The interaction with the controller message queue and its corresponding
auxiliary flags and variables requires the use of the queue_lock which is
costly. Since spi_sync will transfer the complete message anyway, and not
return until it is finished, there is no need to put the message into the
queue if the queue is empty. This can save a lot of overhead.
As an example of how significant this is, when using the MCP2518FD SPI CAN
controller on a i.MX8MM SoC, the time during which the interrupt line
stays active (during 3 relatively short spi_sync messages), is reduced
from 98us to 72us by this patch.
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220621061234.3626638-3-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
The topcliff-pch driver requires TX and RX buffers on all transfers, open
coding checks for this. Remove those open coded checks and instead rely on
the core functionality, which has the added bonus that it will fix up any
transfers submitted by drivers as needed rather than erroring out.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220615174138.4060912-1-broonie@kernel.org
Print a warning if the device mode doesn't match the requested mode.
The user doesn't enter the mode in hex so it isn't obvious when
setting the mode succeeds that the mode isn't the requested mode. The
kernel logs a message, it will be more visible if the test also prints
a warning. I was testing --quad, which is unsupported, but doesn't
cause the mode request to fail.
Signed-off-by: David Fries <David@Fries.net>
Link: https://lore.kernel.org/r/YqbNnSGtWHe/GG7w@spacedout.fries.net
Signed-off-by: Mark Brown <broonie@kernel.org>
Merge series from Claudiu Beznea <claudiu.beznea@microchip.com>:
The following series adds runtime PM support for atmel-quadspi driver.
clk_disable()/clk_enable() is called on proper
runtime_suspend()/runtime_resume() ops. Along with it 2 minor cleanups
were added (patches 2/3, 3/3).
On 32 bit systems, the following kernel BUG is hit:
BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
caller is debug_smp_processor_id+0x18/0x24
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.19.0-rc1-00001-g6ae0aec8a366 #181
Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
Backtrace:
dump_backtrace from show_stack+0x20/0x24
r7:81024ffd r6:00000000 r5:81024ffd r4:60000013
show_stack from dump_stack_lvl+0x60/0x78
dump_stack_lvl from dump_stack+0x14/0x1c
r7:81024ffd r6:80f652de r5:80bec180 r4:819a2500
dump_stack from check_preemption_disabled+0xc8/0xf0
check_preemption_disabled from debug_smp_processor_id+0x18/0x24
r8:8119b7e0 r7:81205534 r6:819f5c00 r5:819f4c00 r4:c083d724
debug_smp_processor_id from __spi_sync+0x78/0x220
__spi_sync from spi_sync+0x34/0x4c
r10:bb7bf4e0 r9:c083d724 r8:00000007 r7:81a068c0 r6:822a83c0 r5:c083d724
r4:819f4c00
spi_sync from spi_mem_exec_op+0x338/0x370
r5:000000b4 r4:c083d910
spi_mem_exec_op from spi_nor_read_id+0x98/0xdc
r10:bb7bf4e0 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:82358040
r4:819f7c40
spi_nor_read_id from spi_nor_detect+0x38/0x114
r7:82358040 r6:00000000 r5:819f7c40 r4:819f7c40
spi_nor_detect from spi_nor_scan+0x11c/0xbec
r10:bb7bf4e0 r9:00000000 r8:00000000 r7:c083da4c r6:00000000 r5:00010101
r4:819f7c40
spi_nor_scan from spi_nor_probe+0x10c/0x2d0
r10:bb7bf4e0 r9:bb7bf4d0 r8:00000000 r7:819f4c00 r6:00000000 r5:00000000
r4:819f7c40
per-cpu access needs to be guarded against preemption.
Fixes: 6598b91b5a ("spi: spi.c: Convert statistics to per-cpu u64_stats_t")
Reported-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David Jander <david@protonic.nl>
Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Link: https://lore.kernel.org/r/20220609121334.2984808-1-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
Fixes these "make htmldocs" warnings:
include/linux/spi/spi.h:82: warning: Function parameter or member 'syncp' not described in 'spi_statistics'
include/linux/spi/spi.h:213: warning: Function parameter or member 'pcpu_statistics' not described in 'spi_device'
include/linux/spi/spi.h:676: warning: Function parameter or member 'pcpu_statistics' not described in 'spi_controller'
Fixes: 6598b91b5a ("spi: spi.c: Convert statistics to per-cpu u64_stats_t")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David Jander <david@protonic.nl>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220608153309.2899565-1-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
The spi-ti-qspi driver initializes its spi clock by the
spi-max-frequency property from the controller node, and ignores
per-transfer (and per-slave) speed_hz settings.
Isolate clock settings out from ti_qspi_setup() and call it from
ti_qspi_start_transfer_one() and ti_qspi_exec_mem_op(), using
per-transfer speed_hz and per-slave max_speed_hz settings.
Also drop spi_max_frequency from struct ti_qspi and use spi_master's
max_speed_hz.
Signed-off-by: Atsushi Nemoto <atsushi.nemoto@sord.co.jp>
Link: https://lore.kernel.org/r/20220519.084604.966119051165023533.atsushi.nemoto@sord.co.jp
Signed-off-by: Mark Brown <broonie@kernel.org>
This change gives a dramatic performance improvement in the hot path,
since many costly spin_lock_irqsave() calls can be avoided.
On an i.MX8MM system with a MCP2518FD CAN controller connected via SPI,
the time the driver takes to handle interrupts, or in other words the time
the IRQ line of the CAN controller stays low is mainly dominated by the
time it takes to do 3 relatively short sync SPI transfers. The effect of
this patch is a reduction of this time from 136us down to only 98us.
Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David Jander <david@protonic.nl>
Link: https://lore.kernel.org/r/20220524091808.2269898-1-david@protonic.nl
Signed-off-by: Mark Brown <broonie@kernel.org>
SPI bus per device properties must be defined in spi-peripheral-props.yaml
for unevaluatedProperties checks to work correctly on device nodes.
This has the side effect of promoting 'rx-sample-delay-ns' to be a
common property, but functionally it's no different if it was defined in
a Synopsys specific schema file.
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220525210053.2488756-1-robh@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
ZynqMP GQSPI controller can support up to two chip selects but the current
GQSPI driver only support CS0. With this update and num-cs DT property set
to 2 GQSPI driver can now support two slave devices each connected to one
chip select.
GQSPI driver configures the Lower CS and Upper CS based on the reg DT
property.
Changes tested on ZynqMP board with two SPI-NOR flashes each connected
to a different CS.
Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra@xilinx.com>
Link: https://lore.kernel.org/r/20220512145820.20425-1-amit.kumar-mahapatra@xilinx.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Currently the spi_master is allocated by devm_spi_alloc_master()
and devres core manages the deallocation, but in probe failure
path spi_master_put() is being handled manually which causes
"refcount underflow use-after-free" warning when probe failure happens
after allocating spi_master.
Trimmed backtrace during failure:
refcount_t: underflow; use-after-free.
pc : refcount_warn_saturate+0xf4/0x144
Call trace:
refcount_warn_saturate
kobject_put
put_device
devm_spi_release_controller
devres_release_all
This commit makes relevant changes to remove spi_master_put() from probe
failure path.
Fixes: 606e5d4081 ("spi: cadence-quadspi: Handle spi_unregister_master() in remove()")
Signed-off-by: Vaishnav Achath <vaishnav.a@ti.com>
Link: https://lore.kernel.org/r/20220601071611.11853-1-vaishnav.a@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Current s3c64xx SPI driver acquires DMA channel during driver
probe and holds on it even when channels are not used
(no DMA transfer). This is a problem especially when all the
DMA channels are exhausted (as other IPs on the same DMA
controller also acquires DMA channel) and if a new IP/Device
requests for a DMA channel (on the same DMA controller), it won’t
get DMA channel allocated.
The said issue can be avoided if s3c64xx driver request and
release DMA channel before and after data transfer. Let’s modify
the driver to request and release DMA channel before and after
DMA mode data transfer.
Signed-off-by: Adithya K V <adithya.kv@samsung.com>
Link: https://lore.kernel.org/r/20220524140132.59300-1-adithya.kv@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Pull file descriptor fix from Al Viro:
"Fix for breakage in #work.fd this window"
* tag 'pull-work.fd-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fix the breakage in close_fd_get_file() calling conventions change
Pull mm hotfixes from Andrew Morton:
"Fixups for various recently-added and longer-term issues and a few
minor tweaks:
- fixes for material merged during this merge window
- cc:stable fixes for more longstanding issues
- minor mailmap and MAINTAINERS updates"
* tag 'mm-hotfixes-stable-2022-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm/oom_kill.c: fix vm_oom_kill_table[] ifdeffery
x86/kexec: fix memory leak of elf header buffer
mm/memremap: fix missing call to untrack_pfn() in pagemap_range()
mm: page_isolation: use compound_nr() correctly in isolate_single_pageblock()
mm: hugetlb_vmemmap: fix CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON
MAINTAINERS: add maintainer information for z3fold
mailmap: update Josh Poimboeuf's email
