/*
 * Copyright (c) 2009 Vineeth Pillai
 * Copyright (c) 2014 Jiri Svoboda
 * 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @file
 */

#include <assert.h>
#include <bitops.h>
#include <stdio.h>
#include <errno.h>
#include <ddf/driver.h>
#include <ddf/interrupt.h>
#include <ddf/log.h>
#include <device/hw_res.h>
#include <device/hw_res_parsed.h>
#include <io/chardev_srv.h>

#include "pl050_hw.h"

#define NAME "pl050"

enum {
	buffer_size = 64
};

static int pl050_dev_add(ddf_dev_t *);
static int pl050_fun_online(ddf_fun_t *);
static int pl050_fun_offline(ddf_fun_t *);
static void pl050_char_conn(ipc_callid_t, ipc_call_t *, void *);
static int pl050_read(chardev_srv_t *, void *, size_t, size_t *);
static int pl050_write(chardev_srv_t *, const void *, size_t, size_t *);

static driver_ops_t driver_ops = {
	.dev_add = &pl050_dev_add,
	.fun_online = &pl050_fun_online,
	.fun_offline = &pl050_fun_offline
};

static driver_t pl050_driver = {
	.name = NAME,
	.driver_ops = &driver_ops
};

static chardev_ops_t pl050_chardev_ops = {
	.read = pl050_read,
	.write = pl050_write
};

typedef struct {
	async_sess_t *parent_sess;
	ddf_dev_t *dev;
	char *name;

	ddf_fun_t *fun_a;
	chardev_srvs_t cds;

	uintptr_t iobase;
	size_t iosize;
	kmi_regs_t *regs;
	uint8_t buffer[buffer_size];
	size_t buf_rp;
	size_t buf_wp;
	fibril_condvar_t buf_cv;
	fibril_mutex_t buf_lock;
} pl050_t;

static irq_pio_range_t pl050_ranges[] = {
	{
		.base = 0,
		.size = 9,
	}
};

static irq_cmd_t pl050_cmds[] = {
	{
		.cmd = CMD_PIO_READ_8,
		.addr = NULL,
		.dstarg = 1
	},
	{
		.cmd = CMD_AND,
		.value = BIT_V(uint8_t, kmi_stat_rxfull),
		.srcarg = 1,
		.dstarg = 3
	},
	{
		.cmd = CMD_PREDICATE,
		.value = 2,
		.srcarg = 3
	},
	{
		.cmd = CMD_PIO_READ_8,
		.addr = NULL,  /* Will be patched in run-time */
		.dstarg = 2
	},
	{
		.cmd = CMD_ACCEPT
	}
};

static irq_code_t pl050_irq_code = {
	sizeof(pl050_ranges) / sizeof(irq_pio_range_t),
	pl050_ranges,
	sizeof(pl050_cmds) / sizeof(irq_cmd_t),
	pl050_cmds
};

static pl050_t *pl050_from_fun(ddf_fun_t *fun)
{
	return (pl050_t *)ddf_dev_data_get(ddf_fun_get_dev(fun));
}

static void pl050_interrupt(ipc_callid_t iid, ipc_call_t *call, ddf_dev_t *dev)
{
	pl050_t *pl050 = (pl050_t *)ddf_dev_data_get(dev);
	size_t nidx;

	fibril_mutex_lock(&pl050->buf_lock);
	nidx = (pl050->buf_wp + 1) % buffer_size;
	if (nidx == pl050->buf_rp) {
		/** Buffer overrunt */
		ddf_msg(LVL_WARN, "Buffer overrun.");
		fibril_mutex_unlock(&pl050->buf_lock);
		return;
	}

	pl050->buffer[pl050->buf_wp] = IPC_GET_ARG2(*call);
	pl050->buf_wp = nidx;
	fibril_condvar_broadcast(&pl050->buf_cv);
	fibril_mutex_unlock(&pl050->buf_lock);
}

static int pl050_init(pl050_t *pl050)
{
	hw_res_list_parsed_t res;
	void *regs;
	int rc;

	fibril_mutex_initialize(&pl050->buf_lock);
	fibril_condvar_initialize(&pl050->buf_cv);
	pl050->buf_rp = pl050->buf_wp = 0;

	pl050->parent_sess = ddf_dev_parent_sess_get(pl050->dev);
	if (pl050->parent_sess == NULL) {
		ddf_msg(LVL_ERROR, "Failed connecitng parent driver.");
		rc = ENOMEM;
		goto error;
	}

	hw_res_list_parsed_init(&res);
	rc = hw_res_get_list_parsed(pl050->parent_sess, &res, 0);
	if (rc != EOK) {
		ddf_msg(LVL_ERROR, "Failed getting resource list.");
		goto error;
	}

	if (res.mem_ranges.count != 1) {
		ddf_msg(LVL_ERROR, "Expected exactly one memory range.");
		rc = EINVAL;
		goto error;
	}

	pl050->iobase = RNGABS(res.mem_ranges.ranges[0]);
	pl050->iosize = RNGSZ(res.mem_ranges.ranges[0]);

	pl050_irq_code.ranges[0].base = pl050->iobase;
	kmi_regs_t *regsphys = (kmi_regs_t *) pl050->iobase;
	pl050_irq_code.cmds[0].addr = &regsphys->stat;
	pl050_irq_code.cmds[3].addr = &regsphys->data;

	if (res.irqs.count != 1) {
		ddf_msg(LVL_ERROR, "Expected exactly one IRQ.");
		rc = EINVAL;
		goto error;
	}

	ddf_msg(LVL_DEBUG, "iobase=%p irq=%d", (void *)pl050->iobase,
	    res.irqs.irqs[0]);

	rc = pio_enable((void *)pl050->iobase, sizeof(kmi_regs_t), &regs);
	if (rc != EOK) {
		ddf_msg(LVL_ERROR, "Error enabling PIO");
		goto error;
	}

	pl050->regs = regs;

	const int irq_cap = register_interrupt_handler(pl050->dev,
	    res.irqs.irqs[0], pl050_interrupt, &pl050_irq_code);
	if (irq_cap < 0) {
		rc = irq_cap;
		ddf_msg(LVL_ERROR, "Failed registering interrupt handler. (%d)",
		    rc);
		goto error;
	}

	rc = hw_res_enable_interrupt(pl050->parent_sess, res.irqs.irqs[0]);
	if (rc != EOK) {
		ddf_msg(LVL_ERROR, "Failed enabling interrupt. (%d)", rc);
		goto error;
	}

	pio_write_8(&pl050->regs->cr,
	    BIT_V(uint8_t, kmi_cr_enable) |
	    BIT_V(uint8_t, kmi_cr_rxintr));

	return EOK;
error:
	return rc;
}

static int pl050_read(chardev_srv_t *srv, void *buffer, size_t size,
    size_t *nread)
{
	pl050_t *pl050 = (pl050_t *)srv->srvs->sarg;
	uint8_t *bp = buffer;
	size_t left;

	fibril_mutex_lock(&pl050->buf_lock);

	left = size;
	while (left > 0) {
		while (left == size && pl050->buf_rp == pl050->buf_wp)
			fibril_condvar_wait(&pl050->buf_cv, &pl050->buf_lock);
		if (pl050->buf_rp == pl050->buf_wp)
			break;
		*bp++ = pl050->buffer[pl050->buf_rp];
		--left;
		pl050->buf_rp = (pl050->buf_rp + 1) % buffer_size;
	}

	fibril_mutex_unlock(&pl050->buf_lock);

	*nread = size - left;
	return EOK;
}

static int pl050_write(chardev_srv_t *srv, const void *data, size_t size,
    size_t *nwritten)
{
	pl050_t *pl050 = (pl050_t *)srv->srvs->sarg;
	uint8_t *dp = (uint8_t *)data;
	uint8_t status;
	size_t i;

	ddf_msg(LVL_NOTE, "%s/pl050_write(%zu bytes)", pl050->name, size);
	for (i = 0; i < size; i++) {
		while (true) {
			status = pio_read_8(&pl050->regs->stat);
			if ((status & BIT_V(uint8_t, kmi_stat_txempty)) != 0)
				break;
		}
		pio_write_8(&pl050->regs->data, dp[i]);
	}
	ddf_msg(LVL_NOTE, "%s/pl050_write() success", pl050->name);

	*nwritten = size;
	return EOK;
}

void pl050_char_conn(ipc_callid_t iid, ipc_call_t *icall, void *arg)
{
	pl050_t *pl050 = pl050_from_fun((ddf_fun_t *)arg);

	chardev_conn(iid, icall, &pl050->cds);
}

/** Add device. */
static int pl050_dev_add(ddf_dev_t *dev)
{
	ddf_fun_t *fun_a;
	pl050_t *pl050 = NULL;
	const char *mname;
	int rc;

	ddf_msg(LVL_DEBUG, "pl050_dev_add()");

	pl050 = ddf_dev_data_alloc(dev, sizeof(pl050_t));
	if (pl050 == NULL) {
		ddf_msg(LVL_ERROR, "Failed allocating soft state.\n");
		rc = ENOMEM;
		goto error;
	}

	pl050->name = (char *)ddf_dev_get_name(dev);
	if (pl050->name == NULL) {
		rc = ENOMEM;
		goto error;
	}

	fun_a = ddf_fun_create(dev, fun_inner, "a");
	if (fun_a == NULL) {
		ddf_msg(LVL_ERROR, "Failed creating function 'a'.");
		rc = ENOMEM;
		goto error;
	}

	pl050->fun_a = fun_a;
	pl050->dev = dev;

	rc = pl050_init(pl050);
	if (rc != EOK)
		goto error;

	if (str_cmp(pl050->name, "kbd") == 0)
		mname = "char/atkbd";
	else
		mname = "char/ps2mouse";

	rc = ddf_fun_add_match_id(fun_a, mname, 10);
	if (rc != EOK) {
		ddf_msg(LVL_ERROR, "Failed adding match IDs to function %s",
		    "char/xtkbd");
		goto error;
	}

	chardev_srvs_init(&pl050->cds);
	pl050->cds.ops = &pl050_chardev_ops;
	pl050->cds.sarg = pl050;

	ddf_fun_set_conn_handler(fun_a, pl050_char_conn);

	rc = ddf_fun_bind(fun_a);
	if (rc != EOK) {
		ddf_msg(LVL_ERROR, "Failed binding function 'a'. (%d)", rc);
		ddf_fun_destroy(fun_a);
		goto error;
	}

	ddf_msg(LVL_DEBUG, "Device added.");
	return EOK;
error:
	if (pl050 != NULL)
		free(pl050->name);
	return rc;
}

static int pl050_fun_online(ddf_fun_t *fun)
{
	ddf_msg(LVL_DEBUG, "pl050_fun_online()");
	return ddf_fun_online(fun);
}

static int pl050_fun_offline(ddf_fun_t *fun)
{
	ddf_msg(LVL_DEBUG, "pl050_fun_offline()");
	return ddf_fun_offline(fun);
}

int main(int argc, char *argv[])
{
	int rc;

	printf(NAME ": HelenOS pl050 serial device driver\n");
	rc = ddf_log_init(NAME);
	if (rc != EOK) {
		printf(NAME ": Error connecting logging service.");
		return 1;
	}

	return ddf_driver_main(&pl050_driver);
}