arm_init.c   [plain text]


/*
 * Copyright (c) 2007-2009 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 *
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */

#include <debug.h>
#include <mach_ldebug.h>
#include <mach_kdp.h>

#include <kern/misc_protos.h>
#include <kern/thread.h>
#include <kern/timer_queue.h>
#include <kern/processor.h>
#include <kern/startup.h>
#include <kern/debug.h>
#include <prng/random.h>
#include <machine/machine_routines.h>
#include <machine/commpage.h>
/* ARM64_TODO unify boot.h */
#if __arm64__
#include <pexpert/arm64/boot.h>
#elif __arm__
#include <pexpert/arm/boot.h>
#else
#error Unsupported arch
#endif
#include <pexpert/arm/consistent_debug.h>
#include <pexpert/device_tree.h>
#include <arm/proc_reg.h>
#include <arm/pmap.h>
#include <arm/caches_internal.h>
#include <arm/cpu_internal.h>
#include <arm/cpu_data_internal.h>
#include <arm/misc_protos.h>
#include <arm/machine_cpu.h>
#include <arm/rtclock.h>
#include <vm/vm_map.h>

#include <libkern/kernel_mach_header.h>
#include <libkern/stack_protector.h>
#include <libkern/section_keywords.h>
#include <san/kasan.h>

#include <pexpert/pexpert.h>

#include <console/serial_protos.h>

#if CONFIG_TELEMETRY
#include <kern/telemetry.h>
#endif
#if MONOTONIC
#include <kern/monotonic.h>
#endif /* MONOTONIC */

extern void     patch_low_glo(void);
extern int      serial_init(void);
extern void sleep_token_buffer_init(void);

extern vm_offset_t intstack_top;
#if __arm64__
extern vm_offset_t excepstack_top;
#else
extern vm_offset_t fiqstack_top;
#endif

extern const char version[];
extern const char version_variant[];
extern int      disableConsoleOutput;

int             pc_trace_buf[PC_TRACE_BUF_SIZE] = {0};
int             pc_trace_cnt = PC_TRACE_BUF_SIZE;
int             debug_task;

boolean_t up_style_idle_exit = 0;



#if INTERRUPT_MASKED_DEBUG
boolean_t interrupt_masked_debug = 1;
uint64_t interrupt_masked_timeout = 0xd0000;
#endif

boot_args const_boot_args __attribute__((section("__DATA, __const")));
boot_args      *BootArgs __attribute__((section("__DATA, __const")));

unsigned int arm_diag;
#ifdef  APPLETYPHOON
static unsigned cpus_defeatures = 0x0;
extern void cpu_defeatures_set(unsigned int);
#endif

#if __arm64__ && __ARM_GLOBAL_SLEEP_BIT__
extern volatile boolean_t arm64_stall_sleep;
#endif

extern boolean_t force_immediate_debug_halt;

/*
 * Forward definition
 */
void arm_init(boot_args * args);

#if __arm64__
unsigned int page_shift_user32; /* for page_size as seen by a 32-bit task */
#endif /* __arm64__ */


/*
 * JOP rebasing
 */


// Note, the following should come from a header from dyld
static void
rebase_chain(uintptr_t chainStartAddress, uint64_t stepMultiplier, uintptr_t baseAddress __unused, uint64_t slide)
{
	uint64_t delta = 0;
	uintptr_t address = chainStartAddress;
	do {
		uint64_t value = *(uint64_t*)address;

		bool isAuthenticated = (value & (1ULL << 63)) != 0;
		bool isRebase = (value & (1ULL << 62)) == 0;
		if (isRebase) {
			if (isAuthenticated) {
				// The new value for a rebase is the low 32-bits of the threaded value plus the slide.
				uint64_t newValue = (value & 0xFFFFFFFF) + slide;
				// Add in the offset from the mach_header
				newValue += baseAddress;
				*(uint64_t*)address = newValue;
			} else {
				// Regular pointer which needs to fit in 51-bits of value.
				// C++ RTTI uses the top bit, so we'll allow the whole top-byte
				// and the bottom 43-bits to be fit in to 51-bits.
				uint64_t top8Bits = value & 0x0007F80000000000ULL;
				uint64_t bottom43Bits = value & 0x000007FFFFFFFFFFULL;
				uint64_t targetValue = (top8Bits << 13) | (((intptr_t)(bottom43Bits << 21) >> 21) & 0x00FFFFFFFFFFFFFF);
				targetValue = targetValue + slide;
				*(uint64_t*)address = targetValue;
			}
		}

		// The delta is bits [51..61]
		// And bit 62 is to tell us if we are a rebase (0) or bind (1)
		value &= ~(1ULL << 62);
		delta = (value & 0x3FF8000000000000) >> 51;
		address += delta * stepMultiplier;
	} while (delta != 0);
}

// Note, the following method should come from a header from dyld
static bool
rebase_threaded_starts(uint32_t *threadArrayStart, uint32_t *threadArrayEnd,
    uintptr_t macho_header_addr, uintptr_t macho_header_vmaddr, size_t slide)
{
	uint32_t threadStartsHeader = *threadArrayStart;
	uint64_t stepMultiplier = (threadStartsHeader & 1) == 1 ? 8 : 4;
	for (uint32_t* threadOffset = threadArrayStart + 1; threadOffset != threadArrayEnd; ++threadOffset) {
		if (*threadOffset == 0xFFFFFFFF) {
			break;
		}
		rebase_chain(macho_header_addr + *threadOffset, stepMultiplier, macho_header_vmaddr, slide);
	}
	return true;
}

/*
 *		Routine:		arm_init
 *		Function:
 */

extern uint32_t __thread_starts_sect_start[] __asm("section$start$__TEXT$__thread_starts");
extern uint32_t __thread_starts_sect_end[]   __asm("section$end$__TEXT$__thread_starts");

void
arm_init(
	boot_args       *args)
{
	unsigned int    maxmem;
	uint32_t        memsize;
	uint64_t        xmaxmem;
	thread_t        thread;
	processor_t     my_master_proc;

	// rebase and sign jops
	if (&__thread_starts_sect_end[0] != &__thread_starts_sect_start[0]) {
		uintptr_t mh    = (uintptr_t) &_mh_execute_header;
		uintptr_t slide = mh - VM_KERNEL_LINK_ADDRESS;
		rebase_threaded_starts( &__thread_starts_sect_start[0],
		    &__thread_starts_sect_end[0],
		    mh, mh - slide, slide);
	}

	/* If kernel integrity is supported, use a constant copy of the boot args. */
	const_boot_args = *args;
	BootArgs = args = &const_boot_args;

	cpu_data_init(&BootCpuData);

	PE_init_platform(FALSE, args); /* Get platform expert set up */

#if __arm64__


	{
		unsigned int    tmp_16k = 0;

#ifdef  XXXX
		/*
		 * Select the advertised kernel page size; without the boot-arg
		 * we default to the hardware page size for the current platform.
		 */
		if (PE_parse_boot_argn("-vm16k", &tmp_16k, sizeof(tmp_16k))) {
			PAGE_SHIFT_CONST = PAGE_MAX_SHIFT;
		} else {
			PAGE_SHIFT_CONST = ARM_PGSHIFT;
		}
#else
		/*
		 * Select the advertised kernel page size; with the boot-arg
		 * use to the hardware page size for the current platform.
		 */
		int radar_20804515 = 1; /* default: new mode */
		PE_parse_boot_argn("radar_20804515", &radar_20804515, sizeof(radar_20804515));
		if (radar_20804515) {
			if (args->memSize > 1ULL * 1024 * 1024 * 1024) {
				/*
				 * arm64 device with > 1GB of RAM:
				 * kernel uses 16KB pages.
				 */
				PAGE_SHIFT_CONST = PAGE_MAX_SHIFT;
			} else {
				/*
				 * arm64 device with <= 1GB of RAM:
				 * kernel uses hardware page size
				 * (4KB for H6/H7, 16KB for H8+).
				 */
				PAGE_SHIFT_CONST = ARM_PGSHIFT;
			}
			/* 32-bit apps always see 16KB page size */
			page_shift_user32 = PAGE_MAX_SHIFT;
		} else {
			/* kernel page size: */
			if (PE_parse_boot_argn("-use_hwpagesize", &tmp_16k, sizeof(tmp_16k))) {
				PAGE_SHIFT_CONST = ARM_PGSHIFT;
			} else {
				PAGE_SHIFT_CONST = PAGE_MAX_SHIFT;
			}
			/* old mode: 32-bit apps see same page size as kernel */
			page_shift_user32 = PAGE_SHIFT_CONST;
		}
#endif
#ifdef  APPLETYPHOON
		if (PE_parse_boot_argn("cpus_defeatures", &cpus_defeatures, sizeof(cpus_defeatures))) {
			if ((cpus_defeatures & 0xF) != 0) {
				cpu_defeatures_set(cpus_defeatures & 0xF);
			}
		}
#endif
	}
#endif

	ml_parse_cpu_topology();

	master_cpu = ml_get_boot_cpu_number();
	assert(master_cpu >= 0 && master_cpu <= ml_get_max_cpu_number());

	BootCpuData.cpu_number = (unsigned short)master_cpu;
#if     __arm__
	BootCpuData.cpu_exc_vectors = (vm_offset_t)&ExceptionVectorsTable;
#endif
	BootCpuData.intstack_top = (vm_offset_t) &intstack_top;
	BootCpuData.istackptr = BootCpuData.intstack_top;
#if __arm64__
	BootCpuData.excepstack_top = (vm_offset_t) &excepstack_top;
	BootCpuData.excepstackptr = BootCpuData.excepstack_top;
#else
	BootCpuData.fiqstack_top = (vm_offset_t) &fiqstack_top;
	BootCpuData.fiqstackptr = BootCpuData.fiqstack_top;
#endif
	BootCpuData.cpu_processor = cpu_processor_alloc(TRUE);
	BootCpuData.cpu_console_buf = (void *)NULL;
	CpuDataEntries[master_cpu].cpu_data_vaddr = &BootCpuData;
	CpuDataEntries[master_cpu].cpu_data_paddr = (void *)((uintptr_t)(args->physBase)
	    + ((uintptr_t)&BootCpuData
	    - (uintptr_t)(args->virtBase)));

	thread_bootstrap();
	thread = current_thread();
	/*
	 * Preemption is enabled for this thread so that it can lock mutexes without
	 * tripping the preemption check. In reality scheduling is not enabled until
	 * this thread completes, and there are no other threads to switch to, so
	 * preemption level is not really meaningful for the bootstrap thread.
	 */
	thread->machine.preemption_count = 0;
	thread->machine.CpuDatap = &BootCpuData;
#if     __arm__ && __ARM_USER_PROTECT__
	{
		unsigned int ttbr0_val, ttbr1_val, ttbcr_val;
		__asm__ volatile ("mrc p15,0,%0,c2,c0,0\n" : "=r"(ttbr0_val));
		__asm__ volatile ("mrc p15,0,%0,c2,c0,1\n" : "=r"(ttbr1_val));
		__asm__ volatile ("mrc p15,0,%0,c2,c0,2\n" : "=r"(ttbcr_val));
		thread->machine.uptw_ttb = ttbr0_val;
		thread->machine.kptw_ttb = ttbr1_val;
		thread->machine.uptw_ttc = ttbcr_val;
	}
#endif
	BootCpuData.cpu_processor->processor_data.kernel_timer = &thread->system_timer;
	BootCpuData.cpu_processor->processor_data.thread_timer = &thread->system_timer;

	cpu_bootstrap();

	rtclock_early_init();

	kernel_early_bootstrap();

	cpu_init();

	EntropyData.index_ptr = EntropyData.buffer;

	processor_bootstrap();
	my_master_proc = master_processor;

	(void)PE_parse_boot_argn("diag", &arm_diag, sizeof(arm_diag));

	if (PE_parse_boot_argn("maxmem", &maxmem, sizeof(maxmem))) {
		xmaxmem = (uint64_t) maxmem * (1024 * 1024);
	} else if (PE_get_default("hw.memsize", &memsize, sizeof(memsize))) {
		xmaxmem = (uint64_t) memsize;
	} else {
		xmaxmem = 0;
	}

	if (PE_parse_boot_argn("up_style_idle_exit", &up_style_idle_exit, sizeof(up_style_idle_exit))) {
		up_style_idle_exit = 1;
	}
#if INTERRUPT_MASKED_DEBUG
	int wdt_boot_arg = 0;
	/* Disable if WDT is disabled or no_interrupt_mask_debug in boot-args */
	if (PE_parse_boot_argn("no_interrupt_masked_debug", &interrupt_masked_debug,
	    sizeof(interrupt_masked_debug)) || (PE_parse_boot_argn("wdt", &wdt_boot_arg,
	    sizeof(wdt_boot_arg)) && (wdt_boot_arg == -1))) {
		interrupt_masked_debug = 0;
	}

	PE_parse_boot_argn("interrupt_masked_debug_timeout", &interrupt_masked_timeout, sizeof(interrupt_masked_timeout));
#endif



	PE_parse_boot_argn("immediate_NMI", &force_immediate_debug_halt, sizeof(force_immediate_debug_halt));

#if __ARM_PAN_AVAILABLE__
	__builtin_arm_wsr("pan", 1);
#endif  /* __ARM_PAN_AVAILABLE__ */

	arm_vm_init(xmaxmem, args);

	uint32_t debugmode;
	if (PE_parse_boot_argn("debug", &debugmode, sizeof(debugmode)) &&
	    debugmode) {
		patch_low_glo();
	}

	printf_init();
	panic_init();
#if __arm64__
	/* Enable asynchronous exceptions */
	__builtin_arm_wsr("DAIFClr", DAIFSC_ASYNCF);
#endif
#if __arm64__ && WITH_CLASSIC_S2R
	sleep_token_buffer_init();
#endif

	PE_consistent_debug_inherit();

	/* setup debugging output if one has been chosen */
	PE_init_kprintf(FALSE);

	kprintf("kprintf initialized\n");

	serialmode = 0;                                                      /* Assume normal keyboard and console */
	if (PE_parse_boot_argn("serial", &serialmode, sizeof(serialmode))) { /* Do we want a serial
		                                                              * keyboard and/or
		                                                              * console? */
		kprintf("Serial mode specified: %08X\n", serialmode);
		int force_sync = serialmode & SERIALMODE_SYNCDRAIN;
		if (force_sync || PE_parse_boot_argn("drain_uart_sync", &force_sync, sizeof(force_sync))) {
			if (force_sync) {
				serialmode |= SERIALMODE_SYNCDRAIN;
				kprintf(
					"WARNING: Forcing uart driver to output synchronously."
					"printf()s/IOLogs will impact kernel performance.\n"
					"You are advised to avoid using 'drain_uart_sync' boot-arg.\n");
			}
		}
	}
	if (kern_feature_override(KF_SERIAL_OVRD)) {
		serialmode = 0;
	}

	if (serialmode & SERIALMODE_OUTPUT) {                 /* Start serial if requested */
		(void)switch_to_serial_console(); /* Switch into serial mode */
		disableConsoleOutput = FALSE;     /* Allow printfs to happen */
	}
	PE_create_console();

	/* setup console output */
	PE_init_printf(FALSE);

#if __arm64__
#if DEBUG
	dump_kva_space();
#endif
#endif

	cpu_machine_idle_init(TRUE);

#if     (__ARM_ARCH__ == 7)
	if (arm_diag & 0x8000) {
		set_mmu_control((get_mmu_control()) ^ SCTLR_PREDIC);
	}
#endif

	PE_init_platform(TRUE, &BootCpuData);
	cpu_timebase_init(TRUE);
	fiq_context_bootstrap(TRUE);


	/*
	 * Initialize the stack protector for all future calls
	 * to C code. Since kernel_bootstrap() eventually
	 * switches stack context without returning through this
	 * function, we do not risk failing the check even though
	 * we mutate the guard word during execution.
	 */
	__stack_chk_guard = (unsigned long)early_random();
	/* Zero a byte of the protector to guard
	 * against string vulnerabilities
	 */
	__stack_chk_guard &= ~(0xFFULL << 8);
	machine_startup(args);
}

/*
 * Routine:        arm_init_cpu
 * Function:
 *    Re-initialize CPU when coming out of reset
 */

void
arm_init_cpu(
	cpu_data_t      *cpu_data_ptr)
{
#if __ARM_PAN_AVAILABLE__
	__builtin_arm_wsr("pan", 1);
#endif

	cpu_data_ptr->cpu_flags &= ~SleepState;
#if     __ARM_SMP__ && defined(ARMA7)
	cpu_data_ptr->cpu_CLW_active = 1;
#endif

	machine_set_current_thread(cpu_data_ptr->cpu_active_thread);

#if __arm64__
	pmap_clear_user_ttb();
	flush_mmu_tlb();
	/* Enable asynchronous exceptions */
	__builtin_arm_wsr("DAIFClr", DAIFSC_ASYNCF);
#endif

	cpu_machine_idle_init(FALSE);

	cpu_init();

#if     (__ARM_ARCH__ == 7)
	if (arm_diag & 0x8000) {
		set_mmu_control((get_mmu_control()) ^ SCTLR_PREDIC);
	}
#endif
#ifdef  APPLETYPHOON
	if ((cpus_defeatures & (0xF << 4 * cpu_data_ptr->cpu_number)) != 0) {
		cpu_defeatures_set((cpus_defeatures >> 4 * cpu_data_ptr->cpu_number) & 0xF);
	}
#endif
	/* Initialize the timebase before serial_init, as some serial
	 * drivers use mach_absolute_time() to implement rate control
	 */
	cpu_timebase_init(FALSE);

	if (cpu_data_ptr == &BootCpuData) {
#if __arm64__ && __ARM_GLOBAL_SLEEP_BIT__
		/*
		 * Prevent CPUs from going into deep sleep until all
		 * CPUs are ready to do so.
		 */
		arm64_stall_sleep = TRUE;
#endif
		serial_init();
		PE_init_platform(TRUE, NULL);
		commpage_update_timebase();
	}

	fiq_context_init(TRUE);
	cpu_data_ptr->rtcPop = EndOfAllTime;
	timer_resync_deadlines();

#if DEVELOPMENT || DEBUG
	PE_arm_debug_enable_trace();
#endif

	kprintf("arm_cpu_init(): cpu %d online\n", cpu_data_ptr->cpu_processor->cpu_id);

	if (cpu_data_ptr == &BootCpuData) {
#if CONFIG_TELEMETRY
		bootprofile_wake_from_sleep();
#endif /* CONFIG_TELEMETRY */
	}
#if MONOTONIC && defined(__arm64__)
	mt_wake_per_core();
#endif /* MONOTONIC && defined(__arm64__) */


	slave_main(NULL);
}

/*
 * Routine:        arm_init_idle_cpu
 * Function:
 */
void __attribute__((noreturn))
arm_init_idle_cpu(
	cpu_data_t      *cpu_data_ptr)
{
#if __ARM_PAN_AVAILABLE__
	__builtin_arm_wsr("pan", 1);
#endif
#if     __ARM_SMP__ && defined(ARMA7)
	cpu_data_ptr->cpu_CLW_active = 1;
#endif

	machine_set_current_thread(cpu_data_ptr->cpu_active_thread);

#if __arm64__
	pmap_clear_user_ttb();
	flush_mmu_tlb();
	/* Enable asynchronous exceptions */
	__builtin_arm_wsr("DAIFClr", DAIFSC_ASYNCF);
#endif

#if     (__ARM_ARCH__ == 7)
	if (arm_diag & 0x8000) {
		set_mmu_control((get_mmu_control()) ^ SCTLR_PREDIC);
	}
#endif
#ifdef  APPLETYPHOON
	if ((cpus_defeatures & (0xF << 4 * cpu_data_ptr->cpu_number)) != 0) {
		cpu_defeatures_set((cpus_defeatures >> 4 * cpu_data_ptr->cpu_number) & 0xF);
	}
#endif

	fiq_context_init(FALSE);

	cpu_idle_exit(TRUE);
}