/*
 * (C) Copyright 2002
 * Rich Ireland, Enterasys Networks, rireland@enterasys.com.
 * Keith Outwater, keith_outwater@mvis.com
 *
 * SPDX-License-Identifier:     GPL-2.0+
 */

/*
 * Configuration support for Xilinx Virtex2 devices.  Based
 * on spartan2.c (Rich Ireland, rireland@enterasys.com).
 */

#include <common.h>
#include <console.h>
#include <virtex2.h>

#if 0
#define FPGA_DEBUG
#endif

#ifdef  FPGA_DEBUG
#define PRINTF(fmt,args...)     printf (fmt ,##args)
#else
#define PRINTF(fmt,args...)
#endif

/*
 * If the SelectMap interface can be overrun by the processor, define
 * CONFIG_SYS_FPGA_CHECK_BUSY and/or CONFIG_FPGA_DELAY in the board configuration
 * file and add board-specific support for checking BUSY status. By default,
 * assume that the SelectMap interface cannot be overrun.
 */
#ifndef CONFIG_SYS_FPGA_CHECK_BUSY
#undef CONFIG_SYS_FPGA_CHECK_BUSY
#endif

#ifndef CONFIG_FPGA_DELAY
#define CONFIG_FPGA_DELAY()
#endif

#ifndef CONFIG_SYS_FPGA_PROG_FEEDBACK
#define CONFIG_SYS_FPGA_PROG_FEEDBACK
#endif

/*
 * Don't allow config cycle to be interrupted
 */
#ifndef CONFIG_SYS_FPGA_CHECK_CTRLC
#undef CONFIG_SYS_FPGA_CHECK_CTRLC
#endif

/*
 * Check for errors during configuration by default
 */
#ifndef CONFIG_SYS_FPGA_CHECK_ERROR
#define CONFIG_SYS_FPGA_CHECK_ERROR
#endif

/*
 * The default timeout in mS for INIT_B to deassert after PROG_B has
 * been deasserted. Per the latest Virtex II Handbook (page 347), the
 * max time from PORG_B deassertion to INIT_B deassertion is 4uS per
 * data frame for the XC2V8000.  The XC2V8000 has 2860 data frames
 * which yields 11.44 mS.  So let's make it bigger in order to handle
 * an XC2V1000, if anyone can ever get ahold of one.
 */
#ifndef CONFIG_SYS_FPGA_WAIT_INIT
#define CONFIG_SYS_FPGA_WAIT_INIT       CONFIG_SYS_HZ/2 /* 500 ms */
#endif

/*
 * The default timeout for waiting for BUSY to deassert during configuration.
 * This is normally not necessary since for most reasonable configuration
 * clock frequencies (i.e. 66 MHz or less), BUSY monitoring is unnecessary.
 */
#ifndef CONFIG_SYS_FPGA_WAIT_BUSY
#define CONFIG_SYS_FPGA_WAIT_BUSY       CONFIG_SYS_HZ/200       /* 5 ms*/
#endif

/* Default timeout for waiting for FPGA to enter operational mode after
 * configuration data has been written.
 */
#ifndef CONFIG_SYS_FPGA_WAIT_CONFIG
#define CONFIG_SYS_FPGA_WAIT_CONFIG     CONFIG_SYS_HZ/5 /* 200 ms */
#endif

static int virtex2_ssm_load(xilinx_desc *desc, const void *buf, size_t bsize);
static int virtex2_ssm_dump(xilinx_desc *desc, const void *buf, size_t bsize);

static int virtex2_ss_load(xilinx_desc *desc, const void *buf, size_t bsize);
static int virtex2_ss_dump(xilinx_desc *desc, const void *buf, size_t bsize);

static int virtex2_load(xilinx_desc *desc, const void *buf, size_t bsize,
                        bitstream_type bstype)
{
        int ret_val = FPGA_FAIL;

        switch (desc->iface) {
        case slave_serial:
                PRINTF ("%s: Launching Slave Serial Load\n", __FUNCTION__);
                ret_val = virtex2_ss_load(desc, buf, bsize);
                break;

        case slave_selectmap:
                PRINTF ("%s: Launching Slave Parallel Load\n", __FUNCTION__);
                ret_val = virtex2_ssm_load(desc, buf, bsize);
                break;

        default:
                printf ("%s: Unsupported interface type, %d\n",
                                __FUNCTION__, desc->iface);
        }
        return ret_val;
}

static int virtex2_dump(xilinx_desc *desc, const void *buf, size_t bsize)
{
        int ret_val = FPGA_FAIL;

        switch (desc->iface) {
        case slave_serial:
                PRINTF ("%s: Launching Slave Serial Dump\n", __FUNCTION__);
                ret_val = virtex2_ss_dump(desc, buf, bsize);
                break;

        case slave_parallel:
                PRINTF ("%s: Launching Slave Parallel Dump\n", __FUNCTION__);
                ret_val = virtex2_ssm_dump(desc, buf, bsize);
                break;

        default:
                printf ("%s: Unsupported interface type, %d\n",
                                __FUNCTION__, desc->iface);
        }
        return ret_val;
}

static int virtex2_info(xilinx_desc *desc)
{
        return FPGA_SUCCESS;
}

/*
 * Virtex-II Slave SelectMap configuration loader. Configuration via
 * SelectMap is as follows:
 * 1. Set the FPGA's PROG_B line low.
 * 2. Set the FPGA's PROG_B line high.  Wait for INIT_B to go high.
 * 3. Write data to the SelectMap port.  If INIT_B goes low at any time
 *    this process, a configuration error (most likely CRC failure) has
 *    ocurred.  At this point a status word may be read from the
 *    SelectMap interface to determine the source of the problem (You
 *    could, for instance, put this in your 'abort' function handler).
 * 4. After all data has been written, test the state of the FPGA
 *    INIT_B and DONE lines.  If both are high, configuration has
 *    succeeded. Congratulations!
 */
static int virtex2_ssm_load(xilinx_desc *desc, const void *buf, size_t bsize)
{
        int ret_val = FPGA_FAIL;
        xilinx_virtex2_slave_selectmap_fns *fn = desc->iface_fns;

        PRINTF ("%s:%d: Start with interface functions @ 0x%p\n",
                        __FUNCTION__, __LINE__, fn);

        if (fn) {
                size_t bytecount = 0;
                unsigned char *data = (unsigned char *) buf;
                int cookie = desc->cookie;
                unsigned long ts;

                /* Gotta split this one up (so the stack won't blow??) */
                PRINTF ("%s:%d: Function Table:\n"
                                "  base   0x%p\n"
                                "  struct 0x%p\n"
                                "  pre    0x%p\n"
                                "  prog   0x%p\n"
                                "  init   0x%p\n"
                                "  error  0x%p\n",
                                __FUNCTION__, __LINE__,
                                &fn, fn, fn->pre, fn->pgm, fn->init, fn->err);
                PRINTF ("  clock  0x%p\n"
                                "  cs     0x%p\n"
                                "  write  0x%p\n"
                                "  rdata  0x%p\n"
                                "  wdata  0x%p\n"
                                "  busy   0x%p\n"
                                "  abort  0x%p\n"
                                "  post   0x%p\n\n",
                                fn->clk, fn->cs, fn->wr, fn->rdata, fn->wdata,
                                fn->busy, fn->abort, fn->post);

#ifdef CONFIG_SYS_FPGA_PROG_FEEDBACK
                printf ("Initializing FPGA Device %d...\n", cookie);
#endif
                /*
                 * Run the pre configuration function if there is one.
                 */
                if (*fn->pre) {
                        (*fn->pre) (cookie);
                }

                /*
                 * Assert the program line.  The minimum pulse width for
                 * Virtex II devices is 300 nS (Tprogram parameter in datasheet).
                 * There is no maximum value for the pulse width.  Check to make
                 * sure that INIT_B goes low after assertion of PROG_B
                 */
                (*fn->pgm) (true, true, cookie);
                udelay (10);
                ts = get_timer (0);
                do {
                        if (get_timer (ts) > CONFIG_SYS_FPGA_WAIT_INIT) {
                                printf ("%s:%d: ** Timeout after %d ticks waiting for INIT"
                                                " to assert.\n", __FUNCTION__, __LINE__,
                                                CONFIG_SYS_FPGA_WAIT_INIT);
                                (*fn->abort) (cookie);
                                return FPGA_FAIL;
                        }
                } while (!(*fn->init) (cookie));

                (*fn->pgm) (false, true, cookie);
                CONFIG_FPGA_DELAY ();
                (*fn->clk) (true, true, cookie);

                /*
                 * Start a timer and wait for INIT_B to go high
                 */
                ts = get_timer (0);
                do {
                        CONFIG_FPGA_DELAY ();
                        if (get_timer (ts) > CONFIG_SYS_FPGA_WAIT_INIT) {
                                printf ("%s:%d: ** Timeout after %d ticks waiting for INIT"
                                                " to deassert.\n", __FUNCTION__, __LINE__,
                                                CONFIG_SYS_FPGA_WAIT_INIT);
                                (*fn->abort) (cookie);
                                return FPGA_FAIL;
                        }
                } while ((*fn->init) (cookie) && (*fn->busy) (cookie));

                (*fn->wr) (true, true, cookie);
                (*fn->cs) (true, true, cookie);

                udelay (10000);

                /*
                 * Load the data byte by byte
                 */
                while (bytecount < bsize) {
#ifdef CONFIG_SYS_FPGA_CHECK_CTRLC
                        if (ctrlc ()) {
                                (*fn->abort) (cookie);
                                return FPGA_FAIL;
                        }
#endif

                        if ((*fn->done) (cookie) == FPGA_SUCCESS) {
                            PRINTF ("%s:%d:done went active early, bytecount = %d\n",
                                    __FUNCTION__, __LINE__, bytecount);
                            break;
                        }

#ifdef CONFIG_SYS_FPGA_CHECK_ERROR
                        if ((*fn->init) (cookie)) {
                                printf ("\n%s:%d:  ** Error: INIT asserted during"
                                                " configuration\n", __FUNCTION__, __LINE__);
                                printf ("%d = buffer offset, %d = buffer size\n",
                                        bytecount, bsize);
                                (*fn->abort) (cookie);
                                return FPGA_FAIL;
                        }
#endif

                        (*fn->wdata) (data[bytecount++], true, cookie);
                        CONFIG_FPGA_DELAY ();

                        /*
                         * Cycle the clock pin
                         */
                        (*fn->clk) (false, true, cookie);
                        CONFIG_FPGA_DELAY ();
                        (*fn->clk) (true, true, cookie);

#ifdef CONFIG_SYS_FPGA_CHECK_BUSY
                        ts = get_timer (0);
                        while ((*fn->busy) (cookie)) {
                                if (get_timer (ts) > CONFIG_SYS_FPGA_WAIT_BUSY) {
                                        printf ("%s:%d: ** Timeout after %d ticks waiting for"
                                                        " BUSY to deassert\n",
                                                        __FUNCTION__, __LINE__, CONFIG_SYS_FPGA_WAIT_BUSY);
                                        (*fn->abort) (cookie);
                                        return FPGA_FAIL;
                                }
                        }
#endif

#ifdef CONFIG_SYS_FPGA_PROG_FEEDBACK
                        if (bytecount % (bsize / 40) == 0)
                                putc ('.');
#endif
                }

                /*
                 * Finished writing the data; deassert FPGA CS_B and WRITE_B signals.
                 */
                CONFIG_FPGA_DELAY ();
                (*fn->cs) (false, true, cookie);
                (*fn->wr) (false, true, cookie);

#ifdef CONFIG_SYS_FPGA_PROG_FEEDBACK
                putc ('\n');
#endif

                /*
                 * Check for successful configuration.  FPGA INIT_B and DONE should
                 * both be high upon successful configuration.
                 */
                ts = get_timer (0);
                ret_val = FPGA_SUCCESS;
                while (((*fn->done) (cookie) == FPGA_FAIL) || (*fn->init) (cookie)) {
                        if (get_timer (ts) > CONFIG_SYS_FPGA_WAIT_CONFIG) {
                                printf ("%s:%d: ** Timeout after %d ticks waiting for DONE to"
                                                "assert and INIT to deassert\n",
                                                __FUNCTION__, __LINE__, CONFIG_SYS_FPGA_WAIT_CONFIG);
                                (*fn->abort) (cookie);
                                ret_val = FPGA_FAIL;
                                break;
                        }
                }

                if (ret_val == FPGA_SUCCESS) {
#ifdef CONFIG_SYS_FPGA_PROG_FEEDBACK
                        printf ("Initialization of FPGA device %d complete\n", cookie);
#endif
                        /*
                         * Run the post configuration function if there is one.
                         */
                        if (*fn->post) {
                                (*fn->post) (cookie);
                        }
                } else {
#ifdef CONFIG_SYS_FPGA_PROG_FEEDBACK
                        printf ("** Initialization of FPGA device %d FAILED\n",
                                        cookie);
#endif
                }
        } else {
                printf ("%s:%d: NULL Interface function table!\n",
                                __FUNCTION__, __LINE__);
        }
        return ret_val;
}

/*
 * Read the FPGA configuration data
 */
static int virtex2_ssm_dump(xilinx_desc *desc, const void *buf, size_t bsize)
{
        int ret_val = FPGA_FAIL;
        xilinx_virtex2_slave_selectmap_fns *fn = desc->iface_fns;

        if (fn) {
                unsigned char *data = (unsigned char *) buf;
                size_t bytecount = 0;
                int cookie = desc->cookie;

                printf ("Starting Dump of FPGA Device %d...\n", cookie);

                (*fn->cs) (true, true, cookie);
                (*fn->clk) (true, true, cookie);

                while (bytecount < bsize) {
#ifdef CONFIG_SYS_FPGA_CHECK_CTRLC
                        if (ctrlc ()) {
                                (*fn->abort) (cookie);
                                return FPGA_FAIL;
                        }
#endif
                        /*
                         * Cycle the clock and read the data
                         */
                        (*fn->clk) (false, true, cookie);
                        (*fn->clk) (true, true, cookie);
                        (*fn->rdata) (&(data[bytecount++]), cookie);
#ifdef CONFIG_SYS_FPGA_PROG_FEEDBACK
                        if (bytecount % (bsize / 40) == 0)
                                putc ('.');
#endif
                }

                /*
                 * Deassert CS_B and cycle the clock to deselect the device.
                 */
                (*fn->cs) (false, false, cookie);
                (*fn->clk) (false, true, cookie);
                (*fn->clk) (true, true, cookie);

#ifdef CONFIG_SYS_FPGA_PROG_FEEDBACK
                putc ('\n');
#endif
                puts ("Done.\n");
        } else {
                printf ("%s:%d: NULL Interface function table!\n",
                                __FUNCTION__, __LINE__);
        }
        return ret_val;
}

static int virtex2_ss_load(xilinx_desc *desc, const void *buf, size_t bsize)
{
        printf ("%s: Slave Serial Loading is unsupported\n", __FUNCTION__);
        return FPGA_FAIL;
}

static int virtex2_ss_dump(xilinx_desc *desc, const void *buf, size_t bsize)
{
        printf ("%s: Slave Serial Dumping is unsupported\n", __FUNCTION__);
        return FPGA_FAIL;
}

/* vim: set ts=4 tw=78: */

struct xilinx_fpga_op virtex2_op = {
        .load = virtex2_load,
        .dump = virtex2_dump,
        .info = virtex2_info,
};