[mirror_ubuntu-bionic-kernel.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 <linux/sched/mm.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));
		}
	}
}

#ifdef CONFIG_PPC_BOOK3S_64
void do_rfi_flush_fixups(enum l1d_flush_type types)
{
	unsigned int instrs[3], *dest;
	long *start, *end;
	int i;

	start = PTRRELOC(&__start___rfi_flush_fixup),
	end = PTRRELOC(&__stop___rfi_flush_fixup);

	instrs[0] = 0x60000000; /* nop */
	instrs[1] = 0x60000000; /* nop */
	instrs[2] = 0x60000000; /* nop */

	if (types & L1D_FLUSH_FALLBACK)
		/* b .+16 to fallback flush */
		instrs[0] = 0x48000010;

	i = 0;
	if (types & L1D_FLUSH_ORI) {
		instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
		instrs[i++] = 0x63de0000; /* ori 30,30,0 L1d flush*/
	}

	if (types & L1D_FLUSH_MTTRIG)
		instrs[i++] = 0x7c12dba6; /* mtspr TRIG2,r0 (SPR #882) */

	for (i = 0; start < end; start++, i++) {
		dest = (void *)start + *start;

		pr_devel("patching dest %lx\n", (unsigned long)dest);

		patch_instruction(dest, instrs[0]);
		patch_instruction(dest + 1, instrs[1]);
		patch_instruction(dest + 2, instrs[2]);
	}

	printk(KERN_DEBUG "rfi-flush: patched %d locations\n", i);
}
#endif /* CONFIG_PPC_BOOK3S_64 */

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>
589ee628	20	#include <linux/sched/mm.h>
51c52e86 ME	21	#include <asm/cputable.h>
51c52e86 ME	22	#include <asm/code-patching.h>
d715e433 AB	23	#include <asm/page.h>
d715e433 AB	24	#include <asm/sections.h>
9402c684 BH	25	#include <asm/setup.h>
9402c684 BH	26	#include <asm/firmware.h>
51c52e86 ME	27
	28	struct fixup_entry {
	29	unsigned long mask;
	30	unsigned long value;
	31	long start_off;
	32	long end_off;
fac23fe4 ME	33	long alt_start_off;
fac23fe4 ME	34	long alt_end_off;
51c52e86 ME	35	};
51c52e86 ME	36
9b1a735d	37	static unsigned int calc_addr(struct fixup_entry fcur, long offset)
51c52e86	38	{
9b1a735d ME	39	/*
	40	* We store the offset to the code as a negative offset from
	41	* the start of the alt_entry, to support the VDSO. This
	42	* routine converts that back into an actual address.
	43	*/
	44	return (unsigned int *)((unsigned long)fcur + offset);
	45	}
	46
	47	static int patch_alt_instruction(unsigned int src, unsigned int dest,
	48	unsigned int alt_start, unsigned int alt_end)
	49	{
	50	unsigned int instr;
	51
	52	instr = *src;
	53
	54	if (instr_is_relative_branch(*src)) {
	55	unsigned int target = (unsigned int )branch_target(src);
	56
	57	/* Branch within the section doesn't need translating */
	58	if (target < alt_start \|\| target >= alt_end) {
	59	instr = translate_branch(dest, src);
	60	if (!instr)
	61	return 1;
	62	}
	63	}
	64
	65	patch_instruction(dest, instr);
	66
	67	return 0;
	68	}
	69
	70	static int patch_feature_section(unsigned long value, struct fixup_entry *fcur)
	71	{
	72	unsigned int start, end, alt_start, alt_end, src, dest;
	73
	74	start = calc_addr(fcur, fcur->start_off);
	75	end = calc_addr(fcur, fcur->end_off);
	76	alt_start = calc_addr(fcur, fcur->alt_start_off);
	77	alt_end = calc_addr(fcur, fcur->alt_end_off);
	78
	79	if ((alt_end - alt_start) > (end - start))
	80	return 1;
51c52e86 ME	81
51c52e86 ME	82	if ((value & fcur->mask) == fcur->value)
9b1a735d	83	return 0;
51c52e86	84
9b1a735d ME	85	src = alt_start;
9b1a735d ME	86	dest = start;
51c52e86	87
9b1a735d ME	88	for (; src < alt_end; src++, dest++) {
	89	if (patch_alt_instruction(src, dest, alt_start, alt_end))
	90	return 1;
51c52e86	91	}
9b1a735d ME	92
9b1a735d ME	93	for (; dest < end; dest++)
16c57b36	94	patch_instruction(dest, PPC_INST_NOP);
9b1a735d ME	95
9b1a735d ME	96	return 0;
51c52e86 ME	97	}
	98
	99	void do_feature_fixups(unsigned long value, void fixup_start, void fixup_end)
	100	{
	101	struct fixup_entry fcur, fend;
	102
	103	fcur = fixup_start;
	104	fend = fixup_end;
	105
9b1a735d ME	106	for (; fcur < fend; fcur++) {
9b1a735d ME	107	if (patch_feature_section(value, fcur)) {
1856c020	108	WARN_ON(1);
9b1a735d ME	109	printk("Unable to patch feature section at %p - %p" \
	110	" with %p - %p\n",
	111	calc_addr(fcur, fcur->start_off),
	112	calc_addr(fcur, fcur->end_off),
	113	calc_addr(fcur, fcur->alt_start_off),
	114	calc_addr(fcur, fcur->alt_end_off));
	115	}
	116	}
51c52e86	117	}
362e7701	118
aa8a5e00 ME	119	#ifdef CONFIG_PPC_BOOK3S_64
	120	void do_rfi_flush_fixups(enum l1d_flush_type types)
	121	{
	122	unsigned int instrs[3], *dest;
	123	long start, end;
	124	int i;
	125
	126	start = PTRRELOC(&__start___rfi_flush_fixup),
	127	end = PTRRELOC(&__stop___rfi_flush_fixup);
	128
	129	instrs[0] = 0x60000000; /* nop */
	130	instrs[1] = 0x60000000; /* nop */
	131	instrs[2] = 0x60000000; /* nop */
	132
	133	if (types & L1D_FLUSH_FALLBACK)
	134	/* b .+16 to fallback flush */
	135	instrs[0] = 0x48000010;
	136
	137	i = 0;
	138	if (types & L1D_FLUSH_ORI) {
	139	instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
	140	instrs[i++] = 0x63de0000; /* ori 30,30,0 L1d flush*/
	141	}
	142
	143	if (types & L1D_FLUSH_MTTRIG)
	144	instrs[i++] = 0x7c12dba6; /* mtspr TRIG2,r0 (SPR #882) */
	145
	146	for (i = 0; start < end; start++, i++) {
	147	dest = (void )start + start;
	148
	149	pr_devel("patching dest %lx\n", (unsigned long)dest);
	150
	151	patch_instruction(dest, instrs[0]);
	152	patch_instruction(dest + 1, instrs[1]);
	153	patch_instruction(dest + 2, instrs[2]);
	154	}
	155
	156	printk(KERN_DEBUG "rfi-flush: patched %d locations\n", i);
	157	}
	158	#endif /* CONFIG_PPC_BOOK3S_64 */
	159
2d1b2027 KG	160	void do_lwsync_fixups(unsigned long value, void fixup_start, void fixup_end)
2d1b2027 KG	161	{
3d98ffbf BH	162	long start, end;
3d98ffbf BH	163	unsigned int *dest;
2d1b2027 KG	164
	165	if (!(value & CPU_FTR_LWSYNC))
	166	return ;
	167
	168	start = fixup_start;
	169	end = fixup_end;
	170
	171	for (; start < end; start++) {
	172	dest = (void )start + start;
16c57b36	173	patch_instruction(dest, PPC_INST_LWSYNC);
2d1b2027 KG	174	}
	175	}
	176
9402c684	177	static void do_final_fixups(void)
d715e433 AB	178	{
	179	#if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE)
	180	int src, dest;
	181	unsigned long length;
	182
	183	if (PHYSICAL_START == 0)
	184	return;
	185
	186	src = (int *)(KERNELBASE + PHYSICAL_START);
	187	dest = (int *)KERNELBASE;
	188	length = (__end_interrupts - _stext) / sizeof(int);
	189
	190	while (length--) {
	191	patch_instruction(dest, *src);
	192	src++;
	193	dest++;
	194	}
	195	#endif
	196	}
	197
a28e46f1 ME	198	static unsigned long __initdata saved_cpu_features;
	199	static unsigned int __initdata saved_mmu_features;
	200	#ifdef CONFIG_PPC64
	201	static unsigned long __initdata saved_firmware_features;
	202	#endif
	203
	204	void __init apply_feature_fixups(void)
9402c684	205	{
2c0f9951	206	struct cpu_spec spec = PTRRELOC(PTRRELOC(&cur_cpu_spec));
9402c684	207
a28e46f1 ME	208	*PTRRELOC(&saved_cpu_features) = spec->cpu_features;
	209	*PTRRELOC(&saved_mmu_features) = spec->mmu_features;
	210
9402c684 BH	211	/*
	212	* Apply the CPU-specific and firmware specific fixups to kernel text
	213	* (nop out sections not relevant to this CPU or this firmware).
	214	*/
	215	do_feature_fixups(spec->cpu_features,
	216	PTRRELOC(&__start___ftr_fixup),
	217	PTRRELOC(&__stop___ftr_fixup));
	218
	219	do_feature_fixups(spec->mmu_features,
	220	PTRRELOC(&__start___mmu_ftr_fixup),
	221	PTRRELOC(&__stop___mmu_ftr_fixup));
	222
	223	do_lwsync_fixups(spec->cpu_features,
	224	PTRRELOC(&__start___lwsync_fixup),
	225	PTRRELOC(&__stop___lwsync_fixup));
	226
	227	#ifdef CONFIG_PPC64
a28e46f1	228	saved_firmware_features = powerpc_firmware_features;
9402c684 BH	229	do_feature_fixups(powerpc_firmware_features,
	230	&__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
	231	#endif
	232	do_final_fixups();
97f6e0cc	233	}
309b315b	234
97f6e0cc BH	235	void __init setup_feature_keys(void)
97f6e0cc BH	236	{
309b315b AK	237	/*
	238	* Initialise jump label. This causes all the cpu/mmu_has_feature()
	239	* checks to take on their correct polarity based on the current set of
	240	* CPU/MMU features.
	241	*/
	242	jump_label_init();
4db73271	243	cpu_feature_keys_init();
c12e6f24	244	mmu_feature_keys_init();
9402c684 BH	245	}
9402c684 BH	246
a28e46f1 ME	247	static int __init check_features(void)
	248	{
	249	WARN(saved_cpu_features != cur_cpu_spec->cpu_features,
	250	"CPU features changed after feature patching!\n");
	251	WARN(saved_mmu_features != cur_cpu_spec->mmu_features,
	252	"MMU features changed after feature patching!\n");
	253	#ifdef CONFIG_PPC64
	254	WARN(saved_firmware_features != powerpc_firmware_features,
	255	"Firmware features changed after feature patching!\n");
	256	#endif
	257
	258	return 0;
	259	}
	260	late_initcall(check_features);
	261
362e7701 ME	262	#ifdef CONFIG_FTR_FIXUP_SELFTEST
	263
	264	#define check(x) \
	265	if (!(x)) printk("feature-fixups: test failed at line %d\n", __LINE__);
	266
	267	/* This must be after the text it fixes up, vmlinux.lds.S enforces that atm */
	268	static struct fixup_entry fixup;
	269
	270	static long calc_offset(struct fixup_entry entry, unsigned int p)
	271	{
	272	return (unsigned long)p - (unsigned long)entry;
	273	}
	274
e51df2c1	275	static void test_basic_patching(void)
362e7701	276	{
c69a48cd DA	277	extern unsigned int ftr_fixup_test1[];
	278	extern unsigned int end_ftr_fixup_test1[];
	279	extern unsigned int ftr_fixup_test1_orig[];
	280	extern unsigned int ftr_fixup_test1_expected[];
	281	int size = end_ftr_fixup_test1 - ftr_fixup_test1;
362e7701 ME	282
362e7701 ME	283	fixup.value = fixup.mask = 8;
c69a48cd DA	284	fixup.start_off = calc_offset(&fixup, ftr_fixup_test1 + 1);
c69a48cd DA	285	fixup.end_off = calc_offset(&fixup, ftr_fixup_test1 + 2);
362e7701 ME	286	fixup.alt_start_off = fixup.alt_end_off = 0;
	287
	288	/* Sanity check */
c69a48cd	289	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
362e7701 ME	290
	291	/* Check we don't patch if the value matches */
	292	patch_feature_section(8, &fixup);
c69a48cd	293	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
362e7701 ME	294
	295	/* Check we do patch if the value doesn't match */
	296	patch_feature_section(0, &fixup);
c69a48cd	297	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0);
362e7701 ME	298
362e7701 ME	299	/* Check we do patch if the mask doesn't match */
c69a48cd DA	300	memcpy(ftr_fixup_test1, ftr_fixup_test1_orig, size);
c69a48cd DA	301	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
362e7701	302	patch_feature_section(~8, &fixup);
c69a48cd	303	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0);
362e7701 ME	304	}
	305
	306	static void test_alternative_patching(void)
	307	{
c69a48cd DA	308	extern unsigned int ftr_fixup_test2[];
	309	extern unsigned int end_ftr_fixup_test2[];
	310	extern unsigned int ftr_fixup_test2_orig[];
	311	extern unsigned int ftr_fixup_test2_alt[];
	312	extern unsigned int ftr_fixup_test2_expected[];
	313	int size = end_ftr_fixup_test2 - ftr_fixup_test2;
362e7701 ME	314
362e7701 ME	315	fixup.value = fixup.mask = 0xF;
c69a48cd DA	316	fixup.start_off = calc_offset(&fixup, ftr_fixup_test2 + 1);
	317	fixup.end_off = calc_offset(&fixup, ftr_fixup_test2 + 2);
	318	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test2_alt);
	319	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test2_alt + 1);
362e7701 ME	320
362e7701 ME	321	/* Sanity check */
c69a48cd	322	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
362e7701 ME	323
	324	/* Check we don't patch if the value matches */
	325	patch_feature_section(0xF, &fixup);
c69a48cd	326	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
362e7701 ME	327
	328	/* Check we do patch if the value doesn't match */
	329	patch_feature_section(0, &fixup);
c69a48cd	330	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0);
362e7701 ME	331
362e7701 ME	332	/* Check we do patch if the mask doesn't match */
c69a48cd DA	333	memcpy(ftr_fixup_test2, ftr_fixup_test2_orig, size);
c69a48cd DA	334	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
362e7701	335	patch_feature_section(~0xF, &fixup);
c69a48cd	336	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0);
362e7701 ME	337	}
	338
	339	static void test_alternative_case_too_big(void)
	340	{
c69a48cd DA	341	extern unsigned int ftr_fixup_test3[];
	342	extern unsigned int end_ftr_fixup_test3[];
	343	extern unsigned int ftr_fixup_test3_orig[];
	344	extern unsigned int ftr_fixup_test3_alt[];
	345	int size = end_ftr_fixup_test3 - ftr_fixup_test3;
362e7701 ME	346
362e7701 ME	347	fixup.value = fixup.mask = 0xC;
c69a48cd DA	348	fixup.start_off = calc_offset(&fixup, ftr_fixup_test3 + 1);
	349	fixup.end_off = calc_offset(&fixup, ftr_fixup_test3 + 2);
	350	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test3_alt);
	351	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test3_alt + 2);
362e7701 ME	352
362e7701 ME	353	/* Sanity check */
c69a48cd	354	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
362e7701 ME	355
	356	/* Expect nothing to be patched, and the error returned to us */
	357	check(patch_feature_section(0xF, &fixup) == 1);
c69a48cd	358	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
362e7701	359	check(patch_feature_section(0, &fixup) == 1);
c69a48cd	360	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
362e7701	361	check(patch_feature_section(~0xF, &fixup) == 1);
c69a48cd	362	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
362e7701 ME	363	}
	364
	365	static void test_alternative_case_too_small(void)
	366	{
c69a48cd DA	367	extern unsigned int ftr_fixup_test4[];
	368	extern unsigned int end_ftr_fixup_test4[];
	369	extern unsigned int ftr_fixup_test4_orig[];
	370	extern unsigned int ftr_fixup_test4_alt[];
	371	extern unsigned int ftr_fixup_test4_expected[];
	372	int size = end_ftr_fixup_test4 - ftr_fixup_test4;
362e7701 ME	373	unsigned long flag;
	374
	375	/* Check a high-bit flag */
	376	flag = 1UL << ((sizeof(unsigned long) - 1) * 8);
	377	fixup.value = fixup.mask = flag;
c69a48cd DA	378	fixup.start_off = calc_offset(&fixup, ftr_fixup_test4 + 1);
	379	fixup.end_off = calc_offset(&fixup, ftr_fixup_test4 + 5);
	380	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test4_alt);
	381	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test4_alt + 2);
362e7701 ME	382
362e7701 ME	383	/* Sanity check */
c69a48cd	384	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
362e7701 ME	385
	386	/* Check we don't patch if the value matches */
	387	patch_feature_section(flag, &fixup);
c69a48cd	388	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
362e7701 ME	389
	390	/* Check we do patch if the value doesn't match */
	391	patch_feature_section(0, &fixup);
c69a48cd	392	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0);
362e7701 ME	393
362e7701 ME	394	/* Check we do patch if the mask doesn't match */
c69a48cd DA	395	memcpy(ftr_fixup_test4, ftr_fixup_test4_orig, size);
c69a48cd DA	396	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
362e7701	397	patch_feature_section(~flag, &fixup);
c69a48cd	398	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0);
362e7701 ME	399	}
	400
	401	static void test_alternative_case_with_branch(void)
	402	{
c69a48cd DA	403	extern unsigned int ftr_fixup_test5[];
	404	extern unsigned int end_ftr_fixup_test5[];
	405	extern unsigned int ftr_fixup_test5_expected[];
	406	int size = end_ftr_fixup_test5 - ftr_fixup_test5;
362e7701	407
c69a48cd	408	check(memcmp(ftr_fixup_test5, ftr_fixup_test5_expected, size) == 0);
362e7701 ME	409	}
	410
	411	static void test_alternative_case_with_external_branch(void)
	412	{
c69a48cd DA	413	extern unsigned int ftr_fixup_test6[];
	414	extern unsigned int end_ftr_fixup_test6[];
	415	extern unsigned int ftr_fixup_test6_expected[];
	416	int size = end_ftr_fixup_test6 - ftr_fixup_test6;
362e7701	417
c69a48cd	418	check(memcmp(ftr_fixup_test6, ftr_fixup_test6_expected, size) == 0);
362e7701 ME	419	}
	420
	421	static void test_cpu_macros(void)
	422	{
c69a48cd DA	423	extern u8 ftr_fixup_test_FTR_macros[];
	424	extern u8 ftr_fixup_test_FTR_macros_expected[];
	425	unsigned long size = ftr_fixup_test_FTR_macros_expected -
	426	ftr_fixup_test_FTR_macros;
362e7701 ME	427
362e7701 ME	428	/* The fixups have already been done for us during boot */
c69a48cd DA	429	check(memcmp(ftr_fixup_test_FTR_macros,
c69a48cd DA	430	ftr_fixup_test_FTR_macros_expected, size) == 0);
362e7701 ME	431	}
	432
	433	static void test_fw_macros(void)
	434	{
	435	#ifdef CONFIG_PPC64
c69a48cd DA	436	extern u8 ftr_fixup_test_FW_FTR_macros[];
	437	extern u8 ftr_fixup_test_FW_FTR_macros_expected[];
	438	unsigned long size = ftr_fixup_test_FW_FTR_macros_expected -
	439	ftr_fixup_test_FW_FTR_macros;
362e7701 ME	440
362e7701 ME	441	/* The fixups have already been done for us during boot */
c69a48cd DA	442	check(memcmp(ftr_fixup_test_FW_FTR_macros,
c69a48cd DA	443	ftr_fixup_test_FW_FTR_macros_expected, size) == 0);
362e7701 ME	444	#endif
	445	}
	446
2d1b2027 KG	447	static void test_lwsync_macros(void)
2d1b2027 KG	448	{
c69a48cd DA	449	extern u8 lwsync_fixup_test[];
	450	extern u8 end_lwsync_fixup_test[];
	451	extern u8 lwsync_fixup_test_expected_LWSYNC[];
	452	extern u8 lwsync_fixup_test_expected_SYNC[];
	453	unsigned long size = end_lwsync_fixup_test -
	454	lwsync_fixup_test;
2d1b2027 KG	455
	456	/* The fixups have already been done for us during boot */
	457	if (cur_cpu_spec->cpu_features & CPU_FTR_LWSYNC) {
c69a48cd DA	458	check(memcmp(lwsync_fixup_test,
c69a48cd DA	459	lwsync_fixup_test_expected_LWSYNC, size) == 0);
2d1b2027	460	} else {
c69a48cd DA	461	check(memcmp(lwsync_fixup_test,
c69a48cd DA	462	lwsync_fixup_test_expected_SYNC, size) == 0);
2d1b2027 KG	463	}
	464	}
	465
362e7701 ME	466	static int __init test_feature_fixups(void)
	467	{
	468	printk(KERN_DEBUG "Running feature fixup self-tests ...\n");
	469
	470	test_basic_patching();
	471	test_alternative_patching();
	472	test_alternative_case_too_big();
	473	test_alternative_case_too_small();
	474	test_alternative_case_with_branch();
	475	test_alternative_case_with_external_branch();
	476	test_cpu_macros();
	477	test_fw_macros();
2d1b2027	478	test_lwsync_macros();
362e7701 ME	479
	480	return 0;
	481	}
	482	late_initcall(test_feature_fixups);
	483
	484	#endif /* CONFIG_FTR_FIXUP_SELFTEST */