runtime: load support code into kernel CPU

soc/runtime/Makefile

@@ -3,7 +3,7 @@ include $(MSCDIR)/software/common.mak
 BOARD=papilio_pro
 SERIAL=/dev/ttyUSB1
 
-OBJECTS=isr.o elf_loader.o exception_jmp.o exceptions.o services.o comm_serial.o gpio.o rtio.o dds.o test_mode.o main.o
+OBJECTS=isr.o elf_loader.o kernelcpu.o exception_jmp.o exceptions.o services.o comm_serial.o gpio.o rtio.o dds.o ksupport_data.o test_mode.o main.o
 
 all: runtime.bin
 
@@ -12,7 +12,7 @@ all: runtime.bin
 
 %.bin: %.elf
 	$(OBJCOPY) -O binary $< $@
-	chmod -x $@
+	@chmod -x $@
 
 %.fbi: %.bin
 	$(MSCDIR)/mkmscimg.py -f -o $@ $<
@@ -28,7 +28,18 @@ runtime.elf: $(OBJECTS) libs
 		-L$(MSCDIR)/software/libbase \
 		-L$(MSCDIR)/software/libcompiler-rt \
 		-lbase -lcompiler-rt
-	chmod -x $@
+	@chmod -x $@
+
+ksupport.elf: ksupport.o
+	$(LD) $(LDFLAGS) \
+		-T ksupport.ld \
+		-N -o $@ \
+		$(MSCDIR)/software/libbase/crt0-$(CPU).o \
+		ksupport.o
+	@chmod -x $@
+
+ksupport_data.o: ksupport.bin
+	$(LD) -r -b binary -o $@ $<
 
 main.o: main.c
 	$(compile-dep)
@@ -52,5 +63,6 @@ flash: runtime.fbi
 
 clean:
 	$(RM) $(OBJECTS) $(OBJECTS:.o=.d) runtime.elf runtime.bin runtime.fbi .*~ *~
+	$(RM) ksupport.d ksupport.o ksupport.elf ksupport.bin
 
 .PHONY: all main.o clean libs load

soc/runtime/kernelcpu.c

@@ -0,0 +1,27 @@
+#include <generated/csr.h>
+
+#ifdef CSR_KERNEL_CPU_BASE
+
+#include <stdio.h>
+#include <string.h>
+#include <system.h>
+
+#include "kernelcpu.h"
+
+extern char _binary_ksupport_bin_start;
+extern char _binary_ksupport_bin_end;
+
+void kernelcpu_start(void)
+{
+    memcpy((void *)KERNELCPU_EXEC_ADDRESS, &_binary_ksupport_bin_start,
+        &_binary_ksupport_bin_end - &_binary_ksupport_bin_start);
+    flush_l2_cache();
+    kernel_cpu_reset_write(0);
+}
+
+void kernelcpu_stop(void)
+{
+    kernel_cpu_reset_write(1);
+}
+
+#endif /* CSR_KERNEL_CPU_BASE */

soc/runtime/kernelcpu.h

@@ -0,0 +1,14 @@
+#ifndef __KERNELCPU_H
+#define __KERNELCPU_H
+
+#include <hw/common.h>
+
+#define KERNELCPU_EXEC_ADDRESS 0x40020000
+#define KERNELCPU_KMAIN_ADDRESS 0x40022000
+
+#define KERNELCPU_MAILBOX MMPTR(0xd0000000)
+
+void kernelcpu_start(void);
+void kernelcpu_stop(void);
+
+#endif /* __KERNELCPU_H */

soc/runtime/ksupport.c

@@ -0,0 +1,16 @@
+void exception_handler(unsigned long vect, unsigned long *sp);
+void exception_handler(unsigned long vect, unsigned long *sp)
+{
+    /* TODO: report hardware exception to comm CPU */
+    for(;;);
+}
+
+extern void kmain(void);
+
+int main(void);
+int main(void)
+{
+    kmain();
+    /* TODO: report end of kernel to comm CPU */
+    return 0;
+}

soc/runtime/ksupport.ld

@@ -0,0 +1,65 @@
+INCLUDE generated/output_format.ld
+ENTRY(_start)
+
+INCLUDE generated/regions.ld
+
+/* First 128K of main memory are reserved for runtime code/data
+ * then comes kernel memory. First 8K of kernel memory are for support code.
+ */
+MEMORY {
+    ksupport : ORIGIN = 0x40020000, LENGTH = 0x2000
+}
+
+/* Then comes the payload. */
+PROVIDE(kmain = ORIGIN(ksupport) + LENGTH(ksupport));
+
+/* On biprocessor systems, kernel stack is at the end of main RAM,
+ * before the runtime stack. Leave 1M for runtime stack.
+ */
+PROVIDE(_fstack = 0x40000000 + LENGTH(main_ram) - 1024*1024 - 4);
+
+SECTIONS
+{
+    .text :
+    {
+        _ftext = .;
+        *(.text .stub .text.* .gnu.linkonce.t.*)
+        _etext = .;
+    } > ksupport
+
+    .rodata :
+    {
+        . = ALIGN(4);
+        _frodata = .;
+        *(.rodata .rodata.* .gnu.linkonce.r.*)
+        *(.rodata1)
+        _erodata = .;
+    } > ksupport
+
+    .data :
+    {
+        . = ALIGN(4);
+        _fdata = .;
+        *(.data .data.* .gnu.linkonce.d.*)
+        *(.data1)
+        _gp = ALIGN(16);
+        *(.sdata .sdata.* .gnu.linkonce.s.*)
+        _edata = .;
+    } > ksupport
+
+    .bss :
+    {
+        . = ALIGN(4);
+        _fbss = .;
+        *(.dynsbss)
+        *(.sbss .sbss.* .gnu.linkonce.sb.*)
+        *(.scommon)
+        *(.dynbss)
+        *(.bss .bss.* .gnu.linkonce.b.*)
+        *(COMMON)
+        . = ALIGN(4);
+        _ebss = .;
+        . = ALIGN(8);
+        _heapstart = .;
+    } > ksupport
+}

soc/runtime/main.c

@@ -10,18 +10,17 @@
 #include "test_mode.h"
 #include "comm.h"
 #include "elf_loader.h"
+#include "kernelcpu.h"
 #include "exceptions.h"
 #include "services.h"
 #include "rtio.h"
 #include "dds.h"
 
-
 static struct symbol symtab[128];
 static int _symtab_count;
 static char _symtab_strings[128*16];
 static char *_symtab_strptr;
 
-
 static void symtab_init(void)
 {
     memset(symtab, 0, sizeof(symtab));
@@ -132,7 +131,11 @@ int main(void)
     irq_setie(1);
     uart_init();
 
-    puts("ARTIQ runtime built "__DATE__" "__TIME__"\n");
+#ifdef CSR_KERNEL_CPU_BASE
+    puts("ARTIQ runtime built "__DATE__" "__TIME__" for biprocessor systems\n");
+#else
+    puts("ARTIQ runtime built "__DATE__" "__TIME__" for uniprocessor systems\n");
+#endif
     blink_led();
 
     if(check_test_mode()) {

soc/runtime/test_mode.c

@@ -305,30 +305,6 @@ static char *get_token(char **str)
     return d;
 }
 
-#ifdef CSR_KERNEL_CPU_BASE
-static const unsigned int test_program[] = {
-    0x1860dead, //     l.movhi r3,0xdead
-    0x1880d000, //     l.movhi r4,0xd000
-    0xa863beef, //     l.ori r3,r3,0xbeef
-    0xd4041800, //     l.sw 0(r4),r3
-    0x00000000, //     l.j +0
-    0x15000000, //     l.nop
-};
-
-static void cputest(void)
-{
-    int i;
-
-    kernel_cpu_reset_write(1);
-    MMPTR(0xd0000000) = 0;
-    memcpy((void *)0x41000000, test_program, sizeof(test_program));
-    flush_l2_cache();
-    kernel_cpu_reset_write(0);
-    for(i=0;i<10;i++)
-        printf("%08x\n", MMPTR(0xd0000000));
-}
-#endif
-
 static void do_command(char *c)
 {
     char *token;
@@ -351,10 +327,6 @@ static void do_command(char *c)
     else if(strcmp(token, "ddsftw") == 0) ddsftw(get_token(&c), get_token(&c));
     else if(strcmp(token, "ddstest") == 0) ddstest(get_token(&c));
 
-#ifdef CSR_KERNEL_CPU_BASE
-    else if(strcmp(token, "cputest") == 0) cputest();
-#endif
-
     else if(strcmp(token, "") != 0)
         printf("Command not found\n");
 }