From ff0d8698c2111d405e845536757e9105cfe78e8e Mon Sep 17 00:00:00 2001 From: David Hendricks Date: Thu, 28 Dec 2017 20:18:10 -0800 Subject: [PATCH] drivers/uart/pl011: Improve PL011 driver This adds a struct for registers along with some bits from ATF to the generic PL011 driver. It also adds a naive implementation of uart_tx_flush() which was previously stubbed out. Change-Id: Iee3fc6308cb92ad784e5ff3ac3a6e995d535be65 Signed-off-by: David Hendricks Reviewed-on: https://review.coreboot.org/23031 Tested-by: build bot (Jenkins) Reviewed-by: Julius Werner --- src/drivers/uart/pl011.c | 19 +++++--- src/drivers/uart/pl011.h | 94 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 106 insertions(+), 7 deletions(-) create mode 100644 src/drivers/uart/pl011.h diff --git a/src/drivers/uart/pl011.c b/src/drivers/uart/pl011.c index 709320b288..e690a9afb5 100644 --- a/src/drivers/uart/pl011.c +++ b/src/drivers/uart/pl011.c @@ -2,6 +2,7 @@ * This file is part of the coreboot project. * * Copyright (C) 2013 Google, Inc. + * Copyright 2018-present Facebook, Inc. * * This software is licensed under the terms of the GNU General Public * License version 2, as published by the Free Software Foundation, and @@ -13,13 +14,10 @@ * GNU General Public License for more details. */ +#include #include #include - -static void pl011_uart_tx_byte(unsigned int *uart_base, unsigned char data) -{ - *uart_base = (unsigned int)data; -} +#include void uart_init(int idx) { @@ -27,12 +25,19 @@ void uart_init(int idx) void uart_tx_byte(int idx, unsigned char data) { - unsigned int *uart_base = uart_platform_baseptr(idx); - pl011_uart_tx_byte(uart_base, data); + struct pl011_uart *regs = uart_platform_baseptr(idx); + + write8(®s->dr, data); + uart_tx_flush(idx); } void uart_tx_flush(int idx) { + struct pl011_uart *regs = uart_platform_baseptr(idx); + + /* FIXME: add a timeout */ + while (!(read32(®s->fr) & PL011_UARTFR_TXFE)) + ; } unsigned char uart_rx_byte(int idx) diff --git a/src/drivers/uart/pl011.h b/src/drivers/uart/pl011.h new file mode 100644 index 0000000000..9247ef7725 --- /dev/null +++ b/src/drivers/uart/pl011.h @@ -0,0 +1,94 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved. + * Copyright 2018-present Facebook, Inc. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#ifndef __DRIVERS_UART_PL011_H +#define __DRIVERS_UART_PL011_H + +#include +#include + +/* PL011 r1p5 registers */ +struct pl011_uart { + u32 dr; + u32 rsr_ecr; + u8 rsvd1[0x10]; + u32 fr; + u8 rsvd2[0x4]; + u32 ilpr; + u32 ibrd; + u32 fbrd; + u32 lcr_h; + u32 cr; + u32 ifls; + u32 imsc; + u32 ris; + u32 mis; + u32 icr; + u32 dmacr; + u8 rsvd3[0xf94]; + u32 periphid0; + u32 periphid1; + u32 periphid2; + u32 periphid3; + u32 cellid0; + u32 cellid1; + u32 cellid2; + u32 cellid3; +}; +check_member(pl011_uart, cellid3, 0xffc); + +/*************************************************************************/ +/* Bit definitions from arm-trusted-firmware/include/drivers/arm/pl011.h */ +/*************************************************************************/ +/* Flag reg bits */ +#define PL011_UARTFR_RI (1 << 8) /* Ring indicator */ +#define PL011_UARTFR_TXFE (1 << 7) /* Transmit FIFO empty */ +#define PL011_UARTFR_RXFF (1 << 6) /* Receive FIFO full */ +#define PL011_UARTFR_TXFF (1 << 5) /* Transmit FIFO full */ +#define PL011_UARTFR_RXFE (1 << 4) /* Receive FIFO empty */ +#define PL011_UARTFR_BUSY (1 << 3) /* UART busy */ +#define PL011_UARTFR_DCD (1 << 2) /* Data carrier detect */ +#define PL011_UARTFR_DSR (1 << 1) /* Data set ready */ +#define PL011_UARTFR_CTS (1 << 0) /* Clear to send */ + +#define PL011_UARTFR_TXFF_BIT 5 /* Transmit FIFO full bit in + UARTFR register */ +#define PL011_UARTFR_RXFE_BIT 4 /* Receive FIFO empty bit in + UARTFR register */ +#define PL011_UARTFR_BUSY_BIT 3 /* UART busy bit in UARTFR + register */ + +/* Control reg bits */ +#define PL011_UARTCR_CTSEN (1 << 15) /* CTS hardware flow control + enable */ +#define PL011_UARTCR_RTSEN (1 << 14) /* RTS hardware flow control + enable */ +#define PL011_UARTCR_RTS (1 << 11) /* Request to send */ +#define PL011_UARTCR_DTR (1 << 10) /* Data transmit ready. */ +#define PL011_UARTCR_RXE (1 << 9) /* Receive enable */ +#define PL011_UARTCR_TXE (1 << 8) /* Transmit enable */ +#define PL011_UARTCR_LBE (1 << 7) /* Loopback enable */ +#define PL011_UARTCR_UARTEN (1 << 0) /* UART Enable */ + +/* FIFO Enabled / No Parity / 8 Data bit / One Stop Bit */ +#define PL011_LINE_CONTROL (PL011_UARTLCR_H_FEN | PL011_UARTLCR_H_WLEN_8) + +/* Line Control Register Bits */ +#define PL011_UARTLCR_H_SPS (1 << 7) /* Stick parity select */ +#define PL011_UARTLCR_H_WLEN_8 (3 << 5) +#define PL011_UARTLCR_H_WLEN_7 (2 << 5) +#define PL011_UARTLCR_H_WLEN_6 (1 << 5) +#define PL011_UARTLCR_H_WLEN_5 (0 << 5) +#define PL011_UARTLCR_H_FEN (1 << 4) /* FIFOs Enable */ +#define PL011_UARTLCR_H_STP2 (1 << 3) /* Two stop bits select */ +#define PL011_UARTLCR_H_EPS (1 << 2) /* Even parity select */ +#define PL011_UARTLCR_H_PEN (1 << 1) /* Parity Enable */ +#define PL011_UARTLCR_H_BRK (1 << 0) /* Send break */ + +#endif /* ! __DRIVERS_UART_PL011_H */