/*
 * (C) Copyright 2003 Motorola Inc.
 * Xianghua Xiao (X.Xiao@motorola.com)
 * Modified based on 8260 for 8560.
 *
 * (C) Copyright 2000
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * SPDX-License-Identifier:     GPL-2.0+
 *
 * Hacked for MPC8260 by Murray.Jensen@cmst.csiro.au, 19-Oct-00.
 */

/*
 * Minimal serial functions needed to use one of the SCC ports
 * as serial console interface.
 */

#include <common.h>
#include <asm/cpm_85xx.h>
#include <serial.h>
#include <linux/compiler.h>

DECLARE_GLOBAL_DATA_PTR;

#if defined(CONFIG_CONS_ON_SCC)

#if CONFIG_CONS_INDEX == 1      /* Console on SCC1 */

#define SCC_INDEX               0
#define PROFF_SCC               PROFF_SCC1
#define CMXSCR_MASK             (CMXSCR_GR1|CMXSCR_SC1|\
                                        CMXSCR_RS1CS_MSK|CMXSCR_TS1CS_MSK)
#define CMXSCR_VALUE            (CMXSCR_RS1CS_BRG1|CMXSCR_TS1CS_BRG1)
#define CPM_CR_SCC_PAGE         CPM_CR_SCC1_PAGE
#define CPM_CR_SCC_SBLOCK       CPM_CR_SCC1_SBLOCK

#elif CONFIG_CONS_INDEX == 2    /* Console on SCC2 */

#define SCC_INDEX               1
#define PROFF_SCC               PROFF_SCC2
#define CMXSCR_MASK             (CMXSCR_GR2|CMXSCR_SC2|\
                                        CMXSCR_RS2CS_MSK|CMXSCR_TS2CS_MSK)
#define CMXSCR_VALUE            (CMXSCR_RS2CS_BRG2|CMXSCR_TS2CS_BRG2)
#define CPM_CR_SCC_PAGE         CPM_CR_SCC2_PAGE
#define CPM_CR_SCC_SBLOCK       CPM_CR_SCC2_SBLOCK

#elif CONFIG_CONS_INDEX == 3    /* Console on SCC3 */

#define SCC_INDEX               2
#define PROFF_SCC               PROFF_SCC3
#define CMXSCR_MASK             (CMXSCR_GR3|CMXSCR_SC3|\
                                        CMXSCR_RS3CS_MSK|CMXSCR_TS3CS_MSK)
#define CMXSCR_VALUE            (CMXSCR_RS3CS_BRG3|CMXSCR_TS3CS_BRG3)
#define CPM_CR_SCC_PAGE         CPM_CR_SCC3_PAGE
#define CPM_CR_SCC_SBLOCK       CPM_CR_SCC3_SBLOCK

#elif CONFIG_CONS_INDEX == 4    /* Console on SCC4 */

#define SCC_INDEX               3
#define PROFF_SCC               PROFF_SCC4
#define CMXSCR_MASK             (CMXSCR_GR4|CMXSCR_SC4|\
                                        CMXSCR_RS4CS_MSK|CMXSCR_TS4CS_MSK)
#define CMXSCR_VALUE            (CMXSCR_RS4CS_BRG4|CMXSCR_TS4CS_BRG4)
#define CPM_CR_SCC_PAGE         CPM_CR_SCC4_PAGE
#define CPM_CR_SCC_SBLOCK       CPM_CR_SCC4_SBLOCK

#else

#error "console not correctly defined"

#endif

static int mpc85xx_serial_init(void)
{
        volatile ccsr_cpm_t *cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;
        volatile ccsr_cpm_scc_t *sp;
        volatile scc_uart_t *up;
        volatile cbd_t *tbdf, *rbdf;
        volatile ccsr_cpm_cp_t *cp = &(cpm->im_cpm_cp);
        uint    dpaddr;

        /* initialize pointers to SCC */

        sp = (ccsr_cpm_scc_t *) &(cpm->im_cpm_scc[SCC_INDEX]);
        up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);

        /* Disable transmitter/receiver.
        */
        sp->gsmrl &= ~(SCC_GSMRL_ENR | SCC_GSMRL_ENT);

        /* put the SCC channel into NMSI (non multiplexd serial interface)
         * mode and wire the selected SCC Tx and Rx clocks to BRGx (15-15).
         */
        cpm->im_cpm_mux.cmxscr = \
                (cpm->im_cpm_mux.cmxscr&~CMXSCR_MASK)|CMXSCR_VALUE;

        /* Set up the baud rate generator.
        */
        serial_setbrg ();

        /* Allocate space for two buffer descriptors in the DP ram.
         * damm: allocating space after the two buffers for rx/tx data
         */

        dpaddr = m8560_cpm_dpalloc((2 * sizeof (cbd_t)) + 2, 16);

        /* Set the physical address of the host memory buffers in
         * the buffer descriptors.
         */
        rbdf = (cbd_t *)&(cpm->im_dprambase[dpaddr]);
        rbdf->cbd_bufaddr = (uint) (rbdf+2);
        rbdf->cbd_sc = BD_SC_EMPTY | BD_SC_WRAP;
        tbdf = rbdf + 1;
        tbdf->cbd_bufaddr = ((uint) (rbdf+2)) + 1;
        tbdf->cbd_sc = BD_SC_WRAP;

        /* Set up the uart parameters in the parameter ram.
        */
        up->scc_genscc.scc_rbase = dpaddr;
        up->scc_genscc.scc_tbase = dpaddr+sizeof(cbd_t);
        up->scc_genscc.scc_rfcr = CPMFCR_EB;
        up->scc_genscc.scc_tfcr = CPMFCR_EB;
        up->scc_genscc.scc_mrblr = 1;
        up->scc_maxidl = 0;
        up->scc_brkcr = 1;
        up->scc_parec = 0;
        up->scc_frmec = 0;
        up->scc_nosec = 0;
        up->scc_brkec = 0;
        up->scc_uaddr1 = 0;
        up->scc_uaddr2 = 0;
        up->scc_toseq = 0;
        up->scc_char1 = up->scc_char2 = up->scc_char3 = up->scc_char4 = 0x8000;
        up->scc_char5 = up->scc_char6 = up->scc_char7 = up->scc_char8 = 0x8000;
        up->scc_rccm = 0xc0ff;

        /* Mask all interrupts and remove anything pending.
        */
        sp->sccm = 0;
        sp->scce = 0xffff;

        /* Set 8 bit FIFO, 16 bit oversampling and UART mode.
        */
        sp->gsmrh = SCC_GSMRH_RFW;      /* 8 bit FIFO */
        sp->gsmrl = \
                SCC_GSMRL_TDCR_16 | SCC_GSMRL_RDCR_16 | SCC_GSMRL_MODE_UART;

        /* Set CTS no flow control, 1 stop bit, 8 bit character length,
         * normal async UART mode, no parity
         */
        sp->psmr = SCU_PSMR_CL;

        /* execute the "Init Rx and Tx params" CP command.
        */

        while (cp->cpcr & CPM_CR_FLG)  /* wait if cp is busy */
          ;

        cp->cpcr = mk_cr_cmd(CPM_CR_SCC_PAGE, CPM_CR_SCC_SBLOCK,
                                        0, CPM_CR_INIT_TRX) | CPM_CR_FLG;

        while (cp->cpcr & CPM_CR_FLG)  /* wait if cp is busy */
          ;

        /* Enable transmitter/receiver.
        */
        sp->gsmrl |= SCC_GSMRL_ENR | SCC_GSMRL_ENT;

        return (0);
}

static void mpc85xx_serial_setbrg(void)
{
#if defined(CONFIG_CONS_USE_EXTC)
        m8560_cpm_extcbrg(SCC_INDEX, gd->baudrate,
                CONFIG_CONS_EXTC_RATE, CONFIG_CONS_EXTC_PINSEL);
#else
        m8560_cpm_setbrg(SCC_INDEX, gd->baudrate);
#endif
}

static void mpc85xx_serial_putc(const char c)
{
        volatile scc_uart_t     *up;
        volatile cbd_t          *tbdf;
        volatile ccsr_cpm_t     *cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;

        if (c == '\n')
                serial_putc ('\r');

        up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
        tbdf = (cbd_t *)&(cpm->im_dprambase[up->scc_genscc.scc_tbase]);

        /* Wait for last character to go.
         */
        while (tbdf->cbd_sc & BD_SC_READY)
                ;

        /* Load the character into the transmit buffer.
         */
        *(volatile char *)tbdf->cbd_bufaddr = c;
        tbdf->cbd_datlen = 1;
        tbdf->cbd_sc |= BD_SC_READY;
}

static int mpc85xx_serial_getc(void)
{
        volatile cbd_t          *rbdf;
        volatile scc_uart_t     *up;
        volatile ccsr_cpm_t     *cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;
        unsigned char           c;

        up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
        rbdf = (cbd_t *)&(cpm->im_dprambase[up->scc_genscc.scc_rbase]);

        /* Wait for character to show up.
         */
        while (rbdf->cbd_sc & BD_SC_EMPTY)
                ;

        /* Grab the char and clear the buffer again.
         */
        c = *(volatile unsigned char *)rbdf->cbd_bufaddr;
        rbdf->cbd_sc |= BD_SC_EMPTY;

        return (c);
}

static int mpc85xx_serial_tstc(void)
{
        volatile cbd_t          *rbdf;
        volatile scc_uart_t     *up;
        volatile ccsr_cpm_t     *cpm = (ccsr_cpm_t *)CONFIG_SYS_MPC85xx_CPM_ADDR;

        up = (scc_uart_t *)&(cpm->im_dprambase[PROFF_SCC]);
        rbdf = (cbd_t *)&(cpm->im_dprambase[up->scc_genscc.scc_rbase]);

        return ((rbdf->cbd_sc & BD_SC_EMPTY) == 0);
}

static struct serial_device mpc85xx_serial_drv = {
        .name   = "mpc85xx_serial",
        .start  = mpc85xx_serial_init,
        .stop   = NULL,
        .setbrg = mpc85xx_serial_setbrg,
        .putc   = mpc85xx_serial_putc,
        .puts   = default_serial_puts,
        .getc   = mpc85xx_serial_getc,
        .tstc   = mpc85xx_serial_tstc,
};

void mpc85xx_serial_initialize(void)
{
        serial_register(&mpc85xx_serial_drv);
}

__weak struct serial_device *default_serial_console(void)
{
        return &mpc85xx_serial_drv;
}
#endif  /* CONFIG_CONS_ON_SCC */