cmos.c File Reference

#include <hal.h>
#include <debug.h>

Include dependency graph for cmos.c:

Go to the source code of this file.

Macros
#define	NDEBUG
#define	NVRAM_START   0x3FE2
#define	NVRAM_SIZE   0x1C
#define	NVRAM_UNUSED_REG   0x14
#define	NVRAM_UNUSED_BIT   0x80

Functions
static UCHAR	BCD_INT (_In_ UCHAR Bcd)
static UCHAR NTAPI	HalpReadNvram (_In_ UCHAR Register)
	_Requires_lock_held_ (HalpSystemHardwareLock)
UCHAR NTAPI	HalpReadCmos (_In_ UCHAR Reg)
VOID NTAPI	HalpWriteCmos (_In_ UCHAR Reg, _In_ UCHAR Value)
ULONG NTAPI	HalpGetCmosData (_In_ ULONG BusNumber, _In_ ULONG SlotNumber, _Out_writes_bytes_(Length) PVOID Buffer, _In_ ULONG Length)
ULONG NTAPI	HalpSetCmosData (_In_ ULONG BusNumber, _In_ ULONG SlotNumber, _In_reads_bytes_(Length) PVOID Buffer, _In_ ULONG Length)
INIT_FUNCTION VOID NTAPI	HalpInitializeCmos (VOID)
ARC_STATUS NTAPI	HalGetEnvironmentVariable (_In_ PCH Name, _In_ USHORT ValueLength, _Out_writes_z_(ValueLength) PCH Value)
ARC_STATUS NTAPI	HalSetEnvironmentVariable (_In_ PCH Name, _In_ PCH Value)
BOOLEAN NTAPI	HalQueryRealTimeClock (_Out_ PTIME_FIELDS Time)
BOOLEAN NTAPI	HalSetRealTimeClock (_In_ PTIME_FIELDS Time)

Variables
static ULONG_PTR	MappedNvram

Macro Definition Documentation

NDEBUG

#define NDEBUG

Definition at line 12 of file cmos.c.

NVRAM_SIZE

#define NVRAM_SIZE   0x1C

Definition at line 32 of file cmos.c.

NVRAM_START

#define NVRAM_START   0x3FE2

Definition at line 31 of file cmos.c.

NVRAM_UNUSED_BIT

#define NVRAM_UNUSED_BIT   0x80

Definition at line 34 of file cmos.c.

NVRAM_UNUSED_REG

#define NVRAM_UNUSED_REG   0x14

Definition at line 33 of file cmos.c.

Function Documentation

_Requires_lock_held_()

_Requires_lock_held_

(

HalpSystemHardwareLock

)

Definition at line 57 of file cmos.c.

{
    __outbyte(GDC1_IO_o_MODE_FLIPFLOP1, GDC1_NVRAM_UNPROTECT);
    WRITE_REGISTER_UCHAR((PUCHAR)(MappedNvram + Register), Value);
    __outbyte(GDC1_IO_o_MODE_FLIPFLOP1, GDC1_NVRAM_PROTECT);
}

BCD_INT()

static UCHAR BCD_INT ( _In_ UCHAR  Bcd )

static

Definition at line 43 of file cmos.c.

{
    return ((Bcd & 0xF0) >> 4) * 10 + (Bcd & 0x0F);
}

Referenced by HalQueryRealTimeClock().

HalGetEnvironmentVariable()

ARC_STATUS NTAPI HalGetEnvironmentVariable	(	_In_ PCH	Name,
		_In_ USHORT	ValueLength,
		_Out_writes_z_(ValueLength) PCH	Value
	)

Definition at line 187 of file cmos.c.

{
    UCHAR Val;

    /* Only variable supported on x86 */
    if (_stricmp(Name, "LastKnownGood"))
        return ENOENT;

    if (!MappedNvram)
        return ENOENT;

    HalpAcquireCmosSpinLock();

    Val = HalpReadNvram(NVRAM_UNUSED_REG) & NVRAM_UNUSED_BIT;

    HalpReleaseCmosSpinLock();

    /* Check the flag */
    if (Val)
        strncpy(Value, "FALSE", ValueLength);
    else
        strncpy(Value, "TRUE", ValueLength);

    return ESUCCESS;
}

HalpGetCmosData()

ULONG NTAPI HalpGetCmosData	(	_In_ ULONG	BusNumber,
		_In_ ULONG	SlotNumber,
		_Out_writes_bytes_(Length) PVOID	Buffer,
		_In_ ULONG	Length
	)

Definition at line 146 of file cmos.c.

{
    /* Not supported by hardware */
    return 0;
}

HalpInitializeCmos()

INIT_FUNCTION VOID NTAPI HalpInitializeCmos

(

VOID

)

Definition at line 171 of file cmos.c.

{
    PHYSICAL_ADDRESS PhysicalAddress;

    /* TODO: Detect TVRAM address */
    if (TRUE)
        PhysicalAddress.QuadPart = VRAM_NORMAL_TEXT + NVRAM_START;
    else
        PhysicalAddress.QuadPart = VRAM_HI_RESO_TEXT + NVRAM_START;
    MappedNvram = (ULONG_PTR)HalpMapPhysicalMemory64(PhysicalAddress, BYTES_TO_PAGES(NVRAM_SIZE));
}

HalpReadCmos()

UCHAR NTAPI HalpReadCmos

(

_In_ UCHAR

Reg

)

Definition at line 127 of file cmos.c.

{
    /* Not supported by hardware */
    return 0;
}

HalpReadNvram()

static UCHAR NTAPI HalpReadNvram ( _In_ UCHAR  Register )

static

Definition at line 51 of file cmos.c.

{
    return READ_REGISTER_UCHAR((PUCHAR)(MappedNvram + Register));
}

Referenced by HalGetEnvironmentVariable(), and HalSetEnvironmentVariable().

HalpSetCmosData()

ULONG NTAPI HalpSetCmosData	(	_In_ ULONG	BusNumber,
		_In_ ULONG	SlotNumber,
		_In_reads_bytes_(Length) PVOID	Buffer,
		_In_ ULONG	Length
	)

Definition at line 158 of file cmos.c.

{
    /* Not supported by hardware */
    return 0;
}

HalpWriteCmos()

VOID NTAPI HalpWriteCmos	(	_In_ UCHAR	Reg,
		_In_ UCHAR	Value
	)

Definition at line 136 of file cmos.c.

{
    /* Not supported by hardware */
    NOTHING;
}

HalQueryRealTimeClock()

BOOLEAN NTAPI HalQueryRealTimeClock

(

_Out_ PTIME_FIELDS

Time

)

Definition at line 259 of file cmos.c.

{
    UCHAR Temp;

    HalpAcquireCmosSpinLock();

    HalpRtcWriteCommand(RTC_CMD_TIME_READ);
    HalpRtcWriteCommand(RTC_CMD_REGISTER_SHIFT);
    KeStallExecutionProcessor(19);

    /* Set the time data */
    Time->Second = BCD_INT(HalpRtcReadByte());
    Time->Minute = BCD_INT(HalpRtcReadByte());
    Time->Hour = BCD_INT(HalpRtcReadByte());
    Time->Day = BCD_INT(HalpRtcReadByte());
    Temp = HalpRtcReadByte();
    Time->Weekday = Temp & 0x0F;
    Time->Month = Temp >> 4;
    Time->Year = BCD_INT(HalpRtcReadByte());
    Time->Milliseconds = 0;

    Time->Year += (Time->Year >= 80) ? 1900 : 2000;

    HalpRtcWriteCommand(RTC_CMD_REGISTER_HOLD);

    HalpReleaseCmosSpinLock();

    return TRUE;
}

HalSetEnvironmentVariable()

ARC_STATUS NTAPI HalSetEnvironmentVariable	(	_In_ PCH	Name,
		_In_ PCH	Value
	)

Definition at line 218 of file cmos.c.

{
    UCHAR Val;

    /* Only variable supported on x86 */
    if (_stricmp(Name, "LastKnownGood"))
        return ENOMEM;

    if (!MappedNvram)
        return ENOMEM;

    /* Check if this is true or false */
    if (!_stricmp(Value, "TRUE"))
    {
        HalpAcquireCmosSpinLock();

        Val = HalpReadNvram(NVRAM_UNUSED_REG) | NVRAM_UNUSED_BIT;
    }
    else if (!_stricmp(Value, "FALSE"))
    {
        HalpAcquireCmosSpinLock();

        Val = HalpReadNvram(NVRAM_UNUSED_REG) & ~NVRAM_UNUSED_BIT;
    }
    else
    {
        /* Fail */
        return ENOMEM;
    }

    HalpWriteNvram(NVRAM_UNUSED_REG, Val);

    HalpReleaseCmosSpinLock();

    return ESUCCESS;
}

HalSetRealTimeClock()

BOOLEAN NTAPI HalSetRealTimeClock

(

_In_ PTIME_FIELDS

Time

)

Definition at line 292 of file cmos.c.

{
    UCHAR i, j;
    UCHAR SysTime[6];

    HalpAcquireCmosSpinLock();

    HalpRtcWriteCommand(RTC_CMD_REGISTER_SHIFT);

    SysTime[0] = INT_BCD(Time->Second);
    SysTime[1] = INT_BCD(Time->Minute);
    SysTime[2] = INT_BCD(Time->Hour);
    SysTime[3] = INT_BCD(Time->Day);
    SysTime[4] = (Time->Month << 4) | (Time->Weekday & 0x0F);
    SysTime[5] = INT_BCD(Time->Year % 100);

    /* Write time fields to RTC */
    for (i = 0; i < 6; i++)
    {
        for (j = 0; j < 8; j++)
            HalpRtcWriteBit(SysTime[i] >> j);
    }

    HalpRtcWriteCommand(RTC_CMD_TIME_SET_COUNTER_HOLD);
    HalpRtcWriteCommand(RTC_CMD_REGISTER_HOLD);

    HalpReleaseCmosSpinLock();

    return TRUE;
}

Variable Documentation

MappedNvram

ULONG_PTR MappedNvram

static

Definition at line 36 of file cmos.c.

Referenced by _Requires_lock_held_(), HalGetEnvironmentVariable(), HalpInitializeCmos(), HalpReadNvram(), and HalSetEnvironmentVariable().