On 12.12.14 16:58, Laszlo Ersek wrote:
> Introduce the new boolean field "arm_boot_info.firmware_loaded". When this
> field is set, it means that the portion of guest DRAM that the VCPU
> normally starts to execute, or the pflash chip that the VCPU normally
> starts to execute, has been populated by board-specific code with
> full-fledged guest firmware code, before the board calls
> arm_load_kernel().
>
> Simultaneously, "arm_boot_info.firmware_loaded" guarantees that the board
> code has set up the global firmware config instance, for arm_load_kernel()
> to find with fw_cfg_find().
>
> Guest kernel (-kernel) and guest firmware (-bios, -pflash) has always been
> possible to specify independently on the command line. The following cases
> should be considered:
>
> nr -bios -pflash -kernel description
> unit#0
> -- ------- ------- ------- -------------------------------------------
> 1 present present absent Board code rejects this case, -bios and
> present present present -pflash unit#0 are exclusive. Left intact
> by this patch.
>
> 2 absent absent present Traditional kernel loading, with qemu's
> minimal board firmware. Left intact by this
> patch.
>
> 3 absent present absent Preexistent case for booting guest firmware
> present absent absent loaded with -bios or -pflash. Left intact
> by this patch.
>
> 4 absent absent absent Preexistent case for not loading any
> firmware or kernel up-front. Left intact by
> this patch.
>
> 5 present absent present New case introduced by this patch: kernel
> absent present present image is passed to externally loaded
> firmware in unmodified form, using fw_cfg.
>
> An easy way to see that this patch doesn't interfere with existing cases
> is to realize that "info->firmware_loaded" is constant zero at this point.
> Which makes the "outer" condition unchanged, and the "inner" condition
> (with the fw_cfg-related code) dead.
>
> Signed-off-by: Laszlo Ersek <ler...@redhat.com>
> Reviewed-by: Peter Maydell <peter.mayd...@linaro.org>
> ---
>
> Notes:
> v4:
> - drop space "between function name and open parenthesis '('" [Peter]
>
> v3:
> - unchanged
>
> include/hw/arm/arm.h | 5 +++
> hw/arm/boot.c | 91
> +++++++++++++++++++++++++++++++++++++++++++++++++---
> 2 files changed, 91 insertions(+), 5 deletions(-)
>
> diff --git a/include/hw/arm/arm.h b/include/hw/arm/arm.h
> index cefc9e6..dd69d66 100644
> --- a/include/hw/arm/arm.h
> +++ b/include/hw/arm/arm.h
> @@ -65,8 +65,13 @@ struct arm_boot_info {
> int is_linux;
> hwaddr initrd_start;
> hwaddr initrd_size;
> hwaddr entry;
> +
> + /* Boot firmware has been loaded, typically at address 0, with -bios or
> + * -pflash. It also implies that fw_cfg_find() will succeed.
> + */
> + bool firmware_loaded;
> };
> void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info);
>
> /* Multiplication factor to convert from system clock ticks to qemu timer
> diff --git a/hw/arm/boot.c b/hw/arm/boot.c
> index e6a3c5b..5c65d16 100644
> --- a/hw/arm/boot.c
> +++ b/hw/arm/boot.c
> @@ -477,8 +477,62 @@ static void do_cpu_reset(void *opaque)
> }
> }
> }
>
> +/**
> + * load_image_to_fw_cfg() - Load an image file into an fw_cfg entry
> identified
> + * by key.
> + * @fw_cfg: The firmware config instance to store the data in.
> + * @size_key: The firmware config key to store the size of the loaded data
> + * under, with fw_cfg_add_i32().
> + * @data_key: The firmware config key to store the loaded data under, with
> + * fw_cfg_add_bytes().
> + * @image_name: The name of the image file to load. If it is NULL, the
> function
> + * returns without doing anything.
> + * @decompress: Whether the image should be decompressed (gunzipped) before
> + * adding it to fw_cfg.
> + *
> + * In case of failure, the function prints an error message to stderr and the
> + * process exits with status 1.
> + */
> +static void load_image_to_fw_cfg(FWCfgState *fw_cfg, uint16_t size_key,
> + uint16_t data_key, const char *image_name,
> + bool decompress)
> +{
> + size_t size;
> + uint8_t *data;
> +
> + if (image_name == NULL) {
> + return;
> + }
> +
> + if (decompress) {
> + int bytes;
> +
> + bytes = load_image_gzipped_buffer(image_name,
> + LOAD_IMAGE_MAX_GUNZIP_BYTES,
> &data);
> + if (bytes == -1) {
> + fprintf(stderr, "failed to load and decompress \"%s\"\n",
> + image_name);
> + exit(1);
> + }
> + size = bytes;
> + } else {
> + gchar *contents;
> + gsize length;
> +
> + if (!g_file_get_contents(image_name, &contents, &length, NULL)) {
> + fprintf(stderr, "failed to load \"%s\"\n", image_name);
> + exit(1);
> + }
> + size = length;
> + data = (uint8_t *)contents;
> + }
> +
> + fw_cfg_add_i32(fw_cfg, size_key, size);
> + fw_cfg_add_bytes(fw_cfg, data_key, data, size);
> +}
> +
> void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
> {
> CPUState *cs;
> int kernel_size;
> @@ -499,21 +553,48 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info
> *info)
> qemu_register_reset(do_cpu_reset, ARM_CPU(cs));
> }
>
> /* Load the kernel. */
> - if (!info->kernel_filename) {
> + if (!info->kernel_filename || info->firmware_loaded) {
>
> if (have_dtb(info)) {
> - /* If we have a device tree blob, but no kernel to supply it to,
> - * copy it to the base of RAM for a bootloader to pick up.
> + /* If we have a device tree blob, but no kernel to supply it to
> (or
> + * the kernel is supposed to be loaded by the bootloader), copy
> the
> + * DTB to the base of RAM for the bootloader to pick up.
> */
> if (load_dtb(info->loader_start, info, 0) < 0) {
> exit(1);
> }
> }
>
> - /* If no kernel specified, do nothing; we will start from address 0
> - * (typically a boot ROM image) in the same way as hardware.
> + if (info->kernel_filename) {
> + FWCfgState *fw_cfg;
> + bool decompress_kernel;
> +
> + fw_cfg = fw_cfg_find();
> + decompress_kernel = arm_feature(&cpu->env, ARM_FEATURE_AARCH64);
I don't understand this. On AArch64 I can simply do -kernel Image and it
boots without decompressing anything, no?
Alex
