Halt/reboot support for Linux, by Daniel Jacobowitz. This is a band-aid (6ae81775) · Commits · SUMMER2020 / students / proj-2021291

hw/mips_r4k.c

+100 −33

Original line number	Diff line number	Diff line
		@@ -110,6 +110,93 @@ void cpu_mips_clock_init (CPUState *env)
		cpu_mips_update_count(env, 1, 0);
		}

		static void mips_qemu_writel (void *opaque, target_phys_addr_t addr,
		uint32_t val)
		{
		if ((addr & 0xffff) == 0 && val == 42)
		qemu_system_reset_request ();
		else if ((addr & 0xffff) == 4 && val == 42)
		qemu_system_shutdown_request ();
		}

		static uint32_t mips_qemu_readl (void *opaque, target_phys_addr_t addr)
		{
		return 0;
		}

		static CPUWriteMemoryFunc *mips_qemu_write[] = {
		&mips_qemu_writel,
		&mips_qemu_writel,
		&mips_qemu_writel,
		};

		static CPUReadMemoryFunc *mips_qemu_read[] = {
		&mips_qemu_readl,
		&mips_qemu_readl,
		&mips_qemu_readl,
		};

		static int mips_qemu_iomemtype = 0;

		void load_kernel (CPUState env, int ram_size, const char kernel_filename,
		const char *kernel_cmdline,
		const char *initrd_filename)
		{
		int64_t entry = 0;
		long kernel_size, initrd_size;

		kernel_size = load_elf(kernel_filename, VIRT_TO_PHYS_ADDEND, &entry);
		if (kernel_size >= 0)
		env->PC = entry;
		else {
		kernel_size = load_image(kernel_filename,
		phys_ram_base + KERNEL_LOAD_ADDR + VIRT_TO_PHYS_ADDEND);
		if (kernel_size < 0) {
		fprintf(stderr, "qemu: could not load kernel '%s'\n",
		kernel_filename);
		exit(1);
		}
		env->PC = KERNEL_LOAD_ADDR;
		}

		/* load initrd */
		initrd_size = 0;
		if (initrd_filename) {
		initrd_size = load_image(initrd_filename,
		phys_ram_base + INITRD_LOAD_ADDR + VIRT_TO_PHYS_ADDEND);
		if (initrd_size == (target_ulong) -1) {
		fprintf(stderr, "qemu: could not load initial ram disk '%s'\n",
		initrd_filename);
		exit(1);
		}
		}

		/* Store command line. */
		if (initrd_size > 0) {
		int ret;
		ret = sprintf(phys_ram_base + (16 << 20) - 256,
		"rd_start=0x%08x rd_size=%li ",
		INITRD_LOAD_ADDR,
		initrd_size);
		strcpy (phys_ram_base + (16 << 20) - 256 + ret, kernel_cmdline);
		}
		else {
		strcpy (phys_ram_base + (16 << 20) - 256, kernel_cmdline);
		}

		(int )(phys_ram_base + (16 << 20) - 260) = tswap32 (0x12345678);
		(int )(phys_ram_base + (16 << 20) - 264) = tswap32 (ram_size);
		}

		static void main_cpu_reset(void *opaque)
		{
		CPUState *env = opaque;
		cpu_reset(env);

		if (env->kernel_filename)
		load_kernel (env, env->ram_size, env->kernel_filename,
		env->kernel_cmdline, env->initrd_filename);
		}

		void mips_r4k_init (int ram_size, int vga_ram_size, int boot_device,
		DisplayState ds, const char *fd_filename, int snapshot,
		@@ -117,19 +204,24 @@ void mips_r4k_init (int ram_size, int vga_ram_size, int boot_device,
		const char *initrd_filename)
		{
		char buf[1024];
		int64_t entry = 0;
		unsigned long bios_offset;
		int ret;
		CPUState *env;
		long kernel_size;
		int i;

		env = cpu_init();
		register_savevm("cpu", 0, 3, cpu_save, cpu_load, env);
		qemu_register_reset(main_cpu_reset, env);

		/* allocate RAM */
		cpu_register_physical_memory(0, ram_size, IO_MEM_RAM);

		if (!mips_qemu_iomemtype) {
		mips_qemu_iomemtype = cpu_register_io_memory(0, mips_qemu_read,
		mips_qemu_write, NULL);
		}
		cpu_register_physical_memory(0x1fbf0000, 0x10000, mips_qemu_iomemtype);

		/* Try to load a BIOS image. If this fails, we continue regardless,
		but initialize the hardware ourselves. When a kernel gets
		preloaded we also initialize the hardware, since the BIOS wasn't
		@@ -146,38 +238,13 @@ void mips_r4k_init (int ram_size, int vga_ram_size, int boot_device,
		buf);
		}

		kernel_size = 0;
		if (kernel_filename) {
		kernel_size = load_elf(kernel_filename, VIRT_TO_PHYS_ADDEND, &entry);
		if (kernel_size >= 0)
		env->PC = entry;
		else {
		kernel_size = load_image(kernel_filename,
		phys_ram_base + KERNEL_LOAD_ADDR + VIRT_TO_PHYS_ADDEND);
		if (kernel_size < 0) {
		fprintf(stderr, "qemu: could not load kernel '%s'\n",
		kernel_filename);
		exit(1);
		}
		env->PC = KERNEL_LOAD_ADDR;
		}

		/* load initrd */
		if (initrd_filename) {
		if (load_image(initrd_filename,
		phys_ram_base + INITRD_LOAD_ADDR + VIRT_TO_PHYS_ADDEND)
		== (target_ulong) -1) {
		fprintf(stderr, "qemu: could not load initial ram disk '%s'\n",
		load_kernel (env, ram_size, kernel_filename, kernel_cmdline,
		initrd_filename);
		exit(1);
		}
		}

		/* Store command line. */
		strcpy (phys_ram_base + (16 << 20) - 256, kernel_cmdline);
		/* FIXME: little endian support */
		(int )(phys_ram_base + (16 << 20) - 260) = tswap32 (0x12345678);
		(int )(phys_ram_base + (16 << 20) - 264) = tswap32 (ram_size);
		env->ram_size = ram_size;
		env->kernel_filename = kernel_filename;
		env->kernel_cmdline = kernel_cmdline;
		env->initrd_filename = initrd_filename;
		}

		/* Init internal devices */

target-mips/cpu.h

+7 −1

Original line number	Diff line number	Diff line
		@@ -182,7 +182,6 @@ struct CPUMIPSState {
		uint32_t CP0_ErrorEPC;
		uint32_t CP0_DESAVE;
		/* Qemu */
		struct QEMUTimer timer; / Internal timer */
		int interrupt_request;
		jmp_buf jmp_env;
		int exception_index;
		@@ -213,6 +212,13 @@ struct CPUMIPSState {
		int halted; /* TRUE if the CPU is in suspend state */

		CPU_COMMON

		int ram_size;
		const char *kernel_filename;
		const char *kernel_cmdline;
		const char *initrd_filename;

		struct QEMUTimer timer; / Internal timer */
		};

		#include "cpu-all.h"

target-mips/translate.c

+9 −1

Original line number	Diff line number	Diff line
		@@ -2425,7 +2425,16 @@ CPUMIPSState *cpu_mips_init (void)
		if (!env)
		return NULL;
		cpu_exec_init(env);
		cpu_reset(env);
		return env;
		}

		void cpu_reset (CPUMIPSState *env)
		{
		memset(env, 0, offsetof(CPUMIPSState, breakpoints));

		tlb_flush(env, 1);

		/* Minimal init */
		env->PC = 0xBFC00000;
		#if defined (MIPS_USES_R4K_TLB)
		@@ -2456,5 +2465,4 @@ CPUMIPSState *cpu_mips_init (void)
		#ifdef MIPS_USES_FPU
		env->fcr0 = MIPS_FCR0;
		#endif
		return env;
		}