freebsd-dev/sys/dev/uart/uart_dev_mvebu.c
Andrew Turner c81131d9ec Disable EARLY_PRINTF from the Armada 3700 uart, it breaks when we want
to use EARLY_PRINTF on other SoCs.

Sponsored by:	DARPA, AFRL
2018-02-01 15:05:17 +00:00

618 lines
15 KiB
C

/*-
* Copyright (c) 2017 Semihalf.
* 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 AUTHOR 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 AUTHOR 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>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <machine/bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <dev/uart/uart.h>
#include <dev/uart/uart_bus.h>
#include <dev/uart/uart_cpu.h>
#include <dev/uart/uart_cpu_fdt.h>
#include "uart_if.h"
#define UART_RBR 0x00 /* Receiver Buffer */
#define RBR_BRK_DET (1 << 15) /* Break Detect */
#define RBR_FRM_ERR_DET (1 << 14) /* Frame Error Detect */
#define RBR_PAR_ERR_DET (1 << 13) /* Parity Error Detect */
#define RBR_OVR_ERR_DET (1 << 12) /* Overrun Error */
#define UART_TSH 0x04 /* Transmitter Holding Register */
#define UART_CTRL 0x08 /* Control Register */
#define CTRL_SOFT_RST (1 << 31) /* Soft Reset */
#define CTRL_TX_FIFO_RST (1 << 15) /* TX FIFO Reset */
#define CTRL_RX_FIFO_RST (1 << 14) /* RX FIFO Reset */
#define CTRL_ST_MIRR_EN (1 << 13) /* Status Mirror Enable */
#define CTRL_LPBK_EN (1 << 12) /* Loopback Mode Enable */
#define CTRL_SND_BRK_SEQ (1 << 11) /* Send Break Sequence */
#define CTRL_PAR_EN (1 << 10) /* Parity Enable */
#define CTRL_TWO_STOP (1 << 9) /* Two Stop Bits */
#define CTRL_TX_HALF_INT (1 << 8) /* TX Half-Full Interrupt Enable */
#define CTRL_RX_HALF_INT (1 << 7) /* RX Half-Full Interrupt Enable */
#define CTRL_TX_EMPT_INT (1 << 6) /* TX Empty Interrupt Enable */
#define CTRL_TX_RDY_INT (1 << 5) /* TX Ready Interrupt Enable */
#define CTRL_RX_RDY_INT (1 << 4) /* RX Ready Interrupt Enable */
#define CTRL_BRK_DET_INT (1 << 3) /* Break Detect Interrupt Enable */
#define CTRL_FRM_ERR_INT (1 << 2) /* Frame Error Interrupt Enable */
#define CTRL_PAR_ERR_INT (1 << 1) /* Parity Error Interrupt Enable */
#define CTRL_OVR_ERR_INT (1 << 0) /* Overrun Error Interrupt Enable */
#define CTRL_INTR_MASK 0x1ff
#define CTRL_TX_IDLE_INT CTRL_TX_RDY_INT
#define CTRL_IPEND_MASK (CTRL_OVR_ERR_INT | CTRL_BRK_DET_INT | \
CTRL_RX_RDY_INT)
#define UART_STAT 0x0c /* Status Register */
#define STAT_TX_FIFO_EMPT (1 << 13) /* TX FIFO Empty */
#define STAT_RX_FIFO_EMPT (1 << 12) /* RX FIFO Empty */
#define STAT_TX_FIFO_FULL (1 << 11) /* TX FIFO Full */
#define STAT_TX_FIFO_HALF (1 << 10) /* TX FIFO Half Full */
#define STAT_RX_TOGL (1 << 9) /* RX Toogled */
#define STAT_RX_FIFO_FULL (1 << 8) /* RX FIFO Full */
#define STAT_RX_FIFO_HALF (1 << 7) /* RX FIFO Half Full */
#define STAT_TX_EMPT (1 << 6) /* TX Empty */
#define STAT_TX_RDY (1 << 5) /* TX Ready */
#define STAT_RX_RDY (1 << 4) /* RX Ready */
#define STAT_BRK_DET (1 << 3) /* Break Detect */
#define STAT_FRM_ERR (1 << 2) /* Frame Error */
#define STAT_PAR_ERR (1 << 1) /* Parity Error */
#define STAT_OVR_ERR (1 << 0) /* Overrun Error */
#define STAT_TX_IDLE STAT_TX_RDY
#define STAT_TRANS_MASK (STAT_OVR_ERR | STAT_BRK_DET | STAT_RX_RDY)
#define UART_CCR 0x10 /* Clock Control Register */
#define CCR_BAUDRATE_DIV 0x3ff /* Baud Rate Divisor */
#define DEFAULT_RCLK 25804800
#define ONE_FRAME_TIME 87
#define stat_ipend_trans(i) ( \
(i & STAT_OVR_ERR) << 16 | \
(i & STAT_BRK_DET) << 14 | \
(i & STAT_RX_RDY) << 14)
/*
* For debugging purposes
*/
#if 0
#ifdef EARLY_PRINTF
#if defined(SOCDEV_PA) && defined(SOCDEV_VA)
#define UART_REG_OFFSET 0x12000
static void
uart_mvebu_early_putc(int c)
{
volatile uint32_t *tsh;
volatile uint32_t *stat;
tsh = (uint32_t *)(SOCDEV_VA + UART_REG_OFFSET + UART_TSH);
stat = (uint32_t *)(SOCDEV_VA + UART_REG_OFFSET + UART_STAT);
while(!(*stat & STAT_TX_RDY))
;
*tsh = c & 0xff;
}
early_putc_t *early_putc = uart_mvebu_early_putc;
#endif
#endif
#endif
/*
* Low-level UART interface.
*/
static int uart_mvebu_probe(struct uart_bas *);
static void uart_mvebu_init(struct uart_bas *, int, int, int, int);
static void uart_mvebu_putc(struct uart_bas *, int);
static int uart_mvebu_rxready(struct uart_bas *);
static int uart_mvebu_getc(struct uart_bas *, struct mtx *);
static struct uart_ops uart_mvebu_ops = {
.probe = uart_mvebu_probe,
.init = uart_mvebu_init,
.term = NULL,
.putc = uart_mvebu_putc,
.rxready = uart_mvebu_rxready,
.getc = uart_mvebu_getc,
};
static int
uart_mvebu_probe(struct uart_bas *bas)
{
return (0);
}
static int
uart_mvebu_divisor(int rclk, int baudrate)
{
int divisor;
if (baudrate == 0)
return (0);
divisor = (rclk >> 4) / baudrate;
if (divisor <= 1 || divisor >= 1024)
return (0);
return (divisor);
}
static int
uart_mvebu_param(struct uart_bas *bas, int baudrate, int databits, int stopbits,
int parity)
{
uint32_t ctrl = 0;
uint32_t ccr;
int divisor, ret = 0;
/* Reset UART */
ctrl = uart_getreg(bas, UART_CTRL);
uart_setreg(bas, UART_CTRL, ctrl | CTRL_TX_FIFO_RST | CTRL_RX_FIFO_RST |
CTRL_LPBK_EN);
uart_barrier(bas);
switch (stopbits) {
case 2:
ctrl |= CTRL_TWO_STOP;
break;
case 1:
default:
ctrl &=~ CTRL_TWO_STOP;
}
switch (parity) {
case 3: /* Even parity bit */
ctrl |= CTRL_PAR_EN;
break;
default:
ctrl &=~ CTRL_PAR_EN;
}
/* Set baudrate. */
if (baudrate > 0) {
divisor = uart_mvebu_divisor(bas->rclk, baudrate);
if (divisor == 0) {
ret = EINVAL;
} else {
ccr = uart_getreg(bas, UART_CCR);
ccr &=~CCR_BAUDRATE_DIV;
uart_setreg(bas, UART_CCR, ccr | divisor);
uart_barrier(bas);
}
}
/* Set mirroring of status bits */
ctrl |= CTRL_ST_MIRR_EN;
uart_setreg(bas, UART_CTRL, ctrl);
uart_barrier(bas);
return (ret);
}
static void
uart_mvebu_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
int parity)
{
/* Set default frequency */
bas->rclk = DEFAULT_RCLK;
/* Mask interrupts */
uart_setreg(bas, UART_CTRL, uart_getreg(bas, UART_CTRL) &
~CTRL_INTR_MASK);
uart_barrier(bas);
uart_mvebu_param(bas, baudrate, databits, stopbits, parity);
}
static void
uart_mvebu_putc(struct uart_bas *bas, int c)
{
while (uart_getreg(bas, UART_STAT) & STAT_TX_FIFO_FULL)
;
uart_setreg(bas, UART_TSH, c & 0xff);
}
static int
uart_mvebu_rxready(struct uart_bas *bas)
{
if (uart_getreg(bas, UART_STAT) & STAT_RX_RDY)
return 1;
return 0;
}
static int
uart_mvebu_getc(struct uart_bas *bas, struct mtx *hwmtx)
{
int c;
uart_lock(hwmtx);
while (!(uart_getreg(bas, UART_STAT) & STAT_RX_RDY))
;
c = uart_getreg(bas, UART_RBR) & 0xff;
uart_unlock(hwmtx);
return c;
}
/*
* UART driver methods implementation.
*/
struct uart_mvebu_softc {
struct uart_softc base;
uint16_t intrm;
};
static int uart_mvebu_bus_attach(struct uart_softc *);
static int uart_mvebu_bus_detach(struct uart_softc *);
static int uart_mvebu_bus_flush(struct uart_softc *, int);
static int uart_mvebu_bus_getsig(struct uart_softc *);
static int uart_mvebu_bus_ioctl(struct uart_softc *, int, intptr_t);
static int uart_mvebu_bus_ipend(struct uart_softc *);
static int uart_mvebu_bus_param(struct uart_softc *, int, int, int, int);
static int uart_mvebu_bus_probe(struct uart_softc *);
static int uart_mvebu_bus_receive(struct uart_softc *);
static int uart_mvebu_bus_setsig(struct uart_softc *, int);
static int uart_mvebu_bus_transmit(struct uart_softc *);
static void uart_mvebu_bus_grab(struct uart_softc *);
static void uart_mvebu_bus_ungrab(struct uart_softc *);
static kobj_method_t uart_mvebu_methods[] = {
KOBJMETHOD(uart_attach, uart_mvebu_bus_attach),
KOBJMETHOD(uart_detach, uart_mvebu_bus_detach),
KOBJMETHOD(uart_flush, uart_mvebu_bus_flush),
KOBJMETHOD(uart_getsig, uart_mvebu_bus_getsig),
KOBJMETHOD(uart_ioctl, uart_mvebu_bus_ioctl),
KOBJMETHOD(uart_ipend, uart_mvebu_bus_ipend),
KOBJMETHOD(uart_param, uart_mvebu_bus_param),
KOBJMETHOD(uart_probe, uart_mvebu_bus_probe),
KOBJMETHOD(uart_receive, uart_mvebu_bus_receive),
KOBJMETHOD(uart_setsig, uart_mvebu_bus_setsig),
KOBJMETHOD(uart_transmit, uart_mvebu_bus_transmit),
KOBJMETHOD(uart_grab, uart_mvebu_bus_grab),
KOBJMETHOD(uart_ungrab, uart_mvebu_bus_ungrab),
{ 0, 0 }
};
struct uart_class uart_mvebu_class = {
"mvebu-uart",
uart_mvebu_methods,
sizeof(struct uart_mvebu_softc),
.uc_ops = &uart_mvebu_ops,
.uc_range = 0x14,
.uc_rclk = DEFAULT_RCLK,
.uc_rshift = 0,
.uc_riowidth = 4
};
static struct ofw_compat_data compat_data[] = {
{"marvell,armada-3700-uart", (uintptr_t)&uart_mvebu_class},
{NULL, (uintptr_t)NULL},
};
UART_FDT_CLASS_AND_DEVICE(compat_data);
static int
uart_mvebu_bus_attach(struct uart_softc *sc)
{
struct uart_bas *bas;
int ctrl;
bas = &sc->sc_bas;
uart_lock(sc->sc_hwmtx);
ctrl = uart_getreg(bas, UART_CTRL);
/* Enable interrupts */
ctrl &=~ CTRL_INTR_MASK;
ctrl |= CTRL_IPEND_MASK;
/* Set interrupts */
uart_setreg(bas, UART_CTRL, ctrl);
uart_barrier(bas);
uart_unlock(sc->sc_hwmtx);
return (0);
}
static int
uart_mvebu_bus_detach(struct uart_softc *sc)
{
return (0);
}
static int
uart_mvebu_bus_flush(struct uart_softc *sc, int what)
{
struct uart_bas *bas;
int ctrl, ret = 0;
bas = &sc->sc_bas;
uart_lock(sc->sc_hwmtx);
ctrl = uart_getreg(bas, UART_CTRL);
switch (what) {
case UART_FLUSH_RECEIVER:
uart_setreg(bas, UART_CTRL, ctrl | CTRL_RX_FIFO_RST);
uart_barrier(bas);
break;
case UART_FLUSH_TRANSMITTER:
uart_setreg(bas, UART_CTRL, ctrl | CTRL_TX_FIFO_RST);
uart_barrier(bas);
break;
default:
ret = EINVAL;
break;
}
/* Back to normal operation */
if (!ret) {
uart_setreg(bas, UART_CTRL, ctrl);
uart_barrier(bas);
}
uart_unlock(sc->sc_hwmtx);
return (ret);
}
static int
uart_mvebu_bus_getsig(struct uart_softc *sc)
{
return (0);
}
static int
uart_mvebu_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
{
struct uart_bas *bas;
int ctrl, ret = 0;
int divisor, baudrate;
bas = &sc->sc_bas;
uart_lock(sc->sc_hwmtx);
switch (request) {
case UART_IOCTL_BREAK:
ctrl = uart_getreg(bas, UART_CTRL);
if (data)
ctrl |= CTRL_SND_BRK_SEQ;
else
ctrl &=~ CTRL_SND_BRK_SEQ;
uart_setreg(bas, UART_CTRL, ctrl);
uart_barrier(bas);
break;
case UART_IOCTL_BAUD:
divisor = uart_getreg(bas, UART_CCR) & CCR_BAUDRATE_DIV;
baudrate = bas->rclk/(divisor * 16);
*(int *)data = baudrate;
break;
default:
ret = ENOTTY;
break;
}
uart_unlock(sc->sc_hwmtx);
return (ret);
}
static int
uart_mvebu_bus_ipend(struct uart_softc *sc)
{
struct uart_bas *bas;
int ipend, ctrl, ret = 0;
bas = &sc->sc_bas;
uart_lock(sc->sc_hwmtx);
ipend = uart_getreg(bas, UART_STAT);
ctrl = uart_getreg(bas, UART_CTRL);
if (((ipend & STAT_TX_IDLE) == STAT_TX_IDLE) &&
(ctrl & CTRL_TX_IDLE_INT) == CTRL_TX_IDLE_INT) {
/* Disable TX IDLE Interrupt generation */
uart_setreg(bas, UART_CTRL, ctrl & ~CTRL_TX_IDLE_INT);
uart_barrier(bas);
/* SER_INT_TXIDLE means empty TX FIFO. Wait until it cleans */
while(!(uart_getreg(bas, UART_STAT) & STAT_TX_FIFO_EMPT))
DELAY(ONE_FRAME_TIME/2);
ret |= SER_INT_TXIDLE;
}
ret |= stat_ipend_trans(ipend & STAT_TRANS_MASK);
uart_unlock(sc->sc_hwmtx);
return (ret);
}
static int
uart_mvebu_bus_param(struct uart_softc *sc, int baudrate, int databits,
int stopbits, int parity)
{
int ret;
uart_lock(sc->sc_hwmtx);
ret = uart_mvebu_param(&sc->sc_bas, baudrate, databits, stopbits, parity);
uart_unlock(sc->sc_hwmtx);
return (ret);
}
static int
uart_mvebu_bus_probe(struct uart_softc *sc)
{
if (!ofw_bus_status_okay(sc->sc_dev))
return (ENXIO);
if (!ofw_bus_search_compatible(sc->sc_dev, compat_data)->ocd_data)
return (ENXIO);
device_set_desc(sc->sc_dev, "Marvell Armada 3700 UART");
sc->sc_txfifosz = 32;
sc->sc_rxfifosz = 64;
sc->sc_hwiflow = 0;
sc->sc_hwoflow = 0;
return (0);
}
int
uart_mvebu_bus_receive(struct uart_softc *sc)
{
struct uart_bas *bas;
uint32_t xc;
int rx, er;
bas = &sc->sc_bas;
uart_lock(sc->sc_hwmtx);
while (!(uart_getreg(bas, UART_STAT) & STAT_RX_FIFO_EMPT)) {
if (uart_rx_full(sc)) {
sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
break;
}
xc = uart_getreg(bas, UART_RBR);
rx = xc & 0xff;
er = xc & 0xf000;
/*
* Formula which translates marvell error bits
* Only valid when CTRL_ST_MIRR_EN is set
*/
er = (er & RBR_BRK_DET) >> 7 |
(er & RBR_FRM_ERR_DET) >> 5 |
(er & RBR_PAR_ERR_DET) >> 2 |
(er & RBR_OVR_ERR_DET) >> 2;
uart_rx_put(sc, rx | er);
uart_barrier(bas);
}
/*
* uart_if.m says that receive interrupt
* should be cleared, so we need to reset
* RX FIFO
*/
if (!(uart_getreg(bas, UART_STAT) & STAT_RX_FIFO_EMPT)) {
uart_mvebu_bus_flush(sc, UART_FLUSH_RECEIVER);
}
uart_unlock(sc->sc_hwmtx);
return (0);
}
static int
uart_mvebu_bus_setsig(struct uart_softc *sc, int sig)
{
/* Not supported by hardware */
return (0);
}
int
uart_mvebu_bus_transmit(struct uart_softc *sc)
{
struct uart_bas *bas;
int i, ctrl;
bas = &sc->sc_bas;
uart_lock(sc->sc_hwmtx);
/* Turn off all interrupts during send */
ctrl = uart_getreg(bas, UART_CTRL);
uart_setreg(bas, UART_CTRL, ctrl & ~CTRL_INTR_MASK);
uart_barrier(bas);
for (i = 0; i < sc->sc_txdatasz; i++) {
uart_setreg(bas, UART_TSH, sc->sc_txbuf[i] & 0xff);
uart_barrier(bas);
}
/*
* Make sure that interrupt is generated
* when FIFO can get more data.
*/
uart_setreg(bas, UART_CTRL, ctrl | CTRL_TX_IDLE_INT);
uart_barrier(bas);
/* Mark busy */
sc->sc_txbusy = 1;
uart_unlock(sc->sc_hwmtx);
return (0);
}
static void
uart_mvebu_bus_grab(struct uart_softc *sc)
{
struct uart_mvebu_softc *msc = (struct uart_mvebu_softc *)sc;
struct uart_bas *bas = &sc->sc_bas;
uint32_t ctrl;
/* Mask all interrupts */
uart_lock(sc->sc_hwmtx);
ctrl = uart_getreg(bas, UART_CTRL);
msc->intrm = ctrl & CTRL_INTR_MASK;
uart_setreg(bas, UART_CTRL, ctrl & ~CTRL_INTR_MASK);
uart_barrier(bas);
uart_unlock(sc->sc_hwmtx);
}
static void
uart_mvebu_bus_ungrab(struct uart_softc *sc)
{
struct uart_mvebu_softc *msc = (struct uart_mvebu_softc *)sc;
struct uart_bas *bas = &sc->sc_bas;
uint32_t ctrl;
/* Restore interrupts */
uart_lock(sc->sc_hwmtx);
ctrl = uart_getreg(bas, UART_CTRL) & ~CTRL_INTR_MASK;
uart_setreg(bas, UART_CTRL, ctrl | msc->intrm);
uart_barrier(bas);
uart_unlock(sc->sc_hwmtx);
}