Re: [Qemu-devel] [PATCH v2 6/8] loader: Support Flattened Image Trees (FIT images)

[Yongbok Kim <yongbok.kim@imgtec.com>]

On 08/09/2016 15:51, Paul Burton wrote:
> 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 <paul.burton@imgtec.com>
> ---
>  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;

Magic number. Perhaps UBOOT_MAX_GUNZIP_BYTES which is defined in the
loader.c? It would be better to move the definition to the loader.h and
reuse it here.

> +        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) {

Error messages for the consistency.

> +        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);

I guess fdt is always not compressed. Otherwise freeing uncompressed data
is required.

> +    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,
> 


Regards,
Yongbok