commit 4bc31edebd upstream.
Way back in commit 4f25580fb8 ("mmc: core: changes frequency to
hs_max_dtr when selecting hs400es"), Rockchip engineers noticed that
some eMMC don't respond to SEND_STATUS commands very reliably if they're
still running at a low initial frequency. As mentioned in that commit,
JESD84-B51 P49 suggests a sequence in which the host:
1. sets HS_TIMING
2. bumps the clock ("<= 52 MHz")
3. sends further commands
It doesn't exactly require that we don't use a lower-than-52MHz
frequency, but in practice, these eMMC don't like it.
The aforementioned commit tried to get that right for HS400ES, although
it's unclear whether this ever truly worked as committed into mainline,
as other changes/refactoring adjusted the sequence in conflicting ways:
08573eaf1a ("mmc: mmc: do not use CMD13 to get status after speed mode
switch")
53e60650f7 ("mmc: core: Allow CMD13 polling when switching to HS mode
for mmc")
In any case, today we do step 3 before step 2. Let's fix that, and also
apply the same logic to HS200/400, where this eMMC has problems too.
Resolves errors like this seen when booting some RK3399 Gru/Scarlet
systems:
[ 2.058881] mmc1: CQHCI version 5.10
[ 2.097545] mmc1: SDHCI controller on fe330000.mmc [fe330000.mmc] using ADMA
[ 2.209804] mmc1: mmc_select_hs400es failed, error -84
[ 2.215597] mmc1: error -84 whilst initialising MMC card
[ 2.417514] mmc1: mmc_select_hs400es failed, error -110
[ 2.423373] mmc1: error -110 whilst initialising MMC card
[ 2.605052] mmc1: mmc_select_hs400es failed, error -110
[ 2.617944] mmc1: error -110 whilst initialising MMC card
[ 2.835884] mmc1: mmc_select_hs400es failed, error -110
[ 2.841751] mmc1: error -110 whilst initialising MMC card
Ealier versions of this patch bumped to 200MHz/HS200 speeds too early,
which caused issues on, e.g., qcom-msm8974-fairphone-fp2. (Thanks for
the report Luca!) After a second look, it appears that aligns with
JESD84 / page 45 / table 28, so we need to keep to lower (HS / 52 MHz)
rates first.
Fixes: 08573eaf1a ("mmc: mmc: do not use CMD13 to get status after speed mode switch")
Fixes: 53e60650f7 ("mmc: core: Allow CMD13 polling when switching to HS mode for mmc")
Fixes: 4f25580fb8 ("mmc: core: changes frequency to hs_max_dtr when selecting hs400es")
Cc: Shawn Lin <shawn.lin@rock-chips.com>
Link: https://lore.kernel.org/linux-mmc/11962455.O9o76ZdvQC@g550jk/
Reported-by: Luca Weiss <luca@z3ntu.xyz>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Tested-by: Luca Weiss <luca@z3ntu.xyz>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220422100824.v4.1.I484f4ee35609f78b932bd50feed639c29e64997e@changeid
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d6c9219ca1 ]
Even if the current WARN() notifies the user that something is severely
wrong, we can still end up in a PANIC() when trying to invoke the missing
->enable_sdio_irq() ops. Therefore, let's also return an error code and
prevent the host from being added.
While at it, move the code into a separate function to prepare for
subsequent changes and for further host caps validations.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20220303165142.129745-1-ulf.hansson@linaro.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 54309fde1a upstream.
On reads with MMC_READ_MULTIPLE_BLOCK that fail,
the recovery handler will use MMC_READ_SINGLE_BLOCK for
each of the blocks, up to MMC_READ_SINGLE_RETRIES times each.
The logic for this is fixed to never report unsuccessful reads
as success to the block layer.
On command error with retries remaining, blk_update_request was
called with whatever value error was set last to.
In case it was last set to BLK_STS_OK (default), the read will be
reported as success, even though there was no data read from the device.
This could happen on a CRC mismatch for the response,
a card rejecting the command (e.g. again due to a CRC mismatch).
In case it was last set to BLK_STS_IOERR, the error is reported correctly,
but no retries will be attempted.
Fixes: 81196976ed ("mmc: block: Add blk-mq support")
Cc: stable@vger.kernel.org
Signed-off-by: Christian Loehle <cloehle@hyperstone.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/bc706a6ab08c4fe2834ba0c05a804672@hyperstone.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 8c3e5b74b9 ]
The mmc core takes a specific path to support initializing of a
non-standard SDIO card. This is triggered by looking for the card-quirk,
MMC_QUIRK_NONSTD_SDIO.
In mmc_sdio_init_card() this gets rather messy, as it causes the code to
bail out earlier, compared to the usual path. This leads to that the OCR
doesn't get saved properly in card->ocr. Fortunately, only omap_hsmmc has
been using the MMC_QUIRK_NONSTD_SDIO and is dealing with the issue, by
assigning a hardcoded value (0x80) to card->ocr from an ->init_card() ops.
To make the behaviour consistent, let's instead rely on the core to save
the OCR in card->ocr during initialization.
Reported-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Link: https://lore.kernel.org/r/e7936cff7fc24d187ef2680d3b4edb0ade58f293.1636564631.git.hns@goldelico.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8fc9a77bc6 ]
The driver neglects to check the result of platform_get_irq()'s call and
blithely passes the negative error codes to devm_request_threaded_irq()
(which takes *unsigned* IRQ #), causing it to fail with -EINVAL, overriding
an original error code. Stop calling devm_request_threaded_irq() with the
invalid IRQ #s.
Fixes: ed80a13bb4 ("mmc: meson-mx-sdio: Add a driver for the Amlogic Meson8 and Meson8b SoC")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20211217202717.10041-3-s.shtylyov@omp.ru
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 77bed755e0 ]
The driver neglects to check the result of platform_get_irq()'s call and
blithely passes the negative error codes to devm_request_threaded_irq()
(which takes *unsigned* IRQ #), causing it to fail with -EINVAL, overriding
an original error code. Stop calling devm_request_threaded_irq() with the
invalid IRQ #s.
Fixes: e4bf1b0970 ("mmc: host: meson-mx-sdhc: new driver for the Amlogic Meson SDHC host")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20211217202717.10041-2-s.shtylyov@omp.ru
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit f89b548ca6 upstream.
The vendor driver implements special handling for multi-block
SD_IO_RW_EXTENDED (and SD_IO_RW_DIRECT) commands which have data
attached to them. It sets the MANUAL_STOP bit in the MESON_SDHC_MISC
register for these commands. In all other cases this bit is cleared.
Here we omit SD_IO_RW_DIRECT since that command never has any data
attached to it.
This fixes SDIO wifi using the brcmfmac driver which reported the
following error without this change on a Netxeon S82 board using a
Meson8 (S802) SoC:
brcmf_fw_alloc_request: using brcm/brcmfmac43362-sdio for chip
BCM43362/1
brcmf_sdiod_ramrw: membytes transfer failed
brcmf_sdio_download_code_file: error -110 on writing 219557 membytes
at 0x00000000
brcmf_sdio_download_firmware: dongle image file download failed
And with this change:
brcmf_fw_alloc_request: using brcm/brcmfmac43362-sdio for chip
BCM43362/1
brcmf_c_process_clm_blob: no clm_blob available (err=-2), device may
have limited channels available
brcmf_c_preinit_dcmds: Firmware: BCM43362/1 wl0: Apr 22 2013 14:50:00
version 5.90.195.89.6 FWID 01-b30a427d
Fixes: e4bf1b0970 ("mmc: host: meson-mx-sdhc: new driver for the Amlogic Meson SDHC host")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211219153442.463863-2-martin.blumenstingl@googlemail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0eab756f88 upstream.
There are several error return paths that dereference the null pointer
host because the pointer has not yet been set to a valid value.
Fix this by adding a new out_mmc label and exiting via this label
to avoid the host clean up and hence the null pointer dereference.
Addresses-Coverity: ("Explicit null dereference")
Fixes: 8105c2abbf ("mmc: moxart: Fix reference count leaks in moxart_probe")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20211013100052.125461-1-colin.king@canonical.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d806e334d0 ]
We need to restore context in a specified order with HCTL set in two
phases. This is similar to what omap_hsmmc_context_restore() is doing.
Otherwise SDIO can stop working on resume.
And for PM runtime and SDIO cards, we need to also save SYSCTL, IE and
ISE.
This should not be a problem currently, and these patches can be applied
whenever suitable.
Fixes: ee0f309263 ("mmc: sdhci-omap: Add Support for Suspend/Resume")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20210921110029.21944-3-tony@atomide.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8e0e7bd38b ]
If sdhci-omap is configured for an unused device instance and the device
is not set as disabled, we can get a NULL pointer dereference:
Unable to handle kernel NULL pointer dereference at virtual address
00000045
...
(regulator_set_voltage) from [<c07d7008>] (mmc_regulator_set_ocr+0x44/0xd0)
(mmc_regulator_set_ocr) from [<c07e2d80>] (sdhci_set_ios+0xa4/0x490)
(sdhci_set_ios) from [<c07ea690>] (sdhci_omap_set_ios+0x124/0x160)
(sdhci_omap_set_ios) from [<c07c8e94>] (mmc_power_up.part.0+0x3c/0x154)
(mmc_power_up.part.0) from [<c07c9d20>] (mmc_start_host+0x88/0x9c)
(mmc_start_host) from [<c07cad34>] (mmc_add_host+0x58/0x7c)
(mmc_add_host) from [<c07e2574>] (__sdhci_add_host+0xf0/0x22c)
(__sdhci_add_host) from [<c07eaf68>] (sdhci_omap_probe+0x318/0x72c)
(sdhci_omap_probe) from [<c06a39d8>] (platform_probe+0x58/0xb8)
AFAIK we are not seeing this with the devices configured in the mainline
kernel but this can cause issues for folks bringing up their boards.
Fixes: 7d326930d3 ("mmc: sdhci-omap: Add OMAP SDHCI driver")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20210921110029.21944-2-tony@atomide.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8105c2abbf ]
The issue happens in several error handling paths on two refcounted
object related to the object "host" (dma_chan_rx, dma_chan_tx). In
these paths, the function forgets to decrement one or both objects'
reference count increased earlier by dma_request_chan(), causing
reference count leaks.
Fix it by balancing the refcounts of both objects in some error
handling paths. In correspondence with the changes in moxart_probe(),
IS_ERR() is replaced with IS_ERR_OR_NULL() in moxart_remove() as well.
Signed-off-by: Xin Xiong <xiongx18@fudan.edu.cn>
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Link: https://lore.kernel.org/r/20211009041918.28419-1-xiongx18@fudan.edu.cn
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 162079f2dc ]
The Winbond MMC driver fails to build on ARCH=m68k so prevent
that build config. Silences these build errors:
../drivers/mmc/host/wbsd.c: In function 'wbsd_request_end':
../drivers/mmc/host/wbsd.c:212:28: error: implicit declaration of function 'claim_dma_lock' [-Werror=implicit-function-declaration]
212 | dmaflags = claim_dma_lock();
../drivers/mmc/host/wbsd.c:215:17: error: implicit declaration of function 'release_dma_lock'; did you mean 'release_task'? [-Werror=implicit-function-declaration]
215 | release_dma_lock(dmaflags);
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20211017175949.23838-1-rdunlap@infradead.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 43592c8736 upstream.
Only wait for DRTO on reads, otherwise the driver hangs.
The driver prevents sending CMD12 on response errors like CRCs. According
to the comment this is because some cards have problems with this during
the UHS tuning sequence. Unfortunately this workaround currently also
applies for any command with data. On reads this will set the drto timer,
which then triggers after a while. On writes this will not set any timer
and the tasklet will not be scheduled again.
I cannot test for the UHS workarounds need, but even if so, it should at
most apply to reads. I have observed many hangs when CMD25 response
contained a CRC error. This patch fixes this without touching the actual
UHS tuning workaround.
Signed-off-by: Christian Loehle <cloehle@hyperstone.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/af8f8b8674ba4fcc9a781019e4aeb72c@hyperstone.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9af372dc70 upstream.
To reset standard tuning circuit completely, after clear ESDHC_MIX_CTRL_EXE_TUNE,
also need to clear bit buffer_read_ready, this operation will finally clear the
USDHC IP internal logic flag execute_tuning_with_clr_buf, make sure the following
normal data transfer will not be impacted by standard tuning logic used before.
Find this issue when do quick SD card insert/remove stress test. During standard
tuning prodedure, if remove SD card, USDHC standard tuning logic can't clear the
internal flag execute_tuning_with_clr_buf. Next time when insert SD card, all
data related commands can't get any data related interrupts, include data transfer
complete interrupt, data timeout interrupt, data CRC interrupt, data end bit interrupt.
Always trigger software timeout issue. Even reset the USDHC through bits in register
SYS_CTRL (0x2C, bit28 reset tuning, bit26 reset data, bit 25 reset command, bit 24
reset all) can't recover this. From the user's point of view, USDHC stuck, SD can't
be recognized any more.
Fixes: d9370424c9 ("mmc: sdhci-esdhc-imx: reset tuning circuit when power on mmc card")
Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/1634263236-6111-1-git-send-email-haibo.chen@nxp.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 92b18252b9 upstream.
While mmc0 enter suspend state, we need halt CQE to send legacy cmd(flush
cache) and disable cqe, for resume back, we enable CQE and not clear HALT
state.
In this case MediaTek mmc host controller will keep the value for HALT
state after CQE disable/enable flow, so the next CQE transfer after resume
will be timeout due to CQE is in HALT state, the log as below:
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: timeout for tag 2
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: ============ CQHCI REGISTER DUMP ===========
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: Caps: 0x100020b6 | Version: 0x00000510
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: Config: 0x00001103 | Control: 0x00000001
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: Int stat: 0x00000000 | Int enab: 0x00000006
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: Int sig: 0x00000006 | Int Coal: 0x00000000
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: TDL base: 0xfd05f000 | TDL up32: 0x00000000
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: Doorbell: 0x8000203c | TCN: 0x00000000
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: Dev queue: 0x00000000 | Dev Pend: 0x00000000
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: Task clr: 0x00000000 | SSC1: 0x00001000
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: SSC2: 0x00000001 | DCMD rsp: 0x00000000
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: RED mask: 0xfdf9a080 | TERRI: 0x00000000
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: Resp idx: 0x00000000 | Resp arg: 0x00000000
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: CRNQP: 0x00000000 | CRNQDUN: 0x00000000
<4>.(4)[318:kworker/4:1H]mmc0: cqhci: CRNQIS: 0x00000000 | CRNQIE: 0x00000000
This change check HALT state after CQE enable, if CQE is in HALT state, we
will clear it.
Signed-off-by: Wenbin Mei <wenbin.mei@mediatek.com>
Cc: stable@vger.kernel.org
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Fixes: a4080225f5 ("mmc: cqhci: support for command queue enabled host")
Link: https://lore.kernel.org/r/20211026070812.9359-1-wenbin.mei@mediatek.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8a38a4d51c upstream.
The memory at the end of the controller only accepts 32bit read/write
accesses, but the arm64 memcpy_to/fromio implementation only uses 64bit
(which will be split into two 32bit access) and 8bit leading to incomplete
copies to/from this memory when the buffer is not multiple of 8bytes.
Add a local copy using writel/readl accesses to make sure we use the right
memory access width.
The switch to memcpy_to/fromio was done because of 285133040e
("arm64: Import latest memcpy()/memmove() implementation"), but using memcpy
worked before since it mainly used 32bit memory acceses.
Fixes: 103a5348c2 ("mmc: meson-gx: use memcpy_to/fromio for dram-access-quirk")
Reported-by: Christian Hewitt <christianshewitt@gmail.com>
Suggested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210928073652.434690-1-narmstrong@baylibre.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit e72a55f2e5 ]
When a read/write command is sent via ioctl to the kernel,
and the command fails, the actual error response of the emmc
is not sent to the user.
IOCTL read/write tests are carried out using commands
17 (Single BLock Read), 24 (Single Block Write),
18 (Multi Block Read), 25 (Multi Block Write)
The tests are carried out on a 64Gb emmc device. All of these
tests try to access an "out of range" sector address (0x09B2FFFF).
It is seen that without the patch the response received by the user
is not OUT_OF_RANGE error (R1 response 31st bit is not set) as per
JEDEC specification. After applying the patch proper response is seen.
This is because the function returns without copying the response to
the user in case of failure. This patch fixes the issue.
Hence, this memcpy is required whether we get an error response or not.
Therefor it is moved up from the current position up to immediately
after we have called mmc_wait_for_req().
The test code and the output of only the CMD17 is included in the
commit to limit the message length.
CMD17 (Test Code Snippet):
==========================
printf("Forming CMD%d\n", opt_idx);
/* single block read */
cmd.blksz = 512;
cmd.blocks = 1;
cmd.write_flag = 0;
cmd.opcode = 17;
//cmd.arg = atoi(argv[3]);
cmd.arg = 0x09B2FFFF;
/* Expecting response R1B */
cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
memset(data, 0, sizeof(__u8) * 512);
mmc_ioc_cmd_set_data(cmd, data);
printf("Sending CMD%d: ARG[0x%08x]\n", opt_idx, cmd.arg);
if(ioctl(fd, MMC_IOC_CMD, &cmd))
perror("Error");
printf("\nResponse: %08x\n", cmd.response[0]);
CMD17 (Output without patch):
=============================
test@test-LIVA-Z:~$ sudo ./mmc cmd_test /dev/mmcblk0 17
Entering the do_mmc_commands:Device: /dev/mmcblk0 nargs:4
Entering the do_mmc_commands:Device: /dev/mmcblk0 options[17, 0x09B2FFF]
Forming CMD17
Sending CMD17: ARG[0x09b2ffff]
Error: Connection timed out
Response: 00000000
(Incorrect response)
CMD17 (Output with patch):
==========================
test@test-LIVA-Z:~$ sudo ./mmc cmd_test /dev/mmcblk0 17
[sudo] password for test:
Entering the do_mmc_commands:Device: /dev/mmcblk0 nargs:4
Entering the do_mmc_commands:Device: /dev/mmcblk0 options[17, 09B2FFFF]
Forming CMD17
Sending CMD17: ARG[0x09b2ffff]
Error: Connection timed out
Response: 80000900
(Correct OUT_OF_ERROR response as per JEDEC specification)
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20210824191726.8296-1-nishadkamdar@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3ac5e45291 ]
For unexplained reasons, the prescaler register for this device needs to
be cleared (set to 1) while performing a data read or else the command
will hang. This does not appear to affect the real clock rate sent out
on the bus, so I assume it's purely to work around a hardware bug.
During normal operation, the prescaler is already set to 1, so nothing
needs to be done. However, in "initial mode" (which is used for sub-MHz
clock speeds, like the core sets while enumerating cards), it's set to
128 and so we need to reset it during data reads. We currently fail to
do this for long reads.
This has no functional affect on the driver's operation currently
written, as the MMC core always sets a clock above 1MHz before
attempting any long reads. However, the core could conceivably set any
clock speed at any time and the driver should still work, so I think
this fix is worthwhile.
I personally encountered this issue while performing data recovery on an
external chip. My connections had poor signal integrity, so I modified
the core code to reduce the clock speed. Without this change, I saw the
card enumerate but was unable to actually read any data.
Writes don't seem to work in the situation described above even with
this change (and even if the workaround is extended to encompass data
write commands). I was not able to find a way to get them working.
Signed-off-by: Thomas Hebb <tommyhebb@gmail.com>
Link: https://lore.kernel.org/r/2fef280d8409ab0100c26c6ac7050227defd098d.1627818365.git.tommyhebb@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 885814a97f ]
This reverts commit 419dd626e3.
It turned out that the change from the reverted commit breaks the ACPI
based rpi's because it causes the 100Mhz max clock to be overridden to the
return from sdhci_iproc_get_max_clock(), which is 0 because there isn't a
OF/DT based clock device.
Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Fixes: 419dd626e3 ("mmc: sdhci-iproc: Set SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN on BCM2711")
Acked-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
