linux-stable.git/drivers/pci, branch v5.7.7

PCI: amlogic: meson: Don't use FAST_LINK_MODE to set up link

2020-06-24T15:48:53+00:00

[ Upstream commit 87dccf09323fc363bd0d072fcc12b96622ab8c69 ]

The vim3l board does not work with a standard PCIe switch (ASM1184e),
spitting all kind of errors - hinting at HW misconfiguration (no link,
port enumeration issues, etc).

According to the the Synopsys DWC PCIe Reference Manual, in the section
dedicated to the PLCR register, bit 7 is described (FAST_LINK_MODE) as:

"Sets all internal timers to fast mode for simulation purposes."

it is sound to set this bit from a simulation perspective, but on actual
silicon, which expects timers to have a nominal value, it is not.

Make sure the FAST_LINK_MODE bit is cleared when configuring the RC
to solve this problem.

Link: https://lore.kernel.org/r/20200429164230.309922-1-maz@kernel.org
Fixes: 9c0ef6d34fdb ("PCI: amlogic: Add the Amlogic Meson PCIe controller driver")
Signed-off-by: Marc Zyngier 
[lorenzo.pieralisi@arm.com: commit log]
Signed-off-by: Lorenzo Pieralisi 
Reviewed-by: Neil Armstrong 
Acked-by: Rob Herring 
Signed-off-by: Sasha Levin

PCI: dwc: Fix inner MSI IRQ domain registration

2020-06-24T15:48:53+00:00

[ Upstream commit 0414b93e78d87ecc24ae1a7e61fe97deb29fa2f4 ]

On a system that uses the internal DWC MSI widget, I get this
warning from debugfs when CONFIG_GENERIC_IRQ_DEBUGFS is selected:

  debugfs: File ':soc:pcie@fc000000' in directory 'domains' already present!

This is due to the fact that the DWC MSI code tries to register two
IRQ domains for the same firmware node, without telling the low
level code how to distinguish them (by setting a bus token). This
further confuses debugfs which tries to create corresponding
files for each domain.

Fix it by tagging the inner domain as DOMAIN_BUS_NEXUS, which is
the closest thing we have as to "generic MSI".

Link: https://lore.kernel.org/r/20200501113921.366597-1-maz@kernel.org
Signed-off-by: Marc Zyngier 
Signed-off-by: Lorenzo Pieralisi 
Acked-by: Jingoo Han 
Signed-off-by: Sasha Levin

PCI: dwc: pci-dra7xx: Use devm_platform_ioremap_resource_byname()

2020-06-24T15:48:53+00:00

[ Upstream commit c8a119779f5609de8dcd98630f71cc7f1b2e4e8c ]

platform_get_resource() may fail and return NULL, so we had better
check its return value to avoid a NULL pointer dereference a bit later
in the code. Fix it to use devm_platform_ioremap_resource_byname()
instead of calling platform_get_resource_byname() and devm_ioremap().

Link: https://lore.kernel.org/r/20200429015027.134485-1-weiyongjun1@huawei.com
Signed-off-by: Wei Yongjun 
[lorenzo.pieralisi@arm.com: commit log]
Signed-off-by: Lorenzo Pieralisi 
Signed-off-by: Sasha Levin

PCI/PTM: Inherit Switch Downstream Port PTM settings from Upstream Port

2020-06-24T15:48:53+00:00

[ Upstream commit 7b38fd9760f51cc83d80eed2cfbde8b5ead9e93a ]

Except for Endpoints, we enable PTM at enumeration-time.  Previously we did
not account for the fact that Switch Downstream Ports are not permitted to
have a PTM capability; their PTM behavior is controlled by the Upstream
Port (PCIe r5.0, sec 7.9.16).  Since Downstream Ports don't have a PTM
capability, we did not mark them as "ptm_enabled", which meant that
pci_enable_ptm() on an Endpoint failed because there was no PTM path to it.

Mark Downstream Ports as "ptm_enabled" if their Upstream Port has PTM
enabled.

Fixes: eec097d43100 ("PCI: Add pci_enable_ptm() for drivers to enable PTM on endpoints")
Reported-by: Aditya Paluri 
Signed-off-by: Bjorn Helgaas 
Signed-off-by: Sasha Levin

PCI: aardvark: Issue PERST via GPIO

2020-06-24T15:48:48+00:00

[ Upstream commit 5169a9851daaa2782a7bd2bb83d5b1bd224b2879 ]

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 
Signed-off-by: Pali Rohár 
Signed-off-by: Lorenzo Pieralisi 
Acked-by: Thomas Petazzoni 
Signed-off-by: Sasha Levin

PCI: aardvark: Improve link training

2020-06-24T15:48:48+00:00

[ Upstream commit 43fc679ced18006b12d918d7a8a4af392b7fbfe7 ]

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 
Signed-off-by: Pali Rohár 
Signed-off-by: Marek Behún 
Signed-off-by: Lorenzo Pieralisi 
Reviewed-by: Rob Herring 
Acked-by: Thomas Petazzoni 
Signed-off-by: Sasha Levin

PCI: aardvark: Train link immediately after enabling training

2020-06-24T15:48:48+00:00

[ Upstream commit 6964494582f56a3882c2c53b0edbfe99eb32b2e1 ]

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: f4c7d053d7f7 ("PCI: aardvark: Wait for endpoint to be ready...")
Tested-by: Tomasz Maciej Nowak 
Signed-off-by: Pali Rohár 
Signed-off-by: Lorenzo Pieralisi 
Acked-by: Rob Herring 
Acked-by: Thomas Petazzoni 
Signed-off-by: Sasha Levin

PCI/PM: Assume ports without DLL Link Active train links in 100 ms

2020-06-24T15:48:47+00:00

[ Upstream commit ec411e02b7a2e785a4ed9ed283207cd14f48699d ]

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 
Tested-by: Kai-Heng Feng 
Signed-off-by: Mika Westerberg 
Signed-off-by: Bjorn Helgaas 
Signed-off-by: Sasha Levin

PCI: Fix pci_register_host_bridge() device_register() error handling

2020-06-24T15:48:45+00:00

[ Upstream commit 1b54ae8327a4d630111c8d88ba7906483ec6010b ]

If device_register() has an error, we should bail out of
pci_register_host_bridge() rather than continuing on.

Fixes: 37d6a0a6f470 ("PCI: Add pci_register_host_bridge() interface")
Link: https://lore.kernel.org/r/20200513223859.11295-1-robh@kernel.org
Signed-off-by: Rob Herring 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Lorenzo Pieralisi 
Reviewed-by: Arnd Bergmann 
Signed-off-by: Sasha Levin

PCI: brcmstb: Assert fundamental reset on initialization

2020-06-24T15:48:42+00:00

[ Upstream commit 22e21e51ce755399fd42055a3f668ee4af370881 ]

While preparing the driver for upstream this detail was missed.

If not asserted during the initialization process, devices connected on
the bus will not be made aware of the internal reset happening. This,
potentially resulting in unexpected behavior.

Link: https://lore.kernel.org/r/20200507172020.18000-1-nsaenzjulienne@suse.de
Fixes: c0452137034b ("PCI: brcmstb: Add Broadcom STB PCIe host controller driver")
Signed-off-by: Nicolas Saenz Julienne 
Signed-off-by: Lorenzo Pieralisi 
Acked-by: Florian Fainelli 
Signed-off-by: Sasha Levin