First upload. Untested software

2026-04-08 17:02:29 +02:00
commit 9b83763318
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+# startup.s - Baremetal startup code for Milk-V Duo
+
+#/* Baremetal Risc-V USB <=> Amiga Joystick/Mouse HID converter. 
+ #* March 2026 - Anders Holck
+ #* This software has no license. If you choose to use, please include my name :)
+#*/
+
+.section .text.startup
+.global _start
+
+_start:
+    # 1. Disable interrupts
+    csrw mie, zero
+
+    # 2. Set up stack pointer (end of SRAM)
+    li sp, 0x0E000000 + 128*1024
+
+    # 3. Clear BSS
+    la t0, _bss_start
+    la t1, _bss_end
+
+bss_clear_loop:
+    bgeu t0, t1, bss_clear_done
+    sd zero, 0(t0)
+    addi t0, t0, 8
+    j bss_clear_loop
+
+bss_clear_done:
+    j main
+
+.section .text
+# The main function will be in amiga_joystick_mouse.s