diff options
Diffstat (limited to 'cpu')
| -rw-r--r-- | cpu/mpc5xxx/Makefile | 2 | ||||
| -rw-r--r-- | cpu/mpc5xxx/i2c.c | 338 |
2 files changed, 339 insertions, 1 deletions
diff --git a/cpu/mpc5xxx/Makefile b/cpu/mpc5xxx/Makefile index 74ec64c..a65bc22 100644 --- a/cpu/mpc5xxx/Makefile +++ b/cpu/mpc5xxx/Makefile @@ -27,7 +27,7 @@ LIB = lib$(CPU).a START = start.o ASOBJS = io.o firmware_sc_task_bestcomm.impl.o firmware_sc_task.impl.o -OBJS = traps.o cpu.o cpu_init.o speed.o interrupts.o serial.o \ +OBJS = i2c.o traps.o cpu.o cpu_init.o speed.o interrupts.o serial.o \ loadtask.o fec.o pci_mpc5200.o all: .depend $(START) $(ASOBJS) $(LIB) diff --git a/cpu/mpc5xxx/i2c.c b/cpu/mpc5xxx/i2c.c new file mode 100644 index 0000000..640d140 --- /dev/null +++ b/cpu/mpc5xxx/i2c.c @@ -0,0 +1,338 @@ +/* + * (C) Copyright 2003 + * Wolfgang Denk, DENX Software Engineering, wd@denx.de. + * + * 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_HARD_I2C + +#include <mpc5xxx.h> +#include <i2c.h> + +#ifdef CFG_I2C_MODULE +#define I2C_BASE MPC5XXX_I2C2 +#else +#define I2C_BASE MPC5XXX_I2C1 +#endif + +#define I2C_TIMEOUT 100 +#define I2C_RETRIES 3 + +static int mpc_reg_in (volatile u32 *reg); +static void mpc_reg_out (volatile u32 *reg, int val, int mask); +static int wait_for_bb (void); +static int wait_for_pin (int *status); +static int do_address (uchar chip, char rdwr_flag); +static int send_bytes (uchar chip, char *buf, int len); +static int receive_bytes (uchar chip, char *buf, int len); + +static int mpc_reg_in(volatile u32 *reg) +{ + return *reg >> 24; + __asm__ __volatile__ ("eieio"); +} + +static void mpc_reg_out(volatile u32 *reg, int val, int mask) +{ + int tmp; + + if (!mask) { + *reg = val << 24; + } else { + tmp = mpc_reg_in(reg); + *reg = ((tmp & ~mask) | (val & mask)) << 24; + } + __asm__ __volatile__ ("eieio"); + + return; +} + +static int wait_for_bb(void) +{ + struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; + int timeout = I2C_TIMEOUT; + int status; + + status = mpc_reg_in(®s->msr); + + while (timeout-- && (status & I2C_BB)) { +#if 1 + volatile int temp; + mpc_reg_out(®s->mcr, I2C_STA, I2C_STA); + temp = mpc_reg_in(®s->mdr); + mpc_reg_out(®s->mcr, 0, I2C_STA); + mpc_reg_out(®s->mcr, 0, 0); + mpc_reg_out(®s->mcr, I2C_EN, 0); +#endif + udelay(1000); + status = mpc_reg_in(®s->msr); + } + + return (status & I2C_BB); +} + +static int wait_for_pin(int *status) +{ + struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; + int timeout = I2C_TIMEOUT; + + *status = mpc_reg_in(®s->msr); + + while (timeout-- && !(*status & I2C_IF)) { + udelay(1000); + *status = mpc_reg_in(®s->msr); + } + + if (!(*status & I2C_IF)) { + return -1; + } + + mpc_reg_out(®s->msr, 0, I2C_IF); + + return 0; +} + +static int do_address(uchar chip, char rdwr_flag) +{ + struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; + int status; + + chip <<= 1; + + if (rdwr_flag) { + chip |= 1; + } + + mpc_reg_out(®s->mcr, I2C_TX, I2C_TX); + mpc_reg_out(®s->mdr, chip, 0); + + if (wait_for_pin(&status)) { + return -2; + } + + if (status & I2C_RXAK) { + return -3; + } + + return 0; +} + +static int send_bytes(uchar chip, char *buf, int len) +{ + struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; + int wrcount; + int status; + + for (wrcount = 0; wrcount < len; ++wrcount) { + + mpc_reg_out(®s->mdr, buf[wrcount], 0); + + if (wait_for_pin(&status)) { + break; + } + + if (status & I2C_RXAK) { + break; + } + + } + + return !(wrcount == len); +} + +static int receive_bytes(uchar chip, char *buf, int len) +{ + struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; + int dummy = 1; + int rdcount = 0; + int status; + int i; + + mpc_reg_out(®s->mcr, 0, I2C_TX); + + for (i = 0; i < len; ++i) { + buf[rdcount] = mpc_reg_in(®s->mdr); + + if (dummy) { + dummy = 0; + } else { + rdcount++; + } + + + if (wait_for_pin(&status)) { + return -4; + } + } + + mpc_reg_out(®s->mcr, I2C_TXAK, I2C_TXAK); + buf[rdcount++] = mpc_reg_in(®s->mdr); + + if (wait_for_pin(&status)) { + return -5; + } + + mpc_reg_out(®s->mcr, 0, I2C_TXAK); + + return 0; +} + +/**************** I2C API ****************/ + +void i2c_init(int speed, int saddr) +{ + struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; + + mpc_reg_out(®s->mcr, 0, 0); + mpc_reg_out(®s->madr, saddr << 1, 0); + + /* Set clock + */ + mpc_reg_out(®s->mfdr, speed, 0); + + /* Enable module + */ + mpc_reg_out(®s->mcr, I2C_EN, I2C_INIT_MASK); + mpc_reg_out(®s->msr, 0, I2C_IF); + + return; +} + +int i2c_probe(uchar chip) +{ + struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; + int i; + + for (i = 0; i < I2C_RETRIES; i++) { + mpc_reg_out(®s->mcr, I2C_STA, I2C_STA); + + if (! do_address(chip, 0)) { + mpc_reg_out(®s->mcr, 0, I2C_STA); + break; + } + + mpc_reg_out(®s->mcr, 0, I2C_STA); + udelay(500); + } + + return (i == I2C_RETRIES); +} + +int i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len) +{ + uchar xaddr[4]; + struct mpc5xxx_i2c * regs = (struct mpc5xxx_i2c *)I2C_BASE; + int ret = -1; + + xaddr[0] = (addr >> 24) & 0xFF; + xaddr[1] = (addr >> 16) & 0xFF; + xaddr[2] = (addr >> 8) & 0xFF; + xaddr[3] = addr & 0xFF; + + if (wait_for_bb()) { + printf("i2c_read: bus is busy\n"); + goto Done; + } + + mpc_reg_out(®s->mcr, I2C_STA, I2C_STA); + if (do_address(chip, 0)) { + printf("i2c_read: failed to address chip\n"); + goto Done; + } + + if (send_bytes(chip, &xaddr[4-alen], alen)) { + printf("i2c_read: send_bytes failed\n"); + goto Done; + } + + mpc_reg_out(®s->mcr, I2C_RSTA, I2C_RSTA); + if (do_address(chip, 1)) { + printf("i2c_read: failed to address chip\n"); + goto Done; + } + + if (receive_bytes(chip, buf, len)) { + printf("i2c_read: receive_bytes failed\n"); + goto Done; + } + + ret = 0; +Done: + mpc_reg_out(®s->mcr, 0, I2C_STA); + return ret; +} + +int i2c_write(uchar chip, uint addr, int alen, uchar *buf, int len) +{ + uchar xaddr[4]; + struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; + int ret = -1; + + xaddr[0] = (addr >> 24) & 0xFF; + xaddr[1] = (addr >> 16) & 0xFF; + xaddr[2] = (addr >> 8) & 0xFF; + xaddr[3] = addr & 0xFF; + + if (wait_for_bb()) { + printf("i2c_write: bus is busy\n"); + goto Done; + } + + mpc_reg_out(®s->mcr, I2C_STA, I2C_STA); + if (do_address(chip, 0)) { + printf("i2c_write: failed to address chip\n"); + goto Done; + } + + if (send_bytes(chip, &xaddr[4-alen], alen)) { + printf("i2c_write: send_bytes failed\n"); + goto Done; + } + + if (send_bytes(chip, buf, len)) { + printf("i2c_write: send_bytes failed\n"); + goto Done; + } + + ret = 0; +Done: + mpc_reg_out(®s->mcr, 0, I2C_STA); + return ret; +} + +uchar i2c_reg_read(uchar chip, uchar reg) +{ + char buf; + + i2c_read(chip, reg, 1, &buf, 1); + + return buf; +} + +void i2c_reg_write(uchar chip, uchar reg, uchar val) +{ + i2c_write(chip, reg, 1, &val, 1); + + return; +} + +#endif /* CONFIG_HARD_I2C */ |