From ff48af07b08c0870ea950335fec338a828f88c27 Mon Sep 17 00:00:00 2001
From: David Guillen Fandos
Date: Sun, 25 Apr 2021 21:16:46 +0200
Subject: Fix RTC support for MIPS

---
 psp/mips_emit.h | 38 ++++++++++++++++++++++++++------------
 1 file changed, 26 insertions(+), 12 deletions(-)

diff --git a/psp/mips_emit.h b/psp/mips_emit.h
index 73f589a..12685e8 100644
--- a/psp/mips_emit.h
+++ b/psp/mips_emit.h
@@ -2984,24 +2984,23 @@ static void emit_ignorestore_stub(unsigned size, u8 **tr_ptr) {
   mips_emit_jr(mips_reg_ra);
   mips_emit_nop();
 
-  // Region 8-B
-  tmemst[size][ 8] = tmemst[size][ 9] = 
-  tmemst[size][10] = tmemst[size][11] = (u32)translation_ptr;
+  // Region 9-C
+  tmemst[size][ 9] = tmemst[size][10] =
+  tmemst[size][11] = tmemst[size][12] = (u32)translation_ptr;
 
-  mips_emit_srl(reg_temp, reg_a0, 26);               // Check 6 MSB to be 0x02
-  mips_emit_xori(reg_temp, reg_temp, 0x02);
+  mips_emit_srl(reg_temp, reg_a0, 24);
+  mips_emit_addiu(reg_temp, reg_temp, -9);
+  mips_emit_srl(reg_temp, reg_temp, 2);
   mips_emit_b(bne, reg_temp, reg_zero, st_phndlr_branch(size));
   mips_emit_nop();
   mips_emit_jr(mips_reg_ra);
   mips_emit_nop();
 
-  // Region C or F (or bigger!)
-  tmemst[size][12] = tmemst[size][15] = (u32)translation_ptr;
+  // Region F or higher
+  tmemst[size][15] = (u32)translation_ptr;
   mips_emit_srl(reg_temp, reg_a0, 24);
-  mips_emit_sltiu(reg_rv, reg_temp, 0x0F);
-  mips_emit_b(beq, reg_rv, reg_zero, 3);    // If 15 or bigger, ignore store
-  mips_emit_xori(reg_rv, reg_temp, 0x0C);
-  mips_emit_b(bne, reg_temp, reg_zero, st_phndlr_branch(size));
+  mips_emit_sltiu(reg_rv, reg_temp, 0x0F);  // Is < 15?
+  mips_emit_b(bne, reg_rv, reg_zero, st_phndlr_branch(size));
   mips_emit_nop();
   mips_emit_jr(mips_reg_ra);
   mips_emit_nop();
@@ -3009,7 +3008,7 @@ static void emit_ignorestore_stub(unsigned size, u8 **tr_ptr) {
   *tr_ptr = translation_ptr;
 }
 
-// Stubs for regions with EEPROM or flash/SRAM
+// Stubs for regions with EEPROM or flash/SRAM (also RTC)
 static void emit_saveaccess_stub(u8 **tr_ptr) {
   unsigned opt, i, strop;
   u8 *translation_ptr = *tr_ptr;
@@ -3062,6 +3061,21 @@ static void emit_saveaccess_stub(u8 **tr_ptr) {
     }
   }
 
+  // RTC writes, only for 16 bit accesses
+  for (strop = 0; strop <= 3; strop++) {
+    tmemst[strop][8] = (u32)translation_ptr;
+    mips_emit_srl(reg_temp, reg_a0, 24);
+    mips_emit_xori(reg_rv, reg_temp, 0x08);
+    mips_emit_b(bne, reg_rv, reg_zero, st_phndlr_branch(strop));
+    if (strop == 1) {
+      emit_mem_call(&write_rtc, 0xFF);  // Addr
+    } else {
+      mips_emit_nop();
+      mips_emit_jr(mips_reg_ra);   // Do nothing
+      mips_emit_nop();
+    }
+  }
+
   // Region 4 writes  
   // I/O writes are also a bit special, they can trigger things like DMA, IRQs...
   // Also: aligned (strop==3) accesses do not trigger IRQs
-- 
cgit v1.2.3