drivers: mentor: extract MI2CV driver from Marvell driver

The Marvell A8K SoCs use the MI2CV IP core from Mentor Graphics, which
is also used by Allwinner.

As Mentor Graphics allows a lot of customization, the MI2CV in the two
SoC families are not compatible, and driver modifications are needed.

Extract the common code to a MI2CV driver.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>

1 files changed, 3 insertions, 584 deletions

diff --git a/drivers/marvell/i2c/a8k_i2c.c b/drivers/marvell/i2c/a8k_i2c.c
index fe8bc52e..1c0f922c 100644
--- a/drivers/marvell/i2c/a8k_i2c.c
+++ b/drivers/marvell/i2c/a8k_i2c.c
@@ -7,51 +7,15 @@
 
 /* This driver provides I2C support for Marvell A8K and compatible SoCs */
 
-#include <a8k_i2c.h>
-#include <debug.h>
-#include <delay_timer.h>
-#include <errno.h>
 #include <mmio.h>
-#include <mvebu_def.h>
-
-#if LOG_LEVEL >= LOG_LEVEL_VERBOSE
-#define DEBUG_I2C
-#endif
 
 #define CONFIG_SYS_TCLK			250000000
 #define CONFIG_SYS_I2C_SPEED		100000
 #define CONFIG_SYS_I2C_SLAVE		0x0
-#define I2C_TIMEOUT_VALUE		0x500
-#define I2C_MAX_RETRY_CNT		1000
-#define I2C_CMD_WRITE			0x0
-#define I2C_CMD_READ			0x1
-
-#define I2C_DATA_ADDR_7BIT_OFFS		0x1
-#define I2C_DATA_ADDR_7BIT_MASK		(0xFF << I2C_DATA_ADDR_7BIT_OFFS)
-
-#define I2C_CONTROL_ACK			0x00000004
-#define I2C_CONTROL_IFLG		0x00000008
-#define I2C_CONTROL_STOP		0x00000010
-#define I2C_CONTROL_START		0x00000020
-#define I2C_CONTROL_TWSIEN		0x00000040
-#define I2C_CONTROL_INTEN		0x00000080
-
-#define I2C_STATUS_START			0x08
-#define I2C_STATUS_REPEATED_START		0x10
-#define I2C_STATUS_ADDR_W_ACK			0x18
-#define I2C_STATUS_DATA_W_ACK			0x28
-#define I2C_STATUS_LOST_ARB_DATA_ADDR_TRANSFER	0x38
-#define I2C_STATUS_ADDR_R_ACK			0x40
-#define I2C_STATUS_DATA_R_ACK			0x50
-#define I2C_STATUS_DATA_R_NAK			0x58
-#define I2C_STATUS_LOST_ARB_GENERAL_CALL	0x78
-#define I2C_STATUS_IDLE				0xF8
 
-#define I2C_UNSTUCK_TRIGGER			0x1
-#define I2C_UNSTUCK_ONGOING			0x2
-#define I2C_UNSTUCK_ERROR			0x4
+#define I2C_CAN_UNSTUCK
 
-struct  marvell_i2c_regs {
+struct  mentor_i2c_regs {
 	uint32_t slave_address;
 	uint32_t data;
 	uint32_t control;
@@ -66,549 +30,4 @@ struct  marvell_i2c_regs {
 	uint32_t unstuck;
 };
 
-static struct marvell_i2c_regs *base;
-
-static int marvell_i2c_lost_arbitration(uint32_t *status)
-{
-	*status = mmio_read_32((uintptr_t)&base->status);
-	if ((*status == I2C_STATUS_LOST_ARB_DATA_ADDR_TRANSFER) ||
-	    (*status == I2C_STATUS_LOST_ARB_GENERAL_CALL))
-		return -EAGAIN;
-
-	return 0;
-}
-
-static void marvell_i2c_interrupt_clear(void)
-{
-	uint32_t reg;
-
-	reg = mmio_read_32((uintptr_t)&base->control);
-	reg &= ~(I2C_CONTROL_IFLG);
-	mmio_write_32((uintptr_t)&base->control, reg);
-	/* Wait for 1 us for the clear to take effect */
-	udelay(1);
-}
-
-static int marvell_i2c_interrupt_get(void)
-{
-	uint32_t reg;
-
-	/* get the interrupt flag bit */
-	reg = mmio_read_32((uintptr_t)&base->control);
-	reg &= I2C_CONTROL_IFLG;
-	return reg && I2C_CONTROL_IFLG;
-}
-
-static int marvell_i2c_wait_interrupt(void)
-{
-	uint32_t timeout = 0;
-
-	while (!marvell_i2c_interrupt_get() && (timeout++ < I2C_TIMEOUT_VALUE))
-		;
-	if (timeout >= I2C_TIMEOUT_VALUE)
-		return -ETIMEDOUT;
-
-	return 0;
-}
-
-static int marvell_i2c_start_bit_set(void)
-{
-	int is_int_flag = 0;
-	uint32_t status;
-
-	if (marvell_i2c_interrupt_get())
-		is_int_flag = 1;
-
-	/* set start bit */
-	mmio_write_32((uintptr_t)&base->control,
-		      mmio_read_32((uintptr_t)&base->control) |
-		      I2C_CONTROL_START);
-
-	/* in case that the int flag was set before i.e. repeated start bit */
-	if (is_int_flag) {
-		VERBOSE("%s: repeated start Bit\n", __func__);
-		marvell_i2c_interrupt_clear();
-	}
-
-	if (marvell_i2c_wait_interrupt()) {
-		ERROR("Start clear bit timeout\n");
-		return -ETIMEDOUT;
-	}
-
-	/* check that start bit went down */
-	if ((mmio_read_32((uintptr_t)&base->control) &
-	    I2C_CONTROL_START) != 0) {
-		ERROR("Start bit didn't went down\n");
-		return -EPERM;
-	}
-
-	/* check the status */
-	if (marvell_i2c_lost_arbitration(&status)) {
-		ERROR("%s - %d: Lost arbitration, got status %x\n",
-		      __func__, __LINE__, status);
-		return -EAGAIN;
-	}
-	if ((status != I2C_STATUS_START) &&
-	    (status != I2C_STATUS_REPEATED_START)) {
-		ERROR("Got status %x after enable start bit.\n", status);
-		return -EPERM;
-	}
-
-	return 0;
-}
-
-static int marvell_i2c_stop_bit_set(void)
-{
-	int timeout;
-	uint32_t status;
-
-	/* Generate stop bit */
-	mmio_write_32((uintptr_t)&base->control,
-		      mmio_read_32((uintptr_t)&base->control) |
-		      I2C_CONTROL_STOP);
-	marvell_i2c_interrupt_clear();
-
-	timeout = 0;
-	/* Read control register, check the control stop bit */
-	while ((mmio_read_32((uintptr_t)&base->control) & I2C_CONTROL_STOP) &&
-	       (timeout++ < I2C_TIMEOUT_VALUE))
-		;
-	if (timeout >= I2C_TIMEOUT_VALUE) {
-		ERROR("Stop bit didn't went down\n");
-		return -ETIMEDOUT;
-	}
-
-	/* check that stop bit went down */
-	if ((mmio_read_32((uintptr_t)&base->control) & I2C_CONTROL_STOP) != 0) {
-		ERROR("Stop bit didn't went down\n");
-		return -EPERM;
-	}
-
-	/* check the status */
-	if (marvell_i2c_lost_arbitration(&status)) {
-		ERROR("%s - %d: Lost arbitration, got status %x\n",
-		      __func__, __LINE__, status);
-		return -EAGAIN;
-	}
-	if (status != I2C_STATUS_IDLE) {
-		ERROR("Got status %x after enable stop bit.\n", status);
-		return -EPERM;
-	}
-
-	return 0;
-}
-
-static int marvell_i2c_address_set(uint8_t chain, int command)
-{
-	uint32_t reg, status;
-
-	reg = (chain << I2C_DATA_ADDR_7BIT_OFFS) & I2C_DATA_ADDR_7BIT_MASK;
-	reg |= command;
-	mmio_write_32((uintptr_t)&base->data, reg);
-	udelay(1);
-
-	marvell_i2c_interrupt_clear();
-
-	if (marvell_i2c_wait_interrupt()) {
-		ERROR("Start clear bit timeout\n");
-		return -ETIMEDOUT;
-	}
-
-	/* check the status */
-	if (marvell_i2c_lost_arbitration(&status)) {
-		ERROR("%s - %d: Lost arbitration, got status %x\n",
-		      __func__, __LINE__, status);
-		return -EAGAIN;
-	}
-	if (((status != I2C_STATUS_ADDR_R_ACK) && (command == I2C_CMD_READ)) ||
-	   ((status != I2C_STATUS_ADDR_W_ACK) && (command == I2C_CMD_WRITE))) {
-		/* only in debug, since in boot we try to read the SPD
-		 * of both DRAM, and we don't want error messages in cas
-		 * DIMM doesn't exist.
-		 */
-		INFO("%s: ERROR - status %x addr in %s mode.\n", __func__,
-		     status, (command == I2C_CMD_WRITE) ? "Write" : "Read");
-		return -EPERM;
-	}
-
-	return 0;
-}
-
-/*
- * The I2C module contains a clock divider to generate the SCL clock.
- * This function calculates and sets the <N> and <M> fields in the I2C Baud
- * Rate Register (t=01) to obtain given 'requested_speed'.
- * The requested_speed will be equal to:
- * CONFIG_SYS_TCLK / (10 * (M + 1) * (2 << N))
- * Where M is the value represented by bits[6:3] and N is the value represented
- * by bits[2:0] of "I2C Baud Rate Register".
- * Therefore max M which can be set is 16 (2^4) and max N is 8 (2^3). So the
- * lowest possible baudrate is:
- * CONFIG_SYS_TCLK/(10 * (16 +1) * (2 << 8), which equals to:
- * CONFIG_SYS_TCLK/87040. Assuming that CONFIG_SYS_TCLK=250MHz, the lowest
- * possible frequency is ~2,872KHz.
- */
-static unsigned int marvell_i2c_bus_speed_set(unsigned int requested_speed)
-{
-	unsigned int n, m, freq, margin, min_margin = 0xffffffff;
-	unsigned int actual_n = 0, actual_m = 0;
-	int val;
-
-	/* Calculate N and M for the TWSI clock baud rate */
-	for (n = 0; n < 8; n++) {
-		for (m = 0; m < 16; m++) {
-			freq = CONFIG_SYS_TCLK / (10 * (m + 1) * (2 << n));
-			val = requested_speed - freq;
-			margin = (val > 0) ? val : -val;
-
-			if ((freq <= requested_speed) &&
-			    (margin < min_margin)) {
-				min_margin = margin;
-				actual_n = n;
-				actual_m = m;
-			}
-		}
-	}
-	VERBOSE("%s: actual_n = %u, actual_m = %u\n",
-		__func__, actual_n, actual_m);
-	/* Set the baud rate */
-	mmio_write_32((uintptr_t)&base->baudrate, (actual_m << 3) | actual_n);
-
-	return 0;
-}
-
-#ifdef DEBUG_I2C
-static int marvell_i2c_probe(uint8_t chip)
-{
-	int ret = 0;
-
-	ret = marvell_i2c_start_bit_set();
-	if (ret != 0) {
-		marvell_i2c_stop_bit_set();
-		ERROR("%s - %d: %s", __func__, __LINE__,
-		      "marvell_i2c_start_bit_set failed\n");
-		return -EPERM;
-	}
-
-	ret = marvell_i2c_address_set(chip, I2C_CMD_WRITE);
-	if (ret != 0) {
-		marvell_i2c_stop_bit_set();
-		ERROR("%s - %d: %s", __func__, __LINE__,
-		      "marvell_i2c_address_set failed\n");
-		return -EPERM;
-	}
-
-	marvell_i2c_stop_bit_set();
-
-	VERBOSE("%s: successful I2C probe\n", __func__);
-
-	return ret;
-}
-#endif
-
-/* regular i2c transaction */
-static int marvell_i2c_data_receive(uint8_t *p_block, uint32_t block_size)
-{
-	uint32_t reg, status, block_size_read = block_size;
-
-	/* Wait for cause interrupt */
-	if (marvell_i2c_wait_interrupt()) {
-		ERROR("Start clear bit timeout\n");
-		return -ETIMEDOUT;
-	}
-	while (block_size_read) {
-		if (block_size_read == 1) {
-			reg = mmio_read_32((uintptr_t)&base->control);
-			reg &= ~(I2C_CONTROL_ACK);
-			mmio_write_32((uintptr_t)&base->control, reg);
-		}
-		marvell_i2c_interrupt_clear();
-
-		if (marvell_i2c_wait_interrupt()) {
-			ERROR("Start clear bit timeout\n");
-			return -ETIMEDOUT;
-		}
-		/* check the status */
-		if (marvell_i2c_lost_arbitration(&status)) {
-			ERROR("%s - %d: Lost arbitration, got status %x\n",
-			      __func__, __LINE__, status);
-			return -EAGAIN;
-		}
-		if ((status != I2C_STATUS_DATA_R_ACK) &&
-		    (block_size_read != 1)) {
-			ERROR("Status %x in read transaction\n", status);
-			return -EPERM;
-		}
-		if ((status != I2C_STATUS_DATA_R_NAK) &&
-		    (block_size_read == 1)) {
-			ERROR("Status %x in Rd Terminate\n", status);
-			return -EPERM;
-		}
-
-		/* read the data */
-		*p_block = (uint8_t) mmio_read_32((uintptr_t)&base->data);
-		VERBOSE("%s: place %d read %x\n", __func__,
-			block_size - block_size_read, *p_block);
-		p_block++;
-		block_size_read--;
-	}
-
-	return 0;
-}
-
-static int marvell_i2c_data_transmit(uint8_t *p_block, uint32_t block_size)
-{
-	uint32_t status, block_size_write = block_size;
-
-	if (marvell_i2c_wait_interrupt()) {
-		ERROR("Start clear bit timeout\n");
-		return -ETIMEDOUT;
-	}
-
-	while (block_size_write) {
-		/* write the data */
-		mmio_write_32((uintptr_t)&base->data, (uint32_t) *p_block);
-		VERBOSE("%s: index = %d, data = %x\n", __func__,
-			block_size - block_size_write, *p_block);
-		p_block++;
-		block_size_write--;
-
-		marvell_i2c_interrupt_clear();
-
-		if (marvell_i2c_wait_interrupt()) {
-			ERROR("Start clear bit timeout\n");
-			return -ETIMEDOUT;
-		}
-
-		/* check the status */
-		if (marvell_i2c_lost_arbitration(&status)) {
-			ERROR("%s - %d: Lost arbitration, got status %x\n",
-			      __func__, __LINE__, status);
-			return -EAGAIN;
-		}
-		if (status != I2C_STATUS_DATA_W_ACK) {
-			ERROR("Status %x in write transaction\n", status);
-			return -EPERM;
-		}
-	}
-
-	return 0;
-}
-
-static int marvell_i2c_target_offset_set(uint8_t chip, uint32_t addr, int alen)
-{
-	uint8_t off_block[2];
-	uint32_t off_size;
-
-	if (alen == 2) { /* 2-byte addresses support */
-		off_block[0] = (addr >> 8) & 0xff;
-		off_block[1] = addr & 0xff;
-		off_size = 2;
-	} else { /* 1-byte addresses support */
-		off_block[0] = addr & 0xff;
-		off_size = 1;
-	}
-	VERBOSE("%s: off_size = %x addr1 = %x addr2 = %x\n", __func__,
-		off_size, off_block[0], off_block[1]);
-	return marvell_i2c_data_transmit(off_block, off_size);
-}
-
-static int marvell_i2c_unstuck(int ret)
-{
-	uint32_t v;
-
-	if (ret != -ETIMEDOUT)
-		return ret;
-	VERBOSE("Trying to \"unstuck i2c\"... ");
-	i2c_init(base);
-	mmio_write_32((uintptr_t)&base->unstuck, I2C_UNSTUCK_TRIGGER);
-	do {
-		v = mmio_read_32((uintptr_t)&base->unstuck);
-	} while (v & I2C_UNSTUCK_ONGOING);
-
-	if (v & I2C_UNSTUCK_ERROR) {
-		VERBOSE("failed - soft reset i2c\n");
-		ret = -EPERM;
-	} else {
-		VERBOSE("ok\n");
-		i2c_init(base);
-		ret = -EAGAIN;
-	}
-	return ret;
-}
-
-/*
- * API Functions
- */
-void i2c_init(void *i2c_base)
-{
-	/* For I2C speed and slave address, now we do not set them since
-	 * we just provide the working speed and slave address in mvebu_def.h
-	 * for i2c_init
-	 */
-	base = (struct marvell_i2c_regs *)i2c_base;
-
-	/* Reset the I2C logic */
-	mmio_write_32((uintptr_t)&base->soft_reset, 0);
-
-	udelay(200);
-
-	marvell_i2c_bus_speed_set(CONFIG_SYS_I2C_SPEED);
-
-	/* Enable the I2C and slave */
-	mmio_write_32((uintptr_t)&base->control,
-		      I2C_CONTROL_TWSIEN | I2C_CONTROL_ACK);
-
-	/* set the I2C slave address */
-	mmio_write_32((uintptr_t)&base->xtnd_slave_addr, 0);
-	mmio_write_32((uintptr_t)&base->slave_address, CONFIG_SYS_I2C_SLAVE);
-
-	/* unmask I2C interrupt */
-	mmio_write_32((uintptr_t)&base->control,
-		      mmio_read_32((uintptr_t)&base->control) |
-		      I2C_CONTROL_INTEN);
-
-	udelay(10);
-}
-
-/*
- * i2c_read: - Read multiple bytes from an i2c device
- *
- * The higher level routines take into account that this function is only
- * called with len < page length of the device (see configuration file)
- *
- * @chip:	address of the chip which is to be read
- * @addr:	i2c data address within the chip
- * @alen:	length of the i2c data address (1..2 bytes)
- * @buffer:	where to write the data
- * @len:	how much byte do we want to read
- * @return:	0 in case of success
- */
-int i2c_read(uint8_t chip, uint32_t addr, int alen, uint8_t *buffer, int len)
-{
-	int ret = 0;
-	uint32_t counter = 0;
-
-#ifdef DEBUG_I2C
-	marvell_i2c_probe(chip);
-#endif
-
-	do {
-		if (ret != -EAGAIN && ret) {
-			ERROR("i2c transaction failed, after %d retries\n",
-			      counter);
-			marvell_i2c_stop_bit_set();
-			return ret;
-		}
-
-		/* wait for 1 us for the interrupt clear to take effect */
-		if (counter > 0)
-			udelay(1);
-		counter++;
-
-		ret = marvell_i2c_start_bit_set();
-		if (ret) {
-			ret = marvell_i2c_unstuck(ret);
-			continue;
-		}
-
-		/* if EEPROM device */
-		if (alen != 0) {
-			ret = marvell_i2c_address_set(chip, I2C_CMD_WRITE);
-			if (ret)
-				continue;
-
-			ret = marvell_i2c_target_offset_set(chip, addr, alen);
-			if (ret)
-				continue;
-			ret = marvell_i2c_start_bit_set();
-			if (ret)
-				continue;
-		}
-
-		ret =  marvell_i2c_address_set(chip, I2C_CMD_READ);
-		if (ret)
-			continue;
-
-		ret = marvell_i2c_data_receive(buffer, len);
-		if (ret)
-			continue;
-
-		ret =  marvell_i2c_stop_bit_set();
-	} while ((ret == -EAGAIN) && (counter < I2C_MAX_RETRY_CNT));
-
-	if (counter == I2C_MAX_RETRY_CNT) {
-		ERROR("I2C transactions failed, got EAGAIN %d times\n",
-		      I2C_MAX_RETRY_CNT);
-		ret = -EPERM;
-	}
-	mmio_write_32((uintptr_t)&base->control,
-		      mmio_read_32((uintptr_t)&base->control) |
-		      I2C_CONTROL_ACK);
-
-	udelay(1);
-	return ret;
-}
-
-/*
- * i2c_write: -  Write multiple bytes to an i2c device
- *
- * The higher level routines take into account that this function is only
- * called with len < page length of the device (see configuration file)
- *
- * @chip:	address of the chip which is to be written
- * @addr:	i2c data address within the chip
- * @alen:	length of the i2c data address (1..2 bytes)
- * @buffer:	where to find the data to be written
- * @len:	how much byte do we want to read
- * @return:	0 in case of success
- */
-int i2c_write(uint8_t chip, uint32_t addr, int alen, uint8_t *buffer, int len)
-{
-	int ret = 0;
-	uint32_t counter = 0;
-
-	do {
-		if (ret != -EAGAIN && ret) {
-			ERROR("i2c transaction failed\n");
-			marvell_i2c_stop_bit_set();
-			return ret;
-		}
-		/* wait for 1 us for the interrupt clear to take effect */
-		if (counter > 0)
-			udelay(1);
-		counter++;
-
-		ret = marvell_i2c_start_bit_set();
-		if (ret) {
-			ret = marvell_i2c_unstuck(ret);
-			continue;
-		}
-
-		ret = marvell_i2c_address_set(chip, I2C_CMD_WRITE);
-		if (ret)
-			continue;
-
-		/* if EEPROM device */
-		if (alen != 0) {
-			ret = marvell_i2c_target_offset_set(chip, addr, alen);
-			if (ret)
-				continue;
-		}
-
-		ret = marvell_i2c_data_transmit(buffer, len);
-		if (ret)
-			continue;
-
-		ret = marvell_i2c_stop_bit_set();
-	} while ((ret == -EAGAIN) && (counter < I2C_MAX_RETRY_CNT));
-
-	if (counter == I2C_MAX_RETRY_CNT) {
-		ERROR("I2C transactions failed, got EAGAIN %d times\n",
-		      I2C_MAX_RETRY_CNT);
-		ret = -EPERM;
-	}
-
-	udelay(1);
-	return ret;
-}
+#include "../../mentor/i2c/mi2cv.c"