The lazy_rcu_shrink_count() shrinker function is registered even in
kernels built with CONFIG_RCU_LAZY=n, in which case this function
uselessly consumes cycles learning that no CPU has any lazy callbacks
queued.
This commit therefore registers this shrinker function only in the kernels
built with CONFIG_RCU_LAZY=y, where it might actually do something useful.
Signed-off-by: Zqiang <qiang1.zhang@intel.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
For kernels built with CONFIG_NO_HZ_FULL=y, the following scenario can result
in the scheduling-clock interrupt remaining enabled on a holdout CPU after
its quiescent state has been reported:
CPU1 CPU2
rcu_report_exp_cpu_mult synchronize_rcu_expedited_wait
acquires rnp->lock mask = rnp->expmask;
for_each_leaf_node_cpu_mask(rnp, cpu, mask)
rnp->expmask = rnp->expmask & ~mask; rdp = per_cpu_ptr(&rcu_data, cpu1);
for_each_leaf_node_cpu_mask(rnp, cpu, mask)
rdp = per_cpu_ptr(&rcu_data, cpu1);
if (!rdp->rcu_forced_tick_exp)
continue; rdp->rcu_forced_tick_exp = true;
tick_dep_set_cpu(cpu1, TICK_DEP_BIT_RCU_EXP);
The problem is that CPU2's sampling of rnp->expmask is obsolete by the
time it invokes tick_dep_set_cpu(), and CPU1 is not guaranteed to see
CPU2's store to ->rcu_forced_tick_exp in time to clear it. And even if
CPU1 does see that store, it might invoke tick_dep_clear_cpu() before
CPU2 got around to executing its tick_dep_set_cpu(), which would still
leave the victim CPU with its scheduler-clock tick running.
Either way, an nohz_full real-time application running on the victim
CPU would have its latency needlessly degraded.
Note that expedited RCU grace periods look at context-tracking
information, and so if the CPU is executing in nohz_full usermode
throughout, that CPU cannot be victimized in this manner.
This commit therefore causes synchronize_rcu_expedited_wait to hold
the rcu_node structure's ->lock when checking for holdout CPUs, setting
TICK_DEP_BIT_RCU_EXP, and invoking tick_dep_set_cpu(), thus preventing
this race.
Signed-off-by: Zqiang <qiang1.zhang@intel.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
This commit saves a line of code by switching from strncpy() to strscpy()
by permitting the later NUL assignment to be removed. While in the area,
save another line by taking advantage of 100 characters.
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Xu Panda <xu.panda@zte.com.cn>
Signed-off-by: Yang Yang <yang.yang29@zte.com.cn>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
For CONFIG_NO_HZ_FULL systems, the tick_do_timer_cpu cannot be offlined.
However, cpu_is_hotpluggable() still returns true for those CPUs. This causes
torture tests that do offlining to end up trying to offline this CPU causing
test failures. Such failure happens on all architectures.
Fix the repeated error messages thrown by this (even if the hotplug errors are
harmless) by asking the opinion of the nohz subsystem on whether the CPU can be
hotplugged.
[ Apply Frederic Weisbecker feedback on refactoring tick_nohz_cpu_down(). ]
For drivers/base/ portion:
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Zhouyi Zhou <zhouzhouyi@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: rcu <rcu@vger.kernel.org>
Cc: stable@vger.kernel.org
Fixes: 2987557f52 ("driver-core/cpu: Expose hotpluggability to the rest of the kernel")
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
I have spent about two years studying and contributing to RCU,
and sharing RCU-related knowledge within my team, if possible,
please consider me as R ;-).
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Zqiang <qiang1.zhang@intel.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Just to be clear, the "M:" tag before my name is short of "Minions" ;-)
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
I have spent years learning / contributing to RCU with several features,
talks and presentations, with my most recent work being on Lazy-RCU.
Please consider me for M, so I can tell my wife why I spend a lot of my
weekends and evenings on this complicated and mysterious thing -- which is
mostly in the hopes of preventing the world from burning down because
everything runs on this one way or another. ;-)
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Now that the SRCU Kconfig option is unconditionally selected, there is
no longer any point in selecting it. Therefore, remove the "select SRCU"
Kconfig statements.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <x86@kernel.org>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Now that the SRCU Kconfig option is unconditionally selected, there is
no longer any point in selecting it. Therefore, remove the "select SRCU"
Kconfig statements from the various KVM Kconfig files.
Acked-by: Sean Christopherson <seanjc@google.com> (x86)
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <kvm@vger.kernel.org>
Acked-by: Marc Zyngier <maz@kernel.org> (arm64)
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Anup Patel <anup@brainfault.org> (riscv)
Acked-by: Heiko Carstens <hca@linux.ibm.com> (s390)
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Now that the SRCU Kconfig option is unconditionally selected, there is
no longer any point in selecting it. Therefore, remove the "select SRCU"
Kconfig statements.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: <linux-mm@kvack.org>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Now that all references to CONFIG_SRCU have been removed, it is time to
remove CONFIG_SRCU itself.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Petr Mladek <pmladek@suse.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
This commit adds a comment to help explain why the "else" clause of the
in_serving_softirq() "if" statement does not need to enforce a time limit.
The reason is that this "else" clause handles rcuoc kthreads that do not
block handlers for other softirq vectors.
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The kfree_rcu() macro is deprecated. Rename it to its new
kfree_rcu_mightsleep() name in this documentation.
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Correct spelling problems for Documentation/RCU/ as reported
by codespell.
Note: in RTFP.txt, there are other misspellings that are left as is
since they were used that way in email Subject: lines or in LWN.net
articles. [preemptable, Preemptable, synchonisation]
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: rcu@vger.kernel.org
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
There is an smp_mb() named "E" in srcu_flip() immediately before the
increment (flip) of the srcu_struct structure's ->srcu_idx.
The purpose of E is to order the preceding scan's read of lock counters
against the flipping of the ->srcu_idx, in order to prevent new readers
from continuing to use the old ->srcu_idx value, which might needlessly
extend the grace period.
However, this ordering is already enforced because of the control
dependency between the preceding scan and the ->srcu_idx flip.
This control dependency exists because atomic_long_read() is used
to scan the counts, because WRITE_ONCE() is used to flip ->srcu_idx,
and because ->srcu_idx is not flipped until the ->srcu_lock_count[] and
->srcu_unlock_count[] counts match. And such a match cannot happen when
there is an in-flight reader that started before the flip (observation
courtesy Mathieu Desnoyers).
The litmus test below (courtesy of Frederic Weisbecker, with changes
for ctrldep by Boqun and Joel) shows this:
C srcu
(*
* bad condition: P0's first scan (SCAN1) saw P1's idx=0 LOCK count inc, though P1 saw flip.
*
* So basically, the ->po ordering on both P0 and P1 is enforced via ->ppo
* (control deps) on both sides, and both P0 and P1 are interconnected by ->rf
* relations. Combining the ->ppo with ->rf, a cycle is impossible.
*)
{}
// updater
P0(int *IDX, int *LOCK0, int *UNLOCK0, int *LOCK1, int *UNLOCK1)
{
int lock1;
int unlock1;
int lock0;
int unlock0;
// SCAN1
unlock1 = READ_ONCE(*UNLOCK1);
smp_mb(); // A
lock1 = READ_ONCE(*LOCK1);
// FLIP
if (lock1 == unlock1) { // Control dep
smp_mb(); // E // Remove E and still passes.
WRITE_ONCE(*IDX, 1);
smp_mb(); // D
// SCAN2
unlock0 = READ_ONCE(*UNLOCK0);
smp_mb(); // A
lock0 = READ_ONCE(*LOCK0);
}
}
// reader
P1(int *IDX, int *LOCK0, int *UNLOCK0, int *LOCK1, int *UNLOCK1)
{
int tmp;
int idx1;
int idx2;
// 1st reader
idx1 = READ_ONCE(*IDX);
if (idx1 == 0) { // Control dep
tmp = READ_ONCE(*LOCK0);
WRITE_ONCE(*LOCK0, tmp + 1);
smp_mb(); /* B and C */
tmp = READ_ONCE(*UNLOCK0);
WRITE_ONCE(*UNLOCK0, tmp + 1);
} else {
tmp = READ_ONCE(*LOCK1);
WRITE_ONCE(*LOCK1, tmp + 1);
smp_mb(); /* B and C */
tmp = READ_ONCE(*UNLOCK1);
WRITE_ONCE(*UNLOCK1, tmp + 1);
}
}
exists (0:lock1=1 /\ 1:idx1=1)
More complicated litmus tests with multiple SRCU readers also show that
memory barrier E is not needed.
This commit therefore clarifies the comment on memory barrier E.
Why not also remove that redundant smp_mb()?
Because control dependencies are quite fragile due to their not being
recognized by most compilers and tools. Control dependencies therefore
exact an ongoing maintenance burden, and such a burden cannot be justified
in this slowpath. Therefore, that smp_mb() stays until such time as
its overhead becomes a measurable problem in a real workload running on
a real production system, or until such time as compilers start paying
attention to this sort of control dependency.
Co-developed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Co-developed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Co-developed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
"Please not that you *cannot* rely..." has a typo.
Fix it.
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The SRCU_SIZE_* names are not self-explanatory, so this commit therefore
adds comments to the definitions.
Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Zhang, Qiang1" <qiang1.zhang@intel.com>
To: rcu@vger.kernel.org
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The state space of the GP sequence number isn't documented and the
definitions of its special values are scattered. This commit therefore
gathers some common knowledge near the grace-period sequence-number
definitions.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
It returns following attributes:
locking range start
locking range length
read lock enabled
write lock enabled
lock state (RW, RO or LK)
It can be retrieved by user authority provided the authority
was added to locking range via prior IOC_OPAL_ADD_USR_TO_LR
ioctl command. The command was extended to add user in ACE that
allows to read attributes listed above.
Signed-off-by: Ondrej Kozina <okozina@redhat.com>
Tested-by: Luca Boccassi <bluca@debian.org>
Tested-by: Milan Broz <gmazyland@gmail.com>
Link: https://lore.kernel.org/r/20230405111223.272816-6-okozina@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Refactors current code querying single column to use the
new helper. Real multi column usage will be added later.
Signed-off-by: Ondrej Kozina <okozina@redhat.com>
Tested-by: Luca Boccassi <bluca@debian.org>
Tested-by: Milan Broz <gmazyland@gmail.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230405111223.272816-5-okozina@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Extend ACE set of locking range attributes accessible to user
authority. This patch allows user authority to get following
locking range attribues when user get added to locking range via
IOC_OPAL_ADD_USR_TO_LR:
locking range start
locking range end
read lock enabled
write lock enabled
read locked
write locked
lock on reset
active key
Note: Admin1 authority always remains in the ACE. Otherwise
it breaks current userspace expecting Admin1 in the ACE (sedutils).
See TCG OPAL2 s.4.3.1.7 "ACE_Locking_RangeNNNN_Get_RangeStartToActiveKey".
Signed-off-by: Ondrej Kozina <okozina@redhat.com>
Tested-by: Luca Boccassi <bluca@debian.org>
Tested-by: Milan Broz <gmazyland@gmail.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230405111223.272816-4-okozina@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move ACE construction away from add_user_to_lr routine
and refactor it to be used also in later code.
Also adds boolean operators defines from TCG Core
specification.
Signed-off-by: Ondrej Kozina <okozina@redhat.com>
Tested-by: Luca Boccassi <bluca@debian.org>
Tested-by: Milan Broz <gmazyland@gmail.com>
Link: https://lore.kernel.org/r/20230405111223.272816-3-okozina@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
While adding user authority in boolean ace value
of uid OPAL_LOCKINGRANGE_ACE_WRLOCKED or
OPAL_LOCKINGRANGE_ACE_RDLOCKED, it was added twice.
It seemed redundant when only single authority was added
in the set method aka { authority1, authority1, OR }:
TCG Storage Architecture Core Specification, 5.1.3.3 ACE_expression
"This is an alternative type where the options are either a uidref to an
Authority object or one of the boolean_ACE (AND = 0 and OR = 1) options.
This type is used within the AC_element list to form a postfix Boolean
expression of Authorities."
Signed-off-by: Ondrej Kozina <okozina@redhat.com>
Tested-by: Luca Boccassi <bluca@debian.org>
Tested-by: Milan Broz <gmazyland@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20230405111223.272816-2-okozina@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge series from Tharun Kumar P <tharunkumar.pasumarthi@microchip.com>:
This patch series fixes the following bugs in spi-pci1xxxx driver:
1. Length of SPI transactions is improper
2. SPI transactions fail after suspend and resume
3. Incorrect implementation of pci1xxxx_spi_set_cs API
The osc_32k supports #clock-cells as 0, using an id is wrong, drop it.
Fixes: a6a355ede5 ("arm64: dts: imx8mm-evk: Add 32.768 kHz clock to PMIC")
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Marco Felsch <m.felsch@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
After commit 16988c7429 ("of/address: introduce of_address_count() helper"),
We can use of_address_count() to instead of open-coding it.
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Since commit 8b41fc4454 ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations
are used to identify modules. As a consequence, uses of the macro
in non-modules will cause modprobe to misidentify their containing
object file as a module when it is not (false positives), and modprobe
might succeed rather than failing with a suitable error message.
So remove it in the files in this commit, none of which can be built as
modules.
Signed-off-by: Nick Alcock <nick.alcock@oracle.com>
Suggested-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: linux-modules@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Hitomi Hasegawa <hasegawa-hitomi@fujitsu.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: linux-tegra@vger.kernel.org
Signed-off-by: Thierry Reding <treding@nvidia.com>
Since commit 8b41fc4454 ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations
are used to identify modules. As a consequence, uses of the macro
in non-modules will cause modprobe to misidentify their containing
object file as a module when it is not (false positives), and modprobe
might succeed rather than failing with a suitable error message.
So remove it in the files in this commit, none of which can be built as
modules.
Signed-off-by: Nick Alcock <nick.alcock@oracle.com>
Suggested-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: linux-modules@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Hitomi Hasegawa <hasegawa-hitomi@fujitsu.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: linux-tegra@vger.kernel.org
Signed-off-by: Thierry Reding <treding@nvidia.com>
Convert platform_get_resource(), devm_ioremap_resource() to a single
call to devm_platform_get_and_ioremap_resource(), as this is exactly
what this function does.
Signed-off-by: Ye Xingchen <ye.xingchen@zte.com.cn>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The TX2 SoM's SDIO WiFI card is connected via mmc@3440000 however it does
not look like the upstream kernel is even bothering to power this (and
the regulator framework shuts down this power rail post kernel init).
The issue seems to be a missing link for vccq from the MAX77620 PMIC's LDO5
which is labeled vddio_sdmmc3 (and not used anywhere else) to the mmc@3440000
node to ensure there is at leasr bus power.
Note this does not fix the WiFi issue on upstream kernels, there is still
something else missing that gets the BCM WiFi device to detect properly.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The default hpd_wait_us in panel_edp.c is 2 seconds. This makes the
sleep time in the polling of _ps8640_wait_hpd_asserted become 200ms.
Change it to a constant 20ms to speed up the function.
Signed-off-by: Pin-yen Lin <treapking@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Robert Foss <rfoss@kernel.org>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230331030204.1179524-1-treapking@chromium.org
A remove callback just returning 0 is equivalent to no remove callback
at all. So drop the useless function.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Sumit Gupta <sumitg@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Add the USB Type-C controller that is present on the Jetson AGX Orin
board. The ports for the Type-C controller are not populated yet, but
will be added later once the USB host and device support for Jetson AGX
Orin is enabled.
This is based upon a patch from Wayne Chang <waynec@nvidia.com>.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
mspi_apply_cpu_mode_quirks() always returns the passed bits_per_word
unmodified.
Make it return void, then don't check bits_per_word anymore on
return as it doesn't change.
bits_per_word is already checked by __spi_validate() so no risk to
have bits_per_word higher than 32.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/3142a7c40af12a160f4e134764f2c34da3d8e1e2.1680371809.git.christophe.leroy@csgroup.eu
Signed-off-by: Mark Brown <broonie@kernel.org>
On CPM, the RISC core is a lot more efficiant when doing transfers
in 16-bits chunks than in 8-bits chunks, but unfortunately the
words need to be byte swapped as seen in a previous commit.
So, for large tranfers with an even size, allocate a temporary tx
buffer and byte-swap data before and after transfer.
This change allows setting higher speed for transfer. For instance
on an MPC 8xx (CPM1 comms RISC processor), the documentation tells
that transfer in byte mode at 1 kbit/s uses 0.200% of CPM load
at 25 MHz while a word transfer at the same speed uses 0.032%
of CPM load. This means the speed can be 6 times higher in
word mode for the same CPM load.
For the time being, only do it on CPM1 as there must be a
trade-off between the CPM load reduction and the CPU load required
to byte swap the data.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/f2e981f20f92dd28983c3949702a09248c23845c.1680371809.git.christophe.leroy@csgroup.eu
Signed-off-by: Mark Brown <broonie@kernel.org>
For different reasons, fsl-spi driver performs bits_per_word
modifications for different reasons:
- On CPU mode, to minimise amount of interrupts
- On CPM/QE mode to work around controller byte order
For CPU mode that's done in fsl_spi_prepare_message() while
for CPM mode that's done in fsl_spi_setup_transfer().
Reunify all of it in fsl_spi_prepare_message(), and catch
impossible cases early through master's bits_per_word_mask
instead of returning EINVAL later.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/0ce96fe96e8b07cba0613e4097cfd94d09b8919a.1680371809.git.christophe.leroy@csgroup.eu
Signed-off-by: Mark Brown <broonie@kernel.org>
CPM has the same problem as QE so for CPM also use the fix added
by commit 0398fb7094 ("spi/spi_mpc8xxx: Fix QE mode Litte Endian"):
CPM mode uses Little Endian so words > 8 bits are byte swapped.
Workaround this by always enforcing wordsize 8 for 16 and 32 bits
words. Unfortunately this will not work for LSB transfers
where wordsize is > 8 bits so disable these for now.
Also limit the workaround to 16 and 32 bits words because it can
only work for multiples of 8-bits.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Joakim Tjernlund <Joakim.Tjernlund@infinera.com>
Fixes: 0398fb7094 ("spi/spi_mpc8xxx: Fix QE mode Litte Endian")
Link: https://lore.kernel.org/r/1b7d3e84b1128f42c1887dd2fb9cdf390f541bc1.1680371809.git.christophe.leroy@csgroup.eu
Signed-off-by: Mark Brown <broonie@kernel.org>
Hardware does not have support to disable individual chip select lines.
Disable all chip select lines by using SPI_FORCE_CE bit.
Fixes: 1cc0cbea71 ("spi: microchip: pci1xxxx: Add driver for SPI controller of PCI1XXXX PCIe switch")
Signed-off-by: Tharun Kumar P <tharunkumar.pasumarthi@microchip.com>
Link: https://lore.kernel.org/r/20230404171613.1336093-4-tharunkumar.pasumarthi@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>
pci1xxxx_spi_resume API masks SPI interrupt bit which prohibits interrupt
from coming to the host at the end of the transaction after suspend-resume.
This patch unmasks this bit at resume.
Fixes: 1cc0cbea71 ("spi: microchip: pci1xxxx: Add driver for SPI controller of PCI1XXXX PCIe switch")
Signed-off-by: Tharun Kumar P <tharunkumar.pasumarthi@microchip.com>
Link: https://lore.kernel.org/r/20230404171613.1336093-3-tharunkumar.pasumarthi@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>
In pci1xxxx_spi_transfer_one API, length of SPI transaction gets cleared
by setting of length mask. Set length of transaction only after masking
length field.
Fixes: 1cc0cbea71 ("spi: microchip: pci1xxxx: Add driver for SPI controller of PCI1XXXX PCIe switch")
Signed-off-by: Tharun Kumar P <tharunkumar.pasumarthi@microchip.com>
Link: https://lore.kernel.org/r/20230404171613.1336093-2-tharunkumar.pasumarthi@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>
clang with W=1 reports
drivers/usb/serial/quatech2.c:179:19: error: unused function
'qt2_setdevice' [-Werror,-Wunused-function]
static inline int qt2_setdevice(struct usb_device *dev, u8 *data)
^
This function is not used, so remove it.
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
ASoC is now using c2c_params instead of params. This patch replace it.
num_c2c_params (was num_params) was not mandatory before,
but let's set it by this patch.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/87jzytc2kp.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
ASoC is now using c2c_params instead of params. This patch replace it.
num_c2c_params (was num_params) was not mandatory before,
but let's set it by this patch.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/87lej9c2ky.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>