sysspeed.c

mtx603在vxworks下的bsp模板源代码

/* sysSpeed.c - Support for determining Bus and DRAM speed */

/* Copyright 1997-2002 Wind River Systems, Inc. */
/* Copyright 1997,1998,1999 Motorola, Inc., All Rights Reserved */
#include "copyright_wrs.h"

/*
modification history
--------------------
01g,09jul02,jrp  Integrated with sysASpeed.s (SPR 71148).
01f,29apr02,sbs  corrected warning related to vxHid1Get.
01e,16sep01,dat  Use of WRS_ASM macro
01d,04Nov99,srr  Adjusted multipliers to be ratios of 2 to avoid overflow.
01c,13jan98,srr  updated copyright dates to 1998.
01b,16aug97,scb  Add MPC750 (Arthur) support.
01a,09jul97,tb   created.
*/


/*
DESCRIPTION

This code is used for both normal and boot runtime support.  Since it is 
used with romInit, it cannot call out to any normal runtime support routines
such as vxHid1Get().
*/

/* includes */

#include "vxWorks.h"
#include "config.h"

/* defines */

/* typedefs */

/* globals */

LOCAL UINT sysHid1Get (void);
IMPORT UINT32 vxHid1Get (void);
#ifdef INCLUDE_I2C
IMPORT	void	mtxI2cDimmGet (UINT, UCHAR *, UINT);
#endif /* INCLUDE_I2C */


/* locals */

/* forward declarations */

#ifdef INCLUDE_I2C
UINT	sysDimmSpdGet (void);

/******************************************************************************
*
* sysDimmSpdGet - get the DRAM speed for the DIMM banks
*
* This function's purpose is to access the DIMMs via the I2C controller
* and return the slowest speed found.
*
* RETURNS: slowest dram speed
*/

UINT sysDimmSpdGet (void)
    {
    UCHAR DIMM_info[15];
    UINT dspeed;
    UINT ii;

    dspeed = 0;

    /* Check all of the DRAM Serial Presence Detect (SPD) SROMs */

    for (ii = 0; ii <= 6; ii += 2)
	{
	/* Get SPD struct */

	mtxI2cDimmGet((0xA0 + ii), &(DIMM_info[0]), 14);

	/* Does this DIMM use the slowest DRAM ? */

	if (DIMM_info[9] > dspeed)
		{
		/* Yes! update return value */

		dspeed = DIMM_info[9];
		}
	}

    return (dspeed);
    }

/******************************************************************************
*
* sysDimmRefreshRateGet - get DIMM refresh rate
*
* This function's purpose is to access the DIMMs via the I2C controller
* and return the fastest refresh rate required.
*
* RETURNS: refresh_rate: 0 = Normal refresh rate, Non-zero = Fast refresh rate.
*/

UINT sysDimmRefreshRateGet (void)
    {
    UCHAR DIMM_info[15];
    UINT refresh_rate;
    UINT ii;

    /* Default return value to normal refresh rate */

    refresh_rate = 0;
    
    /* Check all of the DRAM Serial Presence Detect (SPD) SROMs */

    for (ii = 0; ii <= 6; ii += 2)
	{
	/* Get SPD struct */

	mtxI2cDimmGet((0xA0 + ii), &(DIMM_info[0]), 14);

	/* Does this DIMM require a fast refresh rate? */

	if ((DIMM_info[12] == 1) || (DIMM_info[12] == 2))
		{
		/* Yes!  Update return value */

		refresh_rate = DIMM_info[12];
		}
	}

    return (refresh_rate);
    }

#endif /* INCLUDE_I2C */

/******************************************************************************
*
* sysHid1Get - read from HID1 register SPR1009.
*
* This routine will read the contents the HID1 (SPR1009)
*
* RETURNS: value of SPR1009
*/

LOCAL UINT sysHid1Get(void)
    {
    return vxHid1Get();
    }