d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Enable pl011 UART FIFOs

Browse Source 
The pl011 UART has a 16 entry Tx FIFO and a 16 entry Rx FIFO that
have not been used so far. Update the driver to enable the FIFOs
and use them in transmit and receive.

Reviewed by:	andrew
Differential Revision:	https://reviews.freebsd.org/D8819
This commit is contained in:
Jayachandran C. 2017-02-26 22:05:22 +00:00
parent 55157631f1
commit 43ad57d358
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=314318
1 changed files with 8 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
sys/dev/uart/uart_dev_pl011.c
View File

@ -61,6 +61,7 @@ __FBSDID("$FreeBSD$");
#define DR_OE (1 << 11) /* Overrun error */
#define UART_FR 0x06 /* Flag register */
#define FR_RXFE (1 << 4) /* Receive FIFO/reg empty */
#define FR_TXFF (1 << 5) /* Transmit FIFO/reg full */
#define FR_RXFF (1 << 6) /* Receive FIFO/reg full */
#define FR_TXFE (1 << 7) /* Transmit FIFO/reg empty */
@ -171,9 +172,9 @@ uart_pl011_param(struct uart_bas *bas, int baudrate, int databits, int stopbits,
line |= LCR_H_PEN;
else
line &= ~LCR_H_PEN;
line |= LCR_H_FEN;
/* Configure the rest */
line &= ~LCR_H_FEN;
ctrl |= (CR_RXE | CR_TXE | CR_UARTEN);
if (bas->rclk != 0 && baudrate != 0) {
@ -219,7 +220,7 @@ static int
uart_pl011_rxready(struct uart_bas *bas)
{
return (__uart_getreg(bas, UART_FR) & FR_RXFF);
return !(__uart_getreg(bas, UART_FR) & FR_RXFE);
}
static int
@ -417,8 +418,8 @@ uart_pl011_bus_probe(struct uart_softc *sc)
device_set_desc(sc->sc_dev, "PrimeCell UART (PL011)");
sc->sc_rxfifosz = 1;
sc->sc_txfifosz = 1;
sc->sc_rxfifosz = 16;
sc->sc_txfifosz = 16;
return (0);
}
@ -440,7 +441,6 @@ uart_pl011_bus_receive(struct uart_softc *sc)
break;
}
__uart_setreg(bas, UART_ICR, (UART_RXREADY | RIS_RTIM));
xc = __uart_getreg(bas, UART_DR);
rx = xc & 0xff;
@ -481,20 +481,12 @@ uart_pl011_bus_transmit(struct uart_softc *sc)
uart_barrier(bas);
}
/* If not empty wait until it is */
if ((__uart_getreg(bas, UART_FR) & FR_TXFE) != FR_TXFE) {
sc->sc_txbusy = 1;
/* Enable TX interrupt */
__uart_setreg(bas, UART_IMSC, psc->imsc);
}
/* Mark busy and enable TX interrupt */
sc->sc_txbusy = 1;
__uart_setreg(bas, UART_IMSC, psc->imsc);
uart_unlock(sc->sc_hwmtx);
/* No interrupt expected, schedule the next fifo write */
if (!sc->sc_txbusy)
uart_sched_softih(sc, SER_INT_TXIDLE);
return (0);
}