Implement device tree support needed for Bamboo emulation

To implement the -kernel, -initrd, and -append options, 4xx board emulation
must load the guest kernel as if firmware had loaded it. Where u-boot would be
the firmware, we must load the flat device tree into memory and set key fields
such as /chosen/bootargs.

This patch introduces a dependency on libfdt for flat device tree support.

Signed-off-by: Hollis Blanchard <[email protected]>
Signed-off-by: Aurelien Jarno <[email protected]>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6064 c046a42c-6fe2-441c-8c8c-71466251a162

Makefile.target

@@ -655,6 +655,10 @@ OBJS+= heathrow_pic.o grackle_pci.o ppc_oldworld.o
 OBJS+= unin_pci.o ppc_chrp.o
 # PowerPC 4xx boards
 OBJS+= pflash_cfi02.o ppc4xx_devs.o ppc4xx_pci.o ppc405_uc.o ppc405_boards.o
+ifdef FDT_LIBS
+OBJS+= device_tree.o
+LIBS+= $(FDT_LIBS)
+endif
 # virtio support
 OBJS+= virtio.o virtio-blk.o virtio-balloon.o
 endif

configure

@@ -119,6 +119,7 @@ kvm="yes"
 kerneldir=""
 aix="no"
 blobs="yes"
+fdt="yes"
 
 # OS specific
 targetos=`uname -s`
@@ -966,6 +967,18 @@ if $cc $ARCH_CFLAGS -o $TMPE $TMPC > /dev/null 2> /dev/null ; then
   iovec=yes
 fi
 
+##########################################
+# fdt probe
+if test "$fdt" = "yes" ; then
+    fdt=no
+    cat > $TMPC << EOF
+int main(void) { return 0; }
+EOF
+  if $cc $ARCH_CFLAGS -o $TMPE ${OS_CFLAGS} $TMPC -lfdt 2> /dev/null ; then
+    fdt=yes
+  fi
+fi
+
 # Check if tools are available to build documentation.
 if [ -x "`which texi2html 2>/dev/null`" ] && \
    [ -x "`which pod2man 2>/dev/null`" ]; then
@@ -1061,6 +1074,7 @@ echo "vde support       $vde"
 echo "AIO support       $aio"
 echo "Install blobs     $blobs"
 echo "KVM support       $kvm"
+echo "fdt support       $fdt"
 
 if test $sdl_too_old = "yes"; then
 echo "-> Your SDL version is too old - please upgrade to have SDL support"
@@ -1350,6 +1364,10 @@ fi
 if test "$iovec" = "yes" ; then
   echo "#define HAVE_IOVEC 1" >> $config_h
 fi
+if test "$fdt" = "yes" ; then
+  echo "#define HAVE_FDT 1" >> $config_h
+  echo "FDT_LIBS=-lfdt" >> $config_mak
+fi
 
 # XXX: suppress that
 if [ "$bsd" = "yes" ] ; then

device_tree.c

@@ -0,0 +1,114 @@
+/*
+ * Functions to help device tree manipulation using libfdt.
+ * It also provides functions to read entries from device tree proc
+ * interface.
+ *
+ * Copyright 2008 IBM Corporation.
+ * Authors: Jerone Young <[email protected]>
+ *          Hollis Blanchard <[email protected]>
+ *
+ * This work is licensed under the GNU GPL license version 2 or later.
+ *
+ */
+
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+#include "config.h"
+#include "qemu-common.h"
+#include "sysemu.h"
+#include "device_tree.h"
+
+#include <libfdt.h>
+
+void *load_device_tree(const char *filename_path, void *load_addr)
+{
+    int dt_file_size;
+    int dt_file_load_size;
+    int new_dt_size;
+    int ret;
+    void *dt_file = NULL;
+    void *fdt;
+
+    dt_file_size = get_image_size(filename_path);
+    if (dt_file_size < 0) {
+        printf("Unable to get size of device tree file '%s'\n",
+            filename_path);
+        goto fail;
+    }
+
+    /* First allocate space in qemu for device tree */
+    dt_file = qemu_mallocz(dt_file_size);
+    if (dt_file == NULL) {
+        printf("Unable to allocate memory in qemu for device tree\n");
+        goto fail;
+    }
+
+    dt_file_load_size = load_image(filename_path, dt_file);
+
+    /* Second we place new copy of 2x size in guest memory
+     * This give us enough room for manipulation.
+     */
+    new_dt_size = dt_file_size * 2;
+
+    fdt = load_addr;
+    ret = fdt_open_into(dt_file, fdt, new_dt_size);
+    if (ret) {
+        printf("Unable to copy device tree in memory\n");
+        goto fail;
+    }
+
+    /* Check sanity of device tree */
+    if (fdt_check_header(fdt)) {
+        printf ("Device tree file loaded into memory is invalid: %s\n",
+            filename_path);
+        goto fail;
+    }
+    /* free qemu memory with old device tree */
+    qemu_free(dt_file);
+    return fdt;
+
+fail:
+    qemu_free(dt_file);
+    return NULL;
+}
+
+int qemu_devtree_setprop(void *fdt, const char *node_path,
+                         const char *property, uint32_t *val_array, int size)
+{
+    int offset;
+
+    offset = fdt_path_offset(fdt, node_path);
+    if (offset < 0)
+        return offset;
+
+    return fdt_setprop(fdt, offset, property, val_array, size);
+}
+
+int qemu_devtree_setprop_cell(void *fdt, const char *node_path,
+                              const char *property, uint32_t val)
+{
+    int offset;
+
+    offset = fdt_path_offset(fdt, node_path);
+    if (offset < 0)
+        return offset;
+
+    return fdt_setprop_cell(fdt, offset, property, val);
+}
+
+int qemu_devtree_setprop_string(void *fdt, const char *node_path,
+                                const char *property, const char *string)
+{
+    int offset;
+
+    offset = fdt_path_offset(fdt, node_path);
+    if (offset < 0)
+        return offset;
+
+    return fdt_setprop_string(fdt, offset, property, string);
+}

device_tree.h

@@ -0,0 +1,26 @@
+/*
+ * Header with function prototypes to help device tree manipulation using
+ * libfdt. It also provides functions to read entries from device tree proc
+ * interface.
+ *
+ * Copyright 2008 IBM Corporation.
+ * Authors: Jerone Young <[email protected]>
+ *          Hollis Blanchard <[email protected]>
+ *
+ * This work is licensed under the GNU GPL license version 2 or later.
+ *
+ */
+
+#ifndef __DEVICE_TREE_H__
+#define __DEVICE_TREE_H__
+
+void *load_device_tree(const char *filename_path, void *load_addr);
+
+int qemu_devtree_setprop(void *fdt, const char *node_path,
+                         const char *property, uint32_t *val_array, int size);
+int qemu_devtree_setprop_cell(void *fdt, const char *node_path,
+                              const char *property, uint32_t val);
+int qemu_devtree_setprop_string(void *fdt, const char *node_path,
+                                const char *property, const char *string);
+
+#endif /* __DEVICE_TREE_H__ */

libfdt_env.h

@@ -0,0 +1,41 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright IBM Corp. 2008
+ * Authors: Hollis Blanchard <[email protected]>
+ *
+ */
+
+#ifndef _LIBFDT_ENV_H
+#define _LIBFDT_ENV_H
+
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+#include <endian.h>
+#include <byteswap.h>
+
+#if __BYTE_ORDER == __BIG_ENDIAN
+#define fdt32_to_cpu(x)		(x)
+#define cpu_to_fdt32(x)		(x)
+#define fdt64_to_cpu(x)		(x)
+#define cpu_to_fdt64(x)		(x)
+#else
+#define fdt32_to_cpu(x)		(bswap_32((x)))
+#define cpu_to_fdt32(x)		(bswap_32((x)))
+#define fdt64_to_cpu(x)		(bswap_64((x)))
+#define cpu_to_fdt64(x)		(bswap_64((x)))
+#endif
+
+#endif /* _LIBFDT_ENV_H */