Add submodule dependency filesHEADmaster

Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec

1 files changed, 106 insertions, 0 deletions

diff --git a/roms/openbios/libopenbios/prep_load.c b/roms/openbios/libopenbios/prep_load.c
new file mode 100644
index 000000000..7942804bf
--- /dev/null
+++ b/roms/openbios/libopenbios/prep_load.c
@@ -0,0 +1,106 @@
+/*
+ * PReP boot partition loader
+ * Written by Mark Cave-Ayland 2018
+ */
+
+#include "config.h"
+#include "kernel/kernel.h"
+#include "libopenbios/bindings.h"
+#include "libopenbios/prep_load.h"
+#include "libopenbios/initprogram.h"
+#include "libopenbios/sys_info.h"
+#include "libc/byteorder.h"
+#include "libc/diskio.h"
+#include "drivers/drivers.h"
+#define printf printk
+#define debug printk
+
+
+int
+prep_load(ihandle_t dev)
+{
+    int retval = LOADER_NOT_SUPPORT, fd, count, size;
+    ucell *loadbase;
+    unsigned char *image;
+    uint32_t entry_point_offset, load_image_length;
+    unsigned long entry;
+
+    /* Mark the saved-program-state as invalid */
+    feval("0 state-valid !");
+
+    fd = open_ih(dev);
+    if (fd == -1) {
+        goto out;
+    }
+
+    /* Default to loading at load-base */
+    fword("load-base");
+    loadbase = cell2pointer(POP());
+
+    /* Read block 2 containing the boot info */
+    seek_io(fd, 512);
+    count = read_io(fd, (void *)loadbase, 512);
+    if (count != 512) {
+        goto out;
+    }
+
+    entry_point_offset = __le32_to_cpu(loadbase[0]);
+    load_image_length = __le32_to_cpu(loadbase[1]);
+
+    /* Load the entire image */
+    size = 0;
+    image = (unsigned char *)loadbase;
+    entry = (uintptr_t)loadbase + entry_point_offset;
+
+    seek_io(fd, 0);
+    while (size < load_image_length) {
+        count = read_io(fd, (void *)image, 512);
+        if (count == -1) {
+            break;
+        }
+
+        size += count;
+        image += count;
+    }
+
+    /* If we didn't read anything, something went wrong */
+    if (!size) {
+        goto out;
+    }
+
+    /* Set correct size */
+    size = load_image_length;
+
+    /* Initialise load-state */
+    PUSH(entry);
+    feval("load-state >ls.entry !");
+    PUSH(size);
+    feval("load-state >ls.file-size !");
+    feval("prep load-state >ls.file-type !");
+
+out:
+    close_io(fd);
+    return retval;
+}
+
+int
+is_prep(char *addr)
+{
+    /* PReP bootloaders are executed directly. So we'll say that something is
+     * PReP if the loader detected the PReP type sucessfully */
+    ucell filetype;
+
+    feval("load-state >ls.file-type @");
+    filetype = POP();
+
+    return (filetype == 0x13);
+}
+
+void
+prep_init_program(void)
+{
+    /* Entry point is already set, just need to setup the context */
+    arch_init_program();
+
+    feval("-1 state-valid !");
+}