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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /drivers/tty/serial/sunsab.c | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/tty/serial/sunsab.c')
-rw-r--r-- | drivers/tty/serial/sunsab.c | 1165 |
1 files changed, 1165 insertions, 0 deletions
diff --git a/drivers/tty/serial/sunsab.c b/drivers/tty/serial/sunsab.c new file mode 100644 index 000000000..451c72336 --- /dev/null +++ b/drivers/tty/serial/sunsab.c @@ -0,0 +1,1165 @@ +// SPDX-License-Identifier: GPL-2.0 +/* sunsab.c: ASYNC Driver for the SIEMENS SAB82532 DUSCC. + * + * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be) + * Copyright (C) 2002, 2006 David S. Miller (davem@davemloft.net) + * + * Rewrote buffer handling to use CIRC(Circular Buffer) macros. + * Maxim Krasnyanskiy <maxk@qualcomm.com> + * + * Fixed to use tty_get_baud_rate, and to allow for arbitrary baud + * rates to be programmed into the UART. Also eliminated a lot of + * duplicated code in the console setup. + * Theodore Ts'o <tytso@mit.edu>, 2001-Oct-12 + * + * Ported to new 2.5.x UART layer. + * David S. Miller <davem@davemloft.net> + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/errno.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/circ_buf.h> +#include <linux/serial.h> +#include <linux/sysrq.h> +#include <linux/console.h> +#include <linux/spinlock.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/of_device.h> + +#include <asm/io.h> +#include <asm/irq.h> +#include <asm/prom.h> +#include <asm/setup.h> + +#include <linux/serial_core.h> +#include <linux/sunserialcore.h> + +#include "sunsab.h" + +struct uart_sunsab_port { + struct uart_port port; /* Generic UART port */ + union sab82532_async_regs __iomem *regs; /* Chip registers */ + unsigned long irqflags; /* IRQ state flags */ + int dsr; /* Current DSR state */ + unsigned int cec_timeout; /* Chip poll timeout... */ + unsigned int tec_timeout; /* likewise */ + unsigned char interrupt_mask0;/* ISR0 masking */ + unsigned char interrupt_mask1;/* ISR1 masking */ + unsigned char pvr_dtr_bit; /* Which PVR bit is DTR */ + unsigned char pvr_dsr_bit; /* Which PVR bit is DSR */ + unsigned int gis_shift; + int type; /* SAB82532 version */ + + /* Setting configuration bits while the transmitter is active + * can cause garbage characters to get emitted by the chip. + * Therefore, we cache such writes here and do the real register + * write the next time the transmitter becomes idle. + */ + unsigned int cached_ebrg; + unsigned char cached_mode; + unsigned char cached_pvr; + unsigned char cached_dafo; +}; + +/* + * This assumes you have a 29.4912 MHz clock for your UART. + */ +#define SAB_BASE_BAUD ( 29491200 / 16 ) + +static char *sab82532_version[16] = { + "V1.0", "V2.0", "V3.2", "V(0x03)", + "V(0x04)", "V(0x05)", "V(0x06)", "V(0x07)", + "V(0x08)", "V(0x09)", "V(0x0a)", "V(0x0b)", + "V(0x0c)", "V(0x0d)", "V(0x0e)", "V(0x0f)" +}; + +#define SAB82532_MAX_TEC_TIMEOUT 200000 /* 1 character time (at 50 baud) */ +#define SAB82532_MAX_CEC_TIMEOUT 50000 /* 2.5 TX CLKs (at 50 baud) */ + +#define SAB82532_RECV_FIFO_SIZE 32 /* Standard async fifo sizes */ +#define SAB82532_XMIT_FIFO_SIZE 32 + +static __inline__ void sunsab_tec_wait(struct uart_sunsab_port *up) +{ + int timeout = up->tec_timeout; + + while ((readb(&up->regs->r.star) & SAB82532_STAR_TEC) && --timeout) + udelay(1); +} + +static __inline__ void sunsab_cec_wait(struct uart_sunsab_port *up) +{ + int timeout = up->cec_timeout; + + while ((readb(&up->regs->r.star) & SAB82532_STAR_CEC) && --timeout) + udelay(1); +} + +static struct tty_port * +receive_chars(struct uart_sunsab_port *up, + union sab82532_irq_status *stat) +{ + struct tty_port *port = NULL; + unsigned char buf[32]; + int saw_console_brk = 0; + int free_fifo = 0; + int count = 0; + int i; + + if (up->port.state != NULL) /* Unopened serial console */ + port = &up->port.state->port; + + /* Read number of BYTES (Character + Status) available. */ + if (stat->sreg.isr0 & SAB82532_ISR0_RPF) { + count = SAB82532_RECV_FIFO_SIZE; + free_fifo++; + } + + if (stat->sreg.isr0 & SAB82532_ISR0_TCD) { + count = readb(&up->regs->r.rbcl) & (SAB82532_RECV_FIFO_SIZE - 1); + free_fifo++; + } + + /* Issue a FIFO read command in case we where idle. */ + if (stat->sreg.isr0 & SAB82532_ISR0_TIME) { + sunsab_cec_wait(up); + writeb(SAB82532_CMDR_RFRD, &up->regs->w.cmdr); + return port; + } + + if (stat->sreg.isr0 & SAB82532_ISR0_RFO) + free_fifo++; + + /* Read the FIFO. */ + for (i = 0; i < count; i++) + buf[i] = readb(&up->regs->r.rfifo[i]); + + /* Issue Receive Message Complete command. */ + if (free_fifo) { + sunsab_cec_wait(up); + writeb(SAB82532_CMDR_RMC, &up->regs->w.cmdr); + } + + /* Count may be zero for BRK, so we check for it here */ + if ((stat->sreg.isr1 & SAB82532_ISR1_BRK) && + (up->port.line == up->port.cons->index)) + saw_console_brk = 1; + + if (count == 0) { + if (unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) { + stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR | + SAB82532_ISR0_FERR); + up->port.icount.brk++; + uart_handle_break(&up->port); + } + } + + for (i = 0; i < count; i++) { + unsigned char ch = buf[i], flag; + + flag = TTY_NORMAL; + up->port.icount.rx++; + + if (unlikely(stat->sreg.isr0 & (SAB82532_ISR0_PERR | + SAB82532_ISR0_FERR | + SAB82532_ISR0_RFO)) || + unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) { + /* + * For statistics only + */ + if (stat->sreg.isr1 & SAB82532_ISR1_BRK) { + stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR | + SAB82532_ISR0_FERR); + up->port.icount.brk++; + /* + * We do the SysRQ and SAK checking + * here because otherwise the break + * may get masked by ignore_status_mask + * or read_status_mask. + */ + if (uart_handle_break(&up->port)) + continue; + } else if (stat->sreg.isr0 & SAB82532_ISR0_PERR) + up->port.icount.parity++; + else if (stat->sreg.isr0 & SAB82532_ISR0_FERR) + up->port.icount.frame++; + if (stat->sreg.isr0 & SAB82532_ISR0_RFO) + up->port.icount.overrun++; + + /* + * Mask off conditions which should be ingored. + */ + stat->sreg.isr0 &= (up->port.read_status_mask & 0xff); + stat->sreg.isr1 &= ((up->port.read_status_mask >> 8) & 0xff); + + if (stat->sreg.isr1 & SAB82532_ISR1_BRK) { + flag = TTY_BREAK; + } else if (stat->sreg.isr0 & SAB82532_ISR0_PERR) + flag = TTY_PARITY; + else if (stat->sreg.isr0 & SAB82532_ISR0_FERR) + flag = TTY_FRAME; + } + + if (uart_handle_sysrq_char(&up->port, ch) || !port) + continue; + + if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 && + (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0) + tty_insert_flip_char(port, ch, flag); + if (stat->sreg.isr0 & SAB82532_ISR0_RFO) + tty_insert_flip_char(port, 0, TTY_OVERRUN); + } + + if (saw_console_brk) + sun_do_break(); + + return port; +} + +static void sunsab_stop_tx(struct uart_port *); +static void sunsab_tx_idle(struct uart_sunsab_port *); + +static void transmit_chars(struct uart_sunsab_port *up, + union sab82532_irq_status *stat) +{ + struct circ_buf *xmit = &up->port.state->xmit; + int i; + + if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) { + up->interrupt_mask1 |= SAB82532_IMR1_ALLS; + writeb(up->interrupt_mask1, &up->regs->w.imr1); + set_bit(SAB82532_ALLS, &up->irqflags); + } + +#if 0 /* bde@nwlink.com says this check causes problems */ + if (!(stat->sreg.isr1 & SAB82532_ISR1_XPR)) + return; +#endif + + if (!(readb(&up->regs->r.star) & SAB82532_STAR_XFW)) + return; + + set_bit(SAB82532_XPR, &up->irqflags); + sunsab_tx_idle(up); + + if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) { + up->interrupt_mask1 |= SAB82532_IMR1_XPR; + writeb(up->interrupt_mask1, &up->regs->w.imr1); + return; + } + + up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR); + writeb(up->interrupt_mask1, &up->regs->w.imr1); + clear_bit(SAB82532_ALLS, &up->irqflags); + + /* Stuff 32 bytes into Transmit FIFO. */ + clear_bit(SAB82532_XPR, &up->irqflags); + for (i = 0; i < up->port.fifosize; i++) { + writeb(xmit->buf[xmit->tail], + &up->regs->w.xfifo[i]); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + up->port.icount.tx++; + if (uart_circ_empty(xmit)) + break; + } + + /* Issue a Transmit Frame command. */ + sunsab_cec_wait(up); + writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr); + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(&up->port); + + if (uart_circ_empty(xmit)) + sunsab_stop_tx(&up->port); +} + +static void check_status(struct uart_sunsab_port *up, + union sab82532_irq_status *stat) +{ + if (stat->sreg.isr0 & SAB82532_ISR0_CDSC) + uart_handle_dcd_change(&up->port, + !(readb(&up->regs->r.vstr) & SAB82532_VSTR_CD)); + + if (stat->sreg.isr1 & SAB82532_ISR1_CSC) + uart_handle_cts_change(&up->port, + (readb(&up->regs->r.star) & SAB82532_STAR_CTS)); + + if ((readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ^ up->dsr) { + up->dsr = (readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ? 0 : 1; + up->port.icount.dsr++; + } + + wake_up_interruptible(&up->port.state->port.delta_msr_wait); +} + +static irqreturn_t sunsab_interrupt(int irq, void *dev_id) +{ + struct uart_sunsab_port *up = dev_id; + struct tty_port *port = NULL; + union sab82532_irq_status status; + unsigned long flags; + unsigned char gis; + + spin_lock_irqsave(&up->port.lock, flags); + + status.stat = 0; + gis = readb(&up->regs->r.gis) >> up->gis_shift; + if (gis & 1) + status.sreg.isr0 = readb(&up->regs->r.isr0); + if (gis & 2) + status.sreg.isr1 = readb(&up->regs->r.isr1); + + if (status.stat) { + if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME | + SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) || + (status.sreg.isr1 & SAB82532_ISR1_BRK)) + port = receive_chars(up, &status); + if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) || + (status.sreg.isr1 & SAB82532_ISR1_CSC)) + check_status(up, &status); + if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR)) + transmit_chars(up, &status); + } + + spin_unlock_irqrestore(&up->port.lock, flags); + + if (port) + tty_flip_buffer_push(port); + + return IRQ_HANDLED; +} + +/* port->lock is not held. */ +static unsigned int sunsab_tx_empty(struct uart_port *port) +{ + struct uart_sunsab_port *up = + container_of(port, struct uart_sunsab_port, port); + int ret; + + /* Do not need a lock for a state test like this. */ + if (test_bit(SAB82532_ALLS, &up->irqflags)) + ret = TIOCSER_TEMT; + else + ret = 0; + + return ret; +} + +/* port->lock held by caller. */ +static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ + struct uart_sunsab_port *up = + container_of(port, struct uart_sunsab_port, port); + + if (mctrl & TIOCM_RTS) { + up->cached_mode &= ~SAB82532_MODE_FRTS; + up->cached_mode |= SAB82532_MODE_RTS; + } else { + up->cached_mode |= (SAB82532_MODE_FRTS | + SAB82532_MODE_RTS); + } + if (mctrl & TIOCM_DTR) { + up->cached_pvr &= ~(up->pvr_dtr_bit); + } else { + up->cached_pvr |= up->pvr_dtr_bit; + } + + set_bit(SAB82532_REGS_PENDING, &up->irqflags); + if (test_bit(SAB82532_XPR, &up->irqflags)) + sunsab_tx_idle(up); +} + +/* port->lock is held by caller and interrupts are disabled. */ +static unsigned int sunsab_get_mctrl(struct uart_port *port) +{ + struct uart_sunsab_port *up = + container_of(port, struct uart_sunsab_port, port); + unsigned char val; + unsigned int result; + + result = 0; + + val = readb(&up->regs->r.pvr); + result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR; + + val = readb(&up->regs->r.vstr); + result |= (val & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR; + + val = readb(&up->regs->r.star); + result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0; + + return result; +} + +/* port->lock held by caller. */ +static void sunsab_stop_tx(struct uart_port *port) +{ + struct uart_sunsab_port *up = + container_of(port, struct uart_sunsab_port, port); + + up->interrupt_mask1 |= SAB82532_IMR1_XPR; + writeb(up->interrupt_mask1, &up->regs->w.imr1); +} + +/* port->lock held by caller. */ +static void sunsab_tx_idle(struct uart_sunsab_port *up) +{ + if (test_bit(SAB82532_REGS_PENDING, &up->irqflags)) { + u8 tmp; + + clear_bit(SAB82532_REGS_PENDING, &up->irqflags); + writeb(up->cached_mode, &up->regs->rw.mode); + writeb(up->cached_pvr, &up->regs->rw.pvr); + writeb(up->cached_dafo, &up->regs->w.dafo); + + writeb(up->cached_ebrg & 0xff, &up->regs->w.bgr); + tmp = readb(&up->regs->rw.ccr2); + tmp &= ~0xc0; + tmp |= (up->cached_ebrg >> 2) & 0xc0; + writeb(tmp, &up->regs->rw.ccr2); + } +} + +/* port->lock held by caller. */ +static void sunsab_start_tx(struct uart_port *port) +{ + struct uart_sunsab_port *up = + container_of(port, struct uart_sunsab_port, port); + struct circ_buf *xmit = &up->port.state->xmit; + int i; + + if (uart_circ_empty(xmit) || uart_tx_stopped(port)) + return; + + up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR); + writeb(up->interrupt_mask1, &up->regs->w.imr1); + + if (!test_bit(SAB82532_XPR, &up->irqflags)) + return; + + clear_bit(SAB82532_ALLS, &up->irqflags); + clear_bit(SAB82532_XPR, &up->irqflags); + + for (i = 0; i < up->port.fifosize; i++) { + writeb(xmit->buf[xmit->tail], + &up->regs->w.xfifo[i]); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + up->port.icount.tx++; + if (uart_circ_empty(xmit)) + break; + } + + /* Issue a Transmit Frame command. */ + sunsab_cec_wait(up); + writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr); +} + +/* port->lock is not held. */ +static void sunsab_send_xchar(struct uart_port *port, char ch) +{ + struct uart_sunsab_port *up = + container_of(port, struct uart_sunsab_port, port); + unsigned long flags; + + if (ch == __DISABLED_CHAR) + return; + + spin_lock_irqsave(&up->port.lock, flags); + + sunsab_tec_wait(up); + writeb(ch, &up->regs->w.tic); + + spin_unlock_irqrestore(&up->port.lock, flags); +} + +/* port->lock held by caller. */ +static void sunsab_stop_rx(struct uart_port *port) +{ + struct uart_sunsab_port *up = + container_of(port, struct uart_sunsab_port, port); + + up->interrupt_mask0 |= SAB82532_IMR0_TCD; + writeb(up->interrupt_mask1, &up->regs->w.imr0); +} + +/* port->lock is not held. */ +static void sunsab_break_ctl(struct uart_port *port, int break_state) +{ + struct uart_sunsab_port *up = + container_of(port, struct uart_sunsab_port, port); + unsigned long flags; + unsigned char val; + + spin_lock_irqsave(&up->port.lock, flags); + + val = up->cached_dafo; + if (break_state) + val |= SAB82532_DAFO_XBRK; + else + val &= ~SAB82532_DAFO_XBRK; + up->cached_dafo = val; + + set_bit(SAB82532_REGS_PENDING, &up->irqflags); + if (test_bit(SAB82532_XPR, &up->irqflags)) + sunsab_tx_idle(up); + + spin_unlock_irqrestore(&up->port.lock, flags); +} + +/* port->lock is not held. */ +static int sunsab_startup(struct uart_port *port) +{ + struct uart_sunsab_port *up = + container_of(port, struct uart_sunsab_port, port); + unsigned long flags; + unsigned char tmp; + int err = request_irq(up->port.irq, sunsab_interrupt, + IRQF_SHARED, "sab", up); + if (err) + return err; + + spin_lock_irqsave(&up->port.lock, flags); + + /* + * Wait for any commands or immediate characters + */ + sunsab_cec_wait(up); + sunsab_tec_wait(up); + + /* + * Clear the FIFO buffers. + */ + writeb(SAB82532_CMDR_RRES, &up->regs->w.cmdr); + sunsab_cec_wait(up); + writeb(SAB82532_CMDR_XRES, &up->regs->w.cmdr); + + /* + * Clear the interrupt registers. + */ + (void) readb(&up->regs->r.isr0); + (void) readb(&up->regs->r.isr1); + + /* + * Now, initialize the UART + */ + writeb(0, &up->regs->w.ccr0); /* power-down */ + writeb(SAB82532_CCR0_MCE | SAB82532_CCR0_SC_NRZ | + SAB82532_CCR0_SM_ASYNC, &up->regs->w.ccr0); + writeb(SAB82532_CCR1_ODS | SAB82532_CCR1_BCR | 7, &up->regs->w.ccr1); + writeb(SAB82532_CCR2_BDF | SAB82532_CCR2_SSEL | + SAB82532_CCR2_TOE, &up->regs->w.ccr2); + writeb(0, &up->regs->w.ccr3); + writeb(SAB82532_CCR4_MCK4 | SAB82532_CCR4_EBRG, &up->regs->w.ccr4); + up->cached_mode = (SAB82532_MODE_RTS | SAB82532_MODE_FCTS | + SAB82532_MODE_RAC); + writeb(up->cached_mode, &up->regs->w.mode); + writeb(SAB82532_RFC_DPS|SAB82532_RFC_RFTH_32, &up->regs->w.rfc); + + tmp = readb(&up->regs->rw.ccr0); + tmp |= SAB82532_CCR0_PU; /* power-up */ + writeb(tmp, &up->regs->rw.ccr0); + + /* + * Finally, enable interrupts + */ + up->interrupt_mask0 = (SAB82532_IMR0_PERR | SAB82532_IMR0_FERR | + SAB82532_IMR0_PLLA); + writeb(up->interrupt_mask0, &up->regs->w.imr0); + up->interrupt_mask1 = (SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS | + SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN | + SAB82532_IMR1_CSC | SAB82532_IMR1_XON | + SAB82532_IMR1_XPR); + writeb(up->interrupt_mask1, &up->regs->w.imr1); + set_bit(SAB82532_ALLS, &up->irqflags); + set_bit(SAB82532_XPR, &up->irqflags); + + spin_unlock_irqrestore(&up->port.lock, flags); + + return 0; +} + +/* port->lock is not held. */ +static void sunsab_shutdown(struct uart_port *port) +{ + struct uart_sunsab_port *up = + container_of(port, struct uart_sunsab_port, port); + unsigned long flags; + + spin_lock_irqsave(&up->port.lock, flags); + + /* Disable Interrupts */ + up->interrupt_mask0 = 0xff; + writeb(up->interrupt_mask0, &up->regs->w.imr0); + up->interrupt_mask1 = 0xff; + writeb(up->interrupt_mask1, &up->regs->w.imr1); + + /* Disable break condition */ + up->cached_dafo = readb(&up->regs->rw.dafo); + up->cached_dafo &= ~SAB82532_DAFO_XBRK; + writeb(up->cached_dafo, &up->regs->rw.dafo); + + /* Disable Receiver */ + up->cached_mode &= ~SAB82532_MODE_RAC; + writeb(up->cached_mode, &up->regs->rw.mode); + + /* + * XXX FIXME + * + * If the chip is powered down here the system hangs/crashes during + * reboot or shutdown. This needs to be investigated further, + * similar behaviour occurs in 2.4 when the driver is configured + * as a module only. One hint may be that data is sometimes + * transmitted at 9600 baud during shutdown (regardless of the + * speed the chip was configured for when the port was open). + */ +#if 0 + /* Power Down */ + tmp = readb(&up->regs->rw.ccr0); + tmp &= ~SAB82532_CCR0_PU; + writeb(tmp, &up->regs->rw.ccr0); +#endif + + spin_unlock_irqrestore(&up->port.lock, flags); + free_irq(up->port.irq, up); +} + +/* + * This is used to figure out the divisor speeds. + * + * The formula is: Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)), + * + * with 0 <= N < 64 and 0 <= M < 16 + */ + +static void calc_ebrg(int baud, int *n_ret, int *m_ret) +{ + int n, m; + + if (baud == 0) { + *n_ret = 0; + *m_ret = 0; + return; + } + + /* + * We scale numbers by 10 so that we get better accuracy + * without having to use floating point. Here we increment m + * until n is within the valid range. + */ + n = (SAB_BASE_BAUD * 10) / baud; + m = 0; + while (n >= 640) { + n = n / 2; + m++; + } + n = (n+5) / 10; + /* + * We try very hard to avoid speeds with M == 0 since they may + * not work correctly for XTAL frequences above 10 MHz. + */ + if ((m == 0) && ((n & 1) == 0)) { + n = n / 2; + m++; + } + *n_ret = n - 1; + *m_ret = m; +} + +/* Internal routine, port->lock is held and local interrupts are disabled. */ +static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag, + unsigned int iflag, unsigned int baud, + unsigned int quot) +{ + unsigned char dafo; + int bits, n, m; + + /* Byte size and parity */ + switch (cflag & CSIZE) { + case CS5: dafo = SAB82532_DAFO_CHL5; bits = 7; break; + case CS6: dafo = SAB82532_DAFO_CHL6; bits = 8; break; + case CS7: dafo = SAB82532_DAFO_CHL7; bits = 9; break; + case CS8: dafo = SAB82532_DAFO_CHL8; bits = 10; break; + /* Never happens, but GCC is too dumb to figure it out */ + default: dafo = SAB82532_DAFO_CHL5; bits = 7; break; + } + + if (cflag & CSTOPB) { + dafo |= SAB82532_DAFO_STOP; + bits++; + } + + if (cflag & PARENB) { + dafo |= SAB82532_DAFO_PARE; + bits++; + } + + if (cflag & PARODD) { + dafo |= SAB82532_DAFO_PAR_ODD; + } else { + dafo |= SAB82532_DAFO_PAR_EVEN; + } + up->cached_dafo = dafo; + + calc_ebrg(baud, &n, &m); + + up->cached_ebrg = n | (m << 6); + + up->tec_timeout = (10 * 1000000) / baud; + up->cec_timeout = up->tec_timeout >> 2; + + /* CTS flow control flags */ + /* We encode read_status_mask and ignore_status_mask like so: + * + * --------------------- + * | ... | ISR1 | ISR0 | + * --------------------- + * .. 15 8 7 0 + */ + + up->port.read_status_mask = (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME | + SAB82532_ISR0_RFO | SAB82532_ISR0_RPF | + SAB82532_ISR0_CDSC); + up->port.read_status_mask |= (SAB82532_ISR1_CSC | + SAB82532_ISR1_ALLS | + SAB82532_ISR1_XPR) << 8; + if (iflag & INPCK) + up->port.read_status_mask |= (SAB82532_ISR0_PERR | + SAB82532_ISR0_FERR); + if (iflag & (IGNBRK | BRKINT | PARMRK)) + up->port.read_status_mask |= (SAB82532_ISR1_BRK << 8); + + /* + * Characteres to ignore + */ + up->port.ignore_status_mask = 0; + if (iflag & IGNPAR) + up->port.ignore_status_mask |= (SAB82532_ISR0_PERR | + SAB82532_ISR0_FERR); + if (iflag & IGNBRK) { + up->port.ignore_status_mask |= (SAB82532_ISR1_BRK << 8); + /* + * If we're ignoring parity and break indicators, + * ignore overruns too (for real raw support). + */ + if (iflag & IGNPAR) + up->port.ignore_status_mask |= SAB82532_ISR0_RFO; + } + + /* + * ignore all characters if CREAD is not set + */ + if ((cflag & CREAD) == 0) + up->port.ignore_status_mask |= (SAB82532_ISR0_RPF | + SAB82532_ISR0_TCD); + + uart_update_timeout(&up->port, cflag, + (up->port.uartclk / (16 * quot))); + + /* Now schedule a register update when the chip's + * transmitter is idle. + */ + up->cached_mode |= SAB82532_MODE_RAC; + set_bit(SAB82532_REGS_PENDING, &up->irqflags); + if (test_bit(SAB82532_XPR, &up->irqflags)) + sunsab_tx_idle(up); +} + +/* port->lock is not held. */ +static void sunsab_set_termios(struct uart_port *port, struct ktermios *termios, + struct ktermios *old) +{ + struct uart_sunsab_port *up = + container_of(port, struct uart_sunsab_port, port); + unsigned long flags; + unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000); + unsigned int quot = uart_get_divisor(port, baud); + + spin_lock_irqsave(&up->port.lock, flags); + sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud, quot); + spin_unlock_irqrestore(&up->port.lock, flags); +} + +static const char *sunsab_type(struct uart_port *port) +{ + struct uart_sunsab_port *up = (void *)port; + static char buf[36]; + + sprintf(buf, "SAB82532 %s", sab82532_version[up->type]); + return buf; +} + +static void sunsab_release_port(struct uart_port *port) +{ +} + +static int sunsab_request_port(struct uart_port *port) +{ + return 0; +} + +static void sunsab_config_port(struct uart_port *port, int flags) +{ +} + +static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser) +{ + return -EINVAL; +} + +static const struct uart_ops sunsab_pops = { + .tx_empty = sunsab_tx_empty, + .set_mctrl = sunsab_set_mctrl, + .get_mctrl = sunsab_get_mctrl, + .stop_tx = sunsab_stop_tx, + .start_tx = sunsab_start_tx, + .send_xchar = sunsab_send_xchar, + .stop_rx = sunsab_stop_rx, + .break_ctl = sunsab_break_ctl, + .startup = sunsab_startup, + .shutdown = sunsab_shutdown, + .set_termios = sunsab_set_termios, + .type = sunsab_type, + .release_port = sunsab_release_port, + .request_port = sunsab_request_port, + .config_port = sunsab_config_port, + .verify_port = sunsab_verify_port, +}; + +static struct uart_driver sunsab_reg = { + .owner = THIS_MODULE, + .driver_name = "sunsab", + .dev_name = "ttyS", + .major = TTY_MAJOR, +}; + +static struct uart_sunsab_port *sunsab_ports; + +#ifdef CONFIG_SERIAL_SUNSAB_CONSOLE + +static void sunsab_console_putchar(struct uart_port *port, int c) +{ + struct uart_sunsab_port *up = + container_of(port, struct uart_sunsab_port, port); + + sunsab_tec_wait(up); + writeb(c, &up->regs->w.tic); +} + +static void sunsab_console_write(struct console *con, const char *s, unsigned n) +{ + struct uart_sunsab_port *up = &sunsab_ports[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, n, sunsab_console_putchar); + sunsab_tec_wait(up); + + if (locked) + spin_unlock_irqrestore(&up->port.lock, flags); +} + +static int sunsab_console_setup(struct console *con, char *options) +{ + struct uart_sunsab_port *up = &sunsab_ports[con->index]; + unsigned long flags; + unsigned int baud, quot; + + /* + * The console framework calls us for each and every port + * registered. Defer the console setup until the requested + * port has been properly discovered. A bit of a hack, + * though... + */ + if (up->port.type != PORT_SUNSAB) + return -EINVAL; + + printk("Console: ttyS%d (SAB82532)\n", + (sunsab_reg.minor - 64) + con->index); + + sunserial_console_termios(con, up->port.dev->of_node); + + 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; + case B57600: baud = 57600; break; + case B115200: baud = 115200; break; + case B230400: baud = 230400; break; + case B460800: baud = 460800; break; + } + + /* + * Temporary fix. + */ + spin_lock_init(&up->port.lock); + + /* + * Initialize the hardware + */ + sunsab_startup(&up->port); + + spin_lock_irqsave(&up->port.lock, flags); + + /* + * Finally, enable interrupts + */ + up->interrupt_mask0 = SAB82532_IMR0_PERR | SAB82532_IMR0_FERR | + SAB82532_IMR0_PLLA | SAB82532_IMR0_CDSC; + writeb(up->interrupt_mask0, &up->regs->w.imr0); + up->interrupt_mask1 = SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS | + SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN | + SAB82532_IMR1_CSC | SAB82532_IMR1_XON | + SAB82532_IMR1_XPR; + writeb(up->interrupt_mask1, &up->regs->w.imr1); + + quot = uart_get_divisor(&up->port, baud); + sunsab_convert_to_sab(up, con->cflag, 0, baud, quot); + sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS); + + spin_unlock_irqrestore(&up->port.lock, flags); + + return 0; +} + +static struct console sunsab_console = { + .name = "ttyS", + .write = sunsab_console_write, + .device = uart_console_device, + .setup = sunsab_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &sunsab_reg, +}; + +static inline struct console *SUNSAB_CONSOLE(void) +{ + return &sunsab_console; +} +#else +#define SUNSAB_CONSOLE() (NULL) +#define sunsab_console_init() do { } while (0) +#endif + +static int sunsab_init_one(struct uart_sunsab_port *up, + struct platform_device *op, + unsigned long offset, + int line) +{ + up->port.line = line; + up->port.dev = &op->dev; + + up->port.mapbase = op->resource[0].start + offset; + up->port.membase = of_ioremap(&op->resource[0], offset, + sizeof(union sab82532_async_regs), + "sab"); + if (!up->port.membase) + return -ENOMEM; + up->regs = (union sab82532_async_regs __iomem *) up->port.membase; + + up->port.irq = op->archdata.irqs[0]; + + up->port.fifosize = SAB82532_XMIT_FIFO_SIZE; + up->port.iotype = UPIO_MEM; + up->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SUNSAB_CONSOLE); + + writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc); + + up->port.ops = &sunsab_pops; + up->port.type = PORT_SUNSAB; + up->port.uartclk = SAB_BASE_BAUD; + + up->type = readb(&up->regs->r.vstr) & 0x0f; + writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr); + writeb(0xff, &up->regs->w.pim); + if ((up->port.line & 0x1) == 0) { + up->pvr_dsr_bit = (1 << 0); + up->pvr_dtr_bit = (1 << 1); + up->gis_shift = 2; + } else { + up->pvr_dsr_bit = (1 << 3); + up->pvr_dtr_bit = (1 << 2); + up->gis_shift = 0; + } + up->cached_pvr = (1 << 1) | (1 << 2) | (1 << 4); + writeb(up->cached_pvr, &up->regs->w.pvr); + up->cached_mode = readb(&up->regs->rw.mode); + up->cached_mode |= SAB82532_MODE_FRTS; + writeb(up->cached_mode, &up->regs->rw.mode); + up->cached_mode |= SAB82532_MODE_RTS; + writeb(up->cached_mode, &up->regs->rw.mode); + + up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT; + up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT; + + return 0; +} + +static int sab_probe(struct platform_device *op) +{ + static int inst; + struct uart_sunsab_port *up; + int err; + + up = &sunsab_ports[inst * 2]; + + err = sunsab_init_one(&up[0], op, + 0, + (inst * 2) + 0); + if (err) + goto out; + + err = sunsab_init_one(&up[1], op, + sizeof(union sab82532_async_regs), + (inst * 2) + 1); + if (err) + goto out1; + + sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node, + &sunsab_reg, up[0].port.line, + false); + + sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node, + &sunsab_reg, up[1].port.line, + false); + + err = uart_add_one_port(&sunsab_reg, &up[0].port); + if (err) + goto out2; + + err = uart_add_one_port(&sunsab_reg, &up[1].port); + if (err) + goto out3; + + platform_set_drvdata(op, &up[0]); + + inst++; + + return 0; + +out3: + uart_remove_one_port(&sunsab_reg, &up[0].port); +out2: + of_iounmap(&op->resource[0], + up[1].port.membase, + sizeof(union sab82532_async_regs)); +out1: + of_iounmap(&op->resource[0], + up[0].port.membase, + sizeof(union sab82532_async_regs)); +out: + return err; +} + +static int sab_remove(struct platform_device *op) +{ + struct uart_sunsab_port *up = platform_get_drvdata(op); + + uart_remove_one_port(&sunsab_reg, &up[1].port); + uart_remove_one_port(&sunsab_reg, &up[0].port); + of_iounmap(&op->resource[0], + up[1].port.membase, + sizeof(union sab82532_async_regs)); + of_iounmap(&op->resource[0], + up[0].port.membase, + sizeof(union sab82532_async_regs)); + + return 0; +} + +static const struct of_device_id sab_match[] = { + { + .name = "se", + }, + { + .name = "serial", + .compatible = "sab82532", + }, + {}, +}; +MODULE_DEVICE_TABLE(of, sab_match); + +static struct platform_driver sab_driver = { + .driver = { + .name = "sab", + .of_match_table = sab_match, + }, + .probe = sab_probe, + .remove = sab_remove, +}; + +static int __init sunsab_init(void) +{ + struct device_node *dp; + int err; + int num_channels = 0; + + for_each_node_by_name(dp, "se") + num_channels += 2; + for_each_node_by_name(dp, "serial") { + if (of_device_is_compatible(dp, "sab82532")) + num_channels += 2; + } + + if (num_channels) { + sunsab_ports = kcalloc(num_channels, + sizeof(struct uart_sunsab_port), + GFP_KERNEL); + if (!sunsab_ports) + return -ENOMEM; + + err = sunserial_register_minors(&sunsab_reg, num_channels); + if (err) { + kfree(sunsab_ports); + sunsab_ports = NULL; + + return err; + } + } + + err = platform_driver_register(&sab_driver); + if (err) { + kfree(sunsab_ports); + sunsab_ports = NULL; + } + + return err; +} + +static void __exit sunsab_exit(void) +{ + platform_driver_unregister(&sab_driver); + if (sunsab_reg.nr) { + sunserial_unregister_minors(&sunsab_reg, sunsab_reg.nr); + } + + kfree(sunsab_ports); + sunsab_ports = NULL; +} + +module_init(sunsab_init); +module_exit(sunsab_exit); + +MODULE_AUTHOR("Eddie C. Dost and David S. Miller"); +MODULE_DESCRIPTION("Sun SAB82532 serial port driver"); +MODULE_LICENSE("GPL"); |