diff options
Diffstat (limited to 'hw/arm/boot.c')
| -rw-r--r-- | hw/arm/boot.c | 71 |
1 files changed, 65 insertions, 6 deletions
diff --git a/hw/arm/boot.c b/hw/arm/boot.c index e32f2f4158..c8dc34f086 100644 --- a/hw/arm/boot.c +++ b/hw/arm/boot.c @@ -312,7 +312,26 @@ static void set_kernel_args_old(const struct arm_boot_info *info) } } -static int load_dtb(hwaddr addr, const struct arm_boot_info *binfo) +/** + * load_dtb() - load a device tree binary image into memory + * @addr: the address to load the image at + * @binfo: struct describing the boot environment + * @addr_limit: upper limit of the available memory area at @addr + * + * Load a device tree supplied by the machine or by the user with the + * '-dtb' command line option, and put it at offset @addr in target + * memory. + * + * If @addr_limit contains a meaningful value (i.e., it is strictly greater + * than @addr), the device tree is only loaded if its size does not exceed + * the limit. + * + * Returns: the size of the device tree image on success, + * 0 if the image size exceeds the limit, + * -1 on errors. + */ +static int load_dtb(hwaddr addr, const struct arm_boot_info *binfo, + hwaddr addr_limit) { void *fdt = NULL; int size, rc; @@ -341,6 +360,15 @@ static int load_dtb(hwaddr addr, const struct arm_boot_info *binfo) } } + if (addr_limit > addr && size > (addr_limit - addr)) { + /* Installing the device tree blob at addr would exceed addr_limit. + * Whether this constitutes failure is up to the caller to decide, + * so just return 0 as size, i.e., no error. + */ + g_free(fdt); + return 0; + } + acells = qemu_fdt_getprop_cell(fdt, "/", "#address-cells"); scells = qemu_fdt_getprop_cell(fdt, "/", "#size-cells"); if (acells == 0 || scells == 0) { @@ -396,11 +424,14 @@ static int load_dtb(hwaddr addr, const struct arm_boot_info *binfo) qemu_fdt_dumpdtb(fdt, size); - cpu_physical_memory_write(addr, fdt, size); + /* Put the DTB into the memory map as a ROM image: this will ensure + * the DTB is copied again upon reset, even if addr points into RAM. + */ + rom_add_blob_fixed("dtb", fdt, size, addr); g_free(fdt); - return 0; + return size; fail: g_free(fdt); @@ -451,7 +482,7 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info) int kernel_size; int initrd_size; int is_linux = 0; - uint64_t elf_entry; + uint64_t elf_entry, elf_low_addr, elf_high_addr; int elf_machine; hwaddr entry, kernel_load_offset; int big_endian; @@ -459,6 +490,16 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info) /* Load the kernel. */ if (!info->kernel_filename) { + + 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 (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. */ @@ -508,7 +549,25 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info) /* Assume that raw images are linux kernels, and ELF images are not. */ kernel_size = load_elf(info->kernel_filename, NULL, NULL, &elf_entry, - NULL, NULL, big_endian, elf_machine, 1); + &elf_low_addr, &elf_high_addr, big_endian, + elf_machine, 1); + if (kernel_size > 0 && have_dtb(info)) { + /* If there is still some room left at the base of RAM, try and put + * the DTB there like we do for images loaded with -bios or -pflash. + */ + if (elf_low_addr > info->loader_start + || elf_high_addr < info->loader_start) { + /* Pass elf_low_addr as address limit to load_dtb if it may be + * pointing into RAM, otherwise pass '0' (no limit) + */ + if (elf_low_addr < info->loader_start) { + elf_low_addr = 0; + } + if (load_dtb(info->loader_start, info, elf_low_addr) < 0) { + exit(1); + } + } + } entry = elf_entry; if (kernel_size < 0) { kernel_size = load_uimage(info->kernel_filename, &entry, NULL, @@ -569,7 +628,7 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info) */ hwaddr dtb_start = QEMU_ALIGN_UP(info->initrd_start + initrd_size, 4096); - if (load_dtb(dtb_start, info)) { + if (load_dtb(dtb_start, info, 0) < 0) { exit(1); } fixupcontext[FIXUP_ARGPTR] = dtb_start; |