// SPDX-License-Identifier: GPL-2.0+ /* * Driver for CPM (SCC/SMC) serial ports; core driver * * Based on arch/ppc/cpm2_io/uart.c by Dan Malek * Based on ppc8xx.c by Thomas Gleixner * Based on drivers/serial/amba.c by Russell King * * Maintainer: Kumar Gala (galak@kernel.crashing.org) (CPM2) * Pantelis Antoniou (panto@intracom.gr) (CPM1) * * Copyright (C) 2004, 2007 Freescale Semiconductor, Inc. * (C) 2004 Intracom, S.A. * (C) 2005-2006 MontaVista Software, Inc. * Vitaly Bordug */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "cpm_uart.h" /**************************************************************/ static int cpm_uart_tx_pump(struct uart_port *port); static void cpm_uart_initbd(struct uart_cpm_port *pinfo); /**************************************************************/ #define HW_BUF_SPD_THRESHOLD 2400 static void cpm_line_cr_cmd(struct uart_cpm_port *port, int cmd) { cpm_command(port->command, cmd); } /* * Check, if transmit buffers are processed */ static unsigned int cpm_uart_tx_empty(struct uart_port *port) { struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); cbd_t __iomem *bdp = pinfo->tx_bd_base; int ret = 0; while (1) { if (in_be16(&bdp->cbd_sc) & BD_SC_READY) break; if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP) { ret = TIOCSER_TEMT; break; } bdp++; } pr_debug("CPM uart[%d]:tx_empty: %d\n", port->line, ret); return ret; } static void cpm_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) { struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); if (pinfo->gpios[GPIO_RTS]) gpiod_set_value(pinfo->gpios[GPIO_RTS], !(mctrl & TIOCM_RTS)); if (pinfo->gpios[GPIO_DTR]) gpiod_set_value(pinfo->gpios[GPIO_DTR], !(mctrl & TIOCM_DTR)); } static unsigned int cpm_uart_get_mctrl(struct uart_port *port) { struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); unsigned int mctrl = TIOCM_CTS | TIOCM_DSR | TIOCM_CAR; if (pinfo->gpios[GPIO_CTS]) { if (gpiod_get_value(pinfo->gpios[GPIO_CTS])) mctrl &= ~TIOCM_CTS; } if (pinfo->gpios[GPIO_DSR]) { if (gpiod_get_value(pinfo->gpios[GPIO_DSR])) mctrl &= ~TIOCM_DSR; } if (pinfo->gpios[GPIO_DCD]) { if (gpiod_get_value(pinfo->gpios[GPIO_DCD])) mctrl &= ~TIOCM_CAR; } if (pinfo->gpios[GPIO_RI]) { if (!gpiod_get_value(pinfo->gpios[GPIO_RI])) mctrl |= TIOCM_RNG; } return mctrl; } /* * Stop transmitter */ static void cpm_uart_stop_tx(struct uart_port *port) { struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); smc_t __iomem *smcp = pinfo->smcp; scc_t __iomem *sccp = pinfo->sccp; pr_debug("CPM uart[%d]:stop tx\n", port->line); if (IS_SMC(pinfo)) clrbits8(&smcp->smc_smcm, SMCM_TX); else clrbits16(&sccp->scc_sccm, UART_SCCM_TX); } /* * Start transmitter */ static void cpm_uart_start_tx(struct uart_port *port) { struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); smc_t __iomem *smcp = pinfo->smcp; scc_t __iomem *sccp = pinfo->sccp; pr_debug("CPM uart[%d]:start tx\n", port->line); if (IS_SMC(pinfo)) { if (in_8(&smcp->smc_smcm) & SMCM_TX) return; } else { if (in_be16(&sccp->scc_sccm) & UART_SCCM_TX) return; } if (cpm_uart_tx_pump(port) != 0) { if (IS_SMC(pinfo)) { setbits8(&smcp->smc_smcm, SMCM_TX); } else { setbits16(&sccp->scc_sccm, UART_SCCM_TX); } } } /* * Stop receiver */ static void cpm_uart_stop_rx(struct uart_port *port) { struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); smc_t __iomem *smcp = pinfo->smcp; scc_t __iomem *sccp = pinfo->sccp; pr_debug("CPM uart[%d]:stop rx\n", port->line); if (IS_SMC(pinfo)) clrbits8(&smcp->smc_smcm, SMCM_RX); else clrbits16(&sccp->scc_sccm, UART_SCCM_RX); } /* * Generate a break. */ static void cpm_uart_break_ctl(struct uart_port *port, int break_state) { struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); pr_debug("CPM uart[%d]:break ctrl, break_state: %d\n", port->line, break_state); if (break_state) cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX); else cpm_line_cr_cmd(pinfo, CPM_CR_RESTART_TX); } /* * Transmit characters, refill buffer descriptor, if possible */ static void cpm_uart_int_tx(struct uart_port *port) { pr_debug("CPM uart[%d]:TX INT\n", port->line); cpm_uart_tx_pump(port); } #ifdef CONFIG_CONSOLE_POLL static int serial_polled; #endif /* * Receive characters */ static void cpm_uart_int_rx(struct uart_port *port) { int i; unsigned char ch; u8 *cp; struct tty_port *tport = &port->state->port; struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); cbd_t __iomem *bdp; u16 status; unsigned int flg; pr_debug("CPM uart[%d]:RX INT\n", port->line); /* Just loop through the closed BDs and copy the characters into * the buffer. */ bdp = pinfo->rx_cur; for (;;) { #ifdef CONFIG_CONSOLE_POLL if (unlikely(serial_polled)) { serial_polled = 0; return; } #endif /* get status */ status = in_be16(&bdp->cbd_sc); /* If this one is empty, return happy */ if (status & BD_SC_EMPTY) break; /* get number of characters, and check spce in flip-buffer */ i = in_be16(&bdp->cbd_datlen); /* If we have not enough room in tty flip buffer, then we try * later, which will be the next rx-interrupt or a timeout */ if (tty_buffer_request_room(tport, i) < i) { printk(KERN_WARNING "No room in flip buffer\n"); return; } /* get pointer */ cp = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo); /* loop through the buffer */ while (i-- > 0) { ch = *cp++; port->icount.rx++; flg = TTY_NORMAL; if (status & (BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV)) goto handle_error; if (uart_handle_sysrq_char(port, ch)) continue; #ifdef CONFIG_CONSOLE_POLL if (unlikely(serial_polled)) { serial_polled = 0; return; } #endif error_return: tty_insert_flip_char(tport, ch, flg); } /* End while (i--) */ /* This BD is ready to be used again. Clear status. get next */ clrbits16(&bdp->cbd_sc, BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV | BD_SC_ID); setbits16(&bdp->cbd_sc, BD_SC_EMPTY); if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP) bdp = pinfo->rx_bd_base; else bdp++; } /* End for (;;) */ /* Write back buffer pointer */ pinfo->rx_cur = bdp; /* activate BH processing */ tty_flip_buffer_push(tport); return; /* Error processing */ handle_error: /* Statistics */ if (status & BD_SC_BR) port->icount.brk++; if (status & BD_SC_PR) port->icount.parity++; if (status & BD_SC_FR) port->icount.frame++; if (status & BD_SC_OV) port->icount.overrun++; /* Mask out ignored conditions */ status &= port->read_status_mask; /* Handle the remaining ones */ if (status & BD_SC_BR) flg = TTY_BREAK; else if (status & BD_SC_PR) flg = TTY_PARITY; else if (status & BD_SC_FR) flg = TTY_FRAME; /* overrun does not affect the current character ! */ if (status & BD_SC_OV) { ch = 0; flg = TTY_OVERRUN; /* We skip this buffer */ /* CHECK: Is really nothing senseful there */ /* ASSUMPTION: it contains nothing valid */ i = 0; } port->sysrq = 0; goto error_return; } /* * Asynchron mode interrupt handler */ static irqreturn_t cpm_uart_int(int irq, void *data) { u8 events; struct uart_port *port = data; struct uart_cpm_port *pinfo = (struct uart_cpm_port *)port; smc_t __iomem *smcp = pinfo->smcp; scc_t __iomem *sccp = pinfo->sccp; pr_debug("CPM uart[%d]:IRQ\n", port->line); if (IS_SMC(pinfo)) { events = in_8(&smcp->smc_smce); out_8(&smcp->smc_smce, events); if (events & SMCM_BRKE) uart_handle_break(port); if (events & SMCM_RX) cpm_uart_int_rx(port); if (events & SMCM_TX) cpm_uart_int_tx(port); } else { events = in_be16(&sccp->scc_scce); out_be16(&sccp->scc_scce, events); if (events & UART_SCCM_BRKE) uart_handle_break(port); if (events & UART_SCCM_RX) cpm_uart_int_rx(port); if (events & UART_SCCM_TX) cpm_uart_int_tx(port); } return (events) ? IRQ_HANDLED : IRQ_NONE; } static int cpm_uart_startup(struct uart_port *port) { int retval; struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); pr_debug("CPM uart[%d]:startup\n", port->line); /* If the port is not the console, make sure rx is disabled. */ if (!(pinfo->flags & FLAG_CONSOLE)) { /* Disable UART rx */ if (IS_SMC(pinfo)) { clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN); clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX); } else { clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR); clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_RX); } cpm_uart_initbd(pinfo); if (IS_SMC(pinfo)) { out_be32(&pinfo->smcup->smc_rstate, 0); out_be32(&pinfo->smcup->smc_tstate, 0); out_be16(&pinfo->smcup->smc_rbptr, in_be16(&pinfo->smcup->smc_rbase)); out_be16(&pinfo->smcup->smc_tbptr, in_be16(&pinfo->smcup->smc_tbase)); } else { cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX); } } /* Install interrupt handler. */ retval = request_irq(port->irq, cpm_uart_int, 0, "cpm_uart", port); if (retval) return retval; /* Startup rx-int */ if (IS_SMC(pinfo)) { setbits8(&pinfo->smcp->smc_smcm, SMCM_RX); setbits16(&pinfo->smcp->smc_smcmr, (SMCMR_REN | SMCMR_TEN)); } else { setbits16(&pinfo->sccp->scc_sccm, UART_SCCM_RX); setbits32(&pinfo->sccp->scc_gsmrl, (SCC_GSMRL_ENR | SCC_GSMRL_ENT)); } return 0; } inline void cpm_uart_wait_until_send(struct uart_cpm_port *pinfo) { set_current_state(TASK_UNINTERRUPTIBLE); schedule_timeout(pinfo->wait_closing); } /* * Shutdown the uart */ static void cpm_uart_shutdown(struct uart_port *port) { struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); pr_debug("CPM uart[%d]:shutdown\n", port->line); /* free interrupt handler */ free_irq(port->irq, port); /* If the port is not the console, disable Rx and Tx. */ if (!(pinfo->flags & FLAG_CONSOLE)) { /* Wait for all the BDs marked sent */ while(!cpm_uart_tx_empty(port)) { set_current_state(TASK_UNINTERRUPTIBLE); schedule_timeout(2); } if (pinfo->wait_closing) cpm_uart_wait_until_send(pinfo); /* Stop uarts */ if (IS_SMC(pinfo)) { smc_t __iomem *smcp = pinfo->smcp; clrbits16(&smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN); clrbits8(&smcp->smc_smcm, SMCM_RX | SMCM_TX); } else { scc_t __iomem *sccp = pinfo->sccp; clrbits32(&sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT); clrbits16(&sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX); } /* Shut them really down and reinit buffer descriptors */ if (IS_SMC(pinfo)) { out_be16(&pinfo->smcup->smc_brkcr, 0); cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX); } else { out_be16(&pinfo->sccup->scc_brkcr, 0); cpm_line_cr_cmd(pinfo, CPM_CR_GRA_STOP_TX); } cpm_uart_initbd(pinfo); } } static void cpm_uart_set_termios(struct uart_port *port, struct ktermios *termios, const struct ktermios *old) { int baud; unsigned long flags; u16 cval, scval, prev_mode; struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); smc_t __iomem *smcp = pinfo->smcp; scc_t __iomem *sccp = pinfo->sccp; int maxidl; pr_debug("CPM uart[%d]:set_termios\n", port->line); baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16); if (baud < HW_BUF_SPD_THRESHOLD || port->flags & UPF_LOW_LATENCY) pinfo->rx_fifosize = 1; else pinfo->rx_fifosize = RX_BUF_SIZE; /* MAXIDL is the timeout after which a receive buffer is closed * when not full if no more characters are received. * We calculate it from the baudrate so that the duration is * always the same at standard rates: about 4ms. */ maxidl = baud / 2400; if (maxidl < 1) maxidl = 1; if (maxidl > 0x10) maxidl = 0x10; cval = 0; scval = 0; if (termios->c_cflag & CSTOPB) { cval |= SMCMR_SL; /* Two stops */ scval |= SCU_PSMR_SL; } if (termios->c_cflag & PARENB) { cval |= SMCMR_PEN; scval |= SCU_PSMR_PEN; if (!(termios->c_cflag & PARODD)) { cval |= SMCMR_PM_EVEN; scval |= (SCU_PSMR_REVP | SCU_PSMR_TEVP); } } /* * Update the timeout */ uart_update_timeout(port, termios->c_cflag, baud); /* * Set up parity check flag */ port->read_status_mask = (BD_SC_EMPTY | BD_SC_OV); if (termios->c_iflag & INPCK) port->read_status_mask |= BD_SC_FR | BD_SC_PR; if ((termios->c_iflag & BRKINT) || (termios->c_iflag & PARMRK)) port->read_status_mask |= BD_SC_BR; /* * Characters to ignore */ port->ignore_status_mask = 0; if (termios->c_iflag & IGNPAR) port->ignore_status_mask |= BD_SC_PR | BD_SC_FR; if (termios->c_iflag & IGNBRK) { port->ignore_status_mask |= BD_SC_BR; /* * If we're ignore parity and break indicators, ignore * overruns too. (For real raw support). */ if (termios->c_iflag & IGNPAR) port->ignore_status_mask |= BD_SC_OV; } /* * !!! ignore all characters if CREAD is not set */ if ((termios->c_cflag & CREAD) == 0) port->read_status_mask &= ~BD_SC_EMPTY; uart_port_lock_irqsave(port, &flags); if (IS_SMC(pinfo)) { unsigned int bits = tty_get_frame_size(termios->c_cflag); /* * MRBLR can be changed while an SMC/SCC is operating only * if it is done in a single bus cycle with one 16-bit move * (not two 8-bit bus cycles back-to-back). This occurs when * the cp shifts control to the next RxBD, so the change does * not take effect immediately. To guarantee the exact RxBD * on which the change occurs, change MRBLR only while the * SMC/SCC receiver is disabled. */ out_be16(&pinfo->smcup->smc_mrblr, pinfo->rx_fifosize); out_be16(&pinfo->smcup->smc_maxidl, maxidl); /* Set the mode register. We want to keep a copy of the * enables, because we want to put them back if they were * present. */ prev_mode = in_be16(&smcp->smc_smcmr) & (SMCMR_REN | SMCMR_TEN); /* Output in *one* operation, so we don't interrupt RX/TX if they * were already enabled. * Character length programmed into the register is frame bits minus 1. */ out_be16(&smcp->smc_smcmr, smcr_mk_clen(bits - 1) | cval | SMCMR_SM_UART | prev_mode); } else { unsigned int bits = tty_get_char_size(termios->c_cflag); out_be16(&pinfo->sccup->scc_genscc.scc_mrblr, pinfo->rx_fifosize); out_be16(&pinfo->sccup->scc_maxidl, maxidl); out_be16(&sccp->scc_psmr, (UART_LCR_WLEN(bits) << 12) | scval); } if (pinfo->clk) clk_set_rate(pinfo->clk, baud); else cpm_setbrg(pinfo->brg - 1, baud); uart_port_unlock_irqrestore(port, flags); } static const char *cpm_uart_type(struct uart_port *port) { pr_debug("CPM uart[%d]:uart_type\n", port->line); return port->type == PORT_CPM ? "CPM UART" : NULL; } /* * verify the new serial_struct (for TIOCSSERIAL). */ static int cpm_uart_verify_port(struct uart_port *port, struct serial_struct *ser) { int ret = 0; pr_debug("CPM uart[%d]:verify_port\n", port->line); if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM) ret = -EINVAL; if (ser->irq < 0 || ser->irq >= irq_get_nr_irqs()) ret = -EINVAL; if (ser->baud_base < 9600) ret = -EINVAL; return ret; } /* * Transmit characters, refill buffer descriptor, if possible */ static int cpm_uart_tx_pump(struct uart_port *port) { cbd_t __iomem *bdp; u8 *p; int count; struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); struct tty_port *tport = &port->state->port; /* Handle xon/xoff */ if (port->x_char) { /* Pick next descriptor and fill from buffer */ bdp = pinfo->tx_cur; p = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo); *p++ = port->x_char; out_be16(&bdp->cbd_datlen, 1); setbits16(&bdp->cbd_sc, BD_SC_READY); /* Get next BD. */ if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP) bdp = pinfo->tx_bd_base; else bdp++; pinfo->tx_cur = bdp; port->icount.tx++; port->x_char = 0; return 1; } if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) { cpm_uart_stop_tx(port); return 0; } /* Pick next descriptor and fill from buffer */ bdp = pinfo->tx_cur; while (!(in_be16(&bdp->cbd_sc) & BD_SC_READY) && !kfifo_is_empty(&tport->xmit_fifo)) { p = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo); count = uart_fifo_out(port, p, pinfo->tx_fifosize); out_be16(&bdp->cbd_datlen, count); setbits16(&bdp->cbd_sc, BD_SC_READY); /* Get next BD. */ if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP) bdp = pinfo->tx_bd_base; else bdp++; } pinfo->tx_cur = bdp; if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) uart_write_wakeup(port); if (kfifo_is_empty(&tport->xmit_fifo)) { cpm_uart_stop_tx(port); return 0; } return 1; } /* * init buffer descriptors */ static void cpm_uart_initbd(struct uart_cpm_port *pinfo) { int i; u8 *mem_addr; cbd_t __iomem *bdp; pr_debug("CPM uart[%d]:initbd\n", pinfo->port.line); /* Set the physical address of the host memory * buffers in the buffer descriptors, and the * virtual address for us to work with. */ mem_addr = pinfo->mem_addr; bdp = pinfo->rx_cur = pinfo->rx_bd_base; for (i = 0; i < (pinfo->rx_nrfifos - 1); i++, bdp++) { out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo)); out_be16(&bdp->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT); mem_addr += pinfo->rx_fifosize; } out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo)); out_be16(&bdp->cbd_sc, BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT); /* Set the physical address of the host memory * buffers in the buffer descriptors, and the * virtual address for us to work with. */ mem_addr = pinfo->mem_addr + L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize); bdp = pinfo->tx_cur = pinfo->tx_bd_base; for (i = 0; i < (pinfo->tx_nrfifos - 1); i++, bdp++) { out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo)); out_be16(&bdp->cbd_sc, BD_SC_INTRPT); mem_addr += pinfo->tx_fifosize; } out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo)); out_be16(&bdp->cbd_sc, BD_SC_WRAP | BD_SC_INTRPT); } static void cpm_uart_init_scc(struct uart_cpm_port *pinfo) { scc_t __iomem *scp; scc_uart_t __iomem *sup; pr_debug("CPM uart[%d]:init_scc\n", pinfo->port.line); scp = pinfo->sccp; sup = pinfo->sccup; /* Store address */ out_be16(&pinfo->sccup->scc_genscc.scc_rbase, (u8 __iomem *)pinfo->rx_bd_base - DPRAM_BASE); out_be16(&pinfo->sccup->scc_genscc.scc_tbase, (u8 __iomem *)pinfo->tx_bd_base - DPRAM_BASE); /* Set up the uart parameters in the * parameter ram. */ out_8(&sup->scc_genscc.scc_rfcr, CPMFCR_GBL | CPMFCR_EB); out_8(&sup->scc_genscc.scc_tfcr, CPMFCR_GBL | CPMFCR_EB); out_be16(&sup->scc_genscc.scc_mrblr, pinfo->rx_fifosize); out_be16(&sup->scc_maxidl, 0x10); out_be16(&sup->scc_brkcr, 1); out_be16(&sup->scc_parec, 0); out_be16(&sup->scc_frmec, 0); out_be16(&sup->scc_nosec, 0); out_be16(&sup->scc_brkec, 0); out_be16(&sup->scc_uaddr1, 0); out_be16(&sup->scc_uaddr2, 0); out_be16(&sup->scc_toseq, 0); out_be16(&sup->scc_char1, 0x8000); out_be16(&sup->scc_char2, 0x8000); out_be16(&sup->scc_char3, 0x8000); out_be16(&sup->scc_char4, 0x8000); out_be16(&sup->scc_char5, 0x8000); out_be16(&sup->scc_char6, 0x8000); out_be16(&sup->scc_char7, 0x8000); out_be16(&sup->scc_char8, 0x8000); out_be16(&sup->scc_rccm, 0xc0ff); /* Send the CPM an initialize command. */ cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX); /* Set UART mode, 8 bit, no parity, one stop. * Enable receive and transmit. */ out_be32(&scp->scc_gsmrh, 0); out_be32(&scp->scc_gsmrl, SCC_GSMRL_MODE_UART | SCC_GSMRL_TDCR_16 | SCC_GSMRL_RDCR_16); /* Enable rx interrupts and clear all pending events. */ out_be16(&scp->scc_sccm, 0); out_be16(&scp->scc_scce, 0xffff); out_be16(&scp->scc_dsr, 0x7e7e); out_be16(&scp->scc_psmr, 0x3000); setbits32(&scp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT); } static void cpm_uart_init_smc(struct uart_cpm_port *pinfo) { smc_t __iomem *sp; smc_uart_t __iomem *up; pr_debug("CPM uart[%d]:init_smc\n", pinfo->port.line); sp = pinfo->smcp; up = pinfo->smcup; /* Store address */ out_be16(&pinfo->smcup->smc_rbase, (u8 __iomem *)pinfo->rx_bd_base - DPRAM_BASE); out_be16(&pinfo->smcup->smc_tbase, (u8 __iomem *)pinfo->tx_bd_base - DPRAM_BASE); /* * In case SMC is being relocated... */ out_be16(&up->smc_rbptr, in_be16(&pinfo->smcup->smc_rbase)); out_be16(&up->smc_tbptr, in_be16(&pinfo->smcup->smc_tbase)); out_be32(&up->smc_rstate, 0); out_be32(&up->smc_tstate, 0); out_be16(&up->smc_brkcr, 1); /* number of break chars */ out_be16(&up->smc_brkec, 0); /* Set up the uart parameters in the * parameter ram. */ out_8(&up->smc_rfcr, CPMFCR_GBL | CPMFCR_EB); out_8(&up->smc_tfcr, CPMFCR_GBL | CPMFCR_EB); /* Using idle character time requires some additional tuning. */ out_be16(&up->smc_mrblr, pinfo->rx_fifosize); out_be16(&up->smc_maxidl, 0x10); out_be16(&up->smc_brklen, 0); out_be16(&up->smc_brkec, 0); out_be16(&up->smc_brkcr, 1); /* Set UART mode, 8 bit, no parity, one stop. * Enable receive and transmit. */ out_be16(&sp->smc_smcmr, smcr_mk_clen(9) | SMCMR_SM_UART); /* Enable only rx interrupts clear all pending events. */ out_8(&sp->smc_smcm, 0); out_8(&sp->smc_smce, 0xff); setbits16(&sp->smc_smcmr, SMCMR_REN | SMCMR_TEN); } /* * Allocate DP-Ram and memory buffers. We need to allocate a transmit and * receive buffer descriptors from dual port ram, and a character * buffer area from host mem. If we are allocating for the console we need * to do it from bootmem */ static int cpm_uart_allocbuf(struct uart_cpm_port *pinfo, unsigned int is_con) { int dpmemsz, memsz; u8 __iomem *dp_mem; unsigned long dp_offset; u8 *mem_addr; dma_addr_t dma_addr = 0; pr_debug("CPM uart[%d]:allocbuf\n", pinfo->port.line); dpmemsz = sizeof(cbd_t) * (pinfo->rx_nrfifos + pinfo->tx_nrfifos); dp_offset = cpm_muram_alloc(dpmemsz, 8); if (IS_ERR_VALUE(dp_offset)) { pr_err("%s: could not allocate buffer descriptors\n", __func__); return -ENOMEM; } dp_mem = cpm_muram_addr(dp_offset); memsz = L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) + L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize); if (IS_ENABLED(CONFIG_CPM1) && is_con) { /* was hostalloc but changed cause it blows away the */ /* large tlb mapping when pinning the kernel area */ mem_addr = (u8 __force *)cpm_muram_addr(cpm_muram_alloc(memsz, 8)); dma_addr = cpm_muram_dma((void __iomem *)mem_addr); } else if (is_con) { mem_addr = kzalloc(memsz, GFP_NOWAIT); dma_addr = virt_to_bus(mem_addr); } else { mem_addr = dma_alloc_coherent(pinfo->port.dev, memsz, &dma_addr, GFP_KERNEL); } if (!mem_addr) { cpm_muram_free(dp_offset); pr_err("%s: could not allocate coherent memory\n", __func__); return -ENOMEM; } pinfo->dp_addr = dp_offset; pinfo->mem_addr = mem_addr; pinfo->dma_addr = dma_addr; pinfo->mem_size = memsz; pinfo->rx_buf = mem_addr; pinfo->tx_buf = pinfo->rx_buf + L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize); pinfo->rx_bd_base = (cbd_t __iomem *)dp_mem; pinfo->tx_bd_base = pinfo->rx_bd_base + pinfo->rx_nrfifos; return 0; } static void cpm_uart_freebuf(struct uart_cpm_port *pinfo) { dma_free_coherent(pinfo->port.dev, L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) + L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize), (void __force *)pinfo->mem_addr, pinfo->dma_addr); cpm_muram_free(pinfo->dp_addr); } /* * Initialize port. This is called from early_console stuff * so we have to be careful here ! */ static int cpm_uart_request_port(struct uart_port *port) { struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); int ret; pr_debug("CPM uart[%d]:request port\n", port->line); if (pinfo->flags & FLAG_CONSOLE) return 0; if (IS_SMC(pinfo)) { clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX | SMCM_TX); clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN); } else { clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX); clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT); } ret = cpm_uart_allocbuf(pinfo, 0); if (ret) return ret; cpm_uart_initbd(pinfo); if (IS_SMC(pinfo)) cpm_uart_init_smc(pinfo); else cpm_uart_init_scc(pinfo); return 0; } static void cpm_uart_release_port(struct uart_port *port) { struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); if (!(pinfo->flags & FLAG_CONSOLE)) cpm_uart_freebuf(pinfo); } /* * Configure/autoconfigure the port. */ static void cpm_uart_config_port(struct uart_port *port, int flags) { pr_debug("CPM uart[%d]:config_port\n", port->line); if (flags & UART_CONFIG_TYPE) { port->type = PORT_CPM; cpm_uart_request_port(port); } } #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_CPM_CONSOLE) /* * Write a string to the serial port * Note that this is called with interrupts already disabled */ static void cpm_uart_early_write(struct uart_cpm_port *pinfo, const char *string, u_int count, bool handle_linefeed) { unsigned int i; cbd_t __iomem *bdp, *bdbase; unsigned char *cpm_outp_addr; /* Get the address of the host memory buffer. */ bdp = pinfo->tx_cur; bdbase = pinfo->tx_bd_base; /* * Now, do each character. This is not as bad as it looks * since this is a holding FIFO and not a transmitting FIFO. * We could add the complexity of filling the entire transmit * buffer, but we would just wait longer between accesses...... */ for (i = 0; i < count; i++, string++) { /* Wait for transmitter fifo to empty. * Ready indicates output is ready, and xmt is doing * that, not that it is ready for us to send. */ while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0) ; /* Send the character out. * If the buffer address is in the CPM DPRAM, don't * convert it. */ cpm_outp_addr = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo); *cpm_outp_addr = *string; out_be16(&bdp->cbd_datlen, 1); setbits16(&bdp->cbd_sc, BD_SC_READY); if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP) bdp = bdbase; else bdp++; /* if a LF, also do CR... */ if (handle_linefeed && *string == 10) { while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0) ; cpm_outp_addr = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo); *cpm_outp_addr = 13; out_be16(&bdp->cbd_datlen, 1); setbits16(&bdp->cbd_sc, BD_SC_READY); if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP) bdp = bdbase; else bdp++; } } /* * Finally, Wait for transmitter & holding register to empty * and restore the IER */ while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0) ; pinfo->tx_cur = bdp; } #endif #ifdef CONFIG_CONSOLE_POLL /* Serial polling routines for writing and reading from the uart while * in an interrupt or debug context. */ #define GDB_BUF_SIZE 512 /* power of 2, please */ static char poll_buf[GDB_BUF_SIZE]; static char *pollp; static int poll_chars; static int poll_wait_key(char *obuf, struct uart_cpm_port *pinfo) { u_char c, *cp; volatile cbd_t *bdp; int i; /* Get the address of the host memory buffer. */ bdp = pinfo->rx_cur; if (bdp->cbd_sc & BD_SC_EMPTY) return NO_POLL_CHAR; /* If the buffer address is in the CPM DPRAM, don't * convert it. */ cp = cpm2cpu_addr(bdp->cbd_bufaddr, pinfo); if (obuf) { i = c = bdp->cbd_datlen; while (i-- > 0) *obuf++ = *cp++; } else c = *cp; bdp->cbd_sc &= ~(BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV | BD_SC_ID); bdp->cbd_sc |= BD_SC_EMPTY; if (bdp->cbd_sc & BD_SC_WRAP) bdp = pinfo->rx_bd_base; else bdp++; pinfo->rx_cur = (cbd_t *)bdp; return (int)c; } static int cpm_get_poll_char(struct uart_port *port) { struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); if (!serial_polled) { serial_polled = 1; poll_chars = 0; } if (poll_chars <= 0) { int ret = poll_wait_key(poll_buf, pinfo); if (ret == NO_POLL_CHAR) return ret; poll_chars = ret; pollp = poll_buf; } poll_chars--; return *pollp++; } static void cpm_put_poll_char(struct uart_port *port, unsigned char c) { struct uart_cpm_port *pinfo = container_of(port, struct uart_cpm_port, port); static char ch[2]; ch[0] = (char)c; cpm_uart_early_write(pinfo, ch, 1, false); } #ifdef CONFIG_SERIAL_CPM_CONSOLE static struct uart_port *udbg_port; static void udbg_cpm_putc(char c) { if (c == '\n') cpm_put_poll_char(udbg_port, '\r'); cpm_put_poll_char(udbg_port, c); } static int udbg_cpm_getc_poll(void) { int c = cpm_get_poll_char(udbg_port); return c == NO_POLL_CHAR ? -1 : c; } static int udbg_cpm_getc(void) { int c; while ((c = udbg_cpm_getc_poll()) == -1) cpu_relax(); return c; } #endif /* CONFIG_SERIAL_CPM_CONSOLE */ #endif /* CONFIG_CONSOLE_POLL */ static const struct uart_ops cpm_uart_pops = { .tx_empty = cpm_uart_tx_empty, .set_mctrl = cpm_uart_set_mctrl, .get_mctrl = cpm_uart_get_mctrl, .stop_tx = cpm_uart_stop_tx, .start_tx = cpm_uart_start_tx, .stop_rx = cpm_uart_stop_rx, .break_ctl = cpm_uart_break_ctl, .startup = cpm_uart_startup, .shutdown = cpm_uart_shutdown, .set_termios = cpm_uart_set_termios, .type = cpm_uart_type, .release_port = cpm_uart_release_port, .request_port = cpm_uart_request_port, .config_port = cpm_uart_config_port, .verify_port = cpm_uart_verify_port, #ifdef CONFIG_CONSOLE_POLL .poll_get_char = cpm_get_poll_char, .poll_put_char = cpm_put_poll_char, #endif }; static struct uart_cpm_port cpm_uart_ports[UART_NR]; static void __iomem *cpm_uart_map_pram(struct uart_cpm_port *port, struct device_node *np) { void __iomem *pram; unsigned long offset; struct resource res; resource_size_t len; /* Don't remap parameter RAM if it has already been initialized * during console setup. */ if (IS_SMC(port) && port->smcup) return port->smcup; else if (!IS_SMC(port) && port->sccup) return port->sccup; if (of_address_to_resource(np, 1, &res)) return NULL; len = resource_size(&res); pram = ioremap(res.start, len); if (!pram) return NULL; if (!IS_ENABLED(CONFIG_CPM2) || !IS_SMC(port)) return pram; if (len != 2) { pr_warn("cpm_uart[%d]: device tree references " "SMC pram, using boot loader/wrapper pram mapping. " "Please fix your device tree to reference the pram " "base register instead.\n", port->port.line); return pram; } offset = cpm_muram_alloc(64, 64); out_be16(pram, offset); iounmap(pram); return cpm_muram_addr(offset); } static void cpm_uart_unmap_pram(struct uart_cpm_port *port, void __iomem *pram) { if (!IS_ENABLED(CONFIG_CPM2) || !IS_SMC(port)) iounmap(pram); } static int cpm_uart_init_port(struct device_node *np, struct uart_cpm_port *pinfo) { const u32 *data; void __iomem *mem, *pram; struct device *dev = pinfo->port.dev; int len; int ret; int i; data = of_get_property(np, "clock", NULL); if (data) { struct clk *clk = clk_get(NULL, (const char*)data); if (!IS_ERR(clk)) pinfo->clk = clk; } if (!pinfo->clk) { data = of_get_property(np, "fsl,cpm-brg", &len); if (!data || len != 4) { printk(KERN_ERR "CPM UART %pOFn has no/invalid " "fsl,cpm-brg property.\n", np); return -EINVAL; } pinfo->brg = *data; } data = of_get_property(np, "fsl,cpm-command", &len); if (!data || len != 4) { printk(KERN_ERR "CPM UART %pOFn has no/invalid " "fsl,cpm-command property.\n", np); return -EINVAL; } pinfo->command = *data; mem = of_iomap(np, 0); if (!mem) return -ENOMEM; if (of_device_is_compatible(np, "fsl,cpm1-scc-uart") || of_device_is_compatible(np, "fsl,cpm2-scc-uart")) { pinfo->sccp = mem; pinfo->sccup = pram = cpm_uart_map_pram(pinfo, np); } else if (of_device_is_compatible(np, "fsl,cpm1-smc-uart") || of_device_is_compatible(np, "fsl,cpm2-smc-uart")) { pinfo->flags |= FLAG_SMC; pinfo->smcp = mem; pinfo->smcup = pram = cpm_uart_map_pram(pinfo, np); } else { ret = -ENODEV; goto out_mem; } if (!pram) { ret = -ENOMEM; goto out_mem; } pinfo->tx_nrfifos = TX_NUM_FIFO; pinfo->tx_fifosize = TX_BUF_SIZE; pinfo->rx_nrfifos = RX_NUM_FIFO; pinfo->rx_fifosize = RX_BUF_SIZE; pinfo->port.uartclk = ppc_proc_freq; pinfo->port.mapbase = (unsigned long)mem; pinfo->port.type = PORT_CPM; pinfo->port.ops = &cpm_uart_pops; pinfo->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_CPM_CONSOLE); pinfo->port.iotype = UPIO_MEM; pinfo->port.fifosize = pinfo->tx_nrfifos * pinfo->tx_fifosize; spin_lock_init(&pinfo->port.lock); for (i = 0; i < NUM_GPIOS; i++) { struct gpio_desc *gpiod; pinfo->gpios[i] = NULL; gpiod = devm_gpiod_get_index_optional(dev, NULL, i, GPIOD_ASIS); if (IS_ERR(gpiod)) { ret = PTR_ERR(gpiod); goto out_pram; } if (gpiod) { if (i == GPIO_RTS || i == GPIO_DTR) ret = gpiod_direction_output(gpiod, 0); else ret = gpiod_direction_input(gpiod); if (ret) { pr_err("can't set direction for gpio #%d: %d\n", i, ret); continue; } pinfo->gpios[i] = gpiod; } } #ifdef CONFIG_PPC_EARLY_DEBUG_CPM #if defined(CONFIG_CONSOLE_POLL) && defined(CONFIG_SERIAL_CPM_CONSOLE) if (!udbg_port) #endif udbg_putc = NULL; #endif return cpm_uart_request_port(&pinfo->port); out_pram: cpm_uart_unmap_pram(pinfo, pram); out_mem: iounmap(mem); return ret; } #ifdef CONFIG_SERIAL_CPM_CONSOLE /* * Print a string to the serial port trying not to disturb * any possible real use of the port... * * Note that this is called with interrupts already disabled */ static void cpm_uart_console_write(struct console *co, const char *s, u_int count) { struct uart_cpm_port *pinfo = &cpm_uart_ports[co->index]; unsigned long flags; if (unlikely(oops_in_progress)) { local_irq_save(flags); cpm_uart_early_write(pinfo, s, count, true); local_irq_restore(flags); } else { uart_port_lock_irqsave(&pinfo->port, &flags); cpm_uart_early_write(pinfo, s, count, true); uart_port_unlock_irqrestore(&pinfo->port, flags); } } static int __init cpm_uart_console_setup(struct console *co, char *options) { int baud = 38400; int bits = 8; int parity = 'n'; int flow = 'n'; int ret; struct uart_cpm_port *pinfo; struct uart_port *port; struct device_node *np; int i = 0; if (co->index >= UART_NR) { printk(KERN_ERR "cpm_uart: console index %d too high\n", co->index); return -ENODEV; } for_each_node_by_type(np, "serial") { if (!of_device_is_compatible(np, "fsl,cpm1-smc-uart") && !of_device_is_compatible(np, "fsl,cpm1-scc-uart") && !of_device_is_compatible(np, "fsl,cpm2-smc-uart") && !of_device_is_compatible(np, "fsl,cpm2-scc-uart")) continue; if (i++ == co->index) break; } if (!np) return -ENODEV; pinfo = &cpm_uart_ports[co->index]; pinfo->flags |= FLAG_CONSOLE; port = &pinfo->port; ret = cpm_uart_init_port(np, pinfo); of_node_put(np); if (ret) return ret; if (options) { uart_parse_options(options, &baud, &parity, &bits, &flow); } else { baud = get_baudrate(); if (baud == -1) baud = 9600; } if (IS_SMC(pinfo)) { out_be16(&pinfo->smcup->smc_brkcr, 0); cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX); clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX | SMCM_TX); clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN); } else { out_be16(&pinfo->sccup->scc_brkcr, 0); cpm_line_cr_cmd(pinfo, CPM_CR_GRA_STOP_TX); clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX); clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT); } ret = cpm_uart_allocbuf(pinfo, 1); if (ret) return ret; cpm_uart_initbd(pinfo); if (IS_SMC(pinfo)) cpm_uart_init_smc(pinfo); else cpm_uart_init_scc(pinfo); uart_set_options(port, co, baud, parity, bits, flow); cpm_line_cr_cmd(pinfo, CPM_CR_RESTART_TX); #ifdef CONFIG_CONSOLE_POLL if (!udbg_port) { udbg_port = &pinfo->port; udbg_putc = udbg_cpm_putc; udbg_getc = udbg_cpm_getc; udbg_getc_poll = udbg_cpm_getc_poll; } #endif return 0; } static struct uart_driver cpm_reg; static struct console cpm_scc_uart_console = { .name = "ttyCPM", .write = cpm_uart_console_write, .device = uart_console_device, .setup = cpm_uart_console_setup, .flags = CON_PRINTBUFFER, .index = -1, .data = &cpm_reg, }; static int __init cpm_uart_console_init(void) { cpm_muram_init(); register_console(&cpm_scc_uart_console); return 0; } console_initcall(cpm_uart_console_init); #define CPM_UART_CONSOLE &cpm_scc_uart_console #else #define CPM_UART_CONSOLE NULL #endif static struct uart_driver cpm_reg = { .owner = THIS_MODULE, .driver_name = "ttyCPM", .dev_name = "ttyCPM", .major = SERIAL_CPM_MAJOR, .minor = SERIAL_CPM_MINOR, .cons = CPM_UART_CONSOLE, .nr = UART_NR, }; static int probe_index; static int cpm_uart_probe(struct platform_device *ofdev) { int index = probe_index++; struct uart_cpm_port *pinfo = &cpm_uart_ports[index]; int ret; pinfo->port.line = index; if (index >= UART_NR) return -ENODEV; platform_set_drvdata(ofdev, pinfo); /* initialize the device pointer for the port */ pinfo->port.dev = &ofdev->dev; pinfo->port.irq = irq_of_parse_and_map(ofdev->dev.of_node, 0); if (!pinfo->port.irq) return -EINVAL; ret = cpm_uart_init_port(ofdev->dev.of_node, pinfo); if (!ret) return uart_add_one_port(&cpm_reg, &pinfo->port); irq_dispose_mapping(pinfo->port.irq); return ret; } static void cpm_uart_remove(struct platform_device *ofdev) { struct uart_cpm_port *pinfo = platform_get_drvdata(ofdev); uart_remove_one_port(&cpm_reg, &pinfo->port); } static const struct of_device_id cpm_uart_match[] = { { .compatible = "fsl,cpm1-smc-uart", }, { .compatible = "fsl,cpm1-scc-uart", }, { .compatible = "fsl,cpm2-smc-uart", }, { .compatible = "fsl,cpm2-scc-uart", }, {} }; MODULE_DEVICE_TABLE(of, cpm_uart_match); static struct platform_driver cpm_uart_driver = { .driver = { .name = "cpm_uart", .of_match_table = cpm_uart_match, }, .probe = cpm_uart_probe, .remove = cpm_uart_remove, }; static int __init cpm_uart_init(void) { int ret = uart_register_driver(&cpm_reg); if (ret) return ret; ret = platform_driver_register(&cpm_uart_driver); if (ret) uart_unregister_driver(&cpm_reg); return ret; } static void __exit cpm_uart_exit(void) { platform_driver_unregister(&cpm_uart_driver); uart_unregister_driver(&cpm_reg); } module_init(cpm_uart_init); module_exit(cpm_uart_exit); MODULE_AUTHOR("Kumar Gala/Antoniou Pantelis"); MODULE_DESCRIPTION("CPM SCC/SMC port driver $Revision: 0.01 $"); MODULE_LICENSE("GPL"); MODULE_ALIAS_CHARDEV(SERIAL_CPM_MAJOR, SERIAL_CPM_MINOR);