/** @file
  Differentiated System Description Table Fields (SSDT)

  Copyright (c) 2014-2015, ARM Ltd. All rights reserved.<BR>
    SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#include "ArmPlatform.h"

/*
  See ACPI 6.1 Section 6.2.13

  There are two ways that _PRT can be used. ...

  In the first model, a PCI Link device is used to provide additional
  configuration information such as whether the interrupt is Level or
  Edge triggered, it is active High or Low, Shared or Exclusive, etc.

  In the second model, the PCI interrupts are hardwired to specific
  interrupt inputs on the interrupt controller and are not
  configurable. In this case, the Source field in _PRT does not
  reference a device, but instead contains the value zero, and the
  Source Index field contains the global system interrupt to which the
  PCI interrupt is hardwired.

  We use the first model with link indirection to set the correct
  interrupt type as PCI defaults (Level Triggered, Active Low) are not
  compatible with GICv2.
*/
#define LNK_DEVICE(Unique_Id, Link_Name, irq)							\
	Device(Link_Name) {									\
	    Name(_HID, EISAID("PNP0C0F"))							\
	    Name(_UID, Unique_Id)								\
	    Name(_PRS, ResourceTemplate() {							\
	        Interrupt(ResourceProducer, Level, ActiveHigh, Exclusive) { irq }		\
	    })											\
	    Method (_CRS, 0) { Return (_PRS) }							\
	    Method (_SRS, 1) { }								\
	    Method (_DIS) { }									\
	}

#define PRT_ENTRY(Address, Pin, Link)								  \
        Package (4) {                                                                             \
            Address,    /* uses the same format as _ADR */                                        \
            Pin,        /* The PCI pin number of the device (0-INTA, 1-INTB, 2-INTC, 3-INTD). */  \
            Link,       /* Interrupt allocated via Link device. */   	     	     	      	  \
            Zero        /* global system interrupt number (no used) */				  \
          }

/*
  See Reference [1] 6.1.1
  "High word–Device #, Low word–Function #. (for example, device 3, function 2 is
   0x00030002). To refer to all the functions on a device #, use a function number of FFFF)."
*/
#define ROOT_PRT_ENTRY(Pin, Link)   PRT_ENTRY(0x0000FFFF, Pin, Link)
                                                    // Device 0 for Bridge.


DefinitionBlock("SsdtPci.aml", "SSDT", 1, "ARMLTD", "ARM-JUNO", EFI_ACPI_ARM_OEM_REVISION) {
  Scope(_SB) {
	//
	// PCI Root Complex
	//
	LNK_DEVICE(1, LNKA, 168)
	LNK_DEVICE(2, LNKB, 169)
	LNK_DEVICE(3, LNKC, 170)
	LNK_DEVICE(4, LNKD, 171)

	Device(PCI0)
    {
  		Name(_HID, EISAID("PNP0A08")) // PCI Express Root Bridge
  		Name(_CID, EISAID("PNP0A03")) // Compatible PCI Root Bridge
  		Name(_SEG, Zero) // PCI Segment Group number
  		Name(_BBN, Zero) // PCI Base Bus Number
  		Name(_CCA, 1)    // Initially mark the PCI coherent (for JunoR1)

        // Root Complex 0
        Device (RP0) {
            Name(_ADR, 0xF0000000)    // Dev 0, Func 0
        }

		// PCI Routing Table
		Name(_PRT, Package() {
			ROOT_PRT_ENTRY(0, LNKA),   // INTA
			ROOT_PRT_ENTRY(1, LNKB),   // INTB
			ROOT_PRT_ENTRY(2, LNKC),   // INTC
			ROOT_PRT_ENTRY(3, LNKD),   // INTD
		})
        // Root complex resources
		Method (_CRS, 0, Serialized) {
			Name (RBUF, ResourceTemplate () {
				WordBusNumber ( // Bus numbers assigned to this root
					ResourceProducer,
					MinFixed, MaxFixed, PosDecode,
					0,   // AddressGranularity
					0,   // AddressMinimum - Minimum Bus Number
					255, // AddressMaximum - Maximum Bus Number
					0,   // AddressTranslation - Set to 0
					256  // RangeLength - Number of Busses
				)

				DWordMemory ( // 32-bit BAR Windows
					ResourceProducer, PosDecode,
					MinFixed, MaxFixed,
					Cacheable, ReadWrite,
					0x00000000, 							// Granularity
					0x50000000, 							// Min Base Address
					0x57FFFFFF, 							// Max Base Address
					0x00000000, 							// Translate
					0x08000000								// Length
				)

				QWordMemory ( // 64-bit BAR Windows
					ResourceProducer, PosDecode,
					MinFixed, MaxFixed,
					Cacheable, ReadWrite,
					0x00000000, 							// Granularity
					0x4000000000, 							// Min Base Address
					0x40FFFFFFFF, 							// Max Base Address
					0x00000000, 							// Translate
					0x100000000								// Length
				)

				DWordIo ( // IO window
					ResourceProducer,
					MinFixed,
					MaxFixed,
					PosDecode,
					EntireRange,
					0x00000000, 							// Granularity
					0x00000000, 							// Min Base Address
					0x007fffff, 							// Max Base Address
					0x5f800000, 							// Translate
					0x00800000,  							// Length
					,,,TypeTranslation
				)
			}) // Name(RBUF)

			Return (RBUF)
		} // Method(_CRS)

		//
		// OS Control Handoff
		//
		Name(SUPP, Zero) // PCI _OSC Support Field value
		Name(CTRL, Zero) // PCI _OSC Control Field value

		/*
	  See [1] 6.2.10, [2] 4.5
		*/
		Method(_OSC,4) {
			// Check for proper UUID
			If(LEqual(Arg0,ToUUID("33DB4D5B-1FF7-401C-9657-7441C03DD766"))) {
				// Create DWord-adressable fields from the Capabilities Buffer
				CreateDWordField(Arg3,0,CDW1)
				CreateDWordField(Arg3,4,CDW2)
				CreateDWordField(Arg3,8,CDW3)

				// Save Capabilities DWord2 & 3
				Store(CDW2,SUPP)
				Store(CDW3,CTRL)

				// Only allow native hot plug control if OS supports:
				// * ASPM
				// * Clock PM
				// * MSI/MSI-X
				If(LNotEqual(And(SUPP, 0x16), 0x16)) {
					And(CTRL,0x1E,CTRL) // Mask bit 0 (and undefined bits)
				}

				// Always allow native PME, AER (no dependencies)

				// Never allow SHPC (no SHPC controller in this system)
				And(CTRL,0x1D,CTRL)

#if 0
				If(LNot(And(CDW1,1))) {		// Query flag clear?
					// Disable GPEs for features granted native control.
					If(And(CTRL,0x01)) {	// Hot plug control granted?
						Store(0,HPCE)		// clear the hot plug SCI enable bit
						Store(1,HPCS)		// clear the hot plug SCI status bit
					}
					If(And(CTRL,0x04)) {	// PME control granted?
						Store(0,PMCE)		// clear the PME SCI enable bit
						Store(1,PMCS)		// clear the PME SCI status bit
					}
					If(And(CTRL,0x10)) {	// OS restoring PCIe cap structure?
						// Set status to not restore PCIe cap structure
						// upon resume from S3
						Store(1,S3CR)
					}
				}
#endif

				If(LNotEqual(Arg1,One)) {	// Unknown revision
					Or(CDW1,0x08,CDW1)
				}

				If(LNotEqual(CDW3,CTRL)) {	// Capabilities bits were masked
					Or(CDW1,0x10,CDW1)
				}
				// Update DWORD3 in the buffer
				Store(CTRL,CDW3)
				Return(Arg3)
			} Else {
				Or(CDW1,4,CDW1) // Unrecognized UUID
				Return(Arg3)
			}
		} // End _OSC
    } // PCI0
  }
}
