diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Kconfig | 16 | ||||
| -rw-r--r-- | lib/Makefile | 2 | ||||
| -rw-r--r-- | lib/logic_pio.c | 280 |
3 files changed, 298 insertions, 0 deletions
diff --git a/lib/Kconfig b/lib/Kconfig index e960894..5fe5776 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -55,6 +55,22 @@ config ARCH_USE_CMPXCHG_LOCKREF config ARCH_HAS_FAST_MULTIPLIER bool +config INDIRECT_PIO + bool "Access I/O in non-MMIO mode" + depends on ARM64 + help + On some platforms where no separate I/O space exists, there are I/O + hosts which can not be accessed in MMIO mode. Using the logical PIO + mechanism, the host-local I/O resource can be mapped into system + logic PIO space shared with MMIO hosts, such as PCI/PCIe, then the + system can access the I/O devices with the mapped-logic PIO through + I/O accessors. + + This way has relatively little I/O performance cost. Please make + sure your devices really need this configure item enabled. + + When in doubt, say N. + config CRC_CCITT tristate "CRC-CCITT functions" help diff --git a/lib/Makefile b/lib/Makefile index 0bd50d71f..8fc0d3a 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -82,6 +82,8 @@ obj-$(CONFIG_HAS_IOMEM) += iomap_copy.o devres.o obj-$(CONFIG_CHECK_SIGNATURE) += check_signature.o obj-$(CONFIG_DEBUG_LOCKING_API_SELFTESTS) += locking-selftest.o +obj-y += logic_pio.o + obj-$(CONFIG_GENERIC_HWEIGHT) += hweight.o obj-$(CONFIG_BTREE) += btree.o diff --git a/lib/logic_pio.c b/lib/logic_pio.c new file mode 100644 index 0000000..feea48f --- /dev/null +++ b/lib/logic_pio.c @@ -0,0 +1,280 @@ +// 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_sz = 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_rcu(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_sz += 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_sz + new_range->size - 1 > MMIO_UPPER_LIMIT) { + /* if it's too big check if 64K space can be reserved */ + if (mmio_sz + 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_sz; + } 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; + + list_for_each_entry_rcu(range, &io_range_list, list) { + if (range->fwnode == fwnode) + return range; + } + return NULL; +} + +/* 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; + + list_for_each_entry_rcu(range, &io_range_list, list) { + if (in_range(pio, range->io_start, range->size)) + return range; + } + pr_err("PIO entry token %lx invalid\n", pio); + return NULL; +} + +/** + * 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; + + 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)) + return addr - range->hw_start + range->io_start; + } + pr_err("addr %llx not registered in io_range_list\n", + (unsigned long long) 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 */ |
