new directory sructure for fe310 fw

1 files changed, 34 insertions, 0 deletions

diff --git a/code/fe310/bsp/metal/metal.c b/code/fe310/bsp/metal/metal.c
new file mode 100644
index 0000000..00849b9
--- /dev/null
+++ b/code/fe310/bsp/metal/metal.c
@@ -0,0 +1,34 @@
+#include <sys/cdefs.h>
+
+#include "encoding.h"
+#include "platform.h"
+#include "prci_driver.h"
+
+extern void eos_trap_entry();
+
+static void uart_init(size_t baud_rate) {
+    GPIO_REG(GPIO_IOF_SEL) &= ~IOF0_UART0_MASK;
+    GPIO_REG(GPIO_IOF_EN) |= IOF0_UART0_MASK;
+    UART0_REG(UART_REG_DIV) = PRCI_get_cpu_freq() / baud_rate - 1;
+    UART0_REG(UART_REG_TXCTRL) |= UART_TXEN;
+    UART0_REG(UART_REG_RXCTRL) |= UART_RXEN;
+}
+
+__attribute__((constructor))
+void metal_init(void) {
+    SPI0_REG(SPI_REG_SCKDIV) = 8;
+
+    PRCI_use_default_clocks();
+    PRCI_use_pll(PLL_REFSEL_HFXOSC, 0, 1, 31, 1, -1, -1, -1);
+    uart_init(115200);
+
+    write_csr(mtvec, &eos_trap_entry);
+    if (read_csr(misa) & (1 << ('F' - 'A'))) { // if F extension is present
+        write_csr(mstatus, MSTATUS_FS); // allow FPU instructions without trapping
+        write_csr(fcsr, 0); // initialize rounding mode, undefined at reset
+    }
+}
+
+__attribute__((section(".init")))
+void __metal_synchronize_harts() {
+}