// SPDX-License-Identifier: GPL-2.0 /* sunzilog.c: Zilog serial driver for Sparc systems. * * Driver for Zilog serial chips found on Sun workstations and * servers. This driver could actually be made more generic. * * This is based on the old drivers/sbus/char/zs.c code. A lot * of code has been simply moved over directly from there but * much has been rewritten. Credits therefore go out to Eddie * C. Dost, Pete Zaitcev, Ted Ts'o and Alex Buell for their * work there. * * Copyright (C) 2002, 2006, 2007 David S. Miller (davem@davemloft.net) */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/errno.h> #include <linux/delay.h> #include <linux/tty.h> #include <linux/tty_flip.h> #include <linux/major.h> #include <linux/string.h> #include <linux/ptrace.h> #include <linux/ioport.h> #include <linux/slab.h> #include <linux/circ_buf.h> #include <linux/serial.h> #include <linux/sysrq.h> #include <linux/console.h> #include <linux/spinlock.h> #ifdef CONFIG_SERIO #include <linux/serio.h> #endif #include <linux/init.h> #include <linux/of.h> #include <linux/platform_device.h> #include <linux/io.h> #include <asm/irq.h> #include <asm/setup.h> #include <linux/serial_core.h> #include <linux/sunserialcore.h> #include "sunzilog.h" /* On 32-bit sparcs we need to delay after register accesses * to accommodate sun4 systems, but we do not need to flush writes. * On 64-bit sparc we only need to flush single writes to ensure * completion. */ #ifndef CONFIG_SPARC64 #define ZSDELAY() udelay(5) #define ZSDELAY_LONG() udelay(20) #define ZS_WSYNC(channel) do { } while (0) #else #define ZSDELAY() #define ZSDELAY_LONG() #define ZS_WSYNC(__channel) \ readb(&((__channel)->control)) #endif #define ZS_CLOCK 4915200 /* Zilog input clock rate. */ #define ZS_CLOCK_DIVISOR 16 /* Divisor this driver uses. */ /* * We wrap our port structure around the generic uart_port. */ struct uart_sunzilog_port { struct uart_port port; /* IRQ servicing chain. */ struct uart_sunzilog_port *next; /* Current values of Zilog write registers. */ unsigned char curregs[NUM_ZSREGS]; unsigned int flags; #define SUNZILOG_FLAG_CONS_KEYB 0x00000001 #define SUNZILOG_FLAG_CONS_MOUSE 0x00000002 #define SUNZILOG_FLAG_IS_CONS 0x00000004 #define SUNZILOG_FLAG_IS_KGDB 0x00000008 #define SUNZILOG_FLAG_MODEM_STATUS 0x00000010 #define SUNZILOG_FLAG_IS_CHANNEL_A 0x00000020 #define SUNZILOG_FLAG_REGS_HELD 0x00000040 #define SUNZILOG_FLAG_TX_STOPPED 0x00000080 #define SUNZILOG_FLAG_TX_ACTIVE 0x00000100 #define SUNZILOG_FLAG_ESCC 0x00000200 #define SUNZILOG_FLAG_ISR_HANDLER 0x00000400 unsigned int cflag; unsigned char parity_mask; unsigned char prev_status; #ifdef CONFIG_SERIO struct serio serio; int serio_open; #endif }; static void sunzilog_putchar(struct uart_port *port, unsigned char ch); #define ZILOG_CHANNEL_FROM_PORT(PORT) ((struct zilog_channel __iomem *)((PORT)->membase)) #define UART_ZILOG(PORT) ((struct uart_sunzilog_port *)(PORT)) #define ZS_IS_KEYB(UP) ((UP)->flags & SUNZILOG_FLAG_CONS_KEYB) #define ZS_IS_MOUSE(UP) ((UP)->flags & SUNZILOG_FLAG_CONS_MOUSE) #define ZS_IS_CONS(UP) ((UP)->flags & SUNZILOG_FLAG_IS_CONS) #define ZS_IS_KGDB(UP) ((UP)->flags & SUNZILOG_FLAG_IS_KGDB) #define ZS_WANTS_MODEM_STATUS(UP) ((UP)->flags & SUNZILOG_FLAG_MODEM_STATUS) #define ZS_IS_CHANNEL_A(UP) ((UP)->flags & SUNZILOG_FLAG_IS_CHANNEL_A) #define ZS_REGS_HELD(UP) ((UP)->flags & SUNZILOG_FLAG_REGS_HELD) #define ZS_TX_STOPPED(UP) ((UP)->flags & SUNZILOG_FLAG_TX_STOPPED) #define ZS_TX_ACTIVE(UP) ((UP)->flags & SUNZILOG_FLAG_TX_ACTIVE) /* Reading and writing Zilog8530 registers. The delays are to make this * driver work on the Sun4 which needs a settling delay after each chip * register access, other machines handle this in hardware via auxiliary * flip-flops which implement the settle time we do in software. * * The port lock must be held and local IRQs must be disabled * when {read,write}_zsreg is invoked. */ static unsigned char read_zsreg(struct zilog_channel __iomem *channel, unsigned char reg) { unsigned char retval; writeb(reg, &channel->control); ZSDELAY(); retval = readb(&channel->control); ZSDELAY(); return retval; } static void write_zsreg(struct zilog_channel __iomem *channel, unsigned char reg, unsigned char value) { writeb(reg, &channel->control); ZSDELAY(); writeb(value, &channel->control); ZSDELAY(); } static void sunzilog_clear_fifo(struct zilog_channel __iomem *channel) { int i; for (i = 0; i < 32; i++) { unsigned char regval; regval = readb(&channel->control); ZSDELAY(); if (regval & Rx_CH_AV) break; regval = read_zsreg(channel, R1); readb(&channel->data); ZSDELAY(); if (regval & (PAR_ERR | Rx_OVR | CRC_ERR)) { writeb(ERR_RES, &channel->control); ZSDELAY(); ZS_WSYNC(channel); } } } /* This function must only be called when the TX is not busy. The UART * port lock must be held and local interrupts disabled. */ static int __load_zsregs(struct zilog_channel __iomem *channel, unsigned char *regs) { int i; int escc; unsigned char r15; /* Let pending transmits finish. */ for (i = 0; i < 1000; i++) { unsigned char stat = read_zsreg(channel, R1); if (stat & ALL_SNT) break; udelay(100); } writeb(ERR_RES, &channel->control); ZSDELAY(); ZS_WSYNC(channel); sunzilog_clear_fifo(channel); /* Disable all interrupts. */ write_zsreg(channel, R1, regs[R1] & ~(RxINT_MASK | TxINT_ENAB | EXT_INT_ENAB)); /* Set parity, sync config, stop bits, and clock divisor. */ write_zsreg(channel, R4, regs[R4]); /* Set misc. TX/RX control bits. */ write_zsreg(channel, R10, regs[R10]); /* Set TX/RX controls sans the enable bits. */ write_zsreg(channel, R3, regs[R3] & ~RxENAB); write_zsreg(channel, R5, regs[R5] & ~TxENAB); /* Synchronous mode config. */ write_zsreg(channel, R6, regs[R6]); write_zsreg(channel, R7, regs[R7]); /* Don't mess with the interrupt vector (R2, unused by us) and * master interrupt control (R9). We make sure this is setup * properly at probe time then never touch it again. */ /* Disable baud generator. */ write_zsreg(channel, R14, regs[R14] & ~BRENAB); /* Clock mode control. */ write_zsreg(channel, R11, regs[R11]); /* Lower and upper byte of baud rate generator divisor. */ write_zsreg(channel, R12, regs[R12]); write_zsreg(channel, R13, regs[R13]); /* Now rewrite R14, with BRENAB (if set). */ write_zsreg(channel, R14, regs[R14]); /* External status interrupt control. */ write_zsreg(channel, R15, (regs[R15] | WR7pEN) & ~FIFOEN); /* ESCC Extension Register */ r15 = read_zsreg(channel, R15); if (r15 & 0x01) { write_zsreg(channel, R7, regs[R7p]); /* External status interrupt and FIFO control. */ write_zsreg(channel, R15, regs[R15] & ~WR7pEN); escc = 1; } else { /* Clear FIFO bit case it is an issue */ regs[R15] &= ~FIFOEN; escc = 0; } /* Reset external status interrupts. */ write_zsreg(channel, R0, RES_EXT_INT); /* First Latch */ write_zsreg(channel, R0, RES_EXT_INT); /* Second Latch */ /* Rewrite R3/R5, this time without enables masked. */ write_zsreg(channel, R3, regs[R3]); write_zsreg(channel, R5, regs[R5]); /* Rewrite R1, this time without IRQ enabled masked. */ write_zsreg(channel, R1, regs[R1]); return escc; } /* Reprogram the Zilog channel HW registers with the copies found in the * software state struct. If the transmitter is busy, we defer this update * until the next TX complete interrupt. Else, we do it right now. * * The UART port lock must be held and local interrupts disabled. */ static void sunzilog_maybe_update_regs(struct uart_sunzilog_port *up, struct zilog_channel __iomem *channel) { if (!ZS_REGS_HELD(up)) { if (ZS_TX_ACTIVE(up)) { up->flags |= SUNZILOG_FLAG_REGS_HELD; } else { __load_zsregs(channel, up->curregs); } } } static void sunzilog_change_mouse_baud(struct uart_sunzilog_port *up) { unsigned int cur_cflag = up->cflag; int brg, new_baud; up->cflag &= ~CBAUD; up->cflag |= suncore_mouse_baud_cflag_next(cur_cflag, &new_baud); brg = BPS_TO_BRG(new_baud, ZS_CLOCK / ZS_CLOCK_DIVISOR); up->curregs[R12] = (brg & 0xff); up->curregs[R13] = (brg >> 8) & 0xff; sunzilog_maybe_update_regs(up, ZILOG_CHANNEL_FROM_PORT(&up->port)); } static void sunzilog_kbdms_receive_chars(struct uart_sunzilog_port *up, unsigned char ch, int is_break) { if (ZS_IS_KEYB(up)) { /* Stop-A is handled by drivers/char/keyboard.c now. */ #ifdef CONFIG_SERIO if (up->serio_open) serio_interrupt(&up->serio, ch, 0); #endif } else if (ZS_IS_MOUSE(up)) { int ret = suncore_mouse_baud_detection(ch, is_break); switch (ret) { case 2: sunzilog_change_mouse_baud(up); fallthrough; case 1: break; case 0: #ifdef CONFIG_SERIO if (up->serio_open) serio_interrupt(&up->serio, ch, 0); #endif break; } } } static struct tty_port * sunzilog_receive_chars(struct uart_sunzilog_port *up, struct zilog_channel __iomem *channel) { struct tty_port *port = NULL; unsigned char ch, r1, flag; if (up->port.state != NULL) /* Unopened serial console */ port = &up->port.state->port; for (;;) { r1 = read_zsreg(channel, R1); if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) { writeb(ERR_RES, &channel->control); ZSDELAY(); ZS_WSYNC(channel); } ch = readb(&channel->control); ZSDELAY(); /* This funny hack depends upon BRK_ABRT not interfering * with the other bits we care about in R1. */ if (ch & BRK_ABRT) r1 |= BRK_ABRT; if (!(ch & Rx_CH_AV)) break; ch = readb(&channel->data); ZSDELAY(); ch &= up->parity_mask; if (unlikely(ZS_IS_KEYB(up)) || unlikely(ZS_IS_MOUSE(up))) { sunzilog_kbdms_receive_chars(up, ch, 0); continue; } /* A real serial line, record the character and status. */ flag = TTY_NORMAL; up->port.icount.rx++; if (r1 & (BRK_ABRT | PAR_ERR | Rx_OVR | CRC_ERR)) { if (r1 & BRK_ABRT) { r1 &= ~(PAR_ERR | CRC_ERR); up->port.icount.brk++; if (uart_handle_break(&up->port)) continue; } else if (r1 & PAR_ERR) up->port.icount.parity++; else if (r1 & CRC_ERR) up->port.icount.frame++; if (r1 & Rx_OVR) up->port.icount.overrun++; r1 &= up->port.read_status_mask; if (r1 & BRK_ABRT) flag = TTY_BREAK; else if (r1 & PAR_ERR) flag = TTY_PARITY; else if (r1 & CRC_ERR) flag = TTY_FRAME; } if (uart_handle_sysrq_char(&up->port, ch) || !port) continue; if (up->port.ignore_status_mask == 0xff || (r1 & up->port.ignore_status_mask) == 0) { tty_insert_flip_char(port, ch, flag); } if (r1 & Rx_OVR) tty_insert_flip_char(port, 0, TTY_OVERRUN); } return port; } static void sunzilog_status_handle(struct uart_sunzilog_port *up, struct zilog_channel __iomem *channel) { unsigned char status; status = readb(&channel->control); ZSDELAY(); writeb(RES_EXT_INT, &channel->control); ZSDELAY(); ZS_WSYNC(channel); if (status & BRK_ABRT) { if (ZS_IS_MOUSE(up)) sunzilog_kbdms_receive_chars(up, 0, 1); if (ZS_IS_CONS(up)) { /* Wait for BREAK to deassert to avoid potentially * confusing the PROM. */ while (1) { status = readb(&channel->control); ZSDELAY(); if (!(status & BRK_ABRT)) break; } sun_do_break(); return; } } if (ZS_WANTS_MODEM_STATUS(up)) { if (status & SYNC) up->port.icount.dsr++; /* The Zilog just gives us an interrupt when DCD/CTS/etc. change. * But it does not tell us which bit has changed, we have to keep * track of this ourselves. */ if ((status ^ up->prev_status) ^ DCD) uart_handle_dcd_change(&up->port, (status & DCD)); if ((status ^ up->prev_status) ^ CTS) uart_handle_cts_change(&up->port, (status & CTS)); wake_up_interruptible(&up->port.state->port.delta_msr_wait); } up->prev_status = status; } static void sunzilog_transmit_chars(struct uart_sunzilog_port *up, struct zilog_channel __iomem *channel) { struct circ_buf *xmit; if (ZS_IS_CONS(up)) { unsigned char status = readb(&channel->control); ZSDELAY(); /* TX still busy? Just wait for the next TX done interrupt. * * It can occur because of how we do serial console writes. It would * be nice to transmit console writes just like we normally would for * a TTY line. (ie. buffered and TX interrupt driven). That is not * easy because console writes cannot sleep. One solution might be * to poll on enough port->xmit space becoming free. -DaveM */ if (!(status & Tx_BUF_EMP)) return; } up->flags &= ~SUNZILOG_FLAG_TX_ACTIVE; if (ZS_REGS_HELD(up)) { __load_zsregs(channel, up->curregs); up->flags &= ~SUNZILOG_FLAG_REGS_HELD; } if (ZS_TX_STOPPED(up)) { up->flags &= ~SUNZILOG_FLAG_TX_STOPPED; goto ack_tx_int; } if (up->port.x_char) { up->flags |= SUNZILOG_FLAG_TX_ACTIVE; writeb(up->port.x_char, &channel->data); ZSDELAY(); ZS_WSYNC(channel); up->port.icount.tx++; up->port.x_char = 0; return; } if (up->port.state == NULL) goto ack_tx_int; xmit = &up->port.state->xmit; if (uart_circ_empty(xmit)) goto ack_tx_int; if (uart_tx_stopped(&up->port)) goto ack_tx_int; up->flags |= SUNZILOG_FLAG_TX_ACTIVE; writeb(xmit->buf[xmit->tail], &channel->data); ZSDELAY(); ZS_WSYNC(channel); uart_xmit_advance(&up->port, 1); if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(&up->port); return; ack_tx_int: writeb(RES_Tx_P, &channel->control); ZSDELAY(); ZS_WSYNC(channel); } static irqreturn_t sunzilog_interrupt(int irq, void *dev_id) { struct uart_sunzilog_port *up = dev_id; while (up) { struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(&up->port); struct tty_port *port; unsigned char r3; spin_lock(&up->port.lock); r3 = read_zsreg(channel, R3); /* Channel A */ port = NULL; if (r3 & (CHAEXT | CHATxIP | CHARxIP)) { writeb(RES_H_IUS, &channel->control); ZSDELAY(); ZS_WSYNC(channel); if (r3 & CHARxIP) port = sunzilog_receive_chars(up, channel); if (r3 & CHAEXT) sunzilog_status_handle(up, channel); if (r3 & CHATxIP) sunzilog_transmit_chars(up, channel); } spin_unlock(&up->port.lock); if (port) tty_flip_buffer_push(port); /* Channel B */ up = up->next; channel = ZILOG_CHANNEL_FROM_PORT(&up->port); spin_lock(&up->port.lock); port = NULL; if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) { writeb(RES_H_IUS, &channel->control); ZSDELAY(); ZS_WSYNC(channel); if (r3 & CHBRxIP) port = sunzilog_receive_chars(up, channel); if (r3 & CHBEXT) sunzilog_status_handle(up, channel); if (r3 & CHBTxIP) sunzilog_transmit_chars(up, channel); } spin_unlock(&up->port.lock); if (port) tty_flip_buffer_push(port); up = up->next; } return IRQ_HANDLED; } /* A convenient way to quickly get R0 status. The caller must _not_ hold the * port lock, it is acquired here. */ static __inline__ unsigned char sunzilog_read_channel_status(struct uart_port *port) { struct zilog_channel __iomem *channel; unsigned char status; channel = ZILOG_CHANNEL_FROM_PORT(port); status = readb(&channel->control); ZSDELAY(); return status; } /* The port lock is not held. */ static unsigned int sunzilog_tx_empty(struct uart_port *port) { unsigned long flags; unsigned char status; unsigned int ret; spin_lock_irqsave(&port->lock, flags); status = sunzilog_read_channel_status(port); spin_unlock_irqrestore(&port->lock, flags); if (status & Tx_BUF_EMP) ret = TIOCSER_TEMT; else ret = 0; return ret; } /* The port lock is held and interrupts are disabled. */ static unsigned int sunzilog_get_mctrl(struct uart_port *port) { unsigned char status; unsigned int ret; status = sunzilog_read_channel_status(port); ret = 0; if (status & DCD) ret |= TIOCM_CAR; if (status & SYNC) ret |= TIOCM_DSR; if (status & CTS) ret |= TIOCM_CTS; return ret; } /* The port lock is held and interrupts are disabled. */ static void sunzilog_set_mctrl(struct uart_port *port, unsigned int mctrl) { struct uart_sunzilog_port *up = container_of(port, struct uart_sunzilog_port, port); struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port); unsigned char set_bits, clear_bits; set_bits = clear_bits = 0; if (mctrl & TIOCM_RTS) set_bits |= RTS; else clear_bits |= RTS; if (mctrl & TIOCM_DTR) set_bits |= DTR; else clear_bits |= DTR; /* NOTE: Not subject to 'transmitter active' rule. */ up->curregs[R5] |= set_bits; up->curregs[R5] &= ~clear_bits; write_zsreg(channel, R5, up->curregs[R5]); } /* The port lock is held and interrupts are disabled. */ static void sunzilog_stop_tx(struct uart_port *port) { struct uart_sunzilog_port *up = container_of(port, struct uart_sunzilog_port, port); up->flags |= SUNZILOG_FLAG_TX_STOPPED; } /* The port lock is held and interrupts are disabled. */ static void sunzilog_start_tx(struct uart_port *port) { struct uart_sunzilog_port *up = container_of(port, struct uart_sunzilog_port, port); struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port); unsigned char status; up->flags |= SUNZILOG_FLAG_TX_ACTIVE; up->flags &= ~SUNZILOG_FLAG_TX_STOPPED; status = readb(&channel->control); ZSDELAY(); /* TX busy? Just wait for the TX done interrupt. */ if (!(status & Tx_BUF_EMP)) return; /* Send the first character to jump-start the TX done * IRQ sending engine. */ if (port->x_char) { writeb(port->x_char, &channel->data); ZSDELAY(); ZS_WSYNC(channel); port->icount.tx++; port->x_char = 0; } else { struct circ_buf *xmit = &port->state->xmit; if (uart_circ_empty(xmit)) return; writeb(xmit->buf[xmit->tail], &channel->data); ZSDELAY(); ZS_WSYNC(channel); uart_xmit_advance(port, 1); if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(&up->port); } } /* The port lock is held. */ static void sunzilog_stop_rx(struct uart_port *port) { struct uart_sunzilog_port *up = UART_ZILOG(port); struct zilog_channel __iomem *channel; if (ZS_IS_CONS(up)) return; channel = ZILOG_CHANNEL_FROM_PORT(port); /* Disable all RX interrupts. */ up->curregs[R1] &= ~RxINT_MASK; sunzilog_maybe_update_regs(up, channel); } /* The port lock is held. */ static void sunzilog_enable_ms(struct uart_port *port) { struct uart_sunzilog_port *up = container_of(port, struct uart_sunzilog_port, port); struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port); unsigned char new_reg; new_reg = up->curregs[R15] | (DCDIE | SYNCIE | CTSIE); if (new_reg != up->curregs[R15]) { up->curregs[R15] = new_reg; /* NOTE: Not subject to 'transmitter active' rule. */ write_zsreg(channel, R15, up->curregs[R15] & ~WR7pEN); } } /* The port lock is not held. */ static void sunzilog_break_ctl(struct uart_port *port, int break_state) { struct uart_sunzilog_port *up = container_of(port, struct uart_sunzilog_port, port); struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port); unsigned char set_bits, clear_bits, new_reg; unsigned long flags; set_bits = clear_bits = 0; if (break_state) set_bits |= SND_BRK; else clear_bits |= SND_BRK; spin_lock_irqsave(&port->lock, flags); new_reg = (up->curregs[R5] | set_bits) & ~clear_bits; if (new_reg != up->curregs[R5]) { up->curregs[R5] = new_reg; /* NOTE: Not subject to 'transmitter active' rule. */ write_zsreg(channel, R5, up->curregs[R5]); } spin_unlock_irqrestore(&port->lock, flags); } static void __sunzilog_startup(struct uart_sunzilog_port *up) { struct zilog_channel __iomem *channel; channel = ZILOG_CHANNEL_FROM_PORT(&up->port); up->prev_status = readb(&channel->control); /* Enable receiver and transmitter. */ up->curregs[R3] |= RxENAB; up->curregs[R5] |= TxENAB; up->curregs[R1] |= EXT_INT_ENAB | INT_ALL_Rx | TxINT_ENAB; sunzilog_maybe_update_regs(up, channel); } static int sunzilog_startup(struct uart_port *port) { struct uart_sunzilog_port *up = UART_ZILOG(port); unsigned long flags; if (ZS_IS_CONS(up)) return 0; spin_lock_irqsave(&port->lock, flags); __sunzilog_startup(up); spin_unlock_irqrestore(&port->lock, flags); return 0; } /* * The test for ZS_IS_CONS is explained by the following e-mail: ***** * From: Russell King <rmk@arm.linux.org.uk> * Date: Sun, 8 Dec 2002 10:18:38 +0000 * * On Sun, Dec 08, 2002 at 02:43:36AM -0500, Pete Zaitcev wrote: * > I boot my 2.5 boxes using "console=ttyS0,9600" argument, * > and I noticed that something is not right with reference * > counting in this case. It seems that when the console * > is open by kernel initially, this is not accounted * > as an open, and uart_startup is not called. * * That is correct. We are unable to call uart_startup when the serial * console is initialised because it may need to allocate memory (as * request_irq does) and the memory allocators may not have been * initialised. * * 1. initialise the port into a state where it can send characters in the * console write method. * * 2. don't do the actual hardware shutdown in your shutdown() method (but * do the normal software shutdown - ie, free irqs etc) ***** */ static void sunzilog_shutdown(struct uart_port *port) { struct uart_sunzilog_port *up = UART_ZILOG(port); struct zilog_channel __iomem *channel; unsigned long flags; if (ZS_IS_CONS(up)) return; spin_lock_irqsave(&port->lock, flags); channel = ZILOG_CHANNEL_FROM_PORT(port); /* Disable receiver and transmitter. */ up->curregs[R3] &= ~RxENAB; up->curregs[R5] &= ~TxENAB; /* Disable all interrupts and BRK assertion. */ up->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK); up->curregs[R5] &= ~SND_BRK; sunzilog_maybe_update_regs(up, channel); spin_unlock_irqrestore(&port->lock, flags); } /* Shared by TTY driver and serial console setup. The port lock is held * and local interrupts are disabled. */ static void sunzilog_convert_to_zs(struct uart_sunzilog_port *up, unsigned int cflag, unsigned int iflag, int brg) { up->curregs[R10] = NRZ; up->curregs[R11] = TCBR | RCBR; /* Program BAUD and clock source. */ up->curregs[R4] &= ~XCLK_MASK; up->curregs[R4] |= X16CLK; up->curregs[R12] = brg & 0xff; up->curregs[R13] = (brg >> 8) & 0xff; up->curregs[R14] = BRSRC | BRENAB; /* Character size, stop bits, and parity. */ up->curregs[R3] &= ~RxN_MASK; up->curregs[R5] &= ~TxN_MASK; switch (cflag & CSIZE) { case CS5: up->curregs[R3] |= Rx5; up->curregs[R5] |= Tx5; up->parity_mask = 0x1f; break; case CS6: up->curregs[R3] |= Rx6; up->curregs[R5] |= Tx6; up->parity_mask = 0x3f; break; case CS7: up->curregs[R3] |= Rx7; up->curregs[R5] |= Tx7; up->parity_mask = 0x7f; break; case CS8: default: up->curregs[R3] |= Rx8; up->curregs[R5] |= Tx8; up->parity_mask = 0xff; break; } up->curregs[R4] &= ~0x0c; if (cflag & CSTOPB) up->curregs[R4] |= SB2; else up->curregs[R4] |= SB1; if (cflag & PARENB) up->curregs[R4] |= PAR_ENAB; else up->curregs[R4] &= ~PAR_ENAB; if (!(cflag & PARODD)) up->curregs[R4] |= PAR_EVEN; else up->curregs[R4] &= ~PAR_EVEN; up->port.read_status_mask = Rx_OVR; if (iflag & INPCK) up->port.read_status_mask |= CRC_ERR | PAR_ERR; if (iflag & (IGNBRK | BRKINT | PARMRK)) up->port.read_status_mask |= BRK_ABRT; up->port.ignore_status_mask = 0; if (iflag & IGNPAR) up->port.ignore_status_mask |= CRC_ERR | PAR_ERR; if (iflag & IGNBRK) { up->port.ignore_status_mask |= BRK_ABRT; if (iflag & IGNPAR) up->port.ignore_status_mask |= Rx_OVR; } if ((cflag & CREAD) == 0) up->port.ignore_status_mask = 0xff; } /* The port lock is not held. */ static void sunzilog_set_termios(struct uart_port *port, struct ktermios *termios, const struct ktermios *old) { struct uart_sunzilog_port *up = container_of(port, struct uart_sunzilog_port, port); unsigned long flags; int baud, brg; baud = uart_get_baud_rate(port, termios, old, 1200, 76800); spin_lock_irqsave(&up->port.lock, flags); brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR); sunzilog_convert_to_zs(up, termios->c_cflag, termios->c_iflag, brg); if (UART_ENABLE_MS(&up->port, termios->c_cflag)) up->flags |= SUNZILOG_FLAG_MODEM_STATUS; else up->flags &= ~SUNZILOG_FLAG_MODEM_STATUS; up->cflag = termios->c_cflag; sunzilog_maybe_update_regs(up, ZILOG_CHANNEL_FROM_PORT(port)); uart_update_timeout(port, termios->c_cflag, baud); spin_unlock_irqrestore(&up->port.lock, flags); } static const char *sunzilog_type(struct uart_port *port) { struct uart_sunzilog_port *up = UART_ZILOG(port); return (up->flags & SUNZILOG_FLAG_ESCC) ? "zs (ESCC)" : "zs"; } /* We do not request/release mappings of the registers here, this * happens at early serial probe time. */ static void sunzilog_release_port(struct uart_port *port) { } static int sunzilog_request_port(struct uart_port *port) { return 0; } /* These do not need to do anything interesting either. */ static void sunzilog_config_port(struct uart_port *port, int flags) { } /* We do not support letting the user mess with the divisor, IRQ, etc. */ static int sunzilog_verify_port(struct uart_port *port, struct serial_struct *ser) { return -EINVAL; } #ifdef CONFIG_CONSOLE_POLL static int sunzilog_get_poll_char(struct uart_port *port) { unsigned char ch, r1; struct uart_sunzilog_port *up = container_of(port, struct uart_sunzilog_port, port); struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(&up->port); r1 = read_zsreg(channel, R1); if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) { writeb(ERR_RES, &channel->control); ZSDELAY(); ZS_WSYNC(channel); } ch = readb(&channel->control); ZSDELAY(); /* This funny hack depends upon BRK_ABRT not interfering * with the other bits we care about in R1. */ if (ch & BRK_ABRT) r1 |= BRK_ABRT; if (!(ch & Rx_CH_AV)) return NO_POLL_CHAR; ch = readb(&channel->data); ZSDELAY(); ch &= up->parity_mask; return ch; } static void sunzilog_put_poll_char(struct uart_port *port, unsigned char ch) { struct uart_sunzilog_port *up = container_of(port, struct uart_sunzilog_port, port); sunzilog_putchar(&up->port, ch); } #endif /* CONFIG_CONSOLE_POLL */ static const struct uart_ops sunzilog_pops = { .tx_empty = sunzilog_tx_empty, .set_mctrl = sunzilog_set_mctrl, .get_mctrl = sunzilog_get_mctrl, .stop_tx = sunzilog_stop_tx, .start_tx = sunzilog_start_tx, .stop_rx = sunzilog_stop_rx, .enable_ms = sunzilog_enable_ms, .break_ctl = sunzilog_break_ctl, .startup = sunzilog_startup, .shutdown = sunzilog_shutdown, .set_termios = sunzilog_set_termios, .type = sunzilog_type, .release_port = sunzilog_release_port, .request_port = sunzilog_request_port, .config_port = sunzilog_config_port, .verify_port = sunzilog_verify_port, #ifdef CONFIG_CONSOLE_POLL .poll_get_char = sunzilog_get_poll_char, .poll_put_char = sunzilog_put_poll_char, #endif }; static int uart_chip_count; static struct uart_sunzilog_port *sunzilog_port_table; static struct zilog_layout __iomem **sunzilog_chip_regs; static struct uart_sunzilog_port *sunzilog_irq_chain; static struct uart_driver sunzilog_reg = { .owner = THIS_MODULE, .driver_name = "sunzilog", .dev_name = "ttyS", .major = TTY_MAJOR, }; static int __init sunzilog_alloc_tables(int num_sunzilog) { struct uart_sunzilog_port *up; unsigned long size; int num_channels = num_sunzilog * 2; int i; size = num_channels * sizeof(struct uart_sunzilog_port); sunzilog_port_table = kzalloc(size, GFP_KERNEL); if (!sunzilog_port_table) return -ENOMEM; for (i = 0; i < num_channels; i++) { up = &sunzilog_port_table[i]; spin_lock_init(&up->port.lock); if (i == 0) sunzilog_irq_chain = up; if (i < num_channels - 1) up->next = up + 1; else up->next = NULL; } size = num_sunzilog * sizeof(struct zilog_layout __iomem *); sunzilog_chip_regs = kzalloc(size, GFP_KERNEL); if (!sunzilog_chip_regs) { kfree(sunzilog_port_table); sunzilog_irq_chain = NULL; return -ENOMEM; } return 0; } static void sunzilog_free_tables(void) { kfree(sunzilog_port_table); sunzilog_irq_chain = NULL; kfree(sunzilog_chip_regs); } #define ZS_PUT_CHAR_MAX_DELAY 2000 /* 10 ms */ static void __maybe_unused sunzilog_putchar(struct uart_port *port, unsigned char ch) { struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port); int loops = ZS_PUT_CHAR_MAX_DELAY; /* This is a timed polling loop so do not switch the explicit * udelay with ZSDELAY as that is a NOP on some platforms. -DaveM */ do { unsigned char val = readb(&channel->control); if (val & Tx_BUF_EMP) { ZSDELAY(); break; } udelay(5); } while (--loops); writeb(ch, &channel->data); ZSDELAY(); ZS_WSYNC(channel); } #ifdef CONFIG_SERIO static DEFINE_SPINLOCK(sunzilog_serio_lock); static int sunzilog_serio_write(struct serio *serio, unsigned char ch) { struct uart_sunzilog_port *up = serio->port_data; unsigned long flags; spin_lock_irqsave(&sunzilog_serio_lock, flags); sunzilog_putchar(&up->port, ch); spin_unlock_irqrestore(&sunzilog_serio_lock, flags); return 0; } static int sunzilog_serio_open(struct serio *serio) { struct uart_sunzilog_port *up = serio->port_data; unsigned long flags; int ret; spin_lock_irqsave(&sunzilog_serio_lock, flags); if (!up->serio_open) { up->serio_open = 1; ret = 0; } else ret = -EBUSY; spin_unlock_irqrestore(&sunzilog_serio_lock, flags); return ret; } static void sunzilog_serio_close(struct serio *serio) { struct uart_sunzilog_port *up = serio->port_data; unsigned long flags; spin_lock_irqsave(&sunzilog_serio_lock, flags); up->serio_open = 0; spin_unlock_irqrestore(&sunzilog_serio_lock, flags); } #endif /* CONFIG_SERIO */ #ifdef CONFIG_SERIAL_SUNZILOG_CONSOLE static void sunzilog_console_write(struct console *con, const char *s, unsigned int count) { struct uart_sunzilog_port *up = &sunzilog_port_table[con->index]; unsigned long flags; int locked = 1; if (up->port.sysrq || oops_in_progress) locked = spin_trylock_irqsave(&up->port.lock, flags); else spin_lock_irqsave(&up->port.lock, flags); uart_console_write(&up->port, s, count, sunzilog_putchar); udelay(2); if (locked) spin_unlock_irqrestore(&up->port.lock, flags); } static int __init sunzilog_console_setup(struct console *con, char *options) { struct uart_sunzilog_port *up = &sunzilog_port_table[con->index]; unsigned long flags; int baud, brg; if (up->port.type != PORT_SUNZILOG) return -EINVAL; printk(KERN_INFO "Console: ttyS%d (SunZilog zs%d)\n", (sunzilog_reg.minor - 64) + con->index, con->index); /* Get firmware console settings. */ sunserial_console_termios(con, up->port.dev->of_node); /* Firmware console speed is limited to 150-->38400 baud so * this hackish cflag thing is OK. */ switch (con->cflag & CBAUD) { case B150: baud = 150; break; case B300: baud = 300; break; case B600: baud = 600; break; case B1200: baud = 1200; break; case B2400: baud = 2400; break; case B4800: baud = 4800; break; default: case B9600: baud = 9600; break; case B19200: baud = 19200; break; case B38400: baud = 38400; break; } brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR); spin_lock_irqsave(&up->port.lock, flags); up->curregs[R15] |= BRKIE; sunzilog_convert_to_zs(up, con->cflag, 0, brg); sunzilog_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS); __sunzilog_startup(up); spin_unlock_irqrestore(&up->port.lock, flags); return 0; } static struct console sunzilog_console_ops = { .name = "ttyS", .write = sunzilog_console_write, .device = uart_console_device, .setup = sunzilog_console_setup, .flags = CON_PRINTBUFFER, .index = -1, .data = &sunzilog_reg, }; static inline struct console *SUNZILOG_CONSOLE(void) { return &sunzilog_console_ops; } #else #define SUNZILOG_CONSOLE() (NULL) #endif static void sunzilog_init_kbdms(struct uart_sunzilog_port *up) { int baud, brg; if (up->flags & SUNZILOG_FLAG_CONS_KEYB) { up->cflag = B1200 | CS8 | CLOCAL | CREAD; baud = 1200; } else { up->cflag = B4800 | CS8 | CLOCAL | CREAD; baud = 4800; } up->curregs[R15] |= BRKIE; brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR); sunzilog_convert_to_zs(up, up->cflag, 0, brg); sunzilog_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS); __sunzilog_startup(up); } #ifdef CONFIG_SERIO static void sunzilog_register_serio(struct uart_sunzilog_port *up) { struct serio *serio = &up->serio; serio->port_data = up; serio->id.type = SERIO_RS232; if (up->flags & SUNZILOG_FLAG_CONS_KEYB) { serio->id.proto = SERIO_SUNKBD; strscpy(serio->name, "zskbd", sizeof(serio->name)); } else { serio->id.proto = SERIO_SUN; serio->id.extra = 1; strscpy(serio->name, "zsms", sizeof(serio->name)); } strscpy(serio->phys, ((up->flags & SUNZILOG_FLAG_CONS_KEYB) ? "zs/serio0" : "zs/serio1"), sizeof(serio->phys)); serio->write = sunzilog_serio_write; serio->open = sunzilog_serio_open; serio->close = sunzilog_serio_close; serio->dev.parent = up->port.dev; serio_register_port(serio); } #endif static void sunzilog_init_hw(struct uart_sunzilog_port *up) { struct zilog_channel __iomem *channel; unsigned long flags; int baud, brg; channel = ZILOG_CHANNEL_FROM_PORT(&up->port); spin_lock_irqsave(&up->port.lock, flags); if (ZS_IS_CHANNEL_A(up)) { write_zsreg(channel, R9, FHWRES); ZSDELAY_LONG(); (void) read_zsreg(channel, R0); } if (up->flags & (SUNZILOG_FLAG_CONS_KEYB | SUNZILOG_FLAG_CONS_MOUSE)) { up->curregs[R1] = EXT_INT_ENAB | INT_ALL_Rx | TxINT_ENAB; up->curregs[R4] = PAR_EVEN | X16CLK | SB1; up->curregs[R3] = RxENAB | Rx8; up->curregs[R5] = TxENAB | Tx8; up->curregs[R6] = 0x00; /* SDLC Address */ up->curregs[R7] = 0x7E; /* SDLC Flag */ up->curregs[R9] = NV; up->curregs[R7p] = 0x00; sunzilog_init_kbdms(up); /* Only enable interrupts if an ISR handler available */ if (up->flags & SUNZILOG_FLAG_ISR_HANDLER) up->curregs[R9] |= MIE; write_zsreg(channel, R9, up->curregs[R9]); } else { /* Normal serial TTY. */ up->parity_mask = 0xff; up->curregs[R1] = EXT_INT_ENAB | INT_ALL_Rx | TxINT_ENAB; up->curregs[R4] = PAR_EVEN | X16CLK | SB1; up->curregs[R3] = RxENAB | Rx8; up->curregs[R5] = TxENAB | Tx8; up->curregs[R6] = 0x00; /* SDLC Address */ up->curregs[R7] = 0x7E; /* SDLC Flag */ up->curregs[R9] = NV; up->curregs[R10] = NRZ; up->curregs[R11] = TCBR | RCBR; baud = 9600; brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR); up->curregs[R12] = (brg & 0xff); up->curregs[R13] = (brg >> 8) & 0xff; up->curregs[R14] = BRSRC | BRENAB; up->curregs[R15] = FIFOEN; /* Use FIFO if on ESCC */ up->curregs[R7p] = TxFIFO_LVL | RxFIFO_LVL; if (__load_zsregs(channel, up->curregs)) { up->flags |= SUNZILOG_FLAG_ESCC; } /* Only enable interrupts if an ISR handler available */ if (up->flags & SUNZILOG_FLAG_ISR_HANDLER) up->curregs[R9] |= MIE; write_zsreg(channel, R9, up->curregs[R9]); } spin_unlock_irqrestore(&up->port.lock, flags); #ifdef CONFIG_SERIO if (up->flags & (SUNZILOG_FLAG_CONS_KEYB | SUNZILOG_FLAG_CONS_MOUSE)) sunzilog_register_serio(up); #endif } static int zilog_irq; static int zs_probe(struct platform_device *op) { static int kbm_inst, uart_inst; int inst; struct uart_sunzilog_port *up; struct zilog_layout __iomem *rp; int keyboard_mouse = 0; int err; if (of_property_present(op->dev.of_node, "keyboard")) keyboard_mouse = 1; /* uarts must come before keyboards/mice */ if (keyboard_mouse) inst = uart_chip_count + kbm_inst; else inst = uart_inst; sunzilog_chip_regs[inst] = of_ioremap(&op->resource[0], 0, sizeof(struct zilog_layout), "zs"); if (!sunzilog_chip_regs[inst]) return -ENOMEM; rp = sunzilog_chip_regs[inst]; if (!zilog_irq) zilog_irq = op->archdata.irqs[0]; up = &sunzilog_port_table[inst * 2]; /* Channel A */ up[0].port.mapbase = op->resource[0].start + 0x00; up[0].port.membase = (void __iomem *) &rp->channelA; up[0].port.iotype = UPIO_MEM; up[0].port.irq = op->archdata.irqs[0]; up[0].port.uartclk = ZS_CLOCK; up[0].port.fifosize = 1; up[0].port.ops = &sunzilog_pops; up[0].port.type = PORT_SUNZILOG; up[0].port.flags = 0; up[0].port.line = (inst * 2) + 0; up[0].port.dev = &op->dev; up[0].flags |= SUNZILOG_FLAG_IS_CHANNEL_A; up[0].port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SUNZILOG_CONSOLE); if (keyboard_mouse) up[0].flags |= SUNZILOG_FLAG_CONS_KEYB; sunzilog_init_hw(&up[0]); /* Channel B */ up[1].port.mapbase = op->resource[0].start + 0x04; up[1].port.membase = (void __iomem *) &rp->channelB; up[1].port.iotype = UPIO_MEM; up[1].port.irq = op->archdata.irqs[0]; up[1].port.uartclk = ZS_CLOCK; up[1].port.fifosize = 1; up[1].port.ops = &sunzilog_pops; up[1].port.type = PORT_SUNZILOG; up[1].port.flags = 0; up[1].port.line = (inst * 2) + 1; up[1].port.dev = &op->dev; up[1].flags |= 0; up[1].port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SUNZILOG_CONSOLE); if (keyboard_mouse) up[1].flags |= SUNZILOG_FLAG_CONS_MOUSE; sunzilog_init_hw(&up[1]); if (!keyboard_mouse) { if (sunserial_console_match(SUNZILOG_CONSOLE(), op->dev.of_node, &sunzilog_reg, up[0].port.line, false)) up->flags |= SUNZILOG_FLAG_IS_CONS; err = uart_add_one_port(&sunzilog_reg, &up[0].port); if (err) { of_iounmap(&op->resource[0], rp, sizeof(struct zilog_layout)); return err; } if (sunserial_console_match(SUNZILOG_CONSOLE(), op->dev.of_node, &sunzilog_reg, up[1].port.line, false)) up->flags |= SUNZILOG_FLAG_IS_CONS; err = uart_add_one_port(&sunzilog_reg, &up[1].port); if (err) { uart_remove_one_port(&sunzilog_reg, &up[0].port); of_iounmap(&op->resource[0], rp, sizeof(struct zilog_layout)); return err; } uart_inst++; } else { printk(KERN_INFO "%s: Keyboard at MMIO 0x%llx (irq = %d) " "is a %s\n", dev_name(&op->dev), (unsigned long long) up[0].port.mapbase, op->archdata.irqs[0], sunzilog_type(&up[0].port)); printk(KERN_INFO "%s: Mouse at MMIO 0x%llx (irq = %d) " "is a %s\n", dev_name(&op->dev), (unsigned long long) up[1].port.mapbase, op->archdata.irqs[0], sunzilog_type(&up[1].port)); kbm_inst++; } platform_set_drvdata(op, &up[0]); return 0; } static void zs_remove_one(struct uart_sunzilog_port *up) { if (ZS_IS_KEYB(up) || ZS_IS_MOUSE(up)) { #ifdef CONFIG_SERIO serio_unregister_port(&up->serio); #endif } else uart_remove_one_port(&sunzilog_reg, &up->port); } static int zs_remove(struct platform_device *op) { struct uart_sunzilog_port *up = platform_get_drvdata(op); struct zilog_layout __iomem *regs; zs_remove_one(&up[0]); zs_remove_one(&up[1]); regs = sunzilog_chip_regs[up[0].port.line / 2]; of_iounmap(&op->resource[0], regs, sizeof(struct zilog_layout)); return 0; } static const struct of_device_id zs_match[] = { { .name = "zs", }, {}, }; MODULE_DEVICE_TABLE(of, zs_match); static struct platform_driver zs_driver = { .driver = { .name = "zs", .of_match_table = zs_match, }, .probe = zs_probe, .remove = zs_remove, }; static int __init sunzilog_init(void) { struct device_node *dp; int err; int num_keybms = 0; int num_sunzilog = 0; for_each_node_by_name(dp, "zs") { num_sunzilog++; if (of_property_present(dp, "keyboard")) num_keybms++; } if (num_sunzilog) { err = sunzilog_alloc_tables(num_sunzilog); if (err) goto out; uart_chip_count = num_sunzilog - num_keybms; err = sunserial_register_minors(&sunzilog_reg, uart_chip_count * 2); if (err) goto out_free_tables; } err = platform_driver_register(&zs_driver); if (err) goto out_unregister_uart; if (zilog_irq) { struct uart_sunzilog_port *up = sunzilog_irq_chain; err = request_irq(zilog_irq, sunzilog_interrupt, IRQF_SHARED, "zs", sunzilog_irq_chain); if (err) goto out_unregister_driver; /* Enable Interrupts */ while (up) { struct zilog_channel __iomem *channel; /* printk (KERN_INFO "Enable IRQ for ZILOG Hardware %p\n", up); */ channel = ZILOG_CHANNEL_FROM_PORT(&up->port); up->flags |= SUNZILOG_FLAG_ISR_HANDLER; up->curregs[R9] |= MIE; write_zsreg(channel, R9, up->curregs[R9]); up = up->next; } } out: return err; out_unregister_driver: platform_driver_unregister(&zs_driver); out_unregister_uart: if (num_sunzilog) { sunserial_unregister_minors(&sunzilog_reg, num_sunzilog); sunzilog_reg.cons = NULL; } out_free_tables: sunzilog_free_tables(); goto out; } static void __exit sunzilog_exit(void) { platform_driver_unregister(&zs_driver); if (zilog_irq) { struct uart_sunzilog_port *up = sunzilog_irq_chain; /* Disable Interrupts */ while (up) { struct zilog_channel __iomem *channel; /* printk (KERN_INFO "Disable IRQ for ZILOG Hardware %p\n", up); */ channel = ZILOG_CHANNEL_FROM_PORT(&up->port); up->flags &= ~SUNZILOG_FLAG_ISR_HANDLER; up->curregs[R9] &= ~MIE; write_zsreg(channel, R9, up->curregs[R9]); up = up->next; } free_irq(zilog_irq, sunzilog_irq_chain); zilog_irq = 0; } if (sunzilog_reg.nr) { sunserial_unregister_minors(&sunzilog_reg, sunzilog_reg.nr); sunzilog_free_tables(); } } module_init(sunzilog_init); module_exit(sunzilog_exit); MODULE_AUTHOR("David S. Miller"); MODULE_DESCRIPTION("Sun Zilog serial port driver"); MODULE_VERSION("2.0"); MODULE_LICENSE("GPL");