[PATCH V2 0/7] Add power domain and MSI functionality with PCIe host generic ECAM driver

Mayank Rana quic_mrana at quicinc.com
Tue Jul 30 09:16:05 PDT 2024



On 7/29/2024 10:34 PM, Manivannan Sadhasivam wrote:
> On Mon, Jul 29, 2024 at 10:19:45AM -0700, Mayank Rana wrote:
>> Hi Bjorn / Mani
>>
>> Gentle ping for your review/feedback on this series.
>> Thank you.
>>
> 
> I was waiting for your reply for my comment [1]. Because that will have
> influence on this series.
> 
> - Mani
> 
> [1] https://lore.kernel.org/linux-pci/20240724095407.GA2347@thinkpad/
ok. Thanks for above response, and suggesting that you are ok with 
either new ECAM driver or updating PCIE qcom driver with ECAM mode as 
well utilizing DWC specific functionality. I still believe having 
separate PCIe QCOM ecam driver would be more useful and allow decoupling 
dwc host specific code base.

I am requesting above if you can review current MSI split functionality, 
and provide feedback on that.

Regards,
Mayank
> 
>> Regards,
>> Mayank
>>
>> On 7/15/2024 11:13 AM, Mayank Rana wrote:
>>> Based on previously received feedback, this patch series adds functionalities
>>> with existing PCIe host generic ECAM driver (pci-host-generic.c) to get PCIe
>>> host root complex functionality on Qualcomm SA8775P auto platform.
>>>
>>> Previously sent RFC patchset to have separate Qualcomm PCIe ECAM platform driver:
>>> https://lore.kernel.org/all/d10199df-5fb3-407b-b404-a0a4d067341f@quicinc.com/T/
>>>
>>> 1. Interface to allow requesting firmware to manage system resources and performing
>>> PCIe Link up (devicetree binding in terms of power domain and runtime PM APIs is used in driver)
>>> 2. Performing D3 cold with system suspend and D0 with system resume (usage of GenPD
>>> framework based power domain controls these operations)
>>> 3. SA8775P is using Synopsys Designware PCIe controller which supports MSI controller.
>>> This MSI functionality is used with PCIe host generic driver after splitting existing MSI
>>> functionality from pcie-designware-host.c file into pcie-designware-msi.c file.
>>>
>>> Below architecture is used on Qualcomm SA8775P auto platform to get ECAM compliant PCIe
>>> controller based functionality. Here firmware VM based PCIe driver takes care of resource
>>> management and performing PCIe link related handling (D0 and D3cold). Linux VM based PCIe
>>> host generic driver uses power domain to request firmware VM to perform these operations
>>> using SCMI interface.
>>> ----------------
>>>
>>>
>>>                                      ┌────────────────────────┐
>>>                                      │                        │
>>>     ┌──────────────────────┐         │     SHARED MEMORY      │            ┌──────────────────────────┐
>>>     │     Firmware VM      │         │                        │            │         Linux VM         │
>>>     │ ┌─────────┐          │         │                        │            │    ┌────────────────┐    │
>>>     │ │ Drivers │ ┌──────┐ │         │                        │            │    │   PCIE host    │    │
>>>     │ │ PCIE PHY◄─┤      │ │         │   ┌────────────────┐   │            │    │  generic driver│    │
>>>     │ │         │ │ SCMI │ │         │   │                │   │            │    │                │    │
>>>     │ │PCIE CTL │ │      │ ├─────────┼───►    PCIE        ◄───┼─────┐      │    └──┬──────────▲──┘    │
>>>     │ │         ├─►Server│ │         │   │    SHMEM       │   │     │      │       │          │       │
>>>     │ │Clk, Vreg│ │      │ │         │   │                │   │     │      │    ┌──▼──────────┴──┐    │
>>>     │ │GPIO,GDSC│ └─▲──┬─┘ │         │   └────────────────┘   │     └──────┼────┤PCIE SCMI Inst  │    │
>>>     │ └─────────┘   │  │   │         │                        │            │    └──▲──────────┬──┘    │
>>>     │               │  │   │         │                        │            │       │          │       │
>>>     └───────────────┼──┼───┘         │                        │            └───────┼──────────┼───────┘
>>>                     │  │             │                        │                    │          │
>>>                     │  │             └────────────────────────┘                    │          │
>>>                     │  │                                                           │          │
>>>                     │  │                                                           │          │
>>>                     │  │                                                           │          │
>>>                     │  │                                                           │IRQ       │HVC
>>>                 IRQ │  │HVC                                                        │          │
>>>                     │  │                                                           │          │
>>>                     │  │                                                           │          │
>>>                     │  │                                                           │          │
>>> ┌─────────────────┴──▼───────────────────────────────────────────────────────────┴──────────▼──────────────┐
>>> │                                                                                                          │
>>> │                                                                                                          │
>>> │                                      HYPERVISOR                                                          │
>>> │                                                                                                          │
>>> │                                                                                                          │
>>> │                                                                                                          │
>>> └──────────────────────────────────────────────────────────────────────────────────────────────────────────┘
>>>     ┌─────────────┐    ┌─────────────┐  ┌──────────┐   ┌───────────┐   ┌─────────────┐  ┌────────────┐
>>>     │             │    │             │  │          │   │           │   │  PCIE       │  │   PCIE     │
>>>     │   CLOCK     │    │   REGULATOR │  │   GPIO   │   │   GDSC    │   │  PHY        │  │ controller │
>>>     └─────────────┘    └─────────────┘  └──────────┘   └───────────┘   └─────────────┘  └────────────┘
>>> ----------
>>> Changes in V2:
>>> - Drop new PCIe Qcom ECAM driver, and use existing PCIe designware based MSI functionality
>>> - Add power domain based functionality within existing ECAM driver
>>>
>>> Tested:
>>> - Validated NVME functionality with PCIe0 and PCIe1 on SA8775P-RIDE platform
>>>
>>> Mayank Rana (7):
>>>     PCI: dwc: Move MSI related code to separate file
>>>     PCI: dwc: Add msi_ops to allow DBI based MSI register access
>>>     PCI: dwc: Add pcie-designware-msi driver kconfig option
>>>     dt-bindings: PCI: host-generic-pci: Add power-domains binding
>>>     PCI: host-generic: Add power domain based handling for PCIe controller
>>>     dt-bindings: PCI: host-generic-pci: Add snps,dw-pcie-ecam-msi binding
>>>     PCI: host-generic: Add dwc MSI based MSI functionality
>>>
>>>    .../devicetree/bindings/pci/host-generic-pci.yaml  |  64 +++
>>>    drivers/pci/controller/dwc/Kconfig                 |   8 +
>>>    drivers/pci/controller/dwc/Makefile                |   1 +
>>>    drivers/pci/controller/dwc/pci-keystone.c          |  12 +-
>>>    drivers/pci/controller/dwc/pcie-designware-host.c  | 438 ++-------------------
>>>    drivers/pci/controller/dwc/pcie-designware-msi.c   | 413 +++++++++++++++++++
>>>    drivers/pci/controller/dwc/pcie-designware-msi.h   |  63 +++
>>>    drivers/pci/controller/dwc/pcie-designware.c       |   1 +
>>>    drivers/pci/controller/dwc/pcie-designware.h       |  26 +-
>>>    drivers/pci/controller/dwc/pcie-rcar-gen4.c        |   1 +
>>>    drivers/pci/controller/dwc/pcie-tegra194.c         |   5 +-
>>>    drivers/pci/controller/pci-host-generic.c          | 127 +++++-
>>>    12 files changed, 723 insertions(+), 436 deletions(-)
>>>    create mode 100644 drivers/pci/controller/dwc/pcie-designware-msi.c
>>>    create mode 100644 drivers/pci/controller/dwc/pcie-designware-msi.h
>>>
> 



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