[Qemu-devel] [PATCH 5/7] loader: Support Flattened Image Trees (FIT images)

[Paul Burton]

Introduce support for loading Flattened Image Trees, as used by modern
U-Boot. FIT images are essentially flattened device tree files which
contain binary images such as kernels, FDTs or ramdisks along with one
or more configuration nodes describing boot configurations.

The MIPS Boston board typically boots kernels in the form of FIT images,
and will make use of this code.

Signed-off-by: Paul Burton <address@hidden>
---
 hw/core/Makefile.objs   |   1 +
 hw/core/loader-fit.c    | 287 ++++++++++++++++++++++++++++++++++++++++++++++++
 hw/core/loader.c        |   3 +-
 include/hw/loader-fit.h |  41 +++++++
 include/hw/loader.h     |   2 +
 5 files changed, 332 insertions(+), 2 deletions(-)
 create mode 100644 hw/core/loader-fit.c
 create mode 100644 include/hw/loader-fit.h

diff --git a/hw/core/Makefile.objs b/hw/core/Makefile.objs
index cfd4840..4adb860 100644
--- a/hw/core/Makefile.objs
+++ b/hw/core/Makefile.objs
@@ -14,6 +14,7 @@ common-obj-$(CONFIG_SOFTMMU) += sysbus.o
 common-obj-$(CONFIG_SOFTMMU) += machine.o
 common-obj-$(CONFIG_SOFTMMU) += null-machine.o
 common-obj-$(CONFIG_SOFTMMU) += loader.o
+common-obj-$(CONFIG_SOFTMMU) += loader-fit.o
 common-obj-$(CONFIG_SOFTMMU) += qdev-properties-system.o
 common-obj-$(CONFIG_SOFTMMU) += register.o
 common-obj-$(CONFIG_PLATFORM_BUS) += platform-bus.o
diff --git a/hw/core/loader-fit.c b/hw/core/loader-fit.c
new file mode 100644
index 0000000..479a7fb
--- /dev/null
+++ b/hw/core/loader-fit.c
@@ -0,0 +1,287 @@
+/*
+ * Flattened Image Tree loader.
+ *
+ * Copyright (c) 2016 Imagination Technologies
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "exec/address-spaces.h"
+#include "exec/memory.h"
+#include "hw/loader.h"
+#include "hw/loader-fit.h"
+#include "qemu/cutils.h"
+#include "qemu/error-report.h"
+#include "sysemu/device_tree.h"
+#include "sysemu/sysemu.h"
+
+#include <libfdt.h>
+#include <zlib.h>
+
+static const void *fit_load_image(const void *itb, const char *name,
+                                  int *poff, size_t *psz)
+{
+    const void *data;
+    const char *comp;
+    void *uncomp_data;
+    char path[128];
+    int off, sz;
+    ssize_t uncomp_len;
+
+    snprintf(path, sizeof(path), "/images/%s", name);
+
+    off = fdt_path_offset(itb, path);
+    if (off < 0) {
+        return NULL;
+    }
+    if (poff) {
+        *poff = off;
+    }
+
+    data = fdt_getprop(itb, off, "data", &sz);
+    if (!data) {
+        return NULL;
+    }
+
+    comp = fdt_getprop(itb, off, "compression", NULL);
+    if (!comp || !strcmp(comp, "none")) {
+        if (psz) {
+            *psz = sz;
+        }
+        return data;
+    }
+
+    if (!strcmp(comp, "gzip")) {
+        uncomp_len = 64 << 20;
+        uncomp_data = g_malloc(uncomp_len);
+
+        uncomp_len = gunzip(uncomp_data, uncomp_len, (void *)data, sz);
+        if (uncomp_len < 0) {
+            error_printf("unable to decompress %s image\n", name);
+            g_free(uncomp_data);
+            return NULL;
+        }
+
+        data = g_realloc(uncomp_data, uncomp_len);
+        if (psz) {
+            *psz = uncomp_len;
+        }
+        return data;
+    }
+
+    error_printf("unknown compression '%s'\n", comp);
+    return NULL;
+}
+
+static int fit_image_addr(const void *itb, int img, const char *name,
+                          hwaddr *addr)
+{
+    const void *prop;
+    int len;
+
+    prop = fdt_getprop(itb, img, name, &len);
+    if (!prop) {
+        return -ENOENT;
+    }
+
+    switch (len) {
+    case 4:
+        *addr = fdt32_to_cpu(*(fdt32_t *)prop);
+        return 0;
+    case 8:
+        *addr = fdt64_to_cpu(*(fdt64_t *)prop);
+        return 0;
+    default:
+        error_printf("invalid %s address length %d\n", name, len);
+        return -EINVAL;
+    }
+}
+
+static int fit_load_kernel(const struct fit_loader *ldr, const void *itb,
+                           int cfg, void *opaque, hwaddr *pend)
+{
+    const char *name;
+    const void *data;
+    hwaddr load_addr, entry_addr;
+    int img_off, err;
+    size_t sz;
+
+    name = fdt_getprop(itb, cfg, "kernel", NULL);
+    if (!name) {
+        error_printf("no kernel specified by FIT configuration\n");
+        return -EINVAL;
+    }
+
+    data = fit_load_image(itb, name, &img_off, &sz);
+    if (!data) {
+        error_printf("unable to load kernel image from FIT\n");
+        return -EINVAL;
+    }
+
+    err = fit_image_addr(itb, img_off, "load", &load_addr);
+    if (err) {
+        error_printf("unable to read kernel load address from FIT\n");
+        return err;
+    }
+
+    err = fit_image_addr(itb, img_off, "entry", &entry_addr);
+    if (err) {
+        return err;
+    }
+
+    if (ldr->kernel_filter) {
+        data = ldr->kernel_filter(opaque, data, &load_addr, &entry_addr);
+    }
+
+    if (pend) {
+        *pend = load_addr + sz;
+    }
+
+    load_addr = ldr->addr_to_phys(opaque, load_addr);
+    rom_add_blob_fixed(name, data, sz, load_addr);
+
+    return 0;
+}
+
+static int fit_load_fdt(const struct fit_loader *ldr, const void *itb,
+                        int cfg, void *opaque, const void *match_data,
+                        hwaddr kernel_end)
+{
+    const char *name;
+    const void *data;
+    hwaddr load_addr;
+    int img_off, err;
+    size_t sz;
+
+    name = fdt_getprop(itb, cfg, "fdt", NULL);
+    if (!name) {
+        return 0;
+    }
+
+    data = fit_load_image(itb, name, &img_off, &sz);
+    if (!data) {
+        error_printf("unable to load FDT image from FIT\n");
+        return -EINVAL;
+    }
+
+    err = fit_image_addr(itb, img_off, "load", &load_addr);
+    if (err == -ENOENT) {
+        load_addr = ROUND_UP(kernel_end, 64 * K_BYTE) + (10 * M_BYTE);
+    } else if (err) {
+        return err;
+    }
+
+    if (ldr->fdt_filter) {
+        data = ldr->fdt_filter(opaque, data, match_data, &load_addr);
+    }
+
+    load_addr = ldr->addr_to_phys(opaque, load_addr);
+    sz = fdt_totalsize(data);
+    rom_add_blob_fixed(name, data, sz, load_addr);
+
+    return 0;
+}
+
+static bool fit_cfg_compatible(const void *itb, int cfg, const char *compat)
+{
+    const void *fdt;
+    const char *fdt_name;
+
+    fdt_name = fdt_getprop(itb, cfg, "fdt", NULL);
+    if (!fdt_name) {
+        return false;
+    }
+
+    fdt = fit_load_image(itb, fdt_name, NULL, NULL);
+    if (!fdt) {
+        return false;
+    }
+
+    if (fdt_check_header(fdt)) {
+        return false;
+    }
+
+    if (fdt_node_check_compatible(fdt, 0, compat)) {
+        return false;
+    }
+
+    return true;
+}
+
+int load_fit(const struct fit_loader *ldr, const char *filename, void *opaque)
+{
+    const struct fit_loader_match *match;
+    const void *itb, *match_data = NULL;
+    const char *def_cfg_name;
+    char path[128];
+    int itb_size, configs, cfg_off, off, err;
+    hwaddr kernel_end;
+
+    itb = load_device_tree(filename, &itb_size);
+    if (!itb) {
+        return -EINVAL;
+    }
+
+    configs = fdt_path_offset(itb, "/configurations");
+    if (configs < 0) {
+        return configs;
+    }
+
+    cfg_off = -FDT_ERR_NOTFOUND;
+
+    if (ldr->matches) {
+        for (match = ldr->matches; match->compatible; match++) {
+            off = fdt_first_subnode(itb, configs);
+            while (off >= 0) {
+                if (fit_cfg_compatible(itb, off, match->compatible)) {
+                    cfg_off = off;
+                    match_data = match->data;
+                    break;
+                }
+
+                off = fdt_next_subnode(itb, off);
+            }
+
+            if (cfg_off >= 0) {
+                break;
+            }
+        }
+    }
+
+    if (cfg_off < 0) {
+        def_cfg_name = fdt_getprop(itb, configs, "default", NULL);
+        if (def_cfg_name) {
+            snprintf(path, sizeof(path), "/configurations/%s", def_cfg_name);
+            cfg_off = fdt_path_offset(itb, path);
+        }
+    }
+
+    if (cfg_off < 0) {
+        /* couldn't find a configuration to use */
+        return cfg_off;
+    }
+
+    err = fit_load_kernel(ldr, itb, cfg_off, opaque, &kernel_end);
+    if (err) {
+        return err;
+    }
+
+    err = fit_load_fdt(ldr, itb, cfg_off, opaque, match_data, kernel_end);
+    if (err) {
+        return err;
+    }
+
+    return 0;
+}
diff --git a/hw/core/loader.c b/hw/core/loader.c
index 53e0e41..54a5189 100644
--- a/hw/core/loader.c
+++ b/hw/core/loader.c
@@ -513,8 +513,7 @@ static void zfree(void *x, void *addr)
  * overflow on real hardware too. */
 #define UBOOT_MAX_GUNZIP_BYTES (64 << 20)
 
-static ssize_t gunzip(void *dst, size_t dstlen, uint8_t *src,
-                      size_t srclen)
+ssize_t gunzip(void *dst, size_t dstlen, uint8_t *src, size_t srclen)
 {
     z_stream s;
     ssize_t dstbytes;
diff --git a/include/hw/loader-fit.h b/include/hw/loader-fit.h
new file mode 100644
index 0000000..9e2a068
--- /dev/null
+++ b/include/hw/loader-fit.h
@@ -0,0 +1,41 @@
+/*
+ * Flattened Image Tree loader.
+ *
+ * Copyright (c) 2016 Imagination Technologies
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef HW_LOADER_FIT_H
+#define HW_LOADER_FIT_H
+
+#include <exec/hwaddr.h>
+
+struct fit_loader_match {
+    const char *compatible;
+    const void *data;
+};
+
+struct fit_loader {
+    const struct fit_loader_match *matches;
+    hwaddr (*addr_to_phys)(void *opaque, uint64_t addr);
+    const void *(*fdt_filter)(void *opaque, const void *fdt,
+                              const void *match_data, hwaddr *load_addr);
+    const void *(*kernel_filter)(void *opaque, const void *kernel,
+                                 hwaddr *load_addr, hwaddr *entry_addr);
+};
+
+int load_fit(const struct fit_loader *ldr, const char *filename, void *opaque);
+
+#endif /* HW_LOADER_FIT_H */
diff --git a/include/hw/loader.h b/include/hw/loader.h
index 4879b63..ed8d6e0 100644
--- a/include/hw/loader.h
+++ b/include/hw/loader.h
@@ -107,6 +107,8 @@ int load_uimage(const char *filename, hwaddr *ep,
  */
 int load_ramdisk(const char *filename, hwaddr addr, uint64_t max_sz);
 
+ssize_t gunzip(void *dst, size_t dstlen, uint8_t *src, size_t srclen);
+
 ssize_t read_targphys(const char *name,
                       int fd, hwaddr dst_addr, size_t nbytes);
 void pstrcpy_targphys(const char *name,
-- 
2.9.3