alder_lake_bios/Intel/AlderLake/ClientOneSiliconPkg/IpBlock/Vmd/AcpiTables/VmdPcieRp.asl

/**@file
  VMD remapped storage description for PCIe SSD remapped under VMD controller

 @copyright
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  confidential information of Intel Corporation and its suppliers and licensors,
  and is protected by worldwide copyright and trade secret laws and treaty
  provisions. No part of the Material may be used, copied, reproduced, modified,
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  Unless otherwise agreed by Intel in writing, you may not remove or alter
  this notice or any other notice embedded in Materials by Intel or
  Intel's suppliers or licensors in any way.

  This file contains an 'Intel Peripheral Driver' and is uniquely identified as
  "Intel Reference Module" and is licensed for Intel CPUs and chipsets under
  the terms of your license agreement with Intel or your vendor. This file may
  be modified by the user, subject to additional terms of the license agreement.

@par Specification Reference:
**/


Name(ID3C, 0) // Is device in D3Cold.

//
// Method to find whether PCIe port is part of logical volume
//
Method(VR3D) {
  Return(VD3C(_ADR))
}

//
// Method to turn ON remapped PCIe RP.
//
Method(VPON, 0, Serialized) {

  // If device was not set in D3 cold do not re-initiate.
  If(LEqual(ID3C ,0)) {
    Return()
  }

  // Turn on power to the remapped PCIe slot under VMD
  \_SB.PC00.VMD0.VDON(RSPT, RSPI)

  // Transition into Link Active
  RLA()

  //
  // Sleep for 100ms after transition to link active
  //
  Sleep(100)
  Store(0, ID3C)
}


//
// Method to turn OFF remapped PCIe RP.
//
Method(VPOF, 0, Serialized) {

  // Check if root port supports D3Cold
  // Return if there is no support
  // to avoid L2/L3 ready transition
  If(LNot(D3CV(RSPT, RSPI))) {
    Return()
  }

  // Transition into L23 Ready
  RL23()

  // Turn off power to the remapped PCIe slot
  \_SB.PC00.VMD0.VDOF(RSPT, RSPI)

  Store(1, ID3C)
}

//
// RL23 method puts link to L2 or L3 state. Used for RTD3 flows, before endpoint is powered down.
//
Method(RL23, 0, Serialized) {
  Name(DCFB, 0)
  Store(CBAR(0, RPD, RPF), DCFB)
  OperationRegion(DCFG, SystemMemory, DCFB, 0xC80)
  Field(DCFG, DWordAcc, NoLock, Preserve) {
    Offset(0xE0),    // 0xE0, SPR - Scratch Pad Register
    , 0,
    SCB0, 1,                   // Non-Sticky Scratch Pad Bit (NSCB)[0]
    Offset(R_PCH_PCIE_CFG_RPPGEN), // 0xE2, RPPGEN - Root Port Power Gating Enable
    , 2,
    L23E, 1,      // 2,   L23_Rdy Entry Request (L23ER)
  }

  Store(1, L23E)
  Sleep(16)
  Store(0, Local0)
  While(L23E) {
    If(Lgreater(Local0, 4))
    {
      Break
    }
    Sleep(16)
    Increment(Local0)
  }
  Store(1,SCB0)
}

//
// RLA method recovers link from L2 or L3 state. Used for RTD3 flows, right after endpoint is powered up and exits reset.
//
Method(RLA, 0, Serialized) {
  Name(DCFB, 0)
  Store (CBAR(0, RPD, RPF), DCFB)
  OperationRegion(DCFG, SystemMemory, DCFB, 0xC80)
  Field(DCFG, DWordAcc, NoLock, Preserve) {
    Offset(0x52), // LSTS - Link Status Register
    , 13,
    LASX, 1,      // 0, Link Active Status
    Offset(0xE0),    // 0xE0, SPR - Scratch Pad Register
    , 0,
    SCB0, 1,                   // Non-Sticky Scratch Pad Bit (NSCB)[0]
    Offset(R_PCH_PCIE_CFG_RPPGEN), // 0xE2, RPPGEN - Root Port Power Gating Enable
    , 3,
    L23R, 1,       // 3,   L23_Rdy to Detect Transition (L23R2DT)
    Offset(R_PCH_PCIE_CFG_PCIEPMECTL), // 0x420, PCIEPMECTL (PCIe PM Extension Control)
    , 30,
    DPGE, 1,       // PCIEPMECTL[30]: Disabled, Detect and L23_Rdy State PHY Lane Power Gating Enable (DLSULPPGE):
  }

  If(LNotEqual(SCB0,0x1)) {
    Return()
  }

  Store(1, L23R)
  Store(0, Local0)
  /// Wait for transition to Detect
  While(L23R) {
    If(Lgreater(Local0, 4))
    {
      Break
    }
    Sleep(16)
    Increment(Local0)
  }
  Store(0,SCB0)

  /// Once in Detect, wait up to 124 ms for Link Active (typically happens in under 70ms)
  /// Worst case per PCIe spec from Detect to Link Active is:
  /// 24ms in Detect (12+12), 72ms in Polling (24+48), 28ms in Config (24+2+2+2+2)
  Store(0, Local0)
  While(LEqual(LASX,0)) {
    If(Lgreater(Local0, 8))
    {
      Break
    }
    Sleep(16)
    Increment(Local0)
  }
}