From: Bartosz Golaszewski <[email protected]>
Note: I dropped most of the the review and test tags on purpose, the code
changed significantly and warrants a new round of reviews and tests.
===
Problem statement #1: Dynamic bus chicken-and-egg problem.
Certain on-board PCI devices need to be powered up before they are can be
detected but their PCI drivers won't get bound until the device is
powered-up so enabling the relevant resources in the PCI device driver
itself is impossible.
Problem statement #2: Sharing inter-dependent resources between devices.
Certain devices that use separate drivers (often on different busses)
share resources (regulators, clocks, etc.). Typically these resources
are reference-counted but in some cases there are additional interactions
between them to consider, for example specific power-up sequence timings.
===
The reason for tackling both of these problems in a single series is the
fact the the platform I'm working on - Qualcomm RB5 - deals with both and
both need to be addressed in order to enable WLAN and Bluetooth support
upstream.
The on-board WLAN/BT package - QCA6391 - has a Power Management Unit that
takes inputs from the host and exposes LDO outputs consumed by the BT and
WLAN modules which can be powered-up and down independently. However
a delay of 100ms must be respected between enabling the BT- and
WLAN-enable GPIOs.
A similar design with a discreet PMU is also employed in other models of
the WCN family of chips although we can often do without the delays. With
this series we add support for the WCN7850 as well.
===
We introduce a new subsystem here - the power sequencing framework. The
qcom-wcn driver that we add is its first user. It implements the power-up
sequences for QCA6390 and WCN7850 chips. However - we only use it to
power-up the bluetooth module in the former. We use it to driver the WLAN
modules in both. The reason for this is that for WCN7850 we have
comprehensive bindings already upstream together with existing DT users.
Porting them to using the pwrseq subsystem can be done separately and in
an incremental manner once the subsystem itself is upstream. We will also
have to ensure backward DT compatibility. To avoid overcomplicating this
series, let's leave it out for now.
===
This series is logically split into several sections. I'll go
patch-by-patch and explain each step.
Patches 1/16-5/16:
These contain all relevant DT bindings changes. We add new documents for
the QCA6390 & WCN7850 PMUs and ATH12K devices as well as extend the bindings
for the Qualcomm Bluetooth and ATH11K modules with regulators used by them
in QCA6390.
Patches 6/16-8/16:
These contain changes to device-tree sources for the three platforms we
work with in this series. We model the PMUs of the WLAN/BT chips as
top-level platform devices on the device tree. In order to limit the scope
of this series and not introduce an excessive amount of confusion with
deprecating DT bindings, we leave the Bluetooth nodes on sm8650 and sm8550
as is (meaning: they continue to consumer the GPIOs and power inputs from
the host). As the WCN7850 module doesn't require any specific timings, we can
incrementally change that later.
In both cases we add WLAN nodes that consume the power outputs of the PMU.
For QCA6390 we also make the Bluetooth node of the RB5 consume the outputs
of the PMU - we can do it as the bindings for this chip did not define any
supply handles prior to this series meaning we are able to get this correct
right away.
Patches 9/16-12/16:
These contain the bulk of the PCI changes for this series. We introduce
a simple framework for powering up PCI devices before detecting them on
the bus.
The general approach is as follows: PCI devices that need special
treatment before they can be powered up, scanned and bound to their PCI
drivers must be described on the device-tree as child nodes of the PCI
port node. These devices will be instantiated on the platform bus. They
will in fact be generic platform devices with the compatible of the form
used for PCI devices already upstream ("pci<vendor ID>,<device ID">). We
add a new directory under drivers/pci/pwrctl/ that contains PCI pwrctl
drivers. These drivers are platform drivers that will now be matched
against the devices instantiated from port children just like any other
platform pairs.
Both the power control platform device *AND* the associated PCI device
reuse the same OF node and have access to the same properties. The goal
of the platform driver is to request and bring up any required resources
and let the pwrctl framework know that it's now OK to rescan the bus and
detect the devices. When the device is bound, we are notified about it
by the PCI bus notifier event and can establish a device link between the
power control device and the PCI device so that any future extension for
power-management will already be able to work with the correct hierachy.
The reusing of the OF node is the reason for the small changes to the PCI
OF core: as the bootloader can possibly leave the relevant regulators on
before booting linux, the PCI device can be detected before its platform
abstraction is probed. In this case, we find that device first and mark
its OF node as reused. The pwrctl framework handles the opposite case
(when the PCI device is detected only after the platform driver
successfully enabled it).
Patch 13/16 - 14/16:
These add a relatively simple power sequencing subsystem and the first
driver using it: the pwrseq module for the PMUs on the WCN family of chips.
I'm proposing to add a subsystem that allows different devices to use a shared
power sequence split into consumer-specific as well as common "units".
A power sequence provider driver registers a set of units with pwrseq
core. Each unit can be enabled and disabled and contains an optional list
of other units which must be enabled before it itself can be. A unit
represents a discreet chunk of the power sequence.
It also registers a list of targets: a target is an abstraction wrapping
a unit which allows consumers to tell pwrseq which unit they want to
reach. Real-life example is the driver we're adding here: there's a set
of common regulators, two PCIe-specific ones and two enable GPIOs: one
for Bluetooth and one for WLAN.
The Bluetooth driver requests a descriptor to the power sequencer and
names the target it wants to reach:
pwrseq = devm_pwrseq_get(dev, "bluetooth");
The pwrseq core then knows that when the driver calls:
pwrseq_power_on(pwrseq);
It must enable the "bluetooth-enable" unit but it depends on the
"regulators-common" unit so this one is enabled first. The provider
driver is also in charge of assuring an appropriate delay between
enabling the BT and WLAN enable GPIOs. The WLAN-specific resources are
handled by the "wlan-enable" unit and so are not enabled until the WLAN
driver requests the "wlan" target to be powered on.
Another thing worth discussing is the way we associate the consumer with
the relevant power sequencer. DT maintainers have expressed a discontent
with the existing mmc pwrseq bindings and have NAKed an earlier
initiative to introduce global pwrseq bindings to the kernel[1].
In this approach, we model the existing regulators and GPIOs in DT but
the pwrseq subsystem requires each provider to provide a .match()
callback. Whenever a consumer requests a power sequencer handle, we
iterate over the list of pwrseq drivers and call .match() for each. It's
up to the driver to verify in a platform-specific way whether it deals
with its consumer and let the core pwrseq code know.
The advantage of this over reusing the regulator or reset subsystem is
that it's more generalized and can handle resources of all kinds as well
as deal with any kind of power-on sequences: for instance, Qualcomm has
a PCI switch they want a driver for but this switch requires enabling
some resources first (PCI pwrctl) and then configuring the device over
I2C (which can be handled by the pwrseq provider).
Patch 15:
This patch makes the Qualcomm Bluetooth driver get and use the power
sequencer for QCA6390.
Patch 16:
While tiny, this patch is possibly the highlight of the entire series.
It uses the two abstraction layers we introduced before to create an
elegant power sequencing PCI power control driver and supports the ath11k
module on QCA6390 and ath12k on WCN7850.
With this series we can now enable BT and WLAN on several new Qualcomm
boards upstream.
Tested on RB5, sm8650-qrd and sm8550-qrd.
Changelog:
Since v5:
- unify the approach to modelling the WCN WLAN/BT chips by always exposing
the PMU node on the device tree and making the WLAN and BT nodes become
consumers of its power outputs; this includes a major rework of the DT
sources, bindings and driver code; there's no more a separate PCI
pwrctl driver for WCN7850, instead its power-up sequence was moved
into the pwrseq driver common for all WCN chips
- don't set load_uA from new regulator consumers
- fix reported kerneldoc issues
- drop voltage ranges for PMU outputs from DT
- many minor tweaks and reworks
v1: Original RFC:
https://lore.kernel.org/lkml/[email protected]/T/
v2: First real patch series (should have been PATCH v2) adding what I
referred to back then as PCI power sequencing:
https://lore.kernel.org/linux-arm-kernel/2024021413-grumbling-unlivable-c145@gregkh/T/
v3: RFC for the DT representation of the PMU supplying the WLAN and BT
modules inside the QCA6391 package (was largely separate from the
series but probably should have been called PATCH or RFC v3):
https://lore.kernel.org/all/CAMRc=Mc+GNoi57eTQg71DXkQKjdaoAmCpB=h2ndEpGnmdhVV-Q@mail.gmail.com/T/
v4: Second attempt at the full series with changed scope (introduction of
the pwrseq subsystem, should have been RFC v4)
https://lore.kernel.org/lkml/[email protected]/T/
v5: Two different ways of handling QCA6390 and WCN7850:
https://lore.kernel.org/lkml/[email protected]/
Bartosz Golaszewski (16):
regulator: dt-bindings: describe the PMU module of the QCA6390 package
regulator: dt-bindings: describe the PMU module of the WCN7850 package
dt-bindings: net: bluetooth: qualcomm: describe regulators for QCA6390
dt-bindings: net: wireless: qcom,ath11k: describe the ath11k on
QCA6390
dt-bindings: net: wireless: describe the ath12k PCI module
arm64: dts: qcom: sm8550-qrd: add the Wifi node
arm64: dts: qcom: sm8650-qrd: add the Wifi node
arm64: dts: qcom: qrb5165-rb5: add the Wifi node
PCI: hold the rescan mutex when scanning for the first time
PCI/pwrctl: reuse the OF node for power controlled devices
PCI/pwrctl: create platform devices for child OF nodes of the port
node
PCI/pwrctl: add PCI power control core code
power: sequencing: implement the pwrseq core
power: pwrseq: add a driver for the PMU module on the QCom WCN
chipsets
Bluetooth: qca: use the power sequencer for QCA6390
PCI/pwrctl: add a PCI power control driver for power sequenced devices
.../net/bluetooth/qualcomm-bluetooth.yaml | 17 +
.../net/wireless/qcom,ath11k-pci.yaml | 46 +
.../bindings/net/wireless/qcom,ath12k.yaml | 100 ++
.../bindings/regulator/qcom,qca6390-pmu.yaml | 185 +++
MAINTAINERS | 8 +
arch/arm64/boot/dts/qcom/qrb5165-rb5.dts | 103 +-
arch/arm64/boot/dts/qcom/sm8250.dtsi | 10 +
arch/arm64/boot/dts/qcom/sm8550-qrd.dts | 97 ++
arch/arm64/boot/dts/qcom/sm8550.dtsi | 10 +
arch/arm64/boot/dts/qcom/sm8650-qrd.dts | 89 ++
arch/arm64/boot/dts/qcom/sm8650.dtsi | 10 +
drivers/bluetooth/hci_qca.c | 74 +-
drivers/pci/Kconfig | 1 +
drivers/pci/Makefile | 1 +
drivers/pci/bus.c | 9 +-
drivers/pci/of.c | 14 +-
drivers/pci/probe.c | 2 +
drivers/pci/pwrctl/Kconfig | 17 +
drivers/pci/pwrctl/Makefile | 6 +
drivers/pci/pwrctl/core.c | 136 +++
drivers/pci/pwrctl/pci-pwrctl-pwrseq.c | 89 ++
drivers/pci/remove.c | 2 +
drivers/power/Kconfig | 1 +
drivers/power/Makefile | 1 +
drivers/power/sequencing/Kconfig | 28 +
drivers/power/sequencing/Makefile | 6 +
drivers/power/sequencing/core.c | 1065 +++++++++++++++++
drivers/power/sequencing/pwrseq-qcom-wcn.c | 336 ++++++
include/linux/pci-pwrctl.h | 51 +
include/linux/pwrseq/consumer.h | 56 +
include/linux/pwrseq/provider.h | 75 ++
31 files changed, 2614 insertions(+), 31 deletions(-)
create mode 100644 Documentation/devicetree/bindings/net/wireless/qcom,ath12k.yaml
create mode 100644 Documentation/devicetree/bindings/regulator/qcom,qca6390-pmu.yaml
create mode 100644 drivers/pci/pwrctl/Kconfig
create mode 100644 drivers/pci/pwrctl/Makefile
create mode 100644 drivers/pci/pwrctl/core.c
create mode 100644 drivers/pci/pwrctl/pci-pwrctl-pwrseq.c
create mode 100644 drivers/power/sequencing/Kconfig
create mode 100644 drivers/power/sequencing/Makefile
create mode 100644 drivers/power/sequencing/core.c
create mode 100644 drivers/power/sequencing/pwrseq-qcom-wcn.c
create mode 100644 include/linux/pci-pwrctl.h
create mode 100644 include/linux/pwrseq/consumer.h
create mode 100644 include/linux/pwrseq/provider.h
--
2.40.1
From: Bartosz Golaszewski <[email protected]>
QCA6390 has a compatible listed in the bindings but is missing the
regulators description. Add the missing supply property and list the
required ones in the allOf section.
Signed-off-by: Bartosz Golaszewski <[email protected]>
Reviewed-by: Krzysztof Kozlowski <[email protected]>
---
.../net/bluetooth/qualcomm-bluetooth.yaml | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/Documentation/devicetree/bindings/net/bluetooth/qualcomm-bluetooth.yaml b/Documentation/devicetree/bindings/net/bluetooth/qualcomm-bluetooth.yaml
index 528ef3572b62..d844acaec1d3 100644
--- a/Documentation/devicetree/bindings/net/bluetooth/qualcomm-bluetooth.yaml
+++ b/Documentation/devicetree/bindings/net/bluetooth/qualcomm-bluetooth.yaml
@@ -62,6 +62,9 @@ properties:
vdddig-supply:
description: VDD_DIG supply regulator handle
+ vddbtcmx-supply:
+ description: VDD_BT_CMX supply regulator handle
+
vddbtcxmx-supply:
description: VDD_BT_CXMX supply regulator handle
@@ -180,6 +183,20 @@ allOf:
- vddrfa0p8-supply
- vddrfa1p2-supply
- vddrfa1p9-supply
+ - if:
+ properties:
+ compatible:
+ contains:
+ enum:
+ - qcom,qca6390-bt
+ then:
+ required:
+ - vddrfacmn-supply
+ - vddaon-supply
+ - vddbtcmx-supply
+ - vddrfa0p8-supply
+ - vddrfa1p2-supply
+ - vddrfa1p7-supply
examples:
- |
--
2.40.1
From: Bartosz Golaszewski <[email protected]>
Add device-tree bindings for the ATH12K module found in the WCN7850
package.
Signed-off-by: Bartosz Golaszewski <[email protected]>
---
.../bindings/net/wireless/qcom,ath12k.yaml | 100 ++++++++++++++++++
1 file changed, 100 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/wireless/qcom,ath12k.yaml
diff --git a/Documentation/devicetree/bindings/net/wireless/qcom,ath12k.yaml b/Documentation/devicetree/bindings/net/wireless/qcom,ath12k.yaml
new file mode 100644
index 000000000000..c0aad4815953
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/wireless/qcom,ath12k.yaml
@@ -0,0 +1,100 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# Copyright (c) 2024 Linaro Limited
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/wireless/qcom,ath12k.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm Technologies ath12k wireless devices (PCIe)
+
+maintainers:
+ - Bartosz Golaszewski <[email protected]>
+ - Jeff Johnson <[email protected]>
+ - Kalle Valo <[email protected]>
+
+description:
+ Qualcomm Technologies IEEE 802.11ax PCIe devices.
+
+properties:
+ compatible:
+ enum:
+ - pci17cb,1107 # WCN7850
+
+ reg:
+ maxItems: 1
+
+ vddaon-supply:
+ description: VDD_AON supply regulator handle
+
+ vddwlcx-supply:
+ description: VDD_WLCX supply regulator handle
+
+ vddwlmx-supply:
+ description: VDD_WLMX supply regulator handle
+
+ vddrfacmn-supply:
+ description: VDD_RFA_CMN supply regulator handle
+
+ vddrfa0p8-supply:
+ description: VDD_RFA_0P8 supply regulator handle
+
+ vddrfa1p2-supply:
+ description: VDD_RFA_1P2 supply regulator handle
+
+ vddrfa1p8-supply:
+ description: VDD_RFA_1P8 supply regulator handle
+
+ vddpcie0p9-supply:
+ description: VDD_PCIE_0P9 supply regulator handle
+
+ vddpcie1p8-supply:
+ description: VDD_PCIE_1P8 supply regulator handle
+
+required:
+ - compatible
+ - reg
+ - vddaon-supply
+ - vddwlcx-supply
+ - vddwlmx-supply
+ - vddrfacmn-supply
+ - vddrfa0p8-supply
+ - vddrfa1p2-supply
+ - vddrfa1p8-supply
+ - vddpcie0p9-supply
+ - vddpcie1p8-supply
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/clock/qcom,rpmh.h>
+ #include <dt-bindings/gpio/gpio.h>
+ pcie {
+ #address-cells = <3>;
+ #size-cells = <2>;
+
+ pcie@0 {
+ device_type = "pci";
+ reg = <0x0 0x0 0x0 0x0 0x0>;
+ #address-cells = <3>;
+ #size-cells = <2>;
+ ranges;
+
+ bus-range = <0x01 0xff>;
+
+ wifi@0 {
+ compatible = "pci17cb,1107";
+ reg = <0x10000 0x0 0x0 0x0 0x0>;
+
+ vddaon-supply = <&vreg_pmu_aon_0p59>;
+ vddwlcx-supply = <&vreg_pmu_wlcx_0p8>;
+ vddwlmx-supply = <&vreg_pmu_wlmx_0p85>;
+ vddrfacmn-supply = <&vreg_pmu_rfa_cmn>;
+ vddrfa0p8-supply = <&vreg_pmu_rfa_0p8>;
+ vddrfa1p2-supply = <&vreg_pmu_rfa_1p2>;
+ vddrfa1p8-supply = <&vreg_pmu_rfa_1p8>;
+ vddpcie0p9-supply = <&vreg_pmu_pcie_0p9>;
+ vddpcie1p8-supply = <&vreg_pmu_pcie_1p8>;
+ };
+ };
+ };
--
2.40.1
From: Bartosz Golaszewski <[email protected]>
Describe the ath12k WLAN on-board the WCN7850 module present on the
board.
[Neil: authored the initial version of the change]
Co-developed-by: Neil Armstrong <[email protected]>
Signed-off-by: Neil Armstrong <[email protected]>
Signed-off-by: Bartosz Golaszewski <[email protected]>
---
arch/arm64/boot/dts/qcom/sm8650-qrd.dts | 89 +++++++++++++++++++++++++
arch/arm64/boot/dts/qcom/sm8650.dtsi | 10 +++
2 files changed, 99 insertions(+)
diff --git a/arch/arm64/boot/dts/qcom/sm8650-qrd.dts b/arch/arm64/boot/dts/qcom/sm8650-qrd.dts
index b07cac2e5bc8..c87d21115716 100644
--- a/arch/arm64/boot/dts/qcom/sm8650-qrd.dts
+++ b/arch/arm64/boot/dts/qcom/sm8650-qrd.dts
@@ -203,6 +203,71 @@ wcd_codec_headset_in: endpoint {
};
};
};
+
+ wcn7850-pmu {
+ compatible = "qcom,wcn7850-pmu";
+
+ pinctrl-names = "default";
+ pinctrl-0 = <&wlan_en>;
+
+ wlan-enable-gpios = <&tlmm 16 GPIO_ACTIVE_HIGH>;
+ /*
+ * TODO Add bt-enable-gpios once the Bluetooth driver is
+ * converted to using the power sequencer.
+ */
+
+ vdd-supply = <&vreg_s4i_0p85>;
+ vddio-supply = <&vreg_l15b_1p8>;
+ vddio1p2-supply = <&vreg_l3c_1p2>;
+ vddaon-supply = <&vreg_s2c_0p8>;
+ vdddig-supply = <&vreg_s3c_0p9>;
+ vddrfa1p2-supply = <&vreg_s1c_1p2>;
+ vddrfa1p8-supply = <&vreg_s6c_1p8>;
+
+ clocks = <&rpmhcc RPMH_RF_CLK1>;
+
+ regulators {
+ vreg_pmu_rfa_cmn: ldo0 {
+ regulator-name = "vreg_pmu_rfa_cmn";
+ };
+
+ vreg_pmu_aon_0p59: ldo1 {
+ regulator-name = "vreg_pmu_aon_0p59";
+ };
+
+ vreg_pmu_wlcx_0p8: ldo2 {
+ regulator-name = "vreg_pmu_wlcx_0p8";
+ };
+
+ vreg_pmu_wlmx_0p85: ldo3 {
+ regulator-name = "vreg_pmu_wlmx_0p85";
+ };
+
+ vreg_pmu_btcmx_0p85: ldo4 {
+ regulator-name = "vreg_pmu_btcmx_0p85";
+ };
+
+ vreg_pmu_rfa_0p8: ldo5 {
+ regulator-name = "vreg_pmu_rfa_0p8";
+ };
+
+ vreg_pmu_rfa_1p2: ldo6 {
+ regulator-name = "vreg_pmu_rfa_1p2";
+ };
+
+ vreg_pmu_rfa_1p8: ldo7 {
+ regulator-name = "vreg_pmu_rfa_1p8";
+ };
+
+ vreg_pmu_pcie_0p9: ldo8 {
+ regulator-name = "vreg_pmu_pcie_0p9";
+ };
+
+ vreg_pmu_pcie_1p8: ldo9 {
+ regulator-name = "vreg_pmu_pcie_1p8";
+ };
+ };
+ };
};
&apps_rsc {
@@ -845,6 +910,23 @@ &pcie0 {
status = "okay";
};
+&pcieport0 {
+ wifi@0 {
+ compatible = "pci17cb,1107";
+ reg = <0x10000 0x0 0x0 0x0 0x0>;
+
+ vddrfacmn-supply = <&vreg_pmu_rfa_cmn>;
+ vddaon-supply = <&vreg_pmu_aon_0p59>;
+ vddwlcx-supply = <&vreg_pmu_wlcx_0p8>;
+ vddwlmx-supply = <&vreg_pmu_wlmx_0p85>;
+ vddrfa0p8-supply = <&vreg_pmu_rfa_0p8>;
+ vddrfa1p2-supply = <&vreg_pmu_rfa_1p2>;
+ vddrfa1p8-supply = <&vreg_pmu_rfa_1p8>;
+ vddpcie0p9-supply = <&vreg_pmu_pcie_0p9>;
+ vddpcie1p8-supply = <&vreg_pmu_pcie_1p8>;
+ };
+};
+
&pcie0_phy {
vdda-phy-supply = <&vreg_l1i_0p88>;
vdda-pll-supply = <&vreg_l3i_1p2>;
@@ -1139,6 +1221,13 @@ wcd_default: wcd-reset-n-active-state {
bias-disable;
output-low;
};
+
+ wlan_en: wlan-en-state {
+ pins = "gpio16";
+ function = "gpio";
+ drive-strength = <8>;
+ bias-pull-down;
+ };
};
&uart14 {
diff --git a/arch/arm64/boot/dts/qcom/sm8650.dtsi b/arch/arm64/boot/dts/qcom/sm8650.dtsi
index 78757f01a7d8..693857905fe9 100644
--- a/arch/arm64/boot/dts/qcom/sm8650.dtsi
+++ b/arch/arm64/boot/dts/qcom/sm8650.dtsi
@@ -2293,6 +2293,16 @@ &mc_virt SLAVE_EBI1 QCOM_ICC_TAG_ALWAYS>,
dma-coherent;
status = "disabled";
+
+ pcieport0: pcie@0 {
+ device_type = "pci";
+ reg = <0x0 0x0 0x0 0x0 0x0>;
+ #address-cells = <3>;
+ #size-cells = <2>;
+ ranges;
+
+ bus-range = <0x01 0xff>;
+ };
};
pcie0_phy: phy@1c06000 {
--
2.40.1
From: Bartosz Golaszewski <[email protected]>
With the introduction of PCI device power control drivers that will be
able to trigger the port rescan when probing, we need to hold the rescan
mutex during the initial pci_host_probe() too or the two could get in
each other's way.
Signed-off-by: Bartosz Golaszewski <[email protected]>
---
drivers/pci/probe.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 1325fbae2f28..1802900328a0 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -3066,7 +3066,9 @@ int pci_host_probe(struct pci_host_bridge *bridge)
struct pci_bus *bus, *child;
int ret;
+ pci_lock_rescan_remove();
ret = pci_scan_root_bus_bridge(bridge);
+ pci_unlock_rescan_remove();
if (ret < 0) {
dev_err(bridge->dev.parent, "Scanning root bridge failed");
return ret;
--
2.40.1
From: Bartosz Golaszewski <[email protected]>
With PCI power control we deal with two struct device objects bound to
two different drivers but consuming the same OF node. We must not bind
the pinctrl twice. To that end: before setting the OF node of the newly
instantiated PCI device, check if a platform device consuming the same
OF node doesn't already exist on the platform bus and - if so - mark the
PCI device as reusing the OF node.
Signed-off-by: Bartosz Golaszewski <[email protected]>
---
drivers/pci/of.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index 51e3dd0ea5ab..b908fe1ae951 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -6,6 +6,7 @@
*/
#define pr_fmt(fmt) "PCI: OF: " fmt
+#include <linux/cleanup.h>
#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/pci.h>
@@ -13,6 +14,7 @@
#include <linux/of_irq.h>
#include <linux/of_address.h>
#include <linux/of_pci.h>
+#include <linux/platform_device.h>
#include "pci.h"
#ifdef CONFIG_PCI
@@ -25,16 +27,20 @@
*/
int pci_set_of_node(struct pci_dev *dev)
{
- struct device_node *node;
-
if (!dev->bus->dev.of_node)
return 0;
- node = of_pci_find_child_device(dev->bus->dev.of_node, dev->devfn);
+ struct device_node *node __free(device_node) =
+ of_pci_find_child_device(dev->bus->dev.of_node, dev->devfn);
if (!node)
return 0;
- device_set_node(&dev->dev, of_fwnode_handle(node));
+ struct device *pdev __free(put_device) =
+ bus_find_device_by_of_node(&platform_bus_type, node);
+ if (pdev)
+ dev->bus->dev.of_node_reused = true;
+
+ device_set_node(&dev->dev, of_fwnode_handle(no_free_ptr(node)));
return 0;
}
--
2.40.1
From: Bartosz Golaszewski <[email protected]>
Implement the power sequencing subsystem allowing devices to share
complex powering-up and down procedures. It's split into the consumer
and provider parts but does not implement any new DT bindings so that
the actual power sequencing is never revealed in the DT representation.
Signed-off-by: Bartosz Golaszewski <[email protected]>
---
MAINTAINERS | 8 +
drivers/power/Kconfig | 1 +
drivers/power/Makefile | 1 +
drivers/power/sequencing/Kconfig | 12 +
drivers/power/sequencing/Makefile | 4 +
drivers/power/sequencing/core.c | 1065 +++++++++++++++++++++++++++++
include/linux/pwrseq/consumer.h | 56 ++
include/linux/pwrseq/provider.h | 75 ++
8 files changed, 1222 insertions(+)
create mode 100644 drivers/power/sequencing/Kconfig
create mode 100644 drivers/power/sequencing/Makefile
create mode 100644 drivers/power/sequencing/core.c
create mode 100644 include/linux/pwrseq/consumer.h
create mode 100644 include/linux/pwrseq/provider.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 51d5a64a5a36..37039fa1b721 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17631,6 +17631,14 @@ F: include/linux/pm_*
F: include/linux/powercap.h
F: kernel/configs/nopm.config
+POWER SEQUENCING
+M: Bartosz Golaszewski <[email protected]>
+L: [email protected]
+S: Maintained
+T: git git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git
+F: drivers/power/sequencing/
+F: include/linux/pwrseq/
+
POWER STATE COORDINATION INTERFACE (PSCI)
M: Mark Rutland <[email protected]>
M: Lorenzo Pieralisi <[email protected]>
diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index 696bf77a7042..9a8e44ca9ae4 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only
source "drivers/power/reset/Kconfig"
+source "drivers/power/sequencing/Kconfig"
source "drivers/power/supply/Kconfig"
diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index effbf0377f32..962a2cd30a51 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only
obj-$(CONFIG_POWER_RESET) += reset/
+obj-$(CONFIG_POWER_SEQUENCING) += sequencing/
obj-$(CONFIG_POWER_SUPPLY) += supply/
diff --git a/drivers/power/sequencing/Kconfig b/drivers/power/sequencing/Kconfig
new file mode 100644
index 000000000000..ba5732b1dbf8
--- /dev/null
+++ b/drivers/power/sequencing/Kconfig
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+menuconfig POWER_SEQUENCING
+ tristate "Power Sequencing support"
+ help
+ Say Y here to enable the Power Sequencing subsystem.
+
+ This subsystem is designed to control power to devices that share
+ complex resources and/or require specific power sequences to be run
+ during power-up.
+
+ If unsure, say no.
diff --git a/drivers/power/sequencing/Makefile b/drivers/power/sequencing/Makefile
new file mode 100644
index 000000000000..dcdf8c0c159e
--- /dev/null
+++ b/drivers/power/sequencing/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_POWER_SEQUENCING) += pwrseq-core.o
+pwrseq-core-y := core.o
diff --git a/drivers/power/sequencing/core.c b/drivers/power/sequencing/core.c
new file mode 100644
index 000000000000..f5f3dc9d2407
--- /dev/null
+++ b/drivers/power/sequencing/core.c
@@ -0,0 +1,1065 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2024 Linaro Ltd.
+ */
+
+#include <linux/bug.h>
+#include <linux/cleanup.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/idr.h>
+#include <linux/kernel.h>
+#include <linux/kref.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/property.h>
+#include <linux/pwrseq/consumer.h>
+#include <linux/pwrseq/provider.h>
+#include <linux/radix-tree.h>
+#include <linux/rwsem.h>
+#include <linux/slab.h>
+
+/*
+ * Power-sequencing framework for linux.
+ *
+ * This subsystem allows power sequence providers to register a set of targets
+ * that consumers may request and power-up/down.
+ *
+ * Glossary:
+ *
+ * Unit - a unit is a discreet chunk of a power sequence. For instance one unit
+ * may enable a set of regulators, another may enable a specific GPIO. Units
+ * can define dependencies in the form of other units that must be enabled
+ * before it itself can be.
+ *
+ * Target - a target is a set of units (composed of the "final" unit and its
+ * dependencies) that a consumer selects by its name when requesting a handle
+ * to the power sequencer. Via the dependency system, multiple targets may
+ * share the same parts of a power sequence but ignore parts that are
+ * irrelevant.
+ *
+ * Descriptor - a handle passed by the pwrseq core to every consumer that
+ * serves as the entry point to the provider layer. It ensures coherence
+ * between different users and keeps reference counting consistent.
+ *
+ * Each provider must define a .match() callback whose role is to determine
+ * whether a potential consumer is in fact associated with this sequencer.
+ * This allows creating abstraction layers on top of regular device-tree
+ * resources like regulators, clocks and other nodes connected to the consumer
+ * via phandle.
+ */
+
+static DEFINE_IDA(pwrseq_ida);
+
+/*
+ * Protects the device list on the pwrseq bus from concurrent modifications
+ * but allows simultaneous read-only access.
+ */
+static DECLARE_RWSEM(pwrseq_sem);
+
+/**
+ * struct pwrseq_unit - Private power-sequence unit data.
+ * @ref: Reference count for this object. When it goes to 0, the object is
+ * destroyed.
+ * @name: Name of this target.
+ * @list: Link to siblings on the list of all units of a single sequencer.
+ * @deps: List of units on which this unit depends.
+ * @enable: Callback running the part of the power-on sequence provided by
+ * this unit.
+ * @disable: Callback running the part of the power-off sequence provided
+ * by this unit.
+ * @enable_count: Current number of users that enabled this unit. May be the
+ * consumer of the power sequencer or other units that depend
+ * on this one.
+ */
+struct pwrseq_unit {
+ struct kref ref;
+ const char *name;
+ struct list_head list;
+ struct list_head deps;
+ pwrseq_power_state_func enable;
+ pwrseq_power_state_func disable;
+ unsigned int enable_count;
+};
+
+static struct pwrseq_unit *pwrseq_unit_new(const struct pwrseq_unit_data *data)
+{
+ struct pwrseq_unit *unit;
+
+ unit = kzalloc(sizeof(*unit), GFP_KERNEL);
+ if (!unit)
+ return NULL;
+
+ unit->name = kstrdup_const(data->name, GFP_KERNEL);
+ if (!unit->name) {
+ kfree(unit);
+ return NULL;
+ }
+
+ kref_init(&unit->ref);
+ INIT_LIST_HEAD(&unit->deps);
+ unit->enable = data->enable;
+ unit->disable = data->disable;
+
+ return unit;
+}
+
+static struct pwrseq_unit *pwrseq_unit_incref(struct pwrseq_unit *unit)
+{
+ kref_get(&unit->ref);
+
+ return unit;
+}
+
+static void pwrseq_unit_release(struct kref *ref);
+
+static void pwrseq_unit_decref(struct pwrseq_unit *unit)
+{
+ kref_put(&unit->ref, pwrseq_unit_release);
+}
+
+/**
+ * struct pwrseq_unit_dep - Wrapper around a reference to the unit structure
+ * allowing to keep it on multiple dependency lists
+ * in different units.
+ * @list: Siblings on the list.
+ * @unit: Address of the referenced unit.
+ */
+struct pwrseq_unit_dep {
+ struct list_head list;
+ struct pwrseq_unit *unit;
+};
+
+static struct pwrseq_unit_dep *pwrseq_unit_dep_new(struct pwrseq_unit *unit)
+{
+ struct pwrseq_unit_dep *dep;
+
+ dep = kzalloc(sizeof(*dep), GFP_KERNEL);
+ if (!dep)
+ return NULL;
+
+ dep->unit = unit;
+
+ return dep;
+}
+
+static void pwrseq_unit_dep_free(struct pwrseq_unit_dep *ref)
+{
+ pwrseq_unit_decref(ref->unit);
+ kfree(ref);
+}
+
+static void pwrseq_unit_free_deps(struct list_head *list)
+{
+ struct pwrseq_unit_dep *dep, *next;
+
+ list_for_each_entry_safe(dep, next, list, list) {
+ list_del(&dep->list);
+ pwrseq_unit_dep_free(dep);
+ }
+}
+
+static void pwrseq_unit_release(struct kref *ref)
+{
+ struct pwrseq_unit *unit = container_of(ref, struct pwrseq_unit, ref);
+
+ pwrseq_unit_free_deps(&unit->deps);
+ list_del(&unit->list);
+ kfree_const(unit->name);
+ kfree(unit);
+}
+
+/**
+ * struct pwrseq_target - Private power-sequence target data.
+ * @list: Siblings on the list of all targets exposed by a power sequencer.
+ * @name: Name of the target.
+ * @unit: Final unit for this target.
+ * @post_enable: Callback run after the target unit has been enabled, *after*
+ * the state lock has been released. It's useful for implementing
+ * boot-up delays without blocking other users from powering up
+ * using the same power sequencer.
+ */
+struct pwrseq_target {
+ struct list_head list;
+ const char *name;
+ struct pwrseq_unit *unit;
+ pwrseq_power_state_func post_enable;
+};
+
+static struct pwrseq_target *
+pwrseq_target_new(const struct pwrseq_target_data *data)
+{
+ struct pwrseq_target *target;
+
+ target = kzalloc(sizeof(*target), GFP_KERNEL);
+ if (!target)
+ return NULL;
+
+ target->name = kstrdup_const(data->name, GFP_KERNEL);
+ if (!target->name) {
+ kfree(target);
+ return NULL;
+ }
+
+ target->post_enable = data->post_enable;
+
+ return target;
+}
+
+static void pwrseq_target_free(struct pwrseq_target *target)
+{
+ pwrseq_unit_decref(target->unit);
+ kfree_const(target->name);
+ kfree(target);
+}
+
+/**
+ * struct pwrseq_device - Private power sequencing data.
+ * @dev: Device struct associated with this sequencer.
+ * @id: Device ID.
+ * @owner: Prevents removal of active power sequencing providers.
+ * @rw_lock: Protects the device from being unregistered while in use.
+ * @state_lock: Prevents multiple users running the power sequence at the same
+ * time.
+ * @match: Power sequencer matching callback.
+ * @targets: List of targets exposed by this sequencer.
+ * @units: List of all units supported by this sequencer.
+ */
+struct pwrseq_device {
+ struct device dev;
+ int id;
+ struct module *owner;
+ struct rw_semaphore rw_lock;
+ struct mutex state_lock;
+ pwrseq_match_func match;
+ struct list_head targets;
+ struct list_head units;
+};
+
+static struct pwrseq_device *to_pwrseq_device(struct device *dev)
+{
+ return container_of(dev, struct pwrseq_device, dev);
+}
+
+static struct pwrseq_device *pwrseq_device_get(struct pwrseq_device *pwrseq)
+{
+ get_device(&pwrseq->dev);
+
+ return pwrseq;
+}
+
+static void pwrseq_device_put(struct pwrseq_device *pwrseq)
+{
+ put_device(&pwrseq->dev);
+}
+
+/**
+ * struct pwrseq_desc - Wraps access to the pwrseq_device and ensures that one
+ * user cannot break the reference counting for others.
+ * @pwrseq: Reference to the power sequencing device.
+ * @target: Reference to the target this descriptor allows to control.
+ * @powered_on: Power state set by the holder of the descriptor (not necessarily
+ * corresponding to the actual power state of the device).
+ */
+struct pwrseq_desc {
+ struct pwrseq_device *pwrseq;
+ struct pwrseq_target *target;
+ bool powered_on;
+};
+
+static const struct bus_type pwrseq_bus = {
+ .name = "pwrseq",
+};
+
+static void pwrseq_release(struct device *dev)
+{
+ struct pwrseq_device *pwrseq = to_pwrseq_device(dev);
+ struct pwrseq_target *target;
+
+ list_for_each_entry(target, &pwrseq->targets, list)
+ pwrseq_target_free(target);
+
+ mutex_destroy(&pwrseq->state_lock);
+ ida_free(&pwrseq_ida, pwrseq->id);
+ kfree(pwrseq);
+}
+
+static const struct device_type pwrseq_device_type = {
+ .name = "power_sequencer",
+ .release = pwrseq_release,
+};
+
+static int pwrseq_unit_setup_deps(const struct pwrseq_unit_data **data,
+ struct list_head *dep_list,
+ struct list_head *unit_list,
+ struct radix_tree_root *processed_units)
+{
+ const struct pwrseq_unit_data *pos;
+ struct pwrseq_unit_dep *dep;
+ struct pwrseq_unit *unit;
+ int ret, i;
+
+ for (i = 0; data[i]; i++) {
+ pos = data[i];
+
+ unit = radix_tree_lookup(processed_units, (unsigned long)pos);
+ if (unit) {
+ pwrseq_unit_incref(unit);
+ } else {
+ unit = pwrseq_unit_new(pos);
+ if (!unit)
+ return -ENOMEM;
+
+ if (pos->deps) {
+ ret = pwrseq_unit_setup_deps(pos->deps,
+ &unit->deps,
+ unit_list,
+ processed_units);
+ if (ret) {
+ pwrseq_unit_decref(unit);
+ return ret;
+ }
+ }
+
+ ret = radix_tree_insert(processed_units,
+ (unsigned long)pos, unit);
+ if (ret) {
+ pwrseq_unit_decref(unit);
+ return ret;
+ }
+
+ list_add_tail(&unit->list, unit_list);
+ }
+
+ dep = pwrseq_unit_dep_new(unit);
+ if (!dep) {
+ pwrseq_unit_decref(unit);
+ return -ENOMEM;
+ }
+
+ list_add_tail(&dep->list, dep_list);
+ }
+
+ return 0;
+}
+
+static int pwrseq_target_setup_unit(struct pwrseq_target *target,
+ const struct pwrseq_unit_data *data,
+ struct list_head *unit_list,
+ struct radix_tree_root *processed_units)
+{
+ struct pwrseq_unit *unit;
+ int ret;
+
+ unit = radix_tree_lookup(processed_units, (unsigned long)data);
+ if (unit) {
+ target->unit = pwrseq_unit_incref(unit);
+ return 0;
+ }
+
+ unit = pwrseq_unit_new(data);
+ if (!unit)
+ return -ENOMEM;
+
+ ret = pwrseq_unit_setup_deps(data->deps, &unit->deps, unit_list,
+ processed_units);
+ if (ret) {
+ pwrseq_unit_decref(unit);
+ return ret;
+ }
+
+ ret = radix_tree_insert(processed_units, (unsigned long)data, unit);
+ if (ret) {
+ pwrseq_unit_decref(unit);
+ return ret;
+ }
+
+ target->unit = unit;
+ list_add_tail(&unit->list, unit_list);
+
+ return 0;
+}
+
+static int pwrseq_do_setup_targets(const struct pwrseq_target_data **data,
+ struct pwrseq_device *pwrseq,
+ struct radix_tree_root *processed_units)
+{
+ const struct pwrseq_target_data *pos;
+ struct pwrseq_target *target;
+ int ret, i;
+
+ for (i = 0; data[i]; i++) {
+ pos = data[i];
+
+ target = pwrseq_target_new(pos);
+ if (!target)
+ return -ENOMEM;
+
+ ret = pwrseq_target_setup_unit(target, pos->unit,
+ &pwrseq->units,
+ processed_units);
+ if (ret) {
+ pwrseq_target_free(target);
+ return ret;
+ }
+
+ list_add_tail(&target->list, &pwrseq->targets);
+ }
+
+ return 0;
+}
+
+static int pwrseq_setup_targets(const struct pwrseq_target_data **targets,
+ struct pwrseq_device *pwrseq)
+{
+ struct radix_tree_root processed_units;
+ struct radix_tree_iter iter;
+ void __rcu **slot;
+ int ret;
+
+ INIT_RADIX_TREE(&processed_units, GFP_KERNEL);
+ ret = pwrseq_do_setup_targets(targets, pwrseq, &processed_units);
+ radix_tree_for_each_slot(slot, &processed_units, &iter, 0)
+ radix_tree_delete(&processed_units, iter.index);
+
+ return ret;
+}
+
+/**
+ * pwrseq_device_register() - Register a new power sequencer.
+ * @config: Configuration of the new power sequencing device.
+ *
+ * The config structure is only used during the call and can be freed after
+ * the function returns. The config structure *must* have the parent device
+ * as well as the match() callback and at least one target set.
+ *
+ * Returns:
+ * Returns the address of the new pwrseq device or ERR_PTR() on failure.
+ */
+struct pwrseq_device *
+pwrseq_device_register(const struct pwrseq_config *config)
+{
+ struct pwrseq_device *pwrseq;
+ int ret;
+
+ if (!config->parent || !config->match || !config->targets ||
+ !config->targets[0])
+ return ERR_PTR(-EINVAL);
+
+ pwrseq = kzalloc(sizeof(*pwrseq), GFP_KERNEL);
+ if (!pwrseq)
+ return ERR_PTR(-ENOMEM);
+
+ pwrseq->dev.type = &pwrseq_device_type;
+ pwrseq->dev.bus = &pwrseq_bus;
+ pwrseq->dev.parent = config->parent;
+ device_set_node(&pwrseq->dev, dev_fwnode(config->parent));
+ dev_set_drvdata(&pwrseq->dev, config->drvdata);
+
+ pwrseq->id = ida_alloc(&pwrseq_ida, GFP_KERNEL);
+ if (pwrseq->id < 0) {
+ kfree(pwrseq);
+ return ERR_PTR(pwrseq->id);
+ }
+
+ /*
+ * From this point onwards the device's release() callback is
+ * responsible for freeing resources.
+ */
+ device_initialize(&pwrseq->dev);
+
+ ret = dev_set_name(&pwrseq->dev, "pwrseq.%d", pwrseq->id);
+ if (ret)
+ goto err_put_pwrseq;
+
+ pwrseq->owner = config->owner ?: THIS_MODULE;
+ pwrseq->match = config->match;
+
+ init_rwsem(&pwrseq->rw_lock);
+ mutex_init(&pwrseq->state_lock);
+ INIT_LIST_HEAD(&pwrseq->targets);
+ INIT_LIST_HEAD(&pwrseq->units);
+
+ ret = pwrseq_setup_targets(config->targets, pwrseq);
+ if (ret)
+ goto err_put_pwrseq;
+
+ scoped_guard(rwsem_write, &pwrseq_sem) {
+ ret = device_add(&pwrseq->dev);
+ if (ret)
+ goto err_put_pwrseq;
+ }
+
+ return pwrseq;
+
+err_put_pwrseq:
+ pwrseq_device_put(pwrseq);
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(pwrseq_device_register);
+
+/**
+ * pwrseq_device_unregister() - Unregister the power sequencer.
+ * @pwrseq: Power sequencer to unregister.
+ */
+void pwrseq_device_unregister(struct pwrseq_device *pwrseq)
+{
+ struct device *dev = &pwrseq->dev;
+ struct pwrseq_target *target;
+
+ scoped_guard(mutex, &pwrseq->state_lock) {
+ guard(rwsem_write)(&pwrseq->rw_lock);
+
+ list_for_each_entry(target, &pwrseq->targets, list)
+ WARN_ONCE(target->unit->enable_count,
+ "REMOVING POWER SEQUENCER WITH ACTIVE USERS\n");
+
+ guard(rwsem_write)(&pwrseq_sem);
+
+ device_del(dev);
+ }
+
+ pwrseq_device_put(pwrseq);
+}
+EXPORT_SYMBOL_GPL(pwrseq_device_unregister);
+
+static void devm_pwrseq_device_unregister(void *data)
+{
+ struct pwrseq_device *pwrseq = data;
+
+ pwrseq_device_unregister(pwrseq);
+}
+
+/**
+ * devm_pwrseq_device_register() - Managed variant of pwrseq_device_register().
+ * @dev: Managing device.
+ * @config: Configuration of the new power sequencing device.
+ *
+ * Returns:
+ * Returns the address of the new pwrseq device or ERR_PTR() on failure.
+ */
+struct pwrseq_device *
+devm_pwrseq_device_register(struct device *dev,
+ const struct pwrseq_config *config)
+{
+ struct pwrseq_device *pwrseq;
+ int ret;
+
+ pwrseq = pwrseq_device_register(config);
+ if (IS_ERR(pwrseq))
+ return pwrseq;
+
+ ret = devm_add_action_or_reset(dev, devm_pwrseq_device_unregister,
+ pwrseq);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return pwrseq;
+}
+EXPORT_SYMBOL_GPL(devm_pwrseq_device_register);
+
+/**
+ * pwrseq_device_get_drvdata() - Get the driver private data associated with
+ * this sequencer.
+ * @pwrseq: Power sequencer object.
+ *
+ * Returns:
+ * Address of the private driver data.
+ */
+void *pwrseq_device_get_drvdata(struct pwrseq_device *pwrseq)
+{
+ return dev_get_drvdata(&pwrseq->dev);
+}
+EXPORT_SYMBOL_GPL(pwrseq_device_get_drvdata);
+
+struct pwrseq_match_data {
+ struct pwrseq_desc *desc;
+ struct device *dev;
+ const char *target;
+};
+
+static int pwrseq_match_device(struct device *pwrseq_dev, void *data)
+{
+ struct pwrseq_device *pwrseq = to_pwrseq_device(pwrseq_dev);
+ struct pwrseq_match_data *match_data = data;
+ struct pwrseq_target *target;
+ int ret;
+
+ guard(rwsem_read)(&pwrseq->rw_lock);
+ if (!device_is_registered(&pwrseq->dev))
+ return 0;
+
+ ret = pwrseq->match(pwrseq, match_data->dev);
+ if (ret <= 0)
+ return ret;
+
+ /* We got the matching device, let's find the right target. */
+ list_for_each_entry(target, &pwrseq->targets, list) {
+ if (strcmp(target->name, match_data->target))
+ continue;
+
+ match_data->desc->target = target;
+ }
+
+ /*
+ * This device does not have this target. No point in deferring as it
+ * will not get a new target dynamically later.
+ */
+ if (!match_data->desc->target)
+ return -ENOENT;
+
+ if (!try_module_get(pwrseq->owner))
+ return -EPROBE_DEFER;
+
+ match_data->desc->pwrseq = pwrseq_device_get(pwrseq);
+
+ return 1;
+}
+
+/**
+ * pwrseq_get() - Get the power sequencer associated with this device.
+ * @dev: Device for which to get the sequencer.
+ * @target: Name of the target exposed by the sequencer this device wants to
+ * reach.
+ *
+ * Returns:
+ * New power sequencer descriptor for use by the consumer driver or ERR_PTR()
+ * on failure.
+ */
+struct pwrseq_desc *pwrseq_get(struct device *dev, const char *target)
+{
+ struct pwrseq_match_data match_data;
+ int ret;
+
+ struct pwrseq_desc *desc __free(kfree) = kzalloc(sizeof(*desc),
+ GFP_KERNEL);
+ if (!desc)
+ return ERR_PTR(-ENOMEM);
+
+ match_data.desc = desc;
+ match_data.dev = dev;
+ match_data.target = target;
+
+ guard(rwsem_read)(&pwrseq_sem);
+
+ ret = bus_for_each_dev(&pwrseq_bus, NULL, &match_data,
+ pwrseq_match_device);
+ if (ret < 0)
+ return ERR_PTR(ret);
+ if (ret == 0)
+ /* No device matched. */
+ return ERR_PTR(-EPROBE_DEFER);
+
+ return no_free_ptr(desc);
+}
+EXPORT_SYMBOL_GPL(pwrseq_get);
+
+/**
+ * pwrseq_put() - Release the power sequencer descriptor.
+ * @desc: Descriptor to release.
+ */
+void pwrseq_put(struct pwrseq_desc *desc)
+{
+ struct pwrseq_device *pwrseq;
+
+ if (!desc)
+ return;
+
+ pwrseq = desc->pwrseq;
+
+ if (desc->powered_on)
+ pwrseq_power_off(desc);
+
+ kfree(desc);
+ module_put(pwrseq->owner);
+ pwrseq_device_put(pwrseq);
+}
+EXPORT_SYMBOL_GPL(pwrseq_put);
+
+static void devm_pwrseq_put(void *data)
+{
+ struct pwrseq_desc *desc = data;
+
+ pwrseq_put(desc);
+}
+
+/**
+ * devm_pwrseq_get() - Managed variant of pwrseq_get().
+ * @dev: Device for which to get the sequencer and which also manages its
+ * lifetime.
+ * @target: Name of the target exposed by the sequencer this device wants to
+ * reach.
+ *
+ * Returns:
+ * New power sequencer descriptor for use by the consumer driver or ERR_PTR()
+ * on failure.
+ */
+struct pwrseq_desc *devm_pwrseq_get(struct device *dev, const char *target)
+{
+ struct pwrseq_desc *desc;
+ int ret;
+
+ desc = pwrseq_get(dev, target);
+ if (IS_ERR(desc))
+ return desc;
+
+ ret = devm_add_action_or_reset(dev, devm_pwrseq_put, desc);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return desc;
+}
+EXPORT_SYMBOL_GPL(devm_pwrseq_get);
+
+static int pwrseq_unit_enable(struct pwrseq_device *pwrseq,
+ struct pwrseq_unit *target);
+static int pwrseq_unit_disable(struct pwrseq_device *pwrseq,
+ struct pwrseq_unit *target);
+
+static int pwrseq_unit_enable_deps(struct pwrseq_device *pwrseq,
+ struct list_head *list)
+{
+ struct pwrseq_unit_dep *pos;
+ int ret = 0;
+
+ list_for_each_entry(pos, list, list) {
+ ret = pwrseq_unit_enable(pwrseq, pos->unit);
+ if (ret) {
+ list_for_each_entry_continue_reverse(pos, list, list)
+ pwrseq_unit_disable(pwrseq, pos->unit);
+ break;
+ }
+ }
+
+ return ret;
+}
+
+static int pwrseq_unit_disable_deps(struct pwrseq_device *pwrseq,
+ struct list_head *list)
+{
+ struct pwrseq_unit_dep *pos;
+ int ret = 0;
+
+ list_for_each_entry_reverse(pos, list, list) {
+ ret = pwrseq_unit_disable(pwrseq, pos->unit);
+ if (ret) {
+ list_for_each_entry_continue(pos, list, list)
+ pwrseq_unit_enable(pwrseq, pos->unit);
+ break;
+ }
+ }
+
+ return ret;
+}
+
+static int pwrseq_unit_enable(struct pwrseq_device *pwrseq,
+ struct pwrseq_unit *unit)
+{
+ int ret;
+
+ if (unit->enable_count != 0) {
+ unit->enable_count++;
+ return 0;
+ }
+
+ ret = pwrseq_unit_enable_deps(pwrseq, &unit->deps);
+ if (ret) {
+ dev_err(&pwrseq->dev,
+ "Failed to enable dependencies before power-on for target '%s': %d\n",
+ unit->name, ret);
+ return ret;
+ }
+
+ if (unit->enable) {
+ ret = unit->enable(pwrseq);
+ if (ret) {
+ dev_err(&pwrseq->dev,
+ "Failed to enable target '%s': %d\n",
+ unit->name, ret);
+ pwrseq_unit_disable_deps(pwrseq, &unit->deps);
+ return ret;
+ }
+ }
+
+ unit->enable_count++;
+
+ return 0;
+}
+
+static int pwrseq_unit_disable(struct pwrseq_device *pwrseq,
+ struct pwrseq_unit *unit)
+{
+ int ret;
+
+ if (unit->enable_count == 0) {
+ WARN_ONCE(1, "Unmatched power-off for target '%s'\n",
+ unit->name);
+ return -EBUSY;
+ }
+
+ if (unit->enable_count != 1) {
+ unit->enable_count--;
+ return 0;
+ }
+
+ if (unit->disable) {
+ ret = unit->disable(pwrseq);
+ if (ret) {
+ dev_err(&pwrseq->dev,
+ "Failed to disable target '%s': %d\n",
+ unit->name, ret);
+ return ret;
+ }
+ }
+
+ ret = pwrseq_unit_disable_deps(pwrseq, &unit->deps);
+ if (ret) {
+ dev_err(&pwrseq->dev,
+ "Failed to disable dependencies after power-off for target '%s': %d\n",
+ unit->name, ret);
+ if (unit->enable)
+ unit->enable(pwrseq);
+ return ret;
+ }
+
+ unit->enable_count--;
+
+ return 0;
+}
+
+/**
+ * pwrseq_power_on() - Issue a power-on request on behalf of the consumer
+ * device.
+ * @desc: Descriptor referencing the power sequencer.
+ *
+ * This function tells the power sequencer that the consumer wants to be
+ * powered-up. The sequencer may already have powered-up the device in which
+ * case the function returns 0. If the power-up sequence is already in
+ * progress, the function will block until it's done and return 0. If this is
+ * the first request, the device will be powered up.
+ *
+ * Returns:
+ * 0 on success, negative error number on failure.
+ */
+int pwrseq_power_on(struct pwrseq_desc *desc)
+{
+ struct pwrseq_device *pwrseq;
+ struct pwrseq_target *target;
+ struct pwrseq_unit *unit;
+ int ret;
+
+ might_sleep();
+
+ if (!desc || desc->powered_on)
+ return 0;
+
+ pwrseq = desc->pwrseq;
+ target = desc->target;
+ unit = target->unit;
+
+ guard(rwsem_read)(&pwrseq->rw_lock);
+ if (!device_is_registered(&pwrseq->dev))
+ return -ENODEV;
+
+ scoped_guard(mutex, &pwrseq->state_lock) {
+ ret = pwrseq_unit_enable(pwrseq, unit);
+ if (!ret)
+ desc->powered_on = true;
+ }
+
+ if (target->post_enable) {
+ ret = target->post_enable(pwrseq);
+ if (ret) {
+ pwrseq_unit_disable(pwrseq, unit);
+ desc->powered_on = false;
+ }
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pwrseq_power_on);
+
+/**
+ * pwrseq_power_off() - Issue a power-off request on behalf of the consumer
+ * device.
+ * @desc: Descriptor referencing the power sequencer.
+ *
+ * This undoes the effects of pwrseq_power_on(). It issues a power-off request
+ * on behalf of the consumer and when the last remaining user does so, the
+ * power-down sequence will be started. If one is in progress, the function
+ * will block until it's complete and then return.
+ *
+ * Returns:
+ * 0 on success, negative error number on failure.
+ */
+int pwrseq_power_off(struct pwrseq_desc *desc)
+{
+ struct pwrseq_device *pwrseq;
+ struct pwrseq_unit *unit;
+ int ret;
+
+ might_sleep();
+
+ if (!desc || !desc->powered_on)
+ return 0;
+
+ pwrseq = desc->pwrseq;
+ unit = desc->target->unit;
+
+ guard(rwsem_read)(&pwrseq->rw_lock);
+ if (!device_is_registered(&pwrseq->dev))
+ return -ENODEV;
+
+ guard(mutex)(&pwrseq->state_lock);
+
+ ret = pwrseq_unit_disable(pwrseq, unit);
+ if (!ret)
+ desc->powered_on = false;
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pwrseq_power_off);
+
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+
+struct pwrseq_debugfs_count_ctx {
+ struct device *dev;
+ loff_t index;
+};
+
+static int pwrseq_debugfs_seq_count(struct device *dev, void *data)
+{
+ struct pwrseq_debugfs_count_ctx *ctx = data;
+
+ ctx->dev = dev;
+
+ return ctx->index-- ? 0 : 1;
+}
+
+static void *pwrseq_debugfs_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ struct pwrseq_debugfs_count_ctx ctx;
+
+ ctx.dev = NULL;
+ ctx.index = *pos;
+
+ /*
+ * We're holding the lock for the entire printout so no need to fiddle
+ * with device reference count.
+ */
+ down_read(&pwrseq_sem);
+
+ bus_for_each_dev(&pwrseq_bus, NULL, &ctx, pwrseq_debugfs_seq_count);
+ if (!ctx.index)
+ return NULL;
+
+ return ctx.dev;
+}
+
+static void *pwrseq_debugfs_seq_next(struct seq_file *seq, void *data,
+ loff_t *pos)
+{
+ struct device *curr = data;
+
+ ++*pos;
+
+ struct device *next __free(put_device) =
+ bus_find_next_device(&pwrseq_bus, curr);
+ return next;
+}
+
+static void pwrseq_debugfs_seq_show_target(struct seq_file *seq,
+ struct pwrseq_target *target)
+{
+ seq_printf(seq, " target: [%s] (target unit: [%s])\n",
+ target->name, target->unit->name);
+}
+
+static void pwrseq_debugfs_seq_show_unit(struct seq_file *seq,
+ struct pwrseq_unit *unit)
+{
+ struct pwrseq_unit_dep *ref;
+
+ seq_printf(seq, " unit: [%s] - enable count: %u\n",
+ unit->name, unit->enable_count);
+
+ if (list_empty(&unit->deps))
+ return;
+
+ seq_puts(seq, " dependencies:\n");
+ list_for_each_entry(ref, &unit->deps, list)
+ seq_printf(seq, " [%s]\n", ref->unit->name);
+}
+
+static int pwrseq_debugfs_seq_show(struct seq_file *seq, void *data)
+{
+ struct device *dev = data;
+ struct pwrseq_device *pwrseq = to_pwrseq_device(dev);
+ struct pwrseq_target *target;
+ struct pwrseq_unit *unit;
+
+ seq_printf(seq, "%s:\n", dev_name(dev));
+
+ seq_puts(seq, " targets:\n");
+ list_for_each_entry(target, &pwrseq->targets, list)
+ pwrseq_debugfs_seq_show_target(seq, target);
+
+ seq_puts(seq, " units:\n");
+ list_for_each_entry(unit, &pwrseq->units, list)
+ pwrseq_debugfs_seq_show_unit(seq, unit);
+
+ return 0;
+}
+
+static void pwrseq_debugfs_seq_stop(struct seq_file *seq, void *data)
+{
+ up_read(&pwrseq_sem);
+}
+
+static const struct seq_operations pwrseq_debugfs_sops = {
+ .start = pwrseq_debugfs_seq_start,
+ .next = pwrseq_debugfs_seq_next,
+ .show = pwrseq_debugfs_seq_show,
+ .stop = pwrseq_debugfs_seq_stop,
+};
+DEFINE_SEQ_ATTRIBUTE(pwrseq_debugfs);
+
+static struct dentry *pwrseq_debugfs_dentry;
+
+#endif /* CONFIG_DEBUG_FS */
+
+static int __init pwrseq_init(void)
+{
+ int ret;
+
+ ret = bus_register(&pwrseq_bus);
+ if (ret) {
+ pr_err("Failed to register the power sequencer bus\n");
+ return ret;
+ }
+
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+ pwrseq_debugfs_dentry = debugfs_create_file("pwrseq", 0444, NULL, NULL,
+ &pwrseq_debugfs_fops);
+#endif /* CONFIG_DEBUG_FS */
+
+ return 0;
+}
+subsys_initcall(pwrseq_init);
+
+static void __exit pwrseq_exit(void)
+{
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+ debugfs_remove_recursive(pwrseq_debugfs_dentry);
+#endif /* CONFIG_DEBUG_FS */
+
+ bus_unregister(&pwrseq_bus);
+}
+module_exit(pwrseq_exit);
+
+MODULE_AUTHOR("Bartosz Golaszewski <[email protected]>");
+MODULE_DESCRIPTION("Power Sequencing subsystem core");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/pwrseq/consumer.h b/include/linux/pwrseq/consumer.h
new file mode 100644
index 000000000000..7d583b4f266e
--- /dev/null
+++ b/include/linux/pwrseq/consumer.h
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2024 Linaro Ltd.
+ */
+
+#ifndef __POWER_SEQUENCING_CONSUMER_H__
+#define __POWER_SEQUENCING_CONSUMER_H__
+
+#include <linux/err.h>
+
+struct device;
+struct pwrseq_desc;
+
+#if IS_ENABLED(CONFIG_POWER_SEQUENCING)
+
+struct pwrseq_desc * __must_check
+pwrseq_get(struct device *dev, const char *target);
+void pwrseq_put(struct pwrseq_desc *desc);
+
+struct pwrseq_desc * __must_check
+devm_pwrseq_get(struct device *dev, const char *target);
+
+int pwrseq_power_on(struct pwrseq_desc *desc);
+int pwrseq_power_off(struct pwrseq_desc *desc);
+
+#else /* CONFIG_POWER_SEQUENCING */
+
+static inline struct pwrseq_desc * __must_check
+pwrseq_get(struct device *dev, const char *target)
+{
+ return ERR_PTR(-ENOSYS);
+}
+
+static inline void pwrseq_put(struct pwrseq_desc *desc)
+{
+}
+
+static inline struct pwrseq_desc * __must_check
+devm_pwrseq_get(struct device *dev, const char *target)
+{
+ return ERR_PTR(-ENOSYS);
+}
+
+static inline int pwrseq_power_on(struct pwrseq_desc *desc)
+{
+ return -ENOSYS;
+}
+
+static inline int pwrseq_power_off(struct pwrseq_desc *desc)
+{
+ return -ENOSYS;
+}
+
+#endif /* CONFIG_POWER_SEQUENCING */
+
+#endif /* __POWER_SEQUENCING_CONSUMER_H__ */
diff --git a/include/linux/pwrseq/provider.h b/include/linux/pwrseq/provider.h
new file mode 100644
index 000000000000..e627ed2f4d91
--- /dev/null
+++ b/include/linux/pwrseq/provider.h
@@ -0,0 +1,75 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2024 Linaro Ltd.
+ */
+
+#ifndef __POWER_SEQUENCING_PROVIDER_H__
+#define __POWER_SEQUENCING_PROVIDER_H__
+
+struct device;
+struct module;
+struct pwrseq_device;
+
+typedef int (*pwrseq_power_state_func)(struct pwrseq_device *);
+typedef int (*pwrseq_match_func)(struct pwrseq_device *, struct device *);
+
+/**
+ * struct pwrseq_unit_data - Configuration of a single power sequencing
+ * unit.
+ * @name: Name of the unit.
+ * @deps: Units that must be enabled before this one and disabled after it
+ * in the order they come in this array.
+ * @enable: Callback running the part of the power-on sequence provided by
+ * this unit.
+ * @disable: Callback running the part of the power-off sequence provided
+ * by this unit.
+ */
+struct pwrseq_unit_data {
+ const char *name;
+ const struct pwrseq_unit_data **deps;
+ pwrseq_power_state_func enable;
+ pwrseq_power_state_func disable;
+};
+
+/**
+ * struct pwrseq_target_data - Configuration of a power sequencing target.
+ * @name: Name of the target.
+ * @unit: Final unit that this target must reach in order to be considered
+ * enabled.
+ * @post_enable: Callback run after the target unit has been enabled, *after*
+ * the state lock has been released. It's useful for implementing
+ * boot-up delays without blocking other users from powering up
+ * using the same power sequencer.
+ */
+struct pwrseq_target_data {
+ const char *name;
+ const struct pwrseq_unit_data *unit;
+ pwrseq_power_state_func post_enable;
+};
+
+/**
+ * struct pwrseq_config - Configuration used for registering a new provider.
+ * @parent: Parent device for the sequencer. Must be set.
+ * @owner: Module providing this device.
+ * @drvdata: Private driver data.
+ * @match: Provider callback used to match the consumer device to the sequencer.
+ * @targets: Array of targets for this power sequencer. Must be NULL-terminated.
+ */
+struct pwrseq_config {
+ struct device *parent;
+ struct module *owner;
+ void *drvdata;
+ pwrseq_match_func match;
+ const struct pwrseq_target_data **targets;
+};
+
+struct pwrseq_device *
+pwrseq_device_register(const struct pwrseq_config *config);
+void pwrseq_device_unregister(struct pwrseq_device *pwrseq);
+struct pwrseq_device *
+devm_pwrseq_device_register(struct device *dev,
+ const struct pwrseq_config *config);
+
+void *pwrseq_device_get_drvdata(struct pwrseq_device *pwrseq);
+
+#endif /* __POWER_SEQUENCING_PROVIDER_H__ */
--
2.40.1
From: Bartosz Golaszewski <[email protected]>
Add a PCI power control driver that's capable of correctly powering up
devices using the power sequencing subsystem. The first user of this
driver is the ath11k module on QCA6390.
Signed-off-by: Bartosz Golaszewski <[email protected]>
---
drivers/pci/pwrctl/Kconfig | 9 +++
drivers/pci/pwrctl/Makefile | 2 +
drivers/pci/pwrctl/pci-pwrctl-pwrseq.c | 89 ++++++++++++++++++++++++++
3 files changed, 100 insertions(+)
create mode 100644 drivers/pci/pwrctl/pci-pwrctl-pwrseq.c
diff --git a/drivers/pci/pwrctl/Kconfig b/drivers/pci/pwrctl/Kconfig
index 96195395af69..eb126225eb9f 100644
--- a/drivers/pci/pwrctl/Kconfig
+++ b/drivers/pci/pwrctl/Kconfig
@@ -5,4 +5,13 @@ menu "PCI Power control drivers"
config PCI_PWRCTL
tristate
+config PCI_PWRCTL_PWRSEQ
+ tristate "PCI Power Control driver using the Power Sequencing subsystem"
+ select POWER_SEQUENCING
+ select PCI_PWRCTL
+ default m if (ATH11K_PCI && ARCH_QCOM)
+ help
+ Enable support for the PCI power control driver for device
+ drivers using the Power Sequencing subsystem.
+
endmenu
diff --git a/drivers/pci/pwrctl/Makefile b/drivers/pci/pwrctl/Makefile
index 52ae0640ef7b..d308aae4800c 100644
--- a/drivers/pci/pwrctl/Makefile
+++ b/drivers/pci/pwrctl/Makefile
@@ -2,3 +2,5 @@
obj-$(CONFIG_PCI_PWRCTL) += pci-pwrctl-core.o
pci-pwrctl-core-y := core.o
+
+obj-$(CONFIG_PCI_PWRCTL_PWRSEQ) += pci-pwrctl-pwrseq.o
diff --git a/drivers/pci/pwrctl/pci-pwrctl-pwrseq.c b/drivers/pci/pwrctl/pci-pwrctl-pwrseq.c
new file mode 100644
index 000000000000..c7a113a76c0c
--- /dev/null
+++ b/drivers/pci/pwrctl/pci-pwrctl-pwrseq.c
@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2024 Linaro Ltd.
+ */
+
+#include <linux/device.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pci-pwrctl.h>
+#include <linux/platform_device.h>
+#include <linux/pwrseq/consumer.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+struct pci_pwrctl_pwrseq_data {
+ struct pci_pwrctl ctx;
+ struct pwrseq_desc *pwrseq;
+};
+
+static void devm_pci_pwrctl_pwrseq_power_off(void *data)
+{
+ struct pwrseq_desc *pwrseq = data;
+
+ pwrseq_power_off(pwrseq);
+}
+
+static int pci_pwrctl_pwrseq_probe(struct platform_device *pdev)
+{
+ struct pci_pwrctl_pwrseq_data *data;
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->pwrseq = devm_pwrseq_get(dev, of_device_get_match_data(dev));
+ if (IS_ERR(data->pwrseq))
+ return dev_err_probe(dev, PTR_ERR(data->pwrseq),
+ "Failed to get the power sequencer\n");
+
+ ret = pwrseq_power_on(data->pwrseq);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to power-on the device\n");
+
+ ret = devm_add_action_or_reset(dev, devm_pci_pwrctl_pwrseq_power_off,
+ data->pwrseq);
+ if (ret)
+ return ret;
+
+ data->ctx.dev = dev;
+
+ ret = devm_pci_pwrctl_device_set_ready(dev, &data->ctx);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to register the pwrctl wrapper\n");
+
+ return 0;
+}
+
+static const struct of_device_id pci_pwrctl_pwrseq_of_match[] = {
+ {
+ /* ATH11K in QCA6390 package. */
+ .compatible = "pci17cb,1101",
+ .data = "wlan",
+ },
+ {
+ /* ATH12K in WCN7850 package. */
+ .compatible = "pci17cb,1107",
+ .data = "wlan",
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, pci_pwrctl_pwrseq_of_match);
+
+static struct platform_driver pci_pwrctl_pwrseq_driver = {
+ .driver = {
+ .name = "pci-pwrctl-pwrseq",
+ .of_match_table = pci_pwrctl_pwrseq_of_match,
+ },
+ .probe = pci_pwrctl_pwrseq_probe,
+};
+module_platform_driver(pci_pwrctl_pwrseq_driver);
+
+MODULE_AUTHOR("Bartosz Golaszewski <[email protected]>");
+MODULE_DESCRIPTION("Generic PCI Power Control module for power sequenced devices");
+MODULE_LICENSE("GPL");
--
2.40.1
Bartosz Golaszewski <[email protected]> writes:
> From: Bartosz Golaszewski <[email protected]>
>
> Add device-tree bindings for the ATH12K module found in the WCN7850
> package.
>
> Signed-off-by: Bartosz Golaszewski <[email protected]>
> ---
> .../bindings/net/wireless/qcom,ath12k.yaml | 100 ++++++++++++++++++
> 1 file changed, 100 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/net/wireless/qcom,ath12k.yaml
>
> diff --git a/Documentation/devicetree/bindings/net/wireless/qcom,ath12k.yaml b/Documentation/devicetree/bindings/net/wireless/qcom,ath12k.yaml
> new file mode 100644
> index 000000000000..c0aad4815953
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/wireless/qcom,ath12k.yaml
> @@ -0,0 +1,100 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright (c) 2024 Linaro Limited
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/net/wireless/qcom,ath12k.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm Technologies ath12k wireless devices (PCIe)
> +
> +maintainers:
> + - Bartosz Golaszewski <[email protected]>
IMHO it would be better to have just driver maintainers listed here.
> + - Jeff Johnson <[email protected]>
> + - Kalle Valo <[email protected]>
> +
> +description:
> + Qualcomm Technologies IEEE 802.11ax PCIe devices.
> +
> +properties:
> + compatible:
> + enum:
> + - pci17cb,1107 # WCN7850
> +
> + reg:
> + maxItems: 1
> +
> + vddaon-supply:
> + description: VDD_AON supply regulator handle
> +
> + vddwlcx-supply:
> + description: VDD_WLCX supply regulator handle
> +
> + vddwlmx-supply:
> + description: VDD_WLMX supply regulator handle
> +
> + vddrfacmn-supply:
> + description: VDD_RFA_CMN supply regulator handle
> +
> + vddrfa0p8-supply:
> + description: VDD_RFA_0P8 supply regulator handle
> +
> + vddrfa1p2-supply:
> + description: VDD_RFA_1P2 supply regulator handle
> +
> + vddrfa1p8-supply:
> + description: VDD_RFA_1P8 supply regulator handle
> +
> + vddpcie0p9-supply:
> + description: VDD_PCIE_0P9 supply regulator handle
> +
> + vddpcie1p8-supply:
> + description: VDD_PCIE_1P8 supply regulator handle
> +
> +required:
> + - compatible
> + - reg
> + - vddaon-supply
> + - vddwlcx-supply
> + - vddwlmx-supply
> + - vddrfacmn-supply
> + - vddrfa0p8-supply
> + - vddrfa1p2-supply
> + - vddrfa1p8-supply
> + - vddpcie0p9-supply
> + - vddpcie1p8-supply
Same comment here as in patch 4. There are also ath12k PCI devices which
don't need DT at all. I don't know if that should be reflected in the
bindings doc but I want to point out this.
--
https://patchwork.kernel.org/project/linux-wireless/list/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
From: Bartosz Golaszewski <[email protected]>
Some PCI devices must be powered-on before they can be detected on the
bus. Introduce a simple framework reusing the existing PCI OF
infrastructure.
The way this works is: a DT node representing a PCI device connected to
the port can be matched against its power control platform driver. If
the match succeeds, the driver is responsible for powering-up the device
and calling pcie_pwrctl_device_set_ready() which will trigger a PCI bus
rescan as well as subscribe to PCI bus notifications.
When the device is detected and created, we'll make it consume the same
DT node that the platform device did. When the device is bound, we'll
create a device link between it and the parent power control device.
Signed-off-by: Bartosz Golaszewski <[email protected]>
---
drivers/pci/Kconfig | 1 +
drivers/pci/Makefile | 1 +
drivers/pci/pwrctl/Kconfig | 8 +++
drivers/pci/pwrctl/Makefile | 4 ++
drivers/pci/pwrctl/core.c | 136 ++++++++++++++++++++++++++++++++++++
include/linux/pci-pwrctl.h | 51 ++++++++++++++
6 files changed, 201 insertions(+)
create mode 100644 drivers/pci/pwrctl/Kconfig
create mode 100644 drivers/pci/pwrctl/Makefile
create mode 100644 drivers/pci/pwrctl/core.c
create mode 100644 include/linux/pci-pwrctl.h
diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index d35001589d88..aa4d1833f442 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -296,5 +296,6 @@ source "drivers/pci/hotplug/Kconfig"
source "drivers/pci/controller/Kconfig"
source "drivers/pci/endpoint/Kconfig"
source "drivers/pci/switch/Kconfig"
+source "drivers/pci/pwrctl/Kconfig"
endif
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index 175302036890..8ddad57934a6 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_PCI) += access.o bus.o probe.o host-bridge.o \
obj-$(CONFIG_PCI) += msi/
obj-$(CONFIG_PCI) += pcie/
+obj-$(CONFIG_PCI) += pwrctl/
ifdef CONFIG_PCI
obj-$(CONFIG_PROC_FS) += proc.o
diff --git a/drivers/pci/pwrctl/Kconfig b/drivers/pci/pwrctl/Kconfig
new file mode 100644
index 000000000000..96195395af69
--- /dev/null
+++ b/drivers/pci/pwrctl/Kconfig
@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+menu "PCI Power control drivers"
+
+config PCI_PWRCTL
+ tristate
+
+endmenu
diff --git a/drivers/pci/pwrctl/Makefile b/drivers/pci/pwrctl/Makefile
new file mode 100644
index 000000000000..52ae0640ef7b
--- /dev/null
+++ b/drivers/pci/pwrctl/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+obj-$(CONFIG_PCI_PWRCTL) += pci-pwrctl-core.o
+pci-pwrctl-core-y := core.o
diff --git a/drivers/pci/pwrctl/core.c b/drivers/pci/pwrctl/core.c
new file mode 100644
index 000000000000..11bd19519841
--- /dev/null
+++ b/drivers/pci/pwrctl/core.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2024 Linaro Ltd.
+ */
+
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/pci-pwrctl.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+
+static int pci_pwrctl_notify(struct notifier_block *nb, unsigned long action,
+ void *data)
+{
+ struct pci_pwrctl *pwrctl = container_of(nb, struct pci_pwrctl, nb);
+ struct device *dev = data;
+
+ if (dev_fwnode(dev) != dev_fwnode(pwrctl->dev))
+ return NOTIFY_DONE;
+
+ switch (action) {
+ case BUS_NOTIFY_ADD_DEVICE:
+ /*
+ * We will have two struct device objects bound to two different
+ * drivers on different buses but consuming the same DT node. We
+ * must not bind the pins twice in this case but only once for
+ * the first device to be added.
+ *
+ * If we got here then the PCI device is the second after the
+ * power control platform device. Mark its OF node as reused.
+ */
+ dev->of_node_reused = true;
+ break;
+ case BUS_NOTIFY_BOUND_DRIVER:
+ pwrctl->link = device_link_add(dev, pwrctl->dev,
+ DL_FLAG_AUTOREMOVE_CONSUMER);
+ if (!pwrctl->link)
+ dev_err(pwrctl->dev, "Failed to add device link\n");
+ break;
+ case BUS_NOTIFY_UNBOUND_DRIVER:
+ if (pwrctl->link)
+ device_link_del(pwrctl->link);
+ break;
+ }
+
+ return NOTIFY_DONE;
+}
+
+/**
+ * pci_pwrctl_device_set_ready() - Notify the pwrctl subsystem that the PCI
+ * device is powered-up and ready to be detected.
+ *
+ * @pwrctl: PCI power control data
+ *
+ * Returns:
+ * 0 on success, negative error number on error.
+ *
+ * Note:
+ * This function returning 0 doesn't mean the device was detected. It means,
+ * that the bus rescan was successfully started. The device will get bound to
+ * its PCI driver asynchronously.
+ */
+int pci_pwrctl_device_set_ready(struct pci_pwrctl *pwrctl)
+{
+ int ret;
+
+ if (!pwrctl->dev)
+ return -ENODEV;
+
+ pwrctl->nb.notifier_call = pci_pwrctl_notify;
+ ret = bus_register_notifier(&pci_bus_type, &pwrctl->nb);
+ if (ret)
+ return ret;
+
+ pci_lock_rescan_remove();
+ pci_rescan_bus(to_pci_dev(pwrctl->dev->parent)->bus);
+ pci_unlock_rescan_remove();
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pci_pwrctl_device_set_ready);
+
+/**
+ * pci_pwrctl_device_unset_ready() - Notify the pwrctl subsystem that the PCI
+ * device is about to be powered-down.
+ *
+ * @pwrctl: PCI power control data
+ */
+void pci_pwrctl_device_unset_ready(struct pci_pwrctl *pwrctl)
+{
+ /*
+ * We don't have to delete the link here. Typically, this function
+ * is only called when the power control device is being detached. If
+ * it is being detached then the child PCI device must have already
+ * been unbound too or the device core wouldn't let us unbind.
+ */
+ bus_unregister_notifier(&pci_bus_type, &pwrctl->nb);
+}
+EXPORT_SYMBOL_GPL(pci_pwrctl_device_unset_ready);
+
+static void devm_pci_pwrctl_device_unset_ready(void *data)
+{
+ struct pci_pwrctl *pwrctl = data;
+
+ pci_pwrctl_device_set_ready(pwrctl);
+}
+
+/**
+ * devm_pci_pwrctl_device_set_ready - Managed variant of
+ * pci_pwrctl_device_set_ready().
+ *
+ * @pwrctl: PCI power control data
+ *
+ * Returns:
+ * 0 on success, negative error number on error.
+ */
+int devm_pci_pwrctl_device_set_ready(struct device *dev,
+ struct pci_pwrctl *pwrctl)
+{
+ int ret;
+
+ ret = pci_pwrctl_device_set_ready(pwrctl);
+ if (ret)
+ return ret;
+
+ return devm_add_action_or_reset(dev,
+ devm_pci_pwrctl_device_unset_ready,
+ pwrctl);
+}
+EXPORT_SYMBOL_GPL(devm_pci_pwrctl_device_set_ready);
+
+MODULE_AUTHOR("Bartosz Golaszewski <[email protected]>");
+MODULE_DESCRIPTION("PCI Device Power Control core driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/pci-pwrctl.h b/include/linux/pci-pwrctl.h
new file mode 100644
index 000000000000..ae8324ea7eeb
--- /dev/null
+++ b/include/linux/pci-pwrctl.h
@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2024 Linaro Ltd.
+ */
+
+#ifndef __PCI_PWRCTL_H__
+#define __PCI_PWRCTL_H__
+
+#include <linux/notifier.h>
+
+struct device;
+struct device_link;
+
+/*
+ * This is a simple framework for solving the issue of PCI devices that require
+ * certain resources (regulators, GPIOs, clocks) to be enabled before the
+ * device can actually be detected on the PCI bus.
+ *
+ * The idea is to reuse the platform bus to populate OF nodes describing the
+ * PCI device and its resources, let these platform devices probe and enable
+ * relevant resources and then trigger a rescan of the PCI bus allowing for the
+ * same device (with a second associated struct device) to be registered with
+ * the PCI subsystem.
+ *
+ * To preserve a correct hierarchy for PCI power management and device reset,
+ * we create a device link between the power control platform device (parent)
+ * and the supplied PCI device (child).
+ */
+
+/**
+ * struct pci_pwrctl - PCI device power control context.
+ * @dev - Address of the power controlling device.
+ *
+ * An object of this type must be allocated by the PCI power control device and
+ * passed to the pwrctl subsystem to trigger a bus rescan and setup a device
+ * link with the device once it's up.
+ */
+struct pci_pwrctl {
+ struct device *dev;
+
+ /* Private, don't use. */
+ struct notifier_block nb;
+ struct device_link *link;
+};
+
+int pci_pwrctl_device_set_ready(struct pci_pwrctl *pwrctl);
+void pci_pwrctl_device_unset_ready(struct pci_pwrctl *pwrctl);
+int devm_pci_pwrctl_device_set_ready(struct device *dev,
+ struct pci_pwrctl *pwrctl);
+
+#endif /* __PCI_PWRCTL_H__ */
--
2.40.1
From: Bartosz Golaszewski <[email protected]>
Add a PCI compatible for the ATH11K module on QCA6390 and describe the
power inputs from the PMU that it consumes.
Signed-off-by: Bartosz Golaszewski <[email protected]>
---
.../net/wireless/qcom,ath11k-pci.yaml | 46 +++++++++++++++++++
1 file changed, 46 insertions(+)
diff --git a/Documentation/devicetree/bindings/net/wireless/qcom,ath11k-pci.yaml b/Documentation/devicetree/bindings/net/wireless/qcom,ath11k-pci.yaml
index 41d023797d7d..8675d7d0215c 100644
--- a/Documentation/devicetree/bindings/net/wireless/qcom,ath11k-pci.yaml
+++ b/Documentation/devicetree/bindings/net/wireless/qcom,ath11k-pci.yaml
@@ -17,6 +17,7 @@ description: |
properties:
compatible:
enum:
+ - pci17cb,1101 # QCA6390
- pci17cb,1103 # WCN6855
reg:
@@ -28,10 +29,55 @@ properties:
string to uniquely identify variant of the calibration data for designs
with colliding bus and device ids
+ vddrfacmn-supply:
+ description: VDD_RFA_CMN supply regulator handle
+
+ vddaon-supply:
+ description: VDD_AON supply regulator handle
+
+ vddwlcx-supply:
+ description: VDD_WL_CX supply regulator handle
+
+ vddwlmx-supply:
+ description: VDD_WL_MX supply regulator handle
+
+ vddrfa0p8-supply:
+ description: VDD_RFA_0P8 supply regulator handle
+
+ vddrfa1p2-supply:
+ description: VDD_RFA_1P2 supply regulator handle
+
+ vddrfa1p7-supply:
+ description: VDD_RFA_1P7 supply regulator handle
+
+ vddpcie0p9-supply:
+ description: VDD_PCIE_0P9 supply regulator handle
+
+ vddpcie1p8-supply:
+ description: VDD_PCIE_1P8 supply regulator handle
+
required:
- compatible
- reg
+allOf:
+ - if:
+ properties:
+ compatible:
+ contains:
+ const: pci17cb,1101
+ then:
+ required:
+ - vddrfacmn-supply
+ - vddaon-supply
+ - vddwlcx-supply
+ - vddwlmx-supply
+ - vddrfa0p8-supply
+ - vddrfa1p2-supply
+ - vddrfa1p7-supply
+ - vddpcie0p9-supply
+ - vddpcie1p8-supply
+
additionalProperties: false
examples:
--
2.40.1
On Mon, Mar 25, 2024 at 04:37:29PM +0200, Kalle Valo wrote:
> Bartosz Golaszewski <[email protected]> writes:
> > On Mon, Mar 25, 2024 at 2:57 PM Kalle Valo <[email protected]> wrote:
> >> Bartosz Golaszewski <[email protected]> writes:
> >> > From: Bartosz Golaszewski <[email protected]>
> >> >
> >> > Add a PCI compatible for the ATH11K module on QCA6390 and describe the
> >> > power inputs from the PMU that it consumes.
> >> >
> >> > Signed-off-by: Bartosz Golaszewski <[email protected]>
> >>
> >> [...]
> >>
> >> > +allOf:
> >> > + - if:
> >> > + properties:
> >> > + compatible:
> >> > + contains:
> >> > + const: pci17cb,1101
> >> > + then:
> >> > + required:
> >> > + - vddrfacmn-supply
> >> > + - vddaon-supply
> >> > + - vddwlcx-supply
> >> > + - vddwlmx-supply
> >> > + - vddrfa0p8-supply
> >> > + - vddrfa1p2-supply
> >> > + - vddrfa1p7-supply
> >> > + - vddpcie0p9-supply
> >> > + - vddpcie1p8-supply
> >>
> >> I don't know DT well enough to know what the "required:" above means,
> >> but does this take into account that there are normal "plug&play" type
> >> of QCA6390 boards as well which don't need any DT settings?
> >
> > Do they require a DT node though for some reason?
>
> You can attach the device to any PCI slot, connect the WLAN antenna and
> it just works without DT nodes. I'm trying to make sure here that basic
> setup still works.
>
> Adding also Johan and ath11k list. For example, I don't know what's the
> plan with Lenovo X13s, will it use this framework? I guess in theory we
> could have devices which use qcom,ath11k-calibration-variant from DT but
> not any of these supply properties?
In theory we could, but at least the WCN6855 in the X13s has a similar
set of supplies and enable gpios which are currently not fully described
in the devicetree as there has been no support for doing so thus far.
Instead we rely on the bootloader to enable the module.
I haven't had time to look at the latest attempt on adding support for
handling such resources, but eventually we'll need to address this in
some way.
Johan
On Tue, Mar 26, 2024 at 05:32:55PM +0100, Bartosz Golaszewski wrote:
> On Tue, Mar 26, 2024 at 4:12 PM Kalle Valo <[email protected]> wrote:
> > >> Adding also Johan and ath11k list. For example, I don't know what's the
> > >> plan with Lenovo X13s, will it use this framework? I guess in theory we
> > >> could have devices which use qcom,ath11k-calibration-variant from DT but
> > >> not any of these supply properties?
> > >
> > > Good point. I will receive the X13s in a month from now. I do plan on
> > > upstreaming correct support for WLAN and BT for it as well.
> > >
> > > I guess we can always relax the requirements once a valid use-case appears?
> >
> > I think we have such cases already now:
> >
> > $ git grep ath11k-calibration-variant -- arch
> > arch/arm64/boot/dts/qcom/qcm6490-fairphone-fp5.dts: qcom,ath11k-calibration-variant = "Fairphone_5";
> > arch/arm64/boot/dts/qcom/sc8280xp-lenovo-thinkpad-x13s.dts: qcom,ath11k-calibration-variant = "LE_X13S";
> >
> > But please do check that. I'm no DT expert :)
>
> You're thinking about making the required: field depend on the value
> of qcom,ath11k-calibration-variant? Am I getting this right?
No, I think Kalle is worried about requiring the supply properties for
certain PCI device ids, in case we have existing or future devicetrees
with those ids that did not specify them or that need not specify them
(e.g. any PC modules).
Currently we only have the X13s controller in mainline being described
by a PCIe endpoint node in DT, but it has a different id ("pci17cb,1103"
instead of "pci17cb,1101" which you are adding here).
The Fairphone controller is apparently not a PCI device at all.
Johan
On Mon, Mar 25, 2024 at 02:16:20PM +0100, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <[email protected]>
>
> Some PCI devices must be powered-on before they can be detected on the
> bus. Introduce a simple framework reusing the existing PCI OF
> infrastructure.
>
> The way this works is: a DT node representing a PCI device connected to
> the port can be matched against its power control platform driver. If
> the match succeeds, the driver is responsible for powering-up the device
> and calling pcie_pwrctl_device_set_ready() which will trigger a PCI bus
> rescan as well as subscribe to PCI bus notifications.
>
> When the device is detected and created, we'll make it consume the same
> DT node that the platform device did. When the device is bound, we'll
> create a device link between it and the parent power control device.
>
> Signed-off-by: Bartosz Golaszewski <[email protected]>
Hi Bartosz,
some minor Kernel doc nits from my side.
...
> diff --git a/drivers/pci/pwrctl/core.c b/drivers/pci/pwrctl/core.c
...
> +/**
> + * devm_pci_pwrctl_device_set_ready - Managed variant of
> + * pci_pwrctl_device_set_ready().
> + *
nit: @dev should be documented here
> + * @pwrctl: PCI power control data
> + *
> + * Returns:
> + * 0 on success, negative error number on error.
> + */
> +int devm_pci_pwrctl_device_set_ready(struct device *dev,
> + struct pci_pwrctl *pwrctl)
> +{
> + int ret;
> +
> + ret = pci_pwrctl_device_set_ready(pwrctl);
> + if (ret)
> + return ret;
> +
> + return devm_add_action_or_reset(dev,
> + devm_pci_pwrctl_device_unset_ready,
> + pwrctl);
> +}
> +EXPORT_SYMBOL_GPL(devm_pci_pwrctl_device_set_ready);
> +
> +MODULE_AUTHOR("Bartosz Golaszewski <[email protected]>");
> +MODULE_DESCRIPTION("PCI Device Power Control core driver");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/pci-pwrctl.h b/include/linux/pci-pwrctl.h
> new file mode 100644
> index 000000000000..ae8324ea7eeb
> --- /dev/null
> +++ b/include/linux/pci-pwrctl.h
> @@ -0,0 +1,51 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright (C) 2024 Linaro Ltd.
> + */
> +
> +#ifndef __PCI_PWRCTL_H__
> +#define __PCI_PWRCTL_H__
> +
> +#include <linux/notifier.h>
> +
> +struct device;
> +struct device_link;
> +
> +/*
> + * This is a simple framework for solving the issue of PCI devices that require
> + * certain resources (regulators, GPIOs, clocks) to be enabled before the
> + * device can actually be detected on the PCI bus.
> + *
> + * The idea is to reuse the platform bus to populate OF nodes describing the
> + * PCI device and its resources, let these platform devices probe and enable
> + * relevant resources and then trigger a rescan of the PCI bus allowing for the
> + * same device (with a second associated struct device) to be registered with
> + * the PCI subsystem.
> + *
> + * To preserve a correct hierarchy for PCI power management and device reset,
> + * we create a device link between the power control platform device (parent)
> + * and the supplied PCI device (child).
> + */
> +
> +/**
> + * struct pci_pwrctl - PCI device power control context.
> + * @dev - Address of the power controlling device.
nit: I think this should be "@dev: " rather than "@dev - "
As is, "./scripts/kernel-doc -none" complains.
> + *
> + * An object of this type must be allocated by the PCI power control device and
> + * passed to the pwrctl subsystem to trigger a bus rescan and setup a device
> + * link with the device once it's up.
> + */
> +struct pci_pwrctl {
> + struct device *dev;
> +
> + /* Private, don't use. */
I think Private needs to be followed by a ':' rather than a ',' to keep
kernel-doc happy.
> + struct notifier_block nb;
> + struct device_link *link;
> +};
> +
> +int pci_pwrctl_device_set_ready(struct pci_pwrctl *pwrctl);
> +void pci_pwrctl_device_unset_ready(struct pci_pwrctl *pwrctl);
> +int devm_pci_pwrctl_device_set_ready(struct device *dev,
> + struct pci_pwrctl *pwrctl);
> +
> +#endif /* __PCI_PWRCTL_H__ */
> --
> 2.40.1
>
>
On 25/03/2024 14:16, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <[email protected]>
>
> Add device-tree bindings for the ATH12K module found in the WCN7850
> package.
>
> Signed-off-by: Bartosz Golaszewski <[email protected]>
> ---
> .../bindings/net/wireless/qcom,ath12k.yaml | 100 ++++++++++++++++++
> 1 file changed, 100 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/net/wireless/qcom,ath12k.yaml
>
Reviewed-by: Krzysztof Kozlowski <[email protected]>
Best regards,
Krzysztof
On Mon, Mar 25, 2024 at 3:01 PM Kalle Valo <[email protected]> wrote:
>
> Bartosz Golaszewski <[email protected]> writes:
>
> > From: Bartosz Golaszewski <[email protected]>
> >
> > +
> > +maintainers:
> > + - Bartosz Golaszewski <[email protected]>
>
> IMHO it would be better to have just driver maintainers listed here.
>
Why? What's wrong with having the author of the bindings in the Cc list?
> > +required:
> > + - compatible
> > + - reg
> > + - vddaon-supply
> > + - vddwlcx-supply
> > + - vddwlmx-supply
> > + - vddrfacmn-supply
> > + - vddrfa0p8-supply
> > + - vddrfa1p2-supply
> > + - vddrfa1p8-supply
> > + - vddpcie0p9-supply
> > + - vddpcie1p8-supply
>
> Same comment here as in patch 4. There are also ath12k PCI devices which
> don't need DT at all. I don't know if that should be reflected in the
> bindings doc but I want to point out this.
>
But DT bindings don't apply to devices that don't have DT nodes. This
isn't an issue at all.
Bart
Bartosz Golaszewski <[email protected]> writes:
> On Mon, Mar 25, 2024 at 3:01 PM Kalle Valo <[email protected]> wrote:
>>
>> Bartosz Golaszewski <[email protected]> writes:
>>
>> > From: Bartosz Golaszewski <[email protected]>
>> >
>> > +
>> > +maintainers:
>> > + - Bartosz Golaszewski <[email protected]>
>>
>> IMHO it would be better to have just driver maintainers listed here.
>>
>
> Why? What's wrong with having the author of the bindings in the Cc list?
If you want follow the ath12k development and review patches then you
can join the ath12k list. I'm not fond of having too many maintainers,
it's not really helping anything and just extra work to periodically
cleanup the silent maintainers.
I would ask the opposite question: why add you as the maintainer?
There's not even a single ath12k patch from you, nor I haven't seen you
doing any patch review or otherwise helping others related to ath12k.
Don't get me wrong, I value the work you do with this important powerseq
feature and hopefully we get it into the tree soon. But I don't see
adding you as a maintainer at this point.
--
https://patchwork.kernel.org/project/linux-wireless/list/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
On 05/04/2024 11:33, Kalle Valo wrote:
> Bartosz Golaszewski <[email protected]> writes:
>
>> On Mon, Mar 25, 2024 at 3:01 PM Kalle Valo <[email protected]> wrote:
>>>
>>> Bartosz Golaszewski <[email protected]> writes:
>>>
>>>> From: Bartosz Golaszewski <[email protected]>
>>>>
>>>> +
>>>> +maintainers:
>>>> + - Bartosz Golaszewski <[email protected]>
>>>
>>> IMHO it would be better to have just driver maintainers listed here.
>>>
>>
>> Why? What's wrong with having the author of the bindings in the Cc list?
>
> If you want follow the ath12k development and review patches then you
> can join the ath12k list. I'm not fond of having too many maintainers,
> it's not really helping anything and just extra work to periodically
> cleanup the silent maintainers.
>
> I would ask the opposite question: why add you as the maintainer?
> There's not even a single ath12k patch from you, nor I haven't seen you
> doing any patch review or otherwise helping others related to ath12k.
> Don't get me wrong, I value the work you do with this important powerseq
> feature and hopefully we get it into the tree soon. But I don't see
> adding you as a maintainer at this point.
This is not a maintainer of driver. This is maintainer of bindings, so
someone who has hardware, datasheets, knowledge and/or interest in
keeping the bindings accurate.
All your arguments above suggest you talk about the driver. This is not
the point here.
Best regards,
Krzysztof
On 05/04/2024 11:37, Krzysztof Kozlowski wrote:
> On 05/04/2024 11:33, Kalle Valo wrote:
>> Bartosz Golaszewski <[email protected]> writes:
>>
>>> On Mon, Mar 25, 2024 at 3:01 PM Kalle Valo <[email protected]> wrote:
>>>>
>>>> Bartosz Golaszewski <[email protected]> writes:
>>>>
>>>>> From: Bartosz Golaszewski <[email protected]>
>>>>>
>>>>> +
>>>>> +maintainers:
>>>>> + - Bartosz Golaszewski <[email protected]>
>>>>
>>>> IMHO it would be better to have just driver maintainers listed here.
>>>>
>>>
>>> Why? What's wrong with having the author of the bindings in the Cc list?
>>
>> If you want follow the ath12k development and review patches then you
>> can join the ath12k list. I'm not fond of having too many maintainers,
>> it's not really helping anything and just extra work to periodically
>> cleanup the silent maintainers.
>>
>> I would ask the opposite question: why add you as the maintainer?
>> There's not even a single ath12k patch from you, nor I haven't seen you
>> doing any patch review or otherwise helping others related to ath12k.
>> Don't get me wrong, I value the work you do with this important powerseq
>> feature and hopefully we get it into the tree soon. But I don't see
>> adding you as a maintainer at this point.
>
> This is not a maintainer of driver. This is maintainer of bindings, so
> someone who has hardware, datasheets, knowledge and/or interest in
> keeping the bindings accurate.
>
> All your arguments above suggest you talk about the driver. This is not
> the point here.
>
And to clarify: I do not have opinion whether Bartosz is a suitable
person here and whether driver maintainers should be instead or not. I
only want to clarify the purpose of the binding maintainer.
Best regards,
Krzysztof
On Fri, Apr 5, 2024 at 11:34 AM Kalle Valo <[email protected]> wrote:
>
> Bartosz Golaszewski <[email protected]> writes:
>
> > On Mon, Mar 25, 2024 at 3:01 PM Kalle Valo <[email protected]> wrote:
> >>
> >> Bartosz Golaszewski <[email protected]> writes:
> >>
> >> > From: Bartosz Golaszewski <[email protected]>
> >> >
> >> > +
> >> > +maintainers:
> >> > + - Bartosz Golaszewski <[email protected]>
> >>
> >> IMHO it would be better to have just driver maintainers listed here.
> >>
> >
> > Why? What's wrong with having the author of the bindings in the Cc list?
>
> If you want follow the ath12k development and review patches then you
> can join the ath12k list. I'm not fond of having too many maintainers,
> it's not really helping anything and just extra work to periodically
> cleanup the silent maintainers.
>
> I would ask the opposite question: why add you as the maintainer?
> There's not even a single ath12k patch from you, nor I haven't seen you
> doing any patch review or otherwise helping others related to ath12k.
> Don't get me wrong, I value the work you do with this important powerseq
> feature and hopefully we get it into the tree soon. But I don't see
> adding you as a maintainer at this point.
>
In addition to what Krzysztof already said about you seamingly
confusing the maintenance of the driver vs maintenance of the
device-tree bindings (IOW: structured hardware description) and in
response to your question: I don't see any functional change to any
dt-bindings neither from you nor from Jeff. Are you convinced you can
maintain and properly review any changes?
If so, I don't really care, I can drop myself and have less work.
Bartosz
> --
> https://patchwork.kernel.org/project/linux-wireless/list/
>
> https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
On 4/5/2024 2:52 AM, Bartosz Golaszewski wrote:
> In addition to what Krzysztof already said about you seamingly
> confusing the maintenance of the driver vs maintenance of the
> device-tree bindings (IOW: structured hardware description) and in
> response to your question: I don't see any functional change to any
> dt-bindings neither from you nor from Jeff. Are you convinced you can
> maintain and properly review any changes?
Speaking just for myself, I know Bartosz is far more capable in this regard
than I am, so I'd expect him to be listed as a maintainer before me.
/jeff
On 2024/3/25 21:16, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski<[email protected]>
>
> Note: I dropped most of the the review and test tags on purpose, the code
> changed significantly and warrants a new round of reviews and tests.
>
> ===
>
> Problem statement #1: Dynamic bus chicken-and-egg problem.
>
> Certain on-board PCI devices need to be powered up before they are can be
> detected but their PCI drivers won't get bound until the device is
> powered-up so enabling the relevant resources in the PCI device driver
> itself is impossible.
>
> Problem statement #2: Sharing inter-dependent resources between devices.
>
> Certain devices that use separate drivers (often on different busses)
> share resources (regulators, clocks, etc.). Typically these resources
> are reference-counted but in some cases there are additional interactions
> between them to consider, for example specific power-up sequence timings.
>
> ===
>
> The reason for tackling both of these problems in a single series is the
> fact the the platform I'm working on - Qualcomm RB5 - deals with both and
> both need to be addressed in order to enable WLAN and Bluetooth support
> upstream.
>
> The on-board WLAN/BT package - QCA6391 - has a Power Management Unit that
> takes inputs from the host and exposes LDO outputs consumed by the BT and
> WLAN modules which can be powered-up and down independently. However
> a delay of 100ms must be respected between enabling the BT- and
> WLAN-enable GPIOs.
>
> A similar design with a discreet PMU is also employed in other models of
> the WCN family of chips although we can often do without the delays. With
> this series we add support for the WCN7850 as well.
>
> ===
>
> We introduce a new subsystem here - the power sequencing framework. The
> qcom-wcn driver that we add is its first user. It implements the power-up
> sequences for QCA6390 and WCN7850 chips. However - we only use it to
> power-up the bluetooth module in the former. We use it to driver the WLAN
> modules in both. The reason for this is that for WCN7850 we have
> comprehensive bindings already upstream together with existing DT users.
> Porting them to using the pwrseq subsystem can be done separately and in
> an incremental manner once the subsystem itself is upstream. We will also
> have to ensure backward DT compatibility. To avoid overcomplicating this
> series, let's leave it out for now.
>
> ===
>
> This series is logically split into several sections. I'll go
> patch-by-patch and explain each step.
>
> Patches 1/16-5/16:
>
> These contain all relevant DT bindings changes. We add new documents for
> the QCA6390 & WCN7850 PMUs and ATH12K devices as well as extend the bindings
> for the Qualcomm Bluetooth and ATH11K modules with regulators used by them
> in QCA6390.
>
> Patches 6/16-8/16:
>
> These contain changes to device-tree sources for the three platforms we
> work with in this series. We model the PMUs of the WLAN/BT chips as
> top-level platform devices on the device tree. In order to limit the scope
> of this series and not introduce an excessive amount of confusion with
> deprecating DT bindings, we leave the Bluetooth nodes on sm8650 and sm8550
> as is (meaning: they continue to consumer the GPIOs and power inputs from
> the host). As the WCN7850 module doesn't require any specific timings, we can
> incrementally change that later.
>
> In both cases we add WLAN nodes that consume the power outputs of the PMU.
> For QCA6390 we also make the Bluetooth node of the RB5 consume the outputs
> of the PMU - we can do it as the bindings for this chip did not define any
> supply handles prior to this series meaning we are able to get this correct
> right away.
>
> Patches 9/16-12/16:
>
> These contain the bulk of the PCI changes for this series. We introduce
> a simple framework for powering up PCI devices before detecting them on
> the bus.
>
> The general approach is as follows: PCI devices that need special
> treatment before they can be powered up, scanned and bound to their PCI
> drivers must be described on the device-tree as child nodes of the PCI
> port node. These devices will be instantiated on the platform bus. They
> will in fact be generic platform devices with the compatible of the form
> used for PCI devices already upstream ("pci<vendor ID>,<device ID">). We
> add a new directory under drivers/pci/pwrctl/ that contains PCI pwrctl
> drivers. These drivers are platform drivers that will now be matched
> against the devices instantiated from port children just like any other
> platform pairs.
>
> Both the power control platform device *AND* the associated PCI device
> reuse the same OF node and have access to the same properties. The goal
> of the platform driver is to request and bring up any required resources
> and let the pwrctl framework know that it's now OK to rescan the bus and
> detect the devices. When the device is bound, we are notified about it
> by the PCI bus notifier event and can establish a device link between the
> power control device and the PCI device so that any future extension for
> power-management will already be able to work with the correct hierachy.
>
> The reusing of the OF node is the reason for the small changes to the PCI
> OF core: as the bootloader can possibly leave the relevant regulators on
> before booting linux, the PCI device can be detected before its platform
> abstraction is probed. In this case, we find that device first and mark
> its OF node as reused. The pwrctl framework handles the opposite case
> (when the PCI device is detected only after the platform driver
> successfully enabled it).
>
> Patch 13/16 - 14/16:
>
> These add a relatively simple power sequencing subsystem and the first
> driver using it: the pwrseq module for the PMUs on the WCN family of chips.
>
> I'm proposing to add a subsystem that allows different devices to use a shared
> power sequence split into consumer-specific as well as common "units".
>
> A power sequence provider driver registers a set of units with pwrseq
> core. Each unit can be enabled and disabled and contains an optional list
> of other units which must be enabled before it itself can be. A unit
> represents a discreet chunk of the power sequence.
>
> It also registers a list of targets: a target is an abstraction wrapping
> a unit which allows consumers to tell pwrseq which unit they want to
> reach. Real-life example is the driver we're adding here: there's a set
> of common regulators, two PCIe-specific ones and two enable GPIOs: one
> for Bluetooth and one for WLAN.
>
> The Bluetooth driver requests a descriptor to the power sequencer and
> names the target it wants to reach:
>
> pwrseq = devm_pwrseq_get(dev, "bluetooth");
>
> The pwrseq core then knows that when the driver calls:
>
> pwrseq_power_on(pwrseq);
>
> It must enable the "bluetooth-enable" unit but it depends on the
> "regulators-common" unit so this one is enabled first. The provider
> driver is also in charge of assuring an appropriate delay between
> enabling the BT and WLAN enable GPIOs. The WLAN-specific resources are
> handled by the "wlan-enable" unit and so are not enabled until the WLAN
> driver requests the "wlan" target to be powered on.
>
> Another thing worth discussing is the way we associate the consumer with
> the relevant power sequencer. DT maintainers have expressed a discontent
> with the existing mmc pwrseq bindings and have NAKed an earlier
> initiative to introduce global pwrseq bindings to the kernel[1].
>
> In this approach, we model the existing regulators and GPIOs in DT but
> the pwrseq subsystem requires each provider to provide a .match()
> callback. Whenever a consumer requests a power sequencer handle, we
> iterate over the list of pwrseq drivers and call .match() for each. It's
> up to the driver to verify in a platform-specific way whether it deals
> with its consumer and let the core pwrseq code know.
>
> The advantage of this over reusing the regulator or reset subsystem is
> that it's more generalized and can handle resources of all kinds as well
> as deal with any kind of power-on sequences: for instance, Qualcomm has
> a PCI switch they want a driver for but this switch requires enabling
> some resources first (PCI pwrctl) and then configuring the device over
> I2C (which can be handled by the pwrseq provider).
>
> Patch 15:
>
> This patch makes the Qualcomm Bluetooth driver get and use the power
> sequencer for QCA6390.
>
> Patch 16:
>
> While tiny, this patch is possibly the highlight of the entire series.
> It uses the two abstraction layers we introduced before to create an
> elegant power sequencing PCI power control driver and supports the ath11k
> module on QCA6390 and ath12k on WCN7850.
>
> With this series we can now enable BT and WLAN on several new Qualcomm
> boards upstream.
>
> Tested on RB5, sm8650-qrd and sm8550-qrd.
>
> Changelog:
>
> Since v5:
> - unify the approach to modelling the WCN WLAN/BT chips by always exposing
> the PMU node on the device tree and making the WLAN and BT nodes become
> consumers of its power outputs; this includes a major rework of the DT
> sources, bindings and driver code; there's no more a separate PCI
> pwrctl driver for WCN7850, instead its power-up sequence was moved
> into the pwrseq driver common for all WCN chips
> - don't set load_uA from new regulator consumers
> - fix reported kerneldoc issues
> - drop voltage ranges for PMU outputs from DT
> - many minor tweaks and reworks
>
> v1: Original RFC:
>
> https://lore.kernel.org/lkml/[email protected]/T/
>
> v2: First real patch series (should have been PATCH v2) adding what I
> referred to back then as PCI power sequencing:
>
> https://lore.kernel.org/linux-arm-kernel/2024021413-grumbling-unlivable-c145@gregkh/T/
>
> v3: RFC for the DT representation of the PMU supplying the WLAN and BT
> modules inside the QCA6391 package (was largely separate from the
> series but probably should have been called PATCH or RFC v3):
>
> https://lore.kernel.org/all/CAMRc=Mc+GNoi57eTQg71DXkQKjdaoAmCpB=h2ndEpGnmdhVV-Q@mail.gmail.com/T/
>
> v4: Second attempt at the full series with changed scope (introduction of
> the pwrseq subsystem, should have been RFC v4)
>
> https://lore.kernel.org/lkml/[email protected]/T/
>
> v5: Two different ways of handling QCA6390 and WCN7850:
>
> https://lore.kernel.org/lkml/[email protected]/
>
> Bartosz Golaszewski (16):
> regulator: dt-bindings: describe the PMU module of the QCA6390 package
> regulator: dt-bindings: describe the PMU module of the WCN7850 package
> dt-bindings: net: bluetooth: qualcomm: describe regulators for QCA6390
> dt-bindings: net: wireless: qcom,ath11k: describe the ath11k on
> QCA6390
> dt-bindings: net: wireless: describe the ath12k PCI module
> arm64: dts: qcom: sm8550-qrd: add the Wifi node
> arm64: dts: qcom: sm8650-qrd: add the Wifi node
> arm64: dts: qcom: qrb5165-rb5: add the Wifi node
> PCI: hold the rescan mutex when scanning for the first time
> PCI/pwrctl: reuse the OF node for power controlled devices
> PCI/pwrctl: create platform devices for child OF nodes of the port
> node
> PCI/pwrctl: add PCI power control core code
> power: sequencing: implement the pwrseq core
> power: pwrseq: add a driver for the PMU module on the QCom WCN
> chipsets
> Bluetooth: qca: use the power sequencer for QCA6390
> PCI/pwrctl: add a PCI power control driver for power sequenced devices
>
> .../net/bluetooth/qualcomm-bluetooth.yaml | 17 +
> .../net/wireless/qcom,ath11k-pci.yaml | 46 +
> .../bindings/net/wireless/qcom,ath12k.yaml | 100 ++
> .../bindings/regulator/qcom,qca6390-pmu.yaml | 185 +++
> MAINTAINERS | 8 +
> arch/arm64/boot/dts/qcom/qrb5165-rb5.dts | 103 +-
> arch/arm64/boot/dts/qcom/sm8250.dtsi | 10 +
> arch/arm64/boot/dts/qcom/sm8550-qrd.dts | 97 ++
> arch/arm64/boot/dts/qcom/sm8550.dtsi | 10 +
> arch/arm64/boot/dts/qcom/sm8650-qrd.dts | 89 ++
> arch/arm64/boot/dts/qcom/sm8650.dtsi | 10 +
> drivers/bluetooth/hci_qca.c | 74 +-
> drivers/pci/Kconfig | 1 +
> drivers/pci/Makefile | 1 +
> drivers/pci/bus.c | 9 +-
> drivers/pci/of.c | 14 +-
> drivers/pci/probe.c | 2 +
> drivers/pci/pwrctl/Kconfig | 17 +
> drivers/pci/pwrctl/Makefile | 6 +
> drivers/pci/pwrctl/core.c | 136 +++
> drivers/pci/pwrctl/pci-pwrctl-pwrseq.c | 89 ++
> drivers/pci/remove.c | 2 +
> drivers/power/Kconfig | 1 +
> drivers/power/Makefile | 1 +
> drivers/power/sequencing/Kconfig | 28 +
> drivers/power/sequencing/Makefile | 6 +
> drivers/power/sequencing/core.c | 1065 +++++++++++++++++
> drivers/power/sequencing/pwrseq-qcom-wcn.c | 336 ++++++
> include/linux/pci-pwrctl.h | 51 +
> include/linux/pwrseq/consumer.h | 56 +
> include/linux/pwrseq/provider.h | 75 ++
> 31 files changed, 2614 insertions(+), 31 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/net/wireless/qcom,ath12k.yaml
> create mode 100644 Documentation/devicetree/bindings/regulator/qcom,qca6390-pmu.yaml
> create mode 100644 drivers/pci/pwrctl/Kconfig
> create mode 100644 drivers/pci/pwrctl/Makefile
> create mode 100644 drivers/pci/pwrctl/core.c
> create mode 100644 drivers/pci/pwrctl/pci-pwrctl-pwrseq.c
> create mode 100644 drivers/power/sequencing/Kconfig
> create mode 100644 drivers/power/sequencing/Makefile
> create mode 100644 drivers/power/sequencing/core.c
> create mode 100644 drivers/power/sequencing/pwrseq-qcom-wcn.c
> create mode 100644 include/linux/pci-pwrctl.h
> create mode 100644 include/linux/pwrseq/consumer.h
> create mode 100644 include/linux/pwrseq/provider.h
I tested the patchset on SM8550 and it does give me working WiFi. However I
seethe following warnings during boot.
[ 5.973011] mhi mhi0: Requested to power ON
[ 6.597591] mhi mhi0: Power on setup success
[ 6.597631] sysfs: cannot create duplicate filename '/devices/platform/soc@0/1c00000.pcie/pci0000:00/0000:00:00.0/resource0'
[ 6.597634] CPU: 7 PID: 154 Comm: kworker/u32:5 Tainted: G S 6.9.0-rc1-next-20240328-g955237c9980c #1
[ 6.597635] Hardware name: AYN Odin 2 (DT)
[ 6.597637] Workqueue: async async_run_entry_fn
[ 6.597645] Call trace:
[ 6.597646] dump_backtrace+0xa0/0x128
[ 6.597649] show_stack+0x20/0x38
[ 6.597650] dump_stack_lvl+0x74/0x90
[ 6.597653] dump_stack+0x18/0x28
[ 6.597654] sysfs_warn_dup+0x6c/0x90
[ 6.597658] sysfs_add_bin_file_mode_ns+0xdc/0x100
[ 6.597660] sysfs_create_bin_file+0x7c/0xb8
[ 6.597662] pci_create_attr+0xb4/0x1a8
[ 6.597665] pci_create_resource_files+0x64/0xd0
[ 6.597667] pci_create_sysfs_dev_files+0x24/0x40
[ 6.597669] pci_bus_add_device+0x54/0x138
[ 6.597670] pci_bus_add_devices+0x40/0x98
[ 6.597672] pci_host_probe+0x70/0xf0
[ 6.597673] dw_pcie_host_init+0x248/0x658
[ 6.597676] qcom_pcie_probe+0x234/0x330
[ 6.597677] platform_probe+0x70/0xd8
[ 6.597680] really_probe+0xc8/0x3a0
[ 6.597681] __driver_probe_device+0x84/0x170
[ 6.597682] driver_probe_device+0x44/0x120
[ 6.597683] __device_attach_driver+0xc4/0x168
[ 6.597684] bus_for_each_drv+0x8c/0xf0
[ 6.597686] __device_attach_async_helper+0xb4/0x118
[ 6.597687] async_run_entry_fn+0x40/0x178
[ 6.597689] process_one_work+0x16c/0x410
[ 6.597691] worker_thread+0x284/0x3a0
[ 6.597693] kthread+0x118/0x128
[ 6.597693] ret_from_fork+0x10/0x20
[ 6.597698] ------------[ cut here ]------------
[ 6.597698] proc_dir_entry '0000:00/00.0' already registered
[ 6.597710] WARNING: CPU: 7 PID: 154 at fs/proc/generic.c:375 proc_register+0x138/0x1d0
[ 6.597713] Modules linked in:
[ 6.597714] CPU: 7 PID: 154 Comm: kworker/u32:5 Tainted: G S 6.9.0-rc1-next-20240328-g955237c9980c #1
[ 6.597715] Hardware name: AYN Odin 2 (DT)
[ 6.597716] Workqueue: async async_run_entry_fn
[ 6.597718] pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
[ 6.597719] pc : proc_register+0x138/0x1d0
[ 6.597721] lr : proc_register+0x138/0x1d0
[ 6.597723] sp : ffff800081e3b9a0
[ 6.597723] x29: ffff800081e3b9a0 x28: 0000000000000000 x27: ffffddb2a28eabe0
[ 6.597725] x26: ffff3425c9ada5c0 x25: ffffddb2a2d4eef0 x24: ffff3425c9ada540
[ 6.597726] x23: 0000000000000004 x22: ffff3425c7b1822c x21: 0000000000000004
[ 6.597727] x20: ffff3425c7b18180 x19: ffff3425c9adaec8 x18: ffffffffffffffff
[ 6.597729] x17: 3040636f732f6d72 x16: 6f6674616c702f73 x15: ffff800081e3b910
[ 6.597730] x14: 0000000000000000 x13: 0a64657265747369 x12: 6765722079646165
[ 6.597731] x11: fffffffffff00000 x10: ffffddb2a27c4fb0 x9 : ffffddb29f5d7528
[ 6.597733] x8 : 00000000ffff7fff x7 : ffffddb2a27c4fb0 x6 : 80000000ffff8000
[ 6.597734] x5 : 0000000000000358 x4 : 0000000000000000 x3 : 00000000ffffffff
[ 6.597736] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff3425c5ce0000
[ 6.597737] Call trace:
[ 6.597737] proc_register+0x138/0x1d0
[ 6.597739] proc_create_data+0x48/0x78
[ 6.597741] pci_proc_attach_device+0x84/0x118
[ 6.597743] pci_bus_add_device+0x5c/0x138
[ 6.597744] pci_bus_add_devices+0x40/0x98
[ 6.597745] pci_host_probe+0x70/0xf0
[ 6.597746] dw_pcie_host_init+0x248/0x658
[ 6.597748] qcom_pcie_probe+0x234/0x330
[ 6.597749] platform_probe+0x70/0xd8
[ 6.597750] really_probe+0xc8/0x3a0
[ 6.597751] __driver_probe_device+0x84/0x170
[ 6.597752] driver_probe_device+0x44/0x120
[ 6.597753] __device_attach_driver+0xc4/0x168
[ 6.597754] bus_for_each_drv+0x8c/0xf0
[ 6.597756] __device_attach_async_helper+0xb4/0x118
[ 6.597757] async_run_entry_fn+0x40/0x178
[ 6.597759] process_one_work+0x16c/0x410
[ 6.597760] worker_thread+0x284/0x3a0
[ 6.597761] kthread+0x118/0x128
[ 6.597762] ret_from_fork+0x10/0x20
[ 6.597763] ---[ end trace 0000000000000000 ]---
This probably only occurs when the relevant drivers on compiled as built-in.
Similar behavior has been noticed before as well:
https://lore.kernel.org/lkml/[email protected]/T/#mdeeca9bc8e19458787d53738298abcfff443068a
Thanks,
Xilin