arch/sparc/kernel/ioport.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * ioport.c:  Simple io mapping allocator.
  *
  * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
  * Copyright (C) 1995 Miguel de Icaza (miguel@nuclecu.unam.mx)
  *
  * 1996: sparc_free_io, 1999: ioremap()/iounmap() by Pete Zaitcev.
  *
  * 2000/01/29
  * <rth> zait: as long as pci_alloc_consistent produces something addressable,
  *	things are ok.
  * <zaitcev> rth: no, it is relevant, because get_free_pages returns you a
  *	pointer into the big page mapping
  * <rth> zait: so what?
  * <rth> zait: remap_it_my_way(virt_to_phys(get_free_page()))
  * <zaitcev> Hmm
  * <zaitcev> Suppose I did this remap_it_my_way(virt_to_phys(get_free_page())).
  *	So far so good.
  * <zaitcev> Now, driver calls pci_free_consistent(with result of
  *	remap_it_my_way()).
  * <zaitcev> How do you find the address to pass to free_pages()?
  * <rth> zait: walk the page tables?  It's only two or three level after all.
  * <rth> zait: you have to walk them anyway to remove the mapping.
  * <zaitcev> Hmm
  * <zaitcev> Sounds reasonable
  */

 #include <linux/module.h>
 #include <linux/sched.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/types.h>
 #include <linux/ioport.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
 #include <linux/pci.h>		/* struct pci_dev */
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 #include <linux/scatterlist.h>
 #include <linux/dma-map-ops.h>
 #include <linux/of.h>

 #include <asm/io.h>
 #include <asm/vaddrs.h>
 #include <asm/oplib.h>
 #include <asm/prom.h>
 #include <asm/page.h>
 #include <asm/pgalloc.h>
 #include <asm/dma.h>
 #include <asm/iommu.h>
 #include <asm/io-unit.h>
 #include <asm/leon.h>

 static void __iomem *_sparc_ioremap(struct resource *res, u32 bus, u32 pa, int sz);
 static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys,
     unsigned long size, char *name);
 static void _sparc_free_io(struct resource *res);

 static void register_proc_sparc_ioport(void);

 /* This points to the next to use virtual memory for DVMA mappings */
 static struct resource _sparc_dvma = {
 	.name = "sparc_dvma", .start = DVMA_VADDR, .end = DVMA_END - 1
 };
 /* This points to the start of I/O mappings, cluable from outside. */
 /*ext*/ struct resource sparc_iomap = {
 	.name = "sparc_iomap", .start = IOBASE_VADDR, .end = IOBASE_END - 1
 };

 /*
  * Our mini-allocator...
  * Boy this is gross! We need it because we must map I/O for
  * timers and interrupt controller before the kmalloc is available.
  */

 #define XNMLN  15
 #define XNRES  10	/* SS-10 uses 8 */

 struct xresource {
 	struct resource xres;	/* Must be first */
 	int xflag;		/* 1 == used */
 	char xname[XNMLN+1];
 };

 static struct xresource xresv[XNRES];

 static struct xresource *xres_alloc(void) {
 	struct xresource *xrp;
 	int n;

 	xrp = xresv;
 	for (n = 0; n < XNRES; n++) {
 		if (xrp->xflag == 0) {
 			xrp->xflag = 1;
 			return xrp;
 		}
 		xrp++;
 	}
 	return NULL;
 }

 static void xres_free(struct xresource *xrp) {
 	xrp->xflag = 0;
 }

 /*
  * These are typically used in PCI drivers
  * which are trying to be cross-platform.
  *
  * Bus type is always zero on IIep.
  */
 void __iomem *ioremap(phys_addr_t offset, size_t size)
 {
 	char name[14];

 	sprintf(name, "phys_%08x", (u32)offset);
 	return _sparc_alloc_io(0, (unsigned long)offset, size, name);
 }
 EXPORT_SYMBOL(ioremap);

 /*
  * Complementary to ioremap().
  */
 void iounmap(volatile void __iomem *virtual)
 {
 	unsigned long vaddr = (unsigned long) virtual & PAGE_MASK;
 	struct resource *res;

 	/*
 	 * XXX Too slow. Can have 8192 DVMA pages on sun4m in the worst case.
 	 * This probably warrants some sort of hashing.
 	*/
 	if ((res = lookup_resource(&sparc_iomap, vaddr)) == NULL) {
 		printk("free_io/iounmap: cannot free %lx\n", vaddr);
 		return;
 	}
 	_sparc_free_io(res);

 	if ((char *)res >= (char*)xresv && (char *)res < (char *)&xresv[XNRES]) {
 		xres_free((struct xresource *)res);
 	} else {
 		kfree(res);
 	}
 }
 EXPORT_SYMBOL(iounmap);

 void __iomem *of_ioremap(struct resource *res, unsigned long offset,
 			 unsigned long size, char *name)
 {
 	return _sparc_alloc_io(res->flags & 0xF,
 			       res->start + offset,
 			       size, name);
 }
 EXPORT_SYMBOL(of_ioremap);

 void of_iounmap(struct resource *res, void __iomem *base, unsigned long size)
 {
 	iounmap(base);
 }
 EXPORT_SYMBOL(of_iounmap);

 /*
  * Meat of mapping
  */
 static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys,
     unsigned long size, char *name)
 {
 	static int printed_full;
 	struct xresource *xres;
 	struct resource *res;
 	char *tack;
 	int tlen;
 	void __iomem *va;	/* P3 diag */

 	if (name == NULL) name = "???";

 	if ((xres = xres_alloc()) != NULL) {
 		tack = xres->xname;
 		res = &xres->xres;
 	} else {
 		if (!printed_full) {
 			printk("ioremap: done with statics, switching to malloc\n");
 			printed_full = 1;
 		}
 		tlen = strlen(name);
 		tack = kmalloc(sizeof (struct resource) + tlen + 1, GFP_KERNEL);
 		if (tack == NULL) return NULL;
 		memset(tack, 0, sizeof(struct resource));
 		res = (struct resource *) tack;
 		tack += sizeof (struct resource);
 	}

 	strscpy(tack, name, XNMLN+1);
 	res->name = tack;

 	va = _sparc_ioremap(res, busno, phys, size);
 	/* printk("ioremap(0x%x:%08lx[0x%lx])=%p\n", busno, phys, size, va); */ /* P3 diag */
 	return va;
 }

 /*
  */
 static void __iomem *
 _sparc_ioremap(struct resource *res, u32 bus, u32 pa, int sz)
 {
 	unsigned long offset = ((unsigned long) pa) & (~PAGE_MASK);

 	if (allocate_resource(&sparc_iomap, res,
 	    (offset + sz + PAGE_SIZE-1) & PAGE_MASK,
 	    sparc_iomap.start, sparc_iomap.end, PAGE_SIZE, NULL, NULL) != 0) {
 		/* Usually we cannot see printks in this case. */
 		prom_printf("alloc_io_res(%s): cannot occupy\n",
 		    (res->name != NULL)? res->name: "???");
 		prom_halt();
 	}

 	pa &= PAGE_MASK;
 	srmmu_mapiorange(bus, pa, res->start, resource_size(res));

 	return (void __iomem *)(unsigned long)(res->start + offset);
 }

 /*
  * Complementary to _sparc_ioremap().
  */
 static void _sparc_free_io(struct resource *res)
 {
 	unsigned long plen;

 	plen = resource_size(res);
 	BUG_ON((plen & (PAGE_SIZE-1)) != 0);
 	srmmu_unmapiorange(res->start, plen);
 	release_resource(res);
 }

 unsigned long sparc_dma_alloc_resource(struct device *dev, size_t len)
 {
 	struct resource *res;

 	res = kzalloc(sizeof(*res), GFP_KERNEL);
 	if (!res)
 		return 0;
 	res->name = dev->of_node->full_name;

 	if (allocate_resource(&_sparc_dvma, res, len, _sparc_dvma.start,
 			      _sparc_dvma.end, PAGE_SIZE, NULL, NULL) != 0) {
 		printk("%s: cannot occupy 0x%zx", __func__, len);
 		kfree(res);
 		return 0;
 	}

 	return res->start;
 }

 bool sparc_dma_free_resource(void *cpu_addr, size_t size)
 {
 	unsigned long addr = (unsigned long)cpu_addr;
 	struct resource *res;

 	res = lookup_resource(&_sparc_dvma, addr);
 	if (!res) {
 		printk("%s: cannot free %p\n", __func__, cpu_addr);
 		return false;
 	}

 	if ((addr & (PAGE_SIZE - 1)) != 0) {
 		printk("%s: unaligned va %p\n", __func__, cpu_addr);
 		return false;
 	}

 	size = PAGE_ALIGN(size);
 	if (resource_size(res) != size) {
 		printk("%s: region 0x%lx asked 0x%zx\n",
 			__func__, (long)resource_size(res), size);
 		return false;
 	}

 	release_resource(res);
 	kfree(res);
 	return true;
 }

 #ifdef CONFIG_SBUS

 void sbus_set_sbus64(struct device *dev, int x)
 {
 	printk("sbus_set_sbus64: unsupported\n");
 }
 EXPORT_SYMBOL(sbus_set_sbus64);

 static int __init sparc_register_ioport(void)
 {
 	register_proc_sparc_ioport();

 	return 0;
 }

 arch_initcall(sparc_register_ioport);

 #endif /* CONFIG_SBUS */

 /*
  * IIep is write-through, not flushing on cpu to device transfer.
  *
  * On LEON systems without cache snooping, the entire D-CACHE must be flushed to
  * make DMA to cacheable memory coherent.
  */
 void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
 		enum dma_data_direction dir)
 {
 	if (dir != DMA_TO_DEVICE &&
 	    sparc_cpu_model == sparc_leon &&
 	    !sparc_leon3_snooping_enabled())
 		leon_flush_dcache_all();
 }

 #ifdef CONFIG_PROC_FS

 static int sparc_io_proc_show(struct seq_file *m, void *v)
 {
 	struct resource *root = m->private, *r;
 	const char *nm;

 	for (r = root->child; r != NULL; r = r->sibling) {
 		if ((nm = r->name) == NULL) nm = "???";
 		seq_printf(m, "%016llx-%016llx: %s\n",
 				(unsigned long long)r->start,
 				(unsigned long long)r->end, nm);
 	}

 	return 0;
 }
 #endif /* CONFIG_PROC_FS */

 static void register_proc_sparc_ioport(void)
 {
 #ifdef CONFIG_PROC_FS
 	proc_create_single_data("io_map", 0, NULL, sparc_io_proc_show,
 			&sparc_iomap);
 	proc_create_single_data("dvma_map", 0, NULL, sparc_io_proc_show,
 			&_sparc_dvma);
 #endif
 }
	// SPDX-License-Identifier: GPL-2.0
	/*
	* ioport.c: Simple io mapping allocator.
	*
	* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
	* Copyright (C) 1995 Miguel de Icaza (miguel@nuclecu.unam.mx)
	*
	* 1996: sparc_free_io, 1999: ioremap()/iounmap() by Pete Zaitcev.
	*
	* 2000/01/29
	* <rth> zait: as long as pci_alloc_consistent produces something addressable,
	* things are ok.
	* <zaitcev> rth: no, it is relevant, because get_free_pages returns you a
	* pointer into the big page mapping
	* <rth> zait: so what?
	* <rth> zait: remap_it_my_way(virt_to_phys(get_free_page()))
	* <zaitcev> Hmm
	* <zaitcev> Suppose I did this remap_it_my_way(virt_to_phys(get_free_page())).
	* So far so good.
	* <zaitcev> Now, driver calls pci_free_consistent(with result of
	* remap_it_my_way()).
	* <zaitcev> How do you find the address to pass to free_pages()?
	* <rth> zait: walk the page tables? It's only two or three level after all.
	* <rth> zait: you have to walk them anyway to remove the mapping.
	* <zaitcev> Hmm
	* <zaitcev> Sounds reasonable
	*/

	#include <linux/module.h>
	#include <linux/sched.h>
	#include <linux/kernel.h>
	#include <linux/errno.h>
	#include <linux/types.h>
	#include <linux/ioport.h>
	#include <linux/mm.h>
	#include <linux/slab.h>
	#include <linux/pci.h> /* struct pci_dev */
	#include <linux/proc_fs.h>
	#include <linux/seq_file.h>
	#include <linux/scatterlist.h>
	#include <linux/dma-map-ops.h>
	#include <linux/of.h>

	#include <asm/io.h>
	#include <asm/vaddrs.h>
	#include <asm/oplib.h>
	#include <asm/prom.h>
	#include <asm/page.h>
	#include <asm/pgalloc.h>
	#include <asm/dma.h>
	#include <asm/iommu.h>
	#include <asm/io-unit.h>
	#include <asm/leon.h>

	static void __iomem _sparc_ioremap(struct resource res, u32 bus, u32 pa, int sz);
	static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys,
	unsigned long size, char *name);
	static void _sparc_free_io(struct resource *res);

	static void register_proc_sparc_ioport(void);

	/* This points to the next to use virtual memory for DVMA mappings */
	static struct resource _sparc_dvma = {
	.name = "sparc_dvma", .start = DVMA_VADDR, .end = DVMA_END - 1
	};
	/* This points to the start of I/O mappings, cluable from outside. */
	/ext/ struct resource sparc_iomap = {
	.name = "sparc_iomap", .start = IOBASE_VADDR, .end = IOBASE_END - 1
	};

	/*
	* Our mini-allocator...
	* Boy this is gross! We need it because we must map I/O for
	* timers and interrupt controller before the kmalloc is available.
	*/

	#define XNMLN 15
	#define XNRES 10 /* SS-10 uses 8 */

	struct xresource {
	struct resource xres; /* Must be first */
	int xflag; /* 1 == used */
	char xname[XNMLN+1];
	};

	static struct xresource xresv[XNRES];

	static struct xresource *xres_alloc(void) {
	struct xresource *xrp;
	int n;

	xrp = xresv;
	for (n = 0; n < XNRES; n++) {
	if (xrp->xflag == 0) {
	xrp->xflag = 1;
	return xrp;
	}
	xrp++;
	}
	return NULL;
	}

	static void xres_free(struct xresource *xrp) {
	xrp->xflag = 0;
	}

	/*
	* These are typically used in PCI drivers
	* which are trying to be cross-platform.
	*
	* Bus type is always zero on IIep.
	*/
	void __iomem *ioremap(phys_addr_t offset, size_t size)
	{
	char name[14];

	sprintf(name, "phys_%08x", (u32)offset);
	return _sparc_alloc_io(0, (unsigned long)offset, size, name);
	}
	EXPORT_SYMBOL(ioremap);

	/*
	* Complementary to ioremap().
	*/
	void iounmap(volatile void __iomem *virtual)
	{
	unsigned long vaddr = (unsigned long) virtual & PAGE_MASK;
	struct resource *res;

	/*
	* XXX Too slow. Can have 8192 DVMA pages on sun4m in the worst case.
	* This probably warrants some sort of hashing.
	*/
	if ((res = lookup_resource(&sparc_iomap, vaddr)) == NULL) {
	printk("free_io/iounmap: cannot free %lx\n", vaddr);
	return;
	}
	_sparc_free_io(res);

	if ((char )res >= (char)xresv && (char )res < (char )&xresv[XNRES]) {
	xres_free((struct xresource *)res);
	} else {
	kfree(res);
	}
	}
	EXPORT_SYMBOL(iounmap);

	void __iomem of_ioremap(struct resource res, unsigned long offset,
	unsigned long size, char *name)
	{
	return _sparc_alloc_io(res->flags & 0xF,
	res->start + offset,
	size, name);
	}
	EXPORT_SYMBOL(of_ioremap);

	void of_iounmap(struct resource res, void __iomem base, unsigned long size)
	{
	iounmap(base);
	}
	EXPORT_SYMBOL(of_iounmap);

	/*
	* Meat of mapping
	*/
	static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys,
	unsigned long size, char *name)
	{
	static int printed_full;
	struct xresource *xres;
	struct resource *res;
	char *tack;
	int tlen;
	void __iomem va; / P3 diag */

	if (name == NULL) name = "???";

	if ((xres = xres_alloc()) != NULL) {
	tack = xres->xname;
	res = &xres->xres;
	} else {
	if (!printed_full) {
	printk("ioremap: done with statics, switching to malloc\n");
	printed_full = 1;
	}
	tlen = strlen(name);
	tack = kmalloc(sizeof (struct resource) + tlen + 1, GFP_KERNEL);
	if (tack == NULL) return NULL;
	memset(tack, 0, sizeof(struct resource));
	res = (struct resource *) tack;
	tack += sizeof (struct resource);
	}

	strscpy(tack, name, XNMLN+1);
	res->name = tack;

	va = _sparc_ioremap(res, busno, phys, size);
	/* printk("ioremap(0x%x:%08lx[0x%lx])=%p\n", busno, phys, size, va); / / P3 diag */
	return va;
	}

	/*
	*/
	static void __iomem *
	_sparc_ioremap(struct resource *res, u32 bus, u32 pa, int sz)
	{
	unsigned long offset = ((unsigned long) pa) & (~PAGE_MASK);

	if (allocate_resource(&sparc_iomap, res,
	(offset + sz + PAGE_SIZE-1) & PAGE_MASK,
	sparc_iomap.start, sparc_iomap.end, PAGE_SIZE, NULL, NULL) != 0) {
	/* Usually we cannot see printks in this case. */
	prom_printf("alloc_io_res(%s): cannot occupy\n",
	(res->name != NULL)? res->name: "???");
	prom_halt();
	}

	pa &= PAGE_MASK;
	srmmu_mapiorange(bus, pa, res->start, resource_size(res));

	return (void __iomem *)(unsigned long)(res->start + offset);
	}

	/*
	* Complementary to _sparc_ioremap().
	*/
	static void _sparc_free_io(struct resource *res)
	{
	unsigned long plen;

	plen = resource_size(res);
	BUG_ON((plen & (PAGE_SIZE-1)) != 0);
	srmmu_unmapiorange(res->start, plen);
	release_resource(res);
	}

	unsigned long sparc_dma_alloc_resource(struct device *dev, size_t len)
	{
	struct resource *res;

	res = kzalloc(sizeof(*res), GFP_KERNEL);
	if (!res)
	return 0;
	res->name = dev->of_node->full_name;

	if (allocate_resource(&_sparc_dvma, res, len, _sparc_dvma.start,
	_sparc_dvma.end, PAGE_SIZE, NULL, NULL) != 0) {
	printk("%s: cannot occupy 0x%zx", __func__, len);
	kfree(res);
	return 0;
	}

	return res->start;
	}

	bool sparc_dma_free_resource(void *cpu_addr, size_t size)
	{
	unsigned long addr = (unsigned long)cpu_addr;
	struct resource *res;

	res = lookup_resource(&_sparc_dvma, addr);
	if (!res) {
	printk("%s: cannot free %p\n", __func__, cpu_addr);
	return false;
	}

	if ((addr & (PAGE_SIZE - 1)) != 0) {
	printk("%s: unaligned va %p\n", __func__, cpu_addr);
	return false;
	}

	size = PAGE_ALIGN(size);
	if (resource_size(res) != size) {
	printk("%s: region 0x%lx asked 0x%zx\n",
	__func__, (long)resource_size(res), size);
	return false;
	}

	release_resource(res);
	kfree(res);
	return true;
	}

	#ifdef CONFIG_SBUS

	void sbus_set_sbus64(struct device *dev, int x)
	{
	printk("sbus_set_sbus64: unsupported\n");
	}
	EXPORT_SYMBOL(sbus_set_sbus64);

	static int __init sparc_register_ioport(void)
	{
	register_proc_sparc_ioport();

	return 0;
	}

	arch_initcall(sparc_register_ioport);

	#endif /* CONFIG_SBUS */

	/*
	* IIep is write-through, not flushing on cpu to device transfer.
	*
	* On LEON systems without cache snooping, the entire D-CACHE must be flushed to
	* make DMA to cacheable memory coherent.
	*/
	void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
	enum dma_data_direction dir)
	{
	if (dir != DMA_TO_DEVICE &&
	sparc_cpu_model == sparc_leon &&
	!sparc_leon3_snooping_enabled())
	leon_flush_dcache_all();
	}

	#ifdef CONFIG_PROC_FS

	static int sparc_io_proc_show(struct seq_file m, void v)
	{
	struct resource root = m->private, r;
	const char *nm;

	for (r = root->child; r != NULL; r = r->sibling) {
	if ((nm = r->name) == NULL) nm = "???";
	seq_printf(m, "%016llx-%016llx: %s\n",
	(unsigned long long)r->start,
	(unsigned long long)r->end, nm);
	}

	return 0;
	}
	#endif /* CONFIG_PROC_FS */

	static void register_proc_sparc_ioport(void)
	{
	#ifdef CONFIG_PROC_FS
	proc_create_single_data("io_map", 0, NULL, sparc_io_proc_show,
	&sparc_iomap);
	proc_create_single_data("dvma_map", 0, NULL, sparc_io_proc_show,
	&_sparc_dvma);
	#endif
	}