This register is applicable only when the controller is configured for
Endpoint mode, which is not the case for the current version of this
driver.
Attempting to remove this code though caused some ath10k cards to stop
working, so for some unknown reason it is needed here.
This should be investigated and a comment explaining this should be put
before the code, so we add a FIXME comment for now.
Link: https://lore.kernel.org/r/20200430080625.26070-7-pali@kernel.org
Tested-by: Tomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Add support for issuing PERST via GPIO specified in 'reset-gpios'
property (as described in PCI device tree bindings).
Some buggy cards (e.g. Compex WLE900VX or WLE1216) are not detected
after reboot when PERST is not issued during driver initialization.
If bootloader already enabled link training then issuing PERST has no
effect for some buggy cards (e.g. Compex WLE900VX) and these cards are
not detected. We therefore clear the LINK_TRAINING_EN register before.
It was observed that Compex WLE900VX card needs to be in PERST reset
for at least 10ms if bootloader enabled link training.
Tested on Turris MOX.
Link: https://lore.kernel.org/r/20200430080625.26070-6-pali@kernel.org
Tested-by: Tomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Currently the aardvark driver trains link in PCIe gen2 mode. This may
cause some buggy gen1 cards (such as Compex WLE900VX) to be unstable or
even not detected. Moreover when ASPM code tries to retrain link second
time, these cards may stop responding and link goes down. If gen1 is
used this does not happen.
Unconditionally forcing gen1 is not a good solution since it may have
performance impact on gen2 cards.
To overcome this, read 'max-link-speed' property (as defined in PCI
device tree bindings) and use this as max gen mode. Then iteratively try
link training at this mode or lower until successful. After successful
link training choose final controller gen based on Negotiated Link Speed
from Link Status register, which should match card speed.
Link: https://lore.kernel.org/r/20200430080625.26070-5-pali@kernel.org
Tested-by: Tomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Trying to change Link Status register does not have any effect as this
is a read-only register. Trying to overwrite bits for Negotiated Link
Width does not make sense.
In future proper change of link width can be done via Lane Count Select
bits in PCIe Control 0 register.
Trying to unconditionally enable ASPM L0s via ASPM Control bits in Link
Control register is wrong. There should be at least some detection if
endpoint supports L0s as isn't mandatory.
Moreover ASPM Control bits in Link Control register are controlled by
pcie/aspm.c code which sets it according to system ASPM settings,
immediately after aardvark driver probes. So setting these bits by
aardvark driver has no long running effect.
Remove code which touches ASPM L0s bits from this driver and let
kernel's ASPM implementation to set ASPM state properly.
Some users are reporting issues that this code is problematic for some
Intel wifi cards and removing it fixes them, see e.g.:
https://bugzilla.kernel.org/show_bug.cgi?id=196339
If problems with Intel wifi cards occur even after this commit, then
pcie/aspm.c code could be modified / hooked to not enable ASPM L0s state
for affected problematic cards.
Link: https://lore.kernel.org/r/20200430080625.26070-3-pali@kernel.org
Tested-by: Tomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Adding even 100ms (PCI_PM_D3COLD_WAIT) delay between enabling link
training and starting link training causes detection issues with some
buggy cards (such as Compex WLE900VX).
Move the code which enables link training immediately before the one
which starts link traning.
This fixes detection issues of Compex WLE900VX card on Turris MOX after
cold boot.
Link: https://lore.kernel.org/r/20200430080625.26070-2-pali@kernel.org
Fixes: f4c7d053d7 ("PCI: aardvark: Wait for endpoint to be ready...")
Tested-by: Tomasz Maciej Nowak <tmn505@gmail.com>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Kai-Heng Feng reported that it takes a long time (> 1 s) to resume
Thunderbolt-connected devices from both runtime suspend and system sleep
(s2idle).
This was because some Downstream Ports that support > 5 GT/s do not also
support Data Link Layer Link Active reporting. Per PCIe r5.0 sec 6.6.1:
With a Downstream Port that supports Link speeds greater than 5.0 GT/s,
software must wait a minimum of 100 ms after Link training completes
before sending a Configuration Request to the device immediately below
that Port. Software can determine when Link training completes by polling
the Data Link Layer Link Active bit or by setting up an associated
interrupt (see Section 6.7.3.3).
Sec 7.5.3.6 requires such Ports to support DLL Link Active reporting, but
at least the Intel JHL6240 Thunderbolt 3 Bridge [8086:15c0] and the Intel
JHL7540 Thunderbolt 3 Bridge [8086:15ea] do not.
Previously we tried to wait for Link training to complete, but since there
was no DLL Link Active reporting, all we could do was wait the worst-case
1000 ms, then another 100 ms.
Instead of using the supported speeds to determine whether to wait for Link
training, check whether the port supports DLL Link Active reporting. The
Ports in question do not, so we'll wait only the 100 ms required for Ports
that support Link speeds <= 5 GT/s.
This of course assumes these Ports always train the Link within 100 ms even
if they are operating at > 5 GT/s, which is not required by the spec.
[bhelgaas: commit log, comment]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206837
Link: https://lore.kernel.org/r/20200514133043.27429-1-mika.westerberg@linux.intel.com
Reported-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The caller of pcie_wait_for_link_delay() specifies the time to wait after
the link becomes active. When the downstream port doesn't support link
active reporting, obviously we can't tell when the link becomes active, so
we waited the worst-case time (1000 ms) plus 100 ms, ignoring the delay
from the caller.
Instead, wait for 1000 ms + the delay from the caller.
Fixes: 4827d63891 ("PCI/PM: Add pcie_wait_for_link_delay()")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Root Complex Integrated Endpoints (RCiEPs) do not have an upstream bridge,
so pci_configure_mps() previously ignored them, which may result in reduced
performance.
Instead, program the Max_Payload_Size of RCiEPs to the maximum supported
value (unless it is limited for the PCIE_BUS_PEER2PEER case). This also
affects the subsequent programming of Max_Read_Request_Size because Linux
programs MRRS based on the MPS value.
Fixes: 9dae3a9729 ("PCI: Move MPS configuration check to pci_configure_device()")
Link: https://lore.kernel.org/r/1585343775-4019-1-git-send-email-ashok.raj@intel.com
Tested-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org
The PCI code has several paths where the struct pci_host_bridge is freed
directly. This is wrong because it contains a struct device which is
refcounted and should be freed using put_device(). This can result in
use-after-free errors. I think this problem has existed since 2012 with
commit 7b54366358 ("PCI: add generic device into pci_host_bridge
struct"). It generally hasn't mattered as most host bridge drivers are
still built-in and can't unbind.
The problem is a struct device should never be freed directly once
device_initialize() is called and a ref is held, but that doesn't happen
until pci_register_host_bridge(). There's then a window between allocating
the host bridge and pci_register_host_bridge() where kfree should be used.
This is fragile and requires callers to do the right thing. To fix this, we
need to split device_register() into device_initialize() and device_add()
calls, so that the host bridge struct is always freed by using a
put_device().
devm_pci_alloc_host_bridge() is using devm_kzalloc() to allocate struct
pci_host_bridge which will be freed directly. Instead, we can use a custom
devres action to call put_device().
Link: https://lore.kernel.org/r/20200513223859.11295-2-robh@kernel.org
Reported-by: Anders Roxell <anders.roxell@linaro.org>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
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 as 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]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type [1]. There are some instances of code in which
the sizeof() operator is being incorrectly/erroneously applied to
zero-length arrays, and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also help
to get completely rid of those sorts of issues.
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 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Link: https://lore.kernel.org/r/20200507190544.GA15633@embeddedor
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
When kdump is triggered, some PCI devices may have not been shut down
cleanly before the kdump kernel starts.
This causes the initial attempt to enter D0 state in the kdump kernel to
fail with invalid device state returned from Hyper-V host.
When this happens, explicitly call hv_pci_bus_exit() and retry to enter
the D0 state.
Link: https://lore.kernel.org/r/20200507050300.10974-1-weh@microsoft.com
Signed-off-by: Wei Hu <weh@microsoft.com>
[lorenzo.pieralisi@arm.com: commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
In some error cases in hv_pci_probe(), allocated resources are not freed.
Fix this by adding a field to keep track of the high water mark for slots
that have resources allocated to them. In case of an error, this high
water mark is used to know which slots have resources that must be released.
Since slots are numbered starting with zero, a value of -1 indicates no
slots have been allocated resources. There may be unused slots in the range
between slot 0 and the high water mark slot, but these slots are already
ignored by the existing code in the allocate and release loops with the call
to get_pcichild_wslot().
Link: https://lore.kernel.org/r/20200507050211.10923-1-weh@microsoft.com
Signed-off-by: Wei Hu <weh@microsoft.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Some informal internal experiments has shown that the BrcmSTB ASPM L0s
savings may introduce an undesirable noise signal on some customers'
boards. In addition, L0s was found lacking in realized power savings,
especially relative to the L1 ASPM component. This is BrcmSTB's
experience and may not hold for others. At any rate, if the
'aspm-no-l0s' property is present L0s will be disabled.
Link: https://lore.kernel.org/r/20200507201544.43432-5-james.quinlan@broadcom.com
Signed-off-by: Jim Quinlan <jquinlan@broadcom.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Both Pericom OHCI and EHCI devices advertise PME# support from all power
states:
06:00.0 USB controller [0c03]: Pericom Semiconductor PI7C9X442SL USB OHCI Controller [12d8:400e] (rev 01) (prog-if 10 [OHCI])
Subsystem: Pericom Semiconductor PI7C9X442SL USB OHCI Controller [12d8:400e]
Capabilities: [80] Power Management version 3
Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=375mA PME(D0+,D1+,D2+,D3hot+,D3cold+)
06:00.2 USB controller [0c03]: Pericom Semiconductor PI7C9X442SL USB EHCI Controller [12d8:400f] (rev 01) (prog-if 20 [EHCI])
Subsystem: Pericom Semiconductor PI7C9X442SL USB EHCI Controller [12d8:400f]
Capabilities: [80] Power Management version 3
Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=375mA PME(D0+,D1+,D2+,D3hot+,D3cold+)
But testing shows that it's unreliable: there is a 20% chance PME# won't be
asserted when a USB device is plugged.
Remove PME support for both devices to make USB plugging work reliably.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=205981
Link: https://lore.kernel.org/r/20200508065343.32751-2-kai.heng.feng@canonical.com
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org
The outbound windows (PCIEPAUR(x), PCIEPALR(x)) describe a mapping between
a CPU address (which is determined by the window number 'x') and a
programmed PCI address - Thus allowing the controller to translate CPU
accesses into PCI accesses.
However the existing code incorrectly writes the CPU address - lets fix
this by writing the PCI address instead.
For memory transactions, existing DT users describe a 1:1 identity mapping
and thus this change should have no effect. However the same isn't true for
I/O.
Link: https://lore.kernel.org/r/20191004132941.6660-1-andrew.murray@arm.com
Fixes: c25da47788 ("PCI: rcar: Add Renesas R-Car PCIe driver")
Tested-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Vasut <marek.vasut+renesas@gmail.com>
When unbinding pci_epf_test, pci_epf_test_clean_dma_chan() is called in
pci_epf_test_unbind() even though epf_test->dma_supported is false.
As a result, dma_release_channel() will trigger a NULL pointer
dereference because dma_chan is not set.
Avoid calling dma_release_channel() if epf_test->dma_supported
is false.
Link: https://lore.kernel.org/r/1587540287-10458-1-git-send-email-hayashi.kunihiko@socionext.com
Fixes: 5ebf3fc59b ("PCI: endpoint: functions/pci-epf-test: Add DMA support to transfer data")
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
[lorenzo.pieralisi@arm.com: commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
If we fails somewhere in 'v3_pci_probe()', we need to free 'host'.
Use the managed version of 'pci_alloc_host_bridge()' to do that easily.
The use of managed resources is already widely used in this driver.
Link: https://lore.kernel.org/r/20200418081637.1585-1-christophe.jaillet@wanadoo.fr
Fixes: 68a15eb7bd ("PCI: v3-semi: Add V3 Semiconductor PCI host driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
[lorenzo.pieralisi@arm.com: commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
When resizing a BAR, pci_reassign_bridge_resources() is invoked to bring
the bridge windows of parent bridges in line with the new BAR assignment.
This assumes the device whose BAR is being resized lives on a subordinate
bus, but this is not necessarily the case. A device may live on the root
bus, in which case dev->bus->self is NULL, and passing a NULL pci_dev
pointer to pci_reassign_bridge_resources() will cause it to crash.
So let's make the call to pci_reassign_bridge_resources() conditional on
whether dev->bus->self is non-NULL in the first place.
Fixes: 8bb705e3e7 ("PCI: Add pci_resize_resource() for resizing BARs")
Link: https://lore.kernel.org/r/20200421162256.26887-1-ardb@kernel.org
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Per the PCI Firmware spec, r3.2, sec 4.5.1, the OS can request control of
AER via bit 3 of the _OSC Control Field. In the returned value of the
Control Field:
The firmware sets [bit 3] to 1 to grant control over PCI Express Advanced
Error Reporting. ... after control is transferred to the operating
system, firmware must not modify the Advanced Error Reporting Capability.
If control of this feature was requested and denied or was not requested,
firmware returns this bit set to 0.
Previously the pci_root driver looked at the HEST FIRMWARE_FIRST bit to
determine whether to request ownership of the AER Capability. This was
based on ACPI spec v6.3, sec 18.3.2.4, and similar sections, which say
things like:
Bit [0] - FIRMWARE_FIRST: If set, indicates that system firmware will
handle errors from this source first.
Bit [1] - GLOBAL: If set, indicates that the settings contained in this
structure apply globally to all PCI Express Devices.
These ACPI references don't say anything about ownership of the AER
Capability.
Remove use of the FIRMWARE_FIRST bit and rely only on the _OSC bit to
determine whether we have control of the AER Capability.
Link: https://lore.kernel.org/r/20181115231605.24352-1-mr.nuke.me@gmail.com/ v1
Link: https://lore.kernel.org/r/20190326172343.28946-1-mr.nuke.me@gmail.com/ v2
Link: https://lore.kernel.org/r/67af2931705bed9a588b5a39d369cb70b9942190.1587925636.git.sathyanarayanan.kuppuswamy@linux.intel.com
[bhelgaas: commit log, note: Alex posted this identical patch 18 months
ago, and I failed to apply it then, so I made him the author, added links
to his postings, and added his Signed-off-by]
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jon Derrick <jonathan.derrick@intel.com>
The Physical function should not be disabled until no virtual
functions depends on it.
Let's force the user to first use echo 0 > sriov_numfs before
allowing to disable the PF with echo 0 > power.
Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
We allow multiple functions on a single bus.
We suppress the ZPCI_DEVFN definition and replace its
occurences with zpci->devfn.
We verify the number of device during the registration.
There can never be more domains in use than existing
devices, so we do not need to verify the count of domain
after having verified the count of devices.
Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
The zPCI bus is in charge to handle common zPCI resources for
zPCI devices.
Creating the zPCI bus, the PCI bus, the zPCI devices and the
PCI devices and hotplug slots
done in a specific order:
- PCI hotplug slot creation needs a PCI bus
- PCI bus needs a PCI domain
which is reported by the pci_domain_nr() when setting up the
host bridge
- PCI domain is set from the zPCI with devfn 0
this is necessary to have a reproducible enumeration
Therefore we can not create devices or hotplug slots for any PCI
device associated with a zPCI device before having discovered
the function zero of the bus.
The discovery and initialization of devices can be done at several
points in the code:
- On Events, serialized in a thread context
- On initialization, in the kernel init thread context
- When powering on the hotplug slot, in a user thread context
The removal of devices and their parent bus may also be done on
events or for devices when powering down the slot.
To guarantee the existence of the bus and devices until they are
no more needed we use kref in zPCI bus and introduce a reference
count in the zPCI devices.
In this patch the zPCI bus still only accept a device with
a devfn 0.
Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Drivers should not be selected by default because that bloats the kernel
for people who don't need them.
Enable CONFIG_PCI_DRA7XX_HOST by default only if SOC_DRA7XX.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: linux-omap@vger.kernel.org
