diff options
Diffstat (limited to 'board/sandburst/common/ppc440gx_i2c.c')
| -rw-r--r-- | board/sandburst/common/ppc440gx_i2c.c | 515 | 
1 files changed, 515 insertions, 0 deletions
| diff --git a/board/sandburst/common/ppc440gx_i2c.c b/board/sandburst/common/ppc440gx_i2c.c new file mode 100644 index 000000000..c3b267c49 --- /dev/null +++ b/board/sandburst/common/ppc440gx_i2c.c @@ -0,0 +1,515 @@ +/* + *  Copyright (C) 2005 Sandburst Corporation + * + * 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 + */ + +/* + * Ported from cpu/ppc4xx/i2c.c by AS HARNOIS by + * Travis B. Sawyer + * Sandburst Corporation. + */ +#include <common.h> +#include <ppc4xx.h> +#if defined(CONFIG_440) +#   include <440_i2c.h> +#else +#   include <405gp_i2c.h> +#endif +#include <i2c.h> +#include <440_i2c.h> +#include <command.h> +#include "ppc440gx_i2c.h" + +#ifdef CONFIG_I2C_BUS1 + + + +#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 second */ +#if defined(CFG_I2C_NOPROBES) +static uchar i2c_no_probes[] = CFG_I2C_NOPROBES; +#endif + +static void _i2c_bus1_reset (void) +{ +	int i, status; + +	/* Reset status register */ +	/* write 1 in SCMP and IRQA to clear these fields */ +	out8 (IIC_STS1, 0x0A); + +	/* write 1 in IRQP IRQD LA ICT XFRA to clear these fields */ +	out8 (IIC_EXTSTS1, 0x8F); +	__asm__ volatile ("eieio"); + +	/* +	 * Get current state, reset bus +	 * only if no transfers are pending. +	 */ +	i = 10; +	do { +		/* Get status */ +		status = in8 (IIC_STS1); +		udelay (500);			/* 500us */ +		i--; +	} while ((status & IIC_STS_PT) && (i > 0)); +	/* Soft reset controller */ +	status = in8 (IIC_XTCNTLSS1); +	out8 (IIC_XTCNTLSS1, (status | IIC_XTCNTLSS_SRST)); +	__asm__ volatile ("eieio"); + +	/* make sure where in initial state, data hi, clock hi */ +	out8 (IIC_DIRECTCNTL1, 0xC); +	for (i = 0; i < 10; i++) { +		if ((in8 (IIC_DIRECTCNTL1) & 0x3) != 0x3) { +			/* clock until we get to known state */ +			out8 (IIC_DIRECTCNTL1, 0x8);	/* clock lo */ +			udelay (100);		/* 100us */ +			out8 (IIC_DIRECTCNTL1, 0xC);	/* clock hi */ +			udelay (100);		/* 100us */ +		} else { +			break; +		} +	} +	/* send start condition */ +	out8 (IIC_DIRECTCNTL1, 0x4); +	udelay (1000);				/* 1ms */ +	/* send stop condition */ +	out8 (IIC_DIRECTCNTL1, 0xC); +	udelay (1000);				/* 1ms */ +	/* Unreset controller */ +	out8 (IIC_XTCNTLSS1, (status & ~IIC_XTCNTLSS_SRST)); +	udelay (1000);				/* 1ms */ +} + +void i2c1_init (int speed, int slaveadd) +{ +	sys_info_t sysInfo; +	unsigned long freqOPB; +	int val, divisor; + +#ifdef CFG_I2C_INIT_BOARD +	/* call board specific i2c bus reset routine before accessing the   */ +	/* environment, which might be in a chip on that bus. For details   */ +	/* about this problem see doc/I2C_Edge_Conditions.                  */ +	i2c_init_board(); +#endif + +	/* Handle possible failed I2C state */ +	/* FIXME: put this into i2c_init_board()? */ +	_i2c_bus1_reset (); + +	/* clear lo master address */ +	out8 (IIC_LMADR1, 0); + +	/* clear hi master address */ +	out8 (IIC_HMADR1, 0); + +	/* clear lo slave address */ +	out8 (IIC_LSADR1, 0); + +	/* clear hi slave address */ +	out8 (IIC_HSADR1, 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_CLKDIV1, divisor); + +	/* no interrupts */ +	out8 (IIC_INTRMSK1, 0); + +	/* clear transfer count */ +	out8 (IIC_XFRCNT1, 0); + +	/* clear extended control & stat */ +	/* write 1 in SRC SRS SWC SWS to clear these fields */ +	out8 (IIC_XTCNTLSS1, 0xF0); + +	/* Mode Control Register +	   Flush Slave/Master data buffer */ +	out8 (IIC_MDCNTL1, IIC_MDCNTL_FSDB | IIC_MDCNTL_FMDB); +	__asm__ volatile ("eieio"); + + +	val = in8(IIC_MDCNTL1); +	__asm__ volatile ("eieio"); + +	/* 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_MDCNTL1, val); + +	/* clear control reg */ +	out8 (IIC_CNTL1, 0x00); +	__asm__ volatile ("eieio"); + +} + +/* +  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_transfer1(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; +	int tran,cnt; +	int result; +	int status; +	int i; +	uchar creg; + +	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 ){ +		ptr = addr; +		cnt = addr_len; +		reading = 0; +	}else{ +		ptr = data; +		cnt = data_len; +		reading = cmd_type; +	} + +	/*Clear Stop Complete Bit*/ +	out8(IIC_STS1,IIC_STS_SCMP); +	/* Check init */ +	i=10; +	do { +		/* Get status */ +		status = in8(IIC_STS1); +		__asm__ volatile("eieio"); +		i--; +	} 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_MDCNTL1, ((in8(IIC_MDCNTL1))|IIC_MDCNTL_FMDB|IIC_MDCNTL_FSDB)); +	/*need to wait 4 OPB clocks? code below should take that long*/ + +	/* 7-bit adressing */ +	out8(IIC_HMADR1,0); +	out8(IIC_LMADR1, chip); +	__asm__ volatile("eieio"); + +	tran = 0; +	result = IIC_OK; +	creg = 0; + +	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 +		*/ +		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) ) +			creg |= IIC_CNTL_CHT; + +		if (reading) +			creg |= IIC_CNTL_READ; +		else { +			for(j=0; j<bc; j++) { +				/* Set buffer */ +				out8(IIC_MDBUF1,ptr[tran+j]); +				__asm__ volatile("eieio"); +			} +		} +		out8(IIC_CNTL1, creg ); +		__asm__ volatile("eieio"); + +		/* Transfer is in progress +		   we have to wait for upto 5 bytes of data +		   1 byte chip address+r/w bit then bc bytes +		   of data. +		   udelay(10) is 1 bit time at 100khz +		   Doubled for slop. 20 is too small. +		*/ +		i=2*5*8; +		do { +			/* Get status */ +			status = in8(IIC_STS1); +			__asm__ volatile("eieio"); +			udelay (10); +			i--; +		} while ((status & IIC_STS_PT) && !(status & IIC_STS_ERR) +			 && (i>0)); + +		if (status & IIC_STS_ERR) { +			result = IIC_NOK; +			status = in8 (IIC_EXTSTS1); +			/* Lost arbitration? */ +			if (status & IIC_EXTSTS_LA) +				result = IIC_NOK_LA; +			/* Incomplete transfer? */ +			if (status & IIC_EXTSTS_ICT) +				result = IIC_NOK_ICT; +			/* Transfer aborted? */ +			if (status & IIC_EXTSTS_XFRA) +				result = IIC_NOK_XFRA; +		} else if ( status & IIC_STS_PT) { +			result = IIC_NOK_TOUT; +		} +		/* Command is reading => get buffer */ +		if ((reading) && (result == IIC_OK)) { +			/* 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;j<bc;j++) { +					ptr[tran+j] = in8(IIC_MDBUF1); +					__asm__ volatile("eieio"); +				} +			} else +				result = IIC_NOK_DATA; +		} +		creg = 0; +		tran+=bc; +		if( ptr == addr && tran == cnt ) { +			ptr = data; +			cnt = data_len; +			tran = 0; +			reading = cmd_type; +			if( reading ) +				creg = IIC_CNTL_RPST; +		} +	} +	return (result); +} + +int i2c_probe1 (uchar chip) +{ +	uchar buf[1]; + +	buf[0] = 0; + +	/* +	 * What is needed is to send the chip address and verify that the +	 * address was <ACK>ed (i.e. there was a chip at that address which +	 * drove the data line low). +	 */ +	return(i2c_transfer1 (1, chip << 1, 0,0, buf, 1) != 0); +} + + +int i2c_read1 (uchar chip, uint addr, int alen, uchar * buffer, int len) +{ +	uchar xaddr[4]; +	int ret; + +	if ( alen > 4 ) { +		printf ("I2C read: addr len %d not supported\n", alen); +		return 1; +	} + +	if ( alen > 0 ) { +		xaddr[0] = (addr >> 24) & 0xFF; +		xaddr[1] = (addr >> 16) & 0xFF; +		xaddr[2] = (addr >> 8) & 0xFF; +		xaddr[3] = addr & 0xFF; +	} + + +#ifdef CFG_I2C_EEPROM_ADDR_OVERFLOW +	/* +	 * EEPROM chips that implement "address overflow" are ones +	 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of +	 * address and the extra bits end up in the "chip address" +	 * bit slots. This makes a 24WC08 (1Kbyte) chip look like +	 * four 256 byte chips. +	 * +	 * Note that we consider the length of the address field to +	 * still be one byte because the extra address bits are +	 * hidden in the chip address. +	 */ +	if( alen > 0 ) +		chip |= ((addr >> (alen * 8)) & CFG_I2C_EEPROM_ADDR_OVERFLOW); +#endif +	if( (ret = i2c_transfer1( 1, chip<<1, &xaddr[4-alen], alen, buffer, len )) != 0) { +		printf( "I2c read: failed %d\n", ret); +		return 1; +	} +	return 0; +} + +int i2c_write1 (uchar chip, uint addr, int alen, uchar * buffer, int len) +{ +	uchar xaddr[4]; + +	if ( alen > 4 ) { +		printf ("I2C write: addr len %d not supported\n", alen); +		return 1; + +	} +	if ( alen > 0 ) { +		xaddr[0] = (addr >> 24) & 0xFF; +		xaddr[1] = (addr >> 16) & 0xFF; +		xaddr[2] = (addr >> 8) & 0xFF; +		xaddr[3] = addr & 0xFF; +	} + +#ifdef CFG_I2C_EEPROM_ADDR_OVERFLOW +	/* +	 * EEPROM chips that implement "address overflow" are ones +	 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of +	 * address and the extra bits end up in the "chip address" +	 * bit slots. This makes a 24WC08 (1Kbyte) chip look like +	 * four 256 byte chips. +	 * +	 * Note that we consider the length of the address field to +	 * still be one byte because the extra address bits are +	 * hidden in the chip address. +	 */ +	if( alen > 0 ) +		chip |= ((addr >> (alen * 8)) & CFG_I2C_EEPROM_ADDR_OVERFLOW); +#endif + +	return (i2c_transfer1( 0, chip<<1, &xaddr[4-alen], alen, buffer, len ) != 0); +} + +/*----------------------------------------------------------------------- + * Read a register + */ +uchar i2c_reg_read1(uchar i2c_addr, uchar reg) +{ +	char buf; + +	i2c_read1(i2c_addr, reg, 1, &buf, 1); + +	return(buf); +} + +/*----------------------------------------------------------------------- + * Write a register + */ +void i2c_reg_write1(uchar i2c_addr, uchar reg, uchar val) +{ +	i2c_write1(i2c_addr, reg, 1, &val, 1); +} + + +int do_i2c1_probe(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +{ +	int j; +#if defined(CFG_I2C_NOPROBES) +	int k, skip; +#endif + +	puts ("Valid chip addresses:"); +	for(j = 0; j < 128; j++) { +#if defined(CFG_I2C_NOPROBES) +		skip = 0; +		for (k = 0; k < sizeof(i2c_no_probes); k++){ +			if (j == i2c_no_probes[k]){ +				skip = 1; +				break; +			} +		} +		if (skip) +			continue; +#endif +		if(i2c_probe1(j) == 0) { +			printf(" %02X", j); +		} +	} +	putc ('\n'); + +#if defined(CFG_I2C_NOPROBES) +	puts ("Excluded chip addresses:"); +	for( k = 0; k < sizeof(i2c_no_probes); k++ ) +		printf(" %02X", i2c_no_probes[k] ); +	putc ('\n'); +#endif + +	return 0; +} + +U_BOOT_CMD( +	iprobe1,	1,	1,	do_i2c1_probe, +	"iprobe1  - probe to discover valid I2C chip addresses\n", +	"\n    -discover valid I2C chip addresses\n" +); + +#endif + |