diff options
Diffstat (limited to 'drivers/tty/serial/qcom_geni_serial.c')
| -rw-r--r-- | drivers/tty/serial/qcom_geni_serial.c | 1158 |
1 files changed, 1158 insertions, 0 deletions
diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c new file mode 100644 index 000000000000..65ff669373d4 --- /dev/null +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -0,0 +1,1158 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2017-2018, The Linux foundation. All rights reserved. + +#include <linux/clk.h> +#include <linux/console.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/qcom-geni-se.h> +#include <linux/serial.h> +#include <linux/serial_core.h> +#include <linux/slab.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> + +/* UART specific GENI registers */ +#define SE_UART_TX_TRANS_CFG 0x25c +#define SE_UART_TX_WORD_LEN 0x268 +#define SE_UART_TX_STOP_BIT_LEN 0x26c +#define SE_UART_TX_TRANS_LEN 0x270 +#define SE_UART_RX_TRANS_CFG 0x280 +#define SE_UART_RX_WORD_LEN 0x28c +#define SE_UART_RX_STALE_CNT 0x294 +#define SE_UART_TX_PARITY_CFG 0x2a4 +#define SE_UART_RX_PARITY_CFG 0x2a8 + +/* SE_UART_TRANS_CFG */ +#define UART_TX_PAR_EN BIT(0) +#define UART_CTS_MASK BIT(1) + +/* SE_UART_TX_WORD_LEN */ +#define TX_WORD_LEN_MSK GENMASK(9, 0) + +/* SE_UART_TX_STOP_BIT_LEN */ +#define TX_STOP_BIT_LEN_MSK GENMASK(23, 0) +#define TX_STOP_BIT_LEN_1 0 +#define TX_STOP_BIT_LEN_1_5 1 +#define TX_STOP_BIT_LEN_2 2 + +/* SE_UART_TX_TRANS_LEN */ +#define TX_TRANS_LEN_MSK GENMASK(23, 0) + +/* SE_UART_RX_TRANS_CFG */ +#define UART_RX_INS_STATUS_BIT BIT(2) +#define UART_RX_PAR_EN BIT(3) + +/* SE_UART_RX_WORD_LEN */ +#define RX_WORD_LEN_MASK GENMASK(9, 0) + +/* SE_UART_RX_STALE_CNT */ +#define RX_STALE_CNT GENMASK(23, 0) + +/* SE_UART_TX_PARITY_CFG/RX_PARITY_CFG */ +#define PAR_CALC_EN BIT(0) +#define PAR_MODE_MSK GENMASK(2, 1) +#define PAR_MODE_SHFT 1 +#define PAR_EVEN 0x00 +#define PAR_ODD 0x01 +#define PAR_SPACE 0x10 +#define PAR_MARK 0x11 + +/* UART M_CMD OP codes */ +#define UART_START_TX 0x1 +#define UART_START_BREAK 0x4 +#define UART_STOP_BREAK 0x5 +/* UART S_CMD OP codes */ +#define UART_START_READ 0x1 +#define UART_PARAM 0x1 + +#define UART_OVERSAMPLING 32 +#define STALE_TIMEOUT 16 +#define DEFAULT_BITS_PER_CHAR 10 +#define GENI_UART_CONS_PORTS 1 +#define DEF_FIFO_DEPTH_WORDS 16 +#define DEF_TX_WM 2 +#define DEF_FIFO_WIDTH_BITS 32 +#define UART_CONSOLE_RX_WM 2 + +#ifdef CONFIG_CONSOLE_POLL +#define RX_BYTES_PW 1 +#else +#define RX_BYTES_PW 4 +#endif + +struct qcom_geni_serial_port { + struct uart_port uport; + struct geni_se se; + char name[20]; + u32 tx_fifo_depth; + u32 tx_fifo_width; + u32 rx_fifo_depth; + u32 tx_wm; + u32 rx_wm; + u32 rx_rfr; + enum geni_se_xfer_mode xfer_mode; + bool setup; + int (*handle_rx)(struct uart_port *uport, u32 bytes, bool drop); + unsigned int xmit_size; + unsigned int baud; + unsigned int tx_bytes_pw; + unsigned int rx_bytes_pw; + bool brk; +}; + +static const struct uart_ops qcom_geni_serial_pops; +static struct uart_driver qcom_geni_console_driver; +static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop); +static unsigned int qcom_geni_serial_tx_empty(struct uart_port *port); +static void qcom_geni_serial_stop_rx(struct uart_port *uport); + +static const unsigned long root_freq[] = {7372800, 14745600, 19200000, 29491200, + 32000000, 48000000, 64000000, 80000000, + 96000000, 100000000}; + +#define to_dev_port(ptr, member) \ + container_of(ptr, struct qcom_geni_serial_port, member) + +static struct qcom_geni_serial_port qcom_geni_console_port; + +static int qcom_geni_serial_request_port(struct uart_port *uport) +{ + struct platform_device *pdev = to_platform_device(uport->dev); + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + uport->membase = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(uport->membase)) + return PTR_ERR(uport->membase); + port->se.base = uport->membase; + return 0; +} + +static void qcom_geni_serial_config_port(struct uart_port *uport, int cfg_flags) +{ + if (cfg_flags & UART_CONFIG_TYPE) { + uport->type = PORT_MSM; + qcom_geni_serial_request_port(uport); + } +} + +static unsigned int qcom_geni_cons_get_mctrl(struct uart_port *uport) +{ + return TIOCM_DSR | TIOCM_CAR | TIOCM_CTS; +} + +static void qcom_geni_cons_set_mctrl(struct uart_port *uport, + unsigned int mctrl) +{ +} + +static const char *qcom_geni_serial_get_type(struct uart_port *uport) +{ + return "MSM"; +} + +static struct qcom_geni_serial_port *get_port_from_line(int line) +{ + if (line < 0 || line >= GENI_UART_CONS_PORTS) + return ERR_PTR(-ENXIO); + return &qcom_geni_console_port; +} + +static bool qcom_geni_serial_poll_bit(struct uart_port *uport, + int offset, int field, bool set) +{ + u32 reg; + struct qcom_geni_serial_port *port; + unsigned int baud; + unsigned int fifo_bits; + unsigned long timeout_us = 20000; + + /* Ensure polling is not re-ordered before the prior writes/reads */ + mb(); + + if (uport->private_data) { + port = to_dev_port(uport, uport); + baud = port->baud; + if (!baud) + baud = 115200; + fifo_bits = port->tx_fifo_depth * port->tx_fifo_width; + /* + * Total polling iterations based on FIFO worth of bytes to be + * sent at current baud. Add a little fluff to the wait. + */ + timeout_us = ((fifo_bits * USEC_PER_SEC) / baud) + 500; + } + + return !readl_poll_timeout_atomic(uport->membase + offset, reg, + (bool)(reg & field) == set, 10, timeout_us); +} + +static void qcom_geni_serial_setup_tx(struct uart_port *uport, u32 xmit_size) +{ + u32 m_cmd; + + writel_relaxed(xmit_size, uport->membase + SE_UART_TX_TRANS_LEN); + m_cmd = UART_START_TX << M_OPCODE_SHFT; + writel(m_cmd, uport->membase + SE_GENI_M_CMD0); +} + +static void qcom_geni_serial_poll_tx_done(struct uart_port *uport) +{ + int done; + u32 irq_clear = M_CMD_DONE_EN; + + done = qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS, + M_CMD_DONE_EN, true); + if (!done) { + writel_relaxed(M_GENI_CMD_ABORT, uport->membase + + SE_GENI_M_CMD_CTRL_REG); + irq_clear |= M_CMD_ABORT_EN; + qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS, + M_CMD_ABORT_EN, true); + } + writel_relaxed(irq_clear, uport->membase + SE_GENI_M_IRQ_CLEAR); +} + +static void qcom_geni_serial_abort_rx(struct uart_port *uport) +{ + u32 irq_clear = S_CMD_DONE_EN | S_CMD_ABORT_EN; + + writel(S_GENI_CMD_ABORT, uport->membase + SE_GENI_S_CMD_CTRL_REG); + qcom_geni_serial_poll_bit(uport, SE_GENI_S_CMD_CTRL_REG, + S_GENI_CMD_ABORT, false); + writel_relaxed(irq_clear, uport->membase + SE_GENI_S_IRQ_CLEAR); + writel_relaxed(FORCE_DEFAULT, uport->membase + GENI_FORCE_DEFAULT_REG); +} + +#ifdef CONFIG_CONSOLE_POLL +static int qcom_geni_serial_get_char(struct uart_port *uport) +{ + u32 rx_fifo; + u32 status; + + status = readl_relaxed(uport->membase + SE_GENI_M_IRQ_STATUS); + writel_relaxed(status, uport->membase + SE_GENI_M_IRQ_CLEAR); + + status = readl_relaxed(uport->membase + SE_GENI_S_IRQ_STATUS); + writel_relaxed(status, uport->membase + SE_GENI_S_IRQ_CLEAR); + + /* + * Ensure the writes to clear interrupts is not re-ordered after + * reading the data. + */ + mb(); + + status = readl_relaxed(uport->membase + SE_GENI_RX_FIFO_STATUS); + if (!(status & RX_FIFO_WC_MSK)) + return NO_POLL_CHAR; + + rx_fifo = readl(uport->membase + SE_GENI_RX_FIFOn); + return rx_fifo & 0xff; +} + +static void qcom_geni_serial_poll_put_char(struct uart_port *uport, + unsigned char c) +{ + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + + writel_relaxed(port->tx_wm, uport->membase + SE_GENI_TX_WATERMARK_REG); + qcom_geni_serial_setup_tx(uport, 1); + WARN_ON(!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS, + M_TX_FIFO_WATERMARK_EN, true)); + writel_relaxed(c, uport->membase + SE_GENI_TX_FIFOn); + writel_relaxed(M_TX_FIFO_WATERMARK_EN, uport->membase + + SE_GENI_M_IRQ_CLEAR); + qcom_geni_serial_poll_tx_done(uport); +} +#endif + +#ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE +static void qcom_geni_serial_wr_char(struct uart_port *uport, int ch) +{ + writel_relaxed(ch, uport->membase + SE_GENI_TX_FIFOn); +} + +static void +__qcom_geni_serial_console_write(struct uart_port *uport, const char *s, + unsigned int count) +{ + int i; + u32 bytes_to_send = count; + + for (i = 0; i < count; i++) { + if (s[i] == '\n') + bytes_to_send++; + } + + writel_relaxed(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG); + qcom_geni_serial_setup_tx(uport, bytes_to_send); + for (i = 0; i < count; ) { + size_t chars_to_write = 0; + size_t avail = DEF_FIFO_DEPTH_WORDS - DEF_TX_WM; + + /* + * If the WM bit never set, then the Tx state machine is not + * in a valid state, so break, cancel/abort any existing + * command. Unfortunately the current data being written is + * lost. + */ + if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS, + M_TX_FIFO_WATERMARK_EN, true)) + break; + chars_to_write = min_t(size_t, (size_t)(count - i), avail / 2); + uart_console_write(uport, s + i, chars_to_write, + qcom_geni_serial_wr_char); + writel_relaxed(M_TX_FIFO_WATERMARK_EN, uport->membase + + SE_GENI_M_IRQ_CLEAR); + i += chars_to_write; + } + qcom_geni_serial_poll_tx_done(uport); +} + +static void qcom_geni_serial_console_write(struct console *co, const char *s, + unsigned int count) +{ + struct uart_port *uport; + struct qcom_geni_serial_port *port; + bool locked = true; + unsigned long flags; + + WARN_ON(co->index < 0 || co->index >= GENI_UART_CONS_PORTS); + + port = get_port_from_line(co->index); + if (IS_ERR(port)) + return; + + uport = &port->uport; + if (oops_in_progress) + locked = spin_trylock_irqsave(&uport->lock, flags); + else + spin_lock_irqsave(&uport->lock, flags); + + /* Cancel the current write to log the fault */ + if (!locked) { + geni_se_cancel_m_cmd(&port->se); + if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS, + M_CMD_CANCEL_EN, true)) { + geni_se_abort_m_cmd(&port->se); + qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS, + M_CMD_ABORT_EN, true); + writel_relaxed(M_CMD_ABORT_EN, uport->membase + + SE_GENI_M_IRQ_CLEAR); + } + writel_relaxed(M_CMD_CANCEL_EN, uport->membase + + SE_GENI_M_IRQ_CLEAR); + } + + __qcom_geni_serial_console_write(uport, s, count); + if (locked) + spin_unlock_irqrestore(&uport->lock, flags); +} + +static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop) +{ + u32 i; + unsigned char buf[sizeof(u32)]; + struct tty_port *tport; + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + + tport = &uport->state->port; + for (i = 0; i < bytes; ) { + int c; + int chunk = min_t(int, bytes - i, port->rx_bytes_pw); + + ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, buf, 1); + i += chunk; + if (drop) + continue; + + for (c = 0; c < chunk; c++) { + int sysrq; + + uport->icount.rx++; + if (port->brk && buf[c] == 0) { + port->brk = false; + if (uart_handle_break(uport)) + continue; + } + + sysrq = uart_handle_sysrq_char(uport, buf[c]); + if (!sysrq) + tty_insert_flip_char(tport, buf[c], TTY_NORMAL); + } + } + if (!drop) + tty_flip_buffer_push(tport); + return 0; +} +#else +static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop) +{ + return -EPERM; +} + +#endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */ + +static void qcom_geni_serial_start_tx(struct uart_port *uport) +{ + u32 irq_en; + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + u32 status; + + if (port->xfer_mode == GENI_SE_FIFO) { + status = readl_relaxed(uport->membase + SE_GENI_STATUS); + if (status & M_GENI_CMD_ACTIVE) + return; + + if (!qcom_geni_serial_tx_empty(uport)) + return; + + /* + * Ensure writing to IRQ_EN & watermark registers are not + * re-ordered before checking the status of the Serial + * Engine and TX FIFO + */ + mb(); + + irq_en = readl_relaxed(uport->membase + SE_GENI_M_IRQ_EN); + irq_en |= M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN; + + writel_relaxed(port->tx_wm, uport->membase + + SE_GENI_TX_WATERMARK_REG); + writel_relaxed(irq_en, uport->membase + SE_GENI_M_IRQ_EN); + } +} + +static void qcom_geni_serial_stop_tx(struct uart_port *uport) +{ + u32 irq_en; + u32 status; + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + + irq_en = readl_relaxed(uport->membase + SE_GENI_M_IRQ_EN); + irq_en &= ~M_CMD_DONE_EN; + if (port->xfer_mode == GENI_SE_FIFO) { + irq_en &= ~M_TX_FIFO_WATERMARK_EN; + writel_relaxed(0, uport->membase + + SE_GENI_TX_WATERMARK_REG); + } + port->xmit_size = 0; + writel_relaxed(irq_en, uport->membase + SE_GENI_M_IRQ_EN); + status = readl_relaxed(uport->membase + SE_GENI_STATUS); + /* Possible stop tx is called multiple times. */ + if (!(status & M_GENI_CMD_ACTIVE)) + return; + + /* + * Ensure cancel command write is not re-ordered before checking + * the status of the Primary Sequencer. + */ + mb(); + + geni_se_cancel_m_cmd(&port->se); + if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS, + M_CMD_CANCEL_EN, true)) { + geni_se_abort_m_cmd(&port->se); + qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS, + M_CMD_ABORT_EN, true); + writel_relaxed(M_CMD_ABORT_EN, uport->membase + + SE_GENI_M_IRQ_CLEAR); + } + writel_relaxed(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR); +} + +static void qcom_geni_serial_start_rx(struct uart_port *uport) +{ + u32 irq_en; + u32 status; + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + + status = readl_relaxed(uport->membase + SE_GENI_STATUS); + if (status & S_GENI_CMD_ACTIVE) + qcom_geni_serial_stop_rx(uport); + + /* + * Ensure setup command write is not re-ordered before checking + * the status of the Secondary Sequencer. + */ + mb(); + + geni_se_setup_s_cmd(&port->se, UART_START_READ, 0); + + if (port->xfer_mode == GENI_SE_FIFO) { + irq_en = readl_relaxed(uport->membase + SE_GENI_S_IRQ_EN); + irq_en |= S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN; + writel_relaxed(irq_en, uport->membase + SE_GENI_S_IRQ_EN); + + irq_en = readl_relaxed(uport->membase + SE_GENI_M_IRQ_EN); + irq_en |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN; + writel_relaxed(irq_en, uport->membase + SE_GENI_M_IRQ_EN); + } +} + +static void qcom_geni_serial_stop_rx(struct uart_port *uport) +{ + u32 irq_en; + u32 status; + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + u32 irq_clear = S_CMD_DONE_EN; + + if (port->xfer_mode == GENI_SE_FIFO) { + irq_en = readl_relaxed(uport->membase + SE_GENI_S_IRQ_EN); + irq_en &= ~(S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN); + writel_relaxed(irq_en, uport->membase + SE_GENI_S_IRQ_EN); + + irq_en = readl_relaxed(uport->membase + SE_GENI_M_IRQ_EN); + irq_en &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN); + writel_relaxed(irq_en, uport->membase + SE_GENI_M_IRQ_EN); + } + + status = readl_relaxed(uport->membase + SE_GENI_STATUS); + /* Possible stop rx is called multiple times. */ + if (!(status & S_GENI_CMD_ACTIVE)) + return; + + /* + * Ensure cancel command write is not re-ordered before checking + * the status of the Secondary Sequencer. + */ + mb(); + + geni_se_cancel_s_cmd(&port->se); + qcom_geni_serial_poll_bit(uport, SE_GENI_S_CMD_CTRL_REG, + S_GENI_CMD_CANCEL, false); + status = readl_relaxed(uport->membase + SE_GENI_STATUS); + writel_relaxed(irq_clear, uport->membase + SE_GENI_S_IRQ_CLEAR); + if (status & S_GENI_CMD_ACTIVE) + qcom_geni_serial_abort_rx(uport); +} + +static void qcom_geni_serial_handle_rx(struct uart_port *uport, bool drop) +{ + u32 status; + u32 word_cnt; + u32 last_word_byte_cnt; + u32 last_word_partial; + u32 total_bytes; + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + + status = readl_relaxed(uport->membase + SE_GENI_RX_FIFO_STATUS); + word_cnt = status & RX_FIFO_WC_MSK; + last_word_partial = status & RX_LAST; + last_word_byte_cnt = (status & RX_LAST_BYTE_VALID_MSK) >> + RX_LAST_BYTE_VALID_SHFT; + + if (!word_cnt) + return; + total_bytes = port->rx_bytes_pw * (word_cnt - 1); + if (last_word_partial && last_word_byte_cnt) + total_bytes += last_word_byte_cnt; + else + total_bytes += port->rx_bytes_pw; + port->handle_rx(uport, total_bytes, drop); +} + +static void qcom_geni_serial_handle_tx(struct uart_port *uport) +{ + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + struct circ_buf *xmit = &uport->state->xmit; + size_t avail; + size_t remaining; + int i; + u32 status; + unsigned int chunk; + int tail; + + chunk = uart_circ_chars_pending(xmit); + status = readl_relaxed(uport->membase + SE_GENI_TX_FIFO_STATUS); + /* Both FIFO and framework buffer are drained */ + if (chunk == port->xmit_size && !status) { + port->xmit_size = 0; + uart_circ_clear(xmit); + qcom_geni_serial_stop_tx(uport); + goto out_write_wakeup; + } + chunk -= port->xmit_size; + + avail = (port->tx_fifo_depth - port->tx_wm) * port->tx_bytes_pw; + tail = (xmit->tail + port->xmit_size) & (UART_XMIT_SIZE - 1); + if (chunk > (UART_XMIT_SIZE - tail)) + chunk = UART_XMIT_SIZE - tail; + if (chunk > avail) + chunk = avail; + + if (!chunk) + goto out_write_wakeup; + + qcom_geni_serial_setup_tx(uport, chunk); + + remaining = chunk; + for (i = 0; i < chunk; ) { + unsigned int tx_bytes; + unsigned int buf = 0; + int c; + + tx_bytes = min_t(size_t, remaining, (size_t)port->tx_bytes_pw); + for (c = 0; c < tx_bytes ; c++) + buf |= (xmit->buf[tail + c] << (c * BITS_PER_BYTE)); + + writel_relaxed(buf, uport->membase + SE_GENI_TX_FIFOn); + + i += tx_bytes; + tail = (tail + tx_bytes) & (UART_XMIT_SIZE - 1); + uport->icount.tx += tx_bytes; + remaining -= tx_bytes; + } + qcom_geni_serial_poll_tx_done(uport); + port->xmit_size += chunk; +out_write_wakeup: + uart_write_wakeup(uport); +} + +static irqreturn_t qcom_geni_serial_isr(int isr, void *dev) +{ + unsigned int m_irq_status; + unsigned int s_irq_status; + struct uart_port *uport = dev; + unsigned long flags; + unsigned int m_irq_en; + bool drop_rx = false; + struct tty_port *tport = &uport->state->port; + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + + if (uport->suspended) + return IRQ_HANDLED; + + spin_lock_irqsave(&uport->lock, flags); + m_irq_status = readl_relaxed(uport->membase + SE_GENI_M_IRQ_STATUS); + s_irq_status = readl_relaxed(uport->membase + SE_GENI_S_IRQ_STATUS); + m_irq_en = readl_relaxed(uport->membase + SE_GENI_M_IRQ_EN); + writel_relaxed(m_irq_status, uport->membase + SE_GENI_M_IRQ_CLEAR); + writel_relaxed(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR); + + if (WARN_ON(m_irq_status & M_ILLEGAL_CMD_EN)) + goto out_unlock; + + if (s_irq_status & S_RX_FIFO_WR_ERR_EN) { + uport->icount.overrun++; + tty_insert_flip_char(tport, 0, TTY_OVERRUN); + } + + if (m_irq_status & (M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN) && + m_irq_en & (M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN)) + qcom_geni_serial_handle_tx(uport); + + if (s_irq_status & S_GP_IRQ_0_EN || s_irq_status & S_GP_IRQ_1_EN) { + if (s_irq_status & S_GP_IRQ_0_EN) + uport->icount.parity++; + drop_rx = true; + } else if (s_irq_status & S_GP_IRQ_2_EN || + s_irq_status & S_GP_IRQ_3_EN) { + uport->icount.brk++; + port->brk = true; + } + + if (s_irq_status & S_RX_FIFO_WATERMARK_EN || + s_irq_status & S_RX_FIFO_LAST_EN) + qcom_geni_serial_handle_rx(uport, drop_rx); + +out_unlock: + spin_unlock_irqrestore(&uport->lock, flags); + return IRQ_HANDLED; +} + +static int get_tx_fifo_size(struct qcom_geni_serial_port *port) +{ + struct uart_port *uport; + + if (!port) + return -ENODEV; + + uport = &port->uport; + port->tx_fifo_depth = geni_se_get_tx_fifo_depth(&port->se); + port->tx_fifo_width = geni_se_get_tx_fifo_width(&port->se); + port->rx_fifo_depth = geni_se_get_rx_fifo_depth(&port->se); + uport->fifosize = + (port->tx_fifo_depth * port->tx_fifo_width) / BITS_PER_BYTE; + return 0; +} + +static void set_rfr_wm(struct qcom_geni_serial_port *port) +{ + /* + * Set RFR (Flow off) to FIFO_DEPTH - 2. + * RX WM level at 10% RX_FIFO_DEPTH. + * TX WM level at 10% TX_FIFO_DEPTH. + */ + port->rx_rfr = port->rx_fifo_depth - 2; + port->rx_wm = UART_CONSOLE_RX_WM; + port->tx_wm = DEF_TX_WM; +} + +static void qcom_geni_serial_shutdown(struct uart_port *uport) +{ + unsigned long flags; + + /* Stop the console before stopping the current tx */ + console_stop(uport->cons); + + disable_irq(uport->irq); + free_irq(uport->irq, uport); + spin_lock_irqsave(&uport->lock, flags); + qcom_geni_serial_stop_tx(uport); + qcom_geni_serial_stop_rx(uport); + spin_unlock_irqrestore(&uport->lock, flags); +} + +static int qcom_geni_serial_port_setup(struct uart_port *uport) +{ + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + unsigned int rxstale = DEFAULT_BITS_PER_CHAR * STALE_TIMEOUT; + + set_rfr_wm(port); + writel_relaxed(rxstale, uport->membase + SE_UART_RX_STALE_CNT); + /* + * Make an unconditional cancel on the main sequencer to reset + * it else we could end up in data loss scenarios. + */ + port->xfer_mode = GENI_SE_FIFO; + qcom_geni_serial_poll_tx_done(uport); + geni_se_config_packing(&port->se, BITS_PER_BYTE, port->tx_bytes_pw, + false, true, false); + geni_se_config_packing(&port->se, BITS_PER_BYTE, port->rx_bytes_pw, + false, false, true); + geni_se_init(&port->se, port->rx_wm, port->rx_rfr); + geni_se_select_mode(&port->se, port->xfer_mode); + port->setup = true; + return 0; +} + +static int qcom_geni_serial_startup(struct uart_port *uport) +{ + int ret; + u32 proto; + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + + scnprintf(port->name, sizeof(port->name), + "qcom_serial_geni%d", uport->line); + + proto = geni_se_read_proto(&port->se); + if (proto != GENI_SE_UART) { + dev_err(uport->dev, "Invalid FW loaded, proto: %d\n", proto); + return -ENXIO; + } + + get_tx_fifo_size(port); + if (!port->setup) { + ret = qcom_geni_serial_port_setup(uport); + if (ret) + return ret; + } + + ret = request_irq(uport->irq, qcom_geni_serial_isr, IRQF_TRIGGER_HIGH, + port->name, uport); + if (ret) + dev_err(uport->dev, "Failed to get IRQ ret %d\n", ret); + return ret; +} + +static unsigned long get_clk_cfg(unsigned long clk_freq) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(root_freq); i++) { + if (!(root_freq[i] % clk_freq)) + return root_freq[i]; + } + return 0; +} + +static unsigned long get_clk_div_rate(unsigned int baud, unsigned int *clk_div) +{ + unsigned long ser_clk; + unsigned long desired_clk; + + desired_clk = baud * UART_OVERSAMPLING; + ser_clk = get_clk_cfg(desired_clk); + if (!ser_clk) { + pr_err("%s: Can't find matching DFS entry for baud %d\n", + __func__, baud); + return ser_clk; + } + + *clk_div = ser_clk / desired_clk; + return ser_clk; +} + +static void qcom_geni_serial_set_termios(struct uart_port *uport, + struct ktermios *termios, struct ktermios *old) +{ + unsigned int baud; + unsigned int bits_per_char; + unsigned int tx_trans_cfg; + unsigned int tx_parity_cfg; + unsigned int rx_trans_cfg; + unsigned int rx_parity_cfg; + unsigned int stop_bit_len; + unsigned int clk_div; + unsigned long ser_clk_cfg; + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + unsigned long clk_rate; + + qcom_geni_serial_stop_rx(uport); + /* baud rate */ + baud = uart_get_baud_rate(uport, termios, old, 300, 4000000); + port->baud = baud; + clk_rate = get_clk_div_rate(baud, &clk_div); + if (!clk_rate) + goto out_restart_rx; + + uport->uartclk = clk_rate; + clk_set_rate(port->se.clk, clk_rate); + ser_clk_cfg = SER_CLK_EN; + ser_clk_cfg |= clk_div << CLK_DIV_SHFT; + + /* parity */ + tx_trans_cfg = readl_relaxed(uport->membase + SE_UART_TX_TRANS_CFG); + tx_parity_cfg = readl_relaxed(uport->membase + SE_UART_TX_PARITY_CFG); + rx_trans_cfg = readl_relaxed(uport->membase + SE_UART_RX_TRANS_CFG); + rx_parity_cfg = readl_relaxed(uport->membase + SE_UART_RX_PARITY_CFG); + if (termios->c_cflag & PARENB) { + tx_trans_cfg |= UART_TX_PAR_EN; + rx_trans_cfg |= UART_RX_PAR_EN; + tx_parity_cfg |= PAR_CALC_EN; + rx_parity_cfg |= PAR_CALC_EN; + if (termios->c_cflag & PARODD) { + tx_parity_cfg |= PAR_ODD; + rx_parity_cfg |= PAR_ODD; + } else if (termios->c_cflag & CMSPAR) { + tx_parity_cfg |= PAR_SPACE; + rx_parity_cfg |= PAR_SPACE; + } else { + tx_parity_cfg |= PAR_EVEN; + rx_parity_cfg |= PAR_EVEN; + } + } else { + tx_trans_cfg &= ~UART_TX_PAR_EN; + rx_trans_cfg &= ~UART_RX_PAR_EN; + tx_parity_cfg &= ~PAR_CALC_EN; + rx_parity_cfg &= ~PAR_CALC_EN; + } + + /* bits per char */ + switch (termios->c_cflag & CSIZE) { + case CS5: + bits_per_char = 5; + break; + case CS6: + bits_per_char = 6; + break; + case CS7: + bits_per_char = 7; + break; + case CS8: + default: + bits_per_char = 8; + break; + } + + /* stop bits */ + if (termios->c_cflag & CSTOPB) + stop_bit_len = TX_STOP_BIT_LEN_2; + else + stop_bit_len = TX_STOP_BIT_LEN_1; + + /* flow control, clear the CTS_MASK bit if using flow control. */ + if (termios->c_cflag & CRTSCTS) + tx_trans_cfg &= ~UART_CTS_MASK; + else + tx_trans_cfg |= UART_CTS_MASK; + + if (baud) + uart_update_timeout(uport, termios->c_cflag, baud); + + writel_relaxed(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG); + writel_relaxed(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG); + writel_relaxed(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG); + writel_relaxed(rx_parity_cfg, uport->membase + SE_UART_RX_PARITY_CFG); + writel_relaxed(bits_per_char, uport->membase + SE_UART_TX_WORD_LEN); + writel_relaxed(bits_per_char, uport->membase + SE_UART_RX_WORD_LEN); + writel_relaxed(stop_bit_len, uport->membase + SE_UART_TX_STOP_BIT_LEN); + writel_relaxed(ser_clk_cfg, uport->membase + GENI_SER_M_CLK_CFG); + writel_relaxed(ser_clk_cfg, uport->membase + GENI_SER_S_CLK_CFG); +out_restart_rx: + qcom_geni_serial_start_rx(uport); +} + +static unsigned int qcom_geni_serial_tx_empty(struct uart_port *uport) +{ + return !readl_relaxed(uport->membase + SE_GENI_TX_FIFO_STATUS); +} + +#ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE +static int __init qcom_geni_console_setup(struct console *co, char *options) +{ + struct uart_port *uport; + struct qcom_geni_serial_port *port; + int baud; + int bits = 8; + int parity = 'n'; + int flow = 'n'; + + if (co->index >= GENI_UART_CONS_PORTS || co->index < 0) + return -ENXIO; + + port = get_port_from_line(co->index); + if (IS_ERR(port)) { + pr_err("Invalid line %d(%d)\n", co->index, (int)PTR_ERR(port)); + return PTR_ERR(port); + } + + uport = &port->uport; + + if (unlikely(!uport->membase)) + return -ENXIO; + + if (geni_se_resources_on(&port->se)) { + dev_err(port->se.dev, "Error turning on resources\n"); + return -ENXIO; + } + + if (unlikely(geni_se_read_proto(&port->se) != GENI_SE_UART)) { + geni_se_resources_off(&port->se); + return -ENXIO; + } + + if (!port->setup) { + port->tx_bytes_pw = 1; + port->rx_bytes_pw = RX_BYTES_PW; + qcom_geni_serial_stop_rx(uport); + qcom_geni_serial_port_setup(uport); + } + + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + + return uart_set_options(uport, co, baud, parity, bits, flow); +} + +static int __init console_register(struct uart_driver *drv) +{ + return uart_register_driver(drv); +} + +static void console_unregister(struct uart_driver *drv) +{ + uart_unregister_driver(drv); +} + +static struct console cons_ops = { + .name = "ttyMSM", + .write = qcom_geni_serial_console_write, + .device = uart_console_device, + .setup = qcom_geni_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &qcom_geni_console_driver, +}; + +static struct uart_driver qcom_geni_console_driver = { + .owner = THIS_MODULE, + .driver_name = "qcom_geni_console", + .dev_name = "ttyMSM", + .nr = GENI_UART_CONS_PORTS, + .cons = &cons_ops, +}; +#else +static int console_register(struct uart_driver *drv) +{ + return 0; +} + +static void console_unregister(struct uart_driver *drv) +{ +} +#endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */ + +static void qcom_geni_serial_cons_pm(struct uart_port *uport, + unsigned int new_state, unsigned int old_state) +{ + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + + if (unlikely(!uart_console(uport))) + return; + + if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF) + geni_se_resources_on(&port->se); + else if (new_state == UART_PM_STATE_OFF && + old_state == UART_PM_STATE_ON) + geni_se_resources_off(&port->se); +} + +static const struct uart_ops qcom_geni_console_pops = { + .tx_empty = qcom_geni_serial_tx_empty, + .stop_tx = qcom_geni_serial_stop_tx, + .start_tx = qcom_geni_serial_start_tx, + .stop_rx = qcom_geni_serial_stop_rx, + .set_termios = qcom_geni_serial_set_termios, + .startup = qcom_geni_serial_startup, + .request_port = qcom_geni_serial_request_port, + .config_port = qcom_geni_serial_config_port, + .shutdown = qcom_geni_serial_shutdown, + .type = qcom_geni_serial_get_type, + .set_mctrl = qcom_geni_cons_set_mctrl, + .get_mctrl = qcom_geni_cons_get_mctrl, +#ifdef CONFIG_CONSOLE_POLL + .poll_get_char = qcom_geni_serial_get_char, + .poll_put_char = qcom_geni_serial_poll_put_char, +#endif + .pm = qcom_geni_serial_cons_pm, +}; + +static int qcom_geni_serial_probe(struct platform_device *pdev) +{ + int ret = 0; + int line = -1; + struct qcom_geni_serial_port *port; + struct uart_port *uport; + struct resource *res; + + if (pdev->dev.of_node) + line = of_alias_get_id(pdev->dev.of_node, "serial"); + else + line = pdev->id; + + if (line < 0 || line >= GENI_UART_CONS_PORTS) + return -ENXIO; + port = get_port_from_line(line); + if (IS_ERR(port)) { + ret = PTR_ERR(port); + dev_err(&pdev->dev, "Invalid line %d(%d)\n", line, ret); + return ret; + } + + uport = &port->uport; + /* Don't allow 2 drivers to access the same port */ + if (uport->private_data) + return -ENODEV; + + uport->dev = &pdev->dev; + port->se.dev = &pdev->dev; + port->se.wrapper = dev_get_drvdata(pdev->dev.parent); + port->se.clk = devm_clk_get(&pdev->dev, "se"); + if (IS_ERR(port->se.clk)) { + ret = PTR_ERR(port->se.clk); + dev_err(&pdev->dev, "Err getting SE Core clk %d\n", ret); + return ret; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -EINVAL; + uport->mapbase = res->start; + + port->tx_fifo_depth = DEF_FIFO_DEPTH_WORDS; + port->rx_fifo_depth = DEF_FIFO_DEPTH_WORDS; + port->tx_fifo_width = DEF_FIFO_WIDTH_BITS; + + uport->irq = platform_get_irq(pdev, 0); + if (uport->irq < 0) { + dev_err(&pdev->dev, "Failed to get IRQ %d\n", uport->irq); + return uport->irq; + } + + uport->private_data = &qcom_geni_console_driver; + platform_set_drvdata(pdev, port); + port->handle_rx = handle_rx_console; + port->setup = false; + return uart_add_one_port(&qcom_geni_console_driver, uport); +} + +static int qcom_geni_serial_remove(struct platform_device *pdev) +{ + struct qcom_geni_serial_port *port = platform_get_drvdata(pdev); + struct uart_driver *drv = port->uport.private_data; + + uart_remove_one_port(drv, &port->uport); + return 0; +} + +static int __maybe_unused qcom_geni_serial_sys_suspend_noirq(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct qcom_geni_serial_port *port = platform_get_drvdata(pdev); + struct uart_port *uport = &port->uport; + + uart_suspend_port(uport->private_data, uport); + return 0; +} + +static int __maybe_unused qcom_geni_serial_sys_resume_noirq(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct qcom_geni_serial_port *port = platform_get_drvdata(pdev); + struct uart_port *uport = &port->uport; + + if (console_suspend_enabled && uport->suspended) { + uart_resume_port(uport->private_data, uport); + disable_irq(uport->irq); + } + return 0; +} + +static const struct dev_pm_ops qcom_geni_serial_pm_ops = { + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(qcom_geni_serial_sys_suspend_noirq, + qcom_geni_serial_sys_resume_noirq) +}; + +static const struct of_device_id qcom_geni_serial_match_table[] = { + { .compatible = "qcom,geni-debug-uart", }, + {} +}; +MODULE_DEVICE_TABLE(of, qcom_geni_serial_match_table); + +static struct platform_driver qcom_geni_serial_platform_driver = { + .remove = qcom_geni_serial_remove, + .probe = qcom_geni_serial_probe, + .driver = { + .name = "qcom_geni_serial", + .of_match_table = qcom_geni_serial_match_table, + .pm = &qcom_geni_serial_pm_ops, + }, +}; + +static int __init qcom_geni_serial_init(void) +{ + int ret; + + qcom_geni_console_port.uport.iotype = UPIO_MEM; + qcom_geni_console_port.uport.ops = &qcom_geni_console_pops; + qcom_geni_console_port.uport.flags = UPF_BOOT_AUTOCONF; + qcom_geni_console_port.uport.line = 0; + + ret = console_register(&qcom_geni_console_driver); + if (ret) + return ret; + + ret = platform_driver_register(&qcom_geni_serial_platform_driver); + if (ret) + console_unregister(&qcom_geni_console_driver); + return ret; +} +module_init(qcom_geni_serial_init); + +static void __exit qcom_geni_serial_exit(void) +{ + platform_driver_unregister(&qcom_geni_serial_platform_driver); + console_unregister(&qcom_geni_console_driver); +} +module_exit(qcom_geni_serial_exit); + +MODULE_DESCRIPTION("Serial driver for GENI based QUP cores"); +MODULE_LICENSE("GPL v2"); |