/* $NetBSD: ns8250_uart.c,v 1.7 2021/01/27 03:10:21 thorpej Exp $ */

/*-
* Copyright (c) 2017-2020 Jared McNeill <[email protected]>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``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 FOUNDATION OR CONTRIBUTORS
* 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.
*/

#include <sys/cdefs.h>

__KERNEL_RCSID(1, "$NetBSD: ns8250_uart.c,v 1.7 2021/01/27 03:10:21 thorpej Exp $");

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/device.h>
#include <sys/intr.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/termios.h>

#include <dev/ic/comvar.h>

#include <dev/fdt/fdtvar.h>

static int ns8250_uart_match(device_t, cfdata_t, void *);
static void ns8250_uart_attach(device_t, device_t, void *);

struct ns8250_config {
       int                     type;
       int                     (*enable)(struct com_softc *);
       void                    (*disable)(struct com_softc *);
};

static const struct ns8250_config ns8250_config = {
       .type = COM_TYPE_NORMAL,
};

static const struct ns8250_config ns16750_config = {
       .type = COM_TYPE_16750,
};

#define NS8250_OCTEON_USR_REG           0x0138

static int
ns8250_octeon_enable(struct com_softc *sc)
{
       struct com_regs *regsp = &sc->sc_regs;

       /* XXX Clear old busy detect interrupts */
       bus_space_read_1(regsp->cr_iot, regsp->cr_ioh, NS8250_OCTEON_USR_REG);

       return 0;
}

static const struct ns8250_config octeon_config = {
       .type = COM_TYPE_16550_NOERS,
       .enable = ns8250_octeon_enable,
};

static const struct device_compatible_entry compat_data[] = {
       { .compat = "cavium,octeon-3860-uart",  .data = &octeon_config },
       { .compat = "ns8250",                   .data = &ns8250_config },
       { .compat = "ns16450",                  .data = &ns8250_config },
       { .compat = "ns16550a",                 .data = &ns8250_config },
       { .compat = "ns16550",                  .data = &ns8250_config },
       { .compat = "ns16750",                  .data = &ns16750_config },
       DEVICE_COMPAT_EOL
};

CFATTACH_DECL_NEW(ns8250_uart, sizeof(struct com_softc),
       ns8250_uart_match, ns8250_uart_attach, NULL, NULL);

static int
ns8250_uart_match(device_t parent, cfdata_t cf, void *aux)
{
       struct fdt_attach_args * const faa = aux;

       return of_compatible_match(faa->faa_phandle, compat_data);
}

static void
ns8250_uart_attach(device_t parent, device_t self, void *aux)
{
       struct com_softc * const sc = device_private(self);
       struct fdt_attach_args * const faa = aux;
       const int phandle = faa->faa_phandle;
       bus_space_tag_t bst = faa->faa_bst;
       bus_space_handle_t bsh;
       char intrstr[128];
       struct clk *clk;
       bus_addr_t addr;
       bus_size_t size;
       u_int reg_shift;
       int error;
       void *ih;

       const struct ns8250_config *config =
           of_compatible_lookup(phandle, compat_data)->data;

       if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
               aprint_error(": couldn't get registers\n");
               return;
       }

       if (of_getprop_uint32(phandle, "reg-shift", &reg_shift)) {
               /* missing or bad reg-shift property, assume 0 */
               reg_shift = 0;
       }

       sc->sc_dev = self;
       if (of_getprop_uint32(phandle, "clock-frequency", &sc->sc_frequency)) {
               clk = fdtbus_clock_get_index(phandle, 0);
               if (clk != NULL)
                       sc->sc_frequency = clk_get_rate(clk);
       }
       if (sc->sc_frequency == 0) {
               aprint_error(": couldn't get frequency\n");
               return;
       }

       sc->sc_type = config->type;
       sc->enable = config->enable;
       sc->disable = config->disable;

       error = bus_space_map(bst, addr, size, 0, &bsh);
       if (error) {
               aprint_error(": couldn't map %#" PRIx64 ": %d",
                   (uint64_t)addr, error);
               return;
       }

       com_init_regs_stride(&sc->sc_regs, bst, bsh, addr, reg_shift);

       if (config->enable != NULL) {
               sc->enable(sc);
               sc->enabled = 1;
       }

       com_attach_subr(sc);

       if (!fdtbus_intr_str(faa->faa_phandle, 0, intrstr, sizeof(intrstr))) {
               aprint_error_dev(self, "failed to decode interrupt\n");
               return;
       }

       ih = fdtbus_intr_establish_xname(faa->faa_phandle, 0, IPL_SERIAL,
           FDT_INTR_MPSAFE, comintr, sc, device_xname(self));
       if (ih == NULL) {
               aprint_error_dev(self, "failed to establish interrupt on %s\n",
                   intrstr);
               return;
       }
       aprint_normal_dev(self, "interrupting on %s\n", intrstr);
}

/*
* Console support
*/

static int
ns8250_uart_console_match(int phandle)
{
       return of_compatible_match(phandle, compat_data);
}

static void
ns8250_uart_console_consinit(struct fdt_attach_args *faa, u_int uart_freq)
{
       const int phandle = faa->faa_phandle;
       bus_space_tag_t bst = faa->faa_bst;
       bus_space_handle_t dummy_bsh;
       struct com_regs regs;
       bus_addr_t addr;
       tcflag_t flags;
       u_int reg_shift;
       int speed;

       const struct ns8250_config *config =
           of_compatible_lookup(phandle, compat_data)->data;

       fdtbus_get_reg(phandle, 0, &addr, NULL);
       speed = fdtbus_get_stdout_speed();
       if (speed < 0)
               speed = 115200; /* default */
       flags = fdtbus_get_stdout_flags();

       if (of_getprop_uint32(phandle, "reg-shift", &reg_shift)) {
               /* missing or bad reg-shift property, assume 0 */
               reg_shift = 0;
       }

       memset(&dummy_bsh, 0, sizeof(dummy_bsh));
       com_init_regs_stride(&regs, bst, dummy_bsh, addr, reg_shift);

       if (comcnattach1(&regs, speed, uart_freq, config->type, flags))
               panic("Cannot initialize ns8250 console");
}

static const struct fdt_console ns8250_uart_console = {
       .match = ns8250_uart_console_match,
       .consinit = ns8250_uart_console_consinit,
};

FDT_CONSOLE(ns8250_uart, &ns8250_uart_console);