serial/8250/8250_early.c

14  * we locate the device directly by its MMIO or I/O port address.
36 static unsigned int serial8250_early_in(struct uart_port *port, int offset)
38 	offset <<= port->regshift;
40 	switch (port->iotype) {
42 		return readb(port->membase + offset);
44 		return readw(port->membase + offset);
46 		return readl(port->membase + offset);
48 		return ioread32be(port->membase + offset);
50 		return inb(port->iobase + offset);
56 static void serial8250_early_out(struct uart_port *port, int offset, int value)
58 	offset <<= port->regshift;
60 	switch (port->iotype) {
62 		writeb(value, port->membase + offset);
65 		writew(value, port->membase + offset);
68 		writel(value, port->membase + offset);
71 		iowrite32be(value, port->membase + offset);
74 		outb(value, port->iobase + offset);
79 static void serial_putc(struct uart_port *port, unsigned char c)
83 	serial8250_early_out(port, UART_TX, c);
86 		status = serial8250_early_in(port, UART_LSR);
97 	struct uart_port *port = &device->port;
99 	uart_console_write(port, s, count, serial_putc);
107 	struct uart_port *port = &device->port;
112 		status = serial8250_early_in(port, UART_LSR);
115 		s[num_read++] = serial8250_early_in(port, UART_RX);
126 	struct uart_port *port = &device->port;
131 	serial8250_early_out(port, UART_LCR, UART_LCR_WLEN8);		/* 8n1 */
132 	ier = serial8250_early_in(port, UART_IER);
133 	serial8250_early_out(port, UART_IER, ier & UART_IER_UUE); /* no interrupt */
134 	serial8250_early_out(port, UART_FCR, 0);	/* no fifo */
135 	serial8250_early_out(port, UART_MCR, UART_MCR_DTR | UART_MCR_RTS);
137 	if (port->uartclk) {
138 		divisor = DIV_ROUND_CLOSEST(port->uartclk, 16 * device->baud);
139 		c = serial8250_early_in(port, UART_LCR);
140 		serial8250_early_out(port, UART_LCR, c | UART_LCR_DLAB);
141 		serial8250_early_out(port, UART_DLL, divisor & 0xff);
142 		serial8250_early_out(port, UART_DLM, (divisor >> 8) & 0xff);
143 		serial8250_early_out(port, UART_LCR, c & ~UART_LCR_DLAB);
150 	if (!(device->port.membase || device->port.iobase))
154 		struct uart_port *port = &device->port;
158 		ier = serial8250_early_in(port, UART_IER);
159 		serial8250_early_out(port, UART_IER, ier & UART_IER_UUE);
179 	struct uart_port *port = &device->port;
181 	if (!(device->port.membase || device->port.iobase))
184 	port->regshift = 2;