diff options
Diffstat (limited to 'cpu/mips/serial.c')
| -rw-r--r-- | cpu/mips/serial.c | 282 |
1 files changed, 282 insertions, 0 deletions
diff --git a/cpu/mips/serial.c b/cpu/mips/serial.c new file mode 100644 index 0000000..ebda509 --- /dev/null +++ b/cpu/mips/serial.c @@ -0,0 +1,282 @@ +/* + * (INCA) ASC UART support + */ + +#include <common.h> +#include <asm/inca-ip.h> +#include "serial.h" + +#define SET_BIT(reg, mask) reg |= (mask) +#define CLEAR_BIT(reg, mask) reg &= (~mask) +#define CLEAR_BITS(reg, mask) CLEAR_BIT(reg, mask) +#define SET_BITS(reg, mask) SET_BIT(reg, mask) +#define SET_BITFIELD(reg, mask, off, val) {reg &= (~mask); reg |= (val << off);} + +extern uint incaip_get_fpiclk(void); + +static int serial_setopt (void); + +/* pointer to ASC register base address */ +static volatile incaAsc_t *pAsc = (incaAsc_t *)INCA_IP_ASC; + +/****************************************************************************** +* +* serial_init - initialize a INCAASC channel +* +* This routine initializes the number of data bits, parity +* and set the selected baud rate. Interrupts are disabled. +* Set the modem control signals if the option is selected. +* +* RETURNS: N/A +*/ + +int serial_init (void) +{ + /* we have to set PMU.EN13 bit to enable an ASC device*/ + INCAASC_PMU_ENABLE(13); + + /* and we have to set CLC register*/ + CLEAR_BIT(pAsc->asc_clc, ASCCLC_DISS); + SET_BITFIELD(pAsc->asc_clc, ASCCLC_RMCMASK, ASCCLC_RMCOFFSET, 0x0001); + + /* initialy we are in async mode */ + pAsc->asc_con = ASCCON_M_8ASYNC; + + /* select input port */ + pAsc->asc_pisel = (CONSOLE_TTY & 0x1); + + /* TXFIFO's filling level */ + SET_BITFIELD(pAsc->asc_txfcon, ASCTXFCON_TXFITLMASK, + ASCTXFCON_TXFITLOFF, INCAASC_TXFIFO_FL); + /* enable TXFIFO */ + SET_BIT(pAsc->asc_txfcon, ASCTXFCON_TXFEN); + + /* RXFIFO's filling level */ + SET_BITFIELD(pAsc->asc_txfcon, ASCRXFCON_RXFITLMASK, + ASCRXFCON_RXFITLOFF, INCAASC_RXFIFO_FL); + /* enable RXFIFO */ + SET_BIT(pAsc->asc_rxfcon, ASCRXFCON_RXFEN); + + /* enable error signals */ + SET_BIT(pAsc->asc_con, ASCCON_FEN); + SET_BIT(pAsc->asc_con, ASCCON_OEN); + + /* acknowledge ASC interrupts */ + ASC_INTERRUPTS_CLEAR(INCAASC_IRQ_LINE_ALL); + + /* disable ASC interrupts */ + ASC_INTERRUPTS_DISABLE(INCAASC_IRQ_LINE_ALL); + + /* set FIFOs into the transparent mode */ + SET_BIT(pAsc->asc_txfcon, ASCTXFCON_TXTMEN); + SET_BIT(pAsc->asc_rxfcon, ASCRXFCON_RXTMEN); + + /* set baud rate */ + serial_setbrg(); + + /* set the options */ + serial_setopt(); + + return 0; +} + +void serial_setbrg (void) +{ + ulong uiReloadValue, fdv; + ulong f_ASC; + + f_ASC = incaip_get_fpiclk(); + +#ifndef INCAASC_USE_FDV + fdv = 2; + uiReloadValue = (f_ASC / (fdv * 16 * CONFIG_BAUDRATE)) - 1; +#else + fdv = INCAASC_FDV_HIGH_BAUDRATE; + uiReloadValue = (f_ASC / (8192 * CONFIG_BAUDRATE / fdv)) - 1; +#endif /* INCAASC_USE_FDV */ + + if ( (uiReloadValue < 0) || (uiReloadValue > 8191) ) + { +#ifndef INCAASC_USE_FDV + fdv = 3; + uiReloadValue = (f_ASC / (fdv * 16 * CONFIG_BAUDRATE)) - 1; +#else + fdv = INCAASC_FDV_LOW_BAUDRATE; + uiReloadValue = (f_ASC / (8192 * CONFIG_BAUDRATE / fdv)) - 1; +#endif /* INCAASC_USE_FDV */ + + if ( (uiReloadValue < 0) || (uiReloadValue > 8191) ) + { + return; /* can't impossibly generate that baud rate */ + } + } + + /* Disable Baud Rate Generator; BG should only be written when R=0 */ + CLEAR_BIT(pAsc->asc_con, ASCCON_R); + +#ifndef INCAASC_USE_FDV + /* + * Disable Fractional Divider (FDE) + * Divide clock by reload-value + constant (BRS) + */ + /* FDE = 0 */ + CLEAR_BIT(pAsc->asc_con, ASCCON_FDE); + + if ( fdv == 2 ) + CLEAR_BIT(pAsc->asc_con, ASCCON_BRS); /* BRS = 0 */ + else + SET_BIT(pAsc->asc_con, ASCCON_BRS); /* BRS = 1 */ + +#else /* INCAASC_USE_FDV */ + + /* Enable Fractional Divider */ + SET_BIT(pAsc->asc_con, ASCCON_FDE); /* FDE = 1 */ + + /* Set fractional divider value */ + pAsc->asc_fdv = fdv & ASCFDV_VALUE_MASK; + +#endif /* INCAASC_USE_FDV */ + + /* Set reload value in BG */ + pAsc->asc_bg = uiReloadValue; + + /* Enable Baud Rate Generator */ + SET_BIT(pAsc->asc_con, ASCCON_R); /* R = 1 */ +} + +/******************************************************************************* +* +* serial_setopt - set the serial options +* +* Set the channel operating mode to that specified. Following options +* are supported: CREAD, CSIZE, PARENB, and PARODD. +* +* Note, this routine disables the transmitter. The calling routine +* may have to re-enable it. +* +* RETURNS: +* Returns 0 to indicate success, otherwise -1 is returned +*/ + +static int serial_setopt (void) +{ + ulong con; + + switch ( ASC_OPTIONS & ASCOPT_CSIZE ) + { + /* 7-bit-data */ + case ASCOPT_CS7: + con = ASCCON_M_7ASYNCPAR; /* 7-bit-data and parity bit */ + break; + + /* 8-bit-data */ + case ASCOPT_CS8: + if ( ASC_OPTIONS & ASCOPT_PARENB ) + con = ASCCON_M_8ASYNCPAR; /* 8-bit-data and parity bit */ + else + con = ASCCON_M_8ASYNC; /* 8-bit-data no parity */ + break; + + /* + * only 7 and 8-bit frames are supported + * if we don't use IOCTL extensions + */ + default: + return -1; + } + + if ( ASC_OPTIONS & ASCOPT_STOPB ) + SET_BIT(con, ASCCON_STP); /* 2 stop bits */ + else + CLEAR_BIT(con, ASCCON_STP); /* 1 stop bit */ + + if ( ASC_OPTIONS & ASCOPT_PARENB ) + SET_BIT(con, ASCCON_PEN); /* enable parity checking */ + else + CLEAR_BIT(con, ASCCON_PEN); /* disable parity checking */ + + if ( ASC_OPTIONS & ASCOPT_PARODD ) + SET_BIT(con, ASCCON_ODD); /* odd parity */ + else + CLEAR_BIT(con, ASCCON_ODD); /* even parity */ + + if ( ASC_OPTIONS & ASCOPT_CREAD ) + SET_BIT(pAsc->asc_whbcon, ASCWHBCON_SETREN); /* Receiver enable */ + + pAsc->asc_con |= con; + + return 0; +} + +void serial_putc (const char c) +{ + uint txFl = 0; + + if (c == '\n') serial_putc ('\r'); + + /* check do we have a free space in the TX FIFO */ + /* get current filling level */ + do + { + txFl = ( pAsc->asc_fstat & ASCFSTAT_TXFFLMASK ) >> ASCFSTAT_TXFFLOFF; + } + while ( txFl == INCAASC_TXFIFO_FULL ); + + pAsc->asc_tbuf = c; /* write char to Transmit Buffer Register */ + /* check for errors */ + if ( pAsc->asc_con & ASCCON_OE ) + { + SET_BIT(pAsc->asc_whbcon, ASCWHBCON_CLROE); + return; + } +} + +void serial_puts (const char *s) +{ + while (*s) + { + serial_putc (*s++); + } +} + +int serial_getc (void) +{ + ulong symbol_mask; + char c; + + while (!serial_tstc()); + + symbol_mask = + ((ASC_OPTIONS & ASCOPT_CSIZE) == ASCOPT_CS7) ? (0x7f) : (0xff); + + c = (char)(pAsc->asc_rbuf & symbol_mask); + + return c; +} + +int serial_tstc (void) +{ + int res = 1; + + if ( (pAsc->asc_fstat & ASCFSTAT_RXFFLMASK) == 0 ) + { + res = 0; + } + else if ( pAsc->asc_con & ASCCON_FE ) + { + SET_BIT(pAsc->asc_whbcon, ASCWHBCON_CLRFE); + res = 0; + } + else if ( pAsc->asc_con & ASCCON_PE ) + { + SET_BIT(pAsc->asc_whbcon, ASCWHBCON_CLRPE); + res = 0; + } + else if ( pAsc->asc_con & ASCCON_OE ) + { + SET_BIT(pAsc->asc_whbcon, ASCWHBCON_CLROE); + res = 0; + } + + return res; +} |