From 79b2d0bb2eae09602448f7a7cb56530d2f31e6c6 Mon Sep 17 00:00:00 2001 From: Stefan Roese Date: Tue, 20 Feb 2007 10:27:08 +0100 Subject: [PATCH] PPC4xx: Add support for multiple I2C busses This patch adds support for multiple I2C busses on the PPC4xx platforms. Define CONFIG_I2C_MULTI_BUS in the board config file to make use of this feature. It also merges the 405 and 440 i2c header files into one common file 4xx_i2c.h. Also the 4xx i2c reset procedure is reworked since I experienced some problems with the first access on the 440SPe Katmai board. Signed-off-by: Stefan Roese --- cpu/ppc4xx/i2c.c | 458 +++++++++++++++++++++++++++++-------------------------- 1 file changed, 245 insertions(+), 213 deletions(-) (limited to 'cpu') diff --git a/cpu/ppc4xx/i2c.c b/cpu/ppc4xx/i2c.c index 7db1cd8046..0b056a15de 100644 --- a/cpu/ppc4xx/i2c.c +++ b/cpu/ppc4xx/i2c.c @@ -1,91 +1,100 @@ -/*****************************************************************************/ -/* I2C Bus interface initialisation and I2C Commands */ -/* for PPC405GP */ -/* Author : AS HARNOIS */ -/* Date : 13.Dec.00 */ -/*****************************************************************************/ +/* + * (C) Copyright 2007 + * Stefan Roese, DENX Software Engineering, sr@denx.de. + * + * based on work by Anne Sophie Harnois + * + * (C) Copyright 2001 + * Bill Hunter, Wave 7 Optics, williamhunter@mediaone.net + * + * 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 #include -#if defined(CONFIG_440) -# include <440_i2c.h> -#else -# include <405gp_i2c.h> -#endif +#include <4xx_i2c.h> #include +#include #ifdef CONFIG_HARD_I2C DECLARE_GLOBAL_DATA_PTR; -#define IIC_OK 0 -#define IIC_NOK 1 -#define IIC_NOK_LA 2 /* Lost arbitration */ -#define IIC_NOK_ICT 3 /* Incomplete transfer */ -#define IIC_NOK_XFRA 4 /* Transfer aborted */ -#define IIC_NOK_DATA 5 /* No data in buffer */ -#define IIC_NOK_TOUT 6 /* Transfer timeout */ - -#define IIC_TIMEOUT 1 /* 1 seconde */ - +#if defined(CONFIG_I2C_MULTI_BUS) +/* Initialize the bus pointer to whatever one the SPD EEPROM is on. + * Default is bus 0. This is necessary because the DDR initialization + * runs from ROM, and we can't switch buses because we can't modify + * the global variables. + */ +#ifdef CFG_SPD_BUS_NUM +static unsigned int i2c_bus_num __attribute__ ((section ("data"))) = CFG_SPD_BUS_NUM; +#else +static unsigned int i2c_bus_num __attribute__ ((section ("data"))) = 0; +#endif +#endif /* CONFIG_I2C_MULTI_BUS */ -static void _i2c_bus_reset (void) +static void _i2c_bus_reset(void) { - int i, status; + int i; + u8 dc; /* Reset status register */ /* write 1 in SCMP and IRQA to clear these fields */ - out8 (IIC_STS, 0x0A); + out_8((u8 *)IIC_STS, 0x0A); /* write 1 in IRQP IRQD LA ICT XFRA to clear these fields */ - out8 (IIC_EXTSTS, 0x8F); - __asm__ volatile ("eieio"); - - /* - * Get current state, reset bus - * only if no transfers are pending. - */ - i = 10; - do { - /* Get status */ - status = in8 (IIC_STS); - udelay (500); /* 500us */ - i--; - } while ((status & IIC_STS_PT) && (i > 0)); - /* Soft reset controller */ - status = in8 (IIC_XTCNTLSS); - out8 (IIC_XTCNTLSS, (status | IIC_XTCNTLSS_SRST)); - __asm__ volatile ("eieio"); - - /* make sure where in initial state, data hi, clock hi */ - out8 (IIC_DIRECTCNTL, 0xC); - for (i = 0; i < 10; i++) { - if ((in8 (IIC_DIRECTCNTL) & 0x3) != 0x3) { - /* clock until we get to known state */ - out8 (IIC_DIRECTCNTL, 0x8); /* clock lo */ - udelay (100); /* 100us */ - out8 (IIC_DIRECTCNTL, 0xC); /* clock hi */ - udelay (100); /* 100us */ - } else { - break; + out_8((u8 *)IIC_EXTSTS, 0x8F); + + /* Place chip in the reset state */ + out_8((u8 *)IIC_XTCNTLSS, IIC_XTCNTLSS_SRST); + + /* Check if bus is free */ + dc = in_8((u8 *)IIC_DIRECTCNTL); + if (!DIRCTNL_FREE(dc)){ + /* Try to set bus free state */ + out_8((u8 *)IIC_DIRECTCNTL, IIC_DIRCNTL_SDAC | IIC_DIRCNTL_SCC); + + /* Wait until we regain bus control */ + for (i = 0; i < 100; ++i) { + dc = in_8((u8 *)IIC_DIRECTCNTL); + if (DIRCTNL_FREE(dc)) + break; + + /* Toggle SCL line */ + dc ^= IIC_DIRCNTL_SCC; + out_8((u8 *)IIC_DIRECTCNTL, dc); + udelay(10); + dc ^= IIC_DIRCNTL_SCC; + out_8((u8 *)IIC_DIRECTCNTL, dc); } } - /* send start condition */ - out8 (IIC_DIRECTCNTL, 0x4); - udelay (1000); /* 1ms */ - /* send stop condition */ - out8 (IIC_DIRECTCNTL, 0xC); - udelay (1000); /* 1ms */ - /* Unreset controller */ - out8 (IIC_XTCNTLSS, (status & ~IIC_XTCNTLSS_SRST)); - udelay (1000); /* 1ms */ + + /* Remove reset */ + out_8((u8 *)IIC_XTCNTLSS, 0); } -void i2c_init (int speed, int slaveadd) +void i2c_init(int speed, int slaveadd) { sys_info_t sysInfo; unsigned long freqOPB; int val, divisor; + int bus; #ifdef CFG_I2C_INIT_BOARD /* call board specific i2c bus reset routine before accessing the */ @@ -94,101 +103,100 @@ void i2c_init (int speed, int slaveadd) i2c_init_board(); #endif - /* Handle possible failed I2C state */ - /* FIXME: put this into i2c_init_board()? */ - _i2c_bus_reset (); + for (bus = 0; bus < CFG_MAX_I2C_BUS; bus++) { + I2C_SET_BUS(bus); - /* clear lo master address */ - out8 (IIC_LMADR, 0); + /* Handle possible failed I2C state */ + /* FIXME: put this into i2c_init_board()? */ + _i2c_bus_reset(); - /* clear hi master address */ - out8 (IIC_HMADR, 0); + /* clear lo master address */ + out_8((u8 *)IIC_LMADR, 0); - /* clear lo slave address */ - out8 (IIC_LSADR, 0); + /* clear hi master address */ + out_8((u8 *)IIC_HMADR, 0); - /* clear hi slave address */ - out8 (IIC_HSADR, 0); + /* clear lo slave address */ + out_8((u8 *)IIC_LSADR, 0); - /* Clock divide Register */ - /* get OPB frequency */ - get_sys_info (&sysInfo); - freqOPB = sysInfo.freqPLB / sysInfo.pllOpbDiv; - /* set divisor according to freqOPB */ - divisor = (freqOPB - 1) / 10000000; - if (divisor == 0) - divisor = 1; - out8 (IIC_CLKDIV, divisor); + /* clear hi slave address */ + out_8((u8 *)IIC_HSADR, 0); - /* no interrupts */ - out8 (IIC_INTRMSK, 0); + /* Clock divide Register */ + /* get OPB frequency */ + get_sys_info(&sysInfo); + freqOPB = sysInfo.freqPLB / sysInfo.pllOpbDiv; + /* set divisor according to freqOPB */ + divisor = (freqOPB - 1) / 10000000; + if (divisor == 0) + divisor = 1; + out_8((u8 *)IIC_CLKDIV, divisor); - /* clear transfer count */ - out8 (IIC_XFRCNT, 0); + /* no interrupts */ + out_8((u8 *)IIC_INTRMSK, 0); - /* clear extended control & stat */ - /* write 1 in SRC SRS SWC SWS to clear these fields */ - out8 (IIC_XTCNTLSS, 0xF0); + /* clear transfer count */ + out_8((u8 *)IIC_XFRCNT, 0); - /* Mode Control Register - Flush Slave/Master data buffer */ - out8 (IIC_MDCNTL, IIC_MDCNTL_FSDB | IIC_MDCNTL_FMDB); - __asm__ volatile ("eieio"); + /* clear extended control & stat */ + /* write 1 in SRC SRS SWC SWS to clear these fields */ + out_8((u8 *)IIC_XTCNTLSS, 0xF0); + /* Mode Control Register + Flush Slave/Master data buffer */ + out_8((u8 *)IIC_MDCNTL, IIC_MDCNTL_FSDB | IIC_MDCNTL_FMDB); - val = in8(IIC_MDCNTL); - __asm__ volatile ("eieio"); + val = in_8((u8 *)IIC_MDCNTL); - /* Ignore General Call, slave transfers are ignored, - disable interrupts, exit unknown bus state, enable hold - SCL - 100kHz normaly or FastMode for 400kHz and above - */ + /* Ignore General Call, slave transfers are ignored, + * disable interrupts, exit unknown bus state, enable hold + * SCL 100kHz normaly or FastMode for 400kHz and above + */ - val |= IIC_MDCNTL_EUBS|IIC_MDCNTL_HSCL; - if( speed >= 400000 ){ - val |= IIC_MDCNTL_FSM; - } - out8 (IIC_MDCNTL, val); + val |= IIC_MDCNTL_EUBS|IIC_MDCNTL_HSCL; + if (speed >= 400000) + val |= IIC_MDCNTL_FSM; + out_8((u8 *)IIC_MDCNTL, val); - /* clear control reg */ - out8 (IIC_CNTL, 0x00); - __asm__ volatile ("eieio"); + /* clear control reg */ + out_8((u8 *)IIC_CNTL, 0x00); + } + /* set to SPD bus as default bus upon powerup */ + I2C_SET_BUS(CFG_SPD_BUS_NUM); } /* - This code tries to use the features of the 405GP i2c - controller. It will transfer up to 4 bytes in one pass - on the loop. It only does out8(lbz) to the buffer when it - is possible to do out16(lhz) transfers. - - cmd_type is 0 for write 1 for read. - - addr_len can take any value from 0-255, it is only limited - by the char, we could make it larger if needed. If it is - 0 we skip the address write cycle. - - Typical case is a Write of an addr followd by a Read. The - IBM FAQ does not cover this. On the last byte of the write - we don't set the creg CHT bit, and on the first bytes of the - read we set the RPST bit. - - It does not support address only transfers, there must be - a data part. If you want to write the address yourself, put - it in the data pointer. - - It does not support transfer to/from address 0. - - It does not check XFRCNT. -*/ -static -int i2c_transfer(unsigned char cmd_type, - unsigned char chip, - unsigned char addr[], - unsigned char addr_len, - unsigned char data[], - unsigned short data_len ) + * This code tries to use the features of the 405GP i2c + * controller. It will transfer up to 4 bytes in one pass + * on the loop. It only does out_8((u8 *)lbz) to the buffer when it + * is possible to do out16(lhz) transfers. + * + * cmd_type is 0 for write 1 for read. + * + * addr_len can take any value from 0-255, it is only limited + * by the char, we could make it larger if needed. If it is + * 0 we skip the address write cycle. + * + * Typical case is a Write of an addr followd by a Read. The + * IBM FAQ does not cover this. On the last byte of the write + * we don't set the creg CHT bit, and on the first bytes of the + * read we set the RPST bit. + * + * It does not support address only transfers, there must be + * a data part. If you want to write the address yourself, put + * it in the data pointer. + * + * It does not support transfer to/from address 0. + * + * It does not check XFRCNT. + */ +static int i2c_transfer(unsigned char cmd_type, + unsigned char chip, + unsigned char addr[], + unsigned char addr_len, + unsigned char data[], + unsigned short data_len) { unsigned char* ptr; int reading; @@ -198,97 +206,88 @@ int i2c_transfer(unsigned char cmd_type, int i; uchar creg; - if( data == 0 || data_len == 0 ){ - /*Don't support data transfer of no length or to address 0*/ + if (data == 0 || data_len == 0) { + /* Don't support data transfer of no length or to address 0 */ printf( "i2c_transfer: bad call\n" ); return IIC_NOK; } - if( addr && addr_len ){ + if (addr && addr_len) { ptr = addr; cnt = addr_len; reading = 0; - }else{ + } else { ptr = data; cnt = data_len; reading = cmd_type; } - /*Clear Stop Complete Bit*/ - out8(IIC_STS,IIC_STS_SCMP); + /* Clear Stop Complete Bit */ + out_8((u8 *)IIC_STS, IIC_STS_SCMP); /* Check init */ - i=10; + i = 10; do { /* Get status */ - status = in8(IIC_STS); - __asm__ volatile("eieio"); + status = in_8((u8 *)IIC_STS); i--; - } while ((status & IIC_STS_PT) && (i>0)); + } while ((status & IIC_STS_PT) && (i > 0)); if (status & IIC_STS_PT) { result = IIC_NOK_TOUT; return(result); } - /*flush the Master/Slave Databuffers*/ - out8(IIC_MDCNTL, ((in8(IIC_MDCNTL))|IIC_MDCNTL_FMDB|IIC_MDCNTL_FSDB)); - /*need to wait 4 OPB clocks? code below should take that long*/ + /* flush the Master/Slave Databuffers */ + out_8((u8 *)IIC_MDCNTL, ((in_8((u8 *)IIC_MDCNTL))|IIC_MDCNTL_FMDB|IIC_MDCNTL_FSDB)); + /* need to wait 4 OPB clocks? code below should take that long */ /* 7-bit adressing */ - out8(IIC_HMADR,0); - out8(IIC_LMADR, chip); - __asm__ volatile("eieio"); + out_8((u8 *)IIC_HMADR, 0); + out_8((u8 *)IIC_LMADR, chip); tran = 0; result = IIC_OK; creg = 0; - while ( tran != cnt && (result == IIC_OK)) { + while (tran != cnt && (result == IIC_OK)) { int bc,j; /* Control register = - Normal transfer, 7-bits adressing, Transfer up to bc bytes, Normal start, - Transfer is a sequence of transfers - */ + * Normal transfer, 7-bits adressing, Transfer up to bc bytes, Normal start, + * Transfer is a sequence of transfers + */ creg |= IIC_CNTL_PT; - bc = (cnt - tran) > 4 ? 4 : - cnt - tran; - creg |= (bc-1)<<4; - /* if the real cmd type is write continue trans*/ - if ( (!cmd_type && (ptr == addr)) || ((tran+bc) != cnt) ) + bc = (cnt - tran) > 4 ? 4 : cnt - tran; + creg |= (bc - 1) << 4; + /* if the real cmd type is write continue trans */ + if ((!cmd_type && (ptr == addr)) || ((tran + bc) != cnt)) creg |= IIC_CNTL_CHT; if (reading) creg |= IIC_CNTL_READ; - else { - for(j=0; j0)); + } while ((status & IIC_STS_PT) && !(status & IIC_STS_ERR) && (i > 0)); if (status & IIC_STS_ERR) { result = IIC_NOK; - status = in8 (IIC_EXTSTS); + status = in_8((u8 *)IIC_EXTSTS); /* Lost arbitration? */ if (status & IIC_EXTSTS_LA) result = IIC_NOK_LA; @@ -306,34 +305,32 @@ int i2c_transfer(unsigned char cmd_type, /* Are there data in buffer */ if (status & IIC_STS_MDBS) { /* - even if we have data we have to wait 4OPB clocks - for it to hit the front of the FIFO, after that - we can just read. We should check XFCNT here and - if the FIFO is full there is no need to wait. - */ - udelay (1); - for(j=0;jed (i.e. there was a chip at that address which * drove the data line low). */ - return(i2c_transfer (1, chip << 1, 0,0, buf, 1) != 0); + return (i2c_transfer(1, chip << 1, 0,0, buf, 1) != 0); } -int i2c_read (uchar chip, uint addr, int alen, uchar * buffer, int len) +int i2c_read(uchar chip, uint addr, int alen, uchar * buffer, int len) { uchar xaddr[4]; int ret; - if ( alen > 4 ) { + if (alen > 4) { printf ("I2C read: addr len %d not supported\n", alen); return 1; } - if ( alen > 0 ) { + if (alen > 0) { xaddr[0] = (addr >> 24) & 0xFF; xaddr[1] = (addr >> 16) & 0xFF; xaddr[2] = (addr >> 8) & 0xFF; @@ -378,10 +375,10 @@ int i2c_read (uchar chip, uint addr, int alen, uchar * buffer, int len) * still be one byte because the extra address bits are * hidden in the chip address. */ - if( alen > 0 ) + if (alen > 0) chip |= ((addr >> (alen * 8)) & CFG_I2C_EEPROM_ADDR_OVERFLOW); #endif - if( (ret = i2c_transfer( 1, chip<<1, &xaddr[4-alen], alen, buffer, len )) != 0) { + if ((ret = i2c_transfer(1, chip<<1, &xaddr[4-alen], alen, buffer, len)) != 0) { if (gd->have_console) printf( "I2c read: failed %d\n", ret); return 1; @@ -389,16 +386,17 @@ int i2c_read (uchar chip, uint addr, int alen, uchar * buffer, int len) return 0; } -int i2c_write (uchar chip, uint addr, int alen, uchar * buffer, int len) +int i2c_write(uchar chip, uint addr, int alen, uchar * buffer, int len) { uchar xaddr[4]; - if ( alen > 4 ) { + if (alen > 4) { printf ("I2C write: addr len %d not supported\n", alen); return 1; } - if ( alen > 0 ) { + + if (alen > 0) { xaddr[0] = (addr >> 24) & 0xFF; xaddr[1] = (addr >> 16) & 0xFF; xaddr[2] = (addr >> 8) & 0xFF; @@ -417,11 +415,11 @@ int i2c_write (uchar chip, uint addr, int alen, uchar * buffer, int len) * still be one byte because the extra address bits are * hidden in the chip address. */ - if( alen > 0 ) + if (alen > 0) chip |= ((addr >> (alen * 8)) & CFG_I2C_EEPROM_ADDR_OVERFLOW); #endif - return (i2c_transfer( 0, chip<<1, &xaddr[4-alen], alen, buffer, len ) != 0); + return (i2c_transfer(0, chip<<1, &xaddr[4-alen], alen, buffer, len ) != 0); } /*----------------------------------------------------------------------- @@ -433,7 +431,7 @@ uchar i2c_reg_read(uchar i2c_addr, uchar reg) i2c_read(i2c_addr, reg, 1, &buf, 1); - return(buf); + return (buf); } /*----------------------------------------------------------------------- @@ -443,4 +441,38 @@ void i2c_reg_write(uchar i2c_addr, uchar reg, uchar val) { i2c_write(i2c_addr, reg, 1, &val, 1); } + +#if defined(CONFIG_I2C_MULTI_BUS) +/* + * Functions for multiple I2C bus handling + */ +unsigned int i2c_get_bus_num(void) +{ + return i2c_bus_num; +} + +int i2c_set_bus_num(unsigned int bus) +{ + if (bus >= CFG_MAX_I2C_BUS) + return -1; + + i2c_bus_num = bus; + + return 0; +} + +/* TODO: add 100/400k switching */ +unsigned int i2c_get_bus_speed(void) +{ + return CFG_I2C_SPEED; +} + +int i2c_set_bus_speed(unsigned int speed) +{ + if (speed != CFG_I2C_SPEED) + return -1; + + return 0; +} +#endif /* CONFIG_I2C_MULTI_BUS */ #endif /* CONFIG_HARD_I2C */ -- cgit v1.2.1