u-boot/drivers/i2c/ast2600_i2c.c
Ryan Chen 4088f5fce8 i2c:aspeed:support ast2600 i2c new register mode driver
Add i2c new register mode driver to support AST2600 i2c
new register mode. AST2600 i2c controller have legacy and
new register mode. The new register mode have global register
support 4 base clock for scl clock selection, and new clock
divider mode.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heiko Schocher <hs@denx.de>
2023-02-13 09:57:49 +01:00

366 lines
9 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright ASPEED Technology Inc.
*/
#include <common.h>
#include <clk.h>
#include <dm.h>
#include <errno.h>
#include <fdtdec.h>
#include <i2c.h>
#include <log.h>
#include <regmap.h>
#include <reset.h>
#include <asm/io.h>
#include <linux/iopoll.h>
#include "ast2600_i2c.h"
/* Device private data */
struct ast2600_i2c_priv {
struct clk clk;
struct ast2600_i2c_regs *regs;
void __iomem *global;
};
static int ast2600_i2c_read_data(struct ast2600_i2c_priv *priv, u8 chip_addr,
u8 *buffer, size_t len, bool send_stop)
{
int rx_cnt, ret = 0;
u32 cmd, isr;
for (rx_cnt = 0; rx_cnt < len; rx_cnt++, buffer++) {
cmd = I2CM_PKT_EN | I2CM_PKT_ADDR(chip_addr) |
I2CM_RX_CMD;
if (!rx_cnt)
cmd |= I2CM_START_CMD;
if ((len - 1) == rx_cnt)
cmd |= I2CM_RX_CMD_LAST;
if (send_stop && ((len - 1) == rx_cnt))
cmd |= I2CM_STOP_CMD;
writel(cmd, &priv->regs->cmd_sts);
ret = readl_poll_timeout(&priv->regs->isr, isr,
isr & I2CM_PKT_DONE,
I2C_TIMEOUT_US);
if (ret)
return -ETIMEDOUT;
*buffer =
I2CC_GET_RX_BUFF(readl(&priv->regs->trx_buff));
writel(I2CM_PKT_DONE, &priv->regs->isr);
if (isr & I2CM_TX_NAK)
return -EREMOTEIO;
}
return 0;
}
static int ast2600_i2c_write_data(struct ast2600_i2c_priv *priv, u8 chip_addr,
u8 *buffer, size_t len, bool send_stop)
{
int tx_cnt, ret = 0;
u32 cmd, isr;
if (!len) {
cmd = I2CM_PKT_EN | I2CM_PKT_ADDR(chip_addr) |
I2CM_START_CMD;
writel(cmd, &priv->regs->cmd_sts);
ret = readl_poll_timeout(&priv->regs->isr, isr,
isr & I2CM_PKT_DONE,
I2C_TIMEOUT_US);
if (ret)
return -ETIMEDOUT;
writel(I2CM_PKT_DONE, &priv->regs->isr);
if (isr & I2CM_TX_NAK)
return -EREMOTEIO;
}
for (tx_cnt = 0; tx_cnt < len; tx_cnt++, buffer++) {
cmd = I2CM_PKT_EN | I2CM_PKT_ADDR(chip_addr);
cmd |= I2CM_TX_CMD;
if (!tx_cnt)
cmd |= I2CM_START_CMD;
if (send_stop && ((len - 1) == tx_cnt))
cmd |= I2CM_STOP_CMD;
writel(*buffer, &priv->regs->trx_buff);
writel(cmd, &priv->regs->cmd_sts);
ret = readl_poll_timeout(&priv->regs->isr, isr,
isr & I2CM_PKT_DONE,
I2C_TIMEOUT_US);
if (ret)
return -ETIMEDOUT;
writel(I2CM_PKT_DONE, &priv->regs->isr);
if (isr & I2CM_TX_NAK)
return -EREMOTEIO;
}
return 0;
}
static int ast2600_i2c_deblock(struct udevice *dev)
{
struct ast2600_i2c_priv *priv = dev_get_priv(dev);
u32 csr = readl(&priv->regs->cmd_sts);
u32 isr;
int ret;
/* reinit */
writel(0, &priv->regs->fun_ctrl);
/* Enable Master Mode. Assuming single-master */
writel(I2CC_BUS_AUTO_RELEASE | I2CC_MASTER_EN |
I2CC_MULTI_MASTER_DIS,
&priv->regs->fun_ctrl);
csr = readl(&priv->regs->cmd_sts);
if (!(csr & I2CC_SDA_LINE_STS) &&
(csr & I2CC_SCL_LINE_STS)) {
debug("Bus stuck (%x), attempting recovery\n", csr);
writel(I2CM_RECOVER_CMD_EN, &priv->regs->cmd_sts);
ret = readl_poll_timeout(&priv->regs->isr, isr,
isr & (I2CM_BUS_RECOVER_FAIL |
I2CM_BUS_RECOVER),
I2C_TIMEOUT_US);
writel(~0, &priv->regs->isr);
if (ret)
return -EREMOTEIO;
}
return 0;
}
static int ast2600_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs)
{
struct ast2600_i2c_priv *priv = dev_get_priv(dev);
int ret;
if (readl(&priv->regs->trx_buff) & I2CC_BUS_BUSY_STS)
return -EREMOTEIO;
for (; nmsgs > 0; nmsgs--, msg++) {
if (msg->flags & I2C_M_RD) {
debug("i2c_read: chip=0x%x, len=0x%x, flags=0x%x\n",
msg->addr, msg->len, msg->flags);
ret = ast2600_i2c_read_data(priv, msg->addr, msg->buf,
msg->len, (nmsgs == 1));
} else {
debug("i2c_write: chip=0x%x, len=0x%x, flags=0x%x\n",
msg->addr, msg->len, msg->flags);
ret = ast2600_i2c_write_data(priv, msg->addr, msg->buf,
msg->len, (nmsgs == 1));
}
if (ret) {
debug("%s: error (%d)\n", __func__, ret);
return -EREMOTEIO;
}
}
return 0;
}
static int ast2600_i2c_set_speed(struct udevice *dev, unsigned int speed)
{
struct ast2600_i2c_priv *priv = dev_get_priv(dev);
unsigned long base_clk1, base_clk2, base_clk3, base_clk4;
int multiply = 10;
int baseclk_idx;
u32 clk_div_reg;
u32 apb_clk;
u32 scl_low;
u32 scl_high;
int divisor;
int inc = 0;
u32 data;
debug("Setting speed for I2C%d to <%u>\n", dev->seq_, speed);
if (!speed) {
debug("No valid speed specified\n");
return -EINVAL;
}
apb_clk = clk_get_rate(&priv->clk);
clk_div_reg = readl(priv->global + I2CG_CLK_DIV_CTRL);
base_clk1 = (apb_clk * multiply) / (((GET_CLK1_DIV(clk_div_reg) + 2) * multiply) / 2);
base_clk2 = (apb_clk * multiply) / (((GET_CLK2_DIV(clk_div_reg) + 2) * multiply) / 2);
base_clk3 = (apb_clk * multiply) / (((GET_CLK3_DIV(clk_div_reg) + 2) * multiply) / 2);
base_clk4 = (apb_clk * multiply) / (((GET_CLK4_DIV(clk_div_reg) + 2) * multiply) / 2);
if ((apb_clk / speed) <= 32) {
baseclk_idx = 0;
divisor = DIV_ROUND_UP(apb_clk, speed);
} else if ((base_clk1 / speed) <= 32) {
baseclk_idx = 1;
divisor = DIV_ROUND_UP(base_clk1, speed);
} else if ((base_clk2 / speed) <= 32) {
baseclk_idx = 2;
divisor = DIV_ROUND_UP(base_clk2, speed);
} else if ((base_clk3 / speed) <= 32) {
baseclk_idx = 3;
divisor = DIV_ROUND_UP(base_clk3, speed);
} else {
baseclk_idx = 4;
divisor = DIV_ROUND_UP(base_clk4, speed);
inc = 0;
while ((divisor + inc) > 32) {
inc |= divisor & 0x1;
divisor >>= 1;
baseclk_idx++;
}
divisor += inc;
}
divisor = min_t(int, divisor, 32);
baseclk_idx &= 0xf;
scl_low = ((divisor * 9) / 16) - 1;
scl_low = min_t(u32, scl_low, 0xf);
scl_high = (divisor - scl_low - 2) & 0xf;
/* Divisor : Base Clock : tCKHighMin : tCK High : tCK Low */
data = ((scl_high - 1) << 20) | (scl_high << 16) | (scl_low << 12) |
baseclk_idx;
/* Set AC Timing */
writel(data, &priv->regs->ac_timing);
return 0;
}
static int ast2600_i2c_probe(struct udevice *dev)
{
struct ast2600_i2c_priv *priv = dev_get_priv(dev);
ofnode i2c_global_node;
/* find global base address */
i2c_global_node = ofnode_get_parent(dev_ofnode(dev));
priv->global = (void *)ofnode_get_addr(i2c_global_node);
if (IS_ERR(priv->global)) {
debug("%s(): can't get global\n", __func__);
return PTR_ERR(priv->global);
}
/* Reset device */
writel(0, &priv->regs->fun_ctrl);
/* Enable Master Mode. Assuming single-master */
writel(I2CC_BUS_AUTO_RELEASE | I2CC_MASTER_EN |
I2CC_MULTI_MASTER_DIS,
&priv->regs->fun_ctrl);
writel(0, &priv->regs->ier);
/* Clear Interrupt */
writel(~0, &priv->regs->isr);
return 0;
}
static int ast2600_i2c_of_to_plat(struct udevice *dev)
{
struct ast2600_i2c_priv *priv = dev_get_priv(dev);
int ret;
priv->regs = dev_read_addr_ptr(dev);
if (!priv->regs)
return -EINVAL;
ret = clk_get_by_index(dev, 0, &priv->clk);
if (ret < 0) {
debug("%s: Can't get clock for %s: %d\n", __func__, dev->name,
ret);
return ret;
}
return 0;
}
static const struct dm_i2c_ops ast2600_i2c_ops = {
.xfer = ast2600_i2c_xfer,
.deblock = ast2600_i2c_deblock,
.set_bus_speed = ast2600_i2c_set_speed,
};
static const struct udevice_id ast2600_i2c_ids[] = {
{ .compatible = "aspeed,ast2600-i2c" },
{},
};
U_BOOT_DRIVER(ast2600_i2c) = {
.name = "ast2600_i2c",
.id = UCLASS_I2C,
.of_match = ast2600_i2c_ids,
.probe = ast2600_i2c_probe,
.of_to_plat = ast2600_i2c_of_to_plat,
.priv_auto = sizeof(struct ast2600_i2c_priv),
.ops = &ast2600_i2c_ops,
};
struct ast2600_i2c_global_priv {
void __iomem *regs;
struct reset_ctl reset;
};
/*
* APB clk : 100Mhz
* div : scl : baseclk [APB/((div/2) + 1)] : tBuf [1/bclk * 16]
* I2CG10[31:24] base clk4 for i2c auto recovery timeout counter (0xC6)
* I2CG10[23:16] base clk3 for Standard-mode (100Khz) min tBuf 4.7us
* 0x3c : 100.8Khz : 3.225Mhz : 4.96us
* 0x3d : 99.2Khz : 3.174Mhz : 5.04us
* 0x3e : 97.65Khz : 3.125Mhz : 5.12us
* 0x40 : 97.75Khz : 3.03Mhz : 5.28us
* 0x41 : 99.5Khz : 2.98Mhz : 5.36us (default)
* I2CG10[15:8] base clk2 for Fast-mode (400Khz) min tBuf 1.3us
* 0x12 : 400Khz : 10Mhz : 1.6us
* I2CG10[7:0] base clk1 for Fast-mode Plus (1Mhz) min tBuf 0.5us
* 0x08 : 1Mhz : 20Mhz : 0.8us
*/
static int aspeed_i2c_global_probe(struct udevice *dev)
{
struct ast2600_i2c_global_priv *i2c_global = dev_get_priv(dev);
void __iomem *regs;
int ret = 0;
i2c_global->regs = dev_read_addr_ptr(dev);
if (!i2c_global->regs)
return -EINVAL;
debug("%s(dev=%p)\n", __func__, dev);
regs = i2c_global->regs;
ret = reset_get_by_index(dev, 0, &i2c_global->reset);
if (ret) {
printf("%s(): Failed to get reset signal\n", __func__);
return ret;
}
reset_deassert(&i2c_global->reset);
writel(GLOBAL_INIT, regs + I2CG_CTRL);
writel(I2CCG_DIV_CTRL, regs + I2CG_CLK_DIV_CTRL);
return 0;
}
static const struct udevice_id aspeed_i2c_global_ids[] = {
{ .compatible = "aspeed,ast2600-i2c-global", },
{ }
};
U_BOOT_DRIVER(aspeed_i2c_global) = {
.name = "aspeed_i2c_global",
.id = UCLASS_MISC,
.of_match = aspeed_i2c_global_ids,
.probe = aspeed_i2c_global_probe,
.priv_auto = sizeof(struct ast2600_i2c_global_priv),
};