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[v2,0/8] PCI: Enable Power and configure the QPS615 PCIe switch

Message ID 20240803-qps615-v2-0-9560b7c71369@quicinc.com (mailing list archive)
Headers show
Series PCI: Enable Power and configure the QPS615 PCIe switch | expand

Message

Krishna Chaitanya Chundru Aug. 3, 2024, 3:22 a.m. UTC
QPS615 is the PCIe switch which has one upstream and three downstream
ports. One of the downstream ports is used as endpoint device of Ethernet
MAC. Other two downstream ports are supposed to connect to external
device. One Host can connect to QPS615 by upstream port.

QPS615 switch power is controlled by the GPIO's. After powering on
the switch will immediately participate in the link training. if the
host is also ready by that time PCIe link will established. 

The QPS615 needs to configured certain parameters like de-emphasis,
disable unused port etc before link is established.

The device tree properties are parsed per node under pci-pci bridge in the
devicetree. Each node has unique bdf value in the reg property, driver
uses this bdf to differentiate ports, as there are certain i2c writes to
select particulat port.
 
As the controller starts link training before the probe of pwrctl driver,
the PCIe link may come up before configuring the switch itself.
To avoid this introduce two functions in pci_ops to start_link() &
stop_link() which will disable the link training if the PCIe link is
not up yet.

Now PCI pwrctl device is the child of the pci-pcie bridge, if we want
to enable the suspend resume for pwrctl device there may be issues
since pci bridge will try to access some registers in the config which
may cause timeouts or Un clocked access as the power can be removed in
the suspend of pwrctl driver.

To solve this make PCIe controller as parent to the pci pwr ctrl driver
and create devlink between host bridge and pci pwrctl driver so that
pci pwrctl driver will go suspend only after all the PCIe devices went
to suspend.

Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
---
Changes in V1:
- Fix the code as per the comments given.
- Removed D3cold D0 sequence in suspend resume for now as it needs
  seperate discussion.
- change to dt approach for configuring the switch instead of request_firmware() approach
- Link to v1: https://lore.kernel.org/linux-pci/20240626-qps615-v1-4-2ade7bd91e02@quicinc.com/T/
---

---
Krishna chaitanya chundru (8):
      dt-bindings: PCI: Add binding for qps615
      dt-bindings: trivial-devices: Add qcom,qps615
      arm64: dts: qcom: qcs6490-rb3gen2: Add node for qps615
      PCI: Change the parent to correctly represent pcie hierarchy
      PCI: Add new start_link() & stop_link function ops
      PCI: dwc: Add support for new pci function op
      PCI: qcom: Add support for host_stop_link() & host_start_link()
      PCI: pwrctl: Add power control driver for qps615

 .../devicetree/bindings/pci/qcom,qps615.yaml       | 191 ++++++
 .../devicetree/bindings/trivial-devices.yaml       |   2 +
 arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts       | 121 ++++
 arch/arm64/boot/dts/qcom/sc7280.dtsi               |   2 +-
 drivers/pci/bus.c                                  |   3 +-
 drivers/pci/controller/dwc/pcie-designware-host.c  |  18 +
 drivers/pci/controller/dwc/pcie-designware.h       |  16 +
 drivers/pci/controller/dwc/pcie-qcom.c             |  39 ++
 drivers/pci/pwrctl/Kconfig                         |   7 +
 drivers/pci/pwrctl/Makefile                        |   1 +
 drivers/pci/pwrctl/core.c                          |   9 +-
 drivers/pci/pwrctl/pci-pwrctl-qps615.c             | 638 +++++++++++++++++++++
 include/linux/pci.h                                |   2 +
 13 files changed, 1046 insertions(+), 3 deletions(-)
---
base-commit: 1722389b0d863056d78287a120a1d6cadb8d4f7b
change-id: 20240727-qps615-e2894a38d36f

Best regards,

Comments

Dmitry Baryshkov Aug. 3, 2024, 10:56 a.m. UTC | #1
On Sat, Aug 03, 2024 at 08:52:46AM GMT, Krishna chaitanya chundru wrote:
> QPS615 is the PCIe switch which has one upstream and three downstream
> ports. One of the downstream ports is used as endpoint device of Ethernet
> MAC. Other two downstream ports are supposed to connect to external
> device. One Host can connect to QPS615 by upstream port.
> 
> QPS615 switch power is controlled by the GPIO's. After powering on
> the switch will immediately participate in the link training. if the
> host is also ready by that time PCIe link will established. 
> 
> The QPS615 needs to configured certain parameters like de-emphasis,
> disable unused port etc before link is established.
> 
> The device tree properties are parsed per node under pci-pci bridge in the
> devicetree. Each node has unique bdf value in the reg property, driver
> uses this bdf to differentiate ports, as there are certain i2c writes to
> select particulat port.
>  
> As the controller starts link training before the probe of pwrctl driver,
> the PCIe link may come up before configuring the switch itself.
> To avoid this introduce two functions in pci_ops to start_link() &
> stop_link() which will disable the link training if the PCIe link is
> not up yet.
> 
> Now PCI pwrctl device is the child of the pci-pcie bridge, if we want
> to enable the suspend resume for pwrctl device there may be issues
> since pci bridge will try to access some registers in the config which
> may cause timeouts or Un clocked access as the power can be removed in
> the suspend of pwrctl driver.
> 
> To solve this make PCIe controller as parent to the pci pwr ctrl driver
> and create devlink between host bridge and pci pwrctl driver so that
> pci pwrctl driver will go suspend only after all the PCIe devices went
> to suspend.
> 
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> ---
> Changes in V1:
> - Fix the code as per the comments given.

This is not a proper changelog entry. It doesn't allow reviewers to
understand what actually happened. Could you please list your actual
changes in a reply and also include them in a changelog if there is a
need for v3.

> - Removed D3cold D0 sequence in suspend resume for now as it needs
>   seperate discussion.
> - change to dt approach for configuring the switch instead of request_firmware() approach
> - Link to v1: https://lore.kernel.org/linux-pci/20240626-qps615-v1-4-2ade7bd91e02@quicinc.com/T/
> ---
>
Krzysztof Kozlowski Aug. 4, 2024, 8:57 a.m. UTC | #2
On 03/08/2024 05:22, Krishna chaitanya chundru wrote:
> QPS615 is the PCIe switch which has one upstream and three downstream
> ports. One of the downstream ports is used as endpoint device of Ethernet
> MAC. Other two downstream ports are supposed to connect to external
> device. One Host can connect to QPS615 by upstream port.
> 
> QPS615 switch power is controlled by the GPIO's. After powering on
> the switch will immediately participate in the link training. if the
> host is also ready by that time PCIe link will established. 
> 
> The QPS615 needs to configured certain parameters like de-emphasis,
> disable unused port etc before link is established.
> 
> The device tree properties are parsed per node under pci-pci bridge in the
> devicetree. Each node has unique bdf value in the reg property, driver
> uses this bdf to differentiate ports, as there are certain i2c writes to
> select particulat port.
>  
> As the controller starts link training before the probe of pwrctl driver,
> the PCIe link may come up before configuring the switch itself.
> To avoid this introduce two functions in pci_ops to start_link() &
> stop_link() which will disable the link training if the PCIe link is
> not up yet.
> 
> Now PCI pwrctl device is the child of the pci-pcie bridge, if we want
> to enable the suspend resume for pwrctl device there may be issues
> since pci bridge will try to access some registers in the config which
> may cause timeouts or Un clocked access as the power can be removed in
> the suspend of pwrctl driver.
> 
> To solve this make PCIe controller as parent to the pci pwr ctrl driver
> and create devlink between host bridge and pci pwrctl driver so that
> pci pwrctl driver will go suspend only after all the PCIe devices went
> to suspend.
> 
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> ---
> Changes in V1:
> - Fix the code as per the comments given.

You did not implement the comments so such changelog is rather a joke.
Respond to each comment from v1 and acknowledge it.

Then write detailed changelog.

Best regards,
Krzysztof
Krishna Chaitanya Chundru Aug. 5, 2024, 4:18 a.m. UTC | #3
On 8/4/2024 2:27 PM, Krzysztof Kozlowski wrote:
> On 03/08/2024 05:22, Krishna chaitanya chundru wrote:
>> QPS615 is the PCIe switch which has one upstream and three downstream
>> ports. One of the downstream ports is used as endpoint device of Ethernet
>> MAC. Other two downstream ports are supposed to connect to external
>> device. One Host can connect to QPS615 by upstream port.
>>
>> QPS615 switch power is controlled by the GPIO's. After powering on
>> the switch will immediately participate in the link training. if the
>> host is also ready by that time PCIe link will established.
>>
>> The QPS615 needs to configured certain parameters like de-emphasis,
>> disable unused port etc before link is established.
>>
>> The device tree properties are parsed per node under pci-pci bridge in the
>> devicetree. Each node has unique bdf value in the reg property, driver
>> uses this bdf to differentiate ports, as there are certain i2c writes to
>> select particulat port.
>>   
>> As the controller starts link training before the probe of pwrctl driver,
>> the PCIe link may come up before configuring the switch itself.
>> To avoid this introduce two functions in pci_ops to start_link() &
>> stop_link() which will disable the link training if the PCIe link is
>> not up yet.
>>
>> Now PCI pwrctl device is the child of the pci-pcie bridge, if we want
>> to enable the suspend resume for pwrctl device there may be issues
>> since pci bridge will try to access some registers in the config which
>> may cause timeouts or Un clocked access as the power can be removed in
>> the suspend of pwrctl driver.
>>
>> To solve this make PCIe controller as parent to the pci pwr ctrl driver
>> and create devlink between host bridge and pci pwrctl driver so that
>> pci pwrctl driver will go suspend only after all the PCIe devices went
>> to suspend.
>>
>> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>> ---
>> Changes in V1:
>> - Fix the code as per the comments given.
> 
> You did not implement the comments so such changelog is rather a joke.
> Respond to each comment from v1 and acknowledge it.
> 
> Then write detailed changelog.
> 
> Best regards,
> Krzysztof
> 
I will write a detailed changelog from v3 onwards spare me for this time.

- Krishna Chaitanya.
Krishna Chaitanya Chundru Aug. 5, 2024, 4:19 a.m. UTC | #4
On 8/3/2024 4:26 PM, Dmitry Baryshkov wrote:
> On Sat, Aug 03, 2024 at 08:52:46AM GMT, Krishna chaitanya chundru wrote:
>> QPS615 is the PCIe switch which has one upstream and three downstream
>> ports. One of the downstream ports is used as endpoint device of Ethernet
>> MAC. Other two downstream ports are supposed to connect to external
>> device. One Host can connect to QPS615 by upstream port.
>>
>> QPS615 switch power is controlled by the GPIO's. After powering on
>> the switch will immediately participate in the link training. if the
>> host is also ready by that time PCIe link will established.
>>
>> The QPS615 needs to configured certain parameters like de-emphasis,
>> disable unused port etc before link is established.
>>
>> The device tree properties are parsed per node under pci-pci bridge in the
>> devicetree. Each node has unique bdf value in the reg property, driver
>> uses this bdf to differentiate ports, as there are certain i2c writes to
>> select particulat port.
>>   
>> As the controller starts link training before the probe of pwrctl driver,
>> the PCIe link may come up before configuring the switch itself.
>> To avoid this introduce two functions in pci_ops to start_link() &
>> stop_link() which will disable the link training if the PCIe link is
>> not up yet.
>>
>> Now PCI pwrctl device is the child of the pci-pcie bridge, if we want
>> to enable the suspend resume for pwrctl device there may be issues
>> since pci bridge will try to access some registers in the config which
>> may cause timeouts or Un clocked access as the power can be removed in
>> the suspend of pwrctl driver.
>>
>> To solve this make PCIe controller as parent to the pci pwr ctrl driver
>> and create devlink between host bridge and pci pwrctl driver so that
>> pci pwrctl driver will go suspend only after all the PCIe devices went
>> to suspend.
>>
>> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>> ---
>> Changes in V1:
>> - Fix the code as per the comments given.
> 
> This is not a proper changelog entry. It doesn't allow reviewers to
> understand what actually happened. Could you please list your actual
> changes in a reply and also include them in a changelog if there is a
> need for v3.
> 
ack
- Krishna Chaitanya.
>> - Removed D3cold D0 sequence in suspend resume for now as it needs
>>    seperate discussion.
>> - change to dt approach for configuring the switch instead of request_firmware() approach
>> - Link to v1: https://lore.kernel.org/linux-pci/20240626-qps615-v1-4-2ade7bd91e02@quicinc.com/T/
>> ---
>>
>
Krishna Chaitanya Chundru Aug. 5, 2024, 4:34 a.m. UTC | #5
On 8/3/2024 8:52 AM, Krishna chaitanya chundru wrote:
> QPS615 is the PCIe switch which has one upstream and three downstream
> ports. One of the downstream ports is used as endpoint device of Ethernet
> MAC. Other two downstream ports are supposed to connect to external
> device. One Host can connect to QPS615 by upstream port.
> 
> QPS615 switch power is controlled by the GPIO's. After powering on
> the switch will immediately participate in the link training. if the
> host is also ready by that time PCIe link will established.
> 
> The QPS615 needs to configured certain parameters like de-emphasis,
> disable unused port etc before link is established.
> 
> The device tree properties are parsed per node under pci-pci bridge in the
> devicetree. Each node has unique bdf value in the reg property, driver
> uses this bdf to differentiate ports, as there are certain i2c writes to
> select particulat port.
>   
> As the controller starts link training before the probe of pwrctl driver,
> the PCIe link may come up before configuring the switch itself.
> To avoid this introduce two functions in pci_ops to start_link() &
> stop_link() which will disable the link training if the PCIe link is
> not up yet.
> 
> Now PCI pwrctl device is the child of the pci-pcie bridge, if we want
> to enable the suspend resume for pwrctl device there may be issues
> since pci bridge will try to access some registers in the config which
> may cause timeouts or Un clocked access as the power can be removed in
> the suspend of pwrctl driver.
> 
> To solve this make PCIe controller as parent to the pci pwr ctrl driver
> and create devlink between host bridge and pci pwrctl driver so that
> pci pwrctl driver will go suspend only after all the PCIe devices went
> to suspend.
> 
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> ---
> Changes in V1:
> - Fix the code as per the comments given.
changes in v1:
- Instead of referencing whole i2c-bus add i2c-client node and reference 
it (Dmitry)
- Change the regulator's as per the schematics as per offline review
(bjorn Andresson)
- Remove additional host check in bus.c (Bart)
- For stop_link op change return type from int to void (Bart)
- Remove firmware based approach for configuring sequence as suggested
by multiple reviewers.
- Introduce new dt-properties for the switch to configure the switch
as we are replacing the firmware based approach.
- The downstream ports add properties in the child nodes which will
represented in PCIe hierarchy format.
- Removed D3cold D0 sequence in suspend resume for now as it needs
separate discussion.

- Krishna Chaitanya.
> - Removed D3cold D0 sequence in suspend resume for now as it needs
>    seperate discussion.
> - change to dt approach for configuring the switch instead of request_firmware() approach
> - Link to v1: https://lore.kernel.org/linux-pci/20240626-qps615-v1-4-2ade7bd91e02@quicinc.com/T/
> ---
> 
> ---
> Krishna chaitanya chundru (8):
>        dt-bindings: PCI: Add binding for qps615
>        dt-bindings: trivial-devices: Add qcom,qps615
>        arm64: dts: qcom: qcs6490-rb3gen2: Add node for qps615
>        PCI: Change the parent to correctly represent pcie hierarchy
>        PCI: Add new start_link() & stop_link function ops
>        PCI: dwc: Add support for new pci function op
>        PCI: qcom: Add support for host_stop_link() & host_start_link()
>        PCI: pwrctl: Add power control driver for qps615
> 
>   .../devicetree/bindings/pci/qcom,qps615.yaml       | 191 ++++++
>   .../devicetree/bindings/trivial-devices.yaml       |   2 +
>   arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts       | 121 ++++
>   arch/arm64/boot/dts/qcom/sc7280.dtsi               |   2 +-
>   drivers/pci/bus.c                                  |   3 +-
>   drivers/pci/controller/dwc/pcie-designware-host.c  |  18 +
>   drivers/pci/controller/dwc/pcie-designware.h       |  16 +
>   drivers/pci/controller/dwc/pcie-qcom.c             |  39 ++
>   drivers/pci/pwrctl/Kconfig                         |   7 +
>   drivers/pci/pwrctl/Makefile                        |   1 +
>   drivers/pci/pwrctl/core.c                          |   9 +-
>   drivers/pci/pwrctl/pci-pwrctl-qps615.c             | 638 +++++++++++++++++++++
>   include/linux/pci.h                                |   2 +
>   13 files changed, 1046 insertions(+), 3 deletions(-)
> ---
> base-commit: 1722389b0d863056d78287a120a1d6cadb8d4f7b
> change-id: 20240727-qps615-e2894a38d36f
> 
> Best regards,
Rob Herring Aug. 5, 2024, 3 p.m. UTC | #6
On Sat, 03 Aug 2024 08:52:46 +0530, Krishna chaitanya chundru wrote:
> QPS615 is the PCIe switch which has one upstream and three downstream
> ports. One of the downstream ports is used as endpoint device of Ethernet
> MAC. Other two downstream ports are supposed to connect to external
> device. One Host can connect to QPS615 by upstream port.
> 
> QPS615 switch power is controlled by the GPIO's. After powering on
> the switch will immediately participate in the link training. if the
> host is also ready by that time PCIe link will established.
> 
> The QPS615 needs to configured certain parameters like de-emphasis,
> disable unused port etc before link is established.
> 
> The device tree properties are parsed per node under pci-pci bridge in the
> devicetree. Each node has unique bdf value in the reg property, driver
> uses this bdf to differentiate ports, as there are certain i2c writes to
> select particulat port.
> 
> As the controller starts link training before the probe of pwrctl driver,
> the PCIe link may come up before configuring the switch itself.
> To avoid this introduce two functions in pci_ops to start_link() &
> stop_link() which will disable the link training if the PCIe link is
> not up yet.
> 
> Now PCI pwrctl device is the child of the pci-pcie bridge, if we want
> to enable the suspend resume for pwrctl device there may be issues
> since pci bridge will try to access some registers in the config which
> may cause timeouts or Un clocked access as the power can be removed in
> the suspend of pwrctl driver.
> 
> To solve this make PCIe controller as parent to the pci pwr ctrl driver
> and create devlink between host bridge and pci pwrctl driver so that
> pci pwrctl driver will go suspend only after all the PCIe devices went
> to suspend.
> 
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> ---
> Changes in V1:
> - Fix the code as per the comments given.
> - Removed D3cold D0 sequence in suspend resume for now as it needs
>   seperate discussion.
> - change to dt approach for configuring the switch instead of request_firmware() approach
> - Link to v1: https://lore.kernel.org/linux-pci/20240626-qps615-v1-4-2ade7bd91e02@quicinc.com/T/
> ---
> 
> ---
> Krishna chaitanya chundru (8):
>       dt-bindings: PCI: Add binding for qps615
>       dt-bindings: trivial-devices: Add qcom,qps615
>       arm64: dts: qcom: qcs6490-rb3gen2: Add node for qps615
>       PCI: Change the parent to correctly represent pcie hierarchy
>       PCI: Add new start_link() & stop_link function ops
>       PCI: dwc: Add support for new pci function op
>       PCI: qcom: Add support for host_stop_link() & host_start_link()
>       PCI: pwrctl: Add power control driver for qps615
> 
>  .../devicetree/bindings/pci/qcom,qps615.yaml       | 191 ++++++
>  .../devicetree/bindings/trivial-devices.yaml       |   2 +
>  arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts       | 121 ++++
>  arch/arm64/boot/dts/qcom/sc7280.dtsi               |   2 +-
>  drivers/pci/bus.c                                  |   3 +-
>  drivers/pci/controller/dwc/pcie-designware-host.c  |  18 +
>  drivers/pci/controller/dwc/pcie-designware.h       |  16 +
>  drivers/pci/controller/dwc/pcie-qcom.c             |  39 ++
>  drivers/pci/pwrctl/Kconfig                         |   7 +
>  drivers/pci/pwrctl/Makefile                        |   1 +
>  drivers/pci/pwrctl/core.c                          |   9 +-
>  drivers/pci/pwrctl/pci-pwrctl-qps615.c             | 638 +++++++++++++++++++++
>  include/linux/pci.h                                |   2 +
>  13 files changed, 1046 insertions(+), 3 deletions(-)
> ---
> base-commit: 1722389b0d863056d78287a120a1d6cadb8d4f7b
> change-id: 20240727-qps615-e2894a38d36f
> 
> Best regards,
> --
> Krishna chaitanya chundru <quic_krichai@quicinc.com>
> 
> 
> 


My bot found new DTB warnings on the .dts files added or changed in this
series.

Some warnings may be from an existing SoC .dtsi. Or perhaps the warnings
are fixed by another series. Ultimately, it is up to the platform
maintainer whether these warnings are acceptable or not. No need to reply
unless the platform maintainer has comments.

If you already ran DT checks and didn't see these error(s), then
make sure dt-schema is up to date:

  pip3 install dtschema --upgrade


New warnings running 'make CHECK_DTBS=y qcom/qcs6490-rb3gen2.dtb' for 20240803-qps615-v2-0-9560b7c71369@quicinc.com:

arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts:746.12-753.5: Warning (pci_device_bus_num): /soc@0/pcie@1c08000/pcie@0/pcie@0,0/pcie@1,0: PCI bus number 2 out of range, expected (0 - 0)
arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts:755.12-762.5: Warning (pci_device_bus_num): /soc@0/pcie@1c08000/pcie@0/pcie@0,0/pcie@2,0: PCI bus number 2 out of range, expected (0 - 0)
arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts:764.12-786.5: Warning (pci_device_bus_num): /soc@0/pcie@1c08000/pcie@0/pcie@0,0/pcie@3,0: PCI bus number 2 out of range, expected (0 - 0)
arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts:771.13-777.6: Warning (pci_device_bus_num): /soc@0/pcie@1c08000/pcie@0/pcie@0,0/pcie@3,0/pcie@0,0: PCI bus number 5 out of range, expected (0 - 0)
arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts:779.13-785.6: Warning (pci_device_bus_num): /soc@0/pcie@1c08000/pcie@0/pcie@0,0/pcie@3,0/pcie@0,1: PCI bus number 5 out of range, expected (0 - 0)
Ilpo Järvinen Aug. 6, 2024, 3:24 p.m. UTC | #7
On Sat, 3 Aug 2024, Krishna chaitanya chundru wrote:

> QPS615 is the PCIe switch which has one upstream and three downstream
> ports. One of the downstream ports is used as endpoint device of Ethernet
> MAC. Other two downstream ports are supposed to connect to external
> device. One Host can connect to QPS615 by upstream port.
> 
> QPS615 switch power is controlled by the GPIO's. After powering on
> the switch will immediately participate in the link training. if the
> host is also ready by that time PCIe link will established. 
> 
> The QPS615 needs to configured certain parameters like de-emphasis,
> disable unused port etc before link is established.
> 
> The device tree properties are parsed per node under pci-pci bridge in the
> devicetree. Each node has unique bdf value in the reg property, driver
> uses this bdf to differentiate ports, as there are certain i2c writes to
> select particulat port.
>  
> As the controller starts link training before the probe of pwrctl driver,
> the PCIe link may come up before configuring the switch itself.
> To avoid this introduce two functions in pci_ops to start_link() &
> stop_link() which will disable the link training if the PCIe link is
> not up yet.

???

This paragraph contradicts with itself. First it says link training starts 
and the link may come up, and then it says opposite, that is, disable the 
link training if the link is not up yet. So which way it is?

If link can come up, why do you need to disable link training at all? 
Cannot you just trigger another link training after the configuration has 
been done so the new configuration is captured? If not, why?