<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/drivers/pci, branch v4.14.263</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v4.14.263</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v4.14.263'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2022-01-27T08:00:48+00:00</updated>
<entry>
<title>PCI: Add function 1 DMA alias quirk for Marvell 88SE9125 SATA controller</title>
<updated>2022-01-27T08:00:48+00:00</updated>
<author>
<name>Yifeng Li</name>
<email>tomli@tomli.me</email>
</author>
<published>2021-12-02T06:35:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=b86b8fa8a134aec2d0a3e3645e55f0470865ca6c'/>
<id>urn:sha1:b86b8fa8a134aec2d0a3e3645e55f0470865ca6c</id>
<content type='text'>
commit e445375882883f69018aa669b67cbb37ec873406 upstream.

Like other SATA controller chips in the Marvell 88SE91xx series, the
Marvell 88SE9125 has the same DMA requester ID hardware bug that prevents
it from working under IOMMU.  Add it to the list of devices that need the
quirk.

Without this patch, device initialization fails with DMA errors:

  ata8: softreset failed (1st FIS failed)
  DMAR: DRHD: handling fault status reg 2
  DMAR: [DMA Write NO_PASID] Request device [03:00.1] fault addr 0xfffc0000 [fault reason 0x02] Present bit in context entry is clear
  DMAR: DRHD: handling fault status reg 2
  DMAR: [DMA Read NO_PASID] Request device [03:00.1] fault addr 0xfffc0000 [fault reason 0x02] Present bit in context entry is clear

After applying the patch, the controller can be successfully initialized:

  ata8: SATA link up 1.5 Gbps (SStatus 113 SControl 330)
  ata8.00: ATAPI: PIONEER BD-RW   BDR-207M, 1.21, max UDMA/100
  ata8.00: configured for UDMA/100
  scsi 7:0:0:0: CD-ROM            PIONEER  BD-RW   BDR-207M 1.21 PQ: 0 ANSI: 5

Link: https://lore.kernel.org/r/YahpKVR+McJVDdkD@work
Reported-by: Sam Bingner &lt;sam@bingner.com&gt;
Tested-by: Sam Bingner &lt;sam@bingner.com&gt;
Tested-by: Yifeng Li &lt;tomli@tomli.me&gt;
Signed-off-by: Yifeng Li &lt;tomli@tomli.me&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Reviewed-by: Krzysztof Wilczyński &lt;kw@linux.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>PCI/MSI: Mask MSI-X vectors only on success</title>
<updated>2021-12-22T08:18:00+00:00</updated>
<author>
<name>Stefan Roese</name>
<email>sr@denx.de</email>
</author>
<published>2021-12-14T11:49:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=b3c032b3ba09051ccbaec25856379570d5bd7b16'/>
<id>urn:sha1:b3c032b3ba09051ccbaec25856379570d5bd7b16</id>
<content type='text'>
commit 83dbf898a2d45289be875deb580e93050ba67529 upstream.

Masking all unused MSI-X entries is done to ensure that a crash kernel
starts from a clean slate, which correponds to the reset state of the
device as defined in the PCI-E specificion 3.0 and later:

 Vector Control for MSI-X Table Entries
 --------------------------------------

 "00: Mask bit:  When this bit is set, the function is prohibited from
                 sending a message using this MSI-X Table entry.
                 ...
                 This bit’s state after reset is 1 (entry is masked)."

A Marvell NVME device fails to deliver MSI interrupts after trying to
enable MSI-X interrupts due to that masking. It seems to take the MSI-X
mask bits into account even when MSI-X is disabled.

While not specification compliant, this can be cured by moving the masking
into the success path, so that the MSI-X table entries stay in device reset
state when the MSI-X setup fails.

[ tglx: Move it into the success path, add comment and amend changelog ]

Fixes: aa8092c1d1f1 ("PCI/MSI: Mask all unused MSI-X entries")
Signed-off-by: Stefan Roese &lt;sr@denx.de&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-pci@vger.kernel.org
Cc: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Cc: Michal Simek &lt;michal.simek@xilinx.com&gt;
Cc: Marek Vasut &lt;marex@denx.de&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211210161025.3287927-1-sr@denx.de
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>PCI/MSI: Clear PCI_MSIX_FLAGS_MASKALL on error</title>
<updated>2021-12-22T08:18:00+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2021-12-14T11:42:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=c9b5c1d450ac722572f158034b4167b490e9307e'/>
<id>urn:sha1:c9b5c1d450ac722572f158034b4167b490e9307e</id>
<content type='text'>
commit 94185adbfad56815c2c8401e16d81bdb74a79201 upstream.

PCI_MSIX_FLAGS_MASKALL is set in the MSI-X control register at MSI-X
interrupt setup time. It's cleared on success, but the error handling path
only clears the PCI_MSIX_FLAGS_ENABLE bit.

That's incorrect as the reset state of the PCI_MSIX_FLAGS_MASKALL bit is
zero. That can be observed via lspci:

        Capabilities: [b0] MSI-X: Enable- Count=67 Masked+

Clear the bit in the error path to restore the reset state.

Fixes: 438553958ba1 ("PCI/MSI: Enable and mask MSI-X early")
Reported-by: Stefan Roese &lt;sr@denx.de&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Tested-by: Stefan Roese &lt;sr@denx.de&gt;
Cc: linux-pci@vger.kernel.org
Cc: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Cc: Michal Simek &lt;michal.simek@xilinx.com&gt;
Cc: Marek Vasut &lt;marex@denx.de&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87tufevoqx.ffs@tglx
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>PCI: aardvark: Fix checking for link up via LTSSM state</title>
<updated>2021-12-08T07:46:51+00:00</updated>
<author>
<name>Pali Rohár</name>
<email>pali@kernel.org</email>
</author>
<published>2021-11-24T22:49:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=d490f96f86837d7216480f6e07bf550bacf69255'/>
<id>urn:sha1:d490f96f86837d7216480f6e07bf550bacf69255</id>
<content type='text'>
commit 661c399a651c11aaf83c45cbfe0b4a1fb7bc3179 upstream.

Current implementation of advk_pcie_link_up() is wrong as it marks also
link disabled or hot reset states as link up.

Fix it by marking link up only to those states which are defined in PCIe
Base specification 3.0, Table 4-14: Link Status Mapped to the LTSSM.

To simplify implementation, Define macros for every LTSSM state which
aardvark hardware can return in CFG_REG register.

Fix also checking for link training according to the same Table 4-14.
Define a new function advk_pcie_link_training() for this purpose.

Link: https://lore.kernel.org/r/20211005180952.6812-13-kabel@kernel.org
Fixes: 8c39d710363c ("PCI: aardvark: Add Aardvark PCI host controller driver")
Signed-off-by: Pali Rohár &lt;pali@kernel.org&gt;
Signed-off-by: Marek Behún &lt;kabel@kernel.org&gt;
Signed-off-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Reviewed-by: Marek Behún &lt;kabel@kernel.org&gt;
Cc: stable@vger.kernel.org
Cc: Remi Pommarel &lt;repk@triplefau.lt&gt;
Signed-off-by: Marek Behún &lt;kabel@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>PCI: aardvark: Fix link training</title>
<updated>2021-12-08T07:46:51+00:00</updated>
<author>
<name>Pali Rohár</name>
<email>pali@kernel.org</email>
</author>
<published>2021-11-24T22:49:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=edefd87df15a667ba383f9e255f3808e24cf1e6f'/>
<id>urn:sha1:edefd87df15a667ba383f9e255f3808e24cf1e6f</id>
<content type='text'>
commit f76b36d40beee0a13aa8f6aa011df0d7cbbb8a7f upstream.

Fix multiple link training issues in aardvark driver. The main reason of
these issues was misunderstanding of what certain registers do, since their
names and comments were misleading: before commit 96be36dbffac ("PCI:
aardvark: Replace custom macros by standard linux/pci_regs.h macros"), the
pci-aardvark.c driver used custom macros for accessing standard PCIe Root
Bridge registers, and misleading comments did not help to understand what
the code was really doing.

After doing more tests and experiments I've come to the conclusion that the
SPEED_GEN register in aardvark sets the PCIe revision / generation
compliance and forces maximal link speed. Both GEN3 and GEN2 values set the
read-only PCI_EXP_FLAGS_VERS bits (PCIe capabilities version of Root
Bridge) to value 2, while GEN1 value sets PCI_EXP_FLAGS_VERS to 1, which
matches with PCI Express specifications revisions 3, 2 and 1 respectively.
Changing SPEED_GEN also sets the read-only bits PCI_EXP_LNKCAP_SLS and
PCI_EXP_LNKCAP2_SLS to corresponding speed.

(Note that PCI Express rev 1 specification does not define PCI_EXP_LNKCAP2
 and PCI_EXP_LNKCTL2 registers and when SPEED_GEN is set to GEN1 (which
 also sets PCI_EXP_FLAGS_VERS set to 1), lspci cannot access
 PCI_EXP_LNKCAP2 and PCI_EXP_LNKCTL2 registers.)

Changing PCIe link speed can be done via PCI_EXP_LNKCTL2_TLS bits of
PCI_EXP_LNKCTL2 register. Armada 3700 Functional Specifications says that
the default value of PCI_EXP_LNKCTL2_TLS is based on SPEED_GEN value, but
tests showed that the default value is always 8.0 GT/s, independently of
speed set by SPEED_GEN. So after setting SPEED_GEN, we must also set value
in PCI_EXP_LNKCTL2 register via PCI_EXP_LNKCTL2_TLS bits.

Triggering PCI_EXP_LNKCTL_RL bit immediately after setting LINK_TRAINING_EN
bit actually doesn't do anything. Tests have shown that a delay is needed
after enabling LINK_TRAINING_EN bit. As triggering PCI_EXP_LNKCTL_RL
currently does nothing, remove it.

Commit 43fc679ced18 ("PCI: aardvark: Improve link training") introduced
code which sets SPEED_GEN register based on negotiated link speed from
PCI_EXP_LNKSTA_CLS bits of PCI_EXP_LNKSTA register. This code was added to
fix detection of Compex WLE900VX (Atheros QCA9880) WiFi GEN1 PCIe cards, as
otherwise these cards were "invisible" on PCIe bus (probably because they
crashed). But apparently more people reported the same issues with these
cards also with other PCIe controllers [1] and I was able to reproduce this
issue also with other "noname" WiFi cards based on Atheros QCA9890 chip
(with the same PCI vendor/device ids as Atheros QCA9880). So this is not an
issue in aardvark but rather an issue in Atheros QCA98xx chips. Also, this
issue only exists if the kernel is compiled with PCIe ASPM support, and a
generic workaround for this is to change PCIe Bridge to 2.5 GT/s link speed
via PCI_EXP_LNKCTL2_TLS_2_5GT bits in PCI_EXP_LNKCTL2 register [2], before
triggering PCI_EXP_LNKCTL_RL bit. This workaround also works when SPEED_GEN
is set to value GEN2 (5 GT/s). So remove this hack completely in the
aardvark driver and always set SPEED_GEN to value from 'max-link-speed' DT
property. Fix for Atheros QCA98xx chips is handled separately by patch [2].

These two things (code for triggering PCI_EXP_LNKCTL_RL bit and changing
SPEED_GEN value) also explain why commit 6964494582f5 ("PCI: aardvark:
Train link immediately after enabling training") somehow fixed detection of
those problematic Compex cards with Atheros chips: if triggering link
retraining (via PCI_EXP_LNKCTL_RL bit) was done immediately after enabling
link training (via LINK_TRAINING_EN), it did nothing. If there was a
specific delay, aardvark HW already initialized PCIe link and therefore
triggering link retraining caused the above issue. Compex cards triggered
link down event and disappeared from the PCIe bus.

Commit f4c7d053d7f7 ("PCI: aardvark: Wait for endpoint to be ready before
training link") added 100ms sleep before calling 'Start link training'
command and explained that it is a requirement of PCI Express
specification. But the code after this 100ms sleep was not doing 'Start
link training', rather it triggered PCI_EXP_LNKCTL_RL bit via PCIe Root
Bridge to put link into Recovery state.

The required delay after fundamental reset is already done in function
advk_pcie_wait_for_link() which also checks whether PCIe link is up.
So after removing the code which triggers PCI_EXP_LNKCTL_RL bit on PCIe
Root Bridge, there is no need to wait 100ms again. Remove the extra
msleep() call and update comment about the delay required by the PCI
Express specification.

According to Marvell Armada 3700 Functional Specifications, Link training
should be enabled via aardvark register LINK_TRAINING_EN after selecting
PCIe generation and x1 lane. There is no need to disable it prior resetting
card via PERST# signal. This disabling code was introduced in commit
5169a9851daa ("PCI: aardvark: Issue PERST via GPIO") as a workaround for
some Atheros cards. It turns out that this also is Atheros specific issue
and affects any PCIe controller, not only aardvark. Moreover this Atheros
issue was triggered by juggling with PCI_EXP_LNKCTL_RL, LINK_TRAINING_EN
and SPEED_GEN bits interleaved with sleeps. Now, after removing triggering
PCI_EXP_LNKCTL_RL, there is no need to explicitly disable LINK_TRAINING_EN
bit. So remove this code too. The problematic Compex cards described in
previous git commits are correctly detected in advk_pcie_train_link()
function even after applying all these changes.

Note that with this patch, and also prior this patch, some NVMe disks which
support PCIe GEN3 with 8 GT/s speed are negotiated only at the lowest link
speed 2.5 GT/s, independently of SPEED_GEN value. After manually triggering
PCI_EXP_LNKCTL_RL bit (e.g. from userspace via setpci), these NVMe disks
change link speed to 5 GT/s when SPEED_GEN was configured to GEN2. This
issue first needs to be properly investigated. I will send a fix in the
future.

On the other hand, some other GEN2 PCIe cards with 5 GT/s speed are
autonomously by HW autonegotiated at full 5 GT/s speed without need of any
software interaction.

Armada 3700 Functional Specifications describes the following steps for
link training: set SPEED_GEN to GEN2, enable LINK_TRAINING_EN, poll until
link training is complete, trigger PCI_EXP_LNKCTL_RL, poll until signal
rate is 5 GT/s, poll until link training is complete, enable ASPM L0s.

The requirement for triggering PCI_EXP_LNKCTL_RL can be explained by the
need to achieve 5 GT/s speed (as changing link speed is done by throw to
recovery state entered by PCI_EXP_LNKCTL_RL) or maybe as a part of enabling
ASPM L0s (but in this case ASPM L0s should have been enabled prior
PCI_EXP_LNKCTL_RL).

It is unknown why the original pci-aardvark.c driver was triggering
PCI_EXP_LNKCTL_RL bit before waiting for the link to be up. This does not
align with neither PCIe base specifications nor with Armada 3700 Functional
Specification. (Note that in older versions of aardvark, this bit was
called incorrectly PCIE_CORE_LINK_TRAINING, so this may be the reason.)

It is also unknown why Armada 3700 Functional Specification says that it is
needed to trigger PCI_EXP_LNKCTL_RL for GEN2 mode, as according to PCIe
base specification 5 GT/s speed negotiation is supposed to be entirely
autonomous, even if initial speed is 2.5 GT/s.

[1] - https://lore.kernel.org/linux-pci/87h7l8axqp.fsf@toke.dk/
[2] - https://lore.kernel.org/linux-pci/20210326124326.21163-1-pali@kernel.org/

Link: https://lore.kernel.org/r/20211005180952.6812-12-kabel@kernel.org
Signed-off-by: Pali Rohár &lt;pali@kernel.org&gt;
Signed-off-by: Marek Behún &lt;kabel@kernel.org&gt;
Signed-off-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Reviewed-by: Marek Behún &lt;kabel@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>PCI: aardvark: Fix PCIe Max Payload Size setting</title>
<updated>2021-12-08T07:46:51+00:00</updated>
<author>
<name>Pali Rohár</name>
<email>pali@kernel.org</email>
</author>
<published>2021-11-24T22:49:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=59e36d8f3418ca2ff48cb1dbcd310c0d3d3d9d56'/>
<id>urn:sha1:59e36d8f3418ca2ff48cb1dbcd310c0d3d3d9d56</id>
<content type='text'>
commit a4e17d65dafdd3513042d8f00404c9b6068a825c upstream.

Change PCIe Max Payload Size setting in PCIe Device Control register to 512
bytes to align with PCIe Link Initialization sequence as defined in Marvell
Armada 3700 Functional Specification. According to the specification,
maximal Max Payload Size supported by this device is 512 bytes.

Without this kernel prints suspicious line:

    pci 0000:01:00.0: Upstream bridge's Max Payload Size set to 256 (was 16384, max 512)

With this change it changes to:

    pci 0000:01:00.0: Upstream bridge's Max Payload Size set to 256 (was 512, max 512)

Link: https://lore.kernel.org/r/20211005180952.6812-3-kabel@kernel.org
Fixes: 8c39d710363c ("PCI: aardvark: Add Aardvark PCI host controller driver")
Signed-off-by: Pali Rohár &lt;pali@kernel.org&gt;
Signed-off-by: Marek Behún &lt;kabel@kernel.org&gt;
Signed-off-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Reviewed-by: Marek Behún &lt;kabel@kernel.org&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Marek Behún &lt;kabel@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>PCI: aardvark: Configure PCIe resources from 'ranges' DT property</title>
<updated>2021-12-08T07:46:51+00:00</updated>
<author>
<name>Pali Rohár</name>
<email>pali@kernel.org</email>
</author>
<published>2021-11-24T22:49:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=d4c0cd553ac9ca26300c07bbdd5168d1cacc4428'/>
<id>urn:sha1:d4c0cd553ac9ca26300c07bbdd5168d1cacc4428</id>
<content type='text'>
commit 64f160e19e9264a7f6d89c516baae1473b6f8359 upstream.

In commit 6df6ba974a55 ("PCI: aardvark: Remove PCIe outbound window
configuration") was removed aardvark PCIe outbound window configuration and
commit description said that was recommended solution by HW designers.

But that commit completely removed support for configuring PCIe IO
resources without removing PCIe IO 'ranges' from DTS files. After that
commit PCIe IO space started to be treated as PCIe MEM space and accessing
it just caused kernel crash.

Moreover implementation of PCIe outbound windows prior that commit was
incorrect. It completely ignored offset between CPU address and PCIe bus
address and expected that in DTS is CPU address always same as PCIe bus
address without doing any checks. Also it completely ignored size of every
PCIe resource specified in 'ranges' DTS property and expected that every
PCIe resource has size 128 MB (also for PCIe IO range). Again without any
check. Apparently none of PCIe resource has in DTS specified size of 128
MB. So it was completely broken and thanks to how aardvark mask works,
configuration was completely ignored.

This patch reverts back support for PCIe outbound window configuration but
implementation is a new without issues mentioned above. PCIe outbound
window is required when DTS specify in 'ranges' property non-zero offset
between CPU and PCIe address space. To address recommendation by HW
designers as specified in commit description of 6df6ba974a55, set default
outbound parameters as PCIe MEM access without translation and therefore
for this PCIe 'ranges' it is not needed to configure PCIe outbound window.
For PCIe IO space is needed to configure aardvark PCIe outbound window.

This patch fixes kernel crash when trying to access PCIe IO space.

Link: https://lore.kernel.org/r/20210624215546.4015-2-pali@kernel.org
Signed-off-by: Pali Rohár &lt;pali@kernel.org&gt;
Signed-off-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Cc: stable@vger.kernel.org # 6df6ba974a55 ("PCI: aardvark: Remove PCIe outbound window configuration")
Signed-off-by: Marek Behún &lt;kabel@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>PCI: aardvark: Remove PCIe outbound window configuration</title>
<updated>2021-12-08T07:46:51+00:00</updated>
<author>
<name>Evan Wang</name>
<email>xswang@marvell.com</email>
</author>
<published>2021-11-24T22:49:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=f06d6a0875f02513da06dd9dbc43da0449806850'/>
<id>urn:sha1:f06d6a0875f02513da06dd9dbc43da0449806850</id>
<content type='text'>
commit 6df6ba974a55678a2c7d9a0c06eb15cde0c4b184 upstream.

Outbound window is used to translate CPU space addresses to PCIe space
addresses when the CPU initiates PCIe transactions.

According to the suggestion of the HW designers, the recommended
solution is to use the default outbound parameters, even though the
current outbound window setting does not cause any known functional
issue.

This patch doesn't address any known functional issue, but aligns to
HW design guidelines, and removes code that isn't needed.

Signed-off-by: Evan Wang &lt;xswang@marvell.com&gt;
[Thomas: tweak commit log.]
Signed-off-by: Thomas Petazzoni &lt;thomas.petazzoni@bootlin.com&gt;
[lorenzo.pieralisi@arm.com: handled host-&gt;controller dir move]
Signed-off-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Reviewed-by: Victor Gu &lt;xigu@marvell.com&gt;
Reviewed-by: Nadav Haklai &lt;nadavh@marvell.com&gt;
Signed-off-by: Marek Behún &lt;kabel@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>PCI: aardvark: Update comment about disabling link training</title>
<updated>2021-12-08T07:46:51+00:00</updated>
<author>
<name>Pali Rohár</name>
<email>pali@kernel.org</email>
</author>
<published>2021-11-24T22:49:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=14910c1f4ff475031bb4114a399d742074340f04'/>
<id>urn:sha1:14910c1f4ff475031bb4114a399d742074340f04</id>
<content type='text'>
commit 1d1cd163d0de22a4041a6f1aeabcf78f80076539 upstream.

According to PCI Express Base Specifications (rev 4.0, 6.6.1
"Conventional reset"), after fundamental reset a 100ms delay is needed
prior to enabling link training.

Update comment in code to reflect this requirement.

Link: https://lore.kernel.org/r/20201202184659.3795-1-pali@kernel.org
Signed-off-by: Pali Rohár &lt;pali@kernel.org&gt;
Signed-off-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Signed-off-by: Marek Behún &lt;kabel@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>PCI: aardvark: Move PCIe reset card code to advk_pcie_train_link()</title>
<updated>2021-12-08T07:46:50+00:00</updated>
<author>
<name>Pali Rohár</name>
<email>pali@kernel.org</email>
</author>
<published>2021-11-24T22:49:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=7e81c76e62410f707363215ce1695ce0c92dfa6a'/>
<id>urn:sha1:7e81c76e62410f707363215ce1695ce0c92dfa6a</id>
<content type='text'>
commit d0c6a3475b033960e85ae2bf176b14cab0a627d2 upstream.

Move code which belongs to link training (delays and resets) into
advk_pcie_train_link() function, so everything related to link training,
including timings is at one place.

After experiments it can be observed that link training in aardvark
hardware is very sensitive to timings and delays, so it is a good idea to
have this code at the same place as link training calls.

This patch does not change behavior of aardvark initialization.

Link: https://lore.kernel.org/r/20200907111038.5811-6-pali@kernel.org
Tested-by: Marek Behún &lt;marek.behun@nic.cz&gt;
Signed-off-by: Pali Rohár &lt;pali@kernel.org&gt;
Signed-off-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Signed-off-by: Marek Behún &lt;kabel@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
</feed>
