[pk] load pk at addr 0; user stack top = MEMSIZE

Makefile.in

@@ -232,14 +232,14 @@ $(2)_junk += $$($(2)_test_outs)
 
 # Build programs
 
-$(2)_prog_objs      := $$(patsubst %.c, %.o, $$($(2)_prog_srcs))
+$(2)_prog_objs      := $$(patsubst %.S, %.o, $$($(2)_prog_srcs))
 $(2)_prog_deps      := $$(patsubst %.o, %.d, $$($(2)_prog_objs))
-$(2)_prog_exes      := $$(patsubst %.c, %, $$($(2)_prog_srcs))
+$(2)_prog_exes      := $$(patsubst %.S, %, $$($(2)_prog_srcs))
 $(2)_prog_libs      := $(1) $$($(2)_reverse_deps)
 $(2)_prog_libnames  := $$(patsubst %, lib%.a, $$($(2)_prog_libs))
 $(2)_prog_libarg    := -L. $$(patsubst %, -l%, $$($(2)_prog_libs))
 
-$$($(2)_prog_objs) : %.o : %.c
+$$($(2)_prog_objs) : %.o : %.S
 	$(COMPILE) -c $$<
 
 $$($(2)_prog_exes) : % : %.o $$($(2)_prog_libnames)
@@ -250,11 +250,11 @@ $(2)_junk += $$($(2)_prog_objs) $$($(2)_prog_deps) $$($(2)_prog_exes)
 
 # Build programs which will be installed
 
-$(2)_install_prog_objs := $$(patsubst %.c, %.o, $$($(2)_install_prog_srcs))
+$(2)_install_prog_objs := $$(patsubst %.S, %.o, $$($(2)_install_prog_srcs))
 $(2)_install_prog_deps := $$(patsubst %.o, %.d, $$($(2)_install_prog_objs))
-$(2)_install_prog_exes := $$(patsubst %.c, %, $$($(2)_install_prog_srcs))
+$(2)_install_prog_exes := $$(patsubst %.S, %, $$($(2)_install_prog_srcs))
 
-$$($(2)_install_prog_objs) : %.o : %.c
+$$($(2)_install_prog_objs) : %.o : %.S
 	$(COMPILE) -c $$<
 
 $$($(2)_install_prog_exes) : % : %.o $$($(2)_prog_libnames)

pk/fp.c

@@ -20,7 +20,7 @@ validate_address(trapframe_t* tf, long addr, int size, int store)
 {
   if(addr & (size-1))
     store ? handle_misaligned_store(tf) : handle_misaligned_load(tf);
-  if(addr >= USER_MEM_SIZE)
+  if(addr < USER_START)
     store ? handle_fault_store(tf) : handle_fault_load(tf);
 }
 

pk/pcr.h

@@ -20,6 +20,7 @@
 #define PCR_COUNT    4
 #define PCR_COMPARE  5
 #define PCR_CAUSE    6
+#define PCR_MEMSIZE  8
 #define PCR_TOHOST   16
 #define PCR_FROMHOST 17
 #define PCR_CONSOLE  18
@@ -29,6 +30,8 @@
 #define CR_FSR       0
 #define CR_TID       29
 
+#define MEMSIZE_SHIFT 12
+
 #define TIMER_PERIOD 0x1000000
 #define TIMER_IRQ 7
 

pk/pk.c

@@ -147,23 +147,22 @@ struct args
 
 static struct args* mainvars_init()
 {
-  void* loc = (void*)USER_MEM_SIZE-USER_MAINVARS_SIZE;
+  long loc = (mfpcr(PCR_MEMSIZE) << MEMSIZE_SHIFT) - USER_MAINVARS_SIZE;
 
-  sysret_t r = frontend_syscall(SYS_getmainvars,
-    USER_MEM_SIZE-USER_MAINVARS_SIZE, USER_MAINVARS_SIZE, 0, 0);
+  sysret_t r = frontend_syscall(SYS_getmainvars, loc, USER_MAINVARS_SIZE, 0, 0);
   kassert(r.result == 0);
 
   return (struct args*)loc;
 }
 
-static void jump_usrstart(const char* fn)
+static void jump_usrstart(const char* fn, long sp)
 {
   trapframe_t tf;
 
   int user64;
   long start = load_elf(fn, &user64);
   asm volatile("cflush; fence");
-  init_tf(&tf, start, USER_MEM_SIZE-USER_MAINVARS_SIZE, user64);
+  init_tf(&tf, start, sp, user64);
   pop_tf(&tf);
 }
 
@@ -173,5 +172,5 @@ void boot()
   file_init();
 
   struct args* args = mainvars_init();
-  jump_usrstart((void*)(long)args->argv[0]);
+  jump_usrstart((char*)(long)args->argv[0], (long)args);
 }

pk/pk.h

@@ -1,7 +1,6 @@
 #ifndef _PK_H
 #define _PK_H
 
-#define USER_MEM_SIZE 0x70000000
 #define USER_MAINVARS_SIZE 0x1000
 #define USER_START 0x10000
 

pk/pk.ld

@@ -11,15 +11,14 @@ SECTIONS
 
   /* Begining of code and text segment */
   . = 0x00000000;
-  .boottext :
-  {
-    riscv-pk.o(.boottext)
-  }
-
-  . = 0x70000000;
   _ftext = .;
   PROVIDE( eprol = . );
 
+  .text :
+  {
+    riscv-pk.o(.text)
+  }
+
   /* text: Program code section */
   .text : 
   {

pk/pk.mk.in

@@ -30,4 +30,4 @@ pk_asm_srcs = \
 pk_test_srcs =
 
 pk_install_prog_srcs = \
-	riscv-pk.c \
+	riscv-pk.S \

pk/riscv-pk.S

@@ -0,0 +1,37 @@
+#include "pcr.h"
+#include "pk.h"
+
+.section .text,"ax",@progbits
+.globl __start
+.ent __start
+__start:
+
+  lui $sp, %hi(stack_top)
+  add $sp, $sp, %lo(stack_top)
+
+  lui $t0, %hi(trap_entry)
+  add $t0, $t0, %lo(trap_entry)
+  mtpcr $t0, ASM_CR(PCR_EVEC)
+
+  mtpcr $x0, ASM_CR(PCR_COUNT)
+  mtpcr $x0, ASM_CR(PCR_COMPARE)
+
+  li $t0, SR_S | SR_PS | SR_ET | SR_IM | SR_EC | SR_SX
+  or $t1, $t0, SR_EF | SR_EV
+  mtpcr $t1, ASM_CR(PCR_SR)
+  mfpcr $t1, ASM_CR(PCR_SR)
+  mtpcr $t0, ASM_CR(PCR_SR)
+  
+  and $t2, $t1, SR_EF
+  lui $t0, %hi(have_fp)
+  sw  $t2, %lo(have_fp)($t0)
+  
+  and $t2, $t1, SR_EV
+  lui $t0, %hi(have_vector)
+  sw  $t2, %lo(have_vector)($t0)
+
+  lui $t0, %hi(boot)
+  jalr.j $t0, %lo(boot)
+  #j boot
+
+.end __start

pk/riscv-pk.c

@@ -1,32 +0,0 @@
-#include "pcr.h"
-#include "pk.h"
-
-void __attribute__((section(".boottext"))) __start()
-{
-  extern char stack_top;
-  asm volatile("move $sp,%0" : : "r"(&stack_top-64) : "memory");
-
-  extern char trap_entry;
-  register void* te = &trap_entry;
-  mtpcr(te,PCR_EVEC);
-
-  mtpcr(0,PCR_COUNT);
-  mtpcr(0,PCR_COMPARE);
-
-  register long sr0 = SR_S | SR_PS | SR_ET | SR_IM | SR_EC;
-  if(sizeof(void*) == 8)
-    sr0 |= SR_SX;
-
-  mtpcr(sr0 | SR_EF, PCR_SR);
-  have_fp = mfpcr(PCR_SR) & SR_EF;
-  mtpcr(sr0, PCR_SR);
-
-  mtpcr(sr0 | SR_EV, PCR_SR);
-  have_vector = mfpcr(PCR_SR) & SR_EV;
-  mtpcr(sr0, PCR_SR);
-
-  extern void boot();
-  register void (*boot_p)() = &boot;
-  asm("" : "=r"(boot_p) : "0"(boot_p));
-  boot_p();
-}