Re: [PATCH edk2-platforms 11/16] Silicon/NXP: PciSegmentLib: Add support PCIe LsGen4 Controller

["Wasim Khan (OSS)" <wasim.khan@oss.nxp.com>]

> -----Original Message-----
> From: Ard Biesheuvel <ard.biesheuvel@arm.com>
> Sent: Friday, May 22, 2020 3:08 PM
> To: Wasim Khan (OSS) <wasim.khan@oss.nxp.com>; devel@edk2.groups.io;
> Meenakshi Aggarwal <meenakshi.aggarwal@nxp.com>; Vabhav Sharma
> <vabhav.sharma@nxp.com>; Varun Sethi <V.Sethi@nxp.com>;
> leif@nuviainc.com; jon@solid-run.com
> Cc: Wasim Khan <wasim.khan@nxp.com>
> Subject: Re: [PATCH edk2-platforms 11/16] Silicon/NXP: PciSegmentLib: Add
> support PCIe LsGen4 Controller
> 
> On 5/22/20 1:02 AM, Wasim Khan wrote:
> > From: Wasim Khan <wasim.khan@nxp.com>
> >
> > PCIe Layerscape Gen4 controller is not ECAM complaint and have
> 
> compliant

OK

> 
> > different PCI config space region for bus 0 (Controller space) and
> > bus[0x1-0xff] on NXP SoCs.
> >
> > For config transactions for Bus0:
> >    - Config transaction address = PCIe controller address + offset
> >
> > For config transactions for Bus[0x1-0xff]:
> >    - PCIe IP requires target BDF to be written at bit[31:16] of PCIe
> >      outbound configuration window.
> >
> > PCIe LsGen4 controller uses paging mechanism to access registers.
> > To access PCIe CCSR registers which are above 3KB offset, page number
> > must be set in Bridge Control Register.
> >
> > Signed-off-by: Vabhav Sharma <vabhav.sharma@nxp.com>
> > Signed-off-by: Wasim Khan <wasim.khan@nxp.com>
> > ---
> >   .../NXP/Library/PciSegmentLib/PciSegmentLib.inf    |  1 +
> >   Silicon/NXP/Library/PciSegmentLib/PciSegmentLib.c  | 60
> +++++++++++++++++++++-
> >   2 files changed, 60 insertions(+), 1 deletion(-)
> >
> > diff --git a/Silicon/NXP/Library/PciSegmentLib/PciSegmentLib.inf
> > b/Silicon/NXP/Library/PciSegmentLib/PciSegmentLib.inf
> > index 936213dc8a9d..d6d7ea6e3b6b 100755
> > --- a/Silicon/NXP/Library/PciSegmentLib/PciSegmentLib.inf
> > +++ b/Silicon/NXP/Library/PciSegmentLib/PciSegmentLib.inf
> > @@ -33,3 +33,4 @@ [FixedPcd]
> >
> >   [Pcd]
> >     gNxpQoriqLsTokenSpaceGuid.PcdPciCfgShiftEnable
> > +  gNxpQoriqLsTokenSpaceGuid.PcdPciLsGen4Ctrl
> > diff --git a/Silicon/NXP/Library/PciSegmentLib/PciSegmentLib.c
> > b/Silicon/NXP/Library/PciSegmentLib/PciSegmentLib.c
> > index 552a425c6832..02a1525ef308 100755
> > --- a/Silicon/NXP/Library/PciSegmentLib/PciSegmentLib.c
> > +++ b/Silicon/NXP/Library/PciSegmentLib/PciSegmentLib.c
> > @@ -35,6 +35,58 @@ typedef enum {
> >     ASSERT (((A) & (0xffff0000f0000000ULL | (M))) == 0)
> >
> >   static BOOLEAN CfgShiftEnable;
> > +static BOOLEAN PciLsGen4Ctrl;
> > +
> 
> Another compile time constant?

We are initializing PciLsGen4Ctrl with PcdPciLsGen4Ctrl (dynamic PCD).
Based on SoC version, PcdPciLsGen4Ctrl will be set to true for LSGen4 controller (default false). 
Support to update these PCDs will come later (Actual use case will be with LX2160 SoC).

> 
> > +STATIC
> > +VOID
> > +PcieCfgSetTarget (
> > +  IN EFI_PHYSICAL_ADDRESS Dbi,
> > +  IN UINT32 Target)
> > +{
> > +    PciLsGen4Write32 ((UINTN)Dbi, PAB_AXI_AMAP_PEX_WIN_L(0), Target);
> > +    PciLsGen4Write32 ((UINTN)Dbi, PAB_AXI_AMAP_PEX_WIN_H(0), 0); }
> > +
> > +/**
> > +  Function to return PCIe Physical Address(PCIe view) or Controller
> > +  Address(CPU view) for NXP Layerscape Gen4 SoC
> > +
> > +  @param  Address Address passed from bus layer.
> > +  @param  Segment Segment number for Root Complex.
> > +  @param  Offset  Config space register offset.
> > +  @param  Bus     PCIe Bus number.
> > +
> > +  @return Return PCIe CPU or Controller address.
> > +
> > +**/
> > +STATIC
> > +UINT64
> > +PciLsGen4GetConfigBase (
> > +  IN  UINT64      Address,
> > +  IN  UINT16      Segment,
> > +  IN  UINT16      Offset,
> > +  IN  UINT8       Bus
> > +  )
> > +{
> > +  UINT32 Target;
> > +
> > +  if (Bus) {
> 
> Bus > 0
> 
> > +    Target = ((((Address >> 20) & 0xFF) << 24) |
> > +             (((Address >> 15) & 0x1F) << 19) |
> > +             (((Address >> 12) & 0x7) << 16));
> 
> Drop the outer ()
> 
> > +
> > +    PcieCfgSetTarget ((PCI_SEG0_DBI_BASE + PCI_DBI_SIZE_DIFF* Segment),
> Target);
> > +    return PCI_SEG0_MMIO_MEMBASE + Offset + PCI_BASE_DIFF * Segment;
> > +  } else {
> > +      if (Offset < INDIRECT_ADDR_BNDRY) {
> > +        PciLsGen4SetPg (PCI_SEG0_DBI_BASE + PCI_DBI_SIZE_DIFF * Segment,
> 0);
> > +        return (PCI_SEG0_DBI_BASE + PCI_DBI_SIZE_DIFF * Segment + Offset);
> > +      }
> > +      PciLsGen4SetPg (PCI_SEG0_DBI_BASE + PCI_DBI_SIZE_DIFF * Segment,
> OFFSET_TO_PAGE_IDX (Offset));
> > +      Offset = OFFSET_TO_PAGE_ADDR (Offset);
> > +      return (PCI_SEG0_DBI_BASE + PCI_DBI_SIZE_DIFF * Segment +
> > +Offset);
> > +  }
> > +}
> >
> >   STATIC
> >   UINT64
> > @@ -129,7 +181,12 @@ PciSegmentLibGetConfigBase (
> >     UINT8  Bus;
> >
> >     Bus = ((UINT32)Address >> 20) & 0xff;
> > -  return PciLsGetConfigBase (Address, Segment, Offset, Bus);
> > +
> > +  if (PciLsGen4Ctrl) {
> > +    return PciLsGen4GetConfigBase (Address, Segment, Offset, Bus);  }
> > + else {
> > +    return PciLsGetConfigBase (Address, Segment, Offset, Bus);  }
> >   }
> >
> >   /**
> > @@ -620,5 +677,6 @@ PciSegLibInit (
> >     )
> >   {
> >     CfgShiftEnable = CFG_SHIFT_ENABLE;
> > +  PciLsGen4Ctrl = PCI_LS_GEN4_CTRL;
> >     return EFI_SUCCESS;
> >   }
> >