Added functionality to the OpenTitanUart driver.
diff --git a/sdk/include/platform/sunburst/platform-uart.hh b/sdk/include/platform/sunburst/platform-uart.hh
index 663957e..a9acf85 100644
--- a/sdk/include/platform/sunburst/platform-uart.hh
+++ b/sdk/include/platform/sunburst/platform-uart.hh
@@ -70,6 +70,39 @@
*/
uint32_t timeoutControl;
+ /// OpenTitan UART Interrupts
+ typedef enum [[clang::flag_enum]]
+ : uint32_t{
+ /// Raised if the transmit FIFO is empty.
+ InterruptTransmitEmpty = 1 << 8,
+ /// Raised if the receiver has detected a parity error.
+ InterruptReceiveParityErr = 1 << 7,
+ /// Raised if the receive FIFO has characters remaining in the FIFO
+ /// without being
+ /// retreived for the programmed time period.
+ InterruptReceiveTimeout = 1 << 6,
+ /// Raised if break condition has been detected on receive.
+ InterruptReceiveBreakErr = 1 << 5,
+ /// Raised if a framing error has been detected on receive.
+ InterruptReceiveFrameErr = 1 << 4,
+ /// Raised if the receive FIFO has overflowed.
+ InterruptReceiveOverflow = 1 << 3,
+ /// Raised if the transmit FIFO has emptied and no transmit is ongoing.
+ InterruptTransmitDone = 1 << 2,
+ /// Raised if the receive FIFO is past the high-water mark.
+ InterruptReceiveWatermark = 1 << 1,
+ /// Raised if the transmit FIFO is past the high-water mark.
+ InterruptTransmitWatermark = 1 << 0,
+ } OpenTitanUartInterrupt;
+
+ /// FIFO Control Register Fields
+ enum [[clang::flag_enum]] : uint32_t{
+ /// Reset the transmit FIFO.
+ FifoControlTransmitReset = 1 << 1,
+ /// Reset the receive FIFO.
+ FifoControlReceiveReset = 1 << 0,
+ };
+
/// Control Register Fields
enum : uint32_t
{
@@ -95,6 +128,97 @@
ControlTransmitEnable = 1 << 0,
};
+ /// The encoding for different transmit watermark levels.
+ enum class TransmitWatermark
+ {
+ Level1 = 0x0,
+ Level2 = 0x1,
+ Level4 = 0x2,
+ Level8 = 0x3,
+ Level16 = 0x4,
+ };
+
+ /// The encoding for different receive watermark levels.
+ enum class ReceiveWatermark
+ {
+ Level1 = 0x0,
+ Level2 = 0x1,
+ Level4 = 0x2,
+ Level8 = 0x3,
+ Level16 = 0x4,
+ Level32 = 0x5,
+ Level64 = 0x6,
+ };
+
+ /**
+ * Configure parity.
+ *
+ * When `enableParity` is set, parity will be enabled.
+ * When `oddParity` is set, the odd parity will be used.
+ */
+ void parity(bool enableParity = true, bool oddParity = false) volatile
+ {
+ control = (control & ~(ControlParityEnable | ControlParityOdd)) |
+ (enableParity ? ControlParityEnable : 0) |
+ (oddParity ? ControlParityOdd : 0);
+ }
+
+ /**
+ * Configure loopback.
+ *
+ * When `systemLoopback` is set, outgoing transmitted bits are routed back
+ * the receiving line. When `lineLoopback` is set, incoming received bits
+ * are forwarded to the transmit line.
+ */
+ void loopback(bool systemLoopback = true,
+ bool lineLoopback = false) volatile
+ {
+ control = (control & ~(ControlSystemLoopback | ControlLineLoopback)) |
+ (systemLoopback ? ControlSystemLoopback : 0) |
+ (lineLoopback ? ControlLineLoopback : 0);
+ }
+
+ /// Clears the contents of the receive and transmit FIFOs.
+ void fifos_clear() volatile
+ {
+ fifoCtrl = (fifoCtrl & ~0b11) | FifoControlTransmitReset |
+ FifoControlReceiveReset;
+ }
+
+ /**
+ * Sets the level transmit watermark.
+ *
+ * When the number of bytes in the transmit FIFO reach this level,
+ * the transmit watermark interrupt will fire.
+ */
+ void transmit_watermark(TransmitWatermark level) volatile
+ {
+ fifoCtrl = static_cast<uint32_t>(level) << 5 | (fifoCtrl & 0x1f);
+ }
+
+ /**
+ * Sets the level receive watermark.
+ *
+ * When the number of bytes in the receive FIFO reach this level,
+ * the receive watermark interrupt will fire.
+ */
+ void receive_watermark(ReceiveWatermark level) volatile
+ {
+ fifoCtrl = static_cast<uint32_t>(level) << 5 | (fifoCtrl & 0b11100011);
+ }
+
+ /// Enable the given interrupt.
+ void interrupt_enable(OpenTitanUartInterrupt interrupt) volatile
+ {
+ interruptEnable = interruptEnable | interrupt;
+ }
+
+ /// Disable the given interrupt.
+ void interrupt_disable(OpenTitanUartInterrupt interrupt) volatile
+ {
+ interruptEnable = interruptEnable & ~interrupt;
+ }
+
void init(unsigned baudRate = 115'200) volatile
{
// Nco = 2^20 * baud rate / cpu frequency
