--- /dev/null
+/*
+ * (C) Copyright 2000
+ * Rob Taylor, Flying Pig Systems. robt@flyingpig.com.
+ *
+ * (C) Copyright 2004
+ * ARM Ltd.
+ * Philippe Robin, <philippe.robin@arm.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/* Simple U-Boot driver for the PrimeCell PL010/PL011 UARTs */
+
+#include <common.h>
+#include <watchdog.h>
+#include <asm/io.h>
+#include <serial.h>
+#include <linux/compiler.h>
+#include "serial_pl01x.h"
+
+/*
+ * Integrator AP has two UARTs, we use the first one, at 38400-8-N-1
+ * Integrator CP has two UARTs, use the first one, at 38400-8-N-1
+ * Versatile PB has four UARTs.
+ */
+#define CONSOLE_PORT CONFIG_CONS_INDEX
+static volatile unsigned char *const port[] = CONFIG_PL01x_PORTS;
+#define NUM_PORTS (sizeof(port)/sizeof(port[0]))
+
+static void pl01x_putc (int portnum, char c);
+static int pl01x_getc (int portnum);
+static int pl01x_tstc (int portnum);
+unsigned int baudrate = CONFIG_BAUDRATE;
+DECLARE_GLOBAL_DATA_PTR;
+
+static struct pl01x_regs *pl01x_get_regs(int portnum)
+{
+ return (struct pl01x_regs *) port[portnum];
+}
+
+#ifdef CONFIG_PL010_SERIAL
+
+static int pl01x_serial_init(void)
+{
+ struct pl01x_regs *regs = pl01x_get_regs(CONSOLE_PORT);
+ unsigned int divisor;
+
+ /* First, disable everything */
+ writel(0, ®s->pl010_cr);
+
+ /* Set baud rate */
+ switch (baudrate) {
+ case 9600:
+ divisor = UART_PL010_BAUD_9600;
+ break;
+
+ case 19200:
+ divisor = UART_PL010_BAUD_9600;
+ break;
+
+ case 38400:
+ divisor = UART_PL010_BAUD_38400;
+ break;
+
+ case 57600:
+ divisor = UART_PL010_BAUD_57600;
+ break;
+
+ case 115200:
+ divisor = UART_PL010_BAUD_115200;
+ break;
+
+ default:
+ divisor = UART_PL010_BAUD_38400;
+ }
+
+ writel((divisor & 0xf00) >> 8, ®s->pl010_lcrm);
+ writel(divisor & 0xff, ®s->pl010_lcrl);
+
+ /* Set the UART to be 8 bits, 1 stop bit, no parity, fifo enabled */
+ writel(UART_PL010_LCRH_WLEN_8 | UART_PL010_LCRH_FEN, ®s->pl010_lcrh);
+
+ /* Finally, enable the UART */
+ writel(UART_PL010_CR_UARTEN, ®s->pl010_cr);
+
+ return 0;
+}
+
+#endif /* CONFIG_PL010_SERIAL */
+
+#ifdef CONFIG_PL011_SERIAL
+
+static int pl01x_serial_init(void)
+{
+ struct pl01x_regs *regs = pl01x_get_regs(CONSOLE_PORT);
+ unsigned int temp;
+ unsigned int divider;
+ unsigned int remainder;
+ unsigned int fraction;
+ unsigned int lcr;
+
+#ifdef CONFIG_PL011_SERIAL_FLUSH_ON_INIT
+ /* Empty RX fifo if necessary */
+ if (readl(®s->pl011_cr) & UART_PL011_CR_UARTEN) {
+ while (!(readl(®s->fr) & UART_PL01x_FR_RXFE))
+ readl(®s->dr);
+ }
+#endif
+
+ /* First, disable everything */
+ writel(0, ®s->pl011_cr);
+
+ /*
+ * Set baud rate
+ *
+ * IBRD = UART_CLK / (16 * BAUD_RATE)
+ * FBRD = RND((64 * MOD(UART_CLK,(16 * BAUD_RATE))) / (16 * BAUD_RATE))
+ */
+ temp = 16 * baudrate;
+ divider = CONFIG_PL011_CLOCK / temp;
+ remainder = CONFIG_PL011_CLOCK % temp;
+ temp = (8 * remainder) / baudrate;
+ fraction = (temp >> 1) + (temp & 1);
+
+ writel(divider, ®s->pl011_ibrd);
+ writel(fraction, ®s->pl011_fbrd);
+
+ /* Set the UART to be 8 bits, 1 stop bit, no parity, fifo enabled */
+ lcr = UART_PL011_LCRH_WLEN_8 | UART_PL011_LCRH_FEN;
+ writel(lcr, ®s->pl011_lcrh);
+
+#ifdef CONFIG_PL011_SERIAL_RLCR
+ {
+ int i;
+
+ /*
+ * Program receive line control register after waiting
+ * 10 bus cycles. Delay be writing to readonly register
+ * 10 times
+ */
+ for (i = 0; i < 10; i++)
+ writel(lcr, ®s->fr);
+
+ writel(lcr, ®s->pl011_rlcr);
+ /* lcrh needs to be set again for change to be effective */
+ writel(lcr, ®s->pl011_lcrh);
+ }
+#endif
+ /* Finally, enable the UART */
+ writel(UART_PL011_CR_UARTEN | UART_PL011_CR_TXE | UART_PL011_CR_RXE |
+ UART_PL011_CR_RTS, ®s->pl011_cr);
+
+ return 0;
+}
+
+#endif /* CONFIG_PL011_SERIAL */
+
+static void pl01x_serial_putc(const char c)
+{
+ if (c == '\n')
+ pl01x_putc (CONSOLE_PORT, '\r');
+
+ pl01x_putc (CONSOLE_PORT, c);
+}
+
+static int pl01x_serial_getc(void)
+{
+ return pl01x_getc (CONSOLE_PORT);
+}
+
+static int pl01x_serial_tstc(void)
+{
+ return pl01x_tstc (CONSOLE_PORT);
+}
+
+static void pl01x_serial_setbrg(void)
+{
+ struct pl01x_regs *regs = pl01x_get_regs(CONSOLE_PORT);
+
+ baudrate = gd->baudrate;
+ /*
+ * Flush FIFO and wait for non-busy before changing baudrate to avoid
+ * crap in console
+ */
+ while (!(readl(®s->fr) & UART_PL01x_FR_TXFE))
+ WATCHDOG_RESET();
+ while (readl(®s->fr) & UART_PL01x_FR_BUSY)
+ WATCHDOG_RESET();
+ serial_init();
+}
+
+static void pl01x_putc (int portnum, char c)
+{
+ struct pl01x_regs *regs = pl01x_get_regs(portnum);
+
+ /* Wait until there is space in the FIFO */
+ while (readl(®s->fr) & UART_PL01x_FR_TXFF)
+ WATCHDOG_RESET();
+
+ /* Send the character */
+ writel(c, ®s->dr);
+}
+
+static int pl01x_getc (int portnum)
+{
+ struct pl01x_regs *regs = pl01x_get_regs(portnum);
+ unsigned int data;
+
+ /* Wait until there is data in the FIFO */
+ while (readl(®s->fr) & UART_PL01x_FR_RXFE)
+ WATCHDOG_RESET();
+
+ data = readl(®s->dr);
+
+ /* Check for an error flag */
+ if (data & 0xFFFFFF00) {
+ /* Clear the error */
+ writel(0xFFFFFFFF, ®s->ecr);
+ return -1;
+ }
+
+ return (int) data;
+}
+
+static int pl01x_tstc (int portnum)
+{
+ struct pl01x_regs *regs = pl01x_get_regs(portnum);
+
+ WATCHDOG_RESET();
+ return !(readl(®s->fr) & UART_PL01x_FR_RXFE);
+}
+
+static struct serial_device pl01x_serial_drv = {
+ .name = "pl01x_serial",
+ .start = pl01x_serial_init,
+ .stop = NULL,
+ .setbrg = pl01x_serial_setbrg,
+ .putc = pl01x_serial_putc,
+ .puts = default_serial_puts,
+ .getc = pl01x_serial_getc,
+ .tstc = pl01x_serial_tstc,
+};
+
+void pl01x_serial_initialize(void)
+{
+ serial_register(&pl01x_serial_drv);
+}
+
+__weak struct serial_device *default_serial_console(void)
+{
+ return &pl01x_serial_drv;
+}
Code Review / kvmfornfv.git / blobdiff