[PATCH v3 1/2] i2c:aspeed:support ast2600 i2c new register mode driver

Ryan Chen
2023-01-30T06:20:19Z

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>
---
MAINTAINERS | 6 +
drivers/i2c/Kconfig | 10 ++
drivers/i2c/Makefile | 1 +
drivers/i2c/ast2600_i2c.c | 367 ++++++++++++++++++++++++++++++++++++++
drivers/i2c/ast2600_i2c.h | 120 +++++++++++++
5 files changed, 504 insertions(+)
create mode 100644 drivers/i2c/ast2600_i2c.c
create mode 100644 drivers/i2c/ast2600_i2c.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 3fc4cd0f12..1cf54f0b4e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -769,6 +769,12 @@ S: Maintained
F: drivers/pci/pcie_phytium.c
F: arch/arm/dts/phytium-durian.dts

+ASPEED AST2600 I2C DRIVER
+M: Ryan Chen <ryan_chen@aspeedtech.com>
+R: Aspeed BMC SW team <BMC-SW@aspeedtech.com>
+S: Maintained
+F: drivers/i2c/ast2600_i2c.c
+
ASPEED FMC SPI DRIVER
M: Chin-Ting Kuo <chin-ting_kuo@aspeedtech.com>
M: Cédric Le Goater <clg@kaod.org>
diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
index 08b6c7bdcc..77e2a1c4c0 100644
--- a/drivers/i2c/Kconfig
+++ b/drivers/i2c/Kconfig
@@ -221,6 +221,16 @@ config SYS_I2C_DW
controller is used in various SoCs, e.g. the ST SPEAr, Altera
SoCFPGA, Synopsys ARC700 and some Intel x86 SoCs.

+config SYS_I2C_AST2600
+ bool "AST2600 I2C Controller"
+ depends on DM_I2C && ARCH_ASPEED
+ help
+ Say yes here to select AST2600 I2C Host Controller. The driver
+ support AST2600 I2C new mode register. This I2C controller supports:
+ _Standard-mode (up to 100 kHz)
+ _Fast-mode (up to 400 kHz)
+ _Fast-mode Plus (up to 1 MHz)
+
config SYS_I2C_ASPEED
bool "Aspeed I2C Controller"
depends on DM_I2C && ARCH_ASPEED
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index 920aafb91c..89db2d8e37 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_$(SPL_)I2C_CROS_EC_LDO) += cros_ec_ldo.o

obj-$(CONFIG_$(SPL_)SYS_I2C_LEGACY) += i2c_core.o
obj-$(CONFIG_SYS_I2C_ASPEED) += ast_i2c.o
+obj-$(CONFIG_SYS_I2C_AST2600) += ast2600_i2c.o
obj-$(CONFIG_SYS_I2C_AT91) += at91_i2c.o
obj-$(CONFIG_SYS_I2C_CADENCE) += i2c-cdns.o
obj-$(CONFIG_SYS_I2C_CA) += i2c-cortina.o
diff --git a/drivers/i2c/ast2600_i2c.c b/drivers/i2c/ast2600_i2c.c
new file mode 100644
index 0000000000..f9d9ff09b3
--- /dev/null
+++ b/drivers/i2c/ast2600_i2c.c
@@ -0,0 +1,367 @@
+// 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),
+};
+
diff --git a/drivers/i2c/ast2600_i2c.h b/drivers/i2c/ast2600_i2c.h
new file mode 100644
index 0000000000..69699ba84c
--- /dev/null
+++ b/drivers/i2c/ast2600_i2c.h
@@ -0,0 +1,120 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright ASPEED Technology Inc.
+ */
+#ifndef __AST2600_I2C_H_
+#define __AST2600_I2C_H_
+
+struct ast2600_i2c_regs {
+ u32 fun_ctrl;
+ u32 ac_timing;
+ u32 trx_buff;
+ u32 icr;
+ u32 ier;
+ u32 isr;
+ u32 cmd_sts;
+};
+
+/* 0x00 : I2CC Master/Slave Function Control Register */
+#define I2CC_SLAVE_ADDR_RX_EN BIT(20)
+#define I2CC_MASTER_RETRY_MASK GENMASK(19, 18)
+#define I2CC_MASTER_RETRY(x) (((x) & GENMASK(1, 0)) << 18)
+#define I2CC_BUS_AUTO_RELEASE BIT(17)
+#define I2CC_M_SDA_LOCK_EN BIT(16)
+#define I2CC_MULTI_MASTER_DIS BIT(15)
+#define I2CC_M_SCL_DRIVE_EN BIT(14)
+#define I2CC_MSB_STS BIT(9)
+#define I2CC_SDA_DRIVE_1T_EN BIT(8)
+#define I2CC_M_SDA_DRIVE_1T_EN BIT(7)
+#define I2CC_M_HIGH_SPEED_EN BIT(6)
+/* reserved 5 : 2 */
+#define I2CC_SLAVE_EN BIT(1)
+#define I2CC_MASTER_EN BIT(0)
+
+/* 0x04 : I2CD Clock and AC Timing Control Register #1 */
+/* Base register value. These bits are always set by the driver. */
+#define I2CD_CACTC_BASE 0xfff00300
+#define I2CD_TCKHIGH_SHIFT 16
+#define I2CD_TCKLOW_SHIFT 12
+#define I2CD_THDDAT_SHIFT 10
+#define I2CD_TO_DIV_SHIFT 8
+#define I2CD_BASE_DIV_SHIFT 0
+
+/* 0x08 : I2CC Master/Slave Transmit/Receive Byte Buffer Register */
+#define I2CC_TX_DIR_MASK GENMASK(31, 29)
+#define I2CC_SDA_OE BIT(28)
+#define I2CC_SDA_O BIT(27)
+#define I2CC_SCL_OE BIT(26)
+#define I2CC_SCL_O BIT(25)
+
+#define I2CC_SCL_LINE_STS BIT(18)
+#define I2CC_SDA_LINE_STS BIT(17)
+#define I2CC_BUS_BUSY_STS BIT(16)
+#define I2CC_GET_RX_BUFF(x) (((x) >> 8) & GENMASK(7, 0))
+
+/* 0x10 : I2CM Master Interrupt Control Register */
+/* 0x14 : I2CM Master Interrupt Status Register */
+#define I2CM_PKT_TIMEOUT BIT(18)
+#define I2CM_PKT_ERROR BIT(17)
+#define I2CM_PKT_DONE BIT(16)
+
+#define I2CM_BUS_RECOVER_FAIL BIT(15)
+#define I2CM_SDA_DL_TO BIT(14)
+#define I2CM_BUS_RECOVER BIT(13)
+#define I2CM_SMBUS_ALT BIT(12)
+
+#define I2CM_SCL_LOW_TO BIT(6)
+#define I2CM_ABNORMAL BIT(5)
+#define I2CM_NORMAL_STOP BIT(4)
+#define I2CM_ARBIT_LOSS BIT(3)
+#define I2CM_RX_DONE BIT(2)
+#define I2CM_TX_NAK BIT(1)
+#define I2CM_TX_ACK BIT(0)
+
+/* 0x18 : I2CM Master Command/Status Register */
+#define I2CM_PKT_ADDR(x) (((x) & GENMASK(6, 0)) << 24)
+#define I2CM_PKT_EN BIT(16)
+#define I2CM_SDA_OE_OUT_DIR BIT(15)
+#define I2CM_SDA_O_OUT_DIR BIT(14)
+#define I2CM_SCL_OE_OUT_DIR BIT(13)
+#define I2CM_SCL_O_OUT_DIR BIT(12)
+#define I2CM_RECOVER_CMD_EN BIT(11)
+
+#define I2CM_RX_DMA_EN BIT(9)
+#define I2CM_TX_DMA_EN BIT(8)
+/* Command Bit */
+#define I2CM_RX_BUFF_EN BIT(7)
+#define I2CM_TX_BUFF_EN BIT(6)
+#define I2CM_STOP_CMD BIT(5)
+#define I2CM_RX_CMD_LAST BIT(4)
+#define I2CM_RX_CMD BIT(3)
+
+#define I2CM_TX_CMD BIT(1)
+#define I2CM_START_CMD BIT(0)
+
+#define I2C_TIMEOUT_US 100000
+
+/* I2C Global Register */
+#define I2CG_ISR 0x00
+#define I2CG_SLAVE_ISR 0x04
+#define I2CG_OWNER 0x08
+#define I2CG_CTRL 0x0C
+#define I2CG_CLK_DIV_CTRL 0x10
+
+#define I2CG_SLAVE_PKT_NAK BIT(4)
+#define I2CG_M_S_SEPARATE_INTR BIT(3)
+#define I2CG_CTRL_NEW_REG BIT(2)
+#define I2CG_CTRL_NEW_CLK_DIV BIT(1)
+
+#define GLOBAL_INIT \
+ (I2CG_SLAVE_PKT_NAK | \
+ I2CG_CTRL_NEW_REG | \
+ I2CG_CTRL_NEW_CLK_DIV)
+#define I2CCG_DIV_CTRL 0xc6411208
+
+#define GET_CLK1_DIV(x) ((x) & 0xff)
+#define GET_CLK2_DIV(x) (((x) >> 8) & 0xff)
+#define GET_CLK3_DIV(x) (((x) >> 16) & 0xff)
+#define GET_CLK4_DIV(x) (((x) >> 24) & 0xff)
+
+#endif /* __AST2600_I2C_H_ */
--
2.34.1