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git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These clean up and rework the PM QoS API, address a suspend-to-idle
wakeup regression on some ACPI-based platforms, clean up and extend a
few cpuidle drivers, update multiple cpufreq drivers and cpufreq
documentation, and fix a number of issues in devfreq and several other
things all over.
Specifics:
- Clean up and rework the PM QoS API to simplify the code and reduce
the size of it (Rafael Wysocki).
- Fix a suspend-to-idle wakeup regression on Dell XPS13 9370 and
similar platforms where the USB plug/unplug events are handled by
the EC (Rafael Wysocki).
- CLean up the intel_idle and PSCI cpuidle drivers (Rafael Wysocki,
Ulf Hansson).
- Extend the haltpoll cpuidle driver so that it can be forced to run
on some systems where it refused to load (Maciej Szmigiero).
- Convert several cpufreq documents to the .rst format and move the
legacy driver documentation into one common file (Mauro Carvalho
Chehab, Rafael Wysocki).
- Update several cpufreq drivers:
* Extend and fix the imx-cpufreq-dt driver (Anson Huang).
* Improve the -EPROBE_DEFER handling and fix unwanted CPU
overclocking on i.MX6ULL in imx6q-cpufreq (Anson Huang,
Christoph Niedermaier).
* Add support for Krait based SoCs to the qcom driver (Ansuel
Smith).
* Add support for OPP_PLUS to ti-cpufreq (Lokesh Vutla).
* Add platform specific intermediate callbacks support to
cpufreq-dt and update the imx6q driver (Peng Fan).
* Simplify and consolidate some pieces of the intel_pstate
driver and update its documentation (Rafael Wysocki, Alex
Hung).
- Fix several devfreq issues:
* Remove unneeded extern keyword from a devfreq header file and
use the DEVFREQ_GOV_UPDATE_INTERNAL event name instead of
DEVFREQ_GOV_INTERNAL (Chanwoo Choi).
* Fix the handling of dev_pm_qos_remove_request() result
(Leonard Crestez).
* Use constant name for userspace governor (Pierre Kuo).
* Get rid of doc warnings and fix a typo (Christophe JAILLET).
- Use built-in RCU list checking in some places in the PM core to
avoid false-positive RCU usage warnings (Madhuparna Bhowmik).
- Add explicit READ_ONCE()/WRITE_ONCE() annotations to low-level PM
QoS routines (Qian Cai).
- Fix removal of wakeup sources to avoid NULL pointer dereferences in
a corner case (Neeraj Upadhyay).
- Clean up the handling of hibernate compat ioctls and fix the
related documentation (Eric Biggers).
- Update the idle_inject power capping driver to use variable-length
arrays instead of zero-length arrays (Gustavo Silva).
- Fix list format in a PM QoS document (Randy Dunlap).
- Make the cpufreq stats module use scnprintf() to avoid potential
buffer overflows (Takashi Iwai).
- Add pm_runtime_get_if_active() to PM-runtime API (Sakari Ailus).
- Allow no domain-idle-states DT property in generic PM domains (Ulf
Hansson).
- Fix a broken y-axis scale in the intel_pstate_tracer utility (Doug
Smythies)"
* tag 'pm-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (78 commits)
cpufreq: intel_pstate: Simplify intel_pstate_cpu_init()
tools/power/x86/intel_pstate_tracer: fix a broken y-axis scale
ACPI: PM: s2idle: Refine active GPEs check
ACPICA: Allow acpi_any_gpe_status_set() to skip one GPE
PM: sleep: wakeup: Skip wakeup_source_sysfs_remove() if device is not there
PM / devfreq: Get rid of some doc warnings
PM / devfreq: Fix handling dev_pm_qos_remove_request result
PM / devfreq: Fix a typo in a comment
PM / devfreq: Change to DEVFREQ_GOV_UPDATE_INTERVAL event name
PM / devfreq: Remove unneeded extern keyword
PM / devfreq: Use constant name of userspace governor
ACPI: PM: s2idle: Fix comment in acpi_s2idle_prepare_late()
cpufreq: qcom: Add support for krait based socs
cpufreq: imx6q-cpufreq: Improve the logic of -EPROBE_DEFER handling
cpufreq: Use scnprintf() for avoiding potential buffer overflow
cpuidle: psci: Split psci_dt_cpu_init_idle()
PM / Domains: Allow no domain-idle-states DT property in genpd when parsing
PM / hibernate: Remove unnecessary compat ioctl overrides
PM: hibernate: fix docs for ioctls that return loff_t via pointer
Documentation: intel_pstate: update links for references
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* pm-qos: (30 commits)
PM: QoS: annotate data races in pm_qos_*_value()
Documentation: power: fix pm_qos_interface.rst format warning
PM: QoS: Make CPU latency QoS depend on CONFIG_CPU_IDLE
Documentation: PM: QoS: Update to reflect previous code changes
PM: QoS: Update file information comments
PM: QoS: Drop PM_QOS_CPU_DMA_LATENCY and rename related functions
sound: Call cpu_latency_qos_*() instead of pm_qos_*()
drivers: usb: Call cpu_latency_qos_*() instead of pm_qos_*()
drivers: tty: Call cpu_latency_qos_*() instead of pm_qos_*()
drivers: spi: Call cpu_latency_qos_*() instead of pm_qos_*()
drivers: net: Call cpu_latency_qos_*() instead of pm_qos_*()
drivers: mmc: Call cpu_latency_qos_*() instead of pm_qos_*()
drivers: media: Call cpu_latency_qos_*() instead of pm_qos_*()
drivers: hsi: Call cpu_latency_qos_*() instead of pm_qos_*()
drm: i915: Call cpu_latency_qos_*() instead of pm_qos_*()
x86: platform: iosf_mbi: Call cpu_latency_qos_*() instead of pm_qos_*()
cpuidle: Call cpu_latency_qos_limit() instead of pm_qos_request()
PM: QoS: Add CPU latency QoS API wrappers
PM: QoS: Adjust pm_qos_request() signature and reorder pm_qos.h
PM: QoS: Simplify definitions of CPU latency QoS trace events
...
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This switches the EFM32 driver over to use the GPIO descriptor
handling in the core. The GPIO handling in this driver is
pretty simplistic so this should just work. Drop the GPIO headers
and insert the implicitly included <linux/of.h> header.
Signed-off-by: Linus Walleij <linus.walleij-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Cc: Uwe Kleine-König <u.kleine-koenig-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
Link: https://lore.kernel.org/r/20200317094914.331932-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
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The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Link: https://lore.kernel.org/r/20200320232515.GA24800@embeddedor.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Andi Shyti <andi@etezian.org>
Link: https://lore.kernel.org/r/20200320232556.GA24989@embeddedor.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Fix all functions and structure descriptions to have the driver
warning free when built with W=1.
Signed-off-by: Alain Volmat <alain.volmat@st.com>
Reviewed-by: Amelie Delaunay <amelie.delaunay@st.com>
Link: https://lore.kernel.org/r/1584711857-9162-1-git-send-email-alain.volmat@st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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This feature should not be enabled in release but can be useful for
developers who need to monitor register accesses at some specific places.
Helped me identify a bug in u-boot, by comparing the register accesses
from the linux driver with the ones from its u-boot variant.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20200320065058.891221-1-tudor.ambarus@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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This is similar to the DSPI instantiation on LS1028A, except that:
- The A-011218 erratum has been fixed, so DMA works
- The endianness is different, which has implications on XSPI mode
Some benchmarking with the following command:
spidev_test --device /dev/spidev2.0 --bpw 8 --size 256 --cpha --iter 10000000 --speed 20000000
shows that in DMA mode, it can achieve around 2400 kbps, and in XSPI
mode, the same command goes up to 4700 kbps. This is somewhat to be
expected, since the DMA buffer size is extremely small at 8 bytes, the
winner becomes whomever can prepare the buffers for transmission
quicker, and DMA mode has higher overhead there. So XSPI FIFO mode has
been chosen as the operating mode for this chip.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200318001603.9650-11-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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The operating mode (DMA, XSPI, EOQ) is not going to change across the
lifetime of the device. So it makes no sense to keep writing to SPI_RSER
on each message. Move this configuration to dspi_init instead.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200318001603.9650-10-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Interrupts are not necessary for DMA functionality, since the completion
event is provided by the DMA driver.
But if the driver fails to request the IRQ defined in the device tree,
it will call dspi_poll which would make the driver hang waiting for data
to become available in the RX FIFO.
Fixes: c55be3059159 ("spi: spi-fsl-dspi: Use poll mode in case the platform IRQ is missing")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200318001603.9650-9-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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The driver does not create the dspi->dma structure unless operating in
DSPI_DMA_MODE, so it makes sense to check for that.
Fixes: f4b323905d8b ("spi: Introduce dspi_slave_abort() function for NXP's dspi SPI driver")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200318001603.9650-8-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Currently the driver puts the process in interruptible sleep waiting for
the interrupt train to finish transfer to/from the tx_buf and rx_buf.
But exiting the process with ctrl-c may make the kernel panic: the
wait_event_interruptible call will return -ERESTARTSYS, which a proper
driver implementation is perhaps supposed to handle, but nonetheless
this one doesn't, and aborts the transfer altogether.
Actually when the task is interrupted, there is still a high chance that
the dspi_interrupt is still triggering. And if dspi_transfer_one_message
returns execution all the way to the spi_device driver, that can free
the spi_message and spi_transfer structures, leaving the interrupts to
access a freed tx_buf and rx_buf.
hexdump -C /dev/mtd0
00000000 00 75 68 75 0a ff ff ff ff ff ff ff ff ff ff ff
|.uhu............|
00000010 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
|................|
*
^C[ 38.495955] fsl-dspi 2120000.spi: Waiting for transfer to complete failed!
[ 38.503097] spi_master spi2: failed to transfer one message from queue
[ 38.509729] Unable to handle kernel paging request at virtual address ffff800095ab3377
[ 38.517676] Mem abort info:
[ 38.520474] ESR = 0x96000045
[ 38.523533] EC = 0x25: DABT (current EL), IL = 32 bits
[ 38.528861] SET = 0, FnV = 0
[ 38.531921] EA = 0, S1PTW = 0
[ 38.535067] Data abort info:
[ 38.537952] ISV = 0, ISS = 0x00000045
[ 38.541797] CM = 0, WnR = 1
[ 38.544771] swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000082621000
[ 38.551494] [ffff800095ab3377] pgd=00000020fffff003, p4d=00000020fffff003, pud=0000000000000000
[ 38.560229] Internal error: Oops: 96000045 [#1] PREEMPT SMP
[ 38.565819] Modules linked in:
[ 38.568882] CPU: 0 PID: 2729 Comm: hexdump Not tainted 5.6.0-rc4-next-20200306-00052-gd8730cdc8a0b-dirty #193
[ 38.578834] Hardware name: Kontron SMARC-sAL28 (Single PHY) on SMARC Eval 2.0 carrier (DT)
[ 38.587129] pstate: 20000085 (nzCv daIf -PAN -UAO)
[ 38.591941] pc : ktime_get_real_ts64+0x3c/0x110
[ 38.596487] lr : spi_take_timestamp_pre+0x40/0x90
[ 38.601203] sp : ffff800010003d90
[ 38.604525] x29: ffff800010003d90 x28: ffff80001200e000
[ 38.609854] x27: ffff800011da9000 x26: ffff002079c40400
[ 38.615184] x25: ffff8000117fe018 x24: ffff800011daa1a0
[ 38.620513] x23: ffff800015ab3860 x22: ffff800095ab3377
[ 38.625841] x21: 000000000000146e x20: ffff8000120c3000
[ 38.631170] x19: ffff0020795f6e80 x18: ffff800011da9948
[ 38.636498] x17: 0000000000000000 x16: 0000000000000000
[ 38.641826] x15: ffff800095ab3377 x14: 0720072007200720
[ 38.647155] x13: 0720072007200765 x12: 0775076507750771
[ 38.652483] x11: 0720076d076f0772 x10: 0000000000000040
[ 38.657812] x9 : ffff8000108e2100 x8 : ffff800011dcabe8
[ 38.663139] x7 : 0000000000000000 x6 : ffff800015ab3a60
[ 38.668468] x5 : 0000000007200720 x4 : ffff800095ab3377
[ 38.673796] x3 : 0000000000000000 x2 : 0000000000000ab0
[ 38.679125] x1 : ffff800011daa000 x0 : 0000000000000026
[ 38.684454] Call trace:
[ 38.686905] ktime_get_real_ts64+0x3c/0x110
[ 38.691100] spi_take_timestamp_pre+0x40/0x90
[ 38.695470] dspi_fifo_write+0x58/0x2c0
[ 38.699315] dspi_interrupt+0xbc/0xd0
[ 38.702987] __handle_irq_event_percpu+0x78/0x2c0
[ 38.707706] handle_irq_event_percpu+0x3c/0x90
[ 38.712161] handle_irq_event+0x4c/0xd0
[ 38.716008] handle_fasteoi_irq+0xbc/0x170
[ 38.720115] generic_handle_irq+0x2c/0x40
[ 38.724135] __handle_domain_irq+0x68/0xc0
[ 38.728243] gic_handle_irq+0xc8/0x160
[ 38.732000] el1_irq+0xb8/0x180
[ 38.735149] spi_nor_spimem_read_data+0xe0/0x140
[ 38.739779] spi_nor_read+0xc4/0x120
[ 38.743364] mtd_read_oob+0xa8/0xc0
[ 38.746860] mtd_read+0x4c/0x80
[ 38.750007] mtdchar_read+0x108/0x2a0
[ 38.753679] __vfs_read+0x20/0x50
[ 38.757002] vfs_read+0xa4/0x190
[ 38.760237] ksys_read+0x6c/0xf0
[ 38.763471] __arm64_sys_read+0x20/0x30
[ 38.767319] el0_svc_common.constprop.3+0x90/0x160
[ 38.772125] do_el0_svc+0x28/0x90
[ 38.775449] el0_sync_handler+0x118/0x190
[ 38.779468] el0_sync+0x140/0x180
[ 38.782793] Code: 91000294 1400000f d50339bf f9405e80 (f90002c0)
[ 38.788910] ---[ end trace 55da560db4d6bef7 ]---
[ 38.793540] Kernel panic - not syncing: Fatal exception in interrupt
[ 38.799914] SMP: stopping secondary CPUs
[ 38.803849] Kernel Offset: disabled
[ 38.807344] CPU features: 0x10002,20006008
[ 38.811451] Memory Limit: none
[ 38.814513] ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---
So it is clear that the "interruptible" part isn't handled correctly.
When the process receives a signal, one could either attempt a clean
abort (which appears to be difficult with this hardware) or just keep
restarting the sleep until the wait queue really completes. But checking
in a loop for -ERESTARTSYS is a bit too complicated for this driver, so
just make the sleep uninterruptible, to avoid all that nonsense.
The wait queue was actually restructured as a completion, after polling
other drivers for the most "popular" approach.
Fixes: 349ad66c0ab0 ("spi:Add Freescale DSPI driver for Vybrid VF610 platform")
Reported-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200318001603.9650-7-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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dspi->words_in_flight is a variable populated in the *_write functions
and used in the dspi_fifo_read function. It is also used in
dspi_fifo_write, immediately after transmission, to update the
message->actual_length variable used by higher layers such as spi-mem
for integrity checking.
But it may happen that the IRQ which calls dspi_fifo_read to be
triggered before the updating of message->actual_length takes place. In
that case, dspi_fifo_read will decrement dspi->words_in_flight to -1,
and that will cause an invalid modification of message->actual_length.
For that, we make the simplest fix possible: to not decrement the actual
shared variable in dspi->words_in_flight from dspi_fifo_read, but
actually a copy of it which is on stack.
But even if dspi_fifo_read from the next IRQ does not interfere with the
dspi_fifo_write of the current chunk, the *next* dspi_fifo_write still
can. So we must assume that everything after the last write to the TX
FIFO can be preempted by the "TX complete" IRQ, and the dspi_fifo_write
function must be safe against that. This means refactoring the 2
flavours of FIFO writes (for EOQ and XSPI) such that the calculation of
the number of words to be written is common and happens a priori. This
way, the code for updating the message->actual_length variable works
with a copy and not with the volatile dspi->words_in_flight.
After some interior debate, the dspi->progress variable used for
software timestamping was *not* backed up against preemption in a copy
on stack. Because if preemption does occur between
spi_take_timestamp_pre and spi_take_timestamp_post, there's really no
point in trying to save anything. The first-in-time
spi_take_timestamp_post call with a dspi->progress higher than the
requested xfer->ptp_sts_word_post will trigger xfer->timestamped = true
anyway and will close the deal.
To understand the above a bit better, consider a transfer with
xfer->ptp_sts_word_pre = xfer->ptp_sts_word_post = 3, and
xfer->bits_per_words = 8 (so byte 3 needs to be timestamped). The DSPI
controller timestamps in chunks of 4 bytes at a time, and preemption
occurs in the middle of timestamping the first chunk:
spi_take_timestamp_pre(0)
.
. (preemption)
.
. spi_take_timestamp_pre(4)
.
. spi_take_timestamp_post(7)
.
spi_take_timestamp_post(3)
So the reason I'm not bothering to back up dspi->progress for that
spi_take_timestamp_post(3) is that spi_take_timestamp_post(7) is going
to (a) be more honest, (b) provide better accuracy and (c) already
render the spi_take_timestamp_post(3) into a noop by setting
xfer->timestamped = true anyway.
Fixes: d59c90a2400f ("spi: spi-fsl-dspi: Convert TCFQ users to XSPI FIFO mode")
Reported-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200318001603.9650-6-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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If dspi->words_in_flight is populated with the hardware FIFO size,
then in dspi_fifo_read it will attempt to read more data at the end of a
buffer that is not a multiple of 16 bytes in length. It will probably
time out attempting to do so.
So limit the num_fifo_entries variable to the actual number of FIFO
entries that is going to be used.
Fixes: d59c90a2400f ("spi: spi-fsl-dspi: Convert TCFQ users to XSPI FIFO mode")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200318001603.9650-5-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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In DMA mode, dspi_setup_accel does not get called, which results in the
dspi->oper_word_size variable (which is used by dspi_dma_xfer) to not be
initialized properly.
Because oper_word_size is zero, a few calculations end up being
incorrect, and the DMA transfer eventually times out instead of sending
anything on the wire.
Set up native transfers (or 8-on-16 acceleration) using dspi_setup_accel
for DMA mode too.
Also take the opportunity and simplify the DMA buffer handling a little
bit.
Fixes: 6c1c26ecd9a3 ("spi: spi-fsl-dspi: Accelerate transfers using larger word size if possible")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200318001603.9650-4-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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In XSPI mode, the 32-bit PUSHR register can be written to separately:
the higher 16 bits are for commands and the lower 16 bits are for data.
This has nicely been hacked around, by defining a second regmap with a
width of 16 bits, and effectively splitting a 32-bit register into 2
16-bit ones, from the perspective of this regmap_pushr.
The problem is the assumption about the controller's endianness. If the
controller is little endian (such as anything post-LS1046A), then the
first 2 bytes, in the order imposed by memory layout, will actually hold
the TXDATA, and the last 2 bytes will hold the CMD.
So take the controller's endianness into account when performing split
writes to PUSHR. The obvious and simple solution would have been to call
regmap_get_val_endian(), but that is an internal regmap function and we
don't want to change regmap just for this. Therefore, we just re-read
the "big-endian" device tree property.
Fixes: 58ba07ec79e6 ("spi: spi-fsl-dspi: Add support for XSPI mode registers")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200318001603.9650-3-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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The SPI_MCR_PCSIS macro assumes that the controller has a number of chip
select signals equal to 6. That is not always the case, but actually is
described through the driver-specific "spi-num-chipselects" device tree
binding. LS1028A for example only has 4 chip selects.
Don't write to the upper bits of the PCSIS field, which are reserved in
the reference manual.
Fixes: 349ad66c0ab0 ("spi:Add Freescale DSPI driver for Vybrid VF610 platform")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200318001603.9650-2-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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This driver is not using any symbols from the GPIO .h files
so drop them.
It was however implicitly using <linux/pinctrl/consumer.h>
so include that instead.
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200317092457.264055-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
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Neil Armstrong <narmstrong@baylibre.com>:
The SPICC controller in Amlogic AXG & G12A is capable of driving the
CLK/MOSI/SS signal lines through the idle state which avoid the signals
floating in unexpected state, is capable of using linear clock divider
to reach a much fine tuned range of clocks, while the old controller only
uses a power of two clock divider, result at a more coarse clock range and
finally is capable of running at 80M clock.
The SPICC controller in Amlogic G12A takes the source clock from a specific
clock instead of the bus clock and has a different FIFO size and doesn't
handle the RX Half interrupt the same way as GXL & AXG variants. Thus
the burst management is simplified and takes in account a variable FIFO
size.
Now the controller can support frequencies higher than 30MHz, we need
the setup the I/O line delays in regard of the SPI clock frequency.
Neil Armstrong (7):
spi: meson-spicc: remove unused variables
spi: meson-spicc: support max 80MHz clock
spi: meson-spicc: add min sclk for each compatible
spi: meson-spicc: setup IO line delay
spi: meson-spicc: adapt burst handling for G12A support
dt-bindings: spi: amlogic,meson-gx-spicc: add Amlogic G12A compatible
spi: meson-spicc: add support for Amlogic G12A
Sunny Luo (2):
spi: meson-spicc: enhance output enable feature
spi: meson-spicc: add a linear clock divider support
.../bindings/spi/amlogic,meson-gx-spicc.yaml | 22 +
drivers/spi/Kconfig | 1 +
drivers/spi/spi-meson-spicc.c | 496 +++++++++++++-----
3 files changed, 392 insertions(+), 127 deletions(-)
--
2.22.0
_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic
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to_spi_device() already checks 'dev'. No need to do it before calling
it.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://lore.kernel.org/r/20200312134507.10000-1-wsa@the-dreams.de
Signed-off-by: Mark Brown <broonie@kernel.org>
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Add support for the SPICC controllers on the Amlogic G12A SoCs family.
The G12A SPICC controllers inherit from the AXG enhanced registers but
takes an external pclk for the baud rate generator and can achieve up to
166MHz SCLK.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20200312133131.26430-10-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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The G12A SPICC controller variant has a different FIFO size and doesn't
handle the RX Half interrupt the same way as GXL & AXG variants.
Thus simplify the burst management and take in account a variable FIFO
size.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20200312133131.26430-8-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Now the controller can support frequencies higher than 30MHz, we need
the setup the I/O line delays in regard of the SPI clock frequency.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20200312133131.26430-7-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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The G12A SPICC controller variant takes the source clock from a specific
clock instead of the bus clock.
The minimal clock calculus won't work with the G12A support, thus add the
minimal supported clock for each variant and pass this to the SPI core.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20200312133131.26430-6-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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The SPICC controller in Meson-AXG is capable of running at 80M clock.
The ASIC IP is improved and the clock is actually running higher than
previous old SoCs.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Sunny Luo <sunny.luo@amlogic.com>
Link: https://lore.kernel.org/r/20200312133131.26430-5-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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The SPICC controller in Meson-AXG SoC is capable of using
a linear clock divider to reach a much fine tuned range of clocks,
while the old controller only use a power of two clock divider,
result at a more coarse clock range.
Also convert the clock registration into Common Clock Framework.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Sunny Luo <sunny.luo@amlogic.com>
Link: https://lore.kernel.org/r/20200312133131.26430-4-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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The SPICC controller in Meson-AXG is capable of driving the CLK/MOSI/SS
signal lines through the idle state (between two transmission operation),
which avoid the signals floating in unexpected state.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Sunny Luo <sunny.luo@amlogic.com>
Link: https://lore.kernel.org/r/20200312133131.26430-3-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Remove unused variables from spicc data struct.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20200312133131.26430-2-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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The platform_get_resource_byname() function returns NULL on error, it
doesn't return error pointers.
Fixes: d166a73503ef ("spi: fspi: dynamically alloc AHB memory")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200312113154.GC20562@mwanda
Signed-off-by: Mark Brown <broonie@kernel.org>
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https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-5.7
spi: Rewrite mtk-quadspi spi-nor driver with spi-mem
This patchset from Chuanhong Guo <gch981213@gmail.com> adds a spi-mem
driver for Mediatek SPI-NOR controller, which already has limited
support by mtk-quadspi. This new driver can make use of full quadspi
capability of this controller.
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This is a driver for mtk spi-nor controller using spi-mem interface.
The same controller already has limited support provided by mtk-quadspi
driver under spi-nor framework and this new driver is a replacement
for the old one.
Comparing to the old driver, this driver has following advantages:
1. It can handle any full-duplex spi transfer up to 6 bytes, and
this is implemented using generic spi interface.
2. It take account into command opcode properly. The reading routine
in this controller can only use 0x03 or 0x0b as opcode on 1-1-1
transfers, but old driver doesn't implement this properly. This
driver checks supported opcode explicitly and use (1) to perform
unmatched operations.
3. It properly handles SFDP reading. Old driver can't read SFDP
due to the bug mentioned in (2).
4. It can do 1-2-2 and 1-4-4 fast reading on spi-nor. These two ops
requires parsing SFDP, which isn't possible in old driver. And
the old driver is only flagged to support 1-1-2 mode.
5. It takes advantage of the DMA feature in this controller for
long reads and supports IRQ on DMA requests to free cpu cycles
from polling status registers on long DMA reading. It achieves
up to 17.5MB/s reading speed (1-4-4 mode) which is way faster
than the old one. IRQ is implemented as optional to maintain
backward compatibility.
Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
Link: https://lore.kernel.org/r/20200306085052.28258-3-gch981213@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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We only need a spi-max-frequency when we specifically request a
spi frequency lower than the max speed of spi host.
This property is already documented as optional property and current
host drivers are implemented to operate at highest speed possible
when spi->max_speed_hz is 0.
This patch makes spi-max-frequency an optional property so that
we could just omit it to use max controller speed.
Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
Link: https://lore.kernel.org/r/20200306085052.28258-2-gch981213@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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By selecting MTD_SPI_NOR for SPI_HISI_SFC_V3XX, we may introduce unmet
dependencies:
WARNING: unmet direct dependencies detected for MTD_SPI_NOR
Depends on [m]: MTD [=m] && SPI_MASTER [=y]
Selected by [y]:
- SPI_HISI_SFC_V3XX [=y] && SPI [=y] && SPI_MASTER [=y] && (ARM64 && ACPI [=y] || COMPILE_TEST [=y]) && HAS_IOMEM [=y]
Since MTD_SPI_NOR is only selected by SPI_HISI_SFC_V3XX for practical
reasons - slave devices use the spi-nor driver, enabled by MTD_SPI_NOR -
just drop it.
Signed-off-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1583948115-239907-1-git-send-email-john.garry@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Use the correct device to request the DMA mapping. Otherwise the IOMMU
doesn't get the mapping and it will generate a page fault.
The error messages look like:
[ 3.008452] arm-smmu 5000000.iommu: Unhandled context fault: fsr=0x402, iova=0xf9800000, fsynr=0x3f0022, cbfrsynra=0x828, cb=8
[ 3.020123] arm-smmu 5000000.iommu: Unhandled context fault: fsr=0x402, iova=0xf9800000, fsynr=0x3f0022, cbfrsynra=0x828, cb=8
This was tested on a custom board with a LS1028A SoC.
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200310073313.21277-1-michael@walle.cc
Signed-off-by: Mark Brown <broonie@kernel.org>
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<eajames@linux.ibm.com>:
This series adds a dts binding and a driver for a new SPI controller that is
accessed over FSI bus.
Eddie James (2):
dt-bindings: fsi: Add FSI2SPI bindings
spi: Add FSI-attached SPI controller driver
.../devicetree/bindings/fsi/ibm,fsi2spi.yaml | 36 ++
MAINTAINERS | 7 +
drivers/spi/Kconfig | 7 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-fsi.c | 558 ++++++++++++++++++
5 files changed, 609 insertions(+)
create mode 100644 Documentation/devicetree/bindings/fsi/ibm,fsi2spi.yaml
create mode 100644 drivers/spi/spi-fsi.c
--
2.24.0
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All RSPI variants support setting the polarity of the SSL signal.
Advertize support for active-high chip selects, and configure polarity
according to the state of the flag.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200309171537.21551-1-geert+renesas@glider.be
Signed-off-by: Mark Brown <broonie@kernel.org>
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The Rockchip spi binding is updated to yaml and new models
were added. The spi on px30,rk3308 and rk3328 are the same as
other Rockchip based SoCs, so add compatible string for it.
Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Link: https://lore.kernel.org/r/20200309151004.7780-1-jbx6244@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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There exists a set of SPI controllers on some POWER processors that may
be accessed through the FSI bus. Add a driver to traverse the FSI CFAM
engine that can access and drive the SPI controllers. This driver would
typically be used by a baseboard management controller (BMC).
The SPI controllers operate by means of programming a sequencing engine
which automatically manages the usual SPI protocol buses. The driver
programs each transfer into the sequencer as various operations
specifying the slave chip and shifting data in and out on the lines.
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20200306194118.18581-3-eajames@linux.ibm.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi fixes from Mark Brown:
"A selection of small fixes, mostly for drivers, that have arrived
since the merge window. None of them are earth shattering in
themselves but all useful for affected systems"
* tag 'spi-fix-v5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: spi_register_controller(): free bus id on error paths
spi: bcm63xx-hsspi: Really keep pll clk enabled
spi: atmel-quadspi: fix possible MMIO window size overrun
spi/zynqmp: remove entry that causes a cs glitch
spi: pxa2xx: Add CS control clock quirk
spi: spidev: Fix CS polarity if GPIO descriptors are used
spi: qup: call spi_qup_pm_resume_runtime before suspending
spi: spi-omap2-mcspi: Support probe deferral for DMA channels
spi: spi-omap2-mcspi: Handle DMA size restriction on AM65x
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commit a2ca53b52e00 ("spi: Add HiSilicon v3xx SPI NOR flash
controller driver") likely inadvertently used a select statement
with a CONFIG_ prefix, remove the prefix.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/f8ac6b32a29b9a05b58a7e58ffe8b780642abbf1.camel@perches.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Oltean <olteanv@gmail.com>
Vladimir Oltean <vladimir.oltean@nxp.com>:
From: Vladimir Oltean <vladimir.oltean@nxp.com>
This series aims to remove the most inefficient transfer method from the
NXP DSPI driver.
TCFQ (Transfer Complete Flag) mode works by transferring one word,
waiting for its TX confirmation interrupt (or polling on the equivalent
status bit), sending the next word, etc, until the buffer is complete.
The issue with this mode is that it's fundamentally incompatible with
any sort of batching such as writing to a FIFO. But actually, due to
previous patchset ("Compatible string consolidation for NXP DSPI driver"):
https://patchwork.kernel.org/cover/11414593/
all existing users of TCFQ mode today already support a more advanced
feature set, in the form of XSPI (extended SPI). XSPI brings 2 extra
features:
- Word sizes up to 32 bits. This is sub-utilized today, and acceleration
of smaller-than-32 bpw values is provided.
- "Command cycling", basically the ability to write multiple words in a
row and receiving an interrupt only after the completion of the last
one. This is what enables us to make use of the full FIFO depth of
this controller.
Series was tested on the NXP LS1021A-TSN and LS1043A-RDB boards, both
functionally as well as from a performance standpoint.
The command used to benchmark the increased throughput was:
spidev_test --device /dev/spidev1.0 --bpw 8 --size 256 --cpha --iter 10000000 --speed 20000000
where spidev1.0 is a dummy spidev node, using a chip select that no
peripheral responds to.
On LS1021A, which has a 4-entry-deep FIFO and a less powerful CPU, the
performance increase brought by this patchset is from 2700 kbps to 5800
kbps.
On LS1043A, which has a 16-entry-deep FIFO and a more powerful CPU, the
performance increases from 4100 kbps to 13700 kbps.
On average, SPI software timestamping is not adversely affected by the
extra batching, due to the extra patches.
There is one extra patch which clarifies why the TCFQ users were not
converted to the "other" mode in this driver that makes use of the FIFO,
which would be EOQ mode.
My request to the many people on CC (known users and/or contributors) is
to give this series a test to ensure there are no regressions, and for
the Coldfire maintainers to clarify whether the EOQ limitation is
acceptable for them in the long run.
Vladimir Oltean (12):
spi: spi-fsl-dspi: Simplify bytes_per_word gymnastics
spi: spi-fsl-dspi: Remove unused chip->void_write_data
spi: spi-fsl-dspi: Don't mask off undefined bits
spi: spi-fsl-dspi: Add comments around dspi_pop_tx and dspi_push_rx
functions
spi: spi-fsl-dspi: Rename fifo_{read,write} and {tx,cmd}_fifo_write
spi: spi-fsl-dspi: Implement .max_message_size method for EOQ mode
spi: Do spi_take_timestamp_pre for as many times as necessary
spi: spi-fsl-dspi: Convert TCFQ users to XSPI FIFO mode
spi: spi-fsl-dspi: Accelerate transfers using larger word size if
possible
spi: spi-fsl-dspi: Optimize dspi_setup_accel for lowest interrupt
count
spi: spi-fsl-dspi: Use EOQ for last word in buffer even for XSPI mode
spi: spi-fsl-dspi: Take software timestamp in dspi_fifo_write
drivers/spi/spi-fsl-dspi.c | 421 ++++++++++++++++++++++++-------------
drivers/spi/spi.c | 19 +-
include/linux/spi/spi.h | 3 +-
3 files changed, 288 insertions(+), 155 deletions(-)
--
2.17.1
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The SPI bus number is completely optional to Linux, so make the
corresponding device tree property optional as well.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Link: https://lore.kernel.org/r/20200305115546.31814-1-s.hauer@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
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Apply patch from NXP upstream repo to
Enable the octal combination mode in MCR0
Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Han Xu <han.xu@nxp.com>
Link: https://lore.kernel.org/r/20200126140913.2139260-3-aford173@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Apply patch from NXP upstream repo to
dynamically allocate AHB memory as needed.
Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Han Xu <han.xu@nxp.com>
Link: https://lore.kernel.org/r/20200126140913.2139260-2-aford173@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Pull in this patch from NXP's upstream repo to
enable fspi on imx8qxp and imx8mm
Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Han Xu <han.xu@nxp.com>
Link: https://lore.kernel.org/r/20200126140913.2139260-1-aford173@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Although the SPI system timestamps are supposed to reflect the moment
that the peripheral has received a word rather than the moment when the
CPU has enqueued that word to the FIFO, in practice it is easier to just
record the latter time than the former (with a smaller error).
With the recent migration of TCFQ users from poll back to interrupt mode
(this time for XSPI FIFO), it's wiser to keep the interrupt latency
outside of the measurement of the PTP system timestamp itself. If there
proves to be any constant offset that requires static compensation, that
can always be added later. So far that does not appear to be the case at
least on the LS1021A-TSN board, where testing shows that the phc2sys
offset is able to remain within +/- 200 ns even after 68 hours of
testing.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-13-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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The EOQ mode has a hardware limitation in that it stops the transmission
(including the deassertion of the chip select signal) once the host CPU
requests end-of-queue for a particular word in the TX FIFO.
And XSPI mode has a limitation in that we need a separate CMD FIFO entry
for the last byte in the buffer, where the chip select signal needs to
be deasserted. It's not a functional limitation, but it's rather clunky
and the fact that we need to halt the pipeline and write a single entry
to the TX FIFO whenever a buffer ends brings the throughput down when
transmitting small buffers.
So the idea here is to use EOQ's limitation in our favor when using XSPI
mode. Stop special-casing that final word in the buffer, and just kill
the chip select signal by issuing an EOQ for that last word. Now it can
be mixed in with all the other words in the current TX FIFO train.
A small trick here is that we still keep using the XSPI-specific
signaling via the CMDTCFQ interrupt in RSER, and not enabling the EOQ
interrupt, in order to avoid hardware weirdness (potential races with
separate interrupts being raised for CMDTCFQ and EOQ for what is in fact
the end of the same transmission). That is just theoretical, but it's
good to be cautious, and the EOQ interrupt isn't needed.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-12-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
|
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Currently, a SPI transfer that is not multiple of the highest supported
word width (e.g. 4 bytes) will be transmitted as follows (assume a
30-byte buffer transmitted through a 32-bit wide FIFO that is 32 bytes
deep):
- First 28 bytes are sent as 7 words of 32 bits each
- Last 2 bytes are sent as 1 word of 16 bits size
But if the dspi_setup_accel function had decided to use a lower
oper_bits_per_word value (16 instead of 32), there would have been
enough space in the TX FIFO to fit the entire buffer in one go (15 words
of 16 bits each).
What we're actually trying to avoid is mixing word sizes within the same
run with the TX FIFO, since there is an erratum surrounding this, and
invalid data might get transmitted.
So this patch adds special cases for when the remaining length of the
buffer can be sent in one go as 8-bit or 16-bit words, otherwise it
falls back to the standard logic of sending as many bytes as possible at
the highest oper_bits_per_word value possible.
The benefit is that there will be one less CMDFQ/EOQ interrupt to
service when the entire buffer is transmitted during a single go, and
that will improve the overall latency of the transfer.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-11-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
|
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This patch adds logic in the driver to transmit SPI buffers that use
bits_per_word=8 with a higher bits_per_word count (multiple of 8).
Currently the following (most common) modes are implemented:
- 8 bits_per_word on 32-bit capable controllers
- 8 bits_per_word on 16-bit capable controllers
- 16 bits_per_word on 32-bit capable controllers
Transfers which are not accelerated are transferred with a hardware
bits_per_word value equal to the one of the SPI transfer.
The difference from just extending bits_per_word=32 at the spi_device
driver level is that endianness is different - the SPI core wants to
treat bits_per_word=32 buffers as arrays of u32 (i.e. words in host CPU
endianness). So to preserve endianness when clumping 8x4 bits into
32-bit words, one must perform conversion between CPU and standard (big)
endianness.
All appearances (both on the wire as well as in the buffers presented to
the peripheral driver) are preserved, just that accesses to the PUSHR
and POPR registers are now more efficient, since the same number of
reads/writes can now carry more data (2x more data on TX, 4x more data
on RX).
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200304220044.11193-10-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
|
