[apple/xnu.git] / bsd / dev / arm / kern_machdep.c

/*
 * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
 */
/*
 *	Copyright (C) 1990,  NeXT, Inc.
 *
 *	File:	next/kern_machdep.c
 *	Author:	John Seamons
 *
 *	Machine-specific kernel routines.
 */

#include        <sys/types.h>
#include        <mach/machine.h>
#include        <kern/cpu_number.h>
#include        <machine/exec.h>
#include        <pexpert/arm64/board_config.h>

#if __arm64__
extern int bootarg_no64exec;    /* bsd_init.c */
static cpu_subtype_t cpu_subtype32(void);
#endif /* __arm64__ */

#if __arm64__
/*
 * When an arm64 CPU is executing an arm32 binary, we need to map from the
 * host's 64-bit subtype to the appropriate 32-bit subtype.
 */
static cpu_subtype_t
cpu_subtype32()
{
	switch (cpu_subtype()) {
	case CPU_SUBTYPE_ARM64_V8:
		return CPU_SUBTYPE_ARM_V8;
	default:
		return 0;
	}
}
#endif /* __arm64__*/

/**********************************************************************
* Routine:	grade_binary()
*
* Function:	Return a relative preference for exectypes and
*		execsubtypes in fat executable files.  The higher the
*		grade, the higher the preference.  A grade of 0 means
*		not acceptable.
**********************************************************************/
int
grade_binary(cpu_type_t exectype, cpu_subtype_t execsubtype)
{
#if __arm64__
	cpu_subtype_t hostsubtype =
	    (exectype & CPU_ARCH_ABI64) ? cpu_subtype() : cpu_subtype32();
#else
	cpu_subtype_t hostsubtype = cpu_subtype();
#endif /* __arm64__ */

	switch (exectype) {
#if __arm64__
	case CPU_TYPE_ARM64:
		if (bootarg_no64exec) {
			return 0;
		}

		switch (hostsubtype) {
		case CPU_SUBTYPE_ARM64_V8:
			switch (execsubtype) {
			case CPU_SUBTYPE_ARM64_V8:
				return 10;
			case CPU_SUBTYPE_ARM64_ALL:
				return 9;
			}
			break;

		} /* switch (hostsubtype) */

#else /* __arm64__ */

	case CPU_TYPE_ARM:
		switch (hostsubtype) {
		/*
		 * For 32-bit ARMv8, try the ARMv8 slice before falling back to Swift.
		 */
		case CPU_SUBTYPE_ARM_V8:
			switch (execsubtype) {
			case CPU_SUBTYPE_ARM_V8:
				return 7;
			}
			goto v7s;

			/*
			 * For Swift and later, we prefer to run a swift slice, but fall back
			 * to v7 as Cortex A9 errata should not apply
			 */
v7s:
		case CPU_SUBTYPE_ARM_V7S:
			switch (execsubtype) {
			case CPU_SUBTYPE_ARM_V7S:
				return 6;
			}
			goto v7;

		/*
		 * For Cortex A7, accept v7k only due to differing ABI
		 */
		case CPU_SUBTYPE_ARM_V7K:
			switch (execsubtype) {
			case CPU_SUBTYPE_ARM_V7K:
				return 6;
			}
			break;

		/*
		 * For Cortex A9, we prefer the A9 slice, but will run v7 albeit
		 * under the risk of hitting the NEON load/store errata
		 */
		case CPU_SUBTYPE_ARM_V7F:
			switch (execsubtype) {
			case CPU_SUBTYPE_ARM_V7F:
				return 6;
			}
			goto v7;

v7:
		case CPU_SUBTYPE_ARM_V7:
			switch (execsubtype) {
			case CPU_SUBTYPE_ARM_V7:
				return 5;
			}
		// fall through...

		case CPU_SUBTYPE_ARM_V6:
			switch (execsubtype) {
			case CPU_SUBTYPE_ARM_V6:
				return 4;
			}
		// fall through...

		case CPU_SUBTYPE_ARM_V5TEJ:
			switch (execsubtype) {
			case CPU_SUBTYPE_ARM_V5TEJ:
				return 3;
			}
		// fall through

		case CPU_SUBTYPE_ARM_V4T:
			switch (execsubtype) {
			case CPU_SUBTYPE_ARM_V4T:
				return 2;
			case CPU_SUBTYPE_ARM_ALL:
				return 1;
			}
			break;

		case CPU_SUBTYPE_ARM_XSCALE:
			switch (execsubtype) {
			case CPU_SUBTYPE_ARM_XSCALE:
				return 4;
			case CPU_SUBTYPE_ARM_V5TEJ:
				return 3;
			case CPU_SUBTYPE_ARM_V4T:
				return 2;
			case CPU_SUBTYPE_ARM_ALL:
				return 1;
			}
			break;
		}
#endif /* __arm64__ */
	}

	return 0;
}

boolean_t
pie_required(cpu_type_t exectype, cpu_subtype_t execsubtype)
{
	switch (exectype) {
#if __arm64__
	case CPU_TYPE_ARM64:
		return TRUE;
#endif /* __arm64__ */

	case CPU_TYPE_ARM:
		switch (execsubtype) {
		case CPU_SUBTYPE_ARM_V7K:
			return TRUE;
		}
		break;
	}
	return FALSE;
}
Commit	Line	Data
5ba3f43e A	1	/*
	2	* Copyright (c) 2000-2007 Apple Inc. All rights reserved.
	3	*/
	4	/*
	5	* Copyright (C) 1990, NeXT, Inc.
	6	*
	7	* File: next/kern_machdep.c
	8	* Author: John Seamons
	9	*
	10	* Machine-specific kernel routines.
	11	*/
	12
0a7de745 A	13	#include <sys/types.h>
	14	#include <mach/machine.h>
	15	#include <kern/cpu_number.h>
	16	#include <machine/exec.h>
	17	#include <pexpert/arm64/board_config.h>
5ba3f43e A	18
5ba3f43e A	19	#if __arm64__
0a7de745	20	extern int bootarg_no64exec; /* bsd_init.c */
5ba3f43e A	21	static cpu_subtype_t cpu_subtype32(void);
	22	#endif /* __arm64__ */
	23
	24	#if __arm64__
	25	/*
	26	* When an arm64 CPU is executing an arm32 binary, we need to map from the
	27	* host's 64-bit subtype to the appropriate 32-bit subtype.
	28	*/
	29	static cpu_subtype_t
	30	cpu_subtype32()
	31	{
	32	switch (cpu_subtype()) {
	33	case CPU_SUBTYPE_ARM64_V8:
	34	return CPU_SUBTYPE_ARM_V8;
	35	default:
	36	return 0;
	37	}
	38	}
	39	#endif /* __arm64__*/
	40
	41	/**********************************************************************
0a7de745 A	42	* Routine: grade_binary()
	43	*
	44	* Function: Return a relative preference for exectypes and
	45	* execsubtypes in fat executable files. The higher the
	46	* grade, the higher the preference. A grade of 0 means
	47	* not acceptable.
	48	**********************************************************************/
5ba3f43e A	49	int
	50	grade_binary(cpu_type_t exectype, cpu_subtype_t execsubtype)
	51	{
	52	#if __arm64__
d9a64523	53	cpu_subtype_t hostsubtype =
0a7de745	54	(exectype & CPU_ARCH_ABI64) ? cpu_subtype() : cpu_subtype32();
5ba3f43e A	55	#else
	56	cpu_subtype_t hostsubtype = cpu_subtype();
	57	#endif /* __arm64__ */
	58
	59	switch (exectype) {
	60	#if __arm64__
	61	case CPU_TYPE_ARM64:
0a7de745 A	62	if (bootarg_no64exec) {
	63	return 0;
	64	}
5ba3f43e A	65
	66	switch (hostsubtype) {
	67	case CPU_SUBTYPE_ARM64_V8:
	68	switch (execsubtype) {
	69	case CPU_SUBTYPE_ARM64_V8:
d9a64523	70	return 10;
5ba3f43e	71	case CPU_SUBTYPE_ARM64_ALL:
d9a64523	72	return 9;
5ba3f43e A	73	}
	74	break;
	75
d9a64523	76	} /* switch (hostsubtype) */
5ba3f43e	77
5ba3f43e A	78	#else /* __arm64__ */
	79
	80	case CPU_TYPE_ARM:
	81	switch (hostsubtype) {
	82	/*
	83	* For 32-bit ARMv8, try the ARMv8 slice before falling back to Swift.
	84	*/
	85	case CPU_SUBTYPE_ARM_V8:
	86	switch (execsubtype) {
	87	case CPU_SUBTYPE_ARM_V8:
	88	return 7;
	89	}
	90	goto v7s;
	91
0a7de745 A	92	/*
	93	* For Swift and later, we prefer to run a swift slice, but fall back
	94	* to v7 as Cortex A9 errata should not apply
	95	*/
5ba3f43e A	96	v7s:
	97	case CPU_SUBTYPE_ARM_V7S:
	98	switch (execsubtype) {
	99	case CPU_SUBTYPE_ARM_V7S:
	100	return 6;
	101	}
	102	goto v7;
	103
	104	/*
	105	* For Cortex A7, accept v7k only due to differing ABI
	106	*/
	107	case CPU_SUBTYPE_ARM_V7K:
	108	switch (execsubtype) {
	109	case CPU_SUBTYPE_ARM_V7K:
	110	return 6;
	111	}
0a7de745	112	break;
5ba3f43e A	113
	114	/*
	115	* For Cortex A9, we prefer the A9 slice, but will run v7 albeit
	116	* under the risk of hitting the NEON load/store errata
	117	*/
	118	case CPU_SUBTYPE_ARM_V7F:
	119	switch (execsubtype) {
	120	case CPU_SUBTYPE_ARM_V7F:
	121	return 6;
	122	}
	123	goto v7;
	124
	125	v7:
	126	case CPU_SUBTYPE_ARM_V7:
	127	switch (execsubtype) {
	128	case CPU_SUBTYPE_ARM_V7:
	129	return 5;
	130	}
0a7de745	131	// fall through...
5ba3f43e A	132
	133	case CPU_SUBTYPE_ARM_V6:
	134	switch (execsubtype) {
	135	case CPU_SUBTYPE_ARM_V6:
	136	return 4;
	137	}
0a7de745	138	// fall through...
5ba3f43e A	139
	140	case CPU_SUBTYPE_ARM_V5TEJ:
	141	switch (execsubtype) {
	142	case CPU_SUBTYPE_ARM_V5TEJ:
	143	return 3;
	144	}
0a7de745	145	// fall through
5ba3f43e A	146
	147	case CPU_SUBTYPE_ARM_V4T:
	148	switch (execsubtype) {
	149	case CPU_SUBTYPE_ARM_V4T:
	150	return 2;
	151	case CPU_SUBTYPE_ARM_ALL:
	152	return 1;
	153	}
	154	break;
	155
	156	case CPU_SUBTYPE_ARM_XSCALE:
	157	switch (execsubtype) {
	158	case CPU_SUBTYPE_ARM_XSCALE:
	159	return 4;
	160	case CPU_SUBTYPE_ARM_V5TEJ:
	161	return 3;
	162	case CPU_SUBTYPE_ARM_V4T:
	163	return 2;
	164	case CPU_SUBTYPE_ARM_ALL:
	165	return 1;
	166	}
	167	break;
	168	}
	169	#endif /* __arm64__ */
	170	}
	171
	172	return 0;
	173	}
	174
	175	boolean_t
	176	pie_required(cpu_type_t exectype, cpu_subtype_t execsubtype)
	177	{
	178	switch (exectype) {
	179	#if __arm64__
	180	case CPU_TYPE_ARM64:
	181	return TRUE;
	182	#endif /* __arm64__ */
	183
	184	case CPU_TYPE_ARM:
	185	switch (execsubtype) {
0a7de745 A	186	case CPU_SUBTYPE_ARM_V7K:
	187	return TRUE;
	188	}
5ba3f43e A	189	break;
	190	}
	191	return FALSE;
	192	}