soc/intel/quark: Fix I2C driver

Fix the following issues:
*  A raw read is described by a single read segment, don't assert.
*  Support reads longer than the FIFO size.
*  Support writes longer than the FIFO size.
*  Use the 400 KHz clock by default.
*  Remove the error displays since vboot device polling generates
   errors.

TEST=Build and run on Galileo Gen2

Change-Id: I421ebb23989aa283b5182dcae4f8099c9ec16eee
Signed-off-by: Lee Leahy <leroy.p.leahy@intel.com>
Reviewed-on: https://review.coreboot.org/18029
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
This commit is contained in:
Lee Leahy 2017-01-03 16:00:15 -08:00
parent 2ea12e5ce0
commit 16568c7535
1 changed files with 201 additions and 75 deletions

View File

@ -1,7 +1,7 @@
/*
* This file is part of the coreboot project.
*
* Copyright (C) 2016 Intel Corporation.
* Copyright (C) 2016-2017 Intel Corporation.
*
* 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
@ -23,6 +23,7 @@
#include <soc/i2c.h>
#include <soc/ramstage.h>
#include <soc/reg_access.h>
#include <timer.h>
static void i2c_disable(I2C_REGS *regs)
{
@ -46,17 +47,144 @@ static void i2c_disable(I2C_REGS *regs)
status = regs->ic_clr_intr;
}
int platform_i2c_transfer(unsigned bus, struct i2c_seg *segments, int count)
static int platform_i2c_write(uint32_t restart, uint8_t *tx_buffer, int length,
uint32_t stop, uint8_t *rx_buffer, struct stopwatch *timeout)
{
int bytes_transferred;
uint32_t cmd;
I2C_REGS *regs;
uint32_t status;
ASSERT(tx_buffer != NULL);
ASSERT(timeout != NULL);
regs = get_i2c_address();
/* Fill the FIFO with the write operation */
bytes_transferred = 0;
do {
status = regs->ic_raw_intr_stat;
/* Check for errors */
if (status & (IC_INTR_RX_OVER | IC_INTR_RX_UNDER
| IC_INTR_TX_ABRT | IC_INTR_TX_OVER)) {
i2c_disable(regs);
return -1;
}
/* Check for timeout */
if (stopwatch_expired(timeout))
return -1;
/* Receive any available data */
status = regs->ic_status;
if (rx_buffer != NULL) {
while (status & IC_STATUS_RFNE) {
*rx_buffer++ = (uint8_t)regs->ic_data_cmd;
bytes_transferred++;
status = regs->ic_status;
}
}
/* Determine if space is available in the FIFO */
if (status & IC_STATUS_TFNF) {
/* End of the transaction? */
cmd = IC_DATA_CMD_WRITE | *tx_buffer++ | restart;
if (length == 1)
cmd |= stop;
restart = 0;
/* Place a data byte into the FIFO */
regs->ic_data_cmd = cmd;
length--;
bytes_transferred++;
} else
udelay(1);
} while (length > 0);
return bytes_transferred;
}
static int platform_i2c_read(uint32_t restart, uint8_t *rx_buffer, int length,
uint32_t stop, struct stopwatch *timeout)
{
int bytes_transferred;
uint32_t cmd;
int fifo_bytes;
uint8_t junk;
I2C_REGS *regs;
uint32_t status;
ASSERT(rx_buffer != NULL);
ASSERT(timeout != NULL);
regs = get_i2c_address();
/* Empty the FIFO */
status = regs->ic_status;
while (status & IC_STATUS_RFNE) {
junk = (uint8_t)regs->ic_data_cmd;
status = regs->ic_status;
}
/* Fill the FIFO with read commands */
fifo_bytes = min(length, 16);
bytes_transferred = 0;
while (length > 0) {
status = regs->ic_raw_intr_stat;
/* Check for errors */
if (status & (IC_INTR_RX_OVER | IC_INTR_RX_UNDER
| IC_INTR_TX_ABRT | IC_INTR_TX_OVER)) {
i2c_disable(regs);
return -1;
}
/* Check for timeout */
if (stopwatch_expired(timeout))
return -1;
/* Receive any available data */
status = regs->ic_status;
if (status & IC_STATUS_RFNE) {
/* Save the next data byte, removed from the RX FIFO */
*rx_buffer++ = (uint8_t)regs->ic_data_cmd;
bytes_transferred++;
}
if ((status & IC_STATUS_TFNF)
|| ((status & IC_STATUS_RFNE) && (fifo_bytes > 0))) {
/* End of the transaction? */
cmd = IC_DATA_CMD_READ | restart;
if (length == 1)
cmd |= stop;
restart = 0;
/* Place a read command into the TX FIFO */
regs->ic_data_cmd = cmd;
if (fifo_bytes > 0)
fifo_bytes--;
length--;
} else
udelay(1);
}
return bytes_transferred;
}
int platform_i2c_transfer(unsigned int bus, struct i2c_seg *segment,
int seg_count)
{
uint8_t *buffer;
int bytes_transferred;
uint8_t chip;
uint32_t cmd;
int data_bytes;
int length;
int read_length;
I2C_REGS *regs;
uint32_t restart;
uint8_t *rx_buffer;
uint32_t status;
uint32_t timeout;
uint32_t stop;
struct stopwatch timeout;
int total_bytes;
uint8_t *tx_buffer;
int tx_bytes;
regs = get_i2c_address();
@ -64,9 +192,8 @@ int platform_i2c_transfer(unsigned bus, struct i2c_seg *segments, int count)
i2c_disable(regs);
/* Set the slave address */
ASSERT (count > 0);
ASSERT (segments != NULL);
ASSERT (segments->read == 0);
ASSERT(seg_count > 0);
ASSERT(segment != NULL);
/* Clear the start and stop detection */
status = regs->ic_clr_start_det;
@ -75,12 +202,12 @@ int platform_i2c_transfer(unsigned bus, struct i2c_seg *segments, int count)
/* Set addressing mode to 7-bit and fast mode */
cmd = regs->ic_con;
cmd &= ~(IC_CON_10B | IC_CON_SPEED);
cmd |= IC_CON_RESTART_EN | IC_CON_7B | IC_CON_SPEED_100_KHz
cmd |= IC_CON_RESTART_EN | IC_CON_7B | IC_CON_SPEED_400_KHz
| IC_CON_MASTER_MODE;
regs->ic_con = cmd;
/* Set the target chip address */
chip = segments->chip;
chip = segment->chip;
regs->ic_tar = chip;
/* Enable the I2C controller */
@ -92,86 +219,85 @@ int platform_i2c_transfer(unsigned bus, struct i2c_seg *segments, int count)
status = regs->ic_clr_tx_over;
status = regs->ic_clr_tx_abrt;
/* Start the timeout */
stopwatch_init_msecs_expire(&timeout, 1000);
/* Process each of the segments */
total_bytes = 0;
tx_bytes = 0;
bytes_transferred = 0;
read_length = 0;
buffer = NULL;
while (count-- > 0) {
buffer = segments->buf;
length = segments->len;
ASSERT (buffer != NULL);
ASSERT (length >= 1);
ASSERT (segments->chip == chip);
rx_buffer = NULL;
restart = 0;
while (seg_count-- > 0) {
length = segment->len;
total_bytes += length;
ASSERT(segment->buf != NULL);
ASSERT(length >= 1);
ASSERT(segment->chip == chip);
if (segments->read) {
/* Determine if this is the last segment of the transaction */
stop = (seg_count == 0) ? IC_DATA_CMD_STOP : 0;
/* Fill the FIFO with the necessary command bytes */
if (segment->read) {
/* Place read commands into the FIFO */
read_length = length;
while (length > 0) {
/* Send stop bit after last byte */
cmd = IC_DATA_CMD_READ;
if ((count == 0) && (length == 1))
cmd |= IC_DATA_CMD_STOP;
rx_buffer = segment->buf;
data_bytes = platform_i2c_read(restart, rx_buffer,
length, stop, &timeout);
/* Place read command in transmit FIFO */
regs->ic_data_cmd = cmd;
length--;
}
/* Return any detected error */
if (data_bytes < 0)
return data_bytes;
bytes_transferred += data_bytes;
} else {
/* Write the data into the FIFO */
while (length > 0) {
/* End of the transaction? */
cmd = IC_DATA_CMD_WRITE | *buffer++;
if ((count == 0) && (length == 1))
cmd |= IC_DATA_CMD_STOP;
tx_buffer = segment->buf;
tx_bytes += length;
data_bytes = platform_i2c_write(restart, tx_buffer,
length, stop, rx_buffer, &timeout);
/* Place a data byte into the FIFO */
regs->ic_data_cmd = cmd;
length--;
bytes_transferred++;
}
/* Return any detected error */
if (data_bytes < 0)
return data_bytes;
bytes_transferred += data_bytes;
}
segments++;
segment++;
restart = IC_DATA_CMD_RESTART;
}
/* Wait for the end of the transaction */
timeout = 1 * 1000 * 1000;
if (rx_buffer != NULL)
rx_buffer += bytes_transferred - tx_bytes;
do {
status = regs->ic_raw_intr_stat;
if (status & IC_INTR_STOP_DET)
break;
if ((status & (IC_INTR_RX_OVER | IC_INTR_RX_UNDER
| IC_INTR_TX_ABRT | IC_INTR_TX_OVER))
|| (timeout == 0)) {
if (timeout == 0)
printk (BIOS_ERR,
"ERROR - I2C stop bit not received!\n");
if (status & IC_INTR_RX_OVER)
printk (BIOS_ERR,
"ERROR - I2C receive overrun!\n");
if (status & IC_INTR_RX_UNDER)
printk (BIOS_ERR,
"ERROR - I2C receive underrun!\n");
if (status & IC_INTR_TX_ABRT)
printk (BIOS_ERR,
"ERROR - I2C transmit abort!\n");
if (status & IC_INTR_TX_OVER)
printk (BIOS_ERR,
"ERROR - I2C transmit overrun!\n");
i2c_disable(regs);
return -1;
/* Receive any available data */
status = regs->ic_status;
if ((rx_buffer != NULL) && (status & IC_STATUS_RFNE)) {
*rx_buffer++ = (uint8_t)regs->ic_data_cmd;
bytes_transferred++;
} else {
status = regs->ic_raw_intr_stat;
if ((total_bytes == bytes_transferred)
&& (status & IC_INTR_STOP_DET))
break;
/* Check for errors */
if (status & (IC_INTR_RX_OVER | IC_INTR_RX_UNDER
| IC_INTR_TX_ABRT | IC_INTR_TX_OVER)) {
i2c_disable(regs);
return -1;
}
/* Check for timeout */
if (stopwatch_expired(&timeout))
return -1;
/* Delay for a while */
udelay(1);
}
timeout--;
udelay(1);
} while (1);
i2c_disable(regs);
regs->ic_tar = 0;
/* Finish reading the data bytes */
while (read_length > 0) {
status = regs->ic_status;
*buffer++ = (uint8_t)regs->ic_data_cmd;
read_length--;
bytes_transferred++;
status = regs->ic_status;
}
/* Return the number of bytes transferred */
return bytes_transferred;
}