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Diffstat (limited to 'qemu/roms/openbios/arch/sparc64/context.c')
-rw-r--r--qemu/roms/openbios/arch/sparc64/context.c129
1 files changed, 129 insertions, 0 deletions
diff --git a/qemu/roms/openbios/arch/sparc64/context.c b/qemu/roms/openbios/arch/sparc64/context.c
new file mode 100644
index 000000000..2e7668958
--- /dev/null
+++ b/qemu/roms/openbios/arch/sparc64/context.c
@@ -0,0 +1,129 @@
+/*
+ * context switching
+ * 2003-10 by SONE Takeshi
+ */
+
+#include "config.h"
+#include "kernel/kernel.h"
+#include "context.h"
+#include "libopenbios/sys_info.h"
+#include "boot.h"
+#include "openbios.h"
+
+#define MAIN_STACK_SIZE 16384
+#define IMAGE_STACK_SIZE 4096*4
+
+#define debug printk
+
+static void start_main(void); /* forward decl. */
+void __exit_context(void); /* assembly routine */
+
+/*
+ * Main context structure
+ * It is placed at the bottom of our stack, and loaded by assembly routine
+ * to start us up.
+ */
+static struct context main_ctx = {
+ .regs[REG_SP] = (uint64_t) &_estack - STACK_BIAS - 96,
+ .pc = (uint64_t) start_main,
+ .npc = (uint64_t) start_main + 4,
+ .return_addr = (uint64_t) __exit_context,
+};
+
+/* This is used by assembly routine to load/store the context which
+ * it is to switch/switched. */
+struct context * volatile __context = &main_ctx;
+
+/* Stack for loaded ELF image */
+static uint8_t image_stack[IMAGE_STACK_SIZE];
+
+/* Pointer to startup context (physical address) */
+unsigned long __boot_ctx;
+
+/*
+ * Main starter
+ * This is the C function that runs first.
+ */
+static void start_main(void)
+{
+ /* Save startup context, so we can refer to it later.
+ * We have to keep it in physical address since we will relocate. */
+ __boot_ctx = virt_to_phys(__context);
+
+ /* Start the real fun */
+ openbios();
+
+ /* Returning from here should jump to __exit_context */
+ __context = boot_ctx;
+}
+
+static uint64_t ALIGN_SIZE(uint64_t x, uint64_t a)
+{
+ return (x + a - 1) & ~(a-1);
+}
+
+/* Setup a new context using the given stack.
+ */
+struct context *
+init_context(uint8_t *stack, uint64_t stack_size, int num_params)
+{
+ struct context *ctx;
+ uint8_t *stack_top = stack + stack_size;
+
+ ctx = (struct context *)
+ (stack_top - ALIGN_SIZE(sizeof(*ctx) + num_params*sizeof(uint64_t), sizeof(uint64_t)));
+ memset(ctx, 0, sizeof(*ctx));
+
+ /* Fill in reasonable default for flat memory model */
+ ctx->regs[REG_SP] = virt_to_phys(stack_top - STACK_BIAS - 192);
+ ctx->return_addr = virt_to_phys(__exit_context);
+
+ return ctx;
+}
+
+/* Switch to another context. */
+struct context *switch_to(struct context *ctx)
+{
+ struct context *save, *ret;
+
+ debug("switching to new context: entry point %#llx stack 0x%016llx\n", ctx->pc, ctx->regs[REG_SP]);
+ save = __context;
+ __context = ctx;
+ //asm ("pushl %cs; call __switch_context");
+ asm ("call __switch_context_nosave; nop");
+ ret = __context;
+ __context = save;
+ return ret;
+}
+
+/* Start ELF Boot image */
+uint64_t start_elf(uint64_t entry_point, uint64_t param)
+{
+ struct context *ctx;
+
+ ctx = init_context(image_stack, sizeof image_stack, 1);
+ ctx->pc = entry_point;
+ ctx->param[0] = param;
+ //ctx->eax = 0xe1fb007;
+ //ctx->ebx = param;
+
+ ctx = switch_to(ctx);
+ //return ctx->eax;
+ return 0;
+}
+
+/* Start client image */
+uint64_t start_client_image(uint64_t entry_point, uint64_t cif_handler)
+{
+ struct context *ctx;
+
+ ctx = init_context(image_stack, sizeof image_stack, 0);
+ ctx->pc = entry_point;
+ ctx->npc = entry_point+4;
+ ctx->regs[REG_O0] = 0;
+ ctx->regs[REG_O0+4] = cif_handler;
+
+ ctx = switch_to(ctx);
+
+ return 0;
+}