/* * (C) Copyright 2000 * Sysgo Real-Time Solutions, GmbH <www.elinos.com> * Marius Groeger <mgroeger@sysgo.de> * * Code in faintly related to linux/arch/ppc/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). * * ----------------------------------------------------------------- * See file CREDITS for list of people who contributed to this * project. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA */ #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 *)(CFG_IMMR + 0x2000 + CFG_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 *)CFG_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 *)CFG_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; }