freebsd-dev/sys/dev/uart/uart_dev_pl011.c
Ed Maste f89f4898a3 Add quirk for ignoring SPCR AccessWidth values on the PL011 UART
The SPCR table on the Lenovo HR330A Ampere eMAG server indicates 8-bit
access, but 32-bit access is required for the PL011 to work.

PL011 on SBSA platforms always supports 32-bit access (and that was
hardcoded here before my EC2 fix), let's use 32-bit access for PL011
and 32BIT interface types.

Tested by emaste on Ampere eMAG and Cavium/Marvell ThunderX2.

Submitted by:	Greg V <greg@unrelenting.technology>
Reviewed by:	andrew, imp (earlier)
Differential Revision:	https://reviews.freebsd.org/D19507
2019-04-15 13:41:53 +00:00

615 lines
16 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2012 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 "opt_acpi.h"
#include "opt_platform.h"
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/bus.h>
#include <machine/bus.h>
#include <machine/machdep.h>
#include <dev/uart/uart.h>
#include <dev/uart/uart_cpu.h>
#ifdef FDT
#include <dev/uart/uart_cpu_fdt.h>
#include <dev/ofw/ofw_bus.h>
#endif
#include <dev/uart/uart_bus.h>
#include "uart_if.h"
#ifdef DEV_ACPI
#include <dev/uart/uart_cpu_acpi.h>
#include <contrib/dev/acpica/include/acpi.h>
#include <contrib/dev/acpica/include/accommon.h>
#include <contrib/dev/acpica/include/actables.h>
#endif
#include <sys/kdb.h>
#ifdef __aarch64__
#define IS_FDT (arm64_bus_method == ARM64_BUS_FDT)
#elif defined(FDT)
#define IS_FDT 1
#else
#error Unsupported configuration
#endif
/* PL011 UART registers and masks*/
#define UART_DR 0x00 /* Data register */
#define DR_FE (1 << 8) /* Framing error */
#define DR_PE (1 << 9) /* Parity error */
#define DR_BE (1 << 10) /* Break error */
#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 */
#define UART_IBRD 0x09 /* Integer baud rate register */
#define IBRD_BDIVINT 0xffff /* Significant part of int. divisor value */
#define UART_FBRD 0x0a /* Fractional baud rate register */
#define FBRD_BDIVFRAC 0x3f /* Significant part of frac. divisor value */
#define UART_LCR_H 0x0b /* Line control register */
#define LCR_H_WLEN8 (0x3 << 5)
#define LCR_H_WLEN7 (0x2 << 5)
#define LCR_H_WLEN6 (0x1 << 5)
#define LCR_H_FEN (1 << 4) /* FIFO mode enable */
#define LCR_H_STP2 (1 << 3) /* 2 stop frames at the end */
#define LCR_H_EPS (1 << 2) /* Even parity select */
#define LCR_H_PEN (1 << 1) /* Parity enable */
#define UART_CR 0x0c /* Control register */
#define CR_RXE (1 << 9) /* Receive enable */
#define CR_TXE (1 << 8) /* Transmit enable */
#define CR_UARTEN (1 << 0) /* UART enable */
#define UART_IFLS 0x0d /* FIFO level select register */
#define IFLS_RX_SHIFT 3 /* RX level in bits [5:3] */
#define IFLS_TX_SHIFT 0 /* TX level in bits [2:0] */
#define IFLS_MASK 0x07 /* RX/TX level is 3 bits */
#define IFLS_LVL_1_8th 0 /* Interrupt at 1/8 full */
#define IFLS_LVL_2_8th 1 /* Interrupt at 1/4 full */
#define IFLS_LVL_4_8th 2 /* Interrupt at 1/2 full */
#define IFLS_LVL_6_8th 3 /* Interrupt at 3/4 full */
#define IFLS_LVL_7_8th 4 /* Interrupt at 7/8 full */
#define UART_IMSC 0x0e /* Interrupt mask set/clear register */
#define IMSC_MASK_ALL 0x7ff /* Mask all interrupts */
#define UART_RIS 0x0f /* Raw interrupt status register */
#define UART_RXREADY (1 << 4) /* RX buffer full */
#define UART_TXEMPTY (1 << 5) /* TX buffer empty */
#define RIS_RTIM (1 << 6) /* Receive timeout */
#define RIS_FE (1 << 7) /* Framing error interrupt status */
#define RIS_PE (1 << 8) /* Parity error interrupt status */
#define RIS_BE (1 << 9) /* Break error interrupt status */
#define RIS_OE (1 << 10) /* Overrun interrupt status */
#define UART_MIS 0x10 /* Masked interrupt status register */
#define UART_ICR 0x11 /* Interrupt clear register */
#define UART_PIDREG_0 0x3f8 /* Peripheral ID register 0 */
#define UART_PIDREG_1 0x3f9 /* Peripheral ID register 1 */
#define UART_PIDREG_2 0x3fa /* Peripheral ID register 2 */
#define UART_PIDREG_3 0x3fb /* Peripheral ID register 3 */
/*
* The hardware FIFOs are 16 bytes each on rev 2 and earlier hardware, 32 bytes
* on rev 3 and later. We configure them to interrupt when 3/4 full/empty. For
* RX we set the size to the full hardware capacity so that the uart core
* allocates enough buffer space to hold a complete fifo full of incoming data.
* For TX, we need to limit the size to the capacity we know will be available
* when the interrupt occurs; uart_core will feed exactly that many bytes to
* uart_pl011_bus_transmit() which must consume them all.
*/
#define FIFO_RX_SIZE_R2 16
#define FIFO_TX_SIZE_R2 12
#define FIFO_RX_SIZE_R3 32
#define FIFO_TX_SIZE_R3 24
#define FIFO_IFLS_BITS ((IFLS_LVL_6_8th << IFLS_RX_SHIFT) | (IFLS_LVL_2_8th))
/*
* FIXME: actual register size is SoC-dependent, we need to handle it
*/
#define __uart_getreg(bas, reg) \
bus_space_read_4((bas)->bst, (bas)->bsh, uart_regofs(bas, reg))
#define __uart_setreg(bas, reg, value) \
bus_space_write_4((bas)->bst, (bas)->bsh, uart_regofs(bas, reg), value)
/*
* Low-level UART interface.
*/
static int uart_pl011_probe(struct uart_bas *bas);
static void uart_pl011_init(struct uart_bas *bas, int, int, int, int);
static void uart_pl011_term(struct uart_bas *bas);
static void uart_pl011_putc(struct uart_bas *bas, int);
static int uart_pl011_rxready(struct uart_bas *bas);
static int uart_pl011_getc(struct uart_bas *bas, struct mtx *);
static struct uart_ops uart_pl011_ops = {
.probe = uart_pl011_probe,
.init = uart_pl011_init,
.term = uart_pl011_term,
.putc = uart_pl011_putc,
.rxready = uart_pl011_rxready,
.getc = uart_pl011_getc,
};
static int
uart_pl011_probe(struct uart_bas *bas)
{
return (0);
}
static void
uart_pl011_param(struct uart_bas *bas, int baudrate, int databits, int stopbits,
int parity)
{
uint32_t ctrl, line;
uint32_t baud;
/*
* Zero all settings to make sure
* UART is disabled and not configured
*/
ctrl = line = 0x0;
__uart_setreg(bas, UART_CR, ctrl);
/* As we know UART is disabled we may setup the line */
switch (databits) {
case 7:
line |= LCR_H_WLEN7;
break;
case 6:
line |= LCR_H_WLEN6;
break;
case 8:
default:
line |= LCR_H_WLEN8;
break;
}
if (stopbits == 2)
line |= LCR_H_STP2;
else
line &= ~LCR_H_STP2;
if (parity)
line |= LCR_H_PEN;
else
line &= ~LCR_H_PEN;
line |= LCR_H_FEN;
/* Configure the rest */
ctrl |= (CR_RXE | CR_TXE | CR_UARTEN);
if (bas->rclk != 0 && baudrate != 0) {
baud = bas->rclk * 4 / baudrate;
__uart_setreg(bas, UART_IBRD, ((uint32_t)(baud >> 6)) & IBRD_BDIVINT);
__uart_setreg(bas, UART_FBRD, (uint32_t)(baud & 0x3F) & FBRD_BDIVFRAC);
}
/* Add config. to line before reenabling UART */
__uart_setreg(bas, UART_LCR_H, (__uart_getreg(bas, UART_LCR_H) &
~0xff) | line);
/* Set rx and tx fifo levels. */
__uart_setreg(bas, UART_IFLS, FIFO_IFLS_BITS);
__uart_setreg(bas, UART_CR, ctrl);
}
static void
uart_pl011_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
int parity)
{
/* Mask all interrupts */
__uart_setreg(bas, UART_IMSC, __uart_getreg(bas, UART_IMSC) &
~IMSC_MASK_ALL);
uart_pl011_param(bas, baudrate, databits, stopbits, parity);
}
static void
uart_pl011_term(struct uart_bas *bas)
{
}
static void
uart_pl011_putc(struct uart_bas *bas, int c)
{
/* Wait when TX FIFO full. Push character otherwise. */
while (__uart_getreg(bas, UART_FR) & FR_TXFF)
;
__uart_setreg(bas, UART_DR, c & 0xff);
}
static int
uart_pl011_rxready(struct uart_bas *bas)
{
return !(__uart_getreg(bas, UART_FR) & FR_RXFE);
}
static int
uart_pl011_getc(struct uart_bas *bas, struct mtx *hwmtx)
{
int c;
while (!uart_pl011_rxready(bas))
;
c = __uart_getreg(bas, UART_DR) & 0xff;
return (c);
}
/*
* High-level UART interface.
*/
struct uart_pl011_softc {
struct uart_softc base;
uint16_t imsc; /* Interrupt mask */
};
static int uart_pl011_bus_attach(struct uart_softc *);
static int uart_pl011_bus_detach(struct uart_softc *);
static int uart_pl011_bus_flush(struct uart_softc *, int);
static int uart_pl011_bus_getsig(struct uart_softc *);
static int uart_pl011_bus_ioctl(struct uart_softc *, int, intptr_t);
static int uart_pl011_bus_ipend(struct uart_softc *);
static int uart_pl011_bus_param(struct uart_softc *, int, int, int, int);
static int uart_pl011_bus_probe(struct uart_softc *);
static int uart_pl011_bus_receive(struct uart_softc *);
static int uart_pl011_bus_setsig(struct uart_softc *, int);
static int uart_pl011_bus_transmit(struct uart_softc *);
static void uart_pl011_bus_grab(struct uart_softc *);
static void uart_pl011_bus_ungrab(struct uart_softc *);
static kobj_method_t uart_pl011_methods[] = {
KOBJMETHOD(uart_attach, uart_pl011_bus_attach),
KOBJMETHOD(uart_detach, uart_pl011_bus_detach),
KOBJMETHOD(uart_flush, uart_pl011_bus_flush),
KOBJMETHOD(uart_getsig, uart_pl011_bus_getsig),
KOBJMETHOD(uart_ioctl, uart_pl011_bus_ioctl),
KOBJMETHOD(uart_ipend, uart_pl011_bus_ipend),
KOBJMETHOD(uart_param, uart_pl011_bus_param),
KOBJMETHOD(uart_probe, uart_pl011_bus_probe),
KOBJMETHOD(uart_receive, uart_pl011_bus_receive),
KOBJMETHOD(uart_setsig, uart_pl011_bus_setsig),
KOBJMETHOD(uart_transmit, uart_pl011_bus_transmit),
KOBJMETHOD(uart_grab, uart_pl011_bus_grab),
KOBJMETHOD(uart_ungrab, uart_pl011_bus_ungrab),
{ 0, 0 }
};
static struct uart_class uart_pl011_class = {
"uart_pl011",
uart_pl011_methods,
sizeof(struct uart_pl011_softc),
.uc_ops = &uart_pl011_ops,
.uc_range = 0x48,
.uc_rclk = 0,
.uc_rshift = 2
};
#ifdef FDT
static struct ofw_compat_data fdt_compat_data[] = {
{"arm,pl011", (uintptr_t)&uart_pl011_class},
{NULL, (uintptr_t)NULL},
};
UART_FDT_CLASS_AND_DEVICE(fdt_compat_data);
#endif
#ifdef DEV_ACPI
static struct acpi_uart_compat_data acpi_compat_data[] = {
{"ARMH0011", &uart_pl011_class, ACPI_DBG2_ARM_PL011, 2, 0, 0, UART_F_IGNORE_SPCR_REGSHFT, "uart pl011"},
{"ARMH0011", &uart_pl011_class, ACPI_DBG2_ARM_SBSA_GENERIC, 2, 0, 0, UART_F_IGNORE_SPCR_REGSHFT, "uart pl011"},
{"ARMH0011", &uart_pl011_class, ACPI_DBG2_ARM_SBSA_32BIT, 2, 0, 0, UART_F_IGNORE_SPCR_REGSHFT, "uart pl011"},
{NULL, NULL, 0, 0, 0, 0, 0, NULL},
};
UART_ACPI_CLASS_AND_DEVICE(acpi_compat_data);
#endif
static int
uart_pl011_bus_attach(struct uart_softc *sc)
{
struct uart_pl011_softc *psc;
struct uart_bas *bas;
psc = (struct uart_pl011_softc *)sc;
bas = &sc->sc_bas;
/* Enable interrupts */
psc->imsc = (UART_RXREADY | RIS_RTIM | UART_TXEMPTY);
__uart_setreg(bas, UART_IMSC, psc->imsc);
/* Clear interrupts */
__uart_setreg(bas, UART_ICR, IMSC_MASK_ALL);
return (0);
}
static int
uart_pl011_bus_detach(struct uart_softc *sc)
{
return (0);
}
static int
uart_pl011_bus_flush(struct uart_softc *sc, int what)
{
return (0);
}
static int
uart_pl011_bus_getsig(struct uart_softc *sc)
{
return (0);
}
static int
uart_pl011_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
{
int error;
error = 0;
uart_lock(sc->sc_hwmtx);
switch (request) {
case UART_IOCTL_BREAK:
break;
case UART_IOCTL_BAUD:
*(int*)data = 115200;
break;
default:
error = EINVAL;
break;
}
uart_unlock(sc->sc_hwmtx);
return (error);
}
static int
uart_pl011_bus_ipend(struct uart_softc *sc)
{
struct uart_pl011_softc *psc;
struct uart_bas *bas;
uint32_t ints;
int ipend;
psc = (struct uart_pl011_softc *)sc;
bas = &sc->sc_bas;
uart_lock(sc->sc_hwmtx);
ints = __uart_getreg(bas, UART_MIS);
ipend = 0;
if (ints & (UART_RXREADY | RIS_RTIM))
ipend |= SER_INT_RXREADY;
if (ints & RIS_BE)
ipend |= SER_INT_BREAK;
if (ints & RIS_OE)
ipend |= SER_INT_OVERRUN;
if (ints & UART_TXEMPTY) {
if (sc->sc_txbusy)
ipend |= SER_INT_TXIDLE;
/* Disable TX interrupt */
__uart_setreg(bas, UART_IMSC, psc->imsc & ~UART_TXEMPTY);
}
uart_unlock(sc->sc_hwmtx);
return (ipend);
}
static int
uart_pl011_bus_param(struct uart_softc *sc, int baudrate, int databits,
int stopbits, int parity)
{
uart_lock(sc->sc_hwmtx);
uart_pl011_param(&sc->sc_bas, baudrate, databits, stopbits, parity);
uart_unlock(sc->sc_hwmtx);
return (0);
}
#ifdef FDT
static int
uart_pl011_bus_hwrev_fdt(struct uart_softc *sc)
{
pcell_t node;
uint32_t periphid;
/*
* The FIFO sizes vary depending on hardware; rev 2 and below have 16
* byte FIFOs, rev 3 and up are 32 byte. The hardware rev is in the
* primecell periphid register, but we get a bit of drama, as always,
* with the bcm2835 (rpi), which claims to be rev 3, but has 16 byte
* FIFOs. We check for both the old freebsd-historic and the proper
* bindings-defined compatible strings for bcm2835, and also check the
* workaround the linux drivers use for rpi3, which is to override the
* primecell periphid register value with a property.
*/
if (ofw_bus_is_compatible(sc->sc_dev, "brcm,bcm2835-pl011") ||
ofw_bus_is_compatible(sc->sc_dev, "broadcom,bcm2835-uart")) {
return (2);
} else {
node = ofw_bus_get_node(sc->sc_dev);
if (OF_getencprop(node, "arm,primecell-periphid", &periphid,
sizeof(periphid)) > 0) {
return ((periphid >> 20) & 0x0f);
}
}
return (-1);
}
#endif
static int
uart_pl011_bus_probe(struct uart_softc *sc)
{
int hwrev;
hwrev = -1;
#ifdef FDT
if (IS_FDT)
hwrev = uart_pl011_bus_hwrev_fdt(sc);
#endif
if (hwrev < 0)
hwrev = __uart_getreg(&sc->sc_bas, UART_PIDREG_2) >> 4;
if (hwrev <= 2) {
sc->sc_rxfifosz = FIFO_RX_SIZE_R2;
sc->sc_txfifosz = FIFO_TX_SIZE_R2;
} else {
sc->sc_rxfifosz = FIFO_RX_SIZE_R3;
sc->sc_txfifosz = FIFO_TX_SIZE_R3;
}
device_set_desc(sc->sc_dev, "PrimeCell UART (PL011)");
return (0);
}
static int
uart_pl011_bus_receive(struct uart_softc *sc)
{
struct uart_bas *bas;
uint32_t ints, xc;
int rx;
bas = &sc->sc_bas;
uart_lock(sc->sc_hwmtx);
for (;;) {
ints = __uart_getreg(bas, UART_FR);
if (ints & FR_RXFE)
break;
if (uart_rx_full(sc)) {
sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
break;
}
xc = __uart_getreg(bas, UART_DR);
rx = xc & 0xff;
if (xc & DR_FE)
rx |= UART_STAT_FRAMERR;
if (xc & DR_PE)
rx |= UART_STAT_PARERR;
uart_rx_put(sc, rx);
}
uart_unlock(sc->sc_hwmtx);
return (0);
}
static int
uart_pl011_bus_setsig(struct uart_softc *sc, int sig)
{
return (0);
}
static int
uart_pl011_bus_transmit(struct uart_softc *sc)
{
struct uart_pl011_softc *psc;
struct uart_bas *bas;
int i;
psc = (struct uart_pl011_softc *)sc;
bas = &sc->sc_bas;
uart_lock(sc->sc_hwmtx);
for (i = 0; i < sc->sc_txdatasz; i++) {
__uart_setreg(bas, UART_DR, sc->sc_txbuf[i]);
uart_barrier(bas);
}
/* Mark busy and enable TX interrupt */
sc->sc_txbusy = 1;
__uart_setreg(bas, UART_IMSC, psc->imsc);
uart_unlock(sc->sc_hwmtx);
return (0);
}
static void
uart_pl011_bus_grab(struct uart_softc *sc)
{
struct uart_pl011_softc *psc;
struct uart_bas *bas;
psc = (struct uart_pl011_softc *)sc;
bas = &sc->sc_bas;
/* Disable interrupts on switch to polling */
uart_lock(sc->sc_hwmtx);
__uart_setreg(bas, UART_IMSC, psc->imsc & ~IMSC_MASK_ALL);
uart_unlock(sc->sc_hwmtx);
}
static void
uart_pl011_bus_ungrab(struct uart_softc *sc)
{
struct uart_pl011_softc *psc;
struct uart_bas *bas;
psc = (struct uart_pl011_softc *)sc;
bas = &sc->sc_bas;
/* Switch to using interrupts while not grabbed */
uart_lock(sc->sc_hwmtx);
__uart_setreg(bas, UART_IMSC, psc->imsc);
uart_unlock(sc->sc_hwmtx);
}