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/***********************license start***************
 * Copyright (c) 2003-2010  Cavium Inc. (support@cavium.com). All rights
 * reserved.
 *
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   * Redistributions in binary form must reproduce the above
 *     copyright notice, this list of conditions and the following
 *     disclaimer in the documentation and/or other materials provided
 *     with the distribution.

 *   * Neither the name of Cavium Inc. nor the names of
 *     its contributors may be used to endorse or promote products
 *     derived from this software without specific prior written
 *     permission.

 * This Software, including technical data, may be subject to U.S. export  control
 * laws, including the U.S. Export Administration Act and its  associated
 * regulations, and may be subject to export or import  regulations in other
 * countries.

 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, THE SOFTWARE IS PROVIDED "AS IS"
 * AND WITH ALL FAULTS AND CAVIUM INC. MAKES NO PROMISES, REPRESENTATIONS OR
 * WARRANTIES, EITHER EXPRESS, IMPLIED, STATUTORY, OR OTHERWISE, WITH RESPECT TO
 * THE SOFTWARE, INCLUDING ITS CONDITION, ITS CONFORMITY TO ANY REPRESENTATION OR
 * DESCRIPTION, OR THE EXISTENCE OF ANY LATENT OR PATENT DEFECTS, AND CAVIUM
 * SPECIFICALLY DISCLAIMS ALL IMPLIED (IF ANY) WARRANTIES OF TITLE,
 * MERCHANTABILITY, NONINFRINGEMENT, FITNESS FOR A PARTICULAR PURPOSE, LACK OF
 * VIRUSES, ACCURACY OR COMPLETENESS, QUIET ENJOYMENT, QUIET POSSESSION OR
 * CORRESPONDENCE TO DESCRIPTION. THE ENTIRE  RISK ARISING OUT OF USE OR
 * PERFORMANCE OF THE SOFTWARE LIES WITH YOU.
 ***********************license end**************************************/







/**
 * @file
 *
 * Interface to the TWSI / I2C bus
 *
 * <hr>$Revision: 70030 $<hr>
 *
 */
#ifdef CVMX_BUILD_FOR_LINUX_KERNEL
#include <linux/i2c.h>

#include <asm/octeon/cvmx.h>
#include <asm/octeon/cvmx-twsi.h>
#else
#include "cvmx.h"
#include "cvmx-twsi.h"
#include "cvmx-csr-db.h"
#endif

//#define PRINT_TWSI_CONFIG
#ifdef PRINT_TWSI_CONFIG
#define twsi_printf printf
#else
#define twsi_printf(...)
#define cvmx_csr_db_decode(...)
#endif

#ifdef CVMX_BUILD_FOR_LINUX_KERNEL
# if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
static struct i2c_adapter *__cvmx_twsix_get_adapter(int twsi_id)
{
	struct octeon_i2c {
		wait_queue_head_t queue;
		struct i2c_adapter adap;
		int irq;
		int twsi_freq;
		int sys_freq;
		resource_size_t twsi_phys;
		void __iomem *twsi_base;
		resource_size_t regsize;
		struct device *dev;
		int broken_irq_mode;
	};
	struct i2c_adapter *adapter;
	struct octeon_i2c *i2c;

	adapter = i2c_get_adapter(0);
	if (adapter == NULL)
		return NULL;
	i2c = container_of(adapter, struct octeon_i2c, adap);
	return &i2c[twsi_id].adap;
}
#endif
#endif


/**
 * Do a twsi read from a 7 bit device address using an (optional) internal address.
 * Up to 8 bytes can be read at a time.
 *
 * @param twsi_id   which Octeon TWSI bus to use
 * @param dev_addr  Device address (7 bit)
 * @param internal_addr
 *                  Internal address.  Can be 0, 1 or 2 bytes in width
 * @param num_bytes Number of data bytes to read
 * @param ia_width_bytes
 *                  Internal address size in bytes (0, 1, or 2)
 * @param data      Pointer argument where the read data is returned.
 *
 * @return read data returned in 'data' argument
 *         Number of bytes read on success
 *         -1 on failure
 */
int cvmx_twsix_read_ia(int twsi_id, uint8_t dev_addr, uint16_t internal_addr, int num_bytes, int ia_width_bytes, uint64_t *data)
{
#ifdef CVMX_BUILD_FOR_LINUX_KERNEL
# if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
	struct i2c_adapter *adapter;
	u8 data_buf[8];
	u8 addr_buf[8];
	struct i2c_msg msg[2];
	uint64_t r;
	int i, j;

	if (ia_width_bytes == 0)
		return cvmx_twsix_read(twsi_id, dev_addr, num_bytes, data);

	BUG_ON(ia_width_bytes > 2);
	BUG_ON(num_bytes > 8 || num_bytes < 1);

	adapter = __cvmx_twsix_get_adapter(twsi_id);
	if (adapter == NULL)
		return -1;

	for (j = 0, i = ia_width_bytes - 1; i >= 0; i--, j++)
		addr_buf[j] = (u8)(internal_addr >> (i * 8));

	msg[0].addr = dev_addr;
	msg[0].flags = 0;
	msg[0].len = ia_width_bytes;
	msg[0].buf = addr_buf;

	msg[1].addr = dev_addr;
	msg[1].flags = I2C_M_RD;
	msg[1].len = num_bytes;
	msg[1].buf = data_buf;

	i = i2c_transfer(adapter, msg, 2);

	i2c_put_adapter(adapter);

	if (i == 2) {
		r = 0;
		for (i = 0; i < num_bytes; i++)
			r = (r << 8) | data_buf[i];
		*data = r;
		return num_bytes;
	} else {
		return -1;
	}
# else
	BUG(); /* The I2C driver is not compiled in */
# endif
#else
	cvmx_mio_twsx_sw_twsi_t sw_twsi_val;
	cvmx_mio_twsx_sw_twsi_ext_t twsi_ext;
        int retry_limit = 5;

	if (num_bytes < 1 || num_bytes > 8 || !data || ia_width_bytes < 0 || ia_width_bytes > 2)
		return -1;
retry:
	twsi_ext.u64 = 0;
	sw_twsi_val.u64 = 0;
	sw_twsi_val.s.v = 1;
	sw_twsi_val.s.r = 1;
	sw_twsi_val.s.sovr = 1;
	sw_twsi_val.s.size = num_bytes - 1;
	sw_twsi_val.s.a = dev_addr;

	if (ia_width_bytes > 0) {
		sw_twsi_val.s.op = 1;
		sw_twsi_val.s.ia = (internal_addr >> 3) & 0x1f;
		sw_twsi_val.s.eop_ia = internal_addr & 0x7;
	}
	if (ia_width_bytes == 2) {
		sw_twsi_val.s.eia = 1;
		twsi_ext.s.ia = internal_addr >> 8;
		cvmx_write_csr(CVMX_MIO_TWSX_SW_TWSI_EXT(twsi_id), twsi_ext.u64);
	}

	cvmx_csr_db_decode(cvmx_get_proc_id(), CVMX_MIO_TWSX_SW_TWSI(twsi_id), sw_twsi_val.u64);
	cvmx_write_csr(CVMX_MIO_TWSX_SW_TWSI(twsi_id), sw_twsi_val.u64);
	while (((cvmx_mio_twsx_sw_twsi_t)(sw_twsi_val.u64 = cvmx_read_csr(CVMX_MIO_TWSX_SW_TWSI(twsi_id)))).s.v)
		cvmx_wait(1000);
	twsi_printf("Results:\n");
	cvmx_csr_db_decode(cvmx_get_proc_id(), CVMX_MIO_TWSX_SW_TWSI(twsi_id), sw_twsi_val.u64);
	if (!sw_twsi_val.s.r)
        {
            /* Check the reason for the failure.  We may need to retry to handle multi-master
            ** configurations.
            ** Lost arbitration : 0x38, 0x68, 0xB0, 0x78
            ** Core busy as slave: 0x80, 0x88, 0xA0, 0xA8, 0xB8, 0xC0, 0xC8
            */
            if (sw_twsi_val.s.d == 0x38
                || sw_twsi_val.s.d == 0x68
                || sw_twsi_val.s.d == 0xB0
                || sw_twsi_val.s.d == 0x78
                || sw_twsi_val.s.d == 0x80
                || sw_twsi_val.s.d == 0x88
                || sw_twsi_val.s.d == 0xA0
                || sw_twsi_val.s.d == 0xA8
                || sw_twsi_val.s.d == 0xB8
                || sw_twsi_val.s.d == 0xC8)
            {
                if (retry_limit-- > 0)
                {
                    cvmx_wait_usec(100);
                    goto retry;
                }
            }
            /* For all other errors, return an error code */
            return -1;
        }

	*data = (sw_twsi_val.s.d & (0xFFFFFFFF >> (32 - num_bytes*8)));
	if (num_bytes > 4) {
		twsi_ext.u64 = cvmx_read_csr(CVMX_MIO_TWSX_SW_TWSI_EXT(twsi_id));
		*data |= ((unsigned long long)(twsi_ext.s.d & (0xFFFFFFFF >> (32 - num_bytes*8))) << 32);
	}
	return num_bytes;
#endif
}

/**
 * Read from a TWSI device (7 bit device address only) without generating any
 * internal addresses.
 * Read from 1-8 bytes and returns them in the data pointer.
 *
 * @param twsi_id   TWSI interface on Octeon to use
 * @param dev_addr  TWSI device address (7 bit only)
 * @param num_bytes number of bytes to read
 * @param data      Pointer to data read from TWSI device
 *
 * @return Number of bytes read on success
 *         -1 on error
 */
int cvmx_twsix_read(int twsi_id, uint8_t dev_addr, int num_bytes, uint64_t *data)
{
#ifdef CVMX_BUILD_FOR_LINUX_KERNEL
# if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
	struct i2c_adapter *adapter;
	u8 data_buf[8];
	struct i2c_msg msg[1];
	uint64_t r;
	int i;

	BUG_ON(num_bytes > 8 || num_bytes < 1);

	adapter = __cvmx_twsix_get_adapter(twsi_id);
	if (adapter == NULL)
		return -1;

	msg[0].addr = dev_addr;
	msg[0].flags = I2C_M_RD;
	msg[0].len = num_bytes;
	msg[0].buf = data_buf;

	i = i2c_transfer(adapter, msg, 1);

	i2c_put_adapter(adapter);

	if (i == 1) {
		r = 0;
		for (i = 0; i < num_bytes; i++)
			r = (r << 8) | data_buf[i];
		*data = r;
		return num_bytes;
	} else {
		return -1;
	}
# else
	BUG(); /* The I2C driver is not compiled in */
# endif
#else
	cvmx_mio_twsx_sw_twsi_t sw_twsi_val;
	cvmx_mio_twsx_sw_twsi_ext_t twsi_ext;
        int retry_limit = 5;

	if (num_bytes > 8 || num_bytes < 1)
		return -1;
retry:
	sw_twsi_val.u64 = 0;
	sw_twsi_val.s.v = 1;
	sw_twsi_val.s.r = 1;
	sw_twsi_val.s.a = dev_addr;
	sw_twsi_val.s.sovr = 1;
	sw_twsi_val.s.size = num_bytes - 1;

	cvmx_csr_db_decode(cvmx_get_proc_id(), CVMX_MIO_TWSX_SW_TWSI(twsi_id), sw_twsi_val.u64);
	cvmx_write_csr(CVMX_MIO_TWSX_SW_TWSI(twsi_id), sw_twsi_val.u64);
	while (((cvmx_mio_twsx_sw_twsi_t)(sw_twsi_val.u64 = cvmx_read_csr(CVMX_MIO_TWSX_SW_TWSI(twsi_id)))).s.v)
            cvmx_wait(1000);
	twsi_printf("Results:\n");
	cvmx_csr_db_decode(cvmx_get_proc_id(), CVMX_MIO_TWSX_SW_TWSI(twsi_id), sw_twsi_val.u64);
	if (!sw_twsi_val.s.r)
            if (!sw_twsi_val.s.r)
            {
                /* Check the reason for the failure.  We may need to retry to handle multi-master
                ** configurations.
                ** Lost arbitration : 0x38, 0x68, 0xB0, 0x78
                ** Core busy as slave: 0x80, 0x88, 0xA0, 0xA8, 0xB8, 0xC0, 0xC8
                */
                if (sw_twsi_val.s.d == 0x38
                    || sw_twsi_val.s.d == 0x68
                    || sw_twsi_val.s.d == 0xB0
                    || sw_twsi_val.s.d == 0x78
                    || sw_twsi_val.s.d == 0x80
                    || sw_twsi_val.s.d == 0x88
                    || sw_twsi_val.s.d == 0xA0
                    || sw_twsi_val.s.d == 0xA8
                    || sw_twsi_val.s.d == 0xB8
                    || sw_twsi_val.s.d == 0xC8)
                {
                    if (retry_limit-- > 0)
                    {
                        cvmx_wait_usec(100);
                        goto retry;
                     }
                }
                /* For all other errors, return an error code */
                return -1;
            }

	*data = (sw_twsi_val.s.d & (0xFFFFFFFF >> (32 - num_bytes*8)));
	if (num_bytes > 4) {
		twsi_ext.u64 = cvmx_read_csr(CVMX_MIO_TWSX_SW_TWSI_EXT(twsi_id));
		*data |= ((unsigned long long)(twsi_ext.s.d & (0xFFFFFFFF >> (32 - num_bytes*8))) << 32);
	}
	return num_bytes;
#endif
}

/**
 * Perform a twsi write operation to a 7 bit device address.
 *
 * Note that many eeprom devices have page restrictions regarding address boundaries
 * that can be crossed in one write operation.  This is device dependent, and this routine
 * does nothing in this regard.
 * This command does not generate any internal addressess.
 *
 * @param twsi_id   Octeon TWSI interface to use
 * @param dev_addr  TWSI device address
 * @param num_bytes Number of bytes to write (between 1 and 8 inclusive)
 * @param data      Data to write
 *
 * @return 0 on success
 *         -1 on failure
 */
int cvmx_twsix_write(int twsi_id, uint8_t dev_addr, int num_bytes, uint64_t data)
{
#ifdef CVMX_BUILD_FOR_LINUX_KERNEL
# if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
	struct i2c_adapter *adapter;
	u8 data_buf[8];
	struct i2c_msg msg[1];
	int i, j;

	BUG_ON(num_bytes > 8 || num_bytes < 1);

	adapter = __cvmx_twsix_get_adapter(twsi_id);
	if (adapter == NULL)
		return -1;

	for (j = 0, i = num_bytes - 1; i >= 0; i--, j++)
		data_buf[j] = (u8)(data >> (i * 8));

	msg[0].addr = dev_addr;
	msg[0].flags = 0;
	msg[0].len = num_bytes;
	msg[0].buf = data_buf;

	i = i2c_transfer(adapter, msg, 1);

	i2c_put_adapter(adapter);

	if (i == 1)
		return num_bytes;
	else
		return -1;
# else
	BUG(); /* The I2C driver is not compiled in */
# endif
#else
	cvmx_mio_twsx_sw_twsi_t sw_twsi_val;

	if (num_bytes > 8 || num_bytes < 1)
		return -1;

	sw_twsi_val.u64 = 0;
	sw_twsi_val.s.v = 1;
	sw_twsi_val.s.a = dev_addr;
	sw_twsi_val.s.d = data & 0xffffffff;
	sw_twsi_val.s.sovr = 1;
	sw_twsi_val.s.size = num_bytes - 1;
	if (num_bytes > 4) {
		/* Upper four bytes go into a separate register */
		cvmx_mio_twsx_sw_twsi_ext_t twsi_ext;
		twsi_ext.u64 = 0;
		twsi_ext.s.d = data >> 32;
		cvmx_write_csr(CVMX_MIO_TWSX_SW_TWSI_EXT(twsi_id), twsi_ext.u64);
	}
	cvmx_csr_db_decode(cvmx_get_proc_id(), CVMX_MIO_TWSX_SW_TWSI(twsi_id), sw_twsi_val.u64);
	cvmx_write_csr(CVMX_MIO_TWSX_SW_TWSI(twsi_id), sw_twsi_val.u64);
	while (((cvmx_mio_twsx_sw_twsi_t)(sw_twsi_val.u64 = cvmx_read_csr(CVMX_MIO_TWSX_SW_TWSI(twsi_id)))).s.v)
		;
	twsi_printf("Results:\n");
	cvmx_csr_db_decode(cvmx_get_proc_id(), CVMX_MIO_TWSX_SW_TWSI(twsi_id), sw_twsi_val.u64);
	if (!sw_twsi_val.s.r)
		return -1;

	return 0;
#endif
}

/**
 * Write 1-8 bytes to a TWSI device using an internal address.
 *
 * @param twsi_id   which TWSI interface on Octeon to use
 * @param dev_addr  TWSI device address (7 bit only)
 * @param internal_addr
 *                  TWSI internal address (0, 8, or 16 bits)
 * @param num_bytes Number of bytes to write (1-8)
 * @param ia_width_bytes
 *                  internal address width, in bytes (0, 1, 2)
 * @param data      Data to write.  Data is written MSB first on the twsi bus, and only the lower
 *                  num_bytes bytes of the argument are valid.  (If a 2 byte write is done, only
 *                  the low 2 bytes of the argument is used.
 *
 * @return Number of bytes read on success,
 *         -1 on error
 */
int cvmx_twsix_write_ia(int twsi_id, uint8_t dev_addr, uint16_t internal_addr, int num_bytes, int ia_width_bytes, uint64_t data)
{
#ifdef CVMX_BUILD_FOR_LINUX_KERNEL
# if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
	struct i2c_adapter *adapter;
	u8 data_buf[8];
	u8 addr_buf[8];
	struct i2c_msg msg[2];
	int i, j;

	if (ia_width_bytes == 0)
		return cvmx_twsix_write(twsi_id, dev_addr, num_bytes, data);

	BUG_ON(ia_width_bytes > 2);
	BUG_ON(num_bytes > 8 || num_bytes < 1);

	adapter = __cvmx_twsix_get_adapter(twsi_id);
	if (adapter == NULL)
		return -1;


	for (j = 0, i = ia_width_bytes - 1; i >= 0; i--, j++)
		addr_buf[j] = (u8)(internal_addr >> (i * 8));

	for (j = 0, i = num_bytes - 1; i >= 0; i--, j++)
		data_buf[j] = (u8)(data >> (i * 8));

	msg[0].addr = dev_addr;
	msg[0].flags = 0;
	msg[0].len = ia_width_bytes;
	msg[0].buf = addr_buf;

	msg[1].addr = dev_addr;
	msg[1].flags = 0;
	msg[1].len = num_bytes;
	msg[1].buf = data_buf;

	i = i2c_transfer(adapter, msg, 2);

	i2c_put_adapter(adapter);

	if (i == 2) {
		/* Poll until reads succeed, or polling times out */
		int to = 100;
		while (to-- > 0) {
			uint64_t data;
			if (cvmx_twsix_read(twsi_id, dev_addr, 1, &data) >= 0)
				break;
		}
	}

	if (i == 2)
		return num_bytes;
	else
		return -1;
# else
	BUG(); /* The I2C driver is not compiled in */
# endif
#else
	cvmx_mio_twsx_sw_twsi_t sw_twsi_val;
	cvmx_mio_twsx_sw_twsi_ext_t twsi_ext;
	int to;

	if (num_bytes < 1 || num_bytes > 8 || ia_width_bytes < 0 || ia_width_bytes > 2)
		return -1;

	twsi_ext.u64 = 0;

	sw_twsi_val.u64 = 0;
	sw_twsi_val.s.v = 1;
	sw_twsi_val.s.sovr = 1;
	sw_twsi_val.s.size = num_bytes - 1;
	sw_twsi_val.s.a = dev_addr;
	sw_twsi_val.s.d = 0xFFFFFFFF & data;

	if (ia_width_bytes > 0) {
		sw_twsi_val.s.op = 1;
		sw_twsi_val.s.ia = (internal_addr >> 3) & 0x1f;
		sw_twsi_val.s.eop_ia = internal_addr & 0x7;
	}
	if (ia_width_bytes == 2) {
		sw_twsi_val.s.eia = 1;
		twsi_ext.s.ia = internal_addr >> 8;
	}
	if (num_bytes > 4)
		twsi_ext.s.d = data >> 32;

	twsi_printf("%s: twsi_id=%x, dev_addr=%x, internal_addr=%x\n\tnum_bytes=%d, ia_width_bytes=%d, data=%lx\n",
		    __FUNCTION__, twsi_id, dev_addr, internal_addr, num_bytes, ia_width_bytes, data);
	cvmx_csr_db_decode(cvmx_get_proc_id(), CVMX_MIO_TWSX_SW_TWSI_EXT(twsi_id), twsi_ext.u64);
	cvmx_write_csr(CVMX_MIO_TWSX_SW_TWSI_EXT(twsi_id), twsi_ext.u64);
	cvmx_csr_db_decode(cvmx_get_proc_id(), CVMX_MIO_TWSX_SW_TWSI(twsi_id), sw_twsi_val.u64);
	cvmx_write_csr(CVMX_MIO_TWSX_SW_TWSI(twsi_id), sw_twsi_val.u64);
	while (((cvmx_mio_twsx_sw_twsi_t)(sw_twsi_val.u64 = cvmx_read_csr(CVMX_MIO_TWSX_SW_TWSI(twsi_id)))).s.v)
		;
	twsi_printf("Results:\n");
	cvmx_csr_db_decode(cvmx_get_proc_id(), CVMX_MIO_TWSX_SW_TWSI(twsi_id), sw_twsi_val.u64);

	/* Poll until reads succeed, or polling times out */
	to = 100;
	while (to-- > 0) {
		uint64_t data;
		if (cvmx_twsix_read(twsi_id, dev_addr, 1, &data) >= 0)
			break;
	}
	if (to <= 0)
		return -1;

	return num_bytes;
#endif
}