minit: Move pmp setup code to a separate function to avoid duplicating code

Currently it's being used by both enter_supervisor_mode and enter_machine_mode

1 files changed, 7 insertions, 11 deletions

diff --git a/machine/minit.c b/machine/minit.c
index de75192..953e1ba 100644
--- a/machine/minit.c
+++ b/machine/minit.c
@@ -186,7 +186,7 @@ void init_other_hart(uintptr_t hartid, uintptr_t dtb)
   boot_other_hart(dtb);
 }
 
-void enter_supervisor_mode(void (*fn)(uintptr_t), uintptr_t arg0, uintptr_t arg1)
+static inline void setup_pmp(void)
 {
   // Set up a PMP to permit access to all of memory.
   // Ignore the illegal-instruction trap if PMPs aren't supported.
@@ -198,6 +198,11 @@ void enter_supervisor_mode(void (*fn)(uintptr_t), uintptr_t arg0, uintptr_t arg1
                 ".align 2\n\t"
                 "1: csrw mtvec, t0"
                 : : "r" (pmpc), "r" (-1UL) : "t0");
+}
+
+void enter_supervisor_mode(void (*fn)(uintptr_t), uintptr_t arg0, uintptr_t arg1)
+{
+  setup_pmp();
 
   uintptr_t mstatus = read_csr(mstatus);
   mstatus = INSERT_FIELD(mstatus, MSTATUS_MPP, PRV_S);
@@ -218,16 +223,7 @@ void enter_supervisor_mode(void (*fn)(uintptr_t), uintptr_t arg0, uintptr_t arg1
 
 void enter_machine_mode(void (*fn)(uintptr_t, uintptr_t), uintptr_t arg0, uintptr_t arg1)
 {
-  // Set up a PMP to permit access to all of memory.
-  // Ignore the illegal-instruction trap if PMPs aren't supported.
-  uintptr_t pmpc = PMP_NAPOT | PMP_R | PMP_W | PMP_X;
-  asm volatile ("la t0, 1f\n\t"
-                "csrrw t0, mtvec, t0\n\t"
-                "csrw pmpaddr0, %1\n\t"
-                "csrw pmpcfg0, %0\n\t"
-                ".align 2\n\t"
-                "1: csrw mtvec, t0"
-                : : "r" (pmpc), "r" (-1UL) : "t0");
+  setup_pmp();
 
   uintptr_t mstatus = read_csr(mstatus);
   mstatus = INSERT_FIELD(mstatus, MSTATUS_MPIE, 0);