summaryrefslogtreecommitdiff
path: root/cpu/ppc4xx/i2c.c
diff options
context:
space:
mode:
authorStefan Roese <sr@denx.de>2007-02-20 10:27:08 +0100
committerStefan Roese <sr@denx.de>2007-02-20 10:27:08 +0100
commit79b2d0bb2eae09602448f7a7cb56530d2f31e6c6 (patch)
treeec226ccf8314e37981f946df4391446a6ff9dc11 /cpu/ppc4xx/i2c.c
parent7372ca68227930d03cffa548310524cad5b96733 (diff)
[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 <sr@denx.de>
Diffstat (limited to 'cpu/ppc4xx/i2c.c')
-rw-r--r--cpu/ppc4xx/i2c.c458
1 files changed, 245 insertions, 213 deletions
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 <anne-sophie.harnois@nextream.fr>
+ *
+ * (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 <common.h>
#include <ppc4xx.h>
-#if defined(CONFIG_440)
-# include <440_i2c.h>
-#else
-# include <405gp_i2c.h>
-#endif
+#include <4xx_i2c.h>
#include <i2c.h>
+#include <asm-ppc/io.h>
#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; j<bc; j++) {
+ else
+ for(j=0; j < bc; j++)
/* Set buffer */
- out8(IIC_MDBUF,ptr[tran+j]);
- __asm__ volatile("eieio");
- }
- }
- out8(IIC_CNTL, creg );
- __asm__ volatile("eieio");
+ out_8((u8 *)IIC_MDBUF, ptr[tran+j]);
+ out_8((u8 *)IIC_CNTL, creg);
/* 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;
+ * 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_STS);
- __asm__ volatile("eieio");
- udelay (10);
+ status = in_8((u8 *)IIC_STS);
+ udelay(10);
i--;
- } while ((status & IIC_STS_PT) && !(status & IIC_STS_ERR)
- && (i>0));
+ } 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;j<bc;j++) {
- ptr[tran+j] = in8(IIC_MDBUF);
- __asm__ volatile("eieio");
- }
+ * 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] = in_8((u8 *)IIC_MDBUF);
} else
result = IIC_NOK_DATA;
}
creg = 0;
- tran+=bc;
- if( ptr == addr && tran == cnt ) {
+ tran += bc;
+ if (ptr == addr && tran == cnt) {
ptr = data;
cnt = data_len;
tran = 0;
reading = cmd_type;
- if( reading )
+ if (reading)
creg = IIC_CNTL_RPST;
}
}
return (result);
}
-int i2c_probe (uchar chip)
+int i2c_probe(uchar chip)
{
uchar buf[1];
@@ -344,21 +341,21 @@ int i2c_probe (uchar chip)
* address was <ACK>ed (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 */