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-rw-r--r--c/src/lib/libbsp/or1k/generic_or1k/console/uart.c152
1 files changed, 152 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/or1k/generic_or1k/console/uart.c b/c/src/lib/libbsp/or1k/generic_or1k/console/uart.c
new file mode 100644
index 0000000000..6f8a49443d
--- /dev/null
+++ b/c/src/lib/libbsp/or1k/generic_or1k/console/uart.c
@@ -0,0 +1,152 @@
+/**
+ * @file
+ *
+ * @ingroup generic_or1k_uart
+ *
+ * @brief UART support.
+ */
+
+/*
+ * COPYRIGHT (c) 2014-2015 Hesham ALMatary <heshamelmatary@gmail.com>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.org/license/LICENSE
+ */
+
+#include <libchip/sersupp.h>
+#include <bsp/generic_or1k.h>
+#include <bsp.h>
+#include <bsp/irq.h>
+#include <bsp/uart.h>
+#include <rtems/score/isr.h>
+
+static void uart_initialize(int minor);
+static int uart_first_open(int major, int minor, void *arg);
+static int uart_last_close(int major, int minor, void *arg);
+static int uart_read_polled(int minor);
+static ssize_t uart_write(int minor, const char *buf, size_t len);
+static void uart_write_polled(int minor, char c);
+static int uart_set_attributes(int minor, const struct termios *t);
+
+#if 0
+/*
+ * These will be useful when the driver supports interrupt driven IO.
+ */
+static rtems_vector_number uart_get_irq_number(const console_tbl *ct)
+{
+ return ct->ulIntVector;
+}
+
+static uint32_t uart_get_baud(const console_tbl *ct)
+{
+ return ct->ulClock;
+}
+#endif
+
+static void uart_set_baud(int baud)
+{
+ uint16_t divisor = (OR1K_BSP_CLOCK_FREQ) / (16 * baud);
+ OR1K_REG(OR1K_BSP_UART_REG_LINE_CTRL) =
+ OR1K_BSP_UART_REG_LINE_CTRL_DLAB;
+
+ OR1K_REG(OR1K_BSP_UART_REG_DEV_LATCH_LOW) = divisor & 0xff;
+
+ OR1K_REG(OR1K_BSP_UART_REG_DEV_LATCH_HIGH) =
+ (divisor >> 8);
+}
+
+static void uart_initialize(int minor)
+{
+ /* Set baud rate */
+ uart_set_baud(OR1K_UART_DEFAULT_BAUD);
+
+ /* Set data pattern configuration */
+ OR1K_REG(OR1K_BSP_UART_REG_LINE_CTRL) =
+ OR1K_BSP_UART_REG_LINE_CTRL_WLEN8;
+
+ /* Reset receiver and transmitter */
+ OR1K_REG(OR1K_BSP_UART_REG_FIFO_CTRL) =
+ OR1K_BSP_UART_REG_FIFO_CTRL_ENABLE_FIFO |
+ OR1K_BSP_UART_REG_FIFO_CTRL_CLEAR_RCVR |
+ OR1K_BSP_UART_REG_FIFO_CTRL_TRIGGER_14;
+
+ /* Disable all interrupts */
+ OR1K_REG(OR1K_BSP_UART_REG_INT_ENABLE) = 0x00;
+
+}
+
+static int uart_first_open(int major, int minor, void *arg)
+{
+ rtems_libio_open_close_args_t *oc = (rtems_libio_open_close_args_t *) arg;
+ struct rtems_termios_tty *tty = (struct rtems_termios_tty *) oc->iop->data1;
+ const console_tbl *ct = Console_Port_Tbl [minor];
+ console_data *cd = &Console_Port_Data [minor];
+
+ cd->termios_data = tty;
+ rtems_termios_set_initial_baud(tty, ct->ulClock);
+
+ return 0;
+}
+
+static int uart_last_close(int major, int minor, void *arg)
+{
+ return 0;
+}
+
+static int uart_read_polled(int minor)
+{
+ unsigned char lsr;
+
+ /* Get a character when avaiable */
+ do {
+ lsr = OR1K_REG(OR1K_BSP_UART_REG_LINE_STATUS);
+ } while ((lsr & OR1K_BSP_UART_REG_LINE_STATUS_DR)
+ != OR1K_BSP_UART_REG_LINE_STATUS_DR);
+
+ return OR1K_REG(OR1K_BSP_UART_REG_RX);
+}
+
+static void uart_write_polled(int minor, char c)
+{
+ unsigned char lsr;
+
+ /* Wait until there is no pending data in the transmitter FIFO (empty) */
+ do {
+ lsr = OR1K_REG(OR1K_BSP_UART_REG_LINE_STATUS);
+ } while (!(lsr & OR1K_BSP_UART_REG_LINE_STATUS_THRE));
+
+ OR1K_REG(OR1K_BSP_UART_REG_TX) = c;
+}
+
+static ssize_t uart_write(
+ int minor,
+ const char *s,
+ size_t n
+)
+{
+ ssize_t i = 0;
+
+ for (i = 0; i < n; ++i){
+ uart_write_polled(minor, s [i]);
+ }
+
+ return n;
+}
+
+static int uart_set_attributes(int minor, const struct termios *term)
+{
+ return -1;
+}
+
+const console_fns generic_or1k_uart_fns = {
+ .deviceProbe = libchip_serial_default_probe,
+ .deviceFirstOpen = uart_first_open,
+ .deviceLastClose = uart_last_close,
+ .deviceRead = uart_read_polled,
+ .deviceWrite = uart_write,
+ .deviceInitialize = uart_initialize,
+ .deviceWritePolled = uart_write_polled,
+ .deviceSetAttributes = uart_set_attributes,
+ .deviceOutputUsesInterrupts = false
+};