Add mips routine for far stubs.

Change-Id: Ia78369067aa89369dabdbaeb844cfc0a08c18714

1 files changed, 21 insertions, 5 deletions

diff --git a/lib/StubLayout.cpp b/lib/StubLayout.cpp
index 929ee5b..733e665 100644
--- a/lib/StubLayout.cpp
+++ b/lib/StubLayout.cpp
@@ -23,8 +23,10 @@
 #include <stdlib.h>
 #include <sys/mman.h>
 
-#ifdef __arm__
-#define STUB_SIZE 8 // 8 bytes (2 words)
+#if defined(__arm__)
+#define STUB_SIZE 8
+#elif defined(__mips__)
+#define STUB_SIZE 16
 #endif
 
 StubLayout::StubLayout() : table(NULL), count(0) {
@@ -36,7 +38,7 @@ void StubLayout::initStubTable(unsigned char *table_, size_t count_) {
 }
 
 void *StubLayout::allocateStub(void *addr) {
-#ifdef __arm__
+#if defined(__arm__) || defined(__mips__)
   // Check if we have created this stub or not.
   std::map<void *, void *>::iterator index_iter = stub_index.find(addr);
 
@@ -67,7 +69,7 @@ void *StubLayout::allocateStub(void *addr) {
 }
 
 void StubLayout::setStubAddress(void *stub_, void *addr) {
-#ifdef __arm__
+#if defined(__arm__)
   uint8_t *stub = (uint8_t *)stub_;
   stub[0] = 0x04; // ldr pc, [pc, #-4]
   stub[1] = 0xf0; // ldr pc, [pc, #-4]
@@ -76,11 +78,25 @@ void StubLayout::setStubAddress(void *stub_, void *addr) {
 
   void **target = (void **)(stub + 4);
   *target = addr;
+
+#elif defined(__mips__)
+  uint32_t addr32 = (uint32_t)(uintptr_t)addr;
+  uint16_t addr_hi16 = (addr32 >> 16) &  0xffff;
+  uint16_t addr_lo16 = addr32 & 0xffff;
+
+  uint32_t *stub = (uint32_t *)stub_;
+  stub[0] = 0x3c190000ul | addr_hi16; // lui
+  stub[1] = 0x37390000ul | addr_lo16; // ori
+  stub[2] = 0x03200008ul; // jr (jump register)
+  stub[3] = 0x00000000ul; // nop
+
+#else
+  rsl_assert(0 && "Stub is not supported on this platform");
 #endif
 }
 
 size_t StubLayout::calcStubTableSize(size_t count) const {
-#ifdef __arm__
+#if defined(__arm__) || defined(__mips__)
   return count * STUB_SIZE;
 #else
   return 0;