path: root/drivers/staging/octeon/cvmx-spi.c

/***********************license start***************
 * Author: Cavium Networks
 *
 * Contact: support@caviumnetworks.com
 * This file is part of the OCTEON SDK
 *
 * Copyright (c) 2003-2008 Cavium Networks
 *
 * This file is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, Version 2, as
 * published by the Free Software Foundation.
 *
 * This file is distributed in the hope that it will be useful, but
 * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
 * NONINFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this file; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 * or visit http://www.gnu.org/licenses/.
 *
 * This file may also be available under a different license from Cavium.
 * Contact Cavium Networks for more information
 ***********************license end**************************************/

/*
 *
 * Support library for the SPI
 */
#include <asm/octeon/octeon.h>

#include "cvmx-config.h"

#include "cvmx-pko.h"
#include "cvmx-spi.h"

#include "cvmx-spxx-defs.h"
#include "cvmx-stxx-defs.h"
#include "cvmx-srxx-defs.h"

#define INVOKE_CB(function_p, args...)		\
	do {					\
		if (function_p) {		\
			res = function_p(args); \
			if (res)		\
				return res;	\
		}				\
	} while (0)

#if CVMX_ENABLE_DEBUG_PRINTS
static const char *modes[] =
    { "UNKNOWN", "TX Halfplex", "Rx Halfplex", "Duplex" };
#endif

/* Default callbacks, can be overridden
 *  using cvmx_spi_get_callbacks/cvmx_spi_set_callbacks
 */
static cvmx_spi_callbacks_t cvmx_spi_callbacks = {
	.reset_cb = cvmx_spi_reset_cb,
	.calendar_setup_cb = cvmx_spi_calendar_setup_cb,
	.clock_detect_cb = cvmx_spi_clock_detect_cb,
	.training_cb = cvmx_spi_training_cb,
	.calendar_sync_cb = cvmx_spi_calendar_sync_cb,
	.interface_up_cb = cvmx_spi_interface_up_cb
};

/**
 * Get current SPI4 initialization callbacks
 *
 * @callbacks:  Pointer to the callbacks structure.to fill
 *
 * Returns Pointer to cvmx_spi_callbacks_t structure.
 */
void cvmx_spi_get_callbacks(cvmx_spi_callbacks_t *callbacks)
{
	memcpy(callbacks, &cvmx_spi_callbacks, sizeof(cvmx_spi_callbacks));
}

/**
 * Set new SPI4 initialization callbacks
 *
 * @new_callbacks:  Pointer to an updated callbacks structure.
 */
void cvmx_spi_set_callbacks(cvmx_spi_callbacks_t *new_callbacks)
{
	memcpy(&cvmx_spi_callbacks, new_callbacks, sizeof(cvmx_spi_callbacks));
}

/**
 * Initialize and start the SPI interface.
 *
 * @interface: The identifier of the packet interface to configure and
 *                  use as a SPI interface.
 * @mode:      The operating mode for the SPI interface. The interface
 *                  can operate as a full duplex (both Tx and Rx data paths
 *                  active) or as a halfplex (either the Tx data path is
 *                  active or the Rx data path is active, but not both).
 * @timeout:   Timeout to wait for clock synchronization in seconds
 * @num_ports: Number of SPI ports to configure
 *
 * Returns Zero on success, negative of failure.
 */
int cvmx_spi_start_interface(int interface, cvmx_spi_mode_t mode, int timeout,
			     int num_ports)
{
	int res = -1;

	if (!(OCTEON_IS_MODEL(OCTEON_CN38XX) || OCTEON_IS_MODEL(OCTEON_CN58XX)))
		return res;

	/* Callback to perform SPI4 reset */
	INVOKE_CB(cvmx_spi_callbacks.reset_cb, interface, mode);

	/* Callback to perform calendar setup */
	INVOKE_CB(cvmx_spi_callbacks.calendar_setup_cb, interface, mode,
		  num_ports);

	/* Callback to perform clock detection */
	INVOKE_CB(cvmx_spi_callbacks.clock_detect_cb, interface, mode, timeout);

	/* Callback to perform SPI4 link training */
	INVOKE_CB(cvmx_spi_callbacks.training_cb, interface, mode, timeout);

	/* Callback to perform calendar sync */
	INVOKE_CB(cvmx_spi_callbacks.calendar_sync_cb, interface, mode,
		  timeout);

	/* Callback to handle interface coming up */
	INVOKE_CB(cvmx_spi_callbacks.interface_up_cb, interface, mode);

	return res;
}

/**
 * This routine restarts the SPI interface after it has lost synchronization
 * with its correspondent system.
 *
 * @interface: The identifier of the packet interface to configure and
 *                  use as a SPI interface.
 * @mode:      The operating mode for the SPI interface. The interface
 *                  can operate as a full duplex (both Tx and Rx data paths
 *                  active) or as a halfplex (either the Tx data path is
 *                  active or the Rx data path is active, but not both).
 * @timeout:   Timeout to wait for clock synchronization in seconds
 *
 * Returns Zero on success, negative of failure.
 */
int cvmx_spi_restart_interface(int interface, cvmx_spi_mode_t mode, int timeout)
{
	int res = -1;

	if (!(OCTEON_IS_MODEL(OCTEON_CN38XX) || OCTEON_IS_MODEL(OCTEON_CN58XX)))
		return res;

	cvmx_dprintf("SPI%d: Restart %s\n", interface, modes[mode]);

	/* Callback to perform SPI4 reset */
	INVOKE_CB(cvmx_spi_callbacks.reset_cb, interface, mode);

	/* NOTE: Calendar setup is not performed during restart */
	/*       Refer to cvmx_spi_start_interface() for the full sequence */

	/* Callback to perform clock detection */
	INVOKE_CB(cvmx_spi_callbacks.clock_detect_cb, interface, mode, timeout);

	/* Callback to perform SPI4 link training */
	INVOKE_CB(cvmx_spi_callbacks.training_cb, interface, mode, timeout);

	/* Callback to perform calendar sync */
	INVOKE_CB(cvmx_spi_callbacks.calendar_sync_cb, interface, mode,
		  timeout);

	/* Callback to handle interface coming up */
	INVOKE_CB(cvmx_spi_callbacks.interface_up_cb, interface, mode);

	return res;
}

/**
 * Callback to perform SPI4 reset
 *
 * @interface: The identifier of the packet interface to configure and
 *                  use as a SPI interface.
 * @mode:      The operating mode for the SPI interface. The interface
 *                  can operate as a full duplex (both Tx and Rx data paths
 *                  active) or as a halfplex (either the Tx data path is
 *                  active or the Rx data path is active, but not both).
 *
 * Returns Zero on success, non-zero error code on failure (will cause
 * SPI initialization to abort)
 */
int cvmx_spi_reset_cb(int interface, cvmx_spi_mode_t mode)
{
	union cvmx_spxx_dbg_deskew_ctl spxx_dbg_deskew_ctl;
	union cvmx_spxx_clk_ctl spxx_clk_ctl;
	union cvmx_spxx_bist_stat spxx_bist_stat;
	union cvmx_spxx_int_msk spxx_int_msk;
	union cvmx_stxx_int_msk stxx_int_msk;
	union cvmx_spxx_trn4_ctl spxx_trn4_ctl;
	int index;
	uint64_t MS = cvmx_sysinfo_get()->cpu_clock_hz / 1000;

	/* Disable SPI error events while we run BIST */
	spxx_int_msk.u64 = cvmx_read_csr(CVMX_SPXX_INT_MSK(interface));
	cvmx_write_csr(CVMX_SPXX_INT_MSK(interface), 0);
	stxx_int_msk.u64 = cvmx_read_csr(CVMX_STXX_INT_MSK(interface));
	cvmx_write_csr(CVMX_STXX_INT_MSK(interface), 0);

	/* Run BIST in the SPI interface */
	cvmx_write_csr(CVMX_SRXX_COM_CTL(interface), 0);
	cvmx_write_csr(CVMX_STXX_COM_CTL(interface), 0);
	spxx_clk_ctl.u64 = 0;
	spxx_clk_ctl.s.runbist = 1;
	cvmx_write_csr(CVMX_SPXX_CLK_CTL(interface), spxx_clk_ctl.u64);
	cvmx_wait(10 * MS);
	spxx_bist_stat.u64 = cvmx_read_csr(CVMX_SPXX_BIST_STAT(interface));
	if (spxx_bist_stat.s.stat0)
		cvmx_dprintf
		    ("ERROR SPI%d: BIST failed on receive datapath FIFO\n",
		     interface);
	if (spxx_bist_stat.s.stat1)
		cvmx_dprintf("ERROR SPI%d: BIST failed on RX calendar table\n",
			     interface);
	if (spxx_bist_stat.s.stat2)
		cvmx_dprintf("ERROR SPI%d: BIST failed on TX calendar table\n",
			     interface);

	/* Clear the calendar table after BIST to fix parity errors */
	for (index = 0; index < 32; index++) {
		union cvmx_srxx_spi4_calx srxx_spi4_calx;
		union cvmx_stxx_spi4_calx stxx_spi4_calx;

		srxx_spi4_calx.u64 = 0;
		srxx_spi4_calx.s.oddpar = 1;
		cvmx_write_csr(CVMX_SRXX_SPI4_CALX(index, interface),
			       srxx_spi4_calx.u64);

		stxx_spi4_calx.u64 = 0;
		stxx_spi4_calx.s.oddpar = 1;
		cvmx_write_csr(CVMX_STXX_SPI4_CALX(index, interface),
			       stxx_spi4_calx.u64);
	}

	/* Re enable reporting of error interrupts */
	cvmx_write_csr(CVMX_SPXX_INT_REG(interface),
		       cvmx_read_csr(CVMX_SPXX_INT_REG(interface)));
	cvmx_write_csr(CVMX_SPXX_INT_MSK(interface), spxx_int_msk.u64);
	cvmx_write_csr(CVMX_STXX_INT_REG(interface),
		       cvmx_read_csr(CVMX_STXX_INT_REG(interface)));
	cvmx_write_csr(CVMX_STXX_INT_MSK(interface), stxx_int_msk.u64);

	/* Setup the CLKDLY right in the middle */
	spxx_clk_ctl.u64 = 0;
	spxx_clk_ctl.s.seetrn = 0;
	spxx_clk_ctl.s.clkdly = 0x10;
	spxx_clk_ctl.s.runbist = 0;
	spxx_clk_ctl.s.statdrv = 0;
	/* This should always be on the opposite edge as statdrv */
	spxx_clk_ctl.s.statrcv = 1;
	spxx_clk_ctl.s.sndtrn = 0;
	spxx_clk_ctl.s.drpt