1 files changed, 44 insertions, 9 deletions
diff --git a/debug/programs/entry.S b/debug/programs/entry.S
index ff8ae30..a2ea955 100755
--- a/debug/programs/entry.S
+++ b/debug/programs/entry.S
@@ -1,9 +1,8 @@
-#ifndef ENTRY_S
-#define ENTRY_S
-
 #include "encoding.h"
 
-#define STACK_SIZE 512
+// Enough stack to store every register in case a trap handler is executed,
+// plus 33 more values.
+#define STACK_SIZE (64 * XLEN / 8)
 
 #if XLEN == 64
 # define LREG ld
@@ -61,8 +60,15 @@ handle_reset:
   la gp, __global_pointer$
 .option pop
 
-  # initialize stack pointer
-  la sp, stack_top
+  # Initialize stack pointer.
+  # Give each hart STACK_SIZE of stack.
+  # Assume hart IDs are contiguous and start at 0.
+  csrr  t0, CSR_MHARTID
+  addi  t0, t0, 1
+  li    t1, STACK_SIZE
+  mul   t0, t0, t1
+  la    sp, stack_bottom
+  add   sp, sp, t0
 
   # Clear all hardware triggers
   li    t0, ~0
@@ -73,8 +79,33 @@ handle_reset:
   csrr  t1, CSR_TSELECT
   beq   t0, t1, 1b
 
+#ifdef MULTICORE
+  csrr  t0, CSR_MHARTID
+  bnez  t0, wait_until_initialized
+#endif
+
+  la    t0, __bss_start
+  la    t1, __bss_end
+1:
+  bge   t0, t1, 2f
+  sb    zero, 0(t0)
+  addi  t0, t0, 1
+  j     1b
+2:
+#ifdef MULTICORE
+  la    t0, initialized
+  li    t1, 1
+  sw    t1, 0(t0)
+
+wait_until_initialized:      # Wait for hart 0 to perform initialization.
+  la    t0, initialized
+1:
+  lw    t1, 0(t0)
+  beqz  t1, 1b
+#endif
+
   # perform the rest of initialization in C
-  j _init
+  j     _init
 
 
 trap_entry:
@@ -157,9 +188,13 @@ trap_entry:
   addi sp, sp, 32*REGBYTES
   mret
 
+loop_forever:
+  j loop_forever
+
   // Fill the stack with data so we can see if it was overrun.
   .align 4
 stack_bottom:
-  .fill STACK_SIZE/4, 4, 0x22446688
+  .fill NHARTS * STACK_SIZE/4, 4, 0x22446688
 stack_top:
-#endif
+initialized:
+  .word 0