[mirror_ubuntu-bionic-kernel.git] / mm / early_ioremap.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Provide common bits of early_ioremap() support for architectures needing
 * temporary mappings during boot before ioremap() is available.
 *
 * This is mostly a direct copy of the x86 early_ioremap implementation.
 *
 * (C) Copyright 1995 1996, 2014 Linus Torvalds
 *
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <asm/fixmap.h>
#include <asm/early_ioremap.h>

#ifdef CONFIG_MMU
static int early_ioremap_debug __initdata;

static int __init early_ioremap_debug_setup(char *str)
{
	early_ioremap_debug = 1;

	return 0;
}
early_param("early_ioremap_debug", early_ioremap_debug_setup);

static int after_paging_init __initdata;

pgprot_t __init __weak early_memremap_pgprot_adjust(resource_size_t phys_addr,
						    unsigned long size,
						    pgprot_t prot)
{
	return prot;
}

void __init __weak early_ioremap_shutdown(void)
{
}

void __init early_ioremap_reset(void)
{
	early_ioremap_shutdown();
	after_paging_init = 1;
}

/*
 * Generally, ioremap() is available after paging_init() has been called.
 * Architectures wanting to allow early_ioremap after paging_init() can
 * define __late_set_fixmap and __late_clear_fixmap to do the right thing.
 */
#ifndef __late_set_fixmap
static inline void __init __late_set_fixmap(enum fixed_addresses idx,
					    phys_addr_t phys, pgprot_t prot)
{
	BUG();
}
#endif

#ifndef __late_clear_fixmap
static inline void __init __late_clear_fixmap(enum fixed_addresses idx)
{
	BUG();
}
#endif

static void __iomem *prev_map[FIX_BTMAPS_SLOTS] __initdata;
static unsigned long prev_size[FIX_BTMAPS_SLOTS] __initdata;
static unsigned long slot_virt[FIX_BTMAPS_SLOTS] __initdata;

void __init early_ioremap_setup(void)
{
	int i;

	for (i = 0; i < FIX_BTMAPS_SLOTS; i++)
		if (WARN_ON(prev_map[i]))
			break;

	for (i = 0; i < FIX_BTMAPS_SLOTS; i++)
		slot_virt[i] = __fix_to_virt(FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*i);
}

static int __init check_early_ioremap_leak(void)
{
	int count = 0;
	int i;

	for (i = 0; i < FIX_BTMAPS_SLOTS; i++)
		if (prev_map[i])
			count++;

	if (WARN(count, KERN_WARNING
		 "Debug warning: early ioremap leak of %d areas detected.\n"
		 "please boot with early_ioremap_debug and report the dmesg.\n",
		 count))
		return 1;
	return 0;
}
late_initcall(check_early_ioremap_leak);

static void __init __iomem *
__early_ioremap(resource_size_t phys_addr, unsigned long size, pgprot_t prot)
{
	unsigned long offset;
	resource_size_t last_addr;
	unsigned int nrpages;
	enum fixed_addresses idx;
	int i, slot;

	WARN_ON(system_state >= SYSTEM_RUNNING);

	slot = -1;
	for (i = 0; i < FIX_BTMAPS_SLOTS; i++) {
		if (!prev_map[i]) {
			slot = i;
			break;
		}
	}

	if (WARN(slot < 0, "%s(%08llx, %08lx) not found slot\n",
		 __func__, (u64)phys_addr, size))
		return NULL;

	/* Don't allow wraparound or zero size */
	last_addr = phys_addr + size - 1;
	if (WARN_ON(!size || last_addr < phys_addr))
		return NULL;

	prev_size[slot] = size;
	/*
	 * Mappings have to be page-aligned
	 */
	offset = offset_in_page(phys_addr);
	phys_addr &= PAGE_MASK;
	size = PAGE_ALIGN(last_addr + 1) - phys_addr;

	/*
	 * Mappings have to fit in the FIX_BTMAP area.
	 */
	nrpages = size >> PAGE_SHIFT;
	if (WARN_ON(nrpages > NR_FIX_BTMAPS))
		return NULL;

	/*
	 * Ok, go for it..
	 */
	idx = FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*slot;
	while (nrpages > 0) {
		if (after_paging_init)
			__late_set_fixmap(idx, phys_addr, prot);
		else
			__early_set_fixmap(idx, phys_addr, prot);
		phys_addr += PAGE_SIZE;
		--idx;
		--nrpages;
	}
	WARN(early_ioremap_debug, "%s(%08llx, %08lx) [%d] => %08lx + %08lx\n",
	     __func__, (u64)phys_addr, size, slot, offset, slot_virt[slot]);

	prev_map[slot] = (void __iomem *)(offset + slot_virt[slot]);
	return prev_map[slot];
}

void __init early_iounmap(void __iomem *addr, unsigned long size)
{
	unsigned long virt_addr;
	unsigned long offset;
	unsigned int nrpages;
	enum fixed_addresses idx;
	int i, slot;

	slot = -1;
	for (i = 0; i < FIX_BTMAPS_SLOTS; i++) {
		if (prev_map[i] == addr) {
			slot = i;
			break;
		}
	}

	if (WARN(slot < 0, "early_iounmap(%p, %08lx) not found slot\n",
		 addr, size))
		return;

	if (WARN(prev_size[slot] != size,
		 "early_iounmap(%p, %08lx) [%d] size not consistent %08lx\n",
		 addr, size, slot, prev_size[slot]))
		return;

	WARN(early_ioremap_debug, "early_iounmap(%p, %08lx) [%d]\n",
	     addr, size, slot);

	virt_addr = (unsigned long)addr;
	if (WARN_ON(virt_addr < fix_to_virt(FIX_BTMAP_BEGIN)))
		return;

	offset = offset_in_page(virt_addr);
	nrpages = PAGE_ALIGN(offset + size) >> PAGE_SHIFT;

	idx = FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*slot;
	while (nrpages > 0) {
		if (after_paging_init)
			__late_clear_fixmap(idx);
		else
			__early_set_fixmap(idx, 0, FIXMAP_PAGE_CLEAR);
		--idx;
		--nrpages;
	}
	prev_map[slot] = NULL;
}

/* Remap an IO device */
void __init __iomem *
early_ioremap(resource_size_t phys_addr, unsigned long size)
{
	return __early_ioremap(phys_addr, size, FIXMAP_PAGE_IO);
}

/* Remap memory */
void __init *
early_memremap(resource_size_t phys_addr, unsigned long size)
{
	pgprot_t prot = early_memremap_pgprot_adjust(phys_addr, size,
						     FIXMAP_PAGE_NORMAL);

	return (__force void *)__early_ioremap(phys_addr, size, prot);
}
#ifdef FIXMAP_PAGE_RO
void __init *
early_memremap_ro(resource_size_t phys_addr, unsigned long size)
{
	pgprot_t prot = early_memremap_pgprot_adjust(phys_addr, size,
						     FIXMAP_PAGE_RO);

	return (__force void *)__early_ioremap(phys_addr, size, prot);
}
#endif

#ifdef CONFIG_ARCH_USE_MEMREMAP_PROT
void __init *
early_memremap_prot(resource_size_t phys_addr, unsigned long size,
		    unsigned long prot_val)
{
	return (__force void *)__early_ioremap(phys_addr, size,
					       __pgprot(prot_val));
}
#endif

#define MAX_MAP_CHUNK	(NR_FIX_BTMAPS << PAGE_SHIFT)

void __init copy_from_early_mem(void *dest, phys_addr_t src, unsigned long size)
{
	unsigned long slop, clen;
	char *p;

	while (size) {
		slop = offset_in_page(src);
		clen = size;
		if (clen > MAX_MAP_CHUNK - slop)
			clen = MAX_MAP_CHUNK - slop;
		p = early_memremap(src & PAGE_MASK, clen + slop);
		memcpy(dest, p + slop, clen);
		early_memunmap(p, clen + slop);
		dest += clen;
		src += clen;
		size -= clen;
	}
}

#else /* CONFIG_MMU */

void __init __iomem *
early_ioremap(resource_size_t phys_addr, unsigned long size)
{
	return (__force void __iomem *)phys_addr;
}

/* Remap memory */
void __init *
early_memremap(resource_size_t phys_addr, unsigned long size)
{
	return (void *)phys_addr;
}
void __init *
early_memremap_ro(resource_size_t phys_addr, unsigned long size)
{
	return (void *)phys_addr;
}

void __init early_iounmap(void __iomem *addr, unsigned long size)
{
}

#endif /* CONFIG_MMU */


void __init early_memunmap(void *addr, unsigned long size)
{
	early_iounmap((__force void __iomem *)addr, size);
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
9e5c33d7 MS	2	/*
	3	* Provide common bits of early_ioremap() support for architectures needing
	4	* temporary mappings during boot before ioremap() is available.
	5	*
	6	* This is mostly a direct copy of the x86 early_ioremap implementation.
	7	*
	8	* (C) Copyright 1995 1996, 2014 Linus Torvalds
	9	*
	10	*/
	11	#include <linux/kernel.h>
	12	#include <linux/init.h>
	13	#include <linux/io.h>
	14	#include <linux/module.h>
	15	#include <linux/slab.h>
	16	#include <linux/mm.h>
	17	#include <linux/vmalloc.h>
	18	#include <asm/fixmap.h>
4f1af60b	19	#include <asm/early_ioremap.h>
9e5c33d7 MS	20
	21	#ifdef CONFIG_MMU
	22	static int early_ioremap_debug __initdata;
	23
	24	static int __init early_ioremap_debug_setup(char *str)
	25	{
	26	early_ioremap_debug = 1;
	27
	28	return 0;
	29	}
	30	early_param("early_ioremap_debug", early_ioremap_debug_setup);
	31
	32	static int after_paging_init __initdata;
	33
8f716c9b TL	34	pgprot_t __init __weak early_memremap_pgprot_adjust(resource_size_t phys_addr,
	35	unsigned long size,
	36	pgprot_t prot)
	37	{
	38	return prot;
	39	}
	40
9e5c33d7 MS	41	void __init __weak early_ioremap_shutdown(void)
	42	{
	43	}
	44
	45	void __init early_ioremap_reset(void)
	46	{
	47	early_ioremap_shutdown();
	48	after_paging_init = 1;
	49	}
	50
	51	/*
	52	* Generally, ioremap() is available after paging_init() has been called.
	53	* Architectures wanting to allow early_ioremap after paging_init() can
	54	* define __late_set_fixmap and __late_clear_fixmap to do the right thing.
	55	*/
	56	#ifndef __late_set_fixmap
	57	static inline void __init __late_set_fixmap(enum fixed_addresses idx,
	58	phys_addr_t phys, pgprot_t prot)
	59	{
	60	BUG();
	61	}
	62	#endif
	63
	64	#ifndef __late_clear_fixmap
	65	static inline void __init __late_clear_fixmap(enum fixed_addresses idx)
	66	{
	67	BUG();
	68	}
	69	#endif
	70
	71	static void __iomem *prev_map[FIX_BTMAPS_SLOTS] __initdata;
	72	static unsigned long prev_size[FIX_BTMAPS_SLOTS] __initdata;
	73	static unsigned long slot_virt[FIX_BTMAPS_SLOTS] __initdata;
	74
	75	void __init early_ioremap_setup(void)
	76	{
	77	int i;
	78
	79	for (i = 0; i < FIX_BTMAPS_SLOTS; i++)
	80	if (WARN_ON(prev_map[i]))
	81	break;
	82
	83	for (i = 0; i < FIX_BTMAPS_SLOTS; i++)
	84	slot_virt[i] = __fix_to_virt(FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*i);
	85	}
	86
	87	static int __init check_early_ioremap_leak(void)
	88	{
	89	int count = 0;
	90	int i;
	91
	92	for (i = 0; i < FIX_BTMAPS_SLOTS; i++)
	93	if (prev_map[i])
	94	count++;
	95
	96	if (WARN(count, KERN_WARNING
	97	"Debug warning: early ioremap leak of %d areas detected.\n"
	98	"please boot with early_ioremap_debug and report the dmesg.\n",
	99	count))
	100	return 1;
	101	return 0;
	102	}
	103	late_initcall(check_early_ioremap_leak);
	104
105	static void __init __iomem *
106	__early_ioremap(resource_size_t phys_addr, unsigned long size, pgprot_t prot)
107	{
108	unsigned long offset;
109	resource_size_t last_addr;
110	unsigned int nrpages;
111	enum fixed_addresses idx;
112	int i, slot;
113
7f6f60a1	114	WARN_ON(system_state >= SYSTEM_RUNNING);
9e5c33d7 MS	115
	116	slot = -1;
	117	for (i = 0; i < FIX_BTMAPS_SLOTS; i++) {
	118	if (!prev_map[i]) {
	119	slot = i;
	120	break;
	121	}
	122	}
	123
	124	if (WARN(slot < 0, "%s(%08llx, %08lx) not found slot\n",
	125	__func__, (u64)phys_addr, size))
	126	return NULL;
	127
	128	/* Don't allow wraparound or zero size */
	129	last_addr = phys_addr + size - 1;
	130	if (WARN_ON(!size \|\| last_addr < phys_addr))
	131	return NULL;
	132
	133	prev_size[slot] = size;
	134	/*
	135	* Mappings have to be page-aligned
	136	*/
5d57b014	137	offset = offset_in_page(phys_addr);
9e5c33d7 MS	138	phys_addr &= PAGE_MASK;
	139	size = PAGE_ALIGN(last_addr + 1) - phys_addr;
	140
	141	/*
	142	* Mappings have to fit in the FIX_BTMAP area.
	143	*/
	144	nrpages = size >> PAGE_SHIFT;
	145	if (WARN_ON(nrpages > NR_FIX_BTMAPS))
	146	return NULL;
	147
	148	/*
	149	* Ok, go for it..
	150	*/
	151	idx = FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*slot;
	152	while (nrpages > 0) {
	153	if (after_paging_init)
	154	__late_set_fixmap(idx, phys_addr, prot);
	155	else
	156	__early_set_fixmap(idx, phys_addr, prot);
	157	phys_addr += PAGE_SIZE;
	158	--idx;
	159	--nrpages;
	160	}
	161	WARN(early_ioremap_debug, "%s(%08llx, %08lx) [%d] => %08lx + %08lx\n",
	162	__func__, (u64)phys_addr, size, slot, offset, slot_virt[slot]);
	163
	164	prev_map[slot] = (void __iomem *)(offset + slot_virt[slot]);
	165	return prev_map[slot];
	166	}
	167
	168	void __init early_iounmap(void __iomem *addr, unsigned long size)
	169	{
	170	unsigned long virt_addr;
	171	unsigned long offset;
	172	unsigned int nrpages;
	173	enum fixed_addresses idx;
	174	int i, slot;
	175
	176	slot = -1;
	177	for (i = 0; i < FIX_BTMAPS_SLOTS; i++) {
	178	if (prev_map[i] == addr) {
	179	slot = i;
	180	break;
	181	}
	182	}
	183
	184	if (WARN(slot < 0, "early_iounmap(%p, %08lx) not found slot\n",
	185	addr, size))
	186	return;
	187
	188	if (WARN(prev_size[slot] != size,
	189	"early_iounmap(%p, %08lx) [%d] size not consistent %08lx\n",
	190	addr, size, slot, prev_size[slot]))
	191	return;
	192
	193	WARN(early_ioremap_debug, "early_iounmap(%p, %08lx) [%d]\n",
	194	addr, size, slot);
	195
	196	virt_addr = (unsigned long)addr;
	197	if (WARN_ON(virt_addr < fix_to_virt(FIX_BTMAP_BEGIN)))
	198	return;
	199
5d57b014	200	offset = offset_in_page(virt_addr);
9e5c33d7 MS	201	nrpages = PAGE_ALIGN(offset + size) >> PAGE_SHIFT;
	202
	203	idx = FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*slot;
	204	while (nrpages > 0) {
	205	if (after_paging_init)
	206	__late_clear_fixmap(idx);
	207	else
	208	__early_set_fixmap(idx, 0, FIXMAP_PAGE_CLEAR);
	209	--idx;
	210	--nrpages;
	211	}
	212	prev_map[slot] = NULL;
	213	}
	214
	215	/* Remap an IO device */
	216	void __init __iomem *
	217	early_ioremap(resource_size_t phys_addr, unsigned long size)
	218	{
	219	return __early_ioremap(phys_addr, size, FIXMAP_PAGE_IO);
	220	}
	221
	222	/* Remap memory */
	223	void __init *
	224	early_memremap(resource_size_t phys_addr, unsigned long size)
	225	{
8f716c9b TL	226	pgprot_t prot = early_memremap_pgprot_adjust(phys_addr, size,
	227	FIXMAP_PAGE_NORMAL);
	228
	229	return (__force void *)__early_ioremap(phys_addr, size, prot);
9e5c33d7	230	}
2592dbbb JG	231	#ifdef FIXMAP_PAGE_RO
	232	void __init *
	233	early_memremap_ro(resource_size_t phys_addr, unsigned long size)
	234	{
8f716c9b TL	235	pgprot_t prot = early_memremap_pgprot_adjust(phys_addr, size,
	236	FIXMAP_PAGE_RO);
	237
	238	return (__force void *)__early_ioremap(phys_addr, size, prot);
2592dbbb JG	239	}
2592dbbb JG	240	#endif
6b0f68e3	241
f88a68fa TL	242	#ifdef CONFIG_ARCH_USE_MEMREMAP_PROT
	243	void __init *
	244	early_memremap_prot(resource_size_t phys_addr, unsigned long size,
	245	unsigned long prot_val)
	246	{
	247	return (__force void *)__early_ioremap(phys_addr, size,
	248	__pgprot(prot_val));
	249	}
	250	#endif
	251
6b0f68e3 MS	252	#define MAX_MAP_CHUNK (NR_FIX_BTMAPS << PAGE_SHIFT)
	253
	254	void __init copy_from_early_mem(void *dest, phys_addr_t src, unsigned long size)
	255	{
	256	unsigned long slop, clen;
	257	char *p;
	258
	259	while (size) {
5d57b014	260	slop = offset_in_page(src);
6b0f68e3 MS	261	clen = size;
	262	if (clen > MAX_MAP_CHUNK - slop)
	263	clen = MAX_MAP_CHUNK - slop;
	264	p = early_memremap(src & PAGE_MASK, clen + slop);
	265	memcpy(dest, p + slop, clen);
	266	early_memunmap(p, clen + slop);
	267	dest += clen;
	268	src += clen;
	269	size -= clen;
	270	}
	271	}
	272
9e5c33d7 MS	273	#else /* CONFIG_MMU */
	274
	275	void __init __iomem *
	276	early_ioremap(resource_size_t phys_addr, unsigned long size)
	277	{
	278	return (__force void __iomem *)phys_addr;
	279	}
	280
	281	/* Remap memory */
	282	void __init *
	283	early_memremap(resource_size_t phys_addr, unsigned long size)
	284	{
	285	return (void *)phys_addr;
	286	}
2592dbbb JG	287	void __init *
	288	early_memremap_ro(resource_size_t phys_addr, unsigned long size)
	289	{
	290	return (void *)phys_addr;
	291	}
9e5c33d7 MS	292
	293	void __init early_iounmap(void __iomem *addr, unsigned long size)
	294	{
	295	}
	296
	297	#endif /* CONFIG_MMU */
	298
	299
	300	void __init early_memunmap(void *addr, unsigned long size)
	301	{
	302	early_iounmap((__force void __iomem *)addr, size);
	303	}