lib/logic_pio.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright (C) 2017 HiSilicon Limited, All Rights Reserved.
  * Author: Gabriele Paoloni <gabriele.paoloni@huawei.com>
  * Author: Zhichang Yuan <yuanzhichang@hisilicon.com>
  * Author: John Garry <john.garry@huawei.com>
  */

 #define pr_fmt(fmt)	"LOGIC PIO: " fmt

 #include <linux/of.h>
 #include <linux/io.h>
 #include <linux/logic_pio.h>
 #include <linux/mm.h>
 #include <linux/rculist.h>
 #include <linux/sizes.h>
 #include <linux/slab.h>

 /* The unique hardware address list */
 static LIST_HEAD(io_range_list);
 static DEFINE_MUTEX(io_range_mutex);

 /**
  * logic_pio_register_range - register logical PIO range for a host
  * @new_range: pointer to the IO range to be registered.
  *
  * Returns 0 on success, the error code in case of failure.
  * If the range already exists, -EEXIST will be returned, which should be
  * considered a success.
  *
  * Register a new IO range node in the IO range list.
  */
 int logic_pio_register_range(struct logic_pio_hwaddr *new_range)
 {
 	struct logic_pio_hwaddr *range;
 	resource_size_t start;
 	resource_size_t end;
 	resource_size_t mmio_end = 0;
 	resource_size_t iio_sz = MMIO_UPPER_LIMIT;
 	int ret = 0;

 	if (!new_range || !new_range->fwnode || !new_range->size ||
 	    (new_range->flags == LOGIC_PIO_INDIRECT && !new_range->ops))
 		return -EINVAL;

 	start = new_range->hw_start;
 	end = new_range->hw_start + new_range->size;

 	mutex_lock(&io_range_mutex);
 	list_for_each_entry(range, &io_range_list, list) {
 		if (range->fwnode == new_range->fwnode) {
 			/* range already there */
 			ret = -EEXIST;
 			goto end_register;
 		}
 		if (range->flags == LOGIC_PIO_CPU_MMIO &&
 		    new_range->flags == LOGIC_PIO_CPU_MMIO) {
 			/* for MMIO ranges we need to check for overlap */
 			if (start >= range->hw_start + range->size ||
 			    end < range->hw_start) {
 				mmio_end = range->io_start + range->size;
 			} else {
 				ret = -EFAULT;
 				goto end_register;
 			}
 		} else if (range->flags == LOGIC_PIO_INDIRECT &&
 			   new_range->flags == LOGIC_PIO_INDIRECT) {
 			iio_sz += range->size;
 		}
 	}

 	/* range not registered yet, check for available space */
 	if (new_range->flags == LOGIC_PIO_CPU_MMIO) {
 		if (mmio_end + new_range->size - 1 > MMIO_UPPER_LIMIT) {
 			/* if it's too big check if 64K space can be reserved */
 			if (mmio_end + SZ_64K - 1 > MMIO_UPPER_LIMIT) {
 				ret = -E2BIG;
 				goto end_register;
 			}
 			new_range->size = SZ_64K;
 			pr_warn("Requested IO range too big, new size set to 64K\n");
 		}
 		new_range->io_start = mmio_end;
 	} else if (new_range->flags == LOGIC_PIO_INDIRECT) {
 		if (iio_sz + new_range->size - 1 > IO_SPACE_LIMIT) {
 			ret = -E2BIG;
 			goto end_register;
 		}
 		new_range->io_start = iio_sz;
 	} else {
 		/* invalid flag */
 		ret = -EINVAL;
 		goto end_register;
 	}

 	list_add_tail_rcu(&new_range->list, &io_range_list);

 end_register:
 	mutex_unlock(&io_range_mutex);
 	return ret;
 }

 /**
  * logic_pio_unregister_range - unregister a logical PIO range for a host
  * @range: pointer to the IO range which has been already registered.
  *
  * Unregister a previously-registered IO range node.
  */
 void logic_pio_unregister_range(struct logic_pio_hwaddr *range)
 {
 	mutex_lock(&io_range_mutex);
 	list_del_rcu(&range->list);
 	mutex_unlock(&io_range_mutex);
 	synchronize_rcu();
 }

 /**
  * find_io_range_by_fwnode - find logical PIO range for given FW node
  * @fwnode: FW node handle associated with logical PIO range
  *
  * Returns pointer to node on success, NULL otherwise.
  *
  * Traverse the io_range_list to find the registered node for @fwnode.
  */
 struct logic_pio_hwaddr *find_io_range_by_fwnode(struct fwnode_handle *fwnode)
 {
 	struct logic_pio_hwaddr *range, *found_range = NULL;

 	rcu_read_lock();
 	list_for_each_entry_rcu(range, &io_range_list, list) {
 		if (range->fwnode == fwnode) {
 			found_range = range;
 			break;
 		}
 	}
 	rcu_read_unlock();

 	return found_range;
 }

 /* Return a registered range given an input PIO token */
 static struct logic_pio_hwaddr *find_io_range(unsigned long pio)
 {
 	struct logic_pio_hwaddr *range, *found_range = NULL;

 	rcu_read_lock();
 	list_for_each_entry_rcu(range, &io_range_list, list) {
 		if (in_range(pio, range->io_start, range->size)) {
 			found_range = range;
 			break;
 		}
 	}
 	rcu_read_unlock();

 	if (!found_range)
 		pr_err("PIO entry token 0x%lx invalid\n", pio);

 	return found_range;
 }

 /**
  * logic_pio_to_hwaddr - translate logical PIO to HW address
  * @pio: logical PIO value
  *
  * Returns HW address if valid, ~0 otherwise.
  *
  * Translate the input logical PIO to the corresponding hardware address.
  * The input PIO should be unique in the whole logical PIO space.
  */
 resource_size_t logic_pio_to_hwaddr(unsigned long pio)
 {
 	struct logic_pio_hwaddr *range;

 	range = find_io_range(pio);
 	if (range)
 		return range->hw_start + pio - range->io_start;

 	return (resource_size_t)~0;
 }

 /**
  * logic_pio_trans_hwaddr - translate HW address to logical PIO
  * @fwnode: FW node reference for the host
  * @addr: Host-relative HW address
  * @size: size to translate
  *
  * Returns Logical PIO value if successful, ~0UL otherwise
  */
 unsigned long logic_pio_trans_hwaddr(struct fwnode_handle *fwnode,
 				     resource_size_t addr, resource_size_t size)
 {
 	struct logic_pio_hwaddr *range;

 	range = find_io_range_by_fwnode(fwnode);
 	if (!range || range->flags == LOGIC_PIO_CPU_MMIO) {
 		pr_err("IO range not found or invalid\n");
 		return ~0UL;
 	}
 	if (range->size < size) {
 		pr_err("resource size %pa cannot fit in IO range size %pa\n",
 		       &size, &range->size);
 		return ~0UL;
 	}
 	return addr - range->hw_start + range->io_start;
 }

 unsigned long logic_pio_trans_cpuaddr(resource_size_t addr)
 {
 	struct logic_pio_hwaddr *range;

 	rcu_read_lock();
 	list_for_each_entry_rcu(range, &io_range_list, list) {
 		if (range->flags != LOGIC_PIO_CPU_MMIO)
 			continue;
 		if (in_range(addr, range->hw_start, range->size)) {
 			unsigned long cpuaddr;

 			cpuaddr = addr - range->hw_start + range->io_start;

 			rcu_read_unlock();
 			return cpuaddr;
 		}
 	}
 	rcu_read_unlock();

 	pr_err("addr %pa not registered in io_range_list\n", &addr);

 	return ~0UL;
 }

 #if defined(CONFIG_INDIRECT_PIO) && defined(PCI_IOBASE)
 #define BUILD_LOGIC_IO(bwl, type)					\
 type logic_in##bwl(unsigned long addr)					\
 {									\
 	type ret = (type)~0;						\
 									\
 	if (addr < MMIO_UPPER_LIMIT) {					\
 		ret = _in##bwl(addr);					\
 	} else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
 		struct logic_pio_hwaddr *entry = find_io_range(addr);	\
 									\
 		if (entry)						\
 			ret = entry->ops->in(entry->hostdata,		\
 					addr, sizeof(type));		\
 		else							\
 			WARN_ON_ONCE(1);				\
 	}								\
 	return ret;							\
 }									\
 									\
 void logic_out##bwl(type value, unsigned long addr)			\
 {									\
 	if (addr < MMIO_UPPER_LIMIT) {					\
 		_out##bwl(value, addr);				\
 	} else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) {	\
 		struct logic_pio_hwaddr *entry = find_io_range(addr);	\
 									\
 		if (entry)						\
 			entry->ops->out(entry->hostdata,		\
 					addr, value, sizeof(type));	\
 		else							\
 			WARN_ON_ONCE(1);				\
 	}								\
 }									\
 									\
 void logic_ins##bwl(unsigned long addr, void *buffer,			\
 		    unsigned int count)					\
 {									\
 	if (addr < MMIO_UPPER_LIMIT) {					\
 		reads##bwl(PCI_IOBASE + addr, buffer, count);		\
 	} else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) {	\
 		struct logic_pio_hwaddr *entry = find_io_range(addr);	\
 									\
 		if (entry)						\
 			entry->ops->ins(entry->hostdata,		\
 				addr, buffer, sizeof(type), count);	\
 		else							\
 			WARN_ON_ONCE(1);				\
 	}								\
 									\
 }									\
 									\
 void logic_outs##bwl(unsigned long addr, const void *buffer,		\
 		     unsigned int count)				\
 {									\
 	if (addr < MMIO_UPPER_LIMIT) {					\
 		writes##bwl(PCI_IOBASE + addr, buffer, count);		\
 	} else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) {	\
 		struct logic_pio_hwaddr *entry = find_io_range(addr);	\
 									\
 		if (entry)						\
 			entry->ops->outs(entry->hostdata,		\
 				addr, buffer, sizeof(type), count);	\
 		else							\
 			WARN_ON_ONCE(1);				\
 	}								\
 }

 BUILD_LOGIC_IO(b, u8)
 EXPORT_SYMBOL(logic_inb);
 EXPORT_SYMBOL(logic_insb);
 EXPORT_SYMBOL(logic_outb);
 EXPORT_SYMBOL(logic_outsb);

 BUILD_LOGIC_IO(w, u16)
 EXPORT_SYMBOL(logic_inw);
 EXPORT_SYMBOL(logic_insw);
 EXPORT_SYMBOL(logic_outw);
 EXPORT_SYMBOL(logic_outsw);

 BUILD_LOGIC_IO(l, u32)
 EXPORT_SYMBOL(logic_inl);
 EXPORT_SYMBOL(logic_insl);
 EXPORT_SYMBOL(logic_outl);
 EXPORT_SYMBOL(logic_outsl);

 #endif /* CONFIG_INDIRECT_PIO && PCI_IOBASE */
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Copyright (C) 2017 HiSilicon Limited, All Rights Reserved.
	* Author: Gabriele Paoloni <gabriele.paoloni@huawei.com>
	* Author: Zhichang Yuan <yuanzhichang@hisilicon.com>
	* Author: John Garry <john.garry@huawei.com>
	*/

	#define pr_fmt(fmt) "LOGIC PIO: " fmt

	#include <linux/of.h>
	#include <linux/io.h>
	#include <linux/logic_pio.h>
	#include <linux/mm.h>
	#include <linux/rculist.h>
	#include <linux/sizes.h>
	#include <linux/slab.h>

	/* The unique hardware address list */
	static LIST_HEAD(io_range_list);
	static DEFINE_MUTEX(io_range_mutex);

	/**
	* logic_pio_register_range - register logical PIO range for a host
	* @new_range: pointer to the IO range to be registered.
	*
	* Returns 0 on success, the error code in case of failure.
	* If the range already exists, -EEXIST will be returned, which should be
	* considered a success.
	*
	* Register a new IO range node in the IO range list.
	*/
	int logic_pio_register_range(struct logic_pio_hwaddr *new_range)
	{
	struct logic_pio_hwaddr *range;
	resource_size_t start;
	resource_size_t end;
	resource_size_t mmio_end = 0;
	resource_size_t iio_sz = MMIO_UPPER_LIMIT;
	int ret = 0;

	if (!new_range \|\| !new_range->fwnode \|\| !new_range->size \|\|
	(new_range->flags == LOGIC_PIO_INDIRECT && !new_range->ops))
	return -EINVAL;

	start = new_range->hw_start;
	end = new_range->hw_start + new_range->size;

	mutex_lock(&io_range_mutex);
	list_for_each_entry(range, &io_range_list, list) {
	if (range->fwnode == new_range->fwnode) {
	/* range already there */
	ret = -EEXIST;
	goto end_register;
	}
	if (range->flags == LOGIC_PIO_CPU_MMIO &&
	new_range->flags == LOGIC_PIO_CPU_MMIO) {
	/* for MMIO ranges we need to check for overlap */
	if (start >= range->hw_start + range->size \|\|
	end < range->hw_start) {
	mmio_end = range->io_start + range->size;
	} else {
	ret = -EFAULT;
	goto end_register;
	}
	} else if (range->flags == LOGIC_PIO_INDIRECT &&
	new_range->flags == LOGIC_PIO_INDIRECT) {
	iio_sz += range->size;
	}
	}

	/* range not registered yet, check for available space */
	if (new_range->flags == LOGIC_PIO_CPU_MMIO) {
	if (mmio_end + new_range->size - 1 > MMIO_UPPER_LIMIT) {
	/* if it's too big check if 64K space can be reserved */
	if (mmio_end + SZ_64K - 1 > MMIO_UPPER_LIMIT) {
	ret = -E2BIG;
	goto end_register;
	}
	new_range->size = SZ_64K;
	pr_warn("Requested IO range too big, new size set to 64K\n");
	}
	new_range->io_start = mmio_end;
	} else if (new_range->flags == LOGIC_PIO_INDIRECT) {
	if (iio_sz + new_range->size - 1 > IO_SPACE_LIMIT) {
	ret = -E2BIG;
	goto end_register;
	}
	new_range->io_start = iio_sz;
	} else {
	/* invalid flag */
	ret = -EINVAL;
	goto end_register;
	}

	list_add_tail_rcu(&new_range->list, &io_range_list);

	end_register:
	mutex_unlock(&io_range_mutex);
	return ret;
	}

	/**
	* logic_pio_unregister_range - unregister a logical PIO range for a host
	* @range: pointer to the IO range which has been already registered.
	*
	* Unregister a previously-registered IO range node.
	*/
	void logic_pio_unregister_range(struct logic_pio_hwaddr *range)
	{
	mutex_lock(&io_range_mutex);
	list_del_rcu(&range->list);
	mutex_unlock(&io_range_mutex);
	synchronize_rcu();
	}

	/**
	* find_io_range_by_fwnode - find logical PIO range for given FW node
	* @fwnode: FW node handle associated with logical PIO range
	*
	* Returns pointer to node on success, NULL otherwise.
	*
	* Traverse the io_range_list to find the registered node for @fwnode.
	*/
	struct logic_pio_hwaddr find_io_range_by_fwnode(struct fwnode_handle fwnode)
	{
	struct logic_pio_hwaddr range, found_range = NULL;

	rcu_read_lock();
	list_for_each_entry_rcu(range, &io_range_list, list) {
	if (range->fwnode == fwnode) {
	found_range = range;
	break;
	}
	}
	rcu_read_unlock();

	return found_range;
	}

	/* Return a registered range given an input PIO token */
	static struct logic_pio_hwaddr *find_io_range(unsigned long pio)
	{
	struct logic_pio_hwaddr range, found_range = NULL;

	rcu_read_lock();
	list_for_each_entry_rcu(range, &io_range_list, list) {
	if (in_range(pio, range->io_start, range->size)) {
	found_range = range;
	break;
	}
	}
	rcu_read_unlock();

	if (!found_range)
	pr_err("PIO entry token 0x%lx invalid\n", pio);

	return found_range;
	}

	/**
	* logic_pio_to_hwaddr - translate logical PIO to HW address
	* @pio: logical PIO value
	*
	* Returns HW address if valid, ~0 otherwise.
	*
	* Translate the input logical PIO to the corresponding hardware address.
	* The input PIO should be unique in the whole logical PIO space.
	*/
	resource_size_t logic_pio_to_hwaddr(unsigned long pio)
	{
	struct logic_pio_hwaddr *range;

	range = find_io_range(pio);
	if (range)
	return range->hw_start + pio - range->io_start;

	return (resource_size_t)~0;
	}

	/**
	* logic_pio_trans_hwaddr - translate HW address to logical PIO
	* @fwnode: FW node reference for the host
	* @addr: Host-relative HW address
	* @size: size to translate
	*
	* Returns Logical PIO value if successful, ~0UL otherwise
	*/
	unsigned long logic_pio_trans_hwaddr(struct fwnode_handle *fwnode,
	resource_size_t addr, resource_size_t size)
	{
	struct logic_pio_hwaddr *range;

	range = find_io_range_by_fwnode(fwnode);
	if (!range \|\| range->flags == LOGIC_PIO_CPU_MMIO) {
	pr_err("IO range not found or invalid\n");
	return ~0UL;
	}
	if (range->size < size) {
	pr_err("resource size %pa cannot fit in IO range size %pa\n",
	&size, &range->size);
	return ~0UL;
	}
	return addr - range->hw_start + range->io_start;
	}

	unsigned long logic_pio_trans_cpuaddr(resource_size_t addr)
	{
	struct logic_pio_hwaddr *range;

	rcu_read_lock();
	list_for_each_entry_rcu(range, &io_range_list, list) {
	if (range->flags != LOGIC_PIO_CPU_MMIO)
	continue;
	if (in_range(addr, range->hw_start, range->size)) {
	unsigned long cpuaddr;

	cpuaddr = addr - range->hw_start + range->io_start;

	rcu_read_unlock();
	return cpuaddr;
	}
	}
	rcu_read_unlock();

	pr_err("addr %pa not registered in io_range_list\n", &addr);

	return ~0UL;
	}

	#if defined(CONFIG_INDIRECT_PIO) && defined(PCI_IOBASE)
	#define BUILD_LOGIC_IO(bwl, type) \
	type logic_in##bwl(unsigned long addr) \
	{ \
	type ret = (type)~0; \
	\
	if (addr < MMIO_UPPER_LIMIT) { \
	ret = _in##bwl(addr); \
	} else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
	struct logic_pio_hwaddr *entry = find_io_range(addr); \
	\
	if (entry) \
	ret = entry->ops->in(entry->hostdata, \
	addr, sizeof(type)); \
	else \
	WARN_ON_ONCE(1); \
	} \
	return ret; \
	} \
	\
	void logic_out##bwl(type value, unsigned long addr) \
	{ \
	if (addr < MMIO_UPPER_LIMIT) { \
	_out##bwl(value, addr); \
	} else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
	struct logic_pio_hwaddr *entry = find_io_range(addr); \
	\
	if (entry) \
	entry->ops->out(entry->hostdata, \
	addr, value, sizeof(type)); \
	else \
	WARN_ON_ONCE(1); \
	} \
	} \
	\
	void logic_ins##bwl(unsigned long addr, void *buffer, \
	unsigned int count) \
	{ \
	if (addr < MMIO_UPPER_LIMIT) { \
	reads##bwl(PCI_IOBASE + addr, buffer, count); \
	} else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
	struct logic_pio_hwaddr *entry = find_io_range(addr); \
	\
	if (entry) \
	entry->ops->ins(entry->hostdata, \
	addr, buffer, sizeof(type), count); \
	else \
	WARN_ON_ONCE(1); \
	} \
	\
	} \
	\
	void logic_outs##bwl(unsigned long addr, const void *buffer, \
	unsigned int count) \
	{ \
	if (addr < MMIO_UPPER_LIMIT) { \
	writes##bwl(PCI_IOBASE + addr, buffer, count); \
	} else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
	struct logic_pio_hwaddr *entry = find_io_range(addr); \
	\
	if (entry) \
	entry->ops->outs(entry->hostdata, \
	addr, buffer, sizeof(type), count); \
	else \
	WARN_ON_ONCE(1); \
	} \
	}

	BUILD_LOGIC_IO(b, u8)
	EXPORT_SYMBOL(logic_inb);
	EXPORT_SYMBOL(logic_insb);
	EXPORT_SYMBOL(logic_outb);
	EXPORT_SYMBOL(logic_outsb);

	BUILD_LOGIC_IO(w, u16)
	EXPORT_SYMBOL(logic_inw);
	EXPORT_SYMBOL(logic_insw);
	EXPORT_SYMBOL(logic_outw);
	EXPORT_SYMBOL(logic_outsw);

	BUILD_LOGIC_IO(l, u32)
	EXPORT_SYMBOL(logic_inl);
	EXPORT_SYMBOL(logic_insl);
	EXPORT_SYMBOL(logic_outl);
	EXPORT_SYMBOL(logic_outsl);

	#endif /* CONFIG_INDIRECT_PIO && PCI_IOBASE */