[PATCH edk2-platforms v2 11/16] Silicon/NXP: PciSegmentLib: Add support PCIe LsGen4 Controller

[Wasim Khan <wasim.khan@oss.nxp.com>]

From: Wasim Khan <wasim.khan@nxp.com>

PCIe Layerscape Gen4 controller is not ECAM compliant and have
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.

Co-authored-by: Vabhav Sharma <vabhav.sharma@nxp.com>
Co-authored-by: Wasim Khan <wasim.khan@nxp.com>
Signed-off-by: Wasim Khan <wasim.khan@nxp.com>
---

Notes:
    V2:
    - fix typo in commit message
    - Removed Signed-off and added Co-authored-by for co-author
    - Addressed review comments to:
      - Drop outer () while calulating Target
      - Use (Bus > 0) instead of (Bus)

 Silicon/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 e5251ecf0dd8..09ce620ef988 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;
+
+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 > 0) {
+    Target = (((Address >> 20) & 0xFF) << 24) |
+             (((Address >> 15) & 0x1F) << 19) |
+             (((Address >> 12) & 0x7) << 16);
+
+    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;
 }
-- 
2.7.4