[OpenBIOS] [PATCHv2 07/25] SPARC32: introduce arch_init_program() implementation

[Mark Cave-Ayland]

And switch start_elf() over to use it.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland at ilande.co.uk>
---
 arch/sparc32/context.c |   27 ++++++++++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/arch/sparc32/context.c b/arch/sparc32/context.c
index 50b9edf..0a5b370 100644
--- a/arch/sparc32/context.c
+++ b/arch/sparc32/context.c
@@ -6,6 +6,8 @@
 #include "config.h"
 #include "kernel/kernel.h"
 #include "context.h"
+#include "libopenbios/bindings.h"
+#include "libopenbios/initprogram.h"
 #include "libopenbios/sys_info.h"
 #include "boot.h"
 #include "openbios.h"
@@ -63,6 +65,8 @@ static void start_main(void)
     __context = boot_ctx;
 }
 
+#define CTX_OFFSET(n) (sizeof(struct context) + n * sizeof(uint32_t))
+
 /* Setup a new context using the given stack.
  */
 struct context *
@@ -71,7 +75,7 @@ init_context(uint8_t *stack, uint32_t stack_size, int num_params)
     struct context *ctx;
 
     ctx = (struct context *)
-	(stack + stack_size - (sizeof(*ctx) + num_params*sizeof(uint32_t)));
+	(stack + stack_size - CTX_OFFSET(num_params));
     /* Use valid window state from startup */
     memcpy(ctx, &main_ctx, sizeof(struct context));
 
@@ -82,6 +86,24 @@ init_context(uint8_t *stack, uint32_t stack_size, int num_params)
     return ctx;
 }
 
+/* init-program */
+int
+arch_init_program(void)
+{
+    volatile struct context *ctx = __context;
+    ucell entry;
+
+    ctx->regs[REG_O0] = (unsigned long)romvec;
+    ctx->regs[REG_SP] = (unsigned long)malloc(IMAGE_STACK_SIZE) + IMAGE_STACK_SIZE - CTX_OFFSET(1);
+
+    /* Set entry point */
+    feval("load-state >ls.entry @");
+    entry = POP();
+    ctx->pc = entry;
+
+    return 0;
+}
+
 /* Switch to another context. */
 struct context *switch_to(struct context *ctx)
 {
@@ -111,8 +133,7 @@ unsigned int start_elf(unsigned long entry_point, unsigned long param)
 {
     struct context *ctx = client_ctx;
 
-    ctx->pc = entry_point;
-    ctx->regs[REG_O0] = param;
+    arch_init_program();
 
     ctx = switch_to(ctx);
     return ctx->regs[REG_O0];
-- 
1.7.10.4