// 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>
*/
#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);
/* Consider a kernel general helper for this */
#define in_range(b, first, len) ((b) >= (first) && (b) < (first) + (len))
/**
* 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.
*
* 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)
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 */
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;
}
/**
* 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(bw, type) \
type logic_in##bw(unsigned long addr) \
{ \
type ret = (type)~0; \
\
if (addr < MMIO_UPPER_LIMIT) { \
ret = read##bw(PCI_IOBASE + addr); \
} else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
struct logic_pio_hwaddr *entry = find_io_range(addr); \
\
if (entry && entry->ops) \
ret = entry->ops->in(entry->hostdata, \
addr, sizeof(type)); \
else \
WARN_ON_ONCE(1); \
} \
return ret; \
} \
\
void logic_out##bw(type value, unsigned long addr) \
{ \
if (addr < MMIO_UPPER_LIMIT) { \
write##bw(value, PCI_IOBASE + addr); \
} else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
struct logic_pio_hwaddr *entry = find_io_range(addr); \
\
if (entry && entry->ops) \
entry->ops->out(entry->hostdata, \
addr, value, sizeof(type)); \
else \
WARN_ON_ONCE(1); \
} \
} \
\
void logic_ins##bw(unsigned long addr, void *buffer, \
unsigned int count) \
{ \
if (addr < MMIO_UPPER_LIMIT) { \
reads##bw(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) \
entry->ops->ins(entry->hostdata, \
addr, buffer, sizeof(type), count); \
else \
WARN_ON_ONCE(1); \
} \
\
} \
\
void logic_outs##bw(unsigned long addr, const void *buffer, \
unsigned int count) \
{ \
if (addr < MMIO_UPPER_LIMIT) { \
writes##bw(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) \
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 */
