common.lds: define vbr alignment

This also creates an example of a VBR+0x100 function in interrupt.cpp

common.lds

@@ -41,6 +41,15 @@ SECTIONS
     *(COMMON)
   } > p1ram
 
+  .text.vbr ALIGN(4) : SUBALIGN(4)
+  {
+    KEEP(*(.vbr.100))
+    . = ALIGN(0x300);
+    KEEP(*(.vbr.400))
+    . = ALIGN(0x200);
+    KEEP(*(.vbr.600))
+  } > p1ram
+
   INCLUDE "debug.lds"
 }
 

example/example.mk

@@ -329,6 +329,7 @@ example/serial_transfer.elf: $(START_OBJ) $(SERIAL_TRANSFER_OBJ)
 
 INTERRUPT_OBJ = \
 	example/interrupt.o \
+	example/illslot.o \
 	sh7091/serial.o
 
 example/interrupt.elf: LDSCRIPT = $(LIB)/alt.lds

example/font_bitmap.cpp

@@ -110,10 +110,11 @@ uint32_t transform(uint32_t * ta_parameter_buf, const char * s, const uint32_t l
 					| tsp_instruction_word::texture_u_size::from_int(8)
 					| tsp_instruction_word::texture_v_size::from_int(8);
 
+    const uint32_t character_offset = ((8 * 8) / 2) * (s[string_ix] - ' ');
     const uint32_t texture_address = (offsetof (struct texture_memory_alloc, texture));
     const uint32_t texture_control_word = texture_control_word::pixel_format::_4bpp_palette
 					| texture_control_word::scan_order::twiddled
-					| texture_control_word::texture_address((texture_address + 8 * 8 * (s[string_ix] - ' ')) / 8);
+                                        | texture_control_word::texture_address((texture_address + character_offset) / 8);
 
     parameter.append<ta_global_parameter::polygon_type_0>() =
       ta_global_parameter::polygon_type_0(parameter_control_word,
@@ -131,9 +132,9 @@ uint32_t transform(uint32_t * ta_parameter_buf, const char * s, const uint32_t l
       float y = strip_vertices[i].y;
       float z = strip_vertices[i].z;
 
-      x *= 32.f;
-      y *= 32.f;
-      x += 64.f + 32 * string_ix;
+      x *= 8.f;
+      y *= 8.f;
+      x += 64.f + 8 * string_ix;
       y += 240.f;
       z = 1.f / (z + 10.f);
 
@@ -189,7 +190,7 @@ inline void inflate_character(const uint8_t * src, const uint8_t c)
   auto mem = reinterpret_cast<volatile texture_memory_alloc *>(texture_memory64);
   auto texture = reinterpret_cast<volatile uint32_t *>(mem->texture);
 
-  uint32_t offset = 8 * 8 * character_index;
+  uint32_t offset = ((8 * 8) / 2) * character_index;
 
   /*
   union {

example/illslot.s

@@ -0,0 +1,6 @@
+	.global _illslot
+_illslot:
+	rts
+	mova	test,r0
+
+test:	.long 0x12345678

example/interrupt.cpp

@@ -4,14 +4,103 @@
 
 #include "sh7091/sh7091.hpp"
 #include "sh7091/sh7091_bits.hpp"
+#include "sh7091/vbr.hpp"
+#include "systembus.hpp"
 
+void vbr100()
+{
+  serial::string("vbr100\n");
+  serial::string("expevt ");
+  serial::integer(sh7091.CCN.EXPEVT);
+  serial::string("intevt ");
+  serial::integer(sh7091.CCN.INTEVT);
+  uint32_t spc;
+  uint32_t ssr;
+  asm volatile ("stc spc,%0"
+		: "=r" (spc)
+		);
+  asm volatile ("stc ssr,%0"
+		: "=r" (ssr)
+		);
+
+  serial::string("spc ");
+  serial::integer(spc);
+  serial::string("ssr ");
+  serial::integer(ssr);
+  while (1);
+}
+
+void vbr400()
+{
+  serial::string("vbr400");
+  while (1);
+}
+
+void vbr600()
+{
+  serial::string("vbr600");
+  while (1);
+}
+
+extern "C" uint32_t * illslot(void);
 void main()
 {
-  uint32_t vbr;
+  uint32_t vbr = reinterpret_cast<uint32_t>(&__vbr_link_start) - 0x100;
 
-  asm ("stc vbr,%0" : "=r" (vbr));
+  system.IML2NRM = 0;
+  system.IML2ERR = 0;
+  system.IML2EXT = 0;
+
+  system.IML4NRM = 0;
+  system.IML4ERR = 0;
+  system.IML4EXT = 0;
+
+  system.IML6NRM = 0;
+  system.IML6ERR = 0;
+  system.IML6EXT = 0;
+
+  sh7091.CCN.INTEVT = 0;
+  sh7091.CCN.EXPEVT = 0;
+
+  uint32_t zero = 0;
+  asm volatile ("ldc %0,spc"
+		:
+		: "r" (zero));
+
+  asm volatile ("ldc %0,ssr"
+		:
+		: "r" (zero));
+
+  asm volatile ("ldc %0,vbr"
+		:
+		: "r" (vbr));
+
+
+  uint32_t sr;
+  asm volatile ("stc sr,%0"
+		: "=r" (sr));
+
+  serial::string("sr ");
+  serial::integer<uint32_t>(sr);
+
+  sr = sr & (~(1 << 28)); // BL
+
+  asm volatile ("ldc %0, sr"
+		:
+		: "r" (sr));
+
+  /*
+  uint32_t vbr2;
+  asm volatile ("stc vbr,%0"
+		: "=r" (vbr2));
+  */
 
   serial::integer<uint32_t>(vbr);
+  //serial::integer<uint32_t>(vbr2);
+  serial::integer<uint32_t>(reinterpret_cast<uint32_t>(&vbr100));
+
+  uint32_t * test = illslot();
+  serial::integer<uint32_t>(*test);
 
   while (1);
 }

runtime.cpp

@@ -46,6 +46,8 @@ void copy(uint32_t * start, const uint32_t * end, uint32_t * load)
 extern "C"
 void runtime_init()
 {
+  cache::init();
+
   // relocate text (if necessary)
   copy(&__text_link_start, &__text_link_end, &__text_load_start);
 
@@ -71,6 +73,4 @@ void runtime_init()
   while (start < end) {
     ((init_t*)(*start++))();
   }
-
-  cache::init();
 }

sh7091/vbr.hpp

@@ -0,0 +1,17 @@
+#pragma once
+
+#include <cstdint>
+
+__attribute__((section(".vbr.100")))
+__attribute__((interrupt_handler))
+void vbr100();
+
+__attribute__((section(".vbr.400")))
+__attribute__((interrupt_handler))
+void vbr400();
+
+__attribute__((section(".vbr.600")))
+__attribute__((interrupt_handler))
+void vbr600();
+
+extern uint32_t __vbr_link_start __asm("__vbr_link_start");

start.s

@@ -2,7 +2,7 @@
         .global _start
 _start:
         /* set stack pointer */
-        mov.l p1ram_end_ptr,r15
+        mov.l stack_end_ptr,r15
 
         /* mask all interrupts */
         mov.l   imask_all,r0
@@ -27,8 +27,8 @@ _start:
 	nop
 
         .align 4
-p1ram_end_ptr:
-        .long __p1ram_end
+stack_end_ptr:
+        .long __stack_end
 imask_all:
         .long 0xf0
 runtime_init_ptr:

symbols.lds

@@ -1,6 +1,5 @@
-__p1ram_start = ORIGIN(p1ram);
 /* reserve bytes for serial program loader */
-__p1ram_end = ORIGIN(p1ram) + LENGTH(p1ram) - __stack_reservation;
+__stack_end = ORIGIN(p1ram) + LENGTH(p1ram) - __stack_reservation;
 
 __text_link_start = ADDR(.text);
 __text_link_end = ADDR(.text) + SIZEOF(.text);
@@ -19,3 +18,7 @@ __ctors_link_end = ADDR(.ctors) + SIZEOF(.ctors);
 
 __bss_link_start = ADDR(.bss);
 __bss_link_end = ADDR(.bss) + SIZEOF(.bss);
+
+__vbr_link_start = ADDR(.text.vbr);
+__vbr_link_end = ADDR(.text.vbr) + SIZEOF(.text.vbr);
+__vbr_load_end = LOADADDR(.text.vbr);