[deliverable/linux.git] / arch / powerpc / lib / feature-fixups.c

/*
 *  Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org)
 *
 *  Modifications for ppc64:
 *      Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com>
 *
 *  Copyright 2008 Michael Ellerman, IBM Corporation.
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version
 *  2 of the License, or (at your option) any later version.
 */

#include <linux/types.h>
#include <linux/jump_label.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/init.h>
#include <asm/cputable.h>
#include <asm/code-patching.h>
#include <asm/page.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/firmware.h>

struct fixup_entry {
	unsigned long	mask;
	unsigned long	value;
	long		start_off;
	long		end_off;
	long		alt_start_off;
	long		alt_end_off;
};

static unsigned int *calc_addr(struct fixup_entry *fcur, long offset)
{
	/*
	 * We store the offset to the code as a negative offset from
	 * the start of the alt_entry, to support the VDSO. This
	 * routine converts that back into an actual address.
	 */
	return (unsigned int *)((unsigned long)fcur + offset);
}

static int patch_alt_instruction(unsigned int *src, unsigned int *dest,
				 unsigned int *alt_start, unsigned int *alt_end)
{
	unsigned int instr;

	instr = *src;

	if (instr_is_relative_branch(*src)) {
		unsigned int *target = (unsigned int *)branch_target(src);

		/* Branch within the section doesn't need translating */
		if (target < alt_start || target >= alt_end) {
			instr = translate_branch(dest, src);
			if (!instr)
				return 1;
		}
	}

	patch_instruction(dest, instr);

	return 0;
}

static int patch_feature_section(unsigned long value, struct fixup_entry *fcur)
{
	unsigned int *start, *end, *alt_start, *alt_end, *src, *dest;

	start = calc_addr(fcur, fcur->start_off);
	end = calc_addr(fcur, fcur->end_off);
	alt_start = calc_addr(fcur, fcur->alt_start_off);
	alt_end = calc_addr(fcur, fcur->alt_end_off);

	if ((alt_end - alt_start) > (end - start))
		return 1;

	if ((value & fcur->mask) == fcur->value)
		return 0;

	src = alt_start;
	dest = start;

	for (; src < alt_end; src++, dest++) {
		if (patch_alt_instruction(src, dest, alt_start, alt_end))
			return 1;
	}

	for (; dest < end; dest++)
		patch_instruction(dest, PPC_INST_NOP);

	return 0;
}

void do_feature_fixups(unsigned long value, void *fixup_start, void *fixup_end)
{
	struct fixup_entry *fcur, *fend;

	fcur = fixup_start;
	fend = fixup_end;

	for (; fcur < fend; fcur++) {
		if (patch_feature_section(value, fcur)) {
			WARN_ON(1);
			printk("Unable to patch feature section at %p - %p" \
				" with %p - %p\n",
				calc_addr(fcur, fcur->start_off),
				calc_addr(fcur, fcur->end_off),
				calc_addr(fcur, fcur->alt_start_off),
				calc_addr(fcur, fcur->alt_end_off));
		}
	}
}

void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end)
{
	long *start, *end;
	unsigned int *dest;

	if (!(value & CPU_FTR_LWSYNC))
		return ;

	start = fixup_start;
	end = fixup_end;

	for (; start < end; start++) {
		dest = (void *)start + *start;
		patch_instruction(dest, PPC_INST_LWSYNC);
	}
}

static void do_final_fixups(void)
{
#if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE)
	int *src, *dest;
	unsigned long length;

	if (PHYSICAL_START == 0)
		return;

	src = (int *)(KERNELBASE + PHYSICAL_START);
	dest = (int *)KERNELBASE;
	length = (__end_interrupts - _stext) / sizeof(int);

	while (length--) {
		patch_instruction(dest, *src);
		src++;
		dest++;
	}
#endif
}

static unsigned long __initdata saved_cpu_features;
static unsigned int __initdata saved_mmu_features;
#ifdef CONFIG_PPC64
static unsigned long __initdata saved_firmware_features;
#endif

void __init apply_feature_fixups(void)
{
	struct cpu_spec *spec = PTRRELOC(*PTRRELOC(&cur_cpu_spec));

	*PTRRELOC(&saved_cpu_features) = spec->cpu_features;
	*PTRRELOC(&saved_mmu_features) = spec->mmu_features;

	/*
	 * Apply the CPU-specific and firmware specific fixups to kernel text
	 * (nop out sections not relevant to this CPU or this firmware).
	 */
	do_feature_fixups(spec->cpu_features,
			  PTRRELOC(&__start___ftr_fixup),
			  PTRRELOC(&__stop___ftr_fixup));

	do_feature_fixups(spec->mmu_features,
			  PTRRELOC(&__start___mmu_ftr_fixup),
			  PTRRELOC(&__stop___mmu_ftr_fixup));

	do_lwsync_fixups(spec->cpu_features,
			 PTRRELOC(&__start___lwsync_fixup),
			 PTRRELOC(&__stop___lwsync_fixup));

#ifdef CONFIG_PPC64
	saved_firmware_features = powerpc_firmware_features;
	do_feature_fixups(powerpc_firmware_features,
			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
#endif
	do_final_fixups();
}

void __init setup_feature_keys(void)
{
	/*
	 * Initialise jump label. This causes all the cpu/mmu_has_feature()
	 * checks to take on their correct polarity based on the current set of
	 * CPU/MMU features.
	 */
	jump_label_init();
	cpu_feature_keys_init();
	mmu_feature_keys_init();
}

static int __init check_features(void)
{
	WARN(saved_cpu_features != cur_cpu_spec->cpu_features,
	     "CPU features changed after feature patching!\n");
	WARN(saved_mmu_features != cur_cpu_spec->mmu_features,
	     "MMU features changed after feature patching!\n");
#ifdef CONFIG_PPC64
	WARN(saved_firmware_features != powerpc_firmware_features,
	     "Firmware features changed after feature patching!\n");
#endif

	return 0;
}
late_initcall(check_features);

#ifdef CONFIG_FTR_FIXUP_SELFTEST

#define check(x)	\
	if (!(x)) printk("feature-fixups: test failed at line %d\n", __LINE__);

/* This must be after the text it fixes up, vmlinux.lds.S enforces that atm */
static struct fixup_entry fixup;

static long calc_offset(struct fixup_entry *entry, unsigned int *p)
{
	return (unsigned long)p - (unsigned long)entry;
}

static void test_basic_patching(void)
{
	extern unsigned int ftr_fixup_test1;
	extern unsigned int end_ftr_fixup_test1;
	extern unsigned int ftr_fixup_test1_orig;
	extern unsigned int ftr_fixup_test1_expected;
	int size = &end_ftr_fixup_test1 - &ftr_fixup_test1;

	fixup.value = fixup.mask = 8;
	fixup.start_off = calc_offset(&fixup, &ftr_fixup_test1 + 1);
	fixup.end_off = calc_offset(&fixup, &ftr_fixup_test1 + 2);
	fixup.alt_start_off = fixup.alt_end_off = 0;

	/* Sanity check */
	check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_orig, size) == 0);

	/* Check we don't patch if the value matches */
	patch_feature_section(8, &fixup);
	check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_orig, size) == 0);

	/* Check we do patch if the value doesn't match */
	patch_feature_section(0, &fixup);
	check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_expected, size) == 0);

	/* Check we do patch if the mask doesn't match */
	memcpy(&ftr_fixup_test1, &ftr_fixup_test1_orig, size);
	check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_orig, size) == 0);
	patch_feature_section(~8, &fixup);
	check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_expected, size) == 0);
}

static void test_alternative_patching(void)
{
	extern unsigned int ftr_fixup_test2;
	extern unsigned int end_ftr_fixup_test2;
	extern unsigned int ftr_fixup_test2_orig;
	extern unsigned int ftr_fixup_test2_alt;
	extern unsigned int ftr_fixup_test2_expected;
	int size = &end_ftr_fixup_test2 - &ftr_fixup_test2;

	fixup.value = fixup.mask = 0xF;
	fixup.start_off = calc_offset(&fixup, &ftr_fixup_test2 + 1);
	fixup.end_off = calc_offset(&fixup, &ftr_fixup_test2 + 2);
	fixup.alt_start_off = calc_offset(&fixup, &ftr_fixup_test2_alt);
	fixup.alt_end_off = calc_offset(&fixup, &ftr_fixup_test2_alt + 1);

	/* Sanity check */
	check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_orig, size) == 0);

	/* Check we don't patch if the value matches */
	patch_feature_section(0xF, &fixup);
	check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_orig, size) == 0);

	/* Check we do patch if the value doesn't match */
	patch_feature_section(0, &fixup);
	check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_expected, size) == 0);

	/* Check we do patch if the mask doesn't match */
	memcpy(&ftr_fixup_test2, &ftr_fixup_test2_orig, size);
	check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_orig, size) == 0);
	patch_feature_section(~0xF, &fixup);
	check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_expected, size) == 0);
}

static void test_alternative_case_too_big(void)
{
	extern unsigned int ftr_fixup_test3;
	extern unsigned int end_ftr_fixup_test3;
	extern unsigned int ftr_fixup_test3_orig;
	extern unsigned int ftr_fixup_test3_alt;
	int size = &end_ftr_fixup_test3 - &ftr_fixup_test3;

	fixup.value = fixup.mask = 0xC;
	fixup.start_off = calc_offset(&fixup, &ftr_fixup_test3 + 1);
	fixup.end_off = calc_offset(&fixup, &ftr_fixup_test3 + 2);
	fixup.alt_start_off = calc_offset(&fixup, &ftr_fixup_test3_alt);
	fixup.alt_end_off = calc_offset(&fixup, &ftr_fixup_test3_alt + 2);

	/* Sanity check */
	check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0);

	/* Expect nothing to be patched, and the error returned to us */
	check(patch_feature_section(0xF, &fixup) == 1);
	check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0);
	check(patch_feature_section(0, &fixup) == 1);
	check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0);
	check(patch_feature_section(~0xF, &fixup) == 1);
	check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0);
}

static void test_alternative_case_too_small(void)
{
	extern unsigned int ftr_fixup_test4;
	extern unsigned int end_ftr_fixup_test4;
	extern unsigned int ftr_fixup_test4_orig;
	extern unsigned int ftr_fixup_test4_alt;
	extern unsigned int ftr_fixup_test4_expected;
	int size = &end_ftr_fixup_test4 - &ftr_fixup_test4;
	unsigned long flag;

	/* Check a high-bit flag */
	flag = 1UL << ((sizeof(unsigned long) - 1) * 8);
	fixup.value = fixup.mask = flag;
	fixup.start_off = calc_offset(&fixup, &ftr_fixup_test4 + 1);
	fixup.end_off = calc_offset(&fixup, &ftr_fixup_test4 + 5);
	fixup.alt_start_off = calc_offset(&fixup, &ftr_fixup_test4_alt);
	fixup.alt_end_off = calc_offset(&fixup, &ftr_fixup_test4_alt + 2);

	/* Sanity check */
	check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_orig, size) == 0);

	/* Check we don't patch if the value matches */
	patch_feature_section(flag, &fixup);
	check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_orig, size) == 0);

	/* Check we do patch if the value doesn't match */
	patch_feature_section(0, &fixup);
	check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_expected, size) == 0);

	/* Check we do patch if the mask doesn't match */
	memcpy(&ftr_fixup_test4, &ftr_fixup_test4_orig, size);
	check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_orig, size) == 0);
	patch_feature_section(~flag, &fixup);
	check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_expected, size) == 0);
}

static void test_alternative_case_with_branch(void)
{
	extern unsigned int ftr_fixup_test5;
	extern unsigned int end_ftr_fixup_test5;
	extern unsigned int ftr_fixup_test5_expected;
	int size = &end_ftr_fixup_test5 - &ftr_fixup_test5;

	check(memcmp(&ftr_fixup_test5, &ftr_fixup_test5_expected, size) == 0);
}

static void test_alternative_case_with_external_branch(void)
{
	extern unsigned int ftr_fixup_test6;
	extern unsigned int end_ftr_fixup_test6;
	extern unsigned int ftr_fixup_test6_expected;
	int size = &end_ftr_fixup_test6 - &ftr_fixup_test6;

	check(memcmp(&ftr_fixup_test6, &ftr_fixup_test6_expected, size) == 0);
}

static void test_cpu_macros(void)
{
	extern u8 ftr_fixup_test_FTR_macros;
	extern u8 ftr_fixup_test_FTR_macros_expected;
	unsigned long size = &ftr_fixup_test_FTR_macros_expected -
			     &ftr_fixup_test_FTR_macros;

	/* The fixups have already been done for us during boot */
	check(memcmp(&ftr_fixup_test_FTR_macros,
		     &ftr_fixup_test_FTR_macros_expected, size) == 0);
}

static void test_fw_macros(void)
{
#ifdef CONFIG_PPC64
	extern u8 ftr_fixup_test_FW_FTR_macros;
	extern u8 ftr_fixup_test_FW_FTR_macros_expected;
	unsigned long size = &ftr_fixup_test_FW_FTR_macros_expected -
			     &ftr_fixup_test_FW_FTR_macros;

	/* The fixups have already been done for us during boot */
	check(memcmp(&ftr_fixup_test_FW_FTR_macros,
		     &ftr_fixup_test_FW_FTR_macros_expected, size) == 0);
#endif
}

static void test_lwsync_macros(void)
{
	extern u8 lwsync_fixup_test;
	extern u8 end_lwsync_fixup_test;
	extern u8 lwsync_fixup_test_expected_LWSYNC;
	extern u8 lwsync_fixup_test_expected_SYNC;
	unsigned long size = &end_lwsync_fixup_test -
			     &lwsync_fixup_test;

	/* The fixups have already been done for us during boot */
	if (cur_cpu_spec->cpu_features & CPU_FTR_LWSYNC) {
		check(memcmp(&lwsync_fixup_test,
			     &lwsync_fixup_test_expected_LWSYNC, size) == 0);
	} else {
		check(memcmp(&lwsync_fixup_test,
			     &lwsync_fixup_test_expected_SYNC, size) == 0);
	}
}

static int __init test_feature_fixups(void)
{
	printk(KERN_DEBUG "Running feature fixup self-tests ...\n");

	test_basic_patching();
	test_alternative_patching();
	test_alternative_case_too_big();
	test_alternative_case_too_small();
	test_alternative_case_with_branch();
	test_alternative_case_with_external_branch();
	test_cpu_macros();
	test_fw_macros();
	test_lwsync_macros();

	return 0;
}
late_initcall(test_feature_fixups);

#endif /* CONFIG_FTR_FIXUP_SELFTEST */
Commit	Line	Data
51c52e86 ME	1	/*
	2	* Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org)
	3	*
	4	* Modifications for ppc64:
	5	* Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com>
	6	*
	7	* Copyright 2008 Michael Ellerman, IBM Corporation.
	8	*
	9	* This program is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU General Public License
	11	* as published by the Free Software Foundation; either version
	12	* 2 of the License, or (at your option) any later version.
	13	*/
	14
3880ecb0	15	#include <linux/types.h>
309b315b	16	#include <linux/jump_label.h>
51c52e86	17	#include <linux/kernel.h>
362e7701 ME	18	#include <linux/string.h>
362e7701 ME	19	#include <linux/init.h>
51c52e86 ME	20	#include <asm/cputable.h>
51c52e86 ME	21	#include <asm/code-patching.h>
d715e433 AB	22	#include <asm/page.h>
d715e433 AB	23	#include <asm/sections.h>
9402c684 BH	24	#include <asm/setup.h>
9402c684 BH	25	#include <asm/firmware.h>
51c52e86 ME	26
	27	struct fixup_entry {
	28	unsigned long mask;
	29	unsigned long value;
	30	long start_off;
	31	long end_off;
fac23fe4 ME	32	long alt_start_off;
fac23fe4 ME	33	long alt_end_off;
51c52e86 ME	34	};
51c52e86 ME	35
9b1a735d	36	static unsigned int calc_addr(struct fixup_entry fcur, long offset)
51c52e86	37	{
9b1a735d ME	38	/*
	39	* We store the offset to the code as a negative offset from
	40	* the start of the alt_entry, to support the VDSO. This
	41	* routine converts that back into an actual address.
	42	*/
	43	return (unsigned int *)((unsigned long)fcur + offset);
	44	}
	45
	46	static int patch_alt_instruction(unsigned int src, unsigned int dest,
	47	unsigned int alt_start, unsigned int alt_end)
	48	{
	49	unsigned int instr;
	50
	51	instr = *src;
	52
	53	if (instr_is_relative_branch(*src)) {
	54	unsigned int target = (unsigned int )branch_target(src);
	55
	56	/* Branch within the section doesn't need translating */
	57	if (target < alt_start \|\| target >= alt_end) {
	58	instr = translate_branch(dest, src);
	59	if (!instr)
	60	return 1;
	61	}
	62	}
	63
	64	patch_instruction(dest, instr);
	65
	66	return 0;
	67	}
	68
	69	static int patch_feature_section(unsigned long value, struct fixup_entry *fcur)
	70	{
	71	unsigned int start, end, alt_start, alt_end, src, dest;
	72
	73	start = calc_addr(fcur, fcur->start_off);
	74	end = calc_addr(fcur, fcur->end_off);
	75	alt_start = calc_addr(fcur, fcur->alt_start_off);
	76	alt_end = calc_addr(fcur, fcur->alt_end_off);
	77
	78	if ((alt_end - alt_start) > (end - start))
	79	return 1;
51c52e86 ME	80
51c52e86 ME	81	if ((value & fcur->mask) == fcur->value)
9b1a735d	82	return 0;
51c52e86	83
9b1a735d ME	84	src = alt_start;
9b1a735d ME	85	dest = start;
51c52e86	86
9b1a735d ME	87	for (; src < alt_end; src++, dest++) {
	88	if (patch_alt_instruction(src, dest, alt_start, alt_end))
	89	return 1;
51c52e86	90	}
9b1a735d ME	91
9b1a735d ME	92	for (; dest < end; dest++)
16c57b36	93	patch_instruction(dest, PPC_INST_NOP);
9b1a735d ME	94
9b1a735d ME	95	return 0;
51c52e86 ME	96	}
	97
	98	void do_feature_fixups(unsigned long value, void fixup_start, void fixup_end)
	99	{
	100	struct fixup_entry fcur, fend;
	101
	102	fcur = fixup_start;
	103	fend = fixup_end;
	104
9b1a735d ME	105	for (; fcur < fend; fcur++) {
9b1a735d ME	106	if (patch_feature_section(value, fcur)) {
1856c020	107	WARN_ON(1);
9b1a735d ME	108	printk("Unable to patch feature section at %p - %p" \
	109	" with %p - %p\n",
	110	calc_addr(fcur, fcur->start_off),
	111	calc_addr(fcur, fcur->end_off),
	112	calc_addr(fcur, fcur->alt_start_off),
	113	calc_addr(fcur, fcur->alt_end_off));
	114	}
	115	}
51c52e86	116	}
362e7701	117
2d1b2027 KG	118	void do_lwsync_fixups(unsigned long value, void fixup_start, void fixup_end)
2d1b2027 KG	119	{
3d98ffbf BH	120	long start, end;
3d98ffbf BH	121	unsigned int *dest;
2d1b2027 KG	122
	123	if (!(value & CPU_FTR_LWSYNC))
	124	return ;
	125
	126	start = fixup_start;
	127	end = fixup_end;
	128
	129	for (; start < end; start++) {
	130	dest = (void )start + start;
16c57b36	131	patch_instruction(dest, PPC_INST_LWSYNC);
2d1b2027 KG	132	}
	133	}
	134
9402c684	135	static void do_final_fixups(void)
d715e433 AB	136	{
	137	#if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE)
	138	int src, dest;
	139	unsigned long length;
	140
	141	if (PHYSICAL_START == 0)
	142	return;
	143
	144	src = (int *)(KERNELBASE + PHYSICAL_START);
	145	dest = (int *)KERNELBASE;
	146	length = (__end_interrupts - _stext) / sizeof(int);
	147
	148	while (length--) {
	149	patch_instruction(dest, *src);
	150	src++;
	151	dest++;
	152	}
	153	#endif
	154	}
	155
a28e46f1 ME	156	static unsigned long __initdata saved_cpu_features;
	157	static unsigned int __initdata saved_mmu_features;
	158	#ifdef CONFIG_PPC64
	159	static unsigned long __initdata saved_firmware_features;
	160	#endif
	161
	162	void __init apply_feature_fixups(void)
9402c684	163	{
2c0f9951	164	struct cpu_spec spec = PTRRELOC(PTRRELOC(&cur_cpu_spec));
9402c684	165
a28e46f1 ME	166	*PTRRELOC(&saved_cpu_features) = spec->cpu_features;
	167	*PTRRELOC(&saved_mmu_features) = spec->mmu_features;
	168
9402c684 BH	169	/*
	170	* Apply the CPU-specific and firmware specific fixups to kernel text
	171	* (nop out sections not relevant to this CPU or this firmware).
	172	*/
	173	do_feature_fixups(spec->cpu_features,
	174	PTRRELOC(&__start___ftr_fixup),
	175	PTRRELOC(&__stop___ftr_fixup));
	176
	177	do_feature_fixups(spec->mmu_features,
	178	PTRRELOC(&__start___mmu_ftr_fixup),
	179	PTRRELOC(&__stop___mmu_ftr_fixup));
	180
	181	do_lwsync_fixups(spec->cpu_features,
	182	PTRRELOC(&__start___lwsync_fixup),
	183	PTRRELOC(&__stop___lwsync_fixup));
	184
	185	#ifdef CONFIG_PPC64
a28e46f1	186	saved_firmware_features = powerpc_firmware_features;
9402c684 BH	187	do_feature_fixups(powerpc_firmware_features,
	188	&__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
	189	#endif
	190	do_final_fixups();
97f6e0cc	191	}
309b315b	192
97f6e0cc BH	193	void __init setup_feature_keys(void)
97f6e0cc BH	194	{
309b315b AK	195	/*
	196	* Initialise jump label. This causes all the cpu/mmu_has_feature()
	197	* checks to take on their correct polarity based on the current set of
	198	* CPU/MMU features.
	199	*/
	200	jump_label_init();
4db73271	201	cpu_feature_keys_init();
c12e6f24	202	mmu_feature_keys_init();
9402c684 BH	203	}
9402c684 BH	204
a28e46f1 ME	205	static int __init check_features(void)
	206	{
	207	WARN(saved_cpu_features != cur_cpu_spec->cpu_features,
	208	"CPU features changed after feature patching!\n");
	209	WARN(saved_mmu_features != cur_cpu_spec->mmu_features,
	210	"MMU features changed after feature patching!\n");
	211	#ifdef CONFIG_PPC64
	212	WARN(saved_firmware_features != powerpc_firmware_features,
	213	"Firmware features changed after feature patching!\n");
	214	#endif
	215
	216	return 0;
	217	}
	218	late_initcall(check_features);
	219
362e7701 ME	220	#ifdef CONFIG_FTR_FIXUP_SELFTEST
	221
	222	#define check(x) \
	223	if (!(x)) printk("feature-fixups: test failed at line %d\n", __LINE__);
	224
	225	/* This must be after the text it fixes up, vmlinux.lds.S enforces that atm */
	226	static struct fixup_entry fixup;
	227
	228	static long calc_offset(struct fixup_entry entry, unsigned int p)
	229	{
	230	return (unsigned long)p - (unsigned long)entry;
	231	}
	232
e51df2c1	233	static void test_basic_patching(void)
362e7701 ME	234	{
	235	extern unsigned int ftr_fixup_test1;
	236	extern unsigned int end_ftr_fixup_test1;
	237	extern unsigned int ftr_fixup_test1_orig;
	238	extern unsigned int ftr_fixup_test1_expected;
	239	int size = &end_ftr_fixup_test1 - &ftr_fixup_test1;
	240
	241	fixup.value = fixup.mask = 8;
	242	fixup.start_off = calc_offset(&fixup, &ftr_fixup_test1 + 1);
	243	fixup.end_off = calc_offset(&fixup, &ftr_fixup_test1 + 2);
	244	fixup.alt_start_off = fixup.alt_end_off = 0;
	245
	246	/* Sanity check */
	247	check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_orig, size) == 0);
	248
	249	/* Check we don't patch if the value matches */
	250	patch_feature_section(8, &fixup);
	251	check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_orig, size) == 0);
	252
	253	/* Check we do patch if the value doesn't match */
	254	patch_feature_section(0, &fixup);
	255	check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_expected, size) == 0);
	256
	257	/* Check we do patch if the mask doesn't match */
	258	memcpy(&ftr_fixup_test1, &ftr_fixup_test1_orig, size);
	259	check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_orig, size) == 0);
	260	patch_feature_section(~8, &fixup);
	261	check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_expected, size) == 0);
	262	}
	263
	264	static void test_alternative_patching(void)
	265	{
	266	extern unsigned int ftr_fixup_test2;
	267	extern unsigned int end_ftr_fixup_test2;
	268	extern unsigned int ftr_fixup_test2_orig;
	269	extern unsigned int ftr_fixup_test2_alt;
	270	extern unsigned int ftr_fixup_test2_expected;
	271	int size = &end_ftr_fixup_test2 - &ftr_fixup_test2;
	272
	273	fixup.value = fixup.mask = 0xF;
	274	fixup.start_off = calc_offset(&fixup, &ftr_fixup_test2 + 1);
	275	fixup.end_off = calc_offset(&fixup, &ftr_fixup_test2 + 2);
	276	fixup.alt_start_off = calc_offset(&fixup, &ftr_fixup_test2_alt);
	277	fixup.alt_end_off = calc_offset(&fixup, &ftr_fixup_test2_alt + 1);
	278
	279	/* Sanity check */
	280	check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_orig, size) == 0);
	281
	282	/* Check we don't patch if the value matches */
	283	patch_feature_section(0xF, &fixup);
	284	check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_orig, size) == 0);
	285
	286	/* Check we do patch if the value doesn't match */
	287	patch_feature_section(0, &fixup);
	288	check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_expected, size) == 0);
	289
	290	/* Check we do patch if the mask doesn't match */
	291	memcpy(&ftr_fixup_test2, &ftr_fixup_test2_orig, size);
	292	check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_orig, size) == 0);
	293	patch_feature_section(~0xF, &fixup);
	294	check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_expected, size) == 0);
	295	}
	296
	297	static void test_alternative_case_too_big(void)
298	{
299	extern unsigned int ftr_fixup_test3;
300	extern unsigned int end_ftr_fixup_test3;
301	extern unsigned int ftr_fixup_test3_orig;
302	extern unsigned int ftr_fixup_test3_alt;
303	int size = &end_ftr_fixup_test3 - &ftr_fixup_test3;
304
305	fixup.value = fixup.mask = 0xC;
306	fixup.start_off = calc_offset(&fixup, &ftr_fixup_test3 + 1);
307	fixup.end_off = calc_offset(&fixup, &ftr_fixup_test3 + 2);
308	fixup.alt_start_off = calc_offset(&fixup, &ftr_fixup_test3_alt);
309	fixup.alt_end_off = calc_offset(&fixup, &ftr_fixup_test3_alt + 2);
310
311	/* Sanity check */
312	check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0);
313
314	/* Expect nothing to be patched, and the error returned to us */
315	check(patch_feature_section(0xF, &fixup) == 1);
316	check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0);
317	check(patch_feature_section(0, &fixup) == 1);
318	check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0);
319	check(patch_feature_section(~0xF, &fixup) == 1);
320	check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0);
321	}
322
323	static void test_alternative_case_too_small(void)
324	{
325	extern unsigned int ftr_fixup_test4;
326	extern unsigned int end_ftr_fixup_test4;
327	extern unsigned int ftr_fixup_test4_orig;
328	extern unsigned int ftr_fixup_test4_alt;
329	extern unsigned int ftr_fixup_test4_expected;
330	int size = &end_ftr_fixup_test4 - &ftr_fixup_test4;
331	unsigned long flag;
332
333	/* Check a high-bit flag */
334	flag = 1UL << ((sizeof(unsigned long) - 1) * 8);
335	fixup.value = fixup.mask = flag;
336	fixup.start_off = calc_offset(&fixup, &ftr_fixup_test4 + 1);
337	fixup.end_off = calc_offset(&fixup, &ftr_fixup_test4 + 5);
338	fixup.alt_start_off = calc_offset(&fixup, &ftr_fixup_test4_alt);
339	fixup.alt_end_off = calc_offset(&fixup, &ftr_fixup_test4_alt + 2);
340
341	/* Sanity check */
342	check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_orig, size) == 0);
343
344	/* Check we don't patch if the value matches */
345	patch_feature_section(flag, &fixup);
346	check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_orig, size) == 0);
347
348	/* Check we do patch if the value doesn't match */
349	patch_feature_section(0, &fixup);
350	check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_expected, size) == 0);
351
352	/* Check we do patch if the mask doesn't match */
353	memcpy(&ftr_fixup_test4, &ftr_fixup_test4_orig, size);
354	check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_orig, size) == 0);
355	patch_feature_section(~flag, &fixup);
356	check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_expected, size) == 0);
357	}
358
359	static void test_alternative_case_with_branch(void)
360	{
361	extern unsigned int ftr_fixup_test5;
362	extern unsigned int end_ftr_fixup_test5;
363	extern unsigned int ftr_fixup_test5_expected;
364	int size = &end_ftr_fixup_test5 - &ftr_fixup_test5;
365
366	check(memcmp(&ftr_fixup_test5, &ftr_fixup_test5_expected, size) == 0);
367	}
368
369	static void test_alternative_case_with_external_branch(void)
370	{
371	extern unsigned int ftr_fixup_test6;
372	extern unsigned int end_ftr_fixup_test6;
373	extern unsigned int ftr_fixup_test6_expected;
374	int size = &end_ftr_fixup_test6 - &ftr_fixup_test6;
375
376	check(memcmp(&ftr_fixup_test6, &ftr_fixup_test6_expected, size) == 0);
377	}
378
379	static void test_cpu_macros(void)
380	{
3880ecb0 SR	381	extern u8 ftr_fixup_test_FTR_macros;
3880ecb0 SR	382	extern u8 ftr_fixup_test_FTR_macros_expected;
362e7701 ME	383	unsigned long size = &ftr_fixup_test_FTR_macros_expected -
	384	&ftr_fixup_test_FTR_macros;
	385
	386	/* The fixups have already been done for us during boot */
	387	check(memcmp(&ftr_fixup_test_FTR_macros,
	388	&ftr_fixup_test_FTR_macros_expected, size) == 0);
	389	}
	390
	391	static void test_fw_macros(void)
	392	{
	393	#ifdef CONFIG_PPC64
3880ecb0 SR	394	extern u8 ftr_fixup_test_FW_FTR_macros;
3880ecb0 SR	395	extern u8 ftr_fixup_test_FW_FTR_macros_expected;
362e7701 ME	396	unsigned long size = &ftr_fixup_test_FW_FTR_macros_expected -
	397	&ftr_fixup_test_FW_FTR_macros;
	398
	399	/* The fixups have already been done for us during boot */
	400	check(memcmp(&ftr_fixup_test_FW_FTR_macros,
	401	&ftr_fixup_test_FW_FTR_macros_expected, size) == 0);
	402	#endif
	403	}
	404
2d1b2027 KG	405	static void test_lwsync_macros(void)
2d1b2027 KG	406	{
3880ecb0 SR	407	extern u8 lwsync_fixup_test;
	408	extern u8 end_lwsync_fixup_test;
	409	extern u8 lwsync_fixup_test_expected_LWSYNC;
	410	extern u8 lwsync_fixup_test_expected_SYNC;
2d1b2027 KG	411	unsigned long size = &end_lwsync_fixup_test -
	412	&lwsync_fixup_test;
	413
	414	/* The fixups have already been done for us during boot */
	415	if (cur_cpu_spec->cpu_features & CPU_FTR_LWSYNC) {
	416	check(memcmp(&lwsync_fixup_test,
	417	&lwsync_fixup_test_expected_LWSYNC, size) == 0);
	418	} else {
	419	check(memcmp(&lwsync_fixup_test,
	420	&lwsync_fixup_test_expected_SYNC, size) == 0);
	421	}
	422	}
	423
362e7701 ME	424	static int __init test_feature_fixups(void)
	425	{
	426	printk(KERN_DEBUG "Running feature fixup self-tests ...\n");
	427
	428	test_basic_patching();
	429	test_alternative_patching();
	430	test_alternative_case_too_big();
	431	test_alternative_case_too_small();
	432	test_alternative_case_with_branch();
	433	test_alternative_case_with_external_branch();
	434	test_cpu_macros();
	435	test_fw_macros();
2d1b2027	436	test_lwsync_macros();
362e7701 ME	437
	438	return 0;
	439	}
	440	late_initcall(test_feature_fixups);
	441
	442	#endif /* CONFIG_FTR_FIXUP_SELFTEST */