Previously pci_enable_link_state(PCIE_LINK_STATE_L1_1) enabled only
ASPM_STATE_L1_1 and did not enable ASPM_STATE_L1. The L1.1 state only
works when L1 is enabled, so enable ASPM_STATE_L1 in addition, and do the
same for L1.2.
The only current caller is vmd_pm_enable_quirk(), which enables *all* ASPM
states, so this should have no functional effect.
[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20230504111301.229358-4-ajayagarwal@google.com
Signed-off-by: Ajay Agarwal <ajayagarwal@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously pci_enable_link_state(PCIE_LINK_STATE_L1) enabled L1SS as well
as L1. Enable only ASPM_STATE_L1 when the caller enables L1.
The only current caller is vmd_pm_enable_quirk(), which enables *all* ASPM
states, so this should have no functional effect.
[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20230504111301.229358-3-ajayagarwal@google.com
Signed-off-by: Ajay Agarwal <ajayagarwal@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Previously pci_disable_link_state(PCIE_LINK_STATE_L1) disabled L1SS as well
as L1. This is unnecessary since pcie_config_aspm_link() takes care that
L1SS is not enabled if L1 is disabled.
Disable only ASPM_STATE_L1 when the caller disables L1. No functional
changes intended.
This is consistent with aspm_attr_store_common(), which disables only L1,
not L1SS, when L1 is disabled via the sysfs "l1_aspm" file.
[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20230504111301.229358-2-ajayagarwal@google.com
Signed-off-by: Ajay Agarwal <ajayagarwal@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Struct pcie_link_state->downstream is a pointer to the pci_dev of function
0. Previously we retained that pointer when removing function 0, and
subsequent ASPM policy changes dereferenced it, resulting in a
use-after-free warning from KASAN, e.g.:
# echo 1 > /sys/bus/pci/devices/0000:03:00.0/remove
# echo powersave > /sys/module/pcie_aspm/parameters/policy
BUG: KASAN: slab-use-after-free in pcie_config_aspm_link+0x42d/0x500
Call Trace:
kasan_report+0xae/0xe0
pcie_config_aspm_link+0x42d/0x500
pcie_aspm_set_policy+0x8e/0x1a0
param_attr_store+0x162/0x2c0
module_attr_store+0x3e/0x80
PCIe spec r6.0, sec 7.5.3.7, recommends that software program the same ASPM
Control value in all functions of multi-function devices.
Disable ASPM and free the pcie_link_state when any child function is
removed so we can discard the dangling pcie_link_state->downstream pointer
and maintain the same ASPM Control configuration for all functions.
[bhelgaas: commit log and comment]
Debugged-by: Zongquan Qin <qinzongquan@sangfor.com.cn>
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Fixes: b5a0a9b59c ("PCI/ASPM: Read and set up L1 substate capabilities")
Link: https://lore.kernel.org/r/20230507034057.20970-1-dinghui@sangfor.com.cn
Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
-----BEGIN PGP SIGNATURE-----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=/y4d
-----END PGP SIGNATURE-----
Merge tag 'pci-v6.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
Pull PCI updates from Bjorn Helgaas:
"Enumeration:
- Rework portdrv shutdown so it disables interrupts but doesn't
disable bus mastering, which leads to hangs on Loongson LS7A
- Add mechanism to prevent Max_Read_Request_Size (MRRS) increases,
again to avoid hardware issues on Loongson LS7A (and likely other
devices based on DesignWare IP)
- Ignore devices with a firmware (DT or ACPI) node that says the
device is disabled
Resource management:
- Distribute spare resources to unconfigured hotplug bridges at
boot-time (not just when hot-adding such a bridge), which makes
hot-adding devices to docks work better. Tried this in v6.1 but had
to revert for regressions, so try again
- Fix root bus issue that dropped resources that happened to end
at 0, e.g., [bus 00]
PCI device hotplug:
- Remove device locking when marking device as disconnected so this
doesn't have to wait for concurrent driver bind/unbind to complete
- Quirk more Qualcomm bridges that don't fully implement the PCIe
Slot Status 'Command Completed' bit
Power management:
- Account for _S0W of the target bridge in acpi_pci_bridge_d3() so we
don't miss hot-add notifications for USB4 docks, Thunderbolt, etc
Reset:
- Observe delay after reset, e.g., resuming from system sleep,
regardless of whether a bridge can suspend to D3cold at runtime
- Wait for secondary bus to become ready after a bridge reset
Virtualization:
- Avoid FLR on some AMD FCH AHCI adapters where it doesn't work
- Allow independent IOMMU groups for some Wangxun NICs that prevent
peer-to-peer transactions but don't advertise an ACS Capability
Error handling:
- Configure End-to-End-CRC (ECRC) only if Linux owns the AER
Capability
- Remove redundant Device Control Error Reporting Enable in the AER
service driver since this is already done for all devices during
enumeration
ASPM:
- Add pci_enable_link_state() interface to allow drivers to enable
ASPM link state
Endpoint framework:
- Move dra7xx and tegra194 linkup processing from hard IRQ to
threaded IRQ handler
- Add a separate lock for endpoint controller list of endpoint
function drivers to prevent deadlock in callbacks
- Pass events from endpoint controller to endpoint function drivers
via callbacks instead of notifiers
Synopsys DesignWare eDMA controller driver (acked by Vinod):
- Fix CPU vs PCI address issues
- Fix source vs destination address issues
- Fix issues with interleaved transfer semantics
- Fix channel count initialization issue (issue still exists in
several other drivers)
- Clean up and improve debugfs usage so it will work on platforms
with several eDMA devices
Baikal T-1 PCIe controller driver:
- Set a 64-bit DMA mask
Freescale i.MX6 PCIe controller driver:
- Add i.MX8MM, i.MX8MQ, i.MX8MP endpoint mode DT binding and driver
support
Intel VMD host bridge driver:
- Add quirk to configure PCIe ASPM and LTR. This is normally done by
BIOS, and will be for future products
Marvell MVEBU PCIe controller driver:
- Mark this driver as broken in Kconfig since bugs prevent its daily
usage
MediaTek MT7621 PCIe controller driver:
- Delay PHY port initialization to improve boot reliability for ZBT
WE1326, ZBT WF3526-P, and some Netgear models
Qualcomm PCIe controller driver:
- Add MSM8998 DT compatible string
- Unify MSM8996 and MSM8998 clock orderings
- Add SM8350 DT binding and driver support
- Add IPQ8074 Gen3 DT binding and driver support
- Correct qcom,perst-regs in DT binding
- Add qcom_pcie_host_deinit() so the PHY is powered off and
regulators and clocks are disabled on late host-init errors
Socionext UniPhier Pro5 controller driver:
- Clean up uniphier-ep reg, clocks, resets, and their names in DT
binding
Synopsys DesignWare PCIe controller driver:
- Restrict coherent DMA mask to 32 bits for MSI, but allow controller
drivers to set 64-bit streaming DMA mask
- Add eDMA engine support in both Root Port and Endpoint controllers
Miscellaneous:
- Remove MODULE_LICENSE from boolean drivers so they don't look like
modules so modprobe can complain about them"
* tag 'pci-v6.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (86 commits)
PCI: dwc: Add Root Port and Endpoint controller eDMA engine support
PCI: bt1: Set 64-bit DMA mask
PCI: dwc: Restrict only coherent DMA mask for MSI address allocation
dmaengine: dw-edma: Prepare dw_edma_probe() for builtin callers
dmaengine: dw-edma: Depend on DW_EDMA instead of selecting it
dmaengine: dw-edma: Add mem-mapped LL-entries support
PCI: Remove MODULE_LICENSE so boolean drivers don't look like modules
PCI: hv: Drop duplicate PCI_MSI dependency
PCI/P2PDMA: Annotate RCU dereference
PCI/sysfs: Constify struct kobj_type pci_slot_ktype
PCI: hotplug: Allow marking devices as disconnected during bind/unbind
PCI: pciehp: Add Qualcomm quirk for Command Completed erratum
PCI: qcom: Add IPQ8074 Gen3 port support
dt-bindings: PCI: qcom: Add IPQ8074 Gen3 port
dt-bindings: PCI: qcom: Sort compatibles alphabetically
PCI: qcom: Fix host-init error handling
PCI: qcom: Add SM8350 support
dt-bindings: PCI: qcom: Add SM8350
dt-bindings: PCI: qcom-ep: Correct qcom,perst-regs
dt-bindings: PCI: qcom: Unify MSM8996 and MSM8998 clock order
...
This reverts commit 5e85eba6f5.
Thomas Witt reported that 5e85eba6f5 ("PCI/ASPM: Refactor L1 PM Substates
Control Register programming") broke suspend/resume on a Tuxedo
Infinitybook S 14 v5, which seems to use a Clevo L140CU Mainboard.
The main symptom is:
iwlwifi 0000:02:00.0: Unable to change power state from D3hot to D0, device inaccessible
nvme 0000:03:00.0: Unable to change power state from D3hot to D0, device inaccessible
and the machine is only partially usable after resume. It can't run dmesg
and can't do a clean reboot. This happens on every suspend/resume cycle.
Revert 5e85eba6f5 until we can figure out the root cause.
Fixes: 5e85eba6f5 ("PCI/ASPM: Refactor L1 PM Substates Control Register programming")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216877
Reported-by: Thomas Witt <kernel@witt.link>
Tested-by: Thomas Witt <kernel@witt.link>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org # v6.1+
Cc: Vidya Sagar <vidyas@nvidia.com>
This reverts commit 4ff116d0d5.
Tasev Nikola and Mark Enriquez reported that resume from suspend was broken
in v6.1-rc1. Tasev bisected to a47126ec29 ("PCI/PTM: Cache PTM
Capability offset"), but we can't figure out how that could be related.
Mark saw the same symptoms and bisected to 4ff116d0d5 ("PCI/ASPM: Save L1
PM Substates Capability for suspend/resume"), which does have a connection:
it restores L1 Substates configuration while ASPM L1 may be enabled:
pci_restore_state
pci_restore_aspm_l1ss_state
aspm_program_l1ss
pci_write_config_dword(PCI_L1SS_CTL1, ctl1) # L1SS restore
pci_restore_pcie_state
pcie_capability_write_word(PCI_EXP_LNKCTL, cap[i++]) # L1 restore
which is a problem because PCIe r6.0, sec 5.5.4, requires that:
If setting either or both of the enable bits for ASPM L1 PM
Substates, both ports must be configured as described in this
section while ASPM L1 is disabled.
Separately, Thomas Witt reported that 5e85eba6f5 ("PCI/ASPM: Refactor L1
PM Substates Control Register programming") broke suspend/resume, and it
depends on 4ff116d0d5.
Revert 4ff116d0d5 ("PCI/ASPM: Save L1 PM Substates Capability for
suspend/resume") to fix the resume issue and enable revert of 5e85eba6f5
to fix the issue Thomas reported.
Note that reverting 4ff116d0d5 means L1 Substates config may be lost on
suspend/resume. As far as we know the system will use more power but will
still *work* correctly.
Fixes: 4ff116d0d5 ("PCI/ASPM: Save L1 PM Substates Capability for suspend/resume")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216782
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216877
Reported-by: Tasev Nikola <tasev.stefanoska@skynet.be>
Reported-by: Mark Enriquez <enriquezmark36@gmail.com>
Reported-by: Thomas Witt <kernel@witt.link>
Tested-by: Mark Enriquez <enriquezmark36@gmail.com>
Tested-by: Thomas Witt <kernel@witt.link>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org # v6.1+
Cc: Vidya Sagar <vidyas@nvidia.com>
Add pci_enable_link_state() to allow devices to change the default BIOS
configured states. Clears the BIOS default settings then sets the new
states and reconfigures the link under the semaphore. Also add
PCIE_LINK_STATE_ALL macro for convenience for callers that want to enable
all link states.
Link: https://lore.kernel.org/r/20230120031522.2304439-2-david.e.box@linux.intel.com
Signed-off-by: Michael Bottini <michael.a.bottini@linux.intel.com>
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
80d7d7a904 ("PCI/ASPM: Calculate LTR_L1.2_THRESHOLD from device
characteristics") replaced a fixed value (163840ns) with one computed from
T_POWER_OFF, Common_Mode_Restore_Time, etc., but it encoded the
LTR_L1.2_THRESHOLD value incorrectly.
This is especially a problem for small thresholds, e.g., 63ns fell into the
"threshold_ns < 1024" case and was encoded as 32ns:
LTR_L1.2_THRESHOLD_Scale = 1 (multiplier is 32ns)
LTR_L1.2_THRESHOLD_Value = 63 >> 5 = 1
LTR_L1.2_THRESHOLD = multiplier * value = 32ns * 1 = 32ns
Correct the algorithm to encode all times of 1023ns (0x3ff) or smaller
exactly and larger times conservatively (the encoded threshold is never
smaller than was requested). This reduces the chance of entering L1.2
when the device can't tolerate the exit latency.
Fixes: 80d7d7a904 ("PCI/ASPM: Calculate LTR_L1.2_THRESHOLD from device characteristics")
Link: https://lore.kernel.org/r/20221005025809.2247547-4-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
187f91db82 ("PCI/ASPM: Remove struct aspm_register_info.l1ss_cap")
inadvertently removed a check for existence of the L1 PM Substates (L1SS)
Capability before reading it.
If there is no L1SS Capability, this means we mistakenly read PCI_COMMAND
and PCI_STATUS (config address 0x04) and interpret that as the PCI_L1SS_CAP
register, so we may incorrectly configure L1SS.
Make sure the L1SS Capability exists before trying to read it.
Fixes: 187f91db82 ("PCI/ASPM: Remove struct aspm_register_info.l1ss_cap")
Link: https://lore.kernel.org/r/20221005025809.2247547-3-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Previously the L1 PM Substates Control Registers (CTL1 and CTL2) weren't
saved and restored during suspend/resume leading to the L1 PM Substates
configuration being lost post-resume.
Save the L1 PM Substates Control Registers so that the configuration is
retained post-resume.
[bhelgaas: drop pci_is_pcie() testing; we can rely on pci_configure_ltr()
having already done that]
Link: https://lore.kernel.org/r/20220913131822.16557-3-vidyas@nvidia.com
Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
pcie_aspm_support_enabled() is used only by the acpi/pci_root.c driver,
which cannot be built as a module, so it does not need to be exported.
Unexport it.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
pcie_aspm_pm_state_change() was introduced at the inception of PCIe ASPM
code, but it can cause some issues. For instance, when ASPM config is
changed via sysfs, those changes won't persist across power state change
because pcie_aspm_pm_state_change() overwrites them.
Also, if the driver restores L1SS [1] after system resume, the restored
state will also be overwritten by pcie_aspm_pm_state_change().
Remove pcie_aspm_pm_state_change(). If there's any hardware that really
needs it to function, a quirk can be used instead.
[1] https://lore.kernel.org/linux-pci/20220201123536.12962-1-vidyas@nvidia.com/
Link: https://lore.kernel.org/r/20220509073639.2048236-1-kai.heng.feng@canonical.com
[bhelgaas: remove additional pcie_aspm_pm_state_change() call in
pci_set_low_power_state(), added by
10aa5377fc ("PCI/PM: Split pci_raw_set_power_state()") and moved by
7957d20145 ("PCI/PM: Relocate pci_set_low_power_state()")]
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
- Use pci_find_vsec_capability() instead of open-coding it (Andy
Shevchenko)
- Convert pci_dev_present() stub from macro to static inline to avoid
'unused variable' errors (Hans de Goede)
- Convert sysfs slot attributes from default_attrs to default_groups (Greg
Kroah-Hartman)
- Use DWORD accesses for LTR, L1 SS to avoid BayHub OZ711LV2 erratum (Rajat
Jain)
- Remove unnecessary initialization of static variables (Longji Guo)
* pci/enumeration:
x86/PCI: Remove initialization of static variables to false
PCI: Use DWORD accesses for LTR, L1 SS to avoid erratum
PCI/sysfs: Use default_groups in kobj_type for slot attrs
PCI: Convert pci_dev_present() stub to static inline
PCI: Use pci_find_vsec_capability() when looking for TBT devices
Some devices have an erratum such that they only support DWORD accesses to
some registers. E.g., this Bayhub O2 device ([VID:DID] = [0x1217:0x8621])
only supports DWORD accesses to LTR latency registers and L1 PM substates
control registers:
https://github.com/rajatxjain/public_shared/blob/main/OZ711LV2_appnote.pdf
The L1 PM substate control registers are DWORD sized, and hence their
access in the kernel is already DWORD sized, so we don't need to do
anything for them.
However, the LTR registers being WORD sized, are in need of a solution.
Convert the WORD sized accesses to these registers into DWORD sized
accesses while saving and restoring them.
Link: https://lore.kernel.org/r/20211222012105.3438916-1-rajatja@google.com
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The struct aspm_latency is now used only inside pcie_aspm_check_latency().
Replace struct aspm_latency variables with u32 variables and remove struct
aspm_latency.
Link: https://lore.kernel.org/r/20211119193732.12343-5-refactormyself@gmail.com
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Previously we calculated the device's acceptable L0s and L1 exit latencies
in pcie_aspm_cap_init() and cached them in struct pcie_link_state.
These values are only used in pcie_aspm_check_latency() where they are
compared with the actual exit latencies of the link. This path is used
when removing or changing the D state of the device, so it's relatively low
frequency.
To reduce the amount of per-link data we store, remove the acceptable[]
arrays from struct pcie_link_state and calculate them directly from the
already-cached Device Capabilities register when needed.
[bhelgaas: use endpoint->devcap instead of reading it again]
Link: https://lore.kernel.org/r/20211119193732.12343-4-refactormyself@gmail.com
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we calculated the upstream and downstream L0s and L1 exit
latencies of the link in pcie_aspm_cap_init() and cached them in struct
pcie_link_state.latency_*.
These values are only used in pcie_aspm_check_latency() where they are
compared with the acceptable latencies on the link. This path is used when
removing or changing the D state of the device, so it's relatively low
frequency.
To reduce the amount of per-link data we store, remove the latency_*
entries from struct pcie_link_state and calculate the latencies directly
where they are needed.
Link: https://lore.kernel.org/r/20211119193732.12343-3-refactormyself@gmail.com
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Move pci_function_0() earlier so we can use it from other functions.
Link: https://lore.kernel.org/r/20211119193732.12343-2-refactormyself@gmail.com
Signed-off-by: Bolarinwa O. Saheed <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
strtobool() is a wrapper around kstrtobool() that has been added for
backward compatibility.
There is no reason to use the old API, so use kstrtobool() directly.
Related: ef95159907 ("lib: move strtobool() to kstrtobool()")
Link: https://lore.kernel.org/r/20210915230127.2495723-3-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The sysfs_emit() and sysfs_emit_at() functions were introduced to make
it less ambiguous which function is preferred when writing to the output
buffer in a device attribute's "show" callback [1].
Convert the PCI sysfs object "show" functions from sprintf(), snprintf()
and scnprintf() to sysfs_emit() and sysfs_emit_at() accordingly, as the
latter is aware of the PAGE_SIZE buffer and correctly returns the number
of bytes written into the buffer.
No functional change intended.
[1] Documentation/filesystems/sysfs.rst
Related commit: ad025f8e46 ("PCI/sysfs: Use sysfs_emit() and
sysfs_emit_at() in "show" functions").
Link: https://lore.kernel.org/r/20210603000112.703037-2-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Previously ASPM L1 Substates control registers (CTL1 and CTL2) weren't
saved and restored during suspend/resume leading to L1 Substates
configuration being lost post-resume.
Save the L1 Substates control registers so that the configuration is
retained post-resume.
Link: https://lore.kernel.org/r/20201024190442.871-1-vidyas@nvidia.com
Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we computed L1.2 parameters in the enumeration path, saved them
in struct pcie_link_state.l1ss, and programmed them into the devices
whenever we enabled or disabled L1.2 on the link. But these parameters are
constant and don't need to be updated when enabling/disabling L1.2.
Compute and program the L1.2 parameters once during enumeration and remove
the struct pcie_link_state.l1ss member. No functional change intended.
[bhelgaas: rework to program L1.2 parameters during enumeration]
Link: https://lore.kernel.org/r/20201015193039.12585-13-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we stored the L1SS Capabilities value in the struct
aspm_register_info.
We only need this information in one place, so read it there and remove
struct aspm_register_info completely, since it's now empty. No functional
change intended.
[bhelgaas: split up, don't cache l1ss_cap in pci_dev]
Link: https://lore.kernel.org/r/20201015193039.12585-12-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
aspm_calc_l1ss_info() needs only the L1SS Capabilities. It doesn't need
anything else from struct aspm_register_info, so pass only the Capabilities
value. No functional change intended.
Link: https://lore.kernel.org/r/20201015193039.12585-11-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we stored the L1SS Control 1 register in the struct
aspm_register_info.
We only need this information in one place, so read it there and remove it
from struct aspm_register_info. No functional change intended.
[bhelgaas: split ctl1/ctl2]
Link: https://lore.kernel.org/r/20201015193039.12585-10-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Save the L1 Substates Capability pointer in struct pci_dev. Then we don't
have to keep track of it in the struct aspm_register_info and struct
pcie_link_state, which makes the code easier to read. No functional change
intended.
[bhelgaas: split to a separate patch]
Link: https://lore.kernel.org/r/20201015193039.12585-8-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we stored L0s and L1 Exit Latency information from the Link
Capabilities register in the struct aspm_register_info.
We only need these latencies when we already have the Link Capabilities
values, so use those directly and remove the latencies from struct
aspm_register_info. No functional change intended.
Link: https://lore.kernel.org/r/20201015193039.12585-7-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we stored the "ASPM Control" bits from the Link Control register
in the struct aspm_register_info.
Read PCI_EXP_LNKCTL directly when needed. This means we can use the
PCI_EXP_LNKCTL_ASPM_* bits directly instead of the similar but different
PCIE_LINK_STATE_* bits. No functional change intended.
[bhelgaas: drop get_aspm_enable() and read LNKCTL once directly]
Link: https://lore.kernel.org/r/20201015193039.12585-6-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we stored the "ASPM Support" field from the Link Capabilities
register in the struct aspm_register_info.
Read the Link Capabilities directly when needed and remove it from the
struct aspm_register_info. No functional change intended.
[bhelgaas: remove pci_dev cached copy since LNKCAP isn't truly read-only,
add PCI_EXP_LNKCAP_ASPM_L0S & PCI_EXP_LNKCAP_ASPM_L1, check them directly
instead of adding aspm_support()]
Link: https://lore.kernel.org/r/20201015193039.12585-5-helgaas@kernel.org
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Other users of link->pdev and link->downstream, e.g., pcie_aspm_cap_init(),
pcie_config_aspm_l1ss(), and pcie_config_aspm_link(), use "parent" and
"child" as local names.
Do the same in aspm_calc_l1ss_info() for readability. No functional change
intended.
Link: https://lore.kernel.org/r/20201015193039.12585-4-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
pcie_get_aspm_reg() mostly reads ASPM-related registers, but in some cases
it also updates the value read from PCI_L1SS_CAP based on LTR properties.
Move this update to the point where the value is used to make the code more
readable.
No functional change intended, although previously we could clear
PCI_L1SS_CAP_ASPM_L1_2 for both ends of the link, and now we'll only do it
for the downstream end of a link. This shouldn't matter because we always
test that bit by ANDing l1ss_cap for the upstream and downstream ends.
Link: https://lore.kernel.org/r/20201015193039.12585-3-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
When I cat ASPM parameter 'policy' by sysfs, it displays as follows. Add a
newline for easy reading. Other sysfs attributes already include a
newline.
[root@localhost ~]# cat /sys/module/pcie_aspm/parameters/policy
[default] performance powersave powersupersave [root@localhost ~]#
Fixes: 7d715a6c1a ("PCI: add PCI Express ASPM support")
Link: https://lore.kernel.org/r/1594972765-10404-1-git-send-email-wangxiongfeng2@huawei.com
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
7d715a6c1a ("PCI: add PCI Express ASPM support") added the ability for
Linux to enable ASPM, but for some undocumented reason, it didn't enable
ASPM on links where the downstream component is a PCIe-to-PCI/PCI-X Bridge.
Remove this exclusion so we can enable ASPM on these links.
The Dell OptiPlex 7080 mentioned in the bugzilla has a TI XIO2001
PCIe-to-PCI Bridge. Enabling ASPM on the link leading to it allows the
Intel SoC to enter deeper Package C-states, which is a significant power
savings.
[bhelgaas: commit log]
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=207571
Link: https://lore.kernel.org/r/20200505173423.26968-1-kai.heng.feng@canonical.com
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
When the UEFI/BIOS or bootloader has not initialised a PCIe device we would
get the following message:
kern.warning: pci 0000:00:01.0: ASPM: current common clock configuration is broken, reconfiguring
"warning" and "broken" are slightly misleading. On an embedded system it is
quite possible for the bootloader to avoid configuring PCIe devices if they
are not needed.
Downgrade the message to pci_info() and change "broken" to "inconsistent"
since we fix up the inconsistency in the code immediately following the
message (and emit an error if that fails).
Link: https://lore.kernel.org/r/20200323035530.11569-1-chris.packham@alliedtelesis.co.nz
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
In pcie_config_aspm_l1ss(), we cleared the wrong bits when enabling ASPM L1
Substates. Instead of the L1.x enable bits (PCI_L1SS_CTL1_L1SS_MASK, 0xf), we
cleared the Link Activation Interrupt Enable bit (PCI_L1SS_CAP_L1_PM_SS,
0x10).
Clear the L1.x enable bits before writing the new L1.x configuration.
[bhelgaas: changelog]
Fixes: aeda9adeba ("PCI/ASPM: Configure L1 substate settings")
Link: https://lore.kernel.org/r/1584093227-1292-1-git-send-email-yangyicong@hisilicon.com
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org # v4.11+
Previously, CONFIG_PCIEASPM_DEBUG enabled "link_state" and "clk_ctl" sysfs
files that controlled ASPM. We believe these files were rarely if ever
used.
We recently added sysfs ASPM controls that are always present, so the debug
code is no longer needed. Removing this debug code has been discussed for
quite some time, see e.g. [0].
Remove PCIEASPM_DEBUG and the related code.
[0] https://lore.kernel.org/lkml/20180727202619.GD173328@bhelgaas-glaptop.roam.corp.google.com/
Link: https://lore.kernel.org/r/ec935d8e-c084-3938-f1d1-748617596b25@gmail.com
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Add sysfs attributes to Endpoints and other Upstream Ports to control ASPM,
Clock PM, and L1 PM Substates. The new attributes are:
/sys/devices/pci*/.../link/clkpm
/sys/devices/pci*/.../link/l0s_aspm
/sys/devices/pci*/.../link/l1_aspm
/sys/devices/pci*/.../link/l1_1_aspm
/sys/devices/pci*/.../link/l1_2_aspm
/sys/devices/pci*/.../link/l1_1_pcipm
/sys/devices/pci*/.../link/l1_2_pcipm
An attribute is only visible if both ends of the Link leading to the device
support the state. Writing y/1/on to the file enables the state; n/0/off
disables it.
These attributes can be used to tune the power/performance tradeoff for
individual devices.
[bhelgaas: commit log, rename directory to "link"]
Link: https://lore.kernel.org/r/b1c83f8a-9bf6-eac5-82d0-cf5b90128fbf@gmail.com
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Factor out getting the link associated with a pci_dev and use this helper
where appropriate. In addition this helper will be used in a subsequent
patch of this series.
Link: https://lore.kernel.org/r/19d33770-29de-a9af-4d85-f2b30269d383@gmail.com
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously Clock PM could not be re-enabled after being disabled by
pci_disable_link_state() because clkpm_capable was reset. Change this by
adding a clkpm_disable field similar to aspm_disable.
Link: https://lore.kernel.org/r/4e8a66db-7d53-4a66-c26c-f0037ffaa705@gmail.com
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Add support for disabling states L1.1 and L1.2 to pci_disable_link_state().
Allow separate control of ASPM and PCI PM L1 substates.
Link: https://lore.kernel.org/r/d81f8036-c236-6463-48e7-ebcdcda85bba@gmail.com
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The lifetime of the link_state structure (bridge->link_state) is not the
same as the lifetime of "bridge" itself. The link_state is allocated by
pcie_aspm_init_link_state() after children of the bridge have been
enumerated, and it is deallocated by pcie_aspm_exit_link_state() after all
children of the bridge (but not the bridge itself) have been removed.
Previously pcie_aspm_enabled() acquired aspm_lock to ensure that
link_state was not deallocated while we're looking at it. But the fact
that the caller of pcie_aspm_enabled() holds a reference to @pdev means
there's always at least one child of the bridge, which means link_state
can't be deallocated.
Remove the unnecessary locking in pcie_aspm_enabled().
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- Consolidate _HPP & _HPX code in pci-acpi.h and remove unnecessary
struct hotplug_program_ops (Krzysztof Wilczynski)
- Fixup PCIe device types to remove the need for dev->has_secondary_link
(Mika Westerberg)
* pci/enumeration:
PCI: Get rid of dev->has_secondary_link flag
PCI: Make pcie_downstream_port() available outside of access.c
PCI/ACPI: Remove unnecessary struct hotplug_program_ops
PCI/ACPI: Move _HPP & _HPX functions to pci-acpi.c
PCI/ACPI: Rename _HPX structs from hpp_* to hpx_*
In some systems, the Device/Port Type in the PCI Express Capabilities
register incorrectly identifies upstream ports as downstream ports.
d0751b98df ("PCI: Add dev->has_secondary_link to track downstream PCIe
links") addressed this by adding pci_dev.has_secondary_link, which is set
for downstream ports. But this is confusing because pci_pcie_type()
sometimes gives the wrong answer, and it's not obvious that we should use
pci_dev.has_secondary_link instead.
Reduce the confusion by correcting the type of the port itself so that
pci_pcie_type() returns the actual type regardless of what the Device/Port
Type register claims it is. Update the users to call pci_pcie_type() and
pcie_downstream_port() accordingly, and remove pci_dev.has_secondary_link
completely.
Link: https://lore.kernel.org/linux-pci/20190703133953.GK128603@google.com/
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20190822085553.62697-2-mika.westerberg@linux.intel.com
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Move ASPM definitions and function prototypes from include/linux/pci-aspm.h
to include/linux/pci.h so users only need to include <linux/pci.h>:
PCIE_LINK_STATE_L0S
PCIE_LINK_STATE_L1
PCIE_LINK_STATE_CLKPM
pci_disable_link_state()
pci_disable_link_state_locked()
pcie_no_aspm()
No functional changes intended.
Link: https://lore.kernel.org/r/20190827095620.11213-1-kw@linux.com
Signed-off-by: Krzysztof Wilczynski <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Add a function checking whether or not PCIe ASPM has been enabled for
a given device.
It will be used by the NVMe driver to decide how to handle the
device during system suspend.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Drivers may rely on pci_disable_link_state() having disabled certain
ASPM link states. If OS can't control ASPM then pci_disable_link_state()
turns into a no-op w/o informing the caller. The driver therefore may
falsely assume the respective ASPM link states are disabled.
Let pci_disable_link_state() propagate errors to the caller, enabling
the caller to react accordingly.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Transform wait code to a "do {} while (time_before())" loop as recommended
by reviewer. No functional change intended.
Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Due to an erratum in some Pericom PCIe-to-PCI bridges in reverse mode
(conventional PCI on primary side, PCIe on downstream side), the Retrain
Link bit needs to be cleared manually to allow the link training to
complete successfully.
If it is not cleared manually, the link training is continuously restarted
and no devices below the PCI-to-PCIe bridge can be accessed. That means
drivers for devices below the bridge will be loaded but won't work and may
even crash because the driver is only reading 0xffff.
See the Pericom Errata Sheet PI7C9X111SLB_errata_rev1.2_102711.pdf for
details. Devices known as affected so far are: PI7C9X110, PI7C9X111SL,
PI7C9X130.
Add a new flag, clear_retrain_link, in struct pci_dev. Quirks for affected
devices set this bit.
Note that pcie_retrain_link() lives in aspm.c because that's currently the
only place we use it, but this erratum is not specific to ASPM, and we may
retrain links for other reasons in the future.
Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>
[bhelgaas: apply regardless of CONFIG_PCIEASPM]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
CC: stable@vger.kernel.org
Factor out pcie_retrain_link() to use for Pericom Retrain Link quirk. No
functional change intended.
Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
CC: stable@vger.kernel.org
ASPM does not make use of the children or link LIST_HEADs declared in
struct pcie_link_state and defined in alloc_pcie_link_state(). Therefore,
remove these lists.
No functional change intended.
Signed-off-by: Frederick Lawler <fred@fredlawl.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This reverts commit 17c9148736.
Rafael found that this commit broke the SD card reader in his
Acer Aspire S5. Details of the problem are in the bugzilla below.
Fixes: 17c9148736 ("PCI/ASPM: Do not initialize link state when aspm_disabled is set")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=201801
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Now that ASPM is configured for *all* PCIe devices at boot, a problem is
seen with systems that set the FADT NO_ASPM bit. This bit indicates that
the OS should not alter the ASPM state, but when
pcie_aspm_init_link_state() runs it only checks for !aspm_support_enabled.
This misses the ACPI_FADT_NO_ASPM case because that is setting
aspm_disabled.
The result is systems may hang at boot after 1302fcf; avoidable if they
boot with pcie_aspm=off (sets !aspm_support_enabled).
Fix this by having aspm_init_link_state() check for either
!aspm_support_enabled or acpm_disabled.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=201001
Fixes: 1302fcf0d0 ("PCI: Configure *all* devices, not just hot-added ones")
Signed-off-by: Patrick Talbert <ptalbert@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Upon removal of the last device on a bus, the link_state of the bridge
leading to that bus is sought to be torn down by having pci_stop_dev()
call pcie_aspm_exit_link_state().
When ASPM was originally introduced by commit 7d715a6c1a ("PCI: add
PCI Express ASPM support"), it determined whether the device being
removed is the last one by calling list_empty() on the bridge's
subordinate devices list. That didn't work because the device is only
removed from the list slightly later in pci_destroy_dev().
Commit 3419c75e15 ("PCI: properly clean up ASPM link state on device
remove") attempted to fix it by calling list_is_last(), but that's not
correct either because it checks whether the device is at the *end* of
the list, not whether it's the last one *left* in the list. If the user
removes the device which happens to be at the end of the list via sysfs
but other devices are preceding the device in the list, the link_state
is torn down prematurely.
The real fix is to move the invocation of pcie_aspm_exit_link_state() to
pci_destroy_dev() and reinstate the call to list_empty(). Remove a
duplicate check for dev->bus->self because pcie_aspm_exit_link_state()
already contains an identical check.
Fixes: 7d715a6c1a ("PCI: add PCI Express ASPM support")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: stable@vger.kernel.org # v2.6.26
The sysfs_match_string() helper returns index of the matching string in an
array. Use it in pcie_aspm_set_policy() to simplify the code.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[bhelgaas: squash sysfs_match_string() fix into original patch for issue
Reported-by: Heiner Kallweit <hkallweit1@gmail.com>]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
When in the ASPM L1.0 state (but not the PCI-PM L1.0 state), the most
recent LTR value and the LTR_L1.2_THRESHOLD determines whether the link
enters the L1.2 substate.
If we don't have LTR enabled, prevent the use of ASPM L1.2.
PCI-PM L1.2 may still be used because it doesn't depend on
LTR_L1.2_THRESHOLD (see PCIe r4.0, sec 5.5.1).
Tested-by: Srinath Mannam <srinath.mannam@broadcom.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- use PCI_EXP_DEVCTL2_COMP_TIMEOUT in rapidio/tsi721 (Bjorn Helgaas)
- remove possible NULL pointer dereference in of_pci_bus_find_domain_nr()
(Shawn Lin)
- report quirk timings with dev_info (Bjorn Helgaas)
- report quirks that take longer than 10ms (Bjorn Helgaas)
- add and use Altera Vendor ID (Johannes Thumshirn)
- tidy Makefiles and comments (Bjorn Helgaas)
* pci/misc:
PCI: Always define the of_node helpers
PCI: Tidy comments
PCI: Tidy Makefiles
mcb: Add Altera PCI ID to mcb-pci
PCI: Add Altera vendor ID
PCI: Report quirks that take more than 10ms
PCI: Report quirk timings with pci_info() instead of pr_debug()
PCI: Fix NULL pointer dereference in of_pci_bus_find_domain_nr()
rapidio/tsi721: use PCI_EXP_DEVCTL2_COMP_TIMEOUT macro
Remove pointless comments that tell us the file name, remove blank line
comments, follow multi-line comment conventions. No functional change
intended.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we emitted a warning if we tried to configure common clock mode
the link was already configured to common clock mode by the UEFI BIOS.
Bail out silently in that case instead of emitting the warning:
pci 0004:00:00.0: ASPM: Could not configure common clock
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>
aspm_calc_l1ss_info() computes l1_2_threshold in microseconds as:
l1_2_threshold = 2 + 4 + t_common_mode + t_power_on;
where t_common_mode is at most 255us:
PCI_L1SS_CAP_CM_RESTORE_TIME 0x0000ff00 <-- 8 bits; <256us
and t_power_on is at most 31 * 100us = 3100us:
PCI_L1SS_CAP_P_PWR_ON_VALUE 0x00f80000 <-- 5 bits; <32
PCI_L1SS_CAP_P_PWR_ON_SCALE 0x00030000 <-- *2us, *10us, or *100us
So l1_2_threshold is at most 2 + 4 + 255 + 3100 = 3361, which means
threshold_ns is at most 3361 * 1000 = 3361000, which easily fits in a
u32.
Declare threshold_ns as u32, not u64. This fixes a Coverity warning.
Addresses-Coverity-ID: 1462501
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
* pci/misc:
PCI: Add dummy pci_irqd_intx_xlate() for CONFIG_PCI=n build
PCI: Add wrappers for dev_printk()
PCI: Remove unnecessary messages for memory allocation failures
PCI: Add #defines for Completion Timeout Disable feature
hinic: Replace PCI pool old API
net: e100: Replace PCI pool old API
block: DAC960: Replace PCI pool old API
MAINTAINERS: Include more PCI files
PCI: Remove unneeded kallsyms include
powerpc/pci: Unroll two pass loop when scanning bridges
powerpc/pci: Use for_each_pci_bridge() helper
Add PCI-specific dev_printk() wrappers and use them to simplify the code
slightly. No functional change intended.
Signed-off-by: Frederick Lawler <fred@fredlawl.com>
[bhelgaas: squash into one patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Per PCIe r3.1, sec 5.5.1, LTR_L1.2_THRESHOLD determines whether we enter
the L1.2 Link state: if L1.2 is enabled and downstream devices have
reported that they can tolerate latency of at least LTR_L1.2_THRESHOLD, we
must enter L1.2 when CLKREQ# is de-asserted.
The implication is that LTR_L1.2_THRESHOLD is the time required to
transition the Link from L0 to L1.2 and back to L0, and per sec 5.5.3.3.1,
Figures 5-16 and 5-17, it appears that the absolute minimum time for those
transitions would be T(POWER_OFF) + T(L1.2) + T(POWER_ON) + T(COMMONMODE).
Therefore, compute LTR_L1.2_THRESHOLD as:
2us T(POWER_OFF)
+ 4us T(L1.2)
+ T(POWER_ON)
+ T(COMMONMODE)
= LTR_L1.2_THRESHOLD
Previously we set LTR_L1.2_THRESHOLD to a fixed value of 163840ns
(163.84us):
#define LTR_L1_2_THRESHOLD_BITS ((1 << 21) | (1 << 23) | (1 << 30))
((1 << 21) | (1 << 23) | (1 << 30)) = 0x40a00000
LTR_L1.2_THRESHOLD_Value = (0x40a00000 & 0x03ff0000) >> 16 = 0xa0 = 160
LTR_L1.2_THRESHOLD_Scale = (0x40a00000 & 0xe0000000) >> 29 = 0x2 (* 1024ns)
LTR_L1.2_THRESHOLD = 160 * 1024ns = 163840ns
Obviously this doesn't account for the circuit characteristics of different
implementations.
Note that while firmware may enable LTR, Linux itself currently does not
enable LTR. When L1.2 is enabled but LTR is not, LTR_L1.2_THRESHOLD is
ignored and we always enter L1.2 when it is enabled and CLKREQ# is
de-asserted. So this patch should not have any effect unless firmware
enables LTR.
Fixes: f1f0366dd6 ("PCI/ASPM: Calculate and save the L1.2 timing parameters")
Link: https://www.coreboot.org/pipermail/coreboot-gerrit/2015-March/021134.html
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Vidya Sagar <vidyas@nvidia.com>
Cc: Kenji Chen <kenji.chen@intel.com>
Cc: Patrick Georgi <pgeorgi@google.com>
Cc: Rajat Jain <rajatja@google.com>
Summary of modules changes for the 4.15 merge window:
- Treewide module_param_call() cleanup, fix up set/get function
prototype mismatches, from Kees Cook
- Minor code cleanups
Signed-off-by: Jessica Yu <jeyu@kernel.org>
-----BEGIN PGP SIGNATURE-----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=c8vb
-----END PGP SIGNATURE-----
Merge tag 'modules-for-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull module updates from Jessica Yu:
"Summary of modules changes for the 4.15 merge window:
- treewide module_param_call() cleanup, fix up set/get function
prototype mismatches, from Kees Cook
- minor code cleanups"
* tag 'modules-for-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module: Do not paper over type mismatches in module_param_call()
treewide: Fix function prototypes for module_param_call()
module: Prepare to convert all module_param_call() prototypes
kernel/module: Delete an error message for a failed memory allocation in add_module_usage()
Add and use #defines for L1 Substate register fields instead of hard-coding
the masks. Also update comments to use names from the spec. No functional
change intended.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Vidya Sagar <vidyas@nvidia.com>
Previously we programmed the LTR_L1.2_THRESHOLD in the parent (upstream)
device using the capability pointer of the *child* (downstream) device,
which corrupted some random word of the parent's config space.
Use the parent's L1 SS capability pointer to program its
LTR_L1.2_THRESHOLD.
Fixes: aeda9adeba ("PCI/ASPM: Configure L1 substate settings")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Vidya Sagar <vidyas@nvidia.com>
CC: stable@vger.kernel.org # v4.11+
CC: Rajat Jain <rajatja@google.com>
Every Port that supports the L1.2 substate advertises its Port
Common_Mode_Restore_Time, i.e., the time the Port requires to re-establish
common mode when exiting L1.2 (see PCIe r3.1, sec 7.33.2).
Per sec 5.5.3.3.1, when exiting L1.2, the Downstream Port (the device at
the upstream end of the link) must send TS1 training sequences for at least
T(COMMONMODE) after it detects electrical idle exit on the Link. We want
this to be long enough for both ends of the Link, so we should set it to
the maximum of the Port Common_Mode_Restore_Time for the upstream and
downstream components on the Link.
Previously we only looked at the Port Common_Mode_Restore_Time of the
upstream device, so if the downstream device required more time, we didn't
program the upstream device's T(COMMONMODE) correctly.
Fixes: f1f0366dd6 ("PCI/ASPM: Calculate and save the L1.2 timing parameters")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Vidya Sagar <vidyas@nvidia.com>
Acked-by: Rajat Jain <rajatja@google.com>
CC: stable@vger.kernel.org # v4.11+
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Several function prototypes for the set/get functions defined by
module_param_call() have a slightly wrong argument types. This fixes
those in an effort to clean up the calls when running under type-enforced
compiler instrumentation for CFI. This is the result of running the
following semantic patch:
@match_module_param_call_function@
declarer name module_param_call;
identifier _name, _set_func, _get_func;
expression _arg, _mode;
@@
module_param_call(_name, _set_func, _get_func, _arg, _mode);
@fix_set_prototype
depends on match_module_param_call_function@
identifier match_module_param_call_function._set_func;
identifier _val, _param;
type _val_type, _param_type;
@@
int _set_func(
-_val_type _val
+const char * _val
,
-_param_type _param
+const struct kernel_param * _param
) { ... }
@fix_get_prototype
depends on match_module_param_call_function@
identifier match_module_param_call_function._get_func;
identifier _val, _param;
type _val_type, _param_type;
@@
int _get_func(
-_val_type _val
+char * _val
,
-_param_type _param
+const struct kernel_param * _param
) { ... }
Two additional by-hand changes are included for places where the above
Coccinelle script didn't notice them:
drivers/platform/x86/thinkpad_acpi.c
fs/lockd/svc.c
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Even though it is unconventional, some PCIe host implementations omit the
root ports entirely, and simply consist of a host bridge (which is not
modeled as a device in the PCI hierarchy) and a link.
When the downstream device is an endpoint, our current code does not seem
to mind this unusual configuration. However, when PCIe switches are
involved, the ASPM code assumes that any downstream switch port has a
parent, and blindly dereferences the bus->parent->self field of the pci_dev
struct to chain the downstream link state to the link state of the root
port. Given that the root port is missing, the link is not modeled at all,
and nor is the link state, and attempting to access it results in a NULL
pointer dereference and a crash.
Avoid this by allowing the link state chain to terminate at the downstream
port if no root port exists.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
We call pcie_aspm_exit_link_state() when we remove a device. If the device
is the last PCIe function to be removed below a bridge and the bridge has
an ASPM link_state struct, we disable ASPM on the link. Disabling ASPM
requires link->downstream (used in pcie_config_aspm_link()).
We previously set link->downstream in pcie_aspm_cap_init(), but only if the
device was not blacklisted. Removing the blacklisted device caused a NULL
pointer dereference in the pcie_aspm_exit_link_state() ->
pcie_config_aspm_link() path:
# echo 1 > /sys/bus/pci/devices/0000\:0b\:00.0/remove
...
BUG: unable to handle kernel NULL pointer dereference at 0000000000000080
IP: pcie_config_aspm_link+0x5d/0x2b0
Call Trace:
pcie_aspm_exit_link_state+0x75/0x130
pci_stop_bus_device+0xa4/0xb0
pci_stop_and_remove_bus_device_locked+0x1a/0x30
remove_store+0x50/0x70
dev_attr_store+0x18/0x30
sysfs_kf_write+0x44/0x60
kernfs_fop_write+0x10e/0x190
__vfs_write+0x28/0x110
? rcu_read_lock_sched_held+0x5d/0x80
? rcu_sync_lockdep_assert+0x2c/0x60
? __sb_start_write+0x173/0x1a0
? vfs_write+0xb3/0x180
vfs_write+0xc4/0x180
SyS_write+0x49/0xa0
do_syscall_64+0xa6/0x1c0
entry_SYSCALL64_slow_path+0x25/0x25
---[ end trace bd187ee0267df5d9 ]---
To avoid this, set link->downstream in alloc_pcie_link_state(), so every
pcie_link_state structure has a valid link->downstream pointer.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rajat Jain <rajatja@google.com>
CC: stable@vger.kernel.org
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=4Owc
-----END PGP SIGNATURE-----
Merge tag 'pci-v4.11-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI updates from Bjorn Helgaas:
- add ASPM L1 substate support
- enable PCIe Extended Tags when supported
- configure PCIe MPS settings on iProc, Versatile, X-Gene, and Xilinx
- increase VPD access timeout
- add ACS quirks for Intel Union Point, Qualcomm QDF2400 and QDF2432
- use new pci_irq_alloc_vectors() in more drivers
- fix MSI affinity memory leak
- remove unused MSI interfaces and update documentation
- remove unused AER .link_reset() callback
- avoid pci_lock / p->pi_lock deadlock seen with perf
- serialize sysfs enable/disable num_vfs operations
- move DesignWare IP from drivers/pci/host/ to drivers/pci/dwc/ and
refactor so we can support both hosts and endpoints
- add DT ECAM-like support for HiSilicon Hip06/Hip07 controllers
- add Rockchip system power management support
- add Thunder-X cn81xx and cn83xx support
- add Exynos 5440 PCIe PHY support
* tag 'pci-v4.11-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (93 commits)
PCI: dwc: Remove dependency of designware on CONFIG_PCI
PCI: dwc: Add CONFIG_PCIE_DW_HOST to enable PCI dwc host
PCI: dwc: Split pcie-designware.c into host and core files
PCI: dwc: designware: Fix style errors in pcie-designware.c
PCI: dwc: designware: Parse "num-lanes" property in dw_pcie_setup_rc()
PCI: dwc: all: Split struct pcie_port into host-only and core structures
PCI: dwc: designware: Get device pointer at the start of dw_pcie_host_init()
PCI: dwc: all: Rename cfg_read/cfg_write to read/write
PCI: dwc: all: Use platform_set_drvdata() to save private data
PCI: dwc: designware: Move register defines to designware header file
PCI: dwc: Use PTR_ERR_OR_ZERO to simplify code
PCI: dra7xx: Group PHY API invocations
PCI: dra7xx: Enable MSI and legacy interrupts simultaneously
PCI: dra7xx: Add support to force RC to work in GEN1 mode
PCI: dra7xx: Simplify probe code with devm_gpiod_get_optional()
PCI: Move DesignWare IP support to new drivers/pci/dwc/ directory
PCI: exynos: Support the PHY generic framework
Documentation: binding: Modify the exynos5440 PCIe binding
phy: phy-exynos-pcie: Add support for Exynos PCIe PHY
Documentation: samsung-phy: Add exynos-pcie-phy binding
...
Since the exit latencies for L1 substates are not advertised by a device,
it is not clear in spec how to do a L1 substate exit latency check. We
assume that the L1 exit latencies advertised by a device include L1
substate latencies (and hence do not do any check). If that is not true,
we should do some sort of check here.
(I'm not clear about what that check should like currently. I'd be glad to
take up any suggestions).
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Configure the L1 substate settings on the upstream and downstream devices,
while taking care of the rules dictated by the PCIe spec.
[bhelgaas: drop "inline"]
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The PCIe spec (r3.1, sec 7.33) says the L1 PM Substates Capability may be
implemented only in function 0.
Read the L1 substate capability structures of upstream and downstream
components of the link and set it up in the device structure.
[bhelgaas: add specific spec reference]
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Add support for ASPM L1 substates. For details about L1 substates, see the
PCIe r3.1 spec, which includes the ECN below in secs 5.5 and 7.33.
Add macros for the 4 new L1 substates, and add a new ASPM "POWER_SUPERSAVE"
policy that can be used to enable L1 substates on a system if desired. The
new policy is in a sense, a superset of the existing POWERSAVE policy. The
4 policies are now:
DEFAULT: Reads and uses whatever ASPM states BIOS enabled
PERFORMANCE: Everything except L0 disabled.
POWERSAVE: L0s and L1 enabled (but not L1 substates)
POWER_SUPERSAVE: L0s + L1 + L1 substates also enabled
[bhelgaas: add PCIe r3.1 spec reference]
Link: https://pcisig.com/sites/default/files/specification_documents/ECN_L1_PM_Substates_with_CLKREQ_31_May_2013_Rev10a.pdf
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
In a struct pcie_link_state, link->root points to the pcie_link_state of
the root of the PCIe hierarchy. For the topmost link, this points to
itself (link->root = link). For others, we copy the pointer from the
parent (link->root = link->parent->root).
Previously we recognized that Root Ports originated PCIe hierarchies, but
we treated PCI/PCI-X to PCIe Bridges as being in the middle of the
hierarchy, and when we tried to copy the pointer from link->parent->root,
there was no parent, and we dereferenced a NULL pointer:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000090
IP: [<ffffffff9e424350>] pcie_aspm_init_link_state+0x170/0x820
Recognize that PCI/PCI-X to PCIe Bridges originate PCIe hierarchies just
like Root Ports do, so link->root for these devices should also point to
itself.
Fixes: 51ebfc92b7 ("PCI: Enumerate switches below PCI-to-PCIe bridges")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=193411
Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1022181
Tested-by: lists@ssl-mail.com
Tested-by: Jayachandran C. <jnair@caviumnetworks.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org # v4.2+
Some (defective) PCIe devices are not able to reliably do link retraining.
Check to see if ASPM is possible between link partners before configuring
common clocking, and doing the resulting link retraining. If ASPM is not
possible, there is no reason to risk losing access to a device due to an
unnecessary link retraining.
Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Use DEVICE_ATTR_RW for read-write attributes. This simplifies the source
code, improves readability, and reduces the chance of inconsistencies.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@rw@
declarer name DEVICE_ATTR;
identifier x,x_show,x_store;
@@
DEVICE_ATTR(x, \(0644\|S_IRUGO|S_IWUSR\), x_show, x_store);
@script:ocaml@
x << rw.x;
x_show << rw.x_show;
x_store << rw.x_store;
@@
if not (x^"_show" = x_show && x^"_store" = x_store)
then Coccilib.include_match false
@@
declarer name DEVICE_ATTR_RW;
identifier rw.x,rw.x_show,rw.x_store;
@@
- DEVICE_ATTR(x, \(0644\|S_IRUGO|S_IWUSR\), x_show, x_store);
+ DEVICE_ATTR_RW(x);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Without supporting clock PM capable, if we want to disable clkpm, we don't
need this extra check as it must already be zero for the enable argument.
And it's the same for enabling clkpm here. So let's remove this check.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
If CONFIG_PCIEASPM_DEBUG is set, then PCI devices have a link_state
attribute. Reading that attribute shows the state as a bit mask: 1
means L0S upstream, 2 means L0S downstream, and 4 means L1.
Oddly, writing to link_state is inconsistent and gets translated, leading
to mysterious results in which the value you store isn't comparable the
value you load back out.
Fix it by making link_state_store() match link_state_show().
[bhelgaas: Check "aspm_disabled" *before* validating input. When
"aspm_disabled" is set, this changes the error for invalid input from
-EINVAL to -EPERM.]
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Update the Link Control Enable Clock Power Management bit the same
way we update the ASPM Control bits, with a single call of
pcie_capability_clear_and_set_word().
No functional change; this just makes both paths use the same style.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
We allocate pcie_link_state for the component at the upstream end of a
Link. Previously we did this by allocating pcie_link_state for Root Ports
and Downstream Ports. This works fine for the typical topology:
00:1c.0 Root Port [bridge to bus 02]
02:00.0 Upstream Port [bridge to bus 03]
03:00.0 Downstream Port [bridge to bus 04]
04:00.0 Endpoint or Switch Port
However, it is possible to have a Root Port connected to a Downstream Port
instead of an Upstream Port, as in Robert White's ATCA system:
00:1c.0 Root Port [bridge to bus 02]
02:00.0 Downstream Port [bridge to bus 03]
03:01.0 Downstream Port [bridge to bus 04]
04:00.0 Endpoint or Switch Port
In this topology, we wrongly allocated pcie_link_state for the 02:00.0
Downstream Port, which is actually the *downstream* end of a link. This
led to the following NULL pointer dereference when we tried to connect this
link into the tree of links starting at the 00:1c.0 Root Port:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000088
IP: [<ffffffff81550324>] pcie_aspm_init_link_state+0x744/0x850
Hardware name: Kontron B3001/B3001, BIOS 4.6.3 08/07/2012
Call Trace:
[<ffffffff8153b865>] pci_scan_slot+0xd5/0x120
[<ffffffff8153ca1d>] pci_scan_child_bus+0x2d/0xd0
...
Instead of relying on the component type to identify the upstream end of a
link, use the "dev->has_secondary_link" field.
This means it's now possible for an Upstream Port to have a link on its
secondary side, so alloc_pcie_link_state() needs to connect links
originating from both Upstream and Downstream Ports into the tree.
[bhelgaas: changelog, add comment]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=94361
Link: http://lkml.kernel.org/r/54EB81B2.4050904@pobox.com
Reported-by: Robert White <rwhite@pobox.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
We decide in alloc_pcie_link_state() whether to allocate a pcie_link_state
for a device. After that, it's sufficient to check pdev->link_state. We
don't need to check the PCIe port type again.
Remove the redundant PCIe port type checking.
[bhelgaas: changelog]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
After 387d37577f ("PCI: Don't clear ASPM bits when the FADT declares it's
unsupported"), the "force" parameter to __pci_disable_link_state() is
always "false".
Remove the "force" parameter and assume it's always false.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Communications with a hardware vendor confirm that the expected behaviour
on systems that set the FADT ASPM disable bit but which still grant full
PCIe control is for the OS to leave any BIOS configuration intact and
refuse to touch the ASPM bits. This mimics the behaviour of Windows.
Signed-off-by: Matthew Garrett <mjg59@coreos.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The functions link_state_store() and clk_ctl_store() had just subtracted
ASCII '0' from input which could lead to undesired results. Instead, use
Linux string functions to safely parse input.
[bhelgaas: check kstrtouint() return value]
Signed-off-by: Chris J Arges <chris.j.arges@canonical.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
My philosophy is unused code is dead code. And dead code is subject to bit
rot and is a likely source of bugs. Use it or lose it.
This reverts part of 3e1b16002a ("ACPI/PCI: PCIe ASPM _OSC support
capabilities called when root bridge added"), removing this interface:
pcie_aspm_enabled()
[bhelgaas: split to separate patch]
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Andrew Patterson <andrew.patterson@hp.com>
Fix whitespace, capitalization, and spelling errors. No functional change.
I know "busses" is not an error, but "buses" was more common, so I used it
consistently.
Signed-off-by: Marta Rybczynska <rybczynska@gmail.com> (pci_reset_bridge_secondary_bus())
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Some devices have hardware problems related to using ASPM. Drivers for
these devices use pci_disable_link_state() to prevent their device from
entering L0s or L1. But on platforms where the OS doesn't have permission
to manage ASPM, pci_disable_link_state() doesn't actually disable ASPM.
Windows has a similar mechanism ("PciASPMOptOut"), and when the OS doesn't
have control of ASPM, it doesn't actually disable ASPM either.
This patch just adds a warning in dmesg about the fact that
pci_disable_link_state() is doing nothing.
Reported-by: Emmanuel Grumbach <egrumbach@gmail.com>
Reference: https://lkml.kernel.org/r/CANUX_P3F5YhbZX3WGU-j1AGpbXb_T9Bis2ErhvKkFMtDvzatVQ@mail.gmail.com
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=57331
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
