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i2c: i2c-cortina: added CAxxxx I2C support

Add I2C controller support for Cortina Access CAxxxx SoCs

Signed-off-by: Arthur Li <arthur.li@cortina-access.com>
Signed-off-by: Alex Nemirovsky <alex.nemirovsky@cortina-access.com>
CC: Heiko Schocher <hs@denx.de>
Reviewed-by: Heiko Schocher <hs@denx.de>

hs: fixed build error, add include log.h
Arthur Li 4 anni fa
parent
commit
7f5ea25062

+ 4 - 0
MAINTAINERS

@@ -182,6 +182,8 @@ F:	drivers/gpio/cortina_gpio.c
 F:	drivers/watchdog/cortina_wdt.c
 F:	drivers/watchdog/cortina_wdt.c
 F:	drivers/serial/serial_cortina.c
 F:	drivers/serial/serial_cortina.c
 F:	drivers/mmc/ca_dw_mmc.c
 F:	drivers/mmc/ca_dw_mmc.c
+F:	drivers/i2c/i2c-cortina.c
+F:	drivers/i2c/i2c-cortina.h
 
 
 ARM/CZ.NIC TURRIS MOX SUPPORT
 ARM/CZ.NIC TURRIS MOX SUPPORT
 M:	Marek Behun <marek.behun@nic.cz>
 M:	Marek Behun <marek.behun@nic.cz>
@@ -740,6 +742,8 @@ F:	drivers/gpio/cortina_gpio.c
 F:	drivers/watchdog/cortina_wdt.c
 F:	drivers/watchdog/cortina_wdt.c
 F:	drivers/serial/serial_cortina.c
 F:	drivers/serial/serial_cortina.c
 F:	drivers/mmc/ca_dw_mmc.c
 F:	drivers/mmc/ca_dw_mmc.c
+F:	drivers/i2c/i2c-cortina.c
+F:	drivers/i2c/i2c-cortina.h
 
 
 MIPS MSCC
 MIPS MSCC
 M:	Gregory CLEMENT <gregory.clement@bootlin.com>
 M:	Gregory CLEMENT <gregory.clement@bootlin.com>

+ 18 - 0
doc/device-tree-bindings/i2c/i2c-cortina.txt

@@ -0,0 +1,18 @@
+* I2C for Cortina platforms
+
+Required properties :
+- compatible : Must be "cortina,ca-i2c"
+- reg : Offset and length of the register set for the device
+
+Recommended properties :
+- clock-frequency : desired I2C bus clock frequency in Hz. If not specified,
+		    default value is 100000. Possible values are 100000,
+		    400000 and 1000000.
+
+Examples :
+
+	i2c: i2c@f4329120 {
+		compatible = "cortina,ca-i2c";
+		reg = <0x0 0xf4329120 0x28>;
+		clock-frequency = <400000>;
+	};

+ 8 - 0
drivers/i2c/Kconfig

@@ -93,6 +93,14 @@ config SYS_I2C_CADENCE
 	  Say yes here to select Cadence I2C Host Controller. This controller is
 	  Say yes here to select Cadence I2C Host Controller. This controller is
 	  e.g. used by Xilinx Zynq.
 	  e.g. used by Xilinx Zynq.
 
 
+config SYS_I2C_CA
+	tristate "Cortina-Access I2C Controller"
+	depends on DM_I2C && CORTINA_PLATFORM
+	default n
+	help
+	  Add support for the Cortina Access I2C host controller.
+	  Say yes here to select Cortina-Access I2C Host Controller.
+
 config SYS_I2C_DAVINCI
 config SYS_I2C_DAVINCI
 	bool "Davinci I2C Controller"
 	bool "Davinci I2C Controller"
 	depends on (ARCH_KEYSTONE || ARCH_DAVINCI)
 	depends on (ARCH_KEYSTONE || ARCH_DAVINCI)

+ 1 - 0
drivers/i2c/Makefile

@@ -12,6 +12,7 @@ obj-$(CONFIG_SYS_I2C) += i2c_core.o
 obj-$(CONFIG_SYS_I2C_ASPEED) += ast_i2c.o
 obj-$(CONFIG_SYS_I2C_ASPEED) += ast_i2c.o
 obj-$(CONFIG_SYS_I2C_AT91) += at91_i2c.o
 obj-$(CONFIG_SYS_I2C_AT91) += at91_i2c.o
 obj-$(CONFIG_SYS_I2C_CADENCE) += i2c-cdns.o
 obj-$(CONFIG_SYS_I2C_CADENCE) += i2c-cdns.o
+obj-$(CONFIG_SYS_I2C_CA) += i2c-cortina.o
 obj-$(CONFIG_SYS_I2C_DAVINCI) += davinci_i2c.o
 obj-$(CONFIG_SYS_I2C_DAVINCI) += davinci_i2c.o
 obj-$(CONFIG_SYS_I2C_DW) += designware_i2c.o
 obj-$(CONFIG_SYS_I2C_DW) += designware_i2c.o
 ifdef CONFIG_DM_PCI
 ifdef CONFIG_DM_PCI

+ 347 - 0
drivers/i2c/i2c-cortina.c

@@ -0,0 +1,347 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2020
+ * Arthur Li, Cortina Access, arthur.li@cortina-access.com.
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <log.h>
+#include <asm/io.h>
+#include <dm.h>
+#include <mapmem.h>
+#include "i2c-cortina.h"
+
+static void set_speed(struct i2c_regs *regs, int i2c_spd)
+{
+	union ca_biw_cfg i2c_cfg;
+
+	i2c_cfg.wrd = readl(&regs->i2c_cfg);
+	i2c_cfg.bf.core_en = 0;
+	writel(i2c_cfg.wrd, &regs->i2c_cfg);
+
+	switch (i2c_spd) {
+	case IC_SPEED_MODE_FAST_PLUS:
+		i2c_cfg.bf.prer = CORTINA_PER_IO_FREQ /
+				  (5 * I2C_SPEED_FAST_PLUS_RATE) - 1;
+		break;
+
+	case IC_SPEED_MODE_STANDARD:
+		i2c_cfg.bf.prer = CORTINA_PER_IO_FREQ /
+				  (5 * I2C_SPEED_STANDARD_RATE) - 1;
+		break;
+
+	case IC_SPEED_MODE_FAST:
+	default:
+		i2c_cfg.bf.prer = CORTINA_PER_IO_FREQ /
+				  (5 * I2C_SPEED_FAST_RATE) - 1;
+		break;
+	}
+
+	i2c_cfg.bf.core_en = 1;
+	writel(i2c_cfg.wrd, &regs->i2c_cfg);
+}
+
+static int ca_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
+{
+	struct ca_i2c *priv = dev_get_priv(bus);
+	int i2c_spd;
+
+	if (speed >= I2C_SPEED_FAST_PLUS_RATE) {
+		i2c_spd = IC_SPEED_MODE_FAST_PLUS;
+		priv->speed = I2C_SPEED_FAST_PLUS_RATE;
+	} else if (speed >= I2C_SPEED_FAST_RATE) {
+		i2c_spd = IC_SPEED_MODE_FAST;
+		priv->speed = I2C_SPEED_FAST_RATE;
+	} else {
+		i2c_spd = IC_SPEED_MODE_STANDARD;
+		priv->speed = I2C_SPEED_STANDARD_RATE;
+	}
+
+	set_speed(priv->regs, i2c_spd);
+
+	return 0;
+}
+
+static int ca_i2c_get_bus_speed(struct udevice *bus)
+{
+	struct ca_i2c *priv = dev_get_priv(bus);
+
+	return priv->speed;
+}
+
+static void ca_i2c_init(struct i2c_regs *regs)
+{
+	union ca_biw_cfg i2c_cfg;
+
+	i2c_cfg.wrd = readl(&regs->i2c_cfg);
+	i2c_cfg.bf.core_en = 0;
+	i2c_cfg.bf.biw_soft_reset = 1;
+	writel(i2c_cfg.wrd, &regs->i2c_cfg);
+	mdelay(10);
+	i2c_cfg.bf.biw_soft_reset = 0;
+	writel(i2c_cfg.wrd, &regs->i2c_cfg);
+
+	set_speed(regs, IC_SPEED_MODE_STANDARD);
+
+	i2c_cfg.wrd = readl(&regs->i2c_cfg);
+	i2c_cfg.bf.core_en = 1;
+	writel(i2c_cfg.wrd, &regs->i2c_cfg);
+}
+
+static int i2c_wait_complete(struct i2c_regs *regs)
+{
+	union ca_biw_ctrl i2c_ctrl;
+	unsigned long start_time_bb = get_timer(0);
+
+	i2c_ctrl.wrd = readl(&regs->i2c_ctrl);
+
+	while (i2c_ctrl.bf.biwdone == 0) {
+		i2c_ctrl.wrd = readl(&regs->i2c_ctrl);
+
+		if (get_timer(start_time_bb) >
+		   (unsigned long)(I2C_BYTE_TO_BB)) {
+			printf("%s not done!!!\n", __func__);
+			return -ETIMEDOUT;
+		}
+	}
+
+	/* Clear done bit */
+	writel(i2c_ctrl.wrd, &regs->i2c_ctrl);
+
+	return 0;
+}
+
+static void i2c_setaddress(struct i2c_regs *regs, unsigned int i2c_addr,
+			   int write_read)
+{
+	writel(i2c_addr | write_read, &regs->i2c_txr);
+
+	writel(BIW_CTRL_START | BIW_CTRL_WRITE,
+	       &regs->i2c_ctrl);
+
+	i2c_wait_complete(regs);
+}
+
+static int i2c_wait_for_bus_busy(struct i2c_regs *regs)
+{
+	union ca_biw_ack i2c_ack;
+	unsigned long start_time_bb = get_timer(0);
+
+	i2c_ack.wrd = readl(&regs->i2c_ack);
+
+	while (i2c_ack.bf.biw_busy) {
+		i2c_ack.wrd = readl(&regs->i2c_ack);
+
+		if (get_timer(start_time_bb) >
+		   (unsigned long)(I2C_BYTE_TO_BB)) {
+			printf("%s: timeout!\n", __func__);
+			return -ETIMEDOUT;
+		}
+	}
+
+	return 0;
+}
+
+static int i2c_xfer_init(struct i2c_regs *regs, uint8_t chip, uint addr,
+			 int alen, int write_read)
+{
+	int addr_len = alen;
+
+	if (i2c_wait_for_bus_busy(regs))
+		return 1;
+
+	/* First cycle must write addr + offset */
+	chip = ((chip & 0x7F) << 1);
+	if (alen == 0 && write_read == I2C_CMD_RD)
+		i2c_setaddress(regs, chip, I2C_CMD_RD);
+	else
+		i2c_setaddress(regs, chip, I2C_CMD_WT);
+
+	while (alen) {
+		alen--;
+		writel(addr, &regs->i2c_txr);
+		if (write_read == I2C_CMD_RD)
+			writel(BIW_CTRL_WRITE | BIW_CTRL_STOP,
+			       &regs->i2c_ctrl);
+		else
+			writel(BIW_CTRL_WRITE, &regs->i2c_ctrl);
+		i2c_wait_complete(regs);
+	}
+
+	/* Send address again with Read flag if it's read command */
+	if (write_read == I2C_CMD_RD && addr_len > 0)
+		i2c_setaddress(regs, chip, I2C_CMD_RD);
+
+	return 0;
+}
+
+static int i2c_xfer_finish(struct i2c_regs *regs)
+{
+	/* Dummy read makes bus free */
+	writel(BIW_CTRL_READ | BIW_CTRL_STOP, &regs->i2c_ctrl);
+	i2c_wait_complete(regs);
+
+	if (i2c_wait_for_bus_busy(regs)) {
+		printf("Timed out waiting for bus\n");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static int ca_i2c_read(struct i2c_regs *regs, uint8_t chip, uint addr,
+		       int alen, uint8_t *buffer, int len)
+{
+	unsigned long start_time_rx;
+	int rc = 0;
+
+	rc = i2c_xfer_init(regs, chip, addr, alen, I2C_CMD_RD);
+	if (rc)
+		return rc;
+
+	start_time_rx = get_timer(0);
+	while (len) {
+		/* ACK_IN is ack value to send during read.
+		 * ack high only on the very last byte!
+		 */
+		if (len == 1)
+			writel(BIW_CTRL_READ | BIW_CTRL_ACK_IN | BIW_CTRL_STOP,
+			       &regs->i2c_ctrl);
+		else
+			writel(BIW_CTRL_READ, &regs->i2c_ctrl);
+
+		rc = i2c_wait_complete(regs);
+		udelay(1);
+
+		if (rc == 0) {
+			*buffer++ =
+				(uchar) readl(&regs->i2c_rxr);
+			len--;
+			start_time_rx = get_timer(0);
+
+		} else if (get_timer(start_time_rx) > I2C_BYTE_TO) {
+			return -ETIMEDOUT;
+		}
+	}
+	i2c_xfer_finish(regs);
+	return rc;
+}
+
+static int ca_i2c_write(struct i2c_regs *regs, uint8_t chip, uint addr,
+			int alen, uint8_t *buffer, int len)
+{
+	int rc, nb = len;
+	unsigned long start_time_tx;
+
+	rc = i2c_xfer_init(regs, chip, addr, alen, I2C_CMD_WT);
+	if (rc)
+		return rc;
+
+	start_time_tx = get_timer(0);
+	while (len) {
+		writel(*buffer, &regs->i2c_txr);
+		if (len == 1)
+			writel(BIW_CTRL_WRITE | BIW_CTRL_STOP,
+			       &regs->i2c_ctrl);
+		else
+			writel(BIW_CTRL_WRITE, &regs->i2c_ctrl);
+
+		rc = i2c_wait_complete(regs);
+
+		if (rc == 0) {
+			len--;
+			buffer++;
+			start_time_tx = get_timer(0);
+		} else if (get_timer(start_time_tx) > (nb * I2C_BYTE_TO)) {
+			return -ETIMEDOUT;
+		}
+	}
+
+	return 0;
+}
+
+static int ca_i2c_probe_chip(struct udevice *bus, uint chip_addr,
+			     uint chip_flags)
+{
+	struct ca_i2c *priv = dev_get_priv(bus);
+	int ret;
+	u32 tmp;
+
+	/* Try to read the first location of the chip */
+	ret = ca_i2c_read(priv->regs, chip_addr, 0, 1, (uchar *)&tmp, 1);
+	if (ret)
+		ca_i2c_init(priv->regs);
+
+	return ret;
+}
+
+static int ca_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
+{
+	struct ca_i2c *priv = dev_get_priv(bus);
+	int ret;
+
+	debug("i2c_xfer: %d messages\n", nmsgs);
+	for (; nmsgs > 0; nmsgs--, msg++) {
+		debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
+		if (msg->flags & I2C_M_RD)
+			ret = ca_i2c_read(priv->regs, msg->addr, 0, 0,
+					  msg->buf, msg->len);
+		else
+			ret = ca_i2c_write(priv->regs, msg->addr, 0, 0,
+					   msg->buf, msg->len);
+
+		if (ret) {
+			printf("i2c_xfer: %s error\n",
+			       msg->flags & I2C_M_RD ? "read" : "write");
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static const struct dm_i2c_ops ca_i2c_ops = {
+	.xfer		= ca_i2c_xfer,
+	.probe_chip	= ca_i2c_probe_chip,
+	.set_bus_speed	= ca_i2c_set_bus_speed,
+	.get_bus_speed	= ca_i2c_get_bus_speed,
+};
+
+static const struct udevice_id ca_i2c_ids[] = {
+	{ .compatible = "cortina,ca-i2c", },
+	{ }
+};
+
+static int ca_i2c_probe(struct udevice *bus)
+{
+	struct ca_i2c *priv = dev_get_priv(bus);
+
+	ca_i2c_init(priv->regs);
+
+	return 0;
+}
+
+static int ca_i2c_ofdata_to_platdata(struct udevice *bus)
+{
+	struct ca_i2c *priv = dev_get_priv(bus);
+
+	priv->regs = map_sysmem(dev_read_addr(bus), sizeof(struct i2c_regs));
+	if (!priv->regs) {
+		printf("I2C: base address is invalid\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+U_BOOT_DRIVER(i2c_cortina) = {
+	.name	= "i2c_cortina",
+	.id	= UCLASS_I2C,
+	.of_match = ca_i2c_ids,
+	.ofdata_to_platdata = ca_i2c_ofdata_to_platdata,
+	.probe	= ca_i2c_probe,
+	.priv_auto_alloc_size = sizeof(struct ca_i2c),
+	.ops	= &ca_i2c_ops,
+	.flags  = DM_FLAG_PRE_RELOC,
+};

+ 87 - 0
drivers/i2c/i2c-cortina.h

@@ -0,0 +1,87 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * (C) Copyright 2019
+ * Cortina Access, <www.cortina-access.com>
+ */
+
+#ifndef __CA_I2C_H_
+#define __CA_I2C_H_
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+
+#if !defined(__ASSEMBLER__) && !defined(__ASSEMBLY__)
+struct i2c_regs {
+	u32 i2c_cfg;
+	u32 i2c_ctrl;
+	u32 i2c_txr;
+	u32 i2c_rxr;
+	u32 i2c_ack;
+	u32 i2c_ie0;
+	u32 i2c_int0;
+	u32 i2c_ie1;
+	u32 i2c_int1;
+	u32 i2c_stat;
+};
+
+union ca_biw_cfg {
+	struct biw_cfg {
+		u32 core_en		: 1;
+		u32 biw_soft_reset	: 1;
+		u32 busywait_en		: 1;
+		u32 stretch_en		: 1;
+		u32 arb_en		: 1;
+		u32 clksync_en		: 1;
+		u32 rsrvd1		: 2;
+		u32 spike_cnt		: 4;
+		u32 rsrvd2		: 4;
+		u32 prer		: 16;
+	} bf;
+	unsigned int wrd;
+};
+
+union ca_biw_ctrl {
+	struct biw_ctrl {
+		u32 biwdone	: 1;
+		u32 rsrvd1	: 2;
+		u32 ack_in	: 1;
+		u32 write	: 1;
+		u32 read	: 1;
+		u32 stop	: 1;
+		u32 start	: 1;
+		u32 rsrvd2	: 24;
+	} bf;
+	unsigned int wrd;
+};
+
+union ca_biw_ack {
+	struct biw_ack {
+		u32 al		:1;
+		u32 biw_busy	:1;
+		u32 ack_out	:1;
+		u32 rsrvd1	:29;
+	} bf;
+	unsigned int wrd;
+};
+#endif /* !__ASSEMBLER__*/
+
+struct ca_i2c {
+	struct i2c_regs *regs;
+	unsigned int speed;
+};
+
+#define I2C_CMD_WT			0
+#define I2C_CMD_RD			1
+
+#define BIW_CTRL_DONE		BIT(0)
+#define BIW_CTRL_ACK_IN		BIT(3)
+#define BIW_CTRL_WRITE		BIT(4)
+#define BIW_CTRL_READ		BIT(5)
+#define BIW_CTRL_STOP		BIT(6)
+#define BIW_CTRL_START		BIT(7)
+
+#define I2C_BYTE_TO		(CONFIG_SYS_HZ / 500)
+#define I2C_STOPDET_TO		(CONFIG_SYS_HZ / 500)
+#define I2C_BYTE_TO_BB		(10)
+
+#endif							/* __CA_I2C_H_ */