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linux/linux-5.18.11/drivers/tty/serial/mpc52xx_uart.c

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// SPDX-License-Identifier: GPL-2.0
/*
* Driver for the PSC of the Freescale MPC52xx PSCs configured as UARTs.
*
* FIXME According to the usermanual the status bits in the status register
* are only updated when the peripherals access the FIFO and not when the
* CPU access them. So since we use this bits to know when we stop writing
* and reading, they may not be updated in-time and a race condition may
* exists. But I haven't be able to prove this and I don't care. But if
* any problem arises, it might worth checking. The TX/RX FIFO Stats
* registers should be used in addition.
* Update: Actually, they seem updated ... At least the bits we use.
*
*
* Maintainer : Sylvain Munaut <tnt@246tNt.com>
*
* Some of the code has been inspired/copied from the 2.4 code written
* by Dale Farnsworth <dfarnsworth@mvista.com>.
*
* Copyright (C) 2008 Freescale Semiconductor Inc.
* John Rigby <jrigby@gmail.com>
* Added support for MPC5121
* Copyright (C) 2006 Secret Lab Technologies Ltd.
* Grant Likely <grant.likely@secretlab.ca>
* Copyright (C) 2004-2006 Sylvain Munaut <tnt@246tNt.com>
* Copyright (C) 2003 MontaVista, Software, Inc.
*/
#undef DEBUG
#include <linux/device.h>
#include <linux/module.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial.h>
#include <linux/sysrq.h>
#include <linux/console.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/clk.h>
#include <asm/mpc52xx.h>
#include <asm/mpc52xx_psc.h>
#include <linux/serial_core.h>
/* We've been assigned a range on the "Low-density serial ports" major */
#define SERIAL_PSC_MAJOR 204
#define SERIAL_PSC_MINOR 148
#define ISR_PASS_LIMIT 256 /* Max number of iteration in the interrupt */
static struct uart_port mpc52xx_uart_ports[MPC52xx_PSC_MAXNUM];
/* Rem: - We use the read_status_mask as a shadow of
* psc->mpc52xx_psc_imr
* - It's important that is array is all zero on start as we
* use it to know if it's initialized or not ! If it's not sure
* it's cleared, then a memset(...,0,...) should be added to
* the console_init
*/
/* lookup table for matching device nodes to index numbers */
static struct device_node *mpc52xx_uart_nodes[MPC52xx_PSC_MAXNUM];
static void mpc52xx_uart_of_enumerate(void);
#define PSC(port) ((struct mpc52xx_psc __iomem *)((port)->membase))
/* Forward declaration of the interruption handling routine */
static irqreturn_t mpc52xx_uart_int(int irq, void *dev_id);
static irqreturn_t mpc5xxx_uart_process_int(struct uart_port *port);
/* ======================================================================== */
/* PSC fifo operations for isolating differences between 52xx and 512x */
/* ======================================================================== */
struct psc_ops {
void (*fifo_init)(struct uart_port *port);
unsigned int (*raw_rx_rdy)(struct uart_port *port);
unsigned int (*raw_tx_rdy)(struct uart_port *port);
unsigned int (*rx_rdy)(struct uart_port *port);
unsigned int (*tx_rdy)(struct uart_port *port);
unsigned int (*tx_empty)(struct uart_port *port);
void (*stop_rx)(struct uart_port *port);
void (*start_tx)(struct uart_port *port);
void (*stop_tx)(struct uart_port *port);
void (*rx_clr_irq)(struct uart_port *port);
void (*tx_clr_irq)(struct uart_port *port);
void (*write_char)(struct uart_port *port, unsigned char c);
unsigned char (*read_char)(struct uart_port *port);
void (*cw_disable_ints)(struct uart_port *port);
void (*cw_restore_ints)(struct uart_port *port);
unsigned int (*set_baudrate)(struct uart_port *port,
struct ktermios *new,
struct ktermios *old);
int (*clock_alloc)(struct uart_port *port);
void (*clock_relse)(struct uart_port *port);
int (*clock)(struct uart_port *port, int enable);
int (*fifoc_init)(void);
void (*fifoc_uninit)(void);
void (*get_irq)(struct uart_port *, struct device_node *);
irqreturn_t (*handle_irq)(struct uart_port *port);
u16 (*get_status)(struct uart_port *port);
u8 (*get_ipcr)(struct uart_port *port);
void (*command)(struct uart_port *port, u8 cmd);
void (*set_mode)(struct uart_port *port, u8 mr1, u8 mr2);
void (*set_rts)(struct uart_port *port, int state);
void (*enable_ms)(struct uart_port *port);
void (*set_sicr)(struct uart_port *port, u32 val);
void (*set_imr)(struct uart_port *port, u16 val);
u8 (*get_mr1)(struct uart_port *port);
};
/* setting the prescaler and divisor reg is common for all chips */
static inline void mpc52xx_set_divisor(struct mpc52xx_psc __iomem *psc,
u16 prescaler, unsigned int divisor)
{
/* select prescaler */
out_be16(&psc->mpc52xx_psc_clock_select, prescaler);
out_8(&psc->ctur, divisor >> 8);
out_8(&psc->ctlr, divisor & 0xff);
}
static u16 mpc52xx_psc_get_status(struct uart_port *port)
{
return in_be16(&PSC(port)->mpc52xx_psc_status);
}
static u8 mpc52xx_psc_get_ipcr(struct uart_port *port)
{
return in_8(&PSC(port)->mpc52xx_psc_ipcr);
}
static void mpc52xx_psc_command(struct uart_port *port, u8 cmd)
{
out_8(&PSC(port)->command, cmd);
}
static void mpc52xx_psc_set_mode(struct uart_port *port, u8 mr1, u8 mr2)
{
out_8(&PSC(port)->command, MPC52xx_PSC_SEL_MODE_REG_1);
out_8(&PSC(port)->mode, mr1);
out_8(&PSC(port)->mode, mr2);
}
static void mpc52xx_psc_set_rts(struct uart_port *port, int state)
{
if (state)
out_8(&PSC(port)->op1, MPC52xx_PSC_OP_RTS);
else
out_8(&PSC(port)->op0, MPC52xx_PSC_OP_RTS);
}
static void mpc52xx_psc_enable_ms(struct uart_port *port)
{
struct mpc52xx_psc __iomem *psc = PSC(port);
/* clear D_*-bits by reading them */
in_8(&psc->mpc52xx_psc_ipcr);
/* enable CTS and DCD as IPC interrupts */
out_8(&psc->mpc52xx_psc_acr, MPC52xx_PSC_IEC_CTS | MPC52xx_PSC_IEC_DCD);
port->read_status_mask |= MPC52xx_PSC_IMR_IPC;
out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
}
static void mpc52xx_psc_set_sicr(struct uart_port *port, u32 val)
{
out_be32(&PSC(port)->sicr, val);
}
static void mpc52xx_psc_set_imr(struct uart_port *port, u16 val)
{
out_be16(&PSC(port)->mpc52xx_psc_imr, val);
}
static u8 mpc52xx_psc_get_mr1(struct uart_port *port)
{
out_8(&PSC(port)->command, MPC52xx_PSC_SEL_MODE_REG_1);
return in_8(&PSC(port)->mode);
}
#ifdef CONFIG_PPC_MPC52xx
#define FIFO_52xx(port) ((struct mpc52xx_psc_fifo __iomem *)(PSC(port)+1))
static void mpc52xx_psc_fifo_init(struct uart_port *port)
{
struct mpc52xx_psc __iomem *psc = PSC(port);
struct mpc52xx_psc_fifo __iomem *fifo = FIFO_52xx(port);
out_8(&fifo->rfcntl, 0x00);
out_be16(&fifo->rfalarm, 0x1ff);
out_8(&fifo->tfcntl, 0x07);
out_be16(&fifo->tfalarm, 0x80);
port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY | MPC52xx_PSC_IMR_TXRDY;
out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
}
static unsigned int mpc52xx_psc_raw_rx_rdy(struct uart_port *port)
{
return in_be16(&PSC(port)->mpc52xx_psc_status)
& MPC52xx_PSC_SR_RXRDY;
}
static unsigned int mpc52xx_psc_raw_tx_rdy(struct uart_port *port)
{
return in_be16(&PSC(port)->mpc52xx_psc_status)
& MPC52xx_PSC_SR_TXRDY;
}
static unsigned int mpc52xx_psc_rx_rdy(struct uart_port *port)
{
return in_be16(&PSC(port)->mpc52xx_psc_isr)
& port->read_status_mask
& MPC52xx_PSC_IMR_RXRDY;
}
static unsigned int mpc52xx_psc_tx_rdy(struct uart_port *port)
{
return in_be16(&PSC(port)->mpc52xx_psc_isr)
& port->read_status_mask
& MPC52xx_PSC_IMR_TXRDY;
}
static unsigned int mpc52xx_psc_tx_empty(struct uart_port *port)
{
u16 sts = in_be16(&PSC(port)->mpc52xx_psc_status);
return (sts & MPC52xx_PSC_SR_TXEMP) ? TIOCSER_TEMT : 0;
}
static void mpc52xx_psc_start_tx(struct uart_port *port)
{
port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY;
out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
}
static void mpc52xx_psc_stop_tx(struct uart_port *port)
{
port->read_status_mask &= ~MPC52xx_PSC_IMR_TXRDY;
out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
}
static void mpc52xx_psc_stop_rx(struct uart_port *port)
{
port->read_status_mask &= ~MPC52xx_PSC_IMR_RXRDY;
out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
}
static void mpc52xx_psc_rx_clr_irq(struct uart_port *port)
{
}
static void mpc52xx_psc_tx_clr_irq(struct uart_port *port)
{
}
static void mpc52xx_psc_write_char(struct uart_port *port, unsigned char c)
{
out_8(&PSC(port)->mpc52xx_psc_buffer_8, c);
}
static unsigned char mpc52xx_psc_read_char(struct uart_port *port)
{
return in_8(&PSC(port)->mpc52xx_psc_buffer_8);
}
static void mpc52xx_psc_cw_disable_ints(struct uart_port *port)
{
out_be16(&PSC(port)->mpc52xx_psc_imr, 0);
}
static void mpc52xx_psc_cw_restore_ints(struct uart_port *port)
{
out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
}
static unsigned int mpc5200_psc_set_baudrate(struct uart_port *port,
struct ktermios *new,
struct ktermios *old)
{
unsigned int baud;
unsigned int divisor;
/* The 5200 has a fixed /32 prescaler, uartclk contains the ipb freq */
baud = uart_get_baud_rate(port, new, old,
port->uartclk / (32 * 0xffff) + 1,
port->uartclk / 32);
divisor = (port->uartclk + 16 * baud) / (32 * baud);
/* enable the /32 prescaler and set the divisor */
mpc52xx_set_divisor(PSC(port), 0xdd00, divisor);
return baud;
}
static unsigned int mpc5200b_psc_set_baudrate(struct uart_port *port,
struct ktermios *new,
struct ktermios *old)
{
unsigned int baud;
unsigned int divisor;
u16 prescaler;
/* The 5200B has a selectable /4 or /32 prescaler, uartclk contains the
* ipb freq */
baud = uart_get_baud_rate(port, new, old,
port->uartclk / (32 * 0xffff) + 1,
port->uartclk / 4);
divisor = (port->uartclk + 2 * baud) / (4 * baud);
/* select the proper prescaler and set the divisor
* prefer high prescaler for more tolerance on low baudrates */
if (divisor > 0xffff || baud <= 115200) {
divisor = (divisor + 4) / 8;
prescaler = 0xdd00; /* /32 */
} else
prescaler = 0xff00; /* /4 */
mpc52xx_set_divisor(PSC(port), prescaler, divisor);
return baud;
}
static void mpc52xx_psc_get_irq(struct uart_port *port, struct device_node *np)
{
port->irqflags = 0;
port->irq = irq_of_parse_and_map(np, 0);
}
/* 52xx specific interrupt handler. The caller holds the port lock */
static irqreturn_t mpc52xx_psc_handle_irq(struct uart_port *port)
{
return mpc5xxx_uart_process_int(port);
}
static const struct psc_ops mpc52xx_psc_ops = {
.fifo_init = mpc52xx_psc_fifo_init,
.raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
.raw_tx_rdy = mpc52xx_psc_raw_tx_rdy,
.rx_rdy = mpc52xx_psc_rx_rdy,
.tx_rdy = mpc52xx_psc_tx_rdy,
.tx_empty = mpc52xx_psc_tx_empty,
.stop_rx = mpc52xx_psc_stop_rx,
.start_tx = mpc52xx_psc_start_tx,
.stop_tx = mpc52xx_psc_stop_tx,
.rx_clr_irq = mpc52xx_psc_rx_clr_irq,
.tx_clr_irq = mpc52xx_psc_tx_clr_irq,
.write_char = mpc52xx_psc_write_char,
.read_char = mpc52xx_psc_read_char,
.cw_disable_ints = mpc52xx_psc_cw_disable_ints,
.cw_restore_ints = mpc52xx_psc_cw_restore_ints,
.set_baudrate = mpc5200_psc_set_baudrate,
.get_irq = mpc52xx_psc_get_irq,
.handle_irq = mpc52xx_psc_handle_irq,
.get_status = mpc52xx_psc_get_status,
.get_ipcr = mpc52xx_psc_get_ipcr,
.command = mpc52xx_psc_command,
.set_mode = mpc52xx_psc_set_mode,
.set_rts = mpc52xx_psc_set_rts,
.enable_ms = mpc52xx_psc_enable_ms,
.set_sicr = mpc52xx_psc_set_sicr,
.set_imr = mpc52xx_psc_set_imr,
.get_mr1 = mpc52xx_psc_get_mr1,
};
static const struct psc_ops mpc5200b_psc_ops = {
.fifo_init = mpc52xx_psc_fifo_init,
.raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
.raw_tx_rdy = mpc52xx_psc_raw_tx_rdy,
.rx_rdy = mpc52xx_psc_rx_rdy,
.tx_rdy = mpc52xx_psc_tx_rdy,
.tx_empty = mpc52xx_psc_tx_empty,
.stop_rx = mpc52xx_psc_stop_rx,
.start_tx = mpc52xx_psc_start_tx,
.stop_tx = mpc52xx_psc_stop_tx,
.rx_clr_irq = mpc52xx_psc_rx_clr_irq,
.tx_clr_irq = mpc52xx_psc_tx_clr_irq,
.write_char = mpc52xx_psc_write_char,
.read_char = mpc52xx_psc_read_char,
.cw_disable_ints = mpc52xx_psc_cw_disable_ints,
.cw_restore_ints = mpc52xx_psc_cw_restore_ints,
.set_baudrate = mpc5200b_psc_set_baudrate,
.get_irq = mpc52xx_psc_get_irq,
.handle_irq = mpc52xx_psc_handle_irq,
.get_status = mpc52xx_psc_get_status,
.get_ipcr = mpc52xx_psc_get_ipcr,
.command = mpc52xx_psc_command,
.set_mode = mpc52xx_psc_set_mode,
.set_rts = mpc52xx_psc_set_rts,
.enable_ms = mpc52xx_psc_enable_ms,
.set_sicr = mpc52xx_psc_set_sicr,
.set_imr = mpc52xx_psc_set_imr,
.get_mr1 = mpc52xx_psc_get_mr1,
};
#endif /* CONFIG_PPC_MPC52xx */
#ifdef CONFIG_PPC_MPC512x
#define FIFO_512x(port) ((struct mpc512x_psc_fifo __iomem *)(PSC(port)+1))
/* PSC FIFO Controller for mpc512x */
struct psc_fifoc {
u32 fifoc_cmd;
u32 fifoc_int;
u32 fifoc_dma;
u32 fifoc_axe;
u32 fifoc_debug;
};
static struct psc_fifoc __iomem *psc_fifoc;
static unsigned int psc_fifoc_irq;
static struct clk *psc_fifoc_clk;
static void mpc512x_psc_fifo_init(struct uart_port *port)
{
/* /32 prescaler */
out_be16(&PSC(port)->mpc52xx_psc_clock_select, 0xdd00);
out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_RESET_SLICE);
out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
out_be32(&FIFO_512x(port)->txalarm, 1);
out_be32(&FIFO_512x(port)->tximr, 0);
out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_RESET_SLICE);
out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
out_be32(&FIFO_512x(port)->rxalarm, 1);
out_be32(&FIFO_512x(port)->rximr, 0);
out_be32(&FIFO_512x(port)->tximr, MPC512x_PSC_FIFO_ALARM);
out_be32(&FIFO_512x(port)->rximr, MPC512x_PSC_FIFO_ALARM);
}
static unsigned int mpc512x_psc_raw_rx_rdy(struct uart_port *port)
{
return !(in_be32(&FIFO_512x(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY);
}
static unsigned int mpc512x_psc_raw_tx_rdy(struct uart_port *port)
{
return !(in_be32(&FIFO_512x(port)->txsr) & MPC512x_PSC_FIFO_FULL);
}
static unsigned int mpc512x_psc_rx_rdy(struct uart_port *port)
{
return in_be32(&FIFO_512x(port)->rxsr)
& in_be32(&FIFO_512x(port)->rximr)
& MPC512x_PSC_FIFO_ALARM;
}
static unsigned int mpc512x_psc_tx_rdy(struct uart_port *port)
{
return in_be32(&FIFO_512x(port)->txsr)
& in_be32(&FIFO_512x(port)->tximr)
& MPC512x_PSC_FIFO_ALARM;
}
static unsigned int mpc512x_psc_tx_empty(struct uart_port *port)
{
return in_be32(&FIFO_512x(port)->txsr)
& MPC512x_PSC_FIFO_EMPTY;
}
static void mpc512x_psc_stop_rx(struct uart_port *port)
{
unsigned long rx_fifo_imr;
rx_fifo_imr = in_be32(&FIFO_512x(port)->rximr);
rx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
out_be32(&FIFO_512x(port)->rximr, rx_fifo_imr);
}
static void mpc512x_psc_start_tx(struct uart_port *port)
{
unsigned long tx_fifo_imr;
tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
tx_fifo_imr |= MPC512x_PSC_FIFO_ALARM;
out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
}
static void mpc512x_psc_stop_tx(struct uart_port *port)
{
unsigned long tx_fifo_imr;
tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
tx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
}
static void mpc512x_psc_rx_clr_irq(struct uart_port *port)
{
out_be32(&FIFO_512x(port)->rxisr, in_be32(&FIFO_512x(port)->rxisr));
}
static void mpc512x_psc_tx_clr_irq(struct uart_port *port)
{
out_be32(&FIFO_512x(port)->txisr, in_be32(&FIFO_512x(port)->txisr));
}
static void mpc512x_psc_write_char(struct uart_port *port, unsigned char c)
{
out_8(&FIFO_512x(port)->txdata_8, c);
}
static unsigned char mpc512x_psc_read_char(struct uart_port *port)
{
return in_8(&FIFO_512x(port)->rxdata_8);
}
static void mpc512x_psc_cw_disable_ints(struct uart_port *port)
{
port->read_status_mask =
in_be32(&FIFO_512x(port)->tximr) << 16 |
in_be32(&FIFO_512x(port)->rximr);
out_be32(&FIFO_512x(port)->tximr, 0);
out_be32(&FIFO_512x(port)->rximr, 0);
}
static void mpc512x_psc_cw_restore_ints(struct uart_port *port)
{
out_be32(&FIFO_512x(port)->tximr,
(port->read_status_mask >> 16) & 0x7f);
out_be32(&FIFO_512x(port)->rximr, port->read_status_mask & 0x7f);
}
static unsigned int mpc512x_psc_set_baudrate(struct uart_port *port,
struct ktermios *new,
struct ktermios *old)
{
unsigned int baud;
unsigned int divisor;
/*
* The "MPC5121e Microcontroller Reference Manual, Rev. 3" says on
* pg. 30-10 that the chip supports a /32 and a /10 prescaler.
* Furthermore, it states that "After reset, the prescaler by 10
* for the UART mode is selected", but the reset register value is
* 0x0000 which means a /32 prescaler. This is wrong.
*
* In reality using /32 prescaler doesn't work, as it is not supported!
* Use /16 or /10 prescaler, see "MPC5121e Hardware Design Guide",
* Chapter 4.1 PSC in UART Mode.
* Calculate with a /16 prescaler here.
*/
/* uartclk contains the ips freq */
baud = uart_get_baud_rate(port, new, old,
port->uartclk / (16 * 0xffff) + 1,
port->uartclk / 16);
divisor = (port->uartclk + 8 * baud) / (16 * baud);
/* enable the /16 prescaler and set the divisor */
mpc52xx_set_divisor(PSC(port), 0xdd00, divisor);
return baud;
}
/* Init PSC FIFO Controller */
static int __init mpc512x_psc_fifoc_init(void)
{
int err;
struct device_node *np;
struct clk *clk;
/* default error code, potentially overwritten by clock calls */
err = -ENODEV;
np = of_find_compatible_node(NULL, NULL,
"fsl,mpc5121-psc-fifo");
if (!np) {
pr_err("%s: Can't find FIFOC node\n", __func__);
goto out_err;
}
clk = of_clk_get(np, 0);
if (IS_ERR(clk)) {
/* backwards compat with device trees that lack clock specs */
clk = clk_get_sys(np->name, "ipg");
}
if (IS_ERR(clk)) {
pr_err("%s: Can't lookup FIFO clock\n", __func__);
err = PTR_ERR(clk);
goto out_ofnode_put;
}
if (clk_prepare_enable(clk)) {
pr_err("%s: Can't enable FIFO clock\n", __func__);
clk_put(clk);
goto out_ofnode_put;
}
psc_fifoc_clk = clk;
psc_fifoc = of_iomap(np, 0);
if (!psc_fifoc) {
pr_err("%s: Can't map FIFOC\n", __func__);
goto out_clk_disable;
}
psc_fifoc_irq = irq_of_parse_and_map(np, 0);
if (psc_fifoc_irq == 0) {
pr_err("%s: Can't get FIFOC irq\n", __func__);
goto out_unmap;
}
of_node_put(np);
return 0;
out_unmap:
iounmap(psc_fifoc);
out_clk_disable:
clk_disable_unprepare(psc_fifoc_clk);
clk_put(psc_fifoc_clk);
out_ofnode_put:
of_node_put(np);
out_err:
return err;
}
static void __exit mpc512x_psc_fifoc_uninit(void)
{
iounmap(psc_fifoc);
/* disable the clock, errors are not fatal */
if (psc_fifoc_clk) {
clk_disable_unprepare(psc_fifoc_clk);
clk_put(psc_fifoc_clk);
psc_fifoc_clk = NULL;
}
}
/* 512x specific interrupt handler. The caller holds the port lock */
static irqreturn_t mpc512x_psc_handle_irq(struct uart_port *port)
{
unsigned long fifoc_int;
int psc_num;
/* Read pending PSC FIFOC interrupts */
fifoc_int = in_be32(&psc_fifoc->fifoc_int);
/* Check if it is an interrupt for this port */
psc_num = (port->mapbase & 0xf00) >> 8;
if (test_bit(psc_num, &fifoc_int) ||
test_bit(psc_num + 16, &fifoc_int))
return mpc5xxx_uart_process_int(port);
return IRQ_NONE;
}
static struct clk *psc_mclk_clk[MPC52xx_PSC_MAXNUM];
static struct clk *psc_ipg_clk[MPC52xx_PSC_MAXNUM];
/* called from within the .request_port() callback (allocation) */
static int mpc512x_psc_alloc_clock(struct uart_port *port)
{
int psc_num;
struct clk *clk;
int err;
psc_num = (port->mapbase & 0xf00) >> 8;
clk = devm_clk_get(port->dev, "mclk");
if (IS_ERR(clk)) {
dev_err(port->dev, "Failed to get MCLK!\n");
err = PTR_ERR(clk);
goto out_err;
}
err = clk_prepare_enable(clk);
if (err) {
dev_err(port->dev, "Failed to enable MCLK!\n");
goto out_err;
}
psc_mclk_clk[psc_num] = clk;
clk = devm_clk_get(port->dev, "ipg");
if (IS_ERR(clk)) {
dev_err(port->dev, "Failed to get IPG clock!\n");
err = PTR_ERR(clk);
goto out_err;
}
err = clk_prepare_enable(clk);
if (err) {
dev_err(port->dev, "Failed to enable IPG clock!\n");
goto out_err;
}
psc_ipg_clk[psc_num] = clk;
return 0;
out_err:
if (psc_mclk_clk[psc_num]) {
clk_disable_unprepare(psc_mclk_clk[psc_num]);
psc_mclk_clk[psc_num] = NULL;
}
if (psc_ipg_clk[psc_num]) {
clk_disable_unprepare(psc_ipg_clk[psc_num]);
psc_ipg_clk[psc_num] = NULL;
}
return err;
}
/* called from within the .release_port() callback (release) */
static void mpc512x_psc_relse_clock(struct uart_port *port)
{
int psc_num;
struct clk *clk;
psc_num = (port->mapbase & 0xf00) >> 8;
clk = psc_mclk_clk[psc_num];
if (clk) {
clk_disable_unprepare(clk);
psc_mclk_clk[psc_num] = NULL;
}
if (psc_ipg_clk[psc_num]) {
clk_disable_unprepare(psc_ipg_clk[psc_num]);
psc_ipg_clk[psc_num] = NULL;
}
}
/* implementation of the .clock() callback (enable/disable) */
static int mpc512x_psc_endis_clock(struct uart_port *port, int enable)
{
int psc_num;
struct clk *psc_clk;
int ret;
if (uart_console(port))
return 0;
psc_num = (port->mapbase & 0xf00) >> 8;
psc_clk = psc_mclk_clk[psc_num];
if (!psc_clk) {
dev_err(port->dev, "Failed to get PSC clock entry!\n");
return -ENODEV;
}
dev_dbg(port->dev, "mclk %sable\n", enable ? "en" : "dis");
if (enable) {
ret = clk_enable(psc_clk);
if (ret)
dev_err(port->dev, "Failed to enable MCLK!\n");
return ret;
} else {
clk_disable(psc_clk);
return 0;
}
}
static void mpc512x_psc_get_irq(struct uart_port *port, struct device_node *np)
{
port->irqflags = IRQF_SHARED;
port->irq = psc_fifoc_irq;
}
#endif
#ifdef CONFIG_PPC_MPC512x
#define PSC_5125(port) ((struct mpc5125_psc __iomem *)((port)->membase))
#define FIFO_5125(port) ((struct mpc512x_psc_fifo __iomem *)(PSC_5125(port)+1))
static void mpc5125_psc_fifo_init(struct uart_port *port)
{
/* /32 prescaler */
out_8(&PSC_5125(port)->mpc52xx_psc_clock_select, 0xdd);
out_be32(&FIFO_5125(port)->txcmd, MPC512x_PSC_FIFO_RESET_SLICE);
out_be32(&FIFO_5125(port)->txcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
out_be32(&FIFO_5125(port)->txalarm, 1);
out_be32(&FIFO_5125(port)->tximr, 0);
out_be32(&FIFO_5125(port)->rxcmd, MPC512x_PSC_FIFO_RESET_SLICE);
out_be32(&FIFO_5125(port)->rxcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
out_be32(&FIFO_5125(port)->rxalarm, 1);
out_be32(&FIFO_5125(port)->rximr, 0);
out_be32(&FIFO_5125(port)->tximr, MPC512x_PSC_FIFO_ALARM);
out_be32(&FIFO_5125(port)->rximr, MPC512x_PSC_FIFO_ALARM);
}
static unsigned int mpc5125_psc_raw_rx_rdy(struct uart_port *port)
{
return !(in_be32(&FIFO_5125(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY);
}
static unsigned int mpc5125_psc_raw_tx_rdy(struct uart_port *port)
{
return !(in_be32(&FIFO_5125(port)->txsr) & MPC512x_PSC_FIFO_FULL);
}
static unsigned int mpc5125_psc_rx_rdy(struct uart_port *port)
{
return in_be32(&FIFO_5125(port)->rxsr) &
in_be32(&FIFO_5125(port)->rximr) & MPC512x_PSC_FIFO_ALARM;
}
static unsigned int mpc5125_psc_tx_rdy(struct uart_port *port)
{
return in_be32(&FIFO_5125(port)->txsr) &
in_be32(&FIFO_5125(port)->tximr) & MPC512x_PSC_FIFO_ALARM;
}
static unsigned int mpc5125_psc_tx_empty(struct uart_port *port)
{
return in_be32(&FIFO_5125(port)->txsr) & MPC512x_PSC_FIFO_EMPTY;
}
static void mpc5125_psc_stop_rx(struct uart_port *port)
{
unsigned long rx_fifo_imr;
rx_fifo_imr = in_be32(&FIFO_5125(port)->rximr);
rx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
out_be32(&FIFO_5125(port)->rximr, rx_fifo_imr);
}
static void mpc5125_psc_start_tx(struct uart_port *port)
{
unsigned long tx_fifo_imr;
tx_fifo_imr = in_be32(&FIFO_5125(port)->tximr);
tx_fifo_imr |= MPC512x_PSC_FIFO_ALARM;
out_be32(&FIFO_5125(port)->tximr, tx_fifo_imr);
}
static void mpc5125_psc_stop_tx(struct uart_port *port)
{
unsigned long tx_fifo_imr;
tx_fifo_imr = in_be32(&FIFO_5125(port)->tximr);
tx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
out_be32(&FIFO_5125(port)->tximr, tx_fifo_imr);
}
static void mpc5125_psc_rx_clr_irq(struct uart_port *port)
{
out_be32(&FIFO_5125(port)->rxisr, in_be32(&FIFO_5125(port)->rxisr));
}
static void mpc5125_psc_tx_clr_irq(struct uart_port *port)
{
out_be32(&FIFO_5125(port)->txisr, in_be32(&FIFO_5125(port)->txisr));
}
static void mpc5125_psc_write_char(struct uart_port *port, unsigned char c)
{
out_8(&FIFO_5125(port)->txdata_8, c);
}
static unsigned char mpc5125_psc_read_char(struct uart_port *port)
{
return in_8(&FIFO_5125(port)->rxdata_8);
}
static void mpc5125_psc_cw_disable_ints(struct uart_port *port)
{
port->read_status_mask =
in_be32(&FIFO_5125(port)->tximr) << 16 |
in_be32(&FIFO_5125(port)->rximr);
out_be32(&FIFO_5125(port)->tximr, 0);
out_be32(&FIFO_5125(port)->rximr, 0);
}
static void mpc5125_psc_cw_restore_ints(struct uart_port *port)
{
out_be32(&FIFO_5125(port)->tximr,
(port->read_status_mask >> 16) & 0x7f);
out_be32(&FIFO_5125(port)->rximr, port->read_status_mask & 0x7f);
}
static inline void mpc5125_set_divisor(struct mpc5125_psc __iomem *psc,
u8 prescaler, unsigned int divisor)
{
/* select prescaler */
out_8(&psc->mpc52xx_psc_clock_select, prescaler);
out_8(&psc->ctur, divisor >> 8);
out_8(&psc->ctlr, divisor & 0xff);
}
static unsigned int mpc5125_psc_set_baudrate(struct uart_port *port,
struct ktermios *new,
struct ktermios *old)
{
unsigned int baud;
unsigned int divisor;
/*
* Calculate with a /16 prescaler here.
*/
/* uartclk contains the ips freq */
baud = uart_get_baud_rate(port, new, old,
port->uartclk / (16 * 0xffff) + 1,
port->uartclk / 16);
divisor = (port->uartclk + 8 * baud) / (16 * baud);
/* enable the /16 prescaler and set the divisor */
mpc5125_set_divisor(PSC_5125(port), 0xdd, divisor);
return baud;
}
/*
* MPC5125 have compatible PSC FIFO Controller.
* Special init not needed.
*/
static u16 mpc5125_psc_get_status(struct uart_port *port)
{
return in_be16(&PSC_5125(port)->mpc52xx_psc_status);
}
static u8 mpc5125_psc_get_ipcr(struct uart_port *port)
{
return in_8(&PSC_5125(port)->mpc52xx_psc_ipcr);
}
static void mpc5125_psc_command(struct uart_port *port, u8 cmd)
{
out_8(&PSC_5125(port)->command, cmd);
}
static void mpc5125_psc_set_mode(struct uart_port *port, u8 mr1, u8 mr2)
{
out_8(&PSC_5125(port)->mr1, mr1);
out_8(&PSC_5125(port)->mr2, mr2);
}
static void mpc5125_psc_set_rts(struct uart_port *port, int state)
{
if (state & TIOCM_RTS)
out_8(&PSC_5125(port)->op1, MPC52xx_PSC_OP_RTS);
else
out_8(&PSC_5125(port)->op0, MPC52xx_PSC_OP_RTS);
}
static void mpc5125_psc_enable_ms(struct uart_port *port)
{
struct mpc5125_psc __iomem *psc = PSC_5125(port);
/* clear D_*-bits by reading them */
in_8(&psc->mpc52xx_psc_ipcr);
/* enable CTS and DCD as IPC interrupts */
out_8(&psc->mpc52xx_psc_acr, MPC52xx_PSC_IEC_CTS | MPC52xx_PSC_IEC_DCD);
port->read_status_mask |= MPC52xx_PSC_IMR_IPC;
out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
}
static void mpc5125_psc_set_sicr(struct uart_port *port, u32 val)
{
out_be32(&PSC_5125(port)->sicr, val);
}
static void mpc5125_psc_set_imr(struct uart_port *port, u16 val)
{
out_be16(&PSC_5125(port)->mpc52xx_psc_imr, val);
}
static u8 mpc5125_psc_get_mr1(struct uart_port *port)
{
return in_8(&PSC_5125(port)->mr1);
}
static const struct psc_ops mpc5125_psc_ops = {
.fifo_init = mpc5125_psc_fifo_init,
.raw_rx_rdy = mpc5125_psc_raw_rx_rdy,
.raw_tx_rdy = mpc5125_psc_raw_tx_rdy,
.rx_rdy = mpc5125_psc_rx_rdy,
.tx_rdy = mpc5125_psc_tx_rdy,
.tx_empty = mpc5125_psc_tx_empty,
.stop_rx = mpc5125_psc_stop_rx,
.start_tx = mpc5125_psc_start_tx,
.stop_tx = mpc5125_psc_stop_tx,
.rx_clr_irq = mpc5125_psc_rx_clr_irq,
.tx_clr_irq = mpc5125_psc_tx_clr_irq,
.write_char = mpc5125_psc_write_char,
.read_char = mpc5125_psc_read_char,
.cw_disable_ints = mpc5125_psc_cw_disable_ints,
.cw_restore_ints = mpc5125_psc_cw_restore_ints,
.set_baudrate = mpc5125_psc_set_baudrate,
.clock_alloc = mpc512x_psc_alloc_clock,
.clock_relse = mpc512x_psc_relse_clock,
.clock = mpc512x_psc_endis_clock,
.fifoc_init = mpc512x_psc_fifoc_init,
.fifoc_uninit = mpc512x_psc_fifoc_uninit,
.get_irq = mpc512x_psc_get_irq,
.handle_irq = mpc512x_psc_handle_irq,
.get_status = mpc5125_psc_get_status,
.get_ipcr = mpc5125_psc_get_ipcr,
.command = mpc5125_psc_command,
.set_mode = mpc5125_psc_set_mode,
.set_rts = mpc5125_psc_set_rts,
.enable_ms = mpc5125_psc_enable_ms,
.set_sicr = mpc5125_psc_set_sicr,
.set_imr = mpc5125_psc_set_imr,
.get_mr1 = mpc5125_psc_get_mr1,
};
static const struct psc_ops mpc512x_psc_ops = {
.fifo_init = mpc512x_psc_fifo_init,
.raw_rx_rdy = mpc512x_psc_raw_rx_rdy,
.raw_tx_rdy = mpc512x_psc_raw_tx_rdy,
.rx_rdy = mpc512x_psc_rx_rdy,
.tx_rdy = mpc512x_psc_tx_rdy,
.tx_empty = mpc512x_psc_tx_empty,
.stop_rx = mpc512x_psc_stop_rx,
.start_tx = mpc512x_psc_start_tx,
.stop_tx = mpc512x_psc_stop_tx,
.rx_clr_irq = mpc512x_psc_rx_clr_irq,
.tx_clr_irq = mpc512x_psc_tx_clr_irq,
.write_char = mpc512x_psc_write_char,
.read_char = mpc512x_psc_read_char,
.cw_disable_ints = mpc512x_psc_cw_disable_ints,
.cw_restore_ints = mpc512x_psc_cw_restore_ints,
.set_baudrate = mpc512x_psc_set_baudrate,
.clock_alloc = mpc512x_psc_alloc_clock,
.clock_relse = mpc512x_psc_relse_clock,
.clock = mpc512x_psc_endis_clock,
.fifoc_init = mpc512x_psc_fifoc_init,
.fifoc_uninit = mpc512x_psc_fifoc_uninit,
.get_irq = mpc512x_psc_get_irq,
.handle_irq = mpc512x_psc_handle_irq,
.get_status = mpc52xx_psc_get_status,
.get_ipcr = mpc52xx_psc_get_ipcr,
.command = mpc52xx_psc_command,
.set_mode = mpc52xx_psc_set_mode,
.set_rts = mpc52xx_psc_set_rts,
.enable_ms = mpc52xx_psc_enable_ms,
.set_sicr = mpc52xx_psc_set_sicr,
.set_imr = mpc52xx_psc_set_imr,
.get_mr1 = mpc52xx_psc_get_mr1,
};
#endif /* CONFIG_PPC_MPC512x */
static const struct psc_ops *psc_ops;
/* ======================================================================== */
/* UART operations */
/* ======================================================================== */
static unsigned int
mpc52xx_uart_tx_empty(struct uart_port *port)
{
return psc_ops->tx_empty(port) ? TIOCSER_TEMT : 0;
}
static void
mpc52xx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
psc_ops->set_rts(port, mctrl & TIOCM_RTS);
}
static unsigned int
mpc52xx_uart_get_mctrl(struct uart_port *port)
{
unsigned int ret = TIOCM_DSR;
u8 status = psc_ops->get_ipcr(port);
if (!(status & MPC52xx_PSC_CTS))
ret |= TIOCM_CTS;
if (!(status & MPC52xx_PSC_DCD))
ret |= TIOCM_CAR;
return ret;
}
static void
mpc52xx_uart_stop_tx(struct uart_port *port)
{
/* port->lock taken by caller */
psc_ops->stop_tx(port);
}
static void
mpc52xx_uart_start_tx(struct uart_port *port)
{
/* port->lock taken by caller */
psc_ops->start_tx(port);
}
static void
mpc52xx_uart_stop_rx(struct uart_port *port)
{
/* port->lock taken by caller */
psc_ops->stop_rx(port);
}
static void
mpc52xx_uart_enable_ms(struct uart_port *port)
{
psc_ops->enable_ms(port);
}
static void
mpc52xx_uart_break_ctl(struct uart_port *port, int ctl)
{
unsigned long flags;
spin_lock_irqsave(&port->lock, flags);
if (ctl == -1)
psc_ops->command(port, MPC52xx_PSC_START_BRK);
else
psc_ops->command(port, MPC52xx_PSC_STOP_BRK);
spin_unlock_irqrestore(&port->lock, flags);
}
static int
mpc52xx_uart_startup(struct uart_port *port)
{
int ret;
if (psc_ops->clock) {
ret = psc_ops->clock(port, 1);
if (ret)
return ret;
}
/* Request IRQ */
ret = request_irq(port->irq, mpc52xx_uart_int,
port->irqflags, "mpc52xx_psc_uart", port);
if (ret)
return ret;
/* Reset/activate the port, clear and enable interrupts */
psc_ops->command(port, MPC52xx_PSC_RST_RX);
psc_ops->command(port, MPC52xx_PSC_RST_TX);
/*
* According to Freescale's support the RST_TX command can produce a
* spike on the TX pin. So they recommend to delay "for one character".
* One millisecond should be enough for everyone.
*/
msleep(1);
psc_ops->set_sicr(port, 0); /* UART mode DCD ignored */
psc_ops->fifo_init(port);
psc_ops->command(port, MPC52xx_PSC_TX_ENABLE);
psc_ops->command(port, MPC52xx_PSC_RX_ENABLE);
return 0;
}
static void
mpc52xx_uart_shutdown(struct uart_port *port)
{
/* Shut down the port. Leave TX active if on a console port */
psc_ops->command(port, MPC52xx_PSC_RST_RX);
if (!uart_console(port))
psc_ops->command(port, MPC52xx_PSC_RST_TX);
port->read_status_mask = 0;
psc_ops->set_imr(port, port->read_status_mask);
if (psc_ops->clock)
psc_ops->clock(port, 0);
/* Disable interrupt */
psc_ops->cw_disable_ints(port);
/* Release interrupt */
free_irq(port->irq, port);
}
static void
mpc52xx_uart_set_termios(struct uart_port *port, struct ktermios *new,
struct ktermios *old)
{
unsigned long flags;
unsigned char mr1, mr2;
unsigned int j;
unsigned int baud;
/* Prepare what we're gonna write */
mr1 = 0;
switch (new->c_cflag & CSIZE) {
case CS5: mr1 |= MPC52xx_PSC_MODE_5_BITS;
break;
case CS6: mr1 |= MPC52xx_PSC_MODE_6_BITS;
break;
case CS7: mr1 |= MPC52xx_PSC_MODE_7_BITS;
break;
case CS8:
default: mr1 |= MPC52xx_PSC_MODE_8_BITS;
}
if (new->c_cflag & PARENB) {
if (new->c_cflag & CMSPAR)
mr1 |= MPC52xx_PSC_MODE_PARFORCE;
/* With CMSPAR, PARODD also means high parity (same as termios) */
mr1 |= (new->c_cflag & PARODD) ?
MPC52xx_PSC_MODE_PARODD : MPC52xx_PSC_MODE_PAREVEN;
} else {
mr1 |= MPC52xx_PSC_MODE_PARNONE;
}
mr2 = 0;
if (new->c_cflag & CSTOPB)
mr2 |= MPC52xx_PSC_MODE_TWO_STOP;
else
mr2 |= ((new->c_cflag & CSIZE) == CS5) ?
MPC52xx_PSC_MODE_ONE_STOP_5_BITS :
MPC52xx_PSC_MODE_ONE_STOP;
if (new->c_cflag & CRTSCTS) {
mr1 |= MPC52xx_PSC_MODE_RXRTS;
mr2 |= MPC52xx_PSC_MODE_TXCTS;
}
/* Get the lock */
spin_lock_irqsave(&port->lock, flags);
/* Do our best to flush TX & RX, so we don't lose anything */
/* But we don't wait indefinitely ! */
j = 5000000; /* Maximum wait */
/* FIXME Can't receive chars since set_termios might be called at early
* boot for the console, all stuff is not yet ready to receive at that
* time and that just makes the kernel oops */
/* while (j-- && mpc52xx_uart_int_rx_chars(port)); */
while (!mpc52xx_uart_tx_empty(port) && --j)
udelay(1);
if (!j)
printk(KERN_ERR "mpc52xx_uart.c: "
"Unable to flush RX & TX fifos in-time in set_termios."
"Some chars may have been lost.\n");
/* Reset the TX & RX */
psc_ops->command(port, MPC52xx_PSC_RST_RX);
psc_ops->command(port, MPC52xx_PSC_RST_TX);
/* Send new mode settings */
psc_ops->set_mode(port, mr1, mr2);
baud = psc_ops->set_baudrate(port, new, old);
/* Update the per-port timeout */
uart_update_timeout(port, new->c_cflag, baud);
if (UART_ENABLE_MS(port, new->c_cflag))
mpc52xx_uart_enable_ms(port);
/* Reenable TX & RX */
psc_ops->command(port, MPC52xx_PSC_TX_ENABLE);
psc_ops->command(port, MPC52xx_PSC_RX_ENABLE);
/* We're all set, release the lock */
spin_unlock_irqrestore(&port->lock, flags);
}
static const char *
mpc52xx_uart_type(struct uart_port *port)
{
/*
* We keep using PORT_MPC52xx for historic reasons although it applies
* for MPC512x, too, but print "MPC5xxx" to not irritate users
*/
return port->type == PORT_MPC52xx ? "MPC5xxx PSC" : NULL;
}
static void
mpc52xx_uart_release_port(struct uart_port *port)
{
if (psc_ops->clock_relse)
psc_ops->clock_relse(port);
/* remapped by us ? */
if (port->flags & UPF_IOREMAP) {
iounmap(port->membase);
port->membase = NULL;
}
release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc));
}
static int
mpc52xx_uart_request_port(struct uart_port *port)
{
int err;
if (port->flags & UPF_IOREMAP) /* Need to remap ? */
port->membase = ioremap(port->mapbase,
sizeof(struct mpc52xx_psc));
if (!port->membase)
return -EINVAL;
err = request_mem_region(port->mapbase, sizeof(struct mpc52xx_psc),
"mpc52xx_psc_uart") != NULL ? 0 : -EBUSY;
if (err)
goto out_membase;
if (psc_ops->clock_alloc) {
err = psc_ops->clock_alloc(port);
if (err)
goto out_mapregion;
}
return 0;
out_mapregion:
release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc));
out_membase:
if (port->flags & UPF_IOREMAP) {
iounmap(port->membase);
port->membase = NULL;
}
return err;
}
static void
mpc52xx_uart_config_port(struct uart_port *port, int flags)
{
if ((flags & UART_CONFIG_TYPE)
&& (mpc52xx_uart_request_port(port) == 0))
port->type = PORT_MPC52xx;
}
static int
mpc52xx_uart_verify_port(struct uart_port *port, struct serial_struct *ser)
{
if (ser->type != PORT_UNKNOWN && ser->type != PORT_MPC52xx)
return -EINVAL;
if ((ser->irq != port->irq) ||
(ser->io_type != UPIO_MEM) ||
(ser->baud_base != port->uartclk) ||
(ser->iomem_base != (void *)port->mapbase) ||
(ser->hub6 != 0))
return -EINVAL;
return 0;
}
static const struct uart_ops mpc52xx_uart_ops = {
.tx_empty = mpc52xx_uart_tx_empty,
.set_mctrl = mpc52xx_uart_set_mctrl,
.get_mctrl = mpc52xx_uart_get_mctrl,
.stop_tx = mpc52xx_uart_stop_tx,
.start_tx = mpc52xx_uart_start_tx,
.stop_rx = mpc52xx_uart_stop_rx,
.enable_ms = mpc52xx_uart_enable_ms,
.break_ctl = mpc52xx_uart_break_ctl,
.startup = mpc52xx_uart_startup,
.shutdown = mpc52xx_uart_shutdown,
.set_termios = mpc52xx_uart_set_termios,
/* .pm = mpc52xx_uart_pm, Not supported yet */
.type = mpc52xx_uart_type,
.release_port = mpc52xx_uart_release_port,
.request_port = mpc52xx_uart_request_port,
.config_port = mpc52xx_uart_config_port,
.verify_port = mpc52xx_uart_verify_port
};
/* ======================================================================== */
/* Interrupt handling */
/* ======================================================================== */
static inline unsigned int
mpc52xx_uart_int_rx_chars(struct uart_port *port)
{
struct tty_port *tport = &port->state->port;
unsigned char ch, flag;
unsigned short status;
/* While we can read, do so ! */
while (psc_ops->raw_rx_rdy(port)) {
/* Get the char */
ch = psc_ops->read_char(port);
/* Handle sysreq char */
if (uart_handle_sysrq_char(port, ch))
continue;
/* Store it */
flag = TTY_NORMAL;
port->icount.rx++;
status = psc_ops->get_status(port);
if (status & (MPC52xx_PSC_SR_PE |
MPC52xx_PSC_SR_FE |
MPC52xx_PSC_SR_RB)) {
if (status & MPC52xx_PSC_SR_RB) {
flag = TTY_BREAK;
uart_handle_break(port);
port->icount.brk++;
} else if (status & MPC52xx_PSC_SR_PE) {
flag = TTY_PARITY;
port->icount.parity++;
}
else if (status & MPC52xx_PSC_SR_FE) {
flag = TTY_FRAME;
port->icount.frame++;
}
/* Clear error condition */
psc_ops->command(port, MPC52xx_PSC_RST_ERR_STAT);
}
tty_insert_flip_char(tport, ch, flag);
if (status & MPC52xx_PSC_SR_OE) {
/*
* Overrun is special, since it's
* reported immediately, and doesn't
* affect the current character
*/
tty_insert_flip_char(tport, 0, TTY_OVERRUN);
port->icount.overrun++;
}
}
tty_flip_buffer_push(tport);
return psc_ops->raw_rx_rdy(port);
}
static inline int
mpc52xx_uart_int_tx_chars(struct uart_port *port)
{
struct circ_buf *xmit = &port->state->xmit;
/* Process out of band chars */
if (port->x_char) {
psc_ops->write_char(port, port->x_char);
port->icount.tx++;
port->x_char = 0;
return 1;
}
/* Nothing to do ? */
if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
mpc52xx_uart_stop_tx(port);
return 0;
}
/* Send chars */
while (psc_ops->raw_tx_rdy(port)) {
psc_ops->write_char(port, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
if (uart_circ_empty(xmit))
break;
}
/* Wake up */
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
/* Maybe we're done after all */
if (uart_circ_empty(xmit)) {
mpc52xx_uart_stop_tx(port);
return 0;
}
return 1;
}
static irqreturn_t
mpc5xxx_uart_process_int(struct uart_port *port)
{
unsigned long pass = ISR_PASS_LIMIT;
unsigned int keepgoing;
u8 status;
/* While we have stuff to do, we continue */
do {
/* If we don't find anything to do, we stop */
keepgoing = 0;
psc_ops->rx_clr_irq(port);
if (psc_ops->rx_rdy(port))
keepgoing |= mpc52xx_uart_int_rx_chars(port);
psc_ops->tx_clr_irq(port);
if (psc_ops->tx_rdy(port))
keepgoing |= mpc52xx_uart_int_tx_chars(port);
status = psc_ops->get_ipcr(port);
if (status & MPC52xx_PSC_D_DCD)
uart_handle_dcd_change(port, !(status & MPC52xx_PSC_DCD));
if (status & MPC52xx_PSC_D_CTS)
uart_handle_cts_change(port, !(status & MPC52xx_PSC_CTS));
/* Limit number of iteration */
if (!(--pass))
keepgoing = 0;
} while (keepgoing);
return IRQ_HANDLED;
}
static irqreturn_t
mpc52xx_uart_int(int irq, void *dev_id)
{
struct uart_port *port = dev_id;
irqreturn_t ret;
spin_lock(&port->lock);
ret = psc_ops->handle_irq(port);
spin_unlock(&port->lock);
return ret;
}
/* ======================================================================== */
/* Console ( if applicable ) */
/* ======================================================================== */
#ifdef CONFIG_SERIAL_MPC52xx_CONSOLE
static void __init
mpc52xx_console_get_options(struct uart_port *port,
int *baud, int *parity, int *bits, int *flow)
{
unsigned char mr1;
pr_debug("mpc52xx_console_get_options(port=%p)\n", port);
/* Read the mode registers */
mr1 = psc_ops->get_mr1(port);
/* CT{U,L}R are write-only ! */
*baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
/* Parse them */
switch (mr1 & MPC52xx_PSC_MODE_BITS_MASK) {
case MPC52xx_PSC_MODE_5_BITS:
*bits = 5;
break;
case MPC52xx_PSC_MODE_6_BITS:
*bits = 6;
break;
case MPC52xx_PSC_MODE_7_BITS:
*bits = 7;
break;
case MPC52xx_PSC_MODE_8_BITS:
default:
*bits = 8;
}
if (mr1 & MPC52xx_PSC_MODE_PARNONE)
*parity = 'n';
else
*parity = mr1 & MPC52xx_PSC_MODE_PARODD ? 'o' : 'e';
}
static void
mpc52xx_console_write(struct console *co, const char *s, unsigned int count)
{
struct uart_port *port = &mpc52xx_uart_ports[co->index];
unsigned int i, j;
/* Disable interrupts */
psc_ops->cw_disable_ints(port);
/* Wait the TX buffer to be empty */
j = 5000000; /* Maximum wait */
while (!mpc52xx_uart_tx_empty(port) && --j)
udelay(1);
/* Write all the chars */
for (i = 0; i < count; i++, s++) {
/* Line return handling */
if (*s == '\n')
psc_ops->write_char(port, '\r');
/* Send the char */
psc_ops->write_char(port, *s);
/* Wait the TX buffer to be empty */
j = 20000; /* Maximum wait */
while (!mpc52xx_uart_tx_empty(port) && --j)
udelay(1);
}
/* Restore interrupt state */
psc_ops->cw_restore_ints(port);
}
static int __init
mpc52xx_console_setup(struct console *co, char *options)
{
struct uart_port *port = &mpc52xx_uart_ports[co->index];
struct device_node *np = mpc52xx_uart_nodes[co->index];
unsigned int uartclk;
struct resource res;
int ret;
int baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
int bits = 8;
int parity = 'n';
int flow = 'n';
pr_debug("mpc52xx_console_setup co=%p, co->index=%i, options=%s\n",
co, co->index, options);
if ((co->index < 0) || (co->index >= MPC52xx_PSC_MAXNUM)) {
pr_debug("PSC%x out of range\n", co->index);
return -EINVAL;
}
if (!np) {
pr_debug("PSC%x not found in device tree\n", co->index);
return -EINVAL;
}
pr_debug("Console on ttyPSC%x is %pOF\n",
co->index, mpc52xx_uart_nodes[co->index]);
/* Fetch register locations */
ret = of_address_to_resource(np, 0, &res);
if (ret) {
pr_debug("Could not get resources for PSC%x\n", co->index);
return ret;
}
uartclk = mpc5xxx_get_bus_frequency(np);
if (uartclk == 0) {
pr_debug("Could not find uart clock frequency!\n");
return -EINVAL;
}
/* Basic port init. Needed since we use some uart_??? func before
* real init for early access */
spin_lock_init(&port->lock);
port->uartclk = uartclk;
port->ops = &mpc52xx_uart_ops;
port->mapbase = res.start;
port->membase = ioremap(res.start, sizeof(struct mpc52xx_psc));
port->irq = irq_of_parse_and_map(np, 0);
if (port->membase == NULL)
return -EINVAL;
pr_debug("mpc52xx-psc uart at %p, mapped to %p, irq=%x, freq=%i\n",
(void *)port->mapbase, port->membase,
port->irq, port->uartclk);
/* Setup the port parameters accoding to options */
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
mpc52xx_console_get_options(port, &baud, &parity, &bits, &flow);
pr_debug("Setting console parameters: %i %i%c1 flow=%c\n",
baud, bits, parity, flow);
return uart_set_options(port, co, baud, parity, bits, flow);
}
static struct uart_driver mpc52xx_uart_driver;
static struct console mpc52xx_console = {
.name = "ttyPSC",
.write = mpc52xx_console_write,
.device = uart_console_device,
.setup = mpc52xx_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1, /* Specified on the cmdline (e.g. console=ttyPSC0) */
.data = &mpc52xx_uart_driver,
};
static int __init
mpc52xx_console_init(void)
{
mpc52xx_uart_of_enumerate();
register_console(&mpc52xx_console);
return 0;
}
console_initcall(mpc52xx_console_init);
#define MPC52xx_PSC_CONSOLE &mpc52xx_console
#else
#define MPC52xx_PSC_CONSOLE NULL
#endif
/* ======================================================================== */
/* UART Driver */
/* ======================================================================== */
static struct uart_driver mpc52xx_uart_driver = {
.driver_name = "mpc52xx_psc_uart",
.dev_name = "ttyPSC",
.major = SERIAL_PSC_MAJOR,
.minor = SERIAL_PSC_MINOR,
.nr = MPC52xx_PSC_MAXNUM,
.cons = MPC52xx_PSC_CONSOLE,
};
/* ======================================================================== */
/* OF Platform Driver */
/* ======================================================================== */
static const struct of_device_id mpc52xx_uart_of_match[] = {
#ifdef CONFIG_PPC_MPC52xx
{ .compatible = "fsl,mpc5200b-psc-uart", .data = &mpc5200b_psc_ops, },
{ .compatible = "fsl,mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
/* binding used by old lite5200 device trees: */
{ .compatible = "mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
/* binding used by efika: */
{ .compatible = "mpc5200-serial", .data = &mpc52xx_psc_ops, },
#endif
#ifdef CONFIG_PPC_MPC512x
{ .compatible = "fsl,mpc5121-psc-uart", .data = &mpc512x_psc_ops, },
{ .compatible = "fsl,mpc5125-psc-uart", .data = &mpc5125_psc_ops, },
#endif
{},
};
static int mpc52xx_uart_of_probe(struct platform_device *op)
{
int idx = -1;
unsigned int uartclk;
struct uart_port *port = NULL;
struct resource res;
int ret;
/* Check validity & presence */
for (idx = 0; idx < MPC52xx_PSC_MAXNUM; idx++)
if (mpc52xx_uart_nodes[idx] == op->dev.of_node)
break;
if (idx >= MPC52xx_PSC_MAXNUM)
return -EINVAL;
pr_debug("Found %pOF assigned to ttyPSC%x\n",
mpc52xx_uart_nodes[idx], idx);
/* set the uart clock to the input clock of the psc, the different
* prescalers are taken into account in the set_baudrate() methods
* of the respective chip */
uartclk = mpc5xxx_get_bus_frequency(op->dev.of_node);
if (uartclk == 0) {
dev_dbg(&op->dev, "Could not find uart clock frequency!\n");
return -EINVAL;
}
/* Init the port structure */
port = &mpc52xx_uart_ports[idx];
spin_lock_init(&port->lock);
port->uartclk = uartclk;
port->fifosize = 512;
port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_MPC52xx_CONSOLE);
port->iotype = UPIO_MEM;
port->flags = UPF_BOOT_AUTOCONF |
(uart_console(port) ? 0 : UPF_IOREMAP);
port->line = idx;
port->ops = &mpc52xx_uart_ops;
port->dev = &op->dev;
/* Search for IRQ and mapbase */
ret = of_address_to_resource(op->dev.of_node, 0, &res);
if (ret)
return ret;
port->mapbase = res.start;
if (!port->mapbase) {
dev_dbg(&op->dev, "Could not allocate resources for PSC\n");
return -EINVAL;
}
psc_ops->get_irq(port, op->dev.of_node);
if (port->irq == 0) {
dev_dbg(&op->dev, "Could not get irq\n");
return -EINVAL;
}
dev_dbg(&op->dev, "mpc52xx-psc uart at %p, irq=%x, freq=%i\n",
(void *)port->mapbase, port->irq, port->uartclk);
/* Add the port to the uart sub-system */
ret = uart_add_one_port(&mpc52xx_uart_driver, port);
if (ret)
return ret;
platform_set_drvdata(op, (void *)port);
return 0;
}
static int
mpc52xx_uart_of_remove(struct platform_device *op)
{
struct uart_port *port = platform_get_drvdata(op);
if (port)
uart_remove_one_port(&mpc52xx_uart_driver, port);
return 0;
}
#ifdef CONFIG_PM
static int
mpc52xx_uart_of_suspend(struct platform_device *op, pm_message_t state)
{
struct uart_port *port = platform_get_drvdata(op);
if (port)
uart_suspend_port(&mpc52xx_uart_driver, port);
return 0;
}
static int
mpc52xx_uart_of_resume(struct platform_device *op)
{
struct uart_port *port = platform_get_drvdata(op);
if (port)
uart_resume_port(&mpc52xx_uart_driver, port);
return 0;
}
#endif
static void
mpc52xx_uart_of_assign(struct device_node *np)
{
int i;
/* Find the first free PSC number */
for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
if (mpc52xx_uart_nodes[i] == NULL) {
of_node_get(np);
mpc52xx_uart_nodes[i] = np;
return;
}
}
}
static void
mpc52xx_uart_of_enumerate(void)
{
static int enum_done;
struct device_node *np;
const struct of_device_id *match;
int i;
if (enum_done)
return;
/* Assign index to each PSC in device tree */
for_each_matching_node(np, mpc52xx_uart_of_match) {
match = of_match_node(mpc52xx_uart_of_match, np);
psc_ops = match->data;
mpc52xx_uart_of_assign(np);
}
enum_done = 1;
for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
if (mpc52xx_uart_nodes[i])
pr_debug("%pOF assigned to ttyPSC%x\n",
mpc52xx_uart_nodes[i], i);
}
}
MODULE_DEVICE_TABLE(of, mpc52xx_uart_of_match);
static struct platform_driver mpc52xx_uart_of_driver = {
.probe = mpc52xx_uart_of_probe,
.remove = mpc52xx_uart_of_remove,
#ifdef CONFIG_PM
.suspend = mpc52xx_uart_of_suspend,
.resume = mpc52xx_uart_of_resume,
#endif
.driver = {
.name = "mpc52xx-psc-uart",
.of_match_table = mpc52xx_uart_of_match,
},
};
/* ======================================================================== */
/* Module */
/* ======================================================================== */
static int __init
mpc52xx_uart_init(void)
{
int ret;
printk(KERN_INFO "Serial: MPC52xx PSC UART driver\n");
ret = uart_register_driver(&mpc52xx_uart_driver);
if (ret) {
printk(KERN_ERR "%s: uart_register_driver failed (%i)\n",
__FILE__, ret);
return ret;
}
mpc52xx_uart_of_enumerate();
/*
* Map the PSC FIFO Controller and init if on MPC512x.
*/
if (psc_ops && psc_ops->fifoc_init) {
ret = psc_ops->fifoc_init();
if (ret)
goto err_init;
}
ret = platform_driver_register(&mpc52xx_uart_of_driver);
if (ret) {
printk(KERN_ERR "%s: platform_driver_register failed (%i)\n",
__FILE__, ret);
goto err_reg;
}
return 0;
err_reg:
if (psc_ops && psc_ops->fifoc_uninit)
psc_ops->fifoc_uninit();
err_init:
uart_unregister_driver(&mpc52xx_uart_driver);
return ret;
}
static void __exit
mpc52xx_uart_exit(void)
{
if (psc_ops->fifoc_uninit)
psc_ops->fifoc_uninit();
platform_driver_unregister(&mpc52xx_uart_of_driver);
uart_unregister_driver(&mpc52xx_uart_driver);
}
module_init(mpc52xx_uart_init);
module_exit(mpc52xx_uart_exit);
MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>");
MODULE_DESCRIPTION("Freescale MPC52xx PSC UART");
MODULE_LICENSE("GPL");
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