[PATCH v2] nvme: put some AMD PCIE downstream NVME device to simple suspend/resume path

[Liang, Prike]

[AMD Official Use Only - Internal Distribution Only]

> -----Original Message-----
> From: Chaitanya Kulkarni <Chaitanya.Kulkarni at wdc.com>
>
> > try do the NVME shutdown save and restore in the BIOS and still need
> > PCIe power seting to resume from RTD3 for s2idle.
>
> s/seting/setting/ ? idk.
>
[Prike]  It's should be a typo and will correct it.
> > Signed-off-by: Prike Liang <Prike.Liang at amd.com>
> > ---
> > Changes in v2:
> >  Fix the patch format and check chip root complex DID instead of PCIe RP
> >   to avoid the storage device plugged in internal PCIe RP by USB adaptor.
> > ---
> >  drivers/nvme/host/pci.c | 19 +++++++++++++++++++
> >  1 file changed, 19 insertions(+)
> >
> > diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index
> > 6bad4d4..1952da1 100644
> > --- a/drivers/nvme/host/pci.c
> > +++ b/drivers/nvme/host/pci.c
> > @@ -42,6 +42,9 @@
> >  #define NVME_MAX_KB_SZ4096
> >  #define NVME_MAX_SEGS127
> >
> > +#define AMD_PCIE_ID_CZN 0x1630
> > +#define AMD_PCIE_ID_RN AMD_PCIE_ID_CZN
> > +
> >  static int use_threaded_interrupts;
> >  module_param(use_threaded_interrupts, int, 0);
> >
> > @@ -70,6 +73,12 @@ static unsigned int io_queue_depth = 1024;
> > module_param_cb(io_queue_depth, &io_queue_depth_ops,
> &io_queue_depth,
> > 0644);  MODULE_PARM_DESC(io_queue_depth, "set io queue depth,
> should
> > >= 2");
> >
> > +static const struct pci_device_id pcie_ids[] = {
> > +{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_PCIE_ID_RN) },
> > +{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_PCIE_ID_CZN) },
> > +{ }
> > +};
> > +
>
> why new global pci_device_id array is needed ?
>
[Prike] This pci_device_id  array contains the platform root complex DID which need shutdown the NVME in this armed platform for s2idle.

> >  static int io_queue_count_set(const char *val, const struct
> > kernel_param *kp)  {
> >  unsigned int n;
> > @@ -2832,6 +2841,7 @@ static bool nvme_acpi_storage_d3(struct pci_dev
> > *dev)  {
> >  struct acpi_device *adev;
> >  struct pci_dev *root;
> > +struct pci_dev *rdev;
> >  acpi_handle handle;
> >  acpi_status status;
> >  u8 val;
> > @@ -2845,6 +2855,15 @@ static bool nvme_acpi_storage_d3(struct
> pci_dev *dev)
> >  if (!root)
> >  return false;
> >
> > +rdev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0, 0));
> > +if (rdev && pci_match_id(pcie_ids, rdev)) {
> > +/* Detect NVME device which pluged in the Renoir PCIE root port
> > + * then force use quick suspend/resume path for handling the NVME
> > + * timeout during s2idle resume.
> > + */
>
> The comment should something like this :-
[Prike]  Thanks point out and miss check this during this quick send.
>
>               if (rdev && pci_match_id(pcie_ids, rdev)) {
>
> /*
>  * Detect NVMe device which pluged in the Renoir PCIe root
> port
>  * then force use quick suspend/resume path for handling
> the NVMe
>  * timeout during s2idle resume.
>  */return NVME_QUIRK_SIMPLE_SUSPEND;
>
>           }
> > +return NVME_QUIRK_SIMPLE_SUSPEND;
> > +}
> > +
> >  adev = ACPI_COMPANION(&root->dev);
> >  if (!adev)
> >  return false;