diff --git a/hw/arm-misc.h b/hw/arm-misc.h index d02f7f08c8..adb166586b 100644 --- a/hw/arm-misc.h +++ b/hw/arm-misc.h @@ -56,6 +56,7 @@ struct arm_boot_info { const struct arm_boot_info *info); /* Used internally by arm_boot.c */ int is_linux; + hwaddr initrd_start; hwaddr initrd_size; hwaddr entry; }; diff --git a/hw/arm_boot.c b/hw/arm_boot.c index 09bf6c5cdc..92e2cab476 100644 --- a/hw/arm_boot.c +++ b/hw/arm_boot.c @@ -18,7 +18,6 @@ #define KERNEL_ARGS_ADDR 0x100 #define KERNEL_LOAD_ADDR 0x00010000 -#define INITRD_LOAD_ADDR 0x00d00000 /* The worlds second smallest bootloader. Set r0-r2, then jump to kernel. */ static uint32_t bootloader[] = { @@ -109,7 +108,7 @@ static void set_kernel_args(const struct arm_boot_info *info) /* ATAG_INITRD2 */ WRITE_WORD(p, 4); WRITE_WORD(p, 0x54420005); - WRITE_WORD(p, info->loader_start + INITRD_LOAD_ADDR); + WRITE_WORD(p, info->initrd_start); WRITE_WORD(p, initrd_size); } if (info->kernel_cmdline && *info->kernel_cmdline) { @@ -185,10 +184,11 @@ static void set_kernel_args_old(const struct arm_boot_info *info) /* pages_in_vram */ WRITE_WORD(p, 0); /* initrd_start */ - if (initrd_size) - WRITE_WORD(p, info->loader_start + INITRD_LOAD_ADDR); - else + if (initrd_size) { + WRITE_WORD(p, info->initrd_start); + } else { WRITE_WORD(p, 0); + } /* initrd_size */ WRITE_WORD(p, initrd_size); /* rd_start */ @@ -281,14 +281,13 @@ static int load_dtb(hwaddr addr, const struct arm_boot_info *binfo) if (binfo->initrd_size) { rc = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-start", - binfo->loader_start + INITRD_LOAD_ADDR); + binfo->initrd_start); if (rc < 0) { fprintf(stderr, "couldn't set /chosen/linux,initrd-start\n"); } rc = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-end", - binfo->loader_start + INITRD_LOAD_ADDR + - binfo->initrd_size); + binfo->initrd_start + binfo->initrd_size); if (rc < 0) { fprintf(stderr, "couldn't set /chosen/linux,initrd-end\n"); } @@ -375,6 +374,19 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info) big_endian = 0; #endif + /* We want to put the initrd far enough into RAM that when the + * kernel is uncompressed it will not clobber the initrd. However + * on boards without much RAM we must ensure that we still leave + * enough room for a decent sized initrd, and on boards with large + * amounts of RAM we must avoid the initrd being so far up in RAM + * that it is outside lowmem and inaccessible to the kernel. + * So for boards with less than 256MB of RAM we put the initrd + * halfway into RAM, and for boards with 256MB of RAM or more we put + * the initrd at 128MB. + */ + info->initrd_start = info->loader_start + + MIN(info->ram_size / 2, 128 * 1024 * 1024); + /* 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); @@ -398,10 +410,9 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info) if (is_linux) { if (info->initrd_filename) { initrd_size = load_image_targphys(info->initrd_filename, - info->loader_start - + INITRD_LOAD_ADDR, - info->ram_size - - INITRD_LOAD_ADDR); + info->initrd_start, + info->ram_size - + info->initrd_start); if (initrd_size < 0) { fprintf(stderr, "qemu: could not load initrd '%s'\n", info->initrd_filename); @@ -419,9 +430,8 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info) */ if (info->dtb_filename) { /* Place the DTB after the initrd in memory */ - hwaddr dtb_start = TARGET_PAGE_ALIGN(info->loader_start - + INITRD_LOAD_ADDR - + initrd_size); + hwaddr dtb_start = TARGET_PAGE_ALIGN(info->initrd_start + + initrd_size); if (load_dtb(dtb_start, info)) { exit(1); }