diff options
Diffstat (limited to 'drivers/tty/serial/serial-tegra.c')
| -rw-r--r-- | drivers/tty/serial/serial-tegra.c | 960 |
1 files changed, 632 insertions, 328 deletions
diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c index ee7c8123c374..8004fc00fb9c 100644 --- a/drivers/tty/serial/serial-tegra.c +++ b/drivers/tty/serial/serial-tegra.c @@ -1,23 +1,12 @@ +// SPDX-License-Identifier: GPL-2.0 /* * serial_tegra.c * * High-speed serial driver for NVIDIA Tegra SoCs * - * Copyright (c) 2012-2013, NVIDIA CORPORATION. All rights reserved. + * Copyright (c) 2012-2019, NVIDIA CORPORATION. All rights reserved. * * Author: Laxman Dewangan <ldewangan@nvidia.com> - * - * This program is free software; you can redistribute it and/or modify it - * under the terms and conditions of the GNU General Public License, - * version 2, as published by the Free Software Foundation. - * - * This program is distributed in the hope it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for - * more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <linux/clk.h> @@ -31,9 +20,9 @@ #include <linux/irq.h> #include <linux/module.h> #include <linux/of.h> -#include <linux/of_device.h> #include <linux/pagemap.h> #include <linux/platform_device.h> +#include <linux/reset.h> #include <linux/serial.h> #include <linux/serial_8250.h> #include <linux/serial_core.h> @@ -44,8 +33,6 @@ #include <linux/tty.h> #include <linux/tty_flip.h> -#include <linux/clk/tegra.h> - #define TEGRA_UART_TYPE "TEGRA_UART" #define TX_EMPTY_STATUS (UART_LSR_TEMT | UART_LSR_THRE) #define BYTES_TO_ALIGN(x) ((unsigned long)(x) & 0x3) @@ -74,7 +61,7 @@ #define TEGRA_UART_TX_TRIG_4B 0x20 #define TEGRA_UART_TX_TRIG_1B 0x30 -#define TEGRA_UART_MAXIMUM 5 +#define TEGRA_UART_MAXIMUM 8 /* Default UART setting when started: 115200 no parity, stop, 8 data bits */ #define TEGRA_UART_DEFAULT_BAUD 115200 @@ -84,18 +71,36 @@ #define TEGRA_TX_PIO 1 #define TEGRA_TX_DMA 2 +#define TEGRA_UART_FCR_IIR_FIFO_EN 0x40 + /** - * tegra_uart_chip_data: SOC specific data. + * struct tegra_uart_chip_data: SOC specific data. * * @tx_fifo_full_status: Status flag available for checking tx fifo full. * @allow_txfifo_reset_fifo_mode: allow_tx fifo reset with fifo mode or not. * Tegra30 does not allow this. * @support_clk_src_div: Clock source support the clock divider. + * @fifo_mode_enable_status: Is FIFO mode enabled? + * @uart_max_port: Maximum number of UART ports + * @max_dma_burst_bytes: Maximum size of DMA bursts + * @error_tolerance_low_range: Lowest number in the error tolerance range + * @error_tolerance_high_range: Highest number in the error tolerance range */ struct tegra_uart_chip_data { bool tx_fifo_full_status; bool allow_txfifo_reset_fifo_mode; bool support_clk_src_div; + bool fifo_mode_enable_status; + int uart_max_port; + int max_dma_burst_bytes; + int error_tolerance_low_range; + int error_tolerance_high_range; +}; + +struct tegra_baud_tolerance { + u32 lower_range_baud; + u32 upper_range_baud; + s32 tolerance; }; struct tegra_uart_port { @@ -103,6 +108,7 @@ struct tegra_uart_port { const struct tegra_uart_chip_data *cdata; struct clk *uart_clk; + struct reset_control *rst; unsigned int current_baud; /* Register shadow */ @@ -120,7 +126,6 @@ struct tegra_uart_port { bool rx_timeout; int rx_in_progress; int symb_bit; - int dma_req_sel; struct dma_chan *rx_dma_chan; struct dma_chan *tx_dma_chan; @@ -132,12 +137,21 @@ struct tegra_uart_port { struct dma_async_tx_descriptor *rx_dma_desc; dma_cookie_t tx_cookie; dma_cookie_t rx_cookie; - int tx_bytes_requested; - int rx_bytes_requested; + unsigned int tx_bytes_requested; + unsigned int rx_bytes_requested; + struct tegra_baud_tolerance *baud_tolerance; + int n_adjustable_baud_rates; + int required_rate; + int configured_rate; + bool use_rx_pio; + bool use_tx_pio; + bool rx_dma_active; }; static void tegra_uart_start_next_tx(struct tegra_uart_port *tup); static int tegra_uart_start_rx_dma(struct tegra_uart_port *tup); +static void tegra_uart_dma_channel_free(struct tegra_uart_port *tup, + bool dma_to_memory); static inline unsigned long tegra_uart_read(struct tegra_uart_port *tup, unsigned long reg) @@ -187,7 +201,6 @@ static void set_rts(struct tegra_uart_port *tup, bool active) tegra_uart_write(tup, mcr, UART_MCR); tup->mcr_shadow = mcr; } - return; } static void set_dtr(struct tegra_uart_port *tup, bool active) @@ -203,22 +216,36 @@ static void set_dtr(struct tegra_uart_port *tup, bool active) tegra_uart_write(tup, mcr, UART_MCR); tup->mcr_shadow = mcr; } - return; +} + +static void set_loopbk(struct tegra_uart_port *tup, bool active) +{ + unsigned long mcr = tup->mcr_shadow; + + if (active) + mcr |= UART_MCR_LOOP; + else + mcr &= ~UART_MCR_LOOP; + + if (mcr != tup->mcr_shadow) { + tegra_uart_write(tup, mcr, UART_MCR); + tup->mcr_shadow = mcr; + } } static void tegra_uart_set_mctrl(struct uart_port *u, unsigned int mctrl) { struct tegra_uart_port *tup = to_tegra_uport(u); - unsigned long mcr; - int dtr_enable; + int enable; - mcr = tup->mcr_shadow; tup->rts_active = !!(mctrl & TIOCM_RTS); set_rts(tup, tup->rts_active); - dtr_enable = !!(mctrl & TIOCM_DTR); - set_dtr(tup, dtr_enable); - return; + enable = !!(mctrl & TIOCM_DTR); + set_dtr(tup, enable); + + enable = !!(mctrl & TIOCM_LOOP); + set_loopbk(tup, enable); } static void tegra_uart_break_ctl(struct uart_port *u, int break_ctl) @@ -235,6 +262,22 @@ static void tegra_uart_break_ctl(struct uart_port *u, int break_ctl) tup->lcr_shadow = lcr; } +/** + * tegra_uart_wait_cycle_time: Wait for N UART clock periods + * + * @tup: Tegra serial port data structure. + * @cycles: Number of clock periods to wait. + * + * Tegra UARTs are clocked at 16X the baud/bit rate and hence the UART + * clock speed is 16X the current baud rate. + */ +static void tegra_uart_wait_cycle_time(struct tegra_uart_port *tup, + unsigned int cycles) +{ + if (tup->current_baud) + udelay(DIV_ROUND_UP(cycles * 1000000, tup->current_baud * 16)); +} + /* Wait for a symbol-time. */ static void tegra_uart_wait_sym_time(struct tegra_uart_port *tup, unsigned int syms) @@ -244,9 +287,28 @@ static void tegra_uart_wait_sym_time(struct tegra_uart_port *tup, tup->current_baud)); } +static int tegra_uart_wait_fifo_mode_enabled(struct tegra_uart_port *tup) +{ + unsigned long iir; + unsigned int tmout = 100; + + do { + iir = tegra_uart_read(tup, UART_IIR); + if (iir & TEGRA_UART_FCR_IIR_FIFO_EN) + return 0; + udelay(1); + } while (--tmout); + + return -ETIMEDOUT; +} + static void tegra_uart_fifo_reset(struct tegra_uart_port *tup, u8 fcr_bits) { unsigned long fcr = tup->fcr_shadow; + unsigned int lsr, tmout = 10000; + + if (tup->rts_active) + set_rts(tup, false); if (tup->cdata->allow_txfifo_reset_fifo_mode) { fcr |= fcr_bits & (UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); @@ -259,13 +321,60 @@ static void tegra_uart_fifo_reset(struct tegra_uart_port *tup, u8 fcr_bits) tegra_uart_write(tup, fcr, UART_FCR); fcr |= UART_FCR_ENABLE_FIFO; tegra_uart_write(tup, fcr, UART_FCR); + if (tup->cdata->fifo_mode_enable_status) + tegra_uart_wait_fifo_mode_enabled(tup); } /* Dummy read to ensure the write is posted */ tegra_uart_read(tup, UART_SCR); - /* Wait for the flush to propagate. */ - tegra_uart_wait_sym_time(tup, 1); + /* + * For all tegra devices (up to t210), there is a hardware issue that + * requires software to wait for 32 UART clock periods for the flush + * to propagate, otherwise data could be lost. + */ + tegra_uart_wait_cycle_time(tup, 32); + + do { + lsr = tegra_uart_read(tup, UART_LSR); + if ((lsr & UART_LSR_TEMT) && !(lsr & UART_LSR_DR)) + break; + udelay(1); + } while (--tmout); + + if (tup->rts_active) + set_rts(tup, true); +} + +static long tegra_get_tolerance_rate(struct tegra_uart_port *tup, + unsigned int baud, long rate) +{ + int i; + + for (i = 0; i < tup->n_adjustable_baud_rates; ++i) { + if (baud >= tup->baud_tolerance[i].lower_range_baud && + baud <= tup->baud_tolerance[i].upper_range_baud) + return (rate + (rate * + tup->baud_tolerance[i].tolerance) / 10000); + } + + return rate; +} + +static int tegra_check_rate_in_range(struct tegra_uart_port *tup) +{ + long diff; + + diff = ((long)(tup->configured_rate - tup->required_rate) * 10000) + / tup->required_rate; + if (diff < (tup->cdata->error_tolerance_low_range * 100) || + diff > (tup->cdata->error_tolerance_high_range * 100)) { + dev_err(tup->uport.dev, + "configured baud rate is out of range by %ld", diff); + return -EIO; + } + + return 0; } static int tegra_set_baudrate(struct tegra_uart_port *tup, unsigned int baud) @@ -273,6 +382,7 @@ static int tegra_set_baudrate(struct tegra_uart_port *tup, unsigned int baud) unsigned long rate; unsigned int divisor; unsigned long lcr; + unsigned long flags; int ret; if (tup->current_baud == baud) @@ -280,18 +390,28 @@ static int tegra_set_baudrate(struct tegra_uart_port *tup, unsigned int baud) if (tup->cdata->support_clk_src_div) { rate = baud * 16; + tup->required_rate = rate; + + if (tup->n_adjustable_baud_rates) + rate = tegra_get_tolerance_rate(tup, baud, rate); + ret = clk_set_rate(tup->uart_clk, rate); if (ret < 0) { dev_err(tup->uport.dev, "clk_set_rate() failed for rate %lu\n", rate); return ret; } + tup->configured_rate = clk_get_rate(tup->uart_clk); divisor = 1; + ret = tegra_check_rate_in_range(tup); + if (ret < 0) + return ret; } else { rate = clk_get_rate(tup->uart_clk); divisor = DIV_ROUND_CLOSEST(rate, baud * 16); } + uart_port_lock_irqsave(&tup->uport, &flags); lcr = tup->lcr_shadow; lcr |= UART_LCR_DLAB; tegra_uart_write(tup, lcr, UART_LCR); @@ -304,6 +424,7 @@ static int tegra_set_baudrate(struct tegra_uart_port *tup, unsigned int baud) /* Dummy read to ensure the write is posted */ tegra_uart_read(tup, UART_SCR); + uart_port_unlock_irqrestore(&tup->uport, flags); tup->current_baud = baud; @@ -312,34 +433,42 @@ static int tegra_set_baudrate(struct tegra_uart_port *tup, unsigned int baud) return 0; } -static char tegra_uart_decode_rx_error(struct tegra_uart_port *tup, +static u8 tegra_uart_decode_rx_error(struct tegra_uart_port *tup, unsigned long lsr) { - char flag = TTY_NORMAL; + u8 flag = TTY_NORMAL; if (unlikely(lsr & TEGRA_UART_LSR_ANY)) { if (lsr & UART_LSR_OE) { - /* Overrrun error */ - flag |= TTY_OVERRUN; + /* Overrun error */ + flag = TTY_OVERRUN; tup->uport.icount.overrun++; - dev_err(tup->uport.dev, "Got overrun errors\n"); + dev_dbg(tup->uport.dev, "Got overrun errors\n"); } else if (lsr & UART_LSR_PE) { /* Parity error */ - flag |= TTY_PARITY; + flag = TTY_PARITY; tup->uport.icount.parity++; - dev_err(tup->uport.dev, "Got Parity errors\n"); + dev_dbg(tup->uport.dev, "Got Parity errors\n"); } else if (lsr & UART_LSR_FE) { - flag |= TTY_FRAME; + flag = TTY_FRAME; tup->uport.icount.frame++; - dev_err(tup->uport.dev, "Got frame errors\n"); + dev_dbg(tup->uport.dev, "Got frame errors\n"); } else if (lsr & UART_LSR_BI) { - dev_err(tup->uport.dev, "Got Break\n"); - tup->uport.icount.brk++; - /* If FIFO read error without any data, reset Rx FIFO */ + /* + * Break error + * If FIFO read error without any data, reset Rx FIFO + */ if (!(lsr & UART_LSR_DR) && (lsr & UART_LSR_FIFOE)) tegra_uart_fifo_reset(tup, UART_FCR_CLEAR_RCVR); + if (tup->uport.ignore_status_mask & UART_LSR_BI) + return TTY_BREAK; + flag = TTY_BREAK; + tup->uport.icount.brk++; + dev_dbg(tup->uport.dev, "Got Break\n"); } + uart_insert_char(&tup->uport, lsr, UART_LSR_OE, 0, flag); } + return flag; } @@ -355,19 +484,18 @@ static void tegra_uart_release_port(struct uart_port *u) static void tegra_uart_fill_tx_fifo(struct tegra_uart_port *tup, int max_bytes) { - struct circ_buf *xmit = &tup->uport.state->xmit; + unsigned char ch; int i; for (i = 0; i < max_bytes; i++) { - BUG_ON(uart_circ_empty(xmit)); if (tup->cdata->tx_fifo_full_status) { unsigned long lsr = tegra_uart_read(tup, UART_LSR); if ((lsr & TEGRA_UART_LSR_TXFIFO_FULL)) break; } - tegra_uart_write(tup, xmit->buf[xmit->tail], UART_TX); - xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - tup->uport.icount.tx++; + if (WARN_ON_ONCE(!uart_fifo_get(&tup->uport, &ch))) + break; + tegra_uart_write(tup, ch, UART_TX); } } @@ -386,34 +514,38 @@ static void tegra_uart_start_pio_tx(struct tegra_uart_port *tup, static void tegra_uart_tx_dma_complete(void *args) { struct tegra_uart_port *tup = args; - struct circ_buf *xmit = &tup->uport.state->xmit; + struct tty_port *tport = &tup->uport.state->port; struct dma_tx_state state; unsigned long flags; - int count; + unsigned int count; - dmaengine_tx_status(tup->tx_dma_chan, tup->rx_cookie, &state); + dmaengine_tx_status(tup->tx_dma_chan, tup->tx_cookie, &state); count = tup->tx_bytes_requested - state.residue; async_tx_ack(tup->tx_dma_desc); - spin_lock_irqsave(&tup->uport.lock, flags); - xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1); + uart_port_lock_irqsave(&tup->uport, &flags); + uart_xmit_advance(&tup->uport, count); tup->tx_in_progress = 0; - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) uart_write_wakeup(&tup->uport); tegra_uart_start_next_tx(tup); - spin_unlock_irqrestore(&tup->uport.lock, flags); + uart_port_unlock_irqrestore(&tup->uport, flags); } static int tegra_uart_start_tx_dma(struct tegra_uart_port *tup, unsigned long count) { - struct circ_buf *xmit = &tup->uport.state->xmit; + struct tty_port *tport = &tup->uport.state->port; dma_addr_t tx_phys_addr; - - dma_sync_single_for_device(tup->uport.dev, tup->tx_dma_buf_phys, - UART_XMIT_SIZE, DMA_TO_DEVICE); + unsigned int tail; tup->tx_bytes = count & ~(0xF); - tx_phys_addr = tup->tx_dma_buf_phys + xmit->tail; + WARN_ON_ONCE(kfifo_out_linear(&tport->xmit_fifo, &tail, + UART_XMIT_SIZE) < count); + tx_phys_addr = tup->tx_dma_buf_phys + tail; + + dma_sync_single_for_device(tup->uport.dev, tx_phys_addr, + tup->tx_bytes, DMA_TO_DEVICE); + tup->tx_dma_desc = dmaengine_prep_slave_single(tup->tx_dma_chan, tx_phys_addr, tup->tx_bytes, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT); @@ -433,16 +565,22 @@ static int tegra_uart_start_tx_dma(struct tegra_uart_port *tup, static void tegra_uart_start_next_tx(struct tegra_uart_port *tup) { + struct tty_port *tport = &tup->uport.state->port; + unsigned char *tail_ptr; unsigned long tail; - unsigned long count; - struct circ_buf *xmit = &tup->uport.state->xmit; + unsigned int count; + + if (!tup->current_baud) + return; - tail = (unsigned long)&xmit->buf[xmit->tail]; - count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); + count = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail_ptr, + UART_XMIT_SIZE); if (!count) return; - if (count < TEGRA_UART_MIN_DMA) + tail = (unsigned long)tail_ptr; + + if (tup->use_tx_pio || count < TEGRA_UART_MIN_DMA) tegra_uart_start_pio_tx(tup, count); else if (BYTES_TO_ALIGN(tail) > 0) tegra_uart_start_pio_tx(tup, BYTES_TO_ALIGN(tail)); @@ -454,9 +592,9 @@ static void tegra_uart_start_next_tx(struct tegra_uart_port *tup) static void tegra_uart_start_tx(struct uart_port *u) { struct tegra_uart_port *tup = to_tegra_uport(u); - struct circ_buf *xmit = &u->state->xmit; + struct tty_port *tport = &u->state->port; - if (!uart_circ_empty(xmit) && !tup->tx_in_progress) + if (!kfifo_is_empty(&tport->xmit_fifo) && !tup->tx_in_progress) tegra_uart_start_next_tx(tup); } @@ -466,148 +604,184 @@ static unsigned int tegra_uart_tx_empty(struct uart_port *u) unsigned int ret = 0; unsigned long flags; - spin_lock_irqsave(&u->lock, flags); + uart_port_lock_irqsave(u, &flags); if (!tup->tx_in_progress) { unsigned long lsr = tegra_uart_read(tup, UART_LSR); if ((lsr & TX_EMPTY_STATUS) == TX_EMPTY_STATUS) ret = TIOCSER_TEMT; } - spin_unlock_irqrestore(&u->lock, flags); + uart_port_unlock_irqrestore(u, flags); return ret; } static void tegra_uart_stop_tx(struct uart_port *u) { struct tegra_uart_port *tup = to_tegra_uport(u); - struct circ_buf *xmit = &tup->uport.state->xmit; struct dma_tx_state state; - int count; + unsigned int count; - dmaengine_terminate_all(tup->tx_dma_chan); + if (tup->tx_in_progress != TEGRA_UART_TX_DMA) + return; + + dmaengine_pause(tup->tx_dma_chan); dmaengine_tx_status(tup->tx_dma_chan, tup->tx_cookie, &state); + dmaengine_terminate_all(tup->tx_dma_chan); count = tup->tx_bytes_requested - state.residue; async_tx_ack(tup->tx_dma_desc); - xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1); + uart_xmit_advance(&tup->uport, count); tup->tx_in_progress = 0; - return; } static void tegra_uart_handle_tx_pio(struct tegra_uart_port *tup) { - struct circ_buf *xmit = &tup->uport.state->xmit; + struct tty_port *tport = &tup->uport.state->port; tegra_uart_fill_tx_fifo(tup, tup->tx_bytes); tup->tx_in_progress = 0; - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) uart_write_wakeup(&tup->uport); tegra_uart_start_next_tx(tup); - return; } static void tegra_uart_handle_rx_pio(struct tegra_uart_port *tup, - struct tty_port *tty) + struct tty_port *port) { do { - char flag = TTY_NORMAL; unsigned long lsr = 0; - unsigned char ch; + u8 ch, flag = TTY_NORMAL; lsr = tegra_uart_read(tup, UART_LSR); if (!(lsr & UART_LSR_DR)) break; flag = tegra_uart_decode_rx_error(tup, lsr); + if (flag != TTY_NORMAL) + continue; + ch = (unsigned char) tegra_uart_read(tup, UART_RX); tup->uport.icount.rx++; - if (!uart_handle_sysrq_char(&tup->uport, ch) && tty) - tty_insert_flip_char(tty, ch, flag); - } while (1); + if (uart_handle_sysrq_char(&tup->uport, ch)) + continue; - return; + if (tup->uport.ignore_status_mask & UART_LSR_DR) + continue; + + tty_insert_flip_char(port, ch, flag); + } while (1); } static void tegra_uart_copy_rx_to_tty(struct tegra_uart_port *tup, - struct tty_port *tty, int count) + struct tty_port *port, + unsigned int count) { int copied; + /* If count is zero, then there is no data to be copied */ + if (!count) + return; + tup->uport.icount.rx += count; - if (!tty) { - dev_err(tup->uport.dev, "No tty port\n"); + + if (tup->uport.ignore_status_mask & UART_LSR_DR) return; - } + dma_sync_single_for_cpu(tup->uport.dev, tup->rx_dma_buf_phys, - TEGRA_UART_RX_DMA_BUFFER_SIZE, DMA_FROM_DEVICE); - copied = tty_insert_flip_string(tty, + count, DMA_FROM_DEVICE); + copied = tty_insert_flip_string(port, ((unsigned char *)(tup->rx_dma_buf_virt)), count); if (copied != count) { WARN_ON(1); dev_err(tup->uport.dev, "RxData copy to tty layer failed\n"); } dma_sync_single_for_device(tup->uport.dev, tup->rx_dma_buf_phys, - TEGRA_UART_RX_DMA_BUFFER_SIZE, DMA_TO_DEVICE); + count, DMA_TO_DEVICE); +} + +static void do_handle_rx_pio(struct tegra_uart_port *tup) +{ + struct tty_struct *tty = tty_port_tty_get(&tup->uport.state->port); + struct tty_port *port = &tup->uport.state->port; + + tegra_uart_handle_rx_pio(tup, port); + if (tty) { + tty_flip_buffer_push(port); + tty_kref_put(tty); + } +} + +static void tegra_uart_rx_buffer_push(struct tegra_uart_port *tup, + unsigned int residue) +{ + struct tty_port *port = &tup->uport.state->port; + unsigned int count; + + async_tx_ack(tup->rx_dma_desc); + count = tup->rx_bytes_requested - residue; + + /* If we are here, DMA is stopped */ + tegra_uart_copy_rx_to_tty(tup, port, count); + + do_handle_rx_pio(tup); } static void tegra_uart_rx_dma_complete(void *args) { struct tegra_uart_port *tup = args; struct uart_port *u = &tup->uport; - int count = tup->rx_bytes_requested; - struct tty_struct *tty = tty_port_tty_get(&tup->uport.state->port); - struct tty_port *port = &u->state->port; unsigned long flags; + struct dma_tx_state state; + enum dma_status status; - async_tx_ack(tup->rx_dma_desc); - spin_lock_irqsave(&u->lock, flags); + uart_port_lock_irqsave(u, &flags); + + status = dmaengine_tx_status(tup->rx_dma_chan, tup->rx_cookie, &state); + + if (status == DMA_IN_PROGRESS) { + dev_dbg(tup->uport.dev, "RX DMA is in progress\n"); + goto done; + } /* Deactivate flow control to stop sender */ if (tup->rts_active) set_rts(tup, false); - /* If we are here, DMA is stopped */ - if (count) - tegra_uart_copy_rx_to_tty(tup, port, count); - - tegra_uart_handle_rx_pio(tup, port); - if (tty) { - tty_flip_buffer_push(port); - tty_kref_put(tty); - } + tup->rx_dma_active = false; + tegra_uart_rx_buffer_push(tup, 0); tegra_uart_start_rx_dma(tup); /* Activate flow control to start transfer */ if (tup->rts_active) set_rts(tup, true); - spin_unlock_irqrestore(&u->lock, flags); +done: + uart_port_unlock_irqrestore(u, flags); } -static void tegra_uart_handle_rx_dma(struct tegra_uart_port *tup) +static void tegra_uart_terminate_rx_dma(struct tegra_uart_port *tup) { struct dma_tx_state state; - struct tty_struct *tty = tty_port_tty_get(&tup->uport.state->port); - struct tty_port *port = &tup->uport.state->port; - int count; - /* Deactivate flow control to stop sender */ - if (tup->rts_active) - set_rts(tup, false); + if (!tup->rx_dma_active) { + do_handle_rx_pio(tup); + return; + } + dmaengine_pause(tup->rx_dma_chan); + dmaengine_tx_status(tup->rx_dma_chan, tup->rx_cookie, &state); dmaengine_terminate_all(tup->rx_dma_chan); - dmaengine_tx_status(tup->rx_dma_chan, tup->rx_cookie, &state); - count = tup->rx_bytes_requested - state.residue; - /* If we are here, DMA is stopped */ - if (count) - tegra_uart_copy_rx_to_tty(tup, port, count); + tegra_uart_rx_buffer_push(tup, state.residue); + tup->rx_dma_active = false; +} - tegra_uart_handle_rx_pio(tup, port); - if (tty) { - tty_flip_buffer_push(port); - tty_kref_put(tty); - } - tegra_uart_start_rx_dma(tup); +static void tegra_uart_handle_rx_dma(struct tegra_uart_port *tup) +{ + /* Deactivate flow control to stop sender */ + if (tup->rts_active) + set_rts(tup, false); + + tegra_uart_terminate_rx_dma(tup); if (tup->rts_active) set_rts(tup, true); @@ -617,6 +791,9 @@ static int tegra_uart_start_rx_dma(struct tegra_uart_port *tup) { unsigned int count = TEGRA_UART_RX_DMA_BUFFER_SIZE; + if (tup->rx_dma_active) + return 0; + tup->rx_dma_desc = dmaengine_prep_slave_single(tup->rx_dma_chan, tup->rx_dma_buf_phys, count, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT); @@ -625,10 +802,9 @@ static int tegra_uart_start_rx_dma(struct tegra_uart_port *tup) return -EIO; } + tup->rx_dma_active = true; tup->rx_dma_desc->callback = tegra_uart_rx_dma_complete; tup->rx_dma_desc->callback_param = tup; - dma_sync_single_for_device(tup->uport.dev, tup->rx_dma_buf_phys, - count, DMA_TO_DEVICE); tup->rx_bytes_requested = count; tup->rx_cookie = dmaengine_submit(tup->rx_dma_desc); dma_async_issue_pending(tup->rx_dma_chan); @@ -654,7 +830,6 @@ static void tegra_uart_handle_modem_signal_change(struct uart_port *u) /* Will start/stop_tx accordingly */ if (msr & UART_MSR_DCTS) uart_handle_cts_change(&tup->uport, msr & UART_MSR_CTS); - return; } static irqreturn_t tegra_uart_isr(int irq, void *data) @@ -663,24 +838,27 @@ static irqreturn_t tegra_uart_isr(int irq, void *data) struct uart_port *u = &tup->uport; unsigned long iir; unsigned long ier; + bool is_rx_start = false; bool is_rx_int = false; unsigned long flags; - spin_lock_irqsave(&u->lock, flags); + uart_port_lock_irqsave(u, &flags); while (1) { iir = tegra_uart_read(tup, UART_IIR); if (iir & UART_IIR_NO_INT) { - if (is_rx_int) { + if (!tup->use_rx_pio && is_rx_int) { tegra_uart_handle_rx_dma(tup); if (tup->rx_in_progress) { ier = tup->ier_shadow; ier |= (UART_IER_RLSI | UART_IER_RTOIE | - TEGRA_UART_IER_EORD); + TEGRA_UART_IER_EORD | UART_IER_RDI); tup->ier_shadow = ier; tegra_uart_write(tup, ier, UART_IER); } + } else if (is_rx_start) { + tegra_uart_start_rx_dma(tup); } - spin_unlock_irqrestore(&u->lock, flags); + uart_port_unlock_irqrestore(u, flags); return IRQ_HANDLED; } @@ -697,17 +875,25 @@ static irqreturn_t tegra_uart_isr(int irq, void *data) case 4: /* End of data */ case 6: /* Rx timeout */ - case 2: /* Receive */ - if (!is_rx_int) { - is_rx_int = true; + if (!tup->use_rx_pio) { + is_rx_int = tup->rx_in_progress; /* Disable Rx interrupts */ ier = tup->ier_shadow; - ier |= UART_IER_RDI; - tegra_uart_write(tup, ier, UART_IER); ier &= ~(UART_IER_RDI | UART_IER_RLSI | UART_IER_RTOIE | TEGRA_UART_IER_EORD); tup->ier_shadow = ier; tegra_uart_write(tup, ier, UART_IER); + break; + } + fallthrough; + case 2: /* Receive */ + if (!tup->use_rx_pio) { + is_rx_start = tup->rx_in_progress; + tup->ier_shadow &= ~UART_IER_RDI; + tegra_uart_write(tup, tup->ier_shadow, + UART_IER); + } else { + do_handle_rx_pio(tup); } break; @@ -726,11 +912,8 @@ static irqreturn_t tegra_uart_isr(int irq, void *data) static void tegra_uart_stop_rx(struct uart_port *u) { struct tegra_uart_port *tup = to_tegra_uport(u); - struct tty_struct *tty = tty_port_tty_get(&tup->uport.state->port); - struct tty_port *port = &u->state->port; - struct dma_tx_state state; + struct tty_port *port = &tup->uport.state->port; unsigned long ier; - int count; if (tup->rts_active) set_rts(tup, false); @@ -738,7 +921,7 @@ static void tegra_uart_stop_rx(struct uart_port *u) if (!tup->rx_in_progress) return; - tegra_uart_wait_sym_time(tup, 1); /* wait a character interval */ + tegra_uart_wait_sym_time(tup, 1); /* wait one character interval */ ier = tup->ier_shadow; ier &= ~(UART_IER_RDI | UART_IER_RLSI | UART_IER_RTOIE | @@ -746,21 +929,11 @@ static void tegra_uart_stop_rx(struct uart_port *u) tup->ier_shadow = ier; tegra_uart_write(tup, ier, UART_IER); tup->rx_in_progress = 0; - if (tup->rx_dma_chan) { - dmaengine_terminate_all(tup->rx_dma_chan); - dmaengine_tx_status(tup->rx_dma_chan, tup->rx_cookie, &state); - async_tx_ack(tup->rx_dma_desc); - count = tup->rx_bytes_requested - state.residue; - tegra_uart_copy_rx_to_tty(tup, port, count); - tegra_uart_handle_rx_pio(tup, port); - } else { + + if (!tup->use_rx_pio) + tegra_uart_terminate_rx_dma(tup); + else tegra_uart_handle_rx_pio(tup, port); - } - if (tty) { - tty_flip_buffer_push(port); - tty_kref_put(tty); - } - return; } static void tegra_uart_hw_deinit(struct tegra_uart_port *tup) @@ -802,11 +975,19 @@ static void tegra_uart_hw_deinit(struct tegra_uart_port *tup) } } - spin_lock_irqsave(&tup->uport.lock, flags); + uart_port_lock_irqsave(&tup->uport, &flags); /* Reset the Rx and Tx FIFOs */ tegra_uart_fifo_reset(tup, UART_FCR_CLEAR_XMIT | UART_FCR_CLEAR_RCVR); tup->current_baud = 0; - spin_unlock_irqrestore(&tup->uport.lock, flags); + uart_port_unlock_irqrestore(&tup->uport, flags); + + tup->rx_in_progress = 0; + tup->tx_in_progress = 0; + + if (!tup->use_rx_pio) + tegra_uart_dma_channel_free(tup, true); + if (!tup->use_tx_pio) + tegra_uart_dma_channel_free(tup, false); clk_disable_unprepare(tup->uart_clk); } @@ -821,12 +1002,16 @@ static int tegra_uart_hw_init(struct tegra_uart_port *tup) tup->ier_shadow = 0; tup->current_baud = 0; - clk_prepare_enable(tup->uart_clk); + ret = clk_prepare_enable(tup->uart_clk); + if (ret) { + dev_err(tup->uport.dev, "could not enable clk\n"); + return ret; + } /* Reset the UART controller to clear all previous status.*/ - tegra_periph_reset_assert(tup->uart_clk); + reset_control_assert(tup->rst); udelay(10); - tegra_periph_reset_deassert(tup->uart_clk); + reset_control_deassert(tup->rst); tup->rx_in_progress = 0; tup->tx_in_progress = 0; @@ -850,38 +1035,67 @@ static int tegra_uart_hw_init(struct tegra_uart_port *tup) * programmed in the DMA registers. */ tup->fcr_shadow = UART_FCR_ENABLE_FIFO; - tup->fcr_shadow |= UART_FCR_R_TRIG_01; + + if (tup->use_rx_pio) { + tup->fcr_shadow |= UART_FCR_R_TRIG_11; + } else { + if (tup->cdata->max_dma_burst_bytes == 8) + tup->fcr_shadow |= UART_FCR_R_TRIG_10; + else + tup->fcr_shadow |= UART_FCR_R_TRIG_01; + } + tup->fcr_shadow |= TEGRA_UART_TX_TRIG_16B; tegra_uart_write(tup, tup->fcr_shadow, UART_FCR); + /* Dummy read to ensure the write is posted */ + tegra_uart_read(tup, UART_SCR); + + if (tup->cdata->fifo_mode_enable_status) { + ret = tegra_uart_wait_fifo_mode_enabled(tup); + if (ret < 0) { + clk_disable_unprepare(tup->uart_clk); + dev_err(tup->uport.dev, + "Failed to enable FIFO mode: %d\n", ret); + return ret; + } + } else { + /* + * For all tegra devices (up to t210), there is a hardware + * issue that requires software to wait for 3 UART clock + * periods after enabling the TX fifo, otherwise data could + * be lost. + */ + tegra_uart_wait_cycle_time(tup, 3); + } + /* * Initialize the UART with default configuration * (115200, N, 8, 1) so that the receive DMA buffer may be * enqueued */ - tup->lcr_shadow = TEGRA_UART_DEFAULT_LSR; - tegra_set_baudrate(tup, TEGRA_UART_DEFAULT_BAUD); - tup->fcr_shadow |= UART_FCR_DMA_SELECT; - tegra_uart_write(tup, tup->fcr_shadow, UART_FCR); - - ret = tegra_uart_start_rx_dma(tup); + ret = tegra_set_baudrate(tup, TEGRA_UART_DEFAULT_BAUD); if (ret < 0) { - dev_err(tup->uport.dev, "Not able to start Rx DMA\n"); + clk_disable_unprepare(tup->uart_clk); + dev_err(tup->uport.dev, "Failed to set baud rate\n"); return ret; } + if (!tup->use_rx_pio) { + tup->lcr_shadow = TEGRA_UART_DEFAULT_LSR; + tup->fcr_shadow |= UART_FCR_DMA_SELECT; + tegra_uart_write(tup, tup->fcr_shadow, UART_FCR); + } else { + tegra_uart_write(tup, tup->fcr_shadow, UART_FCR); + } tup->rx_in_progress = 1; /* - * Enable IE_RXS for the receive status interrupts like line errros. + * Enable IE_RXS for the receive status interrupts like line errors. * Enable IE_RX_TIMEOUT to get the bytes which cannot be DMA'd. * - * If using DMA mode, enable EORD instead of receive interrupt which - * will interrupt after the UART is done with the receive instead of - * the interrupt when the FIFO "threshold" is reached. - * * EORD is different interrupt than RX_TIMEOUT - RX_TIMEOUT occurs when * the DATA is sitting in the FIFO and couldn't be transferred to the - * DMA as the DMA size alignment(4 bytes) is not met. EORD will be + * DMA as the DMA size alignment (4 bytes) is not met. EORD will be * triggered when there is a pause of the incomming data stream for 4 * characters long. * @@ -889,11 +1103,41 @@ static int tegra_uart_hw_init(struct tegra_uart_port *tup) * both the EORD as well as RX_TIMEOUT - SW sees RX_TIMEOUT first * then the EORD. */ - tup->ier_shadow = UART_IER_RLSI | UART_IER_RTOIE | TEGRA_UART_IER_EORD; + tup->ier_shadow = UART_IER_RLSI | UART_IER_RTOIE | UART_IER_RDI; + + /* + * If using DMA mode, enable EORD interrupt to notify about RX + * completion. + */ + if (!tup->use_rx_pio) + tup->ier_shadow |= TEGRA_UART_IER_EORD; + tegra_uart_write(tup, tup->ier_shadow, UART_IER); return 0; } +static void tegra_uart_dma_channel_free(struct tegra_uart_port *tup, + bool dma_to_memory) +{ + if (dma_to_memory) { + dmaengine_terminate_all(tup->rx_dma_chan); + dma_release_channel(tup->rx_dma_chan); + dma_free_coherent(tup->uport.dev, TEGRA_UART_RX_DMA_BUFFER_SIZE, + tup->rx_dma_buf_virt, tup->rx_dma_buf_phys); + tup->rx_dma_chan = NULL; + tup->rx_dma_buf_phys = 0; + tup->rx_dma_buf_virt = NULL; + } else { + dmaengine_terminate_all(tup->tx_dma_chan); + dma_release_channel(tup->tx_dma_chan); + dma_unmap_single(tup->uport.dev, tup->tx_dma_buf_phys, + UART_XMIT_SIZE, DMA_TO_DEVICE); + tup->tx_dma_chan = NULL; + tup->tx_dma_buf_phys = 0; + tup->tx_dma_buf_virt = NULL; + } +} + static int tegra_uart_dma_channel_allocate(struct tegra_uart_port *tup, bool dma_to_memory) { @@ -902,15 +1146,13 @@ static int tegra_uart_dma_channel_allocate(struct tegra_uart_port *tup, dma_addr_t dma_phys; int ret; struct dma_slave_config dma_sconfig; - dma_cap_mask_t mask; - dma_cap_zero(mask); - dma_cap_set(DMA_SLAVE, mask); - dma_chan = dma_request_channel(mask, NULL, NULL); - if (!dma_chan) { + dma_chan = dma_request_chan(tup->uport.dev, dma_to_memory ? "rx" : "tx"); + if (IS_ERR(dma_chan)) { + ret = PTR_ERR(dma_chan); dev_err(tup->uport.dev, - "Dma channel is not available, will try later\n"); - return -EPROBE_DEFER; + "DMA channel alloc failed: %d\n", ret); + return ret; } if (dma_to_memory) { @@ -923,68 +1165,41 @@ static int tegra_uart_dma_channel_allocate(struct tegra_uart_port *tup, dma_release_channel(dma_chan); return -ENOMEM; } - } else { - dma_phys = dma_map_single(tup->uport.dev, - tup->uport.state->xmit.buf, UART_XMIT_SIZE, - DMA_TO_DEVICE); - dma_buf = tup->uport.state->xmit.buf; - } - - dma_sconfig.slave_id = tup->dma_req_sel; - if (dma_to_memory) { + dma_sync_single_for_device(tup->uport.dev, dma_phys, + TEGRA_UART_RX_DMA_BUFFER_SIZE, + DMA_TO_DEVICE); dma_sconfig.src_addr = tup->uport.mapbase; dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; - dma_sconfig.src_maxburst = 4; + dma_sconfig.src_maxburst = tup->cdata->max_dma_burst_bytes; + tup->rx_dma_chan = dma_chan; + tup->rx_dma_buf_virt = dma_buf; + tup->rx_dma_buf_phys = dma_phys; } else { + dma_buf = tup->uport.state->port.xmit_buf; + dma_phys = dma_map_single(tup->uport.dev, + dma_buf, UART_XMIT_SIZE, DMA_TO_DEVICE); + if (dma_mapping_error(tup->uport.dev, dma_phys)) { + dev_err(tup->uport.dev, "dma_map_single tx failed\n"); + dma_release_channel(dma_chan); + return -ENOMEM; + } dma_sconfig.dst_addr = tup->uport.mapbase; dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; dma_sconfig.dst_maxburst = 16; + tup->tx_dma_chan = dma_chan; + tup->tx_dma_buf_virt = dma_buf; + tup->tx_dma_buf_phys = dma_phys; } ret = dmaengine_slave_config(dma_chan, &dma_sconfig); if (ret < 0) { dev_err(tup->uport.dev, "Dma slave config failed, err = %d\n", ret); - goto scrub; + tegra_uart_dma_channel_free(tup, dma_to_memory); + return ret; } - if (dma_to_memory) { - tup->rx_dma_chan = dma_chan; - tup->rx_dma_buf_virt = dma_buf; - tup->rx_dma_buf_phys = dma_phys; - } else { - tup->tx_dma_chan = dma_chan; - tup->tx_dma_buf_virt = dma_buf; - tup->tx_dma_buf_phys = dma_phys; - } return 0; - -scrub: - dma_release_channel(dma_chan); - return ret; -} - -static void tegra_uart_dma_channel_free(struct tegra_uart_port *tup, - bool dma_to_memory) -{ - struct dma_chan *dma_chan; - - if (dma_to_memory) { - dma_free_coherent(tup->uport.dev, TEGRA_UART_RX_DMA_BUFFER_SIZE, - tup->rx_dma_buf_virt, tup->rx_dma_buf_phys); - dma_chan = tup->rx_dma_chan; - tup->rx_dma_chan = NULL; - tup->rx_dma_buf_phys = 0; - tup->rx_dma_buf_virt = NULL; - } else { - dma_unmap_single(tup->uport.dev, tup->tx_dma_buf_phys, - UART_XMIT_SIZE, DMA_TO_DEVICE); - dma_chan = tup->tx_dma_chan; - tup->tx_dma_chan = NULL; - tup->tx_dma_buf_phys = 0; - tup->tx_dma_buf_virt = NULL; - } - dma_release_channel(dma_chan); } static int tegra_uart_startup(struct uart_port *u) @@ -992,16 +1207,22 @@ static int tegra_uart_startup(struct uart_port *u) struct tegra_uart_port *tup = to_tegra_uport(u); int ret; - ret = tegra_uart_dma_channel_allocate(tup, false); - if (ret < 0) { - dev_err(u->dev, "Tx Dma allocation failed, err = %d\n", ret); - return ret; + if (!tup->use_tx_pio) { + ret = tegra_uart_dma_channel_allocate(tup, false); + if (ret < 0) { + dev_err(u->dev, "Tx Dma allocation failed, err = %d\n", + ret); + return ret; + } } - ret = tegra_uart_dma_channel_allocate(tup, true); - if (ret < 0) { - dev_err(u->dev, "Rx Dma allocation failed, err = %d\n", ret); - goto fail_rx_dma; + if (!tup->use_rx_pio) { + ret = tegra_uart_dma_channel_allocate(tup, true); + if (ret < 0) { + dev_err(u->dev, "Rx Dma allocation failed, err = %d\n", + ret); + goto fail_rx_dma; + } } ret = tegra_uart_hw_init(tup); @@ -1010,32 +1231,44 @@ static int tegra_uart_startup(struct uart_port *u) goto fail_hw_init; } - ret = request_irq(u->irq, tegra_uart_isr, IRQF_DISABLED, + ret = request_irq(u->irq, tegra_uart_isr, 0, dev_name(u->dev), tup); if (ret < 0) { dev_err(u->dev, "Failed to register ISR for IRQ %d\n", u->irq); - goto fail_hw_init; + goto fail_request_irq; } return 0; +fail_request_irq: + /* tup->uart_clk is already enabled in tegra_uart_hw_init */ + clk_disable_unprepare(tup->uart_clk); fail_hw_init: - tegra_uart_dma_channel_free(tup, true); + if (!tup->use_rx_pio) + tegra_uart_dma_channel_free(tup, true); fail_rx_dma: - tegra_uart_dma_channel_free(tup, false); + if (!tup->use_tx_pio) + tegra_uart_dma_channel_free(tup, false); return ret; } -static void tegra_uart_shutdown(struct uart_port *u) +/* + * Flush any TX data submitted for DMA and PIO. Called when the + * TX circular buffer is reset. + */ +static void tegra_uart_flush_buffer(struct uart_port *u) { struct tegra_uart_port *tup = to_tegra_uport(u); - tegra_uart_hw_deinit(tup); + tup->tx_bytes = 0; + if (tup->tx_dma_chan) + dmaengine_terminate_all(tup->tx_dma_chan); +} - tup->rx_in_progress = 0; - tup->tx_in_progress = 0; +static void tegra_uart_shutdown(struct uart_port *u) +{ + struct tegra_uart_port *tup = to_tegra_uport(u); - tegra_uart_dma_channel_free(tup, true); - tegra_uart_dma_channel_free(tup, false); + tegra_uart_hw_deinit(tup); free_irq(u->irq, tup); } @@ -1050,25 +1283,27 @@ static void tegra_uart_enable_ms(struct uart_port *u) } static void tegra_uart_set_termios(struct uart_port *u, - struct ktermios *termios, struct ktermios *oldtermios) + struct ktermios *termios, + const struct ktermios *oldtermios) { struct tegra_uart_port *tup = to_tegra_uport(u); unsigned int baud; unsigned long flags; unsigned int lcr; - int symb_bit = 1; + unsigned char char_bits; struct clk *parent_clk = clk_get_parent(tup->uart_clk); unsigned long parent_clk_rate = clk_get_rate(parent_clk); int max_divider = (tup->cdata->support_clk_src_div) ? 0x7FFF : 0xFFFF; + int ret; max_divider *= 16; - spin_lock_irqsave(&u->lock, flags); + uart_port_lock_irqsave(u, &flags); /* Changing configuration, it is safe to stop any rx now */ if (tup->rts_active) set_rts(tup, false); - /* Clear all interrupts as configuration is going to be change */ + /* Clear all interrupts as configuration is going to be changed */ tegra_uart_write(tup, tup->ier_shadow | UART_IER_RDI, UART_IER); tegra_uart_read(tup, UART_IER); tegra_uart_write(tup, 0, UART_IER); @@ -1082,7 +1317,6 @@ static void tegra_uart_set_termios(struct uart_port *u, termios->c_cflag &= ~CMSPAR; if ((termios->c_cflag & PARENB) == PARENB) { - symb_bit++; if (termios->c_cflag & PARODD) { lcr |= UART_LCR_PARITY; lcr &= ~UART_LCR_EPAR; @@ -1094,48 +1328,33 @@ static void tegra_uart_set_termios(struct uart_port *u, } } + char_bits = tty_get_char_size(termios->c_cflag); lcr &= ~UART_LCR_WLEN8; - switch (termios->c_cflag & CSIZE) { - case CS5: - lcr |= UART_LCR_WLEN5; - symb_bit += 5; - break; - case CS6: - lcr |= UART_LCR_WLEN6; - symb_bit += 6; - break; - case CS7: - lcr |= UART_LCR_WLEN7; - symb_bit += 7; - break; - default: - lcr |= UART_LCR_WLEN8; - symb_bit += 8; - break; - } + lcr |= UART_LCR_WLEN(char_bits); /* Stop bits */ - if (termios->c_cflag & CSTOPB) { + if (termios->c_cflag & CSTOPB) lcr |= UART_LCR_STOP; - symb_bit += 2; - } else { + else lcr &= ~UART_LCR_STOP; - symb_bit++; - } tegra_uart_write(tup, lcr, UART_LCR); tup->lcr_shadow = lcr; - tup->symb_bit = symb_bit; + tup->symb_bit = tty_get_frame_size(termios->c_cflag); /* Baud rate. */ baud = uart_get_baud_rate(u, termios, oldtermios, parent_clk_rate/max_divider, parent_clk_rate/16); - spin_unlock_irqrestore(&u->lock, flags); - tegra_set_baudrate(tup, baud); + uart_port_unlock_irqrestore(u, flags); + ret = tegra_set_baudrate(tup, baud); + if (ret < 0) { + dev_err(tup->uport.dev, "Failed to set baud rate\n"); + return; + } if (tty_termios_baud_rate(termios)) tty_termios_encode_baud_rate(termios, baud, baud); - spin_lock_irqsave(&u->lock, flags); + uart_port_lock_irqsave(u, &flags); /* Flow control */ if (termios->c_cflag & CRTSCTS) { @@ -1154,29 +1373,21 @@ static void tegra_uart_set_termios(struct uart_port *u, /* update the port timeout based on new settings */ uart_update_timeout(u, termios->c_cflag, baud); - /* Make sure all write has completed */ + /* Make sure all writes have completed */ tegra_uart_read(tup, UART_IER); - /* Reenable interrupt */ + /* Re-enable interrupt */ tegra_uart_write(tup, tup->ier_shadow, UART_IER); tegra_uart_read(tup, UART_IER); - spin_unlock_irqrestore(&u->lock, flags); - return; -} - -/* - * Flush any TX data submitted for DMA and PIO. Called when the - * TX circular buffer is reset. - */ -static void tegra_uart_flush_buffer(struct uart_port *u) -{ - struct tegra_uart_port *tup = to_tegra_uport(u); + tup->uport.ignore_status_mask = 0; + /* Ignore all characters if CREAD is not set */ + if ((termios->c_cflag & CREAD) == 0) + tup->uport.ignore_status_mask |= UART_LSR_DR; + if (termios->c_iflag & IGNBRK) + tup->uport.ignore_status_mask |= UART_LSR_BI; - tup->tx_bytes = 0; - if (tup->tx_dma_chan) - dmaengine_terminate_all(tup->tx_dma_chan); - return; + uart_port_unlock_irqrestore(u, flags); } static const char *tegra_uart_type(struct uart_port *u) @@ -1184,7 +1395,7 @@ static const char *tegra_uart_type(struct uart_port *u) return TEGRA_UART_TYPE; } -static struct uart_ops tegra_uart_ops = { +static const struct uart_ops tegra_uart_ops = { .tx_empty = tegra_uart_tx_empty, .set_mctrl = tegra_uart_set_mctrl, .get_mctrl = tegra_uart_get_mctrl, @@ -1206,7 +1417,7 @@ static struct uart_driver tegra_uart_driver = { .owner = THIS_MODULE, .driver_name = "tegra_hsuart", .dev_name = "ttyTHS", - .cons = 0, + .cons = NULL, .nr = TEGRA_UART_MAXIMUM, }; @@ -1214,16 +1425,12 @@ static int tegra_uart_parse_dt(struct platform_device *pdev, struct tegra_uart_port *tup) { struct device_node *np = pdev->dev.of_node; - u32 of_dma[2]; int port; - - if (of_property_read_u32_array(np, "nvidia,dma-request-selector", - of_dma, 2) >= 0) { - tup->dma_req_sel = of_dma[1]; - } else { - dev_err(&pdev->dev, "missing dma requestor in device tree\n"); - return -EINVAL; - } + int ret; + int index; + u32 pval; + int count; + int n_entries; port = of_alias_get_id(np, "serial"); if (port < 0) { @@ -1234,22 +1441,102 @@ static int tegra_uart_parse_dt(struct platform_device *pdev, tup->enable_modem_interrupt = of_property_read_bool(np, "nvidia,enable-modem-interrupt"); + + index = of_property_match_string(np, "dma-names", "rx"); + if (index < 0) { + tup->use_rx_pio = true; + dev_info(&pdev->dev, "RX in PIO mode\n"); + } + index = of_property_match_string(np, "dma-names", "tx"); + if (index < 0) { + tup->use_tx_pio = true; + dev_info(&pdev->dev, "TX in PIO mode\n"); + } + + n_entries = of_property_count_u32_elems(np, "nvidia,adjust-baud-rates"); + if (n_entries > 0) { + tup->n_adjustable_baud_rates = n_entries / 3; + tup->baud_tolerance = + devm_kzalloc(&pdev->dev, (tup->n_adjustable_baud_rates) * + sizeof(*tup->baud_tolerance), GFP_KERNEL); + if (!tup->baud_tolerance) + return -ENOMEM; + for (count = 0, index = 0; count < n_entries; count += 3, + index++) { + ret = + of_property_read_u32_index(np, + "nvidia,adjust-baud-rates", + count, &pval); + if (!ret) + tup->baud_tolerance[index].lower_range_baud = + pval; + ret = + of_property_read_u32_index(np, + "nvidia,adjust-baud-rates", + count + 1, &pval); + if (!ret) + tup->baud_tolerance[index].upper_range_baud = + pval; + ret = + of_property_read_u32_index(np, + "nvidia,adjust-baud-rates", + count + 2, &pval); + if (!ret) + tup->baud_tolerance[index].tolerance = + (s32)pval; + } + } else { + tup->n_adjustable_baud_rates = 0; + } + return 0; } -struct tegra_uart_chip_data tegra20_uart_chip_data = { +static struct tegra_uart_chip_data tegra20_uart_chip_data = { .tx_fifo_full_status = false, .allow_txfifo_reset_fifo_mode = true, .support_clk_src_div = false, + .fifo_mode_enable_status = false, + .uart_max_port = 5, + .max_dma_burst_bytes = 4, + .error_tolerance_low_range = -4, + .error_tolerance_high_range = 4, +}; + +static struct tegra_uart_chip_data tegra30_uart_chip_data = { + .tx_fifo_full_status = true, + .allow_txfifo_reset_fifo_mode = false, + .support_clk_src_div = true, + .fifo_mode_enable_status = false, + .uart_max_port = 5, + .max_dma_burst_bytes = 4, + .error_tolerance_low_range = -4, + .error_tolerance_high_range = 4, +}; + +static struct tegra_uart_chip_data tegra186_uart_chip_data = { + .tx_fifo_full_status = true, + .allow_txfifo_reset_fifo_mode = false, + .support_clk_src_div = true, + .fifo_mode_enable_status = true, + .uart_max_port = 8, + .max_dma_burst_bytes = 8, + .error_tolerance_low_range = 0, + .error_tolerance_high_range = 4, }; -struct tegra_uart_chip_data tegra30_uart_chip_data = { +static struct tegra_uart_chip_data tegra194_uart_chip_data = { .tx_fifo_full_status = true, .allow_txfifo_reset_fifo_mode = false, .support_clk_src_div = true, + .fifo_mode_enable_status = true, + .uart_max_port = 8, + .max_dma_burst_bytes = 8, + .error_tolerance_low_range = -2, + .error_tolerance_high_range = 2, }; -static struct of_device_id tegra_uart_of_match[] = { +static const struct of_device_id tegra_uart_of_match[] = { { .compatible = "nvidia,tegra30-hsuart", .data = &tegra30_uart_chip_data, @@ -1257,6 +1544,12 @@ static struct of_device_id tegra_uart_of_match[] = { .compatible = "nvidia,tegra20-hsuart", .data = &tegra20_uart_chip_data, }, { + .compatible = "nvidia,tegra186-hsuart", + .data = &tegra186_uart_chip_data, + }, { + .compatible = "nvidia,tegra194-hsuart", + .data = &tegra194_uart_chip_data, + }, { }, }; MODULE_DEVICE_TABLE(of, tegra_uart_of_match); @@ -1268,14 +1561,12 @@ static int tegra_uart_probe(struct platform_device *pdev) struct resource *resource; int ret; const struct tegra_uart_chip_data *cdata; - const struct of_device_id *match; - match = of_match_device(tegra_uart_of_match, &pdev->dev); - if (!match) { + cdata = of_device_get_match_data(&pdev->dev); + if (!cdata) { dev_err(&pdev->dev, "Error: No device match found\n"); return -ENODEV; } - cdata = match->data; tup = devm_kzalloc(&pdev->dev, sizeof(*tup), GFP_KERNEL); if (!tup) { @@ -1295,25 +1586,27 @@ static int tegra_uart_probe(struct platform_device *pdev) tup->cdata = cdata; platform_set_drvdata(pdev, tup); - resource = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!resource) { - dev_err(&pdev->dev, "No IO memory resource\n"); - return -ENODEV; - } - u->mapbase = resource->start; - u->membase = devm_ioremap_resource(&pdev->dev, resource); + u->membase = devm_platform_get_and_ioremap_resource(pdev, 0, &resource); if (IS_ERR(u->membase)) return PTR_ERR(u->membase); + u->mapbase = resource->start; tup->uart_clk = devm_clk_get(&pdev->dev, NULL); - if (IS_ERR(tup->uart_clk)) { - dev_err(&pdev->dev, "Couldn't get the clock\n"); - return PTR_ERR(tup->uart_clk); + if (IS_ERR(tup->uart_clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(tup->uart_clk), "Couldn't get the clock"); + + tup->rst = devm_reset_control_get_exclusive(&pdev->dev, "serial"); + if (IS_ERR(tup->rst)) { + dev_err(&pdev->dev, "Couldn't get the reset\n"); + return PTR_ERR(tup->rst); } u->iotype = UPIO_MEM32; - u->irq = platform_get_irq(pdev, 0); + ret = platform_get_irq(pdev, 0); + if (ret < 0) + return ret; + u->irq = ret; u->regshift = 2; ret = uart_add_one_port(&tegra_uart_driver, u); if (ret < 0) { @@ -1323,13 +1616,12 @@ static int tegra_uart_probe(struct platform_device *pdev) return ret; } -static int tegra_uart_remove(struct platform_device *pdev) +static void tegra_uart_remove(struct platform_device *pdev) { struct tegra_uart_port *tup = platform_get_drvdata(pdev); struct uart_port *u = &tup->uport; uart_remove_one_port(&tegra_uart_driver, u); - return 0; } #ifdef CONFIG_PM_SLEEP @@ -1367,11 +1659,23 @@ static struct platform_driver tegra_uart_platform_driver = { static int __init tegra_uart_init(void) { int ret; + struct device_node *node; + const struct of_device_id *match = NULL; + const struct tegra_uart_chip_data *cdata = NULL; + + node = of_find_matching_node(NULL, tegra_uart_of_match); + if (node) + match = of_match_node(tegra_uart_of_match, node); + of_node_put(node); + if (match) + cdata = match->data; + if (cdata) + tegra_uart_driver.nr = cdata->uart_max_port; ret = uart_register_driver(&tegra_uart_driver); if (ret < 0) { pr_err("Could not register %s driver\n", - tegra_uart_driver.driver_name); + tegra_uart_driver.driver_name); return ret; } |