#5 Moop Video/exception overhaul

Makefile.cfg

@@ -86,7 +86,7 @@ TARGETCCVER       = 4
 
 # You generally shouldn't change this unless you are making forked
 # versions (or test versions)
-VERSION			  = 1.0.5
+VERSION			  = 1.1.1
 
 # Define this if you want a standalone, statically linked, no dependency binary
 # This is on by default for MinGW/MSYS
@@ -98,6 +98,11 @@ VERSION			  = 1.0.5
 # Set to 1 to enable, 0 to disable.
 SAVE_MY_FANS      = 0
 
+# This sets the number of seconds to show the register dump on-screen if an
+# exception occurs. Maximum is 60 seconds, minimum is 0 seconds (no display),
+# default is 15 seconds.
+EXCEPTION_SECONDS = 15
+
 #
 # IMPORTANT IP ADDRESS INFORMATION:
 #

NETWORK

@@ -11,6 +11,6 @@ dcload-ip implements (to some extent) the following protocols:
 
 * UDP  - dcload-ip uses UDP for transfering data and commands 
 
-
+* DHCP - dcload-ip can use IPv4 DHCP to get an IP address now
 
 

example-src/Makefile

@@ -2,44 +2,44 @@ include ../Makefile.cfg
 
 CC	= $(TARGETCC)
 INCLUDE	= -I../target-inc
-CFLAGS	= $(TARGETCFLAGS)
+CFLAGS	= $(TARGETCFLAGS) -Wall -Wextra -Wno-unused -ffreestanding -fno-zero-initialized-in-bss -fomit-frame-pointer -fno-strict-aliasing -fno-unwind-tables -fno-asynchronous-unwind-tables -fno-exceptions -fno-delete-null-pointer-checks -fno-stack-protector -fno-stack-check -fmerge-constants -fmerge-all-constants -std=gnu11
 OBJCOPY	= $(TARGETOBJCOPY)
 
-OBJECTS	= crt0.o dcload-syscall.o dcload-syscalls.o memcpy.o
+OBJECTS	= crt0.o startup_support.o dcload-syscall.o dcload-syscalls.o memcpy.o
 
 .c.o:
-	$(CC) $(CFLAGS) $(INCLUDE) -o $@ -c $< 
+	$(CC) $(CFLAGS) $(INCLUDE) -Wa,-adghlmns=$*.asm -o $@ -c $< 
 
 .S.o:
-	$(CC) $(CFLAGS) $(INCLUDE) -o $@ -c $< 
+	$(CC) $(CFLAGS) $(INCLUDE) -Wa,-adghlmns=$*.asm -o $@ -c $< 
 
 .s.o:
-	$(CC) $(CFLAGS) $(INCLUDE) -o $@ -c $< 
+	$(CC) $(CFLAGS) $(INCLUDE) -Wa,-adghlmns=$*.asm -o $@ -c $< 
 
 all: console-test.bin exception-test.bin gethostinfo.bin
 
 console-test.bin: console-test
-	$(OBJCOPY) -O binary $< $@	
+	$(OBJCOPY) -O binary $< $@
 
 exception-test.bin: exception-test
-	$(OBJCOPY) -O binary $< $@	
+	$(OBJCOPY) -O binary $< $@
 
 gethostinfo.bin: gethostinfo
-	$(OBJCOPY) -O binary $< $@	
+	$(OBJCOPY) -O binary $< $@
 
 console-test: $(OBJECTS) console-test.o
-	$(CC) $(CFLAGS) -Wl,-Tdc$(TARGETCCVER).x -nostartfiles -nostdlib $^ -o $@ -lgcc
+	$(CC) $(CFLAGS) -Wl,--warn-common -Wl,--no-undefined -Wl,-Map,console-test.map -Wl,-Tdc$(TARGETCCVER).x -nostartfiles -nostdlib $^ -o $@ -lgcc
 
 gethostinfo: $(OBJECTS) gethostinfo.o
-	$(CC) $(CFLAGS) -Wl,-Tdc$(TARGETCCVER).x -nostartfiles -nostdlib $^ -o $@ -lgcc
+	$(CC) $(CFLAGS) -Wl,--warn-common -Wl,--no-undefined -Wl,-Map,gethostinfo.map -Wl,-Tdc$(TARGETCCVER).x -nostartfiles -nostdlib $^ -o $@ -lgcc
 
 exception-test: $(OBJECTS) exception-test.o
-	$(CC) $(CFLAGS) -Wl,-Tdc$(TARGETCCVER).x -nostartfiles -nostdlib $^ -o $@ -lgcc
+	$(CC) $(CFLAGS) -Wl,--warn-common -Wl,--no-undefined -Wl,-Map,exception-test.map -Wl,-Tdc$(TARGETCCVER).x -nostartfiles -nostdlib $^ -o $@ -lgcc
 
 .PHONY : clean
 clean:
-	rm -f *.o console-test exception-test gethostinfo
+	rm -f *.o console-test exception-test gethostinfo  *.map *.asm
 
 .PHONY : distclean
-distclean: clean 
+distclean: clean
 	rm -f *.bin

example-src/README

@@ -1,11 +1,13 @@
 crt0.S			a version of crt0.S 
+startup_support.c a helper file for crt0.S
 dc.x			a linker script for the Dreamcast
 dcload-syscall.S	assembly to call a dcload syscall
 dcload-syscall.h	lowlevel dcload syscall header
 dcload-syscalls.c	dcload syscall c source
 dcload-syscalls.h	dcload syscall header
 
 To use this stuff in your own code, #include "dcload-syscalls.h" and link with dcload-syscalls.o and dcload-syscall.o.
+(Well, it's not quite that simple. There are a bunch of headers in target-inc that are needed, as well. The way this was put together initially was very sloppily and did not stand the test of time.)
 
 You're welcome to use any of the code in this directory in any way you please.
 I'm not responsible if it causes you to fart fire, grow a third eye, etc, etc.

example-src/console-test.c

@@ -1,6 +1,6 @@
 #include "dcload-syscalls.h"
 
-int main(void)
+void main(void)
 {
     int fd;
     unsigned char buffer[2048];

example-src/crt0.S

@@ -12,17 +12,17 @@ setup_cache:
 	mov.l	ccr_addr,r0
 	mov.w	ccr_data,r1
 	mov.l	r1,@r0
-	mov.l	start_2_k,r0	
+	mov.l	start_2_k,r0
 	nop
 	nop
 	nop
 	nop
 	nop
 	nop
 	nop
-	jmp	@r0	
+	jmp	@r0
 	nop
-start_2:		
+start_2:
 	mov.l	old_stack_k,r14
 	mov.l	r15,@r14
 	mov.l	old_pr_k,r14
@@ -33,21 +33,30 @@ start_2:
 	! zero out bss
 	mov.l	edata_k,r0
 	mov.l	end_k,r1
+	cmp/eq r0,r1 ! unless there is no bss
+	bt no_bss
 	mov	#0,r2
 start_l:
 	mov.l	r2,@r0
 	add	#4,r0
-	cmp/ge	r0,r1
+	cmp/hi r0,r1 ! This was cmp/ge before, which would always write 4 bytes beyond the end...
 	bt	start_l
 
+no_bss:
 #if defined (__SH3E__) || defined(__SH4_SINGLE__) || defined(__SH4__) || defined(__SH4_SINGLE_ONLY)
 	mov.l set_fpscr_k, r1
 	jsr @r1
 	mov #0,r4
-	lds r3,fpscr
+!	lds r3,fpscr ! This isn't necessary.
 #endif /*  defined (__SH3E__) || defined(__SH4_SINGLE__) || defined(__SH4__) || defined(__SH4_SINGLE_ONLY__) */
+	! enable exceptions and the FPU
+	stc	sr,r0
+	mov.l	sr_mask,r1
+	and	r1,r0
+	or	#0xf0,r0
+	ldc	r0,sr
 
-	! call the mainline	
+	! call the mainline
 	mov.l	main_k,r0
 	jsr	@r0
 	or	r0,r0
@@ -60,10 +69,10 @@ start_l:
 
 ___exit:
 	mov.l	old_pr_k,r14
-	mov.l	@r14,r15	
+	mov.l	@r14,r15
 	lds	r15,pr
 	mov.l	old_stack_k,r14
-	mov.l	@r14,r15	
+	mov.l	@r14,r15
 	rts
 	nop
 
@@ -72,12 +81,15 @@ _atexit:
 	nop
 
 	.align 4
+sr_mask:
+	.long	0xefff7fff
 #if defined (__SH3E__) || defined(__SH4_SINGLE__) || defined(__SH4__) || defined(__SH4_SINGLE_ONLY__)
 set_fpscr_k:
-	.long	___set_fpscr
+! __set_fpscr() is deprecated, use this wrapper for builtin instead
+	.long	___call_builtin_sh_set_fpscr
 #endif /*  defined (__SH3E__) || defined(__SH4_SINGLE__) || defined(__SH4__) || defined(SH4_SINGLE_ONLY) */
 stack_k:
-	.long	_stack	
+	.long	_stack
 edata_k:
 	.long	_edata
 end_k:
@@ -100,7 +112,7 @@ _old_pr:
 setup_cache_k:
 	.long	setup_cache
 start_2_k:	
-	.long	start_2	
+	.long	start_2
 p2_mask:
 	.long	0xa0000000
 ccr_addr:
@@ -109,7 +121,7 @@ ccr_data:
 	.word	0x090b
 
 	.align 4
-		
+
 #ifdef __ELF__
 	.section .stack,"aw"
 #else

example-src/dc3.x

@@ -88,8 +88,8 @@ SECTIONS
   .rela.bss      : { *(.rela.bss)		}
   .rel.plt       : { *(.rel.plt)		}
   .rela.plt      : { *(.rela.plt)		}
-  .init          : 
-  { 
+  .init          :
+  {
     KEEP (*(.init))
   } =0
   .plt      : { *(.plt)	}
@@ -123,7 +123,7 @@ SECTIONS
   .data1   : { *(.data1) }
   .eh_frame : { *(.eh_frame) }
   .gcc_except_table : { *(.gcc_except_table) }
-  .ctors   ALIGN(4): 
+  .ctors   ALIGN(4):
   {
     ___ctors = .;
     /* gcc uses crtbegin.o to find the start of
@@ -159,12 +159,13 @@ SECTIONS
   /* We want the small data sections together, so single-instruction offsets
      can access them all, and initialized data all before uninitialized, so
      we can shorten the on-disk segment size.  */
-  .sdata     : 
+  .sdata     :
   {
-    *(.sdata) 
+    *(.sdata)
     *(.sdata.*)
     *(.gnu.linkonce.s.*)
   }
+  . = ALIGN(32 / 8);
   _edata = .;
   PROVIDE (edata = .);
   __bss_start = .;

example-src/dc4.x

@@ -163,6 +163,7 @@ SECTIONS
   {
     *(.sdata .sdata.* .gnu.linkonce.s.*)
   }
+  . = ALIGN(32 / 8);
   _edata = .; PROVIDE (edata = .);
   __bss_start = .;
   .sbss           :
@@ -179,9 +180,16 @@ SECTIONS
    /* Align here to ensure that the .bss section occupies space up to
       _end.  Align after .bss to ensure correct alignment even if the
       .bss section disappears because there are no input sections.
-      FIXME: Why do we need it? When there is no .bss section, we don't
+      Question: Why do we need it? When there is no .bss section, we don't
       pad the .data section.  */
-   . = ALIGN(. != 0 ? 32 / 8 : 1);
+   /* Answer: bss must exist and be at least 4 bytes in size because
+			crt0.S will try to zero out bss even if there isn't one. So we
+			always need a bss section, and moreover it (_edata in particular)
+			must be aligned to 4 bytes as 'mov.l Rm,@Rn' will crash otherwise.
+			This now still needs to be aligned to 4 bytes (to line up with _end if
+			there is no bss), but with a change to crt0.S	it at least will check if
+			there is a bss section first... */
+   . = ALIGN(. != 0 ? 32 /8 : 1);
   }
   . = ALIGN(32 / 8);
   . = ALIGN(32 / 8);

example-src/dcload-syscall.h

@@ -2,6 +2,8 @@
 #define __DCLOAD_SYSCALL_H__
 
 int dcloadsyscall(unsigned int syscall, ...);
+void __exit(int status);
+void __call_builtin_sh_set_fpscr(unsigned int value);
 
 #define pcreadnr 0
 #define pcwritenr 1
@@ -11,7 +13,7 @@ int dcloadsyscall(unsigned int syscall, ...);
 #define pclinknr 5
 #define pcunlinknr 6
 #define pcchdirnr 7
-#define pcchmodnr 8        
+#define pcchmodnr 8
 #define pclseeknr 9
 #define pcfstatnr 10
 #define pctimenr 11