow to call specific variant.
extends visibility of mmci_write_clk/pwrreg functions
to be used into specific file variant.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds validate_data callback at mmci_host_ops
to check specific constraints of variant.
Move mmci_validate_data function to regroup mmci_host_ops interfaces.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds dma_error callback at mmci_host_ops
to allow to call specific variant.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds dma_finalize callback at mmci_host_ops
to allow to call specific variant.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds dma_start callback to mmci_host_ops.
Create a generic mmci_dma_start function which regroup
common action between variant.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch adds prepare/unprepare callbacks to mmci_host_ops.
Like this mmci_pre/post_request can be generic, mmci_prepare_data
and mmci_unprepare_data provide common next_cookie management.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
-Introduces dma_priv pointer to define specific
needs for each dma engine. This patch is needed to prepare
sdmmc variant with internal dma which not use dmaengine API.
-Moves next cookie to mmci host structure to share same cookie
management between all variants.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch creates a common mmci_dma_setup/release which calls
dma_setup/release callbacks of mmci_host_ops and manages
common features like use_dma... If there is a fallbacks to
pio mode, dma functions must check use_dma.
error management:
-mmci_dmae_setup fail if Tx and Rx dma channels are not defined
-qcom_dma_setup fail if one of both dma channels is not defined,
Qcom has no specific resource to release, just mmci dmae resource.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Recent versions of checkpatch have a new warning based on a documented
preference of Linus to not use bool in structures due to wasted space and
the size of bool is implementation dependent. For more information, see
the email thread at https://lkml.org/lkml/2017/11/21/384
fix checkpatch --strict issues:
-CHECK: Avoid using bool structure members because of possible alignment
issues - see: https://lkml.org/lkml/2017/11/21/384
-WARNING: Avoid using bool as bitfield. Prefer bool bitfields as
unsigned int or u<8|16|32>
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This patch internalizes the dma_inprogress into mmci dma interfaces.
This allows to simplify and prepare the next dma callbacks
for mmci host ops. dma_inprogress is called in mmci_dma_data_error
and mmci_dma_finalize.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
As a first step to improve the variant specific code for mmci, add a
->dma_setup() callback to the struct mmci_host_ops.
To show its use, let's deploy the callback for the qcom dml, which involves
also to the assign the mmci_host_ops pointer from the variant ->init()
callback.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Ludovic Barre <ludovic.barre@st.com>
To be able to better support different mmci variants, we need to be able to
use variant specific callbacks, rather than continue to sprinkle the code
with additional variant data. To move in this direction, let's add an
optional ->init() callback to the variant data struct, which variants shall
use to assign the mmci_host_ops pointer.
Using an ->init() callback enables us to partition the code between
different files. To allow separate mmci variant files to implement the
variant specifics, let's also move the definition of the struct
variant_data to the common mmci header file.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Ludovic Barre <ludovic.barre@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
If variant hasn't the control bit to switch pads in opendrain mode,
we can achieve the same result by asking to the pinmux driver to
configure pins for us.
This patch make the mmci driver able to do this whenever needed.
Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Two mask registers are used in order to select which events have to
actually generate an interrupt on each IRQ line.
It seems that in the single-IRQ case it's assumed that the IRQs lines
are simply OR-ed, while the two mask registers are still present. The
driver still programs the two mask registers separately.
However the STM32 variant has only one IRQ, and also has only one mask
register.
This patch prepares for STM32 variant support by making the driver using
only one mask register.
This patch also optimize the MMCIMASK1 mask usage by caching it into
host->mask1_reg which avoid to read it into mmci_irq().
Tested only on STM32 variant. RFT for variants other than STM32
Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
commit 64b12a68a9
"mmc: core: fix prepared requests while doing bkops"
is fixing a bug in the wrong way. A bug in the MMCI
device driver is fixed by amending the MMC core.
Thinking about it: what the pre- and post-callbacks
are doing is to essentially map and unmap SG lists
for DMA transfers. Why would we not be able to do that
just because a BKOPS command is sent inbetween?
Having to unprepare/prepare the next asynchronous
request for DMA seems wrong.
Looking the backtrace in that commit we can see what
the real problem actually is:
mmci_data_irq() is calling mmci_dma_unmap() twice
which is goung to call arm_dma_unmap_sg() twice
and v7_dma_inv_range() twice for the same sglist
and that will crash.
This happens because a request is prepared, then
a BKOPS is sent. The IRQ completing the BKOPS command
goes through mmci_data_irq() and thinks that a DMA
operation has just been completed because
dma_inprogress() reports true. It then proceeds to
unmap the sglist.
But that was wrong! dma_inprogress() should NOT be
true because no DMA was actually in progress! We had
just prepared the sglist, and the DMA channel
dma_current has been configured, but NOT started!
Because of this, the sglist is already unmapped when
we get our actual data completion IRQ, and we are
unmapping the sglist once more, and we get this crash.
Therefore, we need to revert this solution pushing
the problem to the core and causing problems, and
instead augment the implementation such that
dma_inprogress() only reports true if some DMA has
actually been started.
After this we can keep the request prepared during the
BKOPS and we need not unprepare/reprepare it.
Fixes: 64b12a68a9 ("mmc: core: fix prepared requests while doing bkops")
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
