u-boot/drivers/i2c/tegra_i2c.c
Simon Glass cdce889959 tegra: Avoid using I2C prior to relocation
Tegra recently moved to the new I2C framework, which sets up I2C prior to
relocation, and prior to calling i2c_init_board(). This causes a crash on
Tegra boards.

Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
2013-08-13 17:11:25 -04:00

631 lines
15 KiB
C

/*
* Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
* Copyright (c) 2010-2011 NVIDIA Corporation
* NVIDIA Corporation <www.nvidia.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <fdtdec.h>
#include <i2c.h>
#include <asm/io.h>
#include <asm/arch/clock.h>
#include <asm/arch/funcmux.h>
#include <asm/arch/gpio.h>
#include <asm/arch/pinmux.h>
#include <asm/arch-tegra/clk_rst.h>
#include <asm/arch-tegra/tegra_i2c.h>
DECLARE_GLOBAL_DATA_PTR;
/* Information about i2c controller */
struct i2c_bus {
int id;
enum periph_id periph_id;
int speed;
int pinmux_config;
struct i2c_control *control;
struct i2c_ctlr *regs;
int is_dvc; /* DVC type, rather than I2C */
int is_scs; /* single clock source (T114+) */
int inited; /* bus is inited */
};
static struct i2c_bus i2c_controllers[TEGRA_I2C_NUM_CONTROLLERS];
static void set_packet_mode(struct i2c_bus *i2c_bus)
{
u32 config;
config = I2C_CNFG_NEW_MASTER_FSM_MASK | I2C_CNFG_PACKET_MODE_MASK;
if (i2c_bus->is_dvc) {
struct dvc_ctlr *dvc = (struct dvc_ctlr *)i2c_bus->regs;
writel(config, &dvc->cnfg);
} else {
writel(config, &i2c_bus->regs->cnfg);
/*
* program I2C_SL_CNFG.NEWSL to ENABLE. This fixes probe
* issues, i.e., some slaves may be wrongly detected.
*/
setbits_le32(&i2c_bus->regs->sl_cnfg, I2C_SL_CNFG_NEWSL_MASK);
}
}
static void i2c_reset_controller(struct i2c_bus *i2c_bus)
{
/* Reset I2C controller. */
reset_periph(i2c_bus->periph_id, 1);
/* re-program config register to packet mode */
set_packet_mode(i2c_bus);
}
static void i2c_init_controller(struct i2c_bus *i2c_bus)
{
/*
* Use PLLP - DP-04508-001_v06 datasheet indicates a divisor of 8
* here, in section 23.3.1, but in fact we seem to need a factor of
* 16 to get the right frequency.
*/
clock_start_periph_pll(i2c_bus->periph_id, CLOCK_ID_PERIPH,
i2c_bus->speed * 2 * 8);
if (i2c_bus->is_scs) {
/*
* T114 I2C went to a single clock source for standard/fast and
* HS clock speeds. The new clock rate setting calculation is:
* SCL = CLK_SOURCE.I2C /
* (CLK_MULT_STD_FAST_MODE * (I2C_CLK_DIV_STD_FAST_MODE+1) *
* I2C FREQUENCY DIVISOR) as per the T114 TRM (sec 30.3.1).
*
* NOTE: We do this here, after the initial clock/pll start,
* because if we read the clk_div reg before the controller
* is running, we hang, and we need it for the new calc.
*/
int clk_div_stdfst_mode = readl(&i2c_bus->regs->clk_div) >> 16;
debug("%s: CLK_DIV_STD_FAST_MODE setting = %d\n", __func__,
clk_div_stdfst_mode);
clock_start_periph_pll(i2c_bus->periph_id, CLOCK_ID_PERIPH,
CLK_MULT_STD_FAST_MODE * (clk_div_stdfst_mode + 1) *
i2c_bus->speed * 2);
}
/* Reset I2C controller. */
i2c_reset_controller(i2c_bus);
/* Configure I2C controller. */
if (i2c_bus->is_dvc) { /* only for DVC I2C */
struct dvc_ctlr *dvc = (struct dvc_ctlr *)i2c_bus->regs;
setbits_le32(&dvc->ctrl3, DVC_CTRL_REG3_I2C_HW_SW_PROG_MASK);
}
funcmux_select(i2c_bus->periph_id, i2c_bus->pinmux_config);
}
static void send_packet_headers(
struct i2c_bus *i2c_bus,
struct i2c_trans_info *trans,
u32 packet_id)
{
u32 data;
/* prepare header1: Header size = 0 Protocol = I2C, pktType = 0 */
data = PROTOCOL_TYPE_I2C << PKT_HDR1_PROTOCOL_SHIFT;
data |= packet_id << PKT_HDR1_PKT_ID_SHIFT;
data |= i2c_bus->id << PKT_HDR1_CTLR_ID_SHIFT;
writel(data, &i2c_bus->control->tx_fifo);
debug("pkt header 1 sent (0x%x)\n", data);
/* prepare header2 */
data = (trans->num_bytes - 1) << PKT_HDR2_PAYLOAD_SIZE_SHIFT;
writel(data, &i2c_bus->control->tx_fifo);
debug("pkt header 2 sent (0x%x)\n", data);
/* prepare IO specific header: configure the slave address */
data = trans->address << PKT_HDR3_SLAVE_ADDR_SHIFT;
/* Enable Read if it is not a write transaction */
if (!(trans->flags & I2C_IS_WRITE))
data |= PKT_HDR3_READ_MODE_MASK;
/* Write I2C specific header */
writel(data, &i2c_bus->control->tx_fifo);
debug("pkt header 3 sent (0x%x)\n", data);
}
static int wait_for_tx_fifo_empty(struct i2c_control *control)
{
u32 count;
int timeout_us = I2C_TIMEOUT_USEC;
while (timeout_us >= 0) {
count = (readl(&control->fifo_status) & TX_FIFO_EMPTY_CNT_MASK)
>> TX_FIFO_EMPTY_CNT_SHIFT;
if (count == I2C_FIFO_DEPTH)
return 1;
udelay(10);
timeout_us -= 10;
}
return 0;
}
static int wait_for_rx_fifo_notempty(struct i2c_control *control)
{
u32 count;
int timeout_us = I2C_TIMEOUT_USEC;
while (timeout_us >= 0) {
count = (readl(&control->fifo_status) & TX_FIFO_FULL_CNT_MASK)
>> TX_FIFO_FULL_CNT_SHIFT;
if (count)
return 1;
udelay(10);
timeout_us -= 10;
}
return 0;
}
static int wait_for_transfer_complete(struct i2c_control *control)
{
int int_status;
int timeout_us = I2C_TIMEOUT_USEC;
while (timeout_us >= 0) {
int_status = readl(&control->int_status);
if (int_status & I2C_INT_NO_ACK_MASK)
return -int_status;
if (int_status & I2C_INT_ARBITRATION_LOST_MASK)
return -int_status;
if (int_status & I2C_INT_XFER_COMPLETE_MASK)
return 0;
udelay(10);
timeout_us -= 10;
}
return -1;
}
static int send_recv_packets(struct i2c_bus *i2c_bus,
struct i2c_trans_info *trans)
{
struct i2c_control *control = i2c_bus->control;
u32 int_status;
u32 words;
u8 *dptr;
u32 local;
uchar last_bytes;
int error = 0;
int is_write = trans->flags & I2C_IS_WRITE;
/* clear status from previous transaction, XFER_COMPLETE, NOACK, etc. */
int_status = readl(&control->int_status);
writel(int_status, &control->int_status);
send_packet_headers(i2c_bus, trans, 1);
words = DIV_ROUND_UP(trans->num_bytes, 4);
last_bytes = trans->num_bytes & 3;
dptr = trans->buf;
while (words) {
u32 *wptr = (u32 *)dptr;
if (is_write) {
/* deal with word alignment */
if ((unsigned)dptr & 3) {
memcpy(&local, dptr, sizeof(u32));
writel(local, &control->tx_fifo);
debug("pkt data sent (0x%x)\n", local);
} else {
writel(*wptr, &control->tx_fifo);
debug("pkt data sent (0x%x)\n", *wptr);
}
if (!wait_for_tx_fifo_empty(control)) {
error = -1;
goto exit;
}
} else {
if (!wait_for_rx_fifo_notempty(control)) {
error = -1;
goto exit;
}
/*
* for the last word, we read into our local buffer,
* in case that caller did not provide enough buffer.
*/
local = readl(&control->rx_fifo);
if ((words == 1) && last_bytes)
memcpy(dptr, (char *)&local, last_bytes);
else if ((unsigned)dptr & 3)
memcpy(dptr, &local, sizeof(u32));
else
*wptr = local;
debug("pkt data received (0x%x)\n", local);
}
words--;
dptr += sizeof(u32);
}
if (wait_for_transfer_complete(control)) {
error = -1;
goto exit;
}
return 0;
exit:
/* error, reset the controller. */
i2c_reset_controller(i2c_bus);
return error;
}
static int tegra_i2c_write_data(struct i2c_bus *bus, u32 addr, u8 *data,
u32 len)
{
int error;
struct i2c_trans_info trans_info;
trans_info.address = addr;
trans_info.buf = data;
trans_info.flags = I2C_IS_WRITE;
trans_info.num_bytes = len;
trans_info.is_10bit_address = 0;
error = send_recv_packets(bus, &trans_info);
if (error)
debug("tegra_i2c_write_data: Error (%d) !!!\n", error);
return error;
}
static int tegra_i2c_read_data(struct i2c_bus *bus, u32 addr, u8 *data,
u32 len)
{
int error;
struct i2c_trans_info trans_info;
trans_info.address = addr | 1;
trans_info.buf = data;
trans_info.flags = 0;
trans_info.num_bytes = len;
trans_info.is_10bit_address = 0;
error = send_recv_packets(bus, &trans_info);
if (error)
debug("tegra_i2c_read_data: Error (%d) !!!\n", error);
return error;
}
#ifndef CONFIG_OF_CONTROL
#error "Please enable device tree support to use this driver"
#endif
/**
* Check that a bus number is valid and return a pointer to it
*
* @param bus_num Bus number to check / return
* @return pointer to bus, if valid, else NULL
*/
static struct i2c_bus *tegra_i2c_get_bus(struct i2c_adapter *adap)
{
struct i2c_bus *bus;
bus = &i2c_controllers[adap->hwadapnr];
if (!bus->inited) {
debug("%s: Bus %u not available\n", __func__, adap->hwadapnr);
return NULL;
}
return bus;
}
static unsigned int tegra_i2c_set_bus_speed(struct i2c_adapter *adap,
unsigned int speed)
{
struct i2c_bus *bus;
bus = tegra_i2c_get_bus(adap);
if (!bus)
return 0;
bus->speed = speed;
i2c_init_controller(bus);
return 0;
}
static int i2c_get_config(const void *blob, int node, struct i2c_bus *i2c_bus)
{
i2c_bus->regs = (struct i2c_ctlr *)fdtdec_get_addr(blob, node, "reg");
/*
* We don't have a binding for pinmux yet. Leave it out for now. So
* far no one needs anything other than the default.
*/
i2c_bus->pinmux_config = FUNCMUX_DEFAULT;
i2c_bus->speed = fdtdec_get_int(blob, node, "clock-frequency", 0);
i2c_bus->periph_id = clock_decode_periph_id(blob, node);
/*
* We can't specify the pinmux config in the fdt, so I2C2 will not
* work on Seaboard. It normally has no devices on it anyway.
* You could add in this little hack if you need to use it.
* The correct solution is a pinmux binding in the fdt.
*
* if (i2c_bus->periph_id == PERIPH_ID_I2C2)
* i2c_bus->pinmux_config = FUNCMUX_I2C2_PTA;
*/
if (i2c_bus->periph_id == -1)
return -FDT_ERR_NOTFOUND;
return 0;
}
/*
* Process a list of nodes, adding them to our list of I2C ports.
*
* @param blob fdt blob
* @param node_list list of nodes to process (any <=0 are ignored)
* @param count number of nodes to process
* @param is_dvc 1 if these are DVC ports, 0 if standard I2C
* @param is_scs 1 if this HW uses a single clock source (T114+)
* @return 0 if ok, -1 on error
*/
static int process_nodes(const void *blob, int node_list[], int count,
int is_dvc, int is_scs)
{
struct i2c_bus *i2c_bus;
int i;
/* build the i2c_controllers[] for each controller */
for (i = 0; i < count; i++) {
int node = node_list[i];
if (node <= 0)
continue;
i2c_bus = &i2c_controllers[i];
i2c_bus->id = i;
if (i2c_get_config(blob, node, i2c_bus)) {
printf("i2c_init_board: failed to decode bus %d\n", i);
return -1;
}
i2c_bus->is_scs = is_scs;
i2c_bus->is_dvc = is_dvc;
if (is_dvc) {
i2c_bus->control =
&((struct dvc_ctlr *)i2c_bus->regs)->control;
} else {
i2c_bus->control = &i2c_bus->regs->control;
}
debug("%s: controller bus %d at %p, periph_id %d, speed %d: ",
is_dvc ? "dvc" : "i2c", i, i2c_bus->regs,
i2c_bus->periph_id, i2c_bus->speed);
i2c_init_controller(i2c_bus);
debug("ok\n");
i2c_bus->inited = 1;
/* Mark position as used */
node_list[i] = -1;
}
return 0;
}
/* Sadly there is no error return from this function */
void i2c_init_board(void)
{
int node_list[TEGRA_I2C_NUM_CONTROLLERS];
const void *blob = gd->fdt_blob;
int count;
/* First check for newer (T114+) I2C ports */
count = fdtdec_find_aliases_for_id(blob, "i2c",
COMPAT_NVIDIA_TEGRA114_I2C, node_list,
TEGRA_I2C_NUM_CONTROLLERS);
if (process_nodes(blob, node_list, count, 0, 1))
return;
/* Now get the older (T20/T30) normal I2C ports */
count = fdtdec_find_aliases_for_id(blob, "i2c",
COMPAT_NVIDIA_TEGRA20_I2C, node_list,
TEGRA_I2C_NUM_CONTROLLERS);
if (process_nodes(blob, node_list, count, 0, 0))
return;
/* Now look for dvc ports */
count = fdtdec_add_aliases_for_id(blob, "i2c",
COMPAT_NVIDIA_TEGRA20_DVC, node_list,
TEGRA_I2C_NUM_CONTROLLERS);
if (process_nodes(blob, node_list, count, 1, 0))
return;
}
static void tegra_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
{
/* No i2c support prior to relocation */
if (!(gd->flags & GD_FLG_RELOC))
return;
/* This will override the speed selected in the fdt for that port */
debug("i2c_init(speed=%u, slaveaddr=0x%x)\n", speed, slaveaddr);
i2c_set_bus_speed(speed);
}
/* i2c write version without the register address */
int i2c_write_data(struct i2c_bus *bus, uchar chip, uchar *buffer, int len)
{
int rc;
debug("i2c_write_data: chip=0x%x, len=0x%x\n", chip, len);
debug("write_data: ");
/* use rc for counter */
for (rc = 0; rc < len; ++rc)
debug(" 0x%02x", buffer[rc]);
debug("\n");
/* Shift 7-bit address over for lower-level i2c functions */
rc = tegra_i2c_write_data(bus, chip << 1, buffer, len);
if (rc)
debug("i2c_write_data(): rc=%d\n", rc);
return rc;
}
/* i2c read version without the register address */
int i2c_read_data(struct i2c_bus *bus, uchar chip, uchar *buffer, int len)
{
int rc;
debug("inside i2c_read_data():\n");
/* Shift 7-bit address over for lower-level i2c functions */
rc = tegra_i2c_read_data(bus, chip << 1, buffer, len);
if (rc) {
debug("i2c_read_data(): rc=%d\n", rc);
return rc;
}
debug("i2c_read_data: ");
/* reuse rc for counter*/
for (rc = 0; rc < len; ++rc)
debug(" 0x%02x", buffer[rc]);
debug("\n");
return 0;
}
/* Probe to see if a chip is present. */
static int tegra_i2c_probe(struct i2c_adapter *adap, uchar chip)
{
struct i2c_bus *bus;
int rc;
uchar reg;
debug("i2c_probe: addr=0x%x\n", chip);
bus = tegra_i2c_get_bus(adap);
if (!bus)
return 1;
reg = 0;
rc = i2c_write_data(bus, chip, &reg, 1);
if (rc) {
debug("Error probing 0x%x.\n", chip);
return 1;
}
return 0;
}
static int i2c_addr_ok(const uint addr, const int alen)
{
/* We support 7 or 10 bit addresses, so one or two bytes each */
return alen == 1 || alen == 2;
}
/* Read bytes */
static int tegra_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
int alen, uchar *buffer, int len)
{
struct i2c_bus *bus;
uint offset;
int i;
debug("i2c_read: chip=0x%x, addr=0x%x, len=0x%x\n",
chip, addr, len);
bus = tegra_i2c_get_bus(adap);
if (!bus)
return 1;
if (!i2c_addr_ok(addr, alen)) {
debug("i2c_read: Bad address %x.%d.\n", addr, alen);
return 1;
}
for (offset = 0; offset < len; offset++) {
if (alen) {
uchar data[alen];
for (i = 0; i < alen; i++) {
data[alen - i - 1] =
(addr + offset) >> (8 * i);
}
if (i2c_write_data(bus, chip, data, alen)) {
debug("i2c_read: error sending (0x%x)\n",
addr);
return 1;
}
}
if (i2c_read_data(bus, chip, buffer + offset, 1)) {
debug("i2c_read: error reading (0x%x)\n", addr);
return 1;
}
}
return 0;
}
/* Write bytes */
static int tegra_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
int alen, uchar *buffer, int len)
{
struct i2c_bus *bus;
uint offset;
int i;
debug("i2c_write: chip=0x%x, addr=0x%x, len=0x%x\n",
chip, addr, len);
bus = tegra_i2c_get_bus(adap);
if (!bus)
return 1;
if (!i2c_addr_ok(addr, alen)) {
debug("i2c_write: Bad address %x.%d.\n", addr, alen);
return 1;
}
for (offset = 0; offset < len; offset++) {
uchar data[alen + 1];
for (i = 0; i < alen; i++)
data[alen - i - 1] = (addr + offset) >> (8 * i);
data[alen] = buffer[offset];
if (i2c_write_data(bus, chip, data, alen + 1)) {
debug("i2c_write: error sending (0x%x)\n", addr);
return 1;
}
}
return 0;
}
int tegra_i2c_get_dvc_bus_num(void)
{
int i;
for (i = 0; i < TEGRA_I2C_NUM_CONTROLLERS; i++) {
struct i2c_bus *bus = &i2c_controllers[i];
if (bus->inited && bus->is_dvc)
return i;
}
return -1;
}
/*
* Register soft i2c adapters
*/
U_BOOT_I2C_ADAP_COMPLETE(tegra0, tegra_i2c_init, tegra_i2c_probe,
tegra_i2c_read, tegra_i2c_write,
tegra_i2c_set_bus_speed, 100000, 0, 0)
U_BOOT_I2C_ADAP_COMPLETE(tegra1, tegra_i2c_init, tegra_i2c_probe,
tegra_i2c_read, tegra_i2c_write,
tegra_i2c_set_bus_speed, 100000, 0, 1)
U_BOOT_I2C_ADAP_COMPLETE(tegra2, tegra_i2c_init, tegra_i2c_probe,
tegra_i2c_read, tegra_i2c_write,
tegra_i2c_set_bus_speed, 100000, 0, 2)
U_BOOT_I2C_ADAP_COMPLETE(tegra3, tegra_i2c_init, tegra_i2c_probe,
tegra_i2c_read, tegra_i2c_write,
tegra_i2c_set_bus_speed, 100000, 0, 3)