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/*
* (C) Copyright 2000
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Marius Groeger <mgroeger@sysgo.de>
*
* Code in faintly related to linux/arch/powerpc/8xx_io:
* MPC8xx CPM I2C interface. Copyright (c) 1999 Dan Malek (dmalek@jlc.net).
*
* This file implements functions to read the MBX's Vital Product Data
* (VPD). I can't use the more general i2c code in mpc8xx/... since I need
* the VPD at a time where there is no RAM available yet. Hence the VPD is
* read into a special area in the DPRAM (see config_MBX.h::CFG_DPRAMVPD).
*
* -----------------------------------------------------------------
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#ifdef CONFIG_8xx
#include <commproc.h>
#endif
#include "vpd.h"
/* Location of receive/transmit buffer descriptors
* Allocate one transmit bd and one receive bd.
* IIC_BD_FREE points to free bd space which we'll use as tx buffer.
*/
#define IIC_BD_TX1 (BD_IIC_START + 0*sizeof(cbd_t))
#define IIC_BD_TX2 (BD_IIC_START + 1*sizeof(cbd_t))
#define IIC_BD_RX (BD_IIC_START + 2*sizeof(cbd_t))
#define IIC_BD_FREE (BD_IIC_START + 3*sizeof(cbd_t))
/* FIXME -- replace 0x2000 with offsetof */
#define VPD_P ((vpd_t *)(CONFIG_SYS_IMMR + 0x2000 + CONFIG_SYS_DPRAMVPD))
/* transmit/receive buffers */
#define IIC_RX_LENGTH 128
#define WITH_MICROCODE_PATCH
vpd_packet_t * vpd_find_packet(u_char ident)
{
vpd_packet_t *packet;
vpd_t *vpd = VPD_P;
packet = (vpd_packet_t *)&vpd->packets;
while ((packet->identifier != ident) && packet->identifier != 0xFF)
{
packet = (vpd_packet_t *)((char *)packet + packet->size + 2);
}
return packet;
}
void vpd_init(void)
{
volatile immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
volatile cpm8xx_t *cp = &(im->im_cpm);
volatile i2c8xx_t *i2c = (i2c8xx_t *)&(im->im_i2c);
volatile iic_t *iip;
#ifdef WITH_MICROCODE_PATCH
ulong reloc = 0;
#endif
iip = (iic_t *)&cp->cp_dparam[PROFF_IIC];
/*
* kludge: when running from flash, no microcode patch can be
* installed. However, the DPMEM usually contains non-zero
* garbage at the relocatable patch base location, so lets clear
* it now. This way the rest of the code can support the microcode
* patch dynamically.
*/
if ((ulong)vpd_init & 0xff000000)
iip->iic_rpbase = 0;
#ifdef WITH_MICROCODE_PATCH
/* Check for and use a microcode relocation patch. */
if ((reloc = iip->iic_rpbase))
iip = (iic_t *)&cp->cp_dpmem[iip->iic_rpbase];
#endif
/* Initialize Port B IIC pins */
cp->cp_pbpar |= 0x00000030;
cp->cp_pbdir |= 0x00000030;
cp->cp_pbodr |= 0x00000030;
i2c->i2c_i2mod = 0x04; /* filter clock */
i2c->i2c_i2add = 0x34; /* select an arbitrary (unique) address */
i2c->i2c_i2brg = 0x07; /* make clock run maximum slow */
i2c->i2c_i2cmr = 0x00; /* disable interrupts */
i2c->i2c_i2cer = 0x1f; /* clear events */
i2c->i2c_i2com = 0x01; /* configure i2c to work as master */
if (vpd_read(0xa4, (uchar*)VPD_P, VPD_EEPROM_SIZE, 0) != VPD_EEPROM_SIZE)
{
hang();
}
}
/* Read from I2C.
* This is a two step process. First, we send the "dummy" write
* to set the device offset for the read. Second, we perform
* the read operation.
*/
int vpd_read(uint iic_device, uchar *buf, int count, int offset)
{
volatile immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
volatile cpm8xx_t *cp = &(im->im_cpm);
volatile i2c8xx_t *i2c = (i2c8xx_t *)&(im->im_i2c);
volatile iic_t *iip;
volatile cbd_t *tbdf1, *tbdf2, *rbdf;
uchar *tb;
uchar event;
#ifdef WITH_MICROCODE_PATCH
ulong reloc = 0;
#endif
iip = (iic_t *)&cp->cp_dparam[PROFF_IIC];
#ifdef WITH_MICROCODE_PATCH
/* Check for and use a microcode relocation patch. */
if ((reloc = iip->iic_rpbase))
iip = (iic_t *)&cp->cp_dpmem[iip->iic_rpbase];
#endif
tbdf1 = (cbd_t *)&cp->cp_dpmem[IIC_BD_TX1];
tbdf2 = (cbd_t *)&cp->cp_dpmem[IIC_BD_TX2];
rbdf = (cbd_t *)&cp->cp_dpmem[IIC_BD_RX];
/* Send a "dummy write" operation. This is a write request with
* only the offset sent, followed by another start condition.
* This will ensure we start reading from the first location
* of the EEPROM.
*/
tb = (uchar*)&cp->cp_dpmem[IIC_BD_FREE];
tb[0] = iic_device & 0xfe; /* device address */
tb[1] = offset; /* offset */
tbdf1->cbd_bufaddr = (uint)tb;
tbdf1->cbd_datlen = 2;
tbdf1->cbd_sc = 0x8400;
tb += 2;
tb[0] = iic_device | 1; /* device address */
tbdf2->cbd_bufaddr = (uint)tb;
tbdf2->cbd_datlen = count+1;
tbdf2->cbd_sc = 0xbc00;
rbdf->cbd_bufaddr = (uint)buf;
rbdf->cbd_datlen = 0;
rbdf->cbd_sc = 0xb000;
iip->iic_tbase = IIC_BD_TX1;
iip->iic_tbptr = IIC_BD_TX1;
iip->iic_rbase = IIC_BD_RX;
iip->iic_rbptr = IIC_BD_RX;
iip->iic_rfcr = 0x15;
iip->iic_tfcr = 0x15;
iip->iic_mrblr = count;
iip->iic_rstate = 0;
iip->iic_tstate = 0;
i2c->i2c_i2cer = 0x1f; /* clear event mask */
i2c->i2c_i2mod |= 1; /* enable iic operation */
i2c->i2c_i2com |= 0x80; /* start master */
/* wait for IIC transfer */
do {
__asm__ volatile ("eieio");
event = i2c->i2c_i2cer;
} while (event == 0);
if ((event & 0x10) || (event & 0x04)) {
count = -1;
goto bailout;
}
bailout:
i2c->i2c_i2mod &= ~1; /* turn off iic operation */
i2c->i2c_i2cer = 0x1f; /* clear event mask */
return count;
}