The PCIE_MSI_PAYLOAD_REG contains 16-bit MSI number, not only lower
8 bits. Fix reading content of this register and add a comment
describing the access to this register.
Link: https://lore.kernel.org/r/20211028185659.20329-4-kabel@kernel.org
Fixes: 8c39d71036 ("PCI: aardvark: Add Aardvark PCI host controller driver")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org
MSI domain callback .alloc() (implemented by advk_msi_irq_domain_alloc()
function) should return zero on success, since non-zero value indicates
failure.
When the driver was converted to generic MSI API in commit f21a8b1b68
("PCI: aardvark: Move to MSI handling using generic MSI support"), it
was converted so that it returns hwirq number.
Fix this.
Link: https://lore.kernel.org/r/20211028185659.20329-3-kabel@kernel.org
Fixes: f21a8b1b68 ("PCI: aardvark: Move to MSI handling using generic MSI support")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org
Add support for reporting PCI_EXP_LNKSTA_DLLLA bit in Link Control register
on emulated bridge via current LTSSM state. Also correctly indicate DLLLA
capability via PCI_EXP_LNKCAP_DLLLARC bit in Link Control Capability
register.
Link: https://lore.kernel.org/r/20211005180952.6812-14-kabel@kernel.org
Fixes: 8a3ebd8de3 ("PCI: aardvark: Implement emulated root PCI bridge config space")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org
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: 8c39d71036 ("PCI: aardvark: Add Aardvark PCI host controller driver")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org
Cc: Remi Pommarel <repk@triplefau.lt>
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 96be36dbff ("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 43fc679ced ("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 6964494582 ("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 f4c7d053d7 ("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
5169a9851d ("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 <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
PCIe config space can be initialized also before pci_bridge_emul_init()
call, so move rootcap initialization after PCI config space initialization.
This simplifies the function a little since it removes one if (ret < 0)
check.
Link: https://lore.kernel.org/r/20211005180952.6812-11-kabel@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Commit 43f5c77bcb ("PCI: aardvark: Fix reporting CRS value") fixed
handling of CRS response and when CRSSVE flag was not enabled it marked CRS
response as failed transaction (due to simplicity).
But pci-aardvark.c driver is already waiting up to the PIO_RETRY_CNT count
for PIO config response and so we can with a small change implement
re-issuing of config requests as described in PCIe base specification.
This change implements re-issuing of config requests when response is CRS.
Set upper bound of wait cycles to around PIO_RETRY_CNT, afterwards the
transaction is marked as failed and an all-ones value is returned as
before.
We do this by returning appropriate error codes from function
advk_pcie_check_pio_status(). On CRS we return -EAGAIN and caller then
reissues transaction.
Link: https://lore.kernel.org/r/20211005180952.6812-10-kabel@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Avoid code repetition in advk_pcie_rd_conf() by handling errors with
goto jump, as is customary in kernel.
Link: https://lore.kernel.org/r/20211005180952.6812-9-kabel@kernel.org
Fixes: 43f5c77bcb ("PCI: aardvark: Fix reporting CRS value")
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
There are lot of undocumented interrupt bits. To prevent unwanted
spurious interrupts, fix all *_ALL_MASK macros to define all interrupt
bits, so that driver can properly mask all interrupts, including those
which are undocumented.
Link: https://lore.kernel.org/r/20211005180952.6812-8-kabel@kernel.org
Fixes: 8c39d71036 ("PCI: aardvark: Add Aardvark PCI host controller driver")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org
The PCIE_ISR1_REG says which interrupts are currently set / active,
including those which are masked.
The driver currently reads this register and looks if some unmasked
interrupts are active, and if not, it clears status bits of _all_
interrupts, including the masked ones.
This is incorrect, since, for example, some drivers may poll these bits.
Remove this clearing, and also remove this early return statement
completely, since it does not change functionality in any way.
Link: https://lore.kernel.org/r/20211005180952.6812-7-kabel@kernel.org
Fixes: 8c39d71036 ("PCI: aardvark: Add Aardvark PCI host controller driver")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org
Commit 366697018c ("PCI: aardvark: Add PHY support") introduced
configuration of PCIe Reference clock via PCIE_CORE_REF_CLK_REG register,
but did it incorrectly.
PCIe Reference clock differential pair is routed from system board to
endpoint card, so on CPU side it has output direction. Therefore it is
required to enable transmitting and disable receiving.
Default configuration according to Armada 3700 Functional Specifications is
enabled receiver part and disabled transmitter.
We need this change because otherwise PCIe Reference clock is configured to
some undefined state when differential pair is used for both transmitting
and receiving.
Fix this by disabling receiver part.
Link: https://lore.kernel.org/r/20211005180952.6812-6-kabel@kernel.org
Fixes: 366697018c ("PCI: aardvark: Add PHY support")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org
Commit 43f5c77bcb ("PCI: aardvark: Fix reporting CRS value") started
using CRSSVE flag for handling CRS responses.
PCI_EXP_RTCTL_CRSSVE flag is stored only in emulated config space buffer
and there is handler for PCI_EXP_RTCTL register. So every read operation
from config space automatically clears CRSSVE flag as it is not defined in
PCI_EXP_RTCTL read handler.
Fix this by reading current CRSSVE bit flag from emulated space buffer and
appending it to PCI_EXP_RTCTL read response.
Link: https://lore.kernel.org/r/20211005180952.6812-5-kabel@kernel.org
Fixes: 43f5c77bcb ("PCI: aardvark: Fix reporting CRS value")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Use dev_dbg() instead of dev_err() in advk_pcie_check_pio_status().
For example CRS is not an error status, it just says that the request
should be retried.
Link: https://lore.kernel.org/r/20211005180952.6812-4-kabel@kernel.org
Fixes: 8c39d71036 ("PCI: aardvark: Add Aardvark PCI host controller driver")
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
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: 8c39d71036 ("PCI: aardvark: Add Aardvark PCI host controller driver")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org
- Fix PIO config access status checking (Evan Wang)
- Increase config access polling delay to 1.5s (Pali Rohár)
- Add PCIe Root Capabilities to bridge emulation (Pali Rohár)
- Report Config Request Retry Status when Software Visibility enabled (Pali
Rohár)
- Add back configuration of PCIe resources from 'ranges' DT property and
pay attention to DT size and CPU/PCI offset to fix issues with I/O port
space (Pali Rohár)
- Serialize masking and unmasking legacy INTx interrupts (Pali Rohár)
* remotes/lorenzo/pci/aardvark:
PCI: aardvark: Fix masking and unmasking legacy INTx interrupts
PCI: aardvark: Configure PCIe resources from 'ranges' DT property
PCI: aardvark: Fix reporting CRS value
PCI: pci-bridge-emul: Add PCIe Root Capabilities Register
PCI: aardvark: Increase polling delay to 1.5s while waiting for PIO response
PCI: aardvark: Fix checking for PIO status
irq_mask and irq_unmask callbacks need to be properly guarded by raw spin
locks as masking/unmasking procedure needs atomic read-modify-write
operation on hardware register.
Link: https://lore.kernel.org/r/20210820155020.3000-1-pali@kernel.org
Reported-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
In commit 6df6ba974a ("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 6df6ba974a, 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 <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org # 6df6ba974a ("PCI: aardvark: Remove PCIe outbound window configuration")
Set CRSVIS flag in emulated root PCI bridge to indicate support for
Completion Retry Status.
Add check for CRSSVE flag from root PCI brige when issuing Configuration
Read Request via PIO to correctly returns fabricated CRS value as it is
required by PCIe spec.
Link: https://lore.kernel.org/r/20210722144041.12661-5-pali@kernel.org
Fixes: 8a3ebd8de3 ("PCI: aardvark: Implement emulated root PCI bridge config space")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org # e0d9d30b73 ("PCI: pci-bridge-emul: Fix big-endian support")
Measurements in different conditions showed that aardvark hardware PIO
response can take up to 1.44s. Increase wait timeout from 1ms to 1.5s to
ensure that we do not miss responses from hardware. After 1.44s hardware
returns errors (e.g. Completer abort).
The previous two patches fixed checking for PIO status, so now we can use
it to also catch errors which are reported by hardware after 1.44s.
After applying this patch, kernel can detect and print PIO errors to dmesg:
[ 6.879999] advk-pcie d0070000.pcie: Non-posted PIO Response Status: CA, 0xe00 @ 0x100004
[ 6.896436] advk-pcie d0070000.pcie: Posted PIO Response Status: COMP_ERR, 0x804 @ 0x100004
[ 6.913049] advk-pcie d0070000.pcie: Posted PIO Response Status: COMP_ERR, 0x804 @ 0x100010
[ 6.929663] advk-pcie d0070000.pcie: Non-posted PIO Response Status: CA, 0xe00 @ 0x100010
[ 6.953558] advk-pcie d0070000.pcie: Posted PIO Response Status: COMP_ERR, 0x804 @ 0x100014
[ 6.970170] advk-pcie d0070000.pcie: Non-posted PIO Response Status: CA, 0xe00 @ 0x100014
[ 6.994328] advk-pcie d0070000.pcie: Posted PIO Response Status: COMP_ERR, 0x804 @ 0x100004
Without this patch kernel prints only a generic error to dmesg:
[ 5.246847] advk-pcie d0070000.pcie: config read/write timed out
Link: https://lore.kernel.org/r/20210722144041.12661-3-pali@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org # 7fbcb5da81 ("PCI: aardvark: Don't rely on jiffies while holding spinlock")
There is an issue that when PCIe switch is connected to an Armada 3700
board, there will be lots of warnings about PIO errors when reading the
config space. According to Aardvark PIO read and write sequence in HW
specification, the current way to check PIO status has the following
issues:
1) For PIO read operation, it reports the error message, which should be
avoided according to HW specification.
2) For PIO read and write operations, it only checks PIO operation complete
status, which is not enough, and error status should also be checked.
This patch aligns the code with Aardvark PIO read and write sequence in HW
specification on PIO status check and fix the warnings when reading config
space.
[pali: Fix CRS handling when CRSSVE is not enabled]
Link: https://lore.kernel.org/r/20210722144041.12661-2-pali@kernel.org
Tested-by: Victor Gu <xigu@marvell.com>
Signed-off-by: Evan Wang <xswang@marvell.com>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Victor Gu <xigu@marvell.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org # b1bd571447 ("PCI: aardvark: Indicate error in 'val' when config read fails")
Wherever possible, replace constructs that match either
generic_handle_irq(irq_find_mapping()) or
generic_handle_irq(irq_linear_revmap()) to a single call to
generic_handle_domain_irq().
Link: https://lore.kernel.org/r/20210802162630.2219813-4-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Marvell Armada 3700 Functional Errata, Guidelines, and Restrictions
document describes in erratum 4.1 PCIe value of vendor ID (Ref #: 243):
The readback value of VEND_ID (RD0070000h [15:0]) is 1B4Bh, while it
should read 11ABh.
The firmware can write the correct value, 11ABh, through VEND_ID
(RD0076044h [15:0]).
Implement this workaround in aardvark driver for both PCI vendor id and PCI
subsystem vendor id.
This change affects and fixes PCI vendor id of emulated PCIe root bridge.
After this change emulated PCIe root bridge has correct vendor id.
Link: https://lore.kernel.org/r/20210624222621.4776-5-pali@kernel.org
Fixes: 8a3ebd8de3 ("PCI: aardvark: Implement emulated root PCI bridge config space")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org
PIO_NON_POSTED_REQ for PIO_STAT register is incorrectly defined. Bit 10 in
register PIO_STAT indicates the response is to a non-posted request.
Link: https://lore.kernel.org/r/20210624213345.3617-2-pali@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org
Trying to start a new PIO transfer by writing value 0 in PIO_START register
when previous transfer has not yet completed (which is indicated by value 1
in PIO_START) causes an External Abort on CPU, which results in kernel
panic:
SError Interrupt on CPU0, code 0xbf000002 -- SError
Kernel panic - not syncing: Asynchronous SError Interrupt
To prevent kernel panic, it is required to reject a new PIO transfer when
previous one has not finished yet.
If previous PIO transfer is not finished yet, the kernel may issue a new
PIO request only if the previous PIO transfer timed out.
In the past the root cause of this issue was incorrectly identified (as it
often happens during link retraining or after link down event) and special
hack was implemented in Trusted Firmware to catch all SError events in EL3,
to ignore errors with code 0xbf000002 and not forwarding any other errors
to kernel and instead throw panic from EL3 Trusted Firmware handler.
Links to discussion and patches about this issue:
https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/commit/?id=3c7dcdac5c50https://lore.kernel.org/linux-pci/20190316161243.29517-1-repk@triplefau.lt/https://lore.kernel.org/linux-pci/971be151d24312cc533989a64bd454b4@www.loen.fr/https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/1541
But the real cause was the fact that during link retraining or after link
down event the PIO transfer may take longer time, up to the 1.44s until it
times out. This increased probability that a new PIO transfer would be
issued by kernel while previous one has not finished yet.
After applying this change into the kernel, it is possible to revert the
mentioned TF-A hack and SError events do not have to be caught in TF-A EL3.
Link: https://lore.kernel.org/r/20210608203655.31228-1-pali@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org # 7fbcb5da81 ("PCI: aardvark: Don't rely on jiffies while holding spinlock")
- Update comment about delay before link training (Pali Rohár)
* remotes/lorenzo/pci/aardvark:
PCI: aardvark: Update comment about disabling link training
Add ECAM-related constants to provide a set of standard constants
defining memory address shift values to the byte-level address that can
be used to access the PCI Express Configuration Space, and then move
native PCI Express controller drivers to use the newly introduced
definitions retiring driver-specific ones.
Refactor pci_ecam_map_bus() function to use newly added constants so
that limits to the bus, device function and offset (now limited to 4K as
per the specification) are in place to prevent the defective or
malicious caller from supplying incorrect configuration offset and thus
targeting the wrong device when accessing extended configuration space.
This refactor also allows for the ".bus_shift" initialisers to be
dropped when the user is not using a custom value as a default value
will be used as per the PCI Express Specification.
Thanks to Qian Cai <qcai@redhat.com>, Michael Walle <michael@walle.cc>,
and Vladimir Oltean <olteanv@gmail.com> for reporting a pci_ecam_create()
issue with .bus_shift and to Vladimir for proposing the fix.
[bhelgaas: incorporate Vladimir's fix, update commit log]
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20201129230743.3006978-2-kw@linux.com
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jon Derrick <jonathan.derrick@intel.com>
Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
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 <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Old ATF automatically power on pcie phy and does not provide SMC call for
phy power on functionality which leads to aardvark initialization failure:
[ 0.330134] mvebu-a3700-comphy d0018300.phy: unsupported SMC call, try updating your firmware
[ 0.338846] phy phy-d0018300.phy.1: phy poweron failed --> -95
[ 0.344753] advk-pcie d0070000.pcie: Failed to initialize PHY (-95)
[ 0.351160] advk-pcie: probe of d0070000.pcie failed with error -95
This patch fixes above failure by ignoring 'not supported' error in
aardvark driver. In this case it is expected that phy is already power on.
Tested-by: Tomasz Maciej Nowak <tmn505@gmail.com>
Link: https://lore.kernel.org/r/20200902144344.16684-3-pali@kernel.org
Fixes: 366697018c ("PCI: aardvark: Add PHY support")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: <stable@vger.kernel.org> # 5.8+: ea17a0f153: phy: marvell: comphy: Convert internal SMCC firmware return codes to errno
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 <marek.behun@nic.cz>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Providing driver's 'remove' function allows kernel to bind and unbind devices
from aardvark driver. It also allows to build aardvark driver as a module.
Compiling aardvark as a module simplifies development and debugging of
this driver as it can be reloaded at runtime without the need to reboot
to new kernel.
Link: https://lore.kernel.org/r/20200907111038.5811-5-pali@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
Include linux/gpio/consumer.h instead of linux/gpio.h, as is said in the
latter file.
This was reported by kernel test bot when compiling for s390.
drivers/pci/controller/pci-aardvark.c:350:2: error: implicit declaration of function 'gpiod_set_value_cansleep' [-Werror,-Wimplicit-function-declaration]
drivers/pci/controller/pci-aardvark.c:1074:21: error: implicit declaration of function 'devm_gpiod_get_from_of_node' [-Werror,-Wimplicit-function-declaration]
drivers/pci/controller/pci-aardvark.c:1076:14: error: use of undeclared identifier 'GPIOD_OUT_LOW'
Link: https://lore.kernel.org/r/202006211118.LxtENQfl%25lkp@intel.com
Link: https://lore.kernel.org/r/20200907111038.5811-2-pali@kernel.org
Fixes: 5169a9851d ("PCI: aardvark: Issue PERST via GPIO")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
- Use pci_host_bridge.windows list directly instead of splicing in a
temporary list for cadence, mvebu, host-common (Rob Herring)
- Use pci_host_probe() instead of open-coding all the pieces for altera,
brcmstb, iproc, mobiveil, rcar, rockchip, tegra, v3, versatile, xgene,
xilinx, xilinx-nwl (Rob Herring)
- Convert to devm_platform_ioremap_resource_byname() instead of open-coding
platform_get_resource_byname() and devm_ioremap_resource() for altera,
cadence, mediatek, rockchip, tegra, xgene (Dejin Zheng)
- Convert to devm_platform_ioremap_resource() instead of open-coding
platform_get_resource() and devm_ioremap_resource() for aardvark,
brcmstb, exynos, ftpci100, versatile (Dejin Zheng)
- Remove redundant error messages from devm_pci_remap_cfg_resource()
callers (Dejin Zheng)
- Drop useless PCI_ENABLE_PROC_DOMAINS from versatile driver (Rob Herring)
- Default host bridge parent device to the platform device (Rob Herring)
- Drop unnecessary zeroing of host bridge fields (Rob Herring)
- Use pci_is_root_bus() instead of tracking root bus number separately in
aardvark, designware (imx6, keystone, designware-host), mobiveil,
xilinx-nwl, xilinx, rockchip, rcar (Rob Herring)
- Set host bridge bus number in pci_scan_root_bus_bridge() instead of each
driver for aardvark, designware-host, host-common, mediatek, rcar, tegra,
v3-semi (Rob Herring)
- Use bridge resources instead of parsing DT 'ranges' again for cadence
(Rob Herring)
- Remove private bus number and range from cadence (Rob Herring)
- Use devm_pci_alloc_host_bridge() to simplify rcar (Rob Herring)
- Use struct pci_host_bridge.windows list directly rather than a temporary
(Rob Herring)
- Reduce OF "missing non-prefetchable window" from error to warning message
(Rob Herring)
- Convert rcar-gen2 from old Arm-specific pci_common_init_dev() to new
arch-independent interfaces (Rob Herring)
- Move DT resource setup into devm_pci_alloc_host_bridge() (Rob Herring)
- Set bridge map_irq and swizzle_irq to default functions; drivers that
don't support legacy IRQs (iproc) need to undo this (Rob Herring)
* pci/host-probe-refactor:
PCI: Set bridge map_irq and swizzle_irq to default functions
PCI: Move DT resource setup into devm_pci_alloc_host_bridge()
PCI: rcar-gen2: Convert to use modern host bridge probe functions
PCI: of: Reduce missing non-prefetchable memory region to a warning
PCI: rcar: Use struct pci_host_bridge.windows list directly
PCI: rcar: Use devm_pci_alloc_host_bridge()
PCI: cadence: Remove private bus number and range storage
PCI: cadence: Use bridge resources for outbound window setup
PCI: Move setting pci_host_bridge.busnr out of host drivers
PCI: rcar: Use pci_is_root_bus() to check if bus is root bus
PCI: rockchip: Use pci_is_root_bus() to check if bus is root bus
PCI: xilinx: Use pci_is_root_bus() to check if bus is root bus
PCI: xilinx-nwl: Use pci_is_root_bus() to check if bus is root bus
PCI: mobiveil: Use pci_is_root_bus() to check if bus is root bus
PCI: designware: Use pci_is_root_bus() to check if bus is root bus
PCI: aardvark: Use pci_is_root_bus() to check if bus is root bus
PCI: Drop unnecessary zeroing of bridge fields
PCI: Set default bridge parent device
PCI: versatile: Drop flag PCI_ENABLE_PROC_DOMAINS
PCI: controller: Remove duplicate error message
PCI: controller: Convert to devm_platform_ioremap_resource()
PCI: controller: Convert to devm_platform_ioremap_resource_byname()
PCI: xilinx: Use pci_host_probe() to register host
PCI: xilinx-nwl: Use pci_host_probe() to register host
PCI: rockchip: Use pci_host_probe() to register host
PCI: rcar: Use pci_host_probe() to register host
PCI: iproc: Use pci_host_probe() to register host
PCI: altera: Use pci_host_probe() to register host
PCI: xgene: Use pci_host_probe() to register host
PCI: versatile: Use pci_host_probe() to register host
PCI: v3: Use pci_host_probe() to register host
PCI: tegra: Use pci_host_probe() to register host
PCI: mobiveil: Use pci_host_probe() to register host
PCI: brcmstb: Use pci_host_probe() to register host
PCI: host-common: Use struct pci_host_bridge.windows list directly
PCI: mvebu: Use struct pci_host_bridge.windows list directly
PCI: cadence: Use struct pci_host_bridge.windows list directly
# Conflicts:
# drivers/pci/controller/cadence/pcie-cadence-host.c
The majority of DT based host drivers use the default .map_irq() and
.swizzle_irq() functions, so let's initialize the function pointers to
the default and drop setting them in the host drivers.
Drivers like iProc which don't support legacy interrupts need to set
.map_irq() back to NULL.
Link: https://lore.kernel.org/r/20200722022514.1283916-20-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Now that pci_parse_request_of_pci_ranges() callers just setup
pci_host_bridge.windows and dma_ranges directly and don't need the bus
range returned, we can just initialize them when allocating the
pci_host_bridge struct.
With this, pci_parse_request_of_pci_ranges() becomes a static function.
Link: https://lore.kernel.org/r/20200722022514.1283916-19-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Most host drivers only parse the DT bus range to set the root bus number
in pci_host_bridge.busnr. The ones that don't set busnr are buggy in
that they ignore what's in DT. Let's set busnr in pci_scan_root_bus_bridge()
where we already check for the bus resource and remove setting it in
host drivers.
Link: https://lore.kernel.org/r/20200722022514.1283916-12-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Jingoo Han <jingoohan1@gmail.com>
Cc: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Will Deacon <will@kernel.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Ryder Lee <ryder.lee@mediatek.com>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: linux-tegra@vger.kernel.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-renesas-soc@vger.kernel.org
Use pci_is_root_bus() rather than tracking the root bus number to
determine if the bus is the root bus or not. This removes storing
duplicated data as well as the need for the host bridge driver to have
to care about the bus numbers in most cases.
Link: https://lore.kernel.org/r/20200722022514.1283916-5-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
The struct pci_host_bridge is 0 initialized when allocated, so there's
no need to explicitly set fields to 0.
Link: https://lore.kernel.org/r/20200722022514.1283916-4-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
The host bridge's parent device is always the platform device. As we
already have a pointer to it in the devres functions, let's initialize
the parent device. Drivers can still override the parent if desired.
Link: https://lore.kernel.org/r/20200722022514.1283916-3-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
When there is no PCIe card connected and advk_pcie_rd_conf() or
advk_pcie_wr_conf() is called for PCI bus which doesn't belong to emulated
root bridge, the aardvark driver throws the following error message:
advk-pcie d0070000.pcie: config read/write timed out
Obviously accessing PCIe registers of disconnected card is not possible.
Extend check in advk_pcie_valid_device() function for validating
availability of PCIe bus. If PCIe link is down, then the device is marked
as Not Found and the driver does not try to access these registers.
This is just an optimization to prevent accessing PCIe registers when card
is disconnected. Trying to access PCIe registers of disconnected card does
not cause any crash, kernel just needs to wait for a timeout. So if card
disappear immediately after checking for PCIe link (before accessing PCIe
registers), it does not cause any problems.
Link: https://lore.kernel.org/r/20200702083036.12230-1-pali@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Use devm_platform_ioremap_resource() to simplify the code, since t
contains platform_get_resource() and devm_ioremap_resource() calls
respectively.
Link: https://lore.kernel.org/r/20200708155614.308-1-zhengdejin5@gmail.com
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Most callers of config read do not check for return value. But most of the
ones that do, checks for error indication in 'val' variable.
This patch updates error handling in advk_pcie_rd_conf() function. If PIO
transfer fails then 'val' variable is set to 0xffffffff which indicates
failture.
Link: https://lore.kernel.org/r/20200528162604.GA323482@bjorn-Precision-5520
Link: https://lore.kernel.org/r/20200601130315.18895-1-pali@kernel.org
Reported-by: Bjorn Helgaas <helgaas@kernel.org>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
- Train link immediately after enabling link training to avoid issues
with Compex WLE900VX and Turris MOX devices (Pali Rohár)
- Remove ASPM config and let the PCI core do it (Pali Rohár)
- Interpret zero 'max-link-speed' value as invalid (Pali Rohár)
- Respect the 'max-link-speed' property and improve link training (Marek
Behún)
- Issue PERST via GPIO (Pali Rohár)
- Add PHY support (Marek Behún)
- Use standard PCIe capability macros (Pali Rohár)
- Document new 'max-link-speed', 'phys', and 'reset-gpios' properties
(Marek Behún)
* remotes/lorenzo/pci/aardvark:
dt-bindings: PCI: aardvark: Describe new properties
PCI: aardvark: Replace custom macros by standard linux/pci_regs.h macros
PCI: aardvark: Add PHY support
PCI: aardvark: Add FIXME comment for PCIE_CORE_CMD_STATUS_REG access
PCI: aardvark: Issue PERST via GPIO
PCI: aardvark: Improve link training
PCI: of: Zero max-link-speed value is invalid
PCI: aardvark: Don't blindly enable ASPM L0s and don't write to read-only register
PCI: aardvark: Train link immediately after enabling training
PCI-E capability macros are already defined in linux/pci_regs.h.
Remove their reimplementation in pcie-aardvark.
Link: https://lore.kernel.org/r/20200430080625.26070-9-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>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
With recent proposed changes for U-Boot it is possible that bootloader
won't initialize the PHY for this controller (currently the PHY is
initialized regardless whether PCI is used in U-Boot, but with these
proposed changes the PHY is initialized only on request).
Since the mvebu-a3700-comphy driver by Miquèl Raynal supports enabling
PCIe PHY, and since Linux' functionality should be independent on what
bootloader did, add code for enabling generic PHY if found in device OF
node.
The mvebu-a3700-comphy driver does PHY powering via SMC calls to ARM
Trusted Firmware. The corresponding code in ARM Trusted Firmware skips
one register write which U-Boot does not: step 7 ("Enable TX"), see [1].
Instead ARM Trusted Firmware expects PCIe driver to do this step,
probably because the register is in PCIe controller address space,
instead of PHY address space. We therefore add this step into the
advk_pcie_setup_hw function.
[1] https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/tree/drivers/marvell/comphy/phy-comphy-3700.c?h=v2.3-rc2#n836
Link: https://lore.kernel.org/r/20200430080625.26070-8-pali@kernel.org
Tested-by: Tomasz Maciej Nowak <tmn505@gmail.com>
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>
Cc: Miquèl Raynal <miquel.raynal@bootlin.com>
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>
