From 337270b2a5b7e23fd595aaf22a789bf3194887cd Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= Date: Fri, 17 Dec 2021 17:57:17 +0100 Subject: [PATCH] ppc/ppc405: Fix boot from kernel MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The machine can already boot with kernel and initrd U-boot images if a firmware is loaded first. Adapt and improve the load sequence to let the machine boot directly from a Linux kernel ELF image and a usual initrd image if a firmware image is not provided. For that, install a custom CPU reset handler to setup the registers and to start the CPU from the Linux kernel entry point. Signed-off-by: Cédric Le Goater Message-Id: <20211206103712.1866296-12-clg@kaod.org> Signed-off-by: Cédric Le Goater --- hw/ppc/ppc405_boards.c | 145 +++++++++++++++++++++++++++++------------ 1 file changed, 102 insertions(+), 43 deletions(-) diff --git a/hw/ppc/ppc405_boards.c b/hw/ppc/ppc405_boards.c index 71a652e2d8..3ae2b36373 100644 --- a/hw/ppc/ppc405_boards.c +++ b/hw/ppc/ppc405_boards.c @@ -41,6 +41,7 @@ #include "qemu/error-report.h" #include "hw/loader.h" #include "qemu/cutils.h" +#include "elf.h" #define BIOS_FILENAME "ppc405_rom.bin" #define BIOS_SIZE (2 * MiB) @@ -136,25 +137,101 @@ static void ref405ep_fpga_init(MemoryRegion *sysmem, uint32_t base) qemu_register_reset(&ref405ep_fpga_reset, fpga); } +/* + * CPU reset handler when booting directly from a loaded kernel + */ +static struct boot_info { + uint32_t entry; + uint32_t bdloc; + uint32_t initrd_base; + uint32_t initrd_size; + uint32_t cmdline_base; + uint32_t cmdline_size; +} boot_info; + +static void main_cpu_reset(void *opaque) +{ + PowerPCCPU *cpu = opaque; + CPUPPCState *env = &cpu->env; + struct boot_info *bi = env->load_info; + + cpu_reset(CPU(cpu)); + + /* stack: top of sram */ + env->gpr[1] = PPC405EP_SRAM_BASE + PPC405EP_SRAM_SIZE - 8; + + /* Tune our boot state */ + env->gpr[3] = bi->bdloc; + env->gpr[4] = bi->initrd_base; + env->gpr[5] = bi->initrd_base + bi->initrd_size; + env->gpr[6] = bi->cmdline_base; + env->gpr[7] = bi->cmdline_size; + + env->nip = bi->entry; +} + +static void boot_from_kernel(MachineState *machine, PowerPCCPU *cpu) +{ + CPUPPCState *env = &cpu->env; + hwaddr boot_entry; + hwaddr kernel_base; + int kernel_size; + hwaddr initrd_base; + int initrd_size; + ram_addr_t bdloc; + int len; + + bdloc = ppc405_set_bootinfo(env, machine->ram_size); + boot_info.bdloc = bdloc; + + kernel_size = load_elf(machine->kernel_filename, NULL, NULL, NULL, + &boot_entry, &kernel_base, NULL, NULL, + 1, PPC_ELF_MACHINE, 0, 0); + if (kernel_size < 0) { + error_report("Could not load kernel '%s' : %s", + machine->kernel_filename, load_elf_strerror(kernel_size)); + exit(1); + } + boot_info.entry = boot_entry; + + /* load initrd */ + if (machine->initrd_filename) { + initrd_base = INITRD_LOAD_ADDR; + initrd_size = load_image_targphys(machine->initrd_filename, initrd_base, + machine->ram_size - initrd_base); + if (initrd_size < 0) { + error_report("could not load initial ram disk '%s'", + machine->initrd_filename); + exit(1); + } + + boot_info.initrd_base = initrd_base; + boot_info.initrd_size = initrd_size; + } + + if (machine->kernel_cmdline) { + len = strlen(machine->kernel_cmdline); + bdloc -= ((len + 255) & ~255); + cpu_physical_memory_write(bdloc, machine->kernel_cmdline, len + 1); + boot_info.cmdline_base = bdloc; + boot_info.cmdline_size = bdloc + len; + } + + /* Install our custom reset handler to start from Linux */ + qemu_register_reset(main_cpu_reset, cpu); + env->load_info = &boot_info; +} + static void ref405ep_init(MachineState *machine) { MachineClass *mc = MACHINE_GET_CLASS(machine); const char *kernel_filename = machine->kernel_filename; - const char *kernel_cmdline = machine->kernel_cmdline; - const char *initrd_filename = machine->initrd_filename; PowerPCCPU *cpu; - CPUPPCState *env; DeviceState *dev; SysBusDevice *s; MemoryRegion *sram = g_new(MemoryRegion, 1); - ram_addr_t bdloc; MemoryRegion *ram_memories = g_new(MemoryRegion, 2); hwaddr ram_bases[2], ram_sizes[2]; - long bios_size = -1; - target_ulong kernel_base, initrd_base; - long kernel_size, initrd_size; - int linux_boot; - int len; MemoryRegion *sysmem = get_system_memory(); DeviceState *uicdev; @@ -176,7 +253,6 @@ static void ref405ep_init(MachineState *machine) cpu = ppc405ep_init(sysmem, ram_memories, ram_bases, ram_sizes, 33333333, &uicdev, kernel_filename == NULL ? 0 : 1); - env = &cpu->env; /* allocate SRAM */ memory_region_init_ram(sram, NULL, "ef405ep.sram", PPC405EP_SRAM_SIZE, @@ -187,6 +263,7 @@ static void ref405ep_init(MachineState *machine) if (machine->firmware) { MemoryRegion *bios = g_new(MemoryRegion, 1); g_autofree char *filename; + long bios_size; memory_region_init_rom(bios, NULL, "ef405ep.bios", BIOS_SIZE, &error_fatal); @@ -217,54 +294,36 @@ static void ref405ep_init(MachineState *machine) s = SYS_BUS_DEVICE(dev); sysbus_realize_and_unref(s, &error_fatal); sysbus_mmio_map(s, 0, PPC405EP_NVRAM_BASE); - /* Load kernel */ - linux_boot = (kernel_filename != NULL); - if (linux_boot) { - bdloc = ppc405_set_bootinfo(env, machine->ram_size); - env->gpr[3] = bdloc; + + /* Load kernel and initrd using U-Boot images */ + if (kernel_filename && machine->firmware) { + target_ulong kernel_base, initrd_base; + long kernel_size, initrd_size; + kernel_base = KERNEL_LOAD_ADDR; - /* now we can load the kernel */ kernel_size = load_image_targphys(kernel_filename, kernel_base, machine->ram_size - kernel_base); if (kernel_size < 0) { error_report("could not load kernel '%s'", kernel_filename); exit(1); } - printf("Load kernel size %ld at " TARGET_FMT_lx, - kernel_size, kernel_base); + /* load initrd */ - if (initrd_filename) { + if (machine->initrd_filename) { initrd_base = INITRD_LOAD_ADDR; - initrd_size = load_image_targphys(initrd_filename, initrd_base, + initrd_size = load_image_targphys(machine->initrd_filename, + initrd_base, machine->ram_size - initrd_base); if (initrd_size < 0) { error_report("could not load initial ram disk '%s'", - initrd_filename); + machine->initrd_filename); exit(1); } - } else { - initrd_base = 0; - initrd_size = 0; } - env->gpr[4] = initrd_base; - env->gpr[5] = initrd_size; - if (kernel_cmdline != NULL) { - len = strlen(kernel_cmdline); - bdloc -= ((len + 255) & ~255); - cpu_physical_memory_write(bdloc, kernel_cmdline, len + 1); - env->gpr[6] = bdloc; - env->gpr[7] = bdloc + len; - } else { - env->gpr[6] = 0; - env->gpr[7] = 0; - } - env->nip = KERNEL_LOAD_ADDR; - } else { - kernel_base = 0; - kernel_size = 0; - initrd_base = 0; - initrd_size = 0; - bdloc = 0; + + /* Load ELF kernel and rootfs.cpio */ + } else if (kernel_filename && !machine->firmware) { + boot_from_kernel(machine, cpu); } }