/** @file
Copyright (c) 2004 - 2014, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials are licensed and made available under
the terms and conditions of the BSD License that accompanies this distribution.
The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php.
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
Module Name:
Dimm.c
Abstract:
PPI for reading SPD modules on DIMMs.
--*/
//
// Header Files
//
#include "Platformearlyinit.h"
#define DIMM_SOCKETS 4 // Total number of DIMM sockets allowed on
// the platform
#define DIMM_SEGMENTS 1 // Total number of Segments Per DIMM.
#define MEMORY_CHANNELS 2 // Total number of memory channels
// populated on the system board
//
// Prototypes
//
EFI_STATUS
EFIAPI
GetDimmState (
IN EFI_PEI_SERVICES **PeiServices,
IN PEI_PLATFORM_DIMM_PPI *This,
IN UINT8 Dimm,
OUT PEI_PLATFORM_DIMM_STATE *State
);
EFI_STATUS
EFIAPI
SetDimmState (
IN EFI_PEI_SERVICES **PeiServices,
IN PEI_PLATFORM_DIMM_PPI *This,
IN UINT8 Dimm,
IN PEI_PLATFORM_DIMM_STATE *State
);
EFI_STATUS
EFIAPI
ReadSpd (
IN EFI_PEI_SERVICES **PeiServices,
IN PEI_PLATFORM_DIMM_PPI *This,
IN UINT8 Dimm,
IN UINT8 Offset,
IN UINTN Count,
IN OUT UINT8 *Buffer
);
static PEI_PLATFORM_DIMM_PPI mGchDimmPpi = {
DIMM_SOCKETS,
DIMM_SEGMENTS,
MEMORY_CHANNELS,
GetDimmState,
SetDimmState,
ReadSpd
};
static EFI_PEI_PPI_DESCRIPTOR mPpiPlatformDimm = {
(EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
&gPeiPlatformDimmPpiGuid,
&mGchDimmPpi
};
//
// Functions
//
/**
This function returns the current state of a single DIMM. Present indicates
that the DIMM slot is physically populated. Disabled indicates that the DIMM
should not be used.
@param PeiServices PEI services table pointer
@param This PPI pointer
@param Dimm DIMM to read from
@param State Pointer to a return buffer to be updated with the current state
of the DIMM
@retval EFI_SUCCESS The function completed successfully.
**/
EFI_STATUS
EFIAPI
GetDimmState (
IN EFI_PEI_SERVICES **PeiServices,
IN PEI_PLATFORM_DIMM_PPI *This,
IN UINT8 Dimm,
OUT PEI_PLATFORM_DIMM_STATE *State
)
{
EFI_STATUS Status;
UINT8 Buffer;
PEI_ASSERT (PeiServices, (Dimm < This->DimmSockets));
//
// A failure here does not necessarily mean that no DIMM is present.
// Read a single byte. All we care about is the return status.
//
Status = ReadSpd (
PeiServices,
This,
Dimm,
0,
1,
&Buffer
);
if (EFI_ERROR (Status)) {
State->Present = 0;
} else {
State->Present = 1;
}
//
// BUGBUG: Update to check platform variable when it is available
//
State->Disabled = 0;
State->Reserved = 0;
return EFI_SUCCESS;
}
/**
This function updates the state of a single DIMM.
@param PeiServices PEI services table pointer
@param This PPI pointer
@param Dimm DIMM to set state for
@param State Pointer to the state information to set.
@retval EFI_SUCCESS The function completed successfully.
@retval EFI_UNSUPPORTED The function is not supported.
**/
EFI_STATUS
EFIAPI
SetDimmState (
IN EFI_PEI_SERVICES **PeiServices,
IN PEI_PLATFORM_DIMM_PPI *This,
IN UINT8 Dimm,
IN PEI_PLATFORM_DIMM_STATE *State
)
{
return EFI_UNSUPPORTED;
}
/**
This function reads SPD information from a DIMM.
PeiServices PEI services table pointer
This PPI pointer
Dimm DIMM to read from
Offset Offset in DIMM
Count Number of bytes
Buffer Return buffer
@param EFI_SUCCESS The function completed successfully.
@param EFI_DEVICE_ERROR The DIMM being accessed reported a device error,
does not have an SPD module, or is not installed in
the system.
@retval EFI_TIMEOUT Time out trying to read the SPD module.
@retval EFI_INVALID_PARAMETER A parameter was outside the legal limits.
**/
EFI_STATUS
EFIAPI
ReadSpd (
IN EFI_PEI_SERVICES **PeiServices,
IN PEI_PLATFORM_DIMM_PPI *This,
IN UINT8 Dimm,
IN UINT8 Offset,
IN UINTN Count,
IN OUT UINT8 *Buffer
)
{
EFI_STATUS Status;
PEI_SMBUS_PPI *Smbus;
UINTN Index;
UINTN Index1;
EFI_SMBUS_DEVICE_ADDRESS SlaveAddress;
EFI_SMBUS_DEVICE_COMMAND Command;
UINTN Length;
Status = (**PeiServices).LocatePpi (
PeiServices,
&gPeiSmbusPpiGuid, // GUID
0, // INSTANCE
NULL, // EFI_PEI_PPI_DESCRIPTOR
&Smbus // PPI
);
ASSERT_PEI_ERROR (PeiServices, Status);
switch (Dimm) {
case 0:
SlaveAddress.SmbusDeviceAddress = SMBUS_ADDR_CH_A_1 >> 1;
break;
case 1:
SlaveAddress.SmbusDeviceAddress = SMBUS_ADDR_CH_A_2 >> 1;
break;
case 2:
SlaveAddress.SmbusDeviceAddress = SMBUS_ADDR_CH_B_1 >> 1;
break;
case 3:
SlaveAddress.SmbusDeviceAddress = SMBUS_ADDR_CH_B_2 >> 1;
break;
default:
return EFI_INVALID_PARAMETER;
}
Index = Count % 4;
if (Index != 0) {
//
// read the first serveral bytes to speed up following reading
//
for (Index1 = 0; Index1 < Index; Index1++) {
Length = 1;
Command = Offset + Index1;
Status = Smbus->Execute (
PeiServices,
Smbus,
SlaveAddress,
Command,
EfiSmbusReadByte,
FALSE,
&Length,
&Buffer[Index1]
);
if (EFI_ERROR(Status)) {
return Status;
}
}
}
//
// Now collect all the remaining bytes on 4 bytes block
//
for (; Index < Count; Index += 2) {
Command = Index + Offset;
Length = 2;
Status = Smbus->Execute (
PeiServices,
Smbus,
SlaveAddress,
Command,
EfiSmbusReadWord,
FALSE,
&Length,
&Buffer[Index]
);
if (EFI_ERROR(Status)) {
return Status;
}
Index += 2;
Command = Index + Offset;
Length = 2;
Status = Smbus->Execute (
PeiServices,
Smbus,
SlaveAddress,
Command,
EfiSmbusReadWord,
FALSE,
&Length,
&Buffer[Index]
);
if (EFI_ERROR(Status)) {
return Status;
}
}
return EFI_SUCCESS;
}
/**
This function initializes the PEIM. It simply installs the DIMM PPI.
@param FfsHeader Not used by this function
@param PeiServices Pointer to PEI services table
@retval EFI_SUCCESS The function completed successfully.
**/
EFI_STATUS
EFIAPI
PeimInitializeDimm (
IN EFI_PEI_SERVICES **PeiServices,
IN EFI_PEI_NOTIFY_DESCRIPTOR *NotifyDescriptor,
IN VOID *SmbusPpi
)
{
EFI_STATUS Status;
Status = (**PeiServices).InstallPpi (
PeiServices,
&mPpiPlatformDimm
);
ASSERT_PEI_ERROR (PeiServices, Status);
return EFI_SUCCESS;
}