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

/*
 * 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_BOOTING);

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