/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Based on arch/arm/include/asm/io.h
 *
 * Copyright (C) 1996-2000 Russell King
 * Copyright (C) 2012 ARM Ltd.
 */
#ifndef __ASM_IO_H
#define __ASM_IO_H

#include <linux/types.h>
#include <linux/pgtable.h>

#include <asm/byteorder.h>
#include <asm/barrier.h>
#include <asm/memory.h>
#include <asm/early_ioremap.h>
#include <asm/alternative.h>
#include <asm/cpufeature.h>
#include <asm/rsi.h>

/*
 * Generic IO read/write.  These perform native-endian accesses.
 */
#define __raw_writeb __raw_writeb
static __always_inline void __raw_writeb(u8 val, volatile void __iomem *addr)
{
        volatile u8 __iomem *ptr = addr;
        asm volatile("strb %w0, %1" : : "rZ" (val), "Qo" (*ptr));
}

#define __raw_writew __raw_writew
static __always_inline void __raw_writew(u16 val, volatile void __iomem *addr)
{
        volatile u16 __iomem *ptr = addr;
        asm volatile("strh %w0, %1" : : "rZ" (val), "Qo" (*ptr));
}

#define __raw_writel __raw_writel
static __always_inline void __raw_writel(u32 val, volatile void __iomem *addr)
{
        volatile u32 __iomem *ptr = addr;
        asm volatile("str %w0, %1" : : "rZ" (val), "Qo" (*ptr));
}

#define __raw_writeq __raw_writeq
static __always_inline void __raw_writeq(u64 val, volatile void __iomem *addr)
{
        volatile u64 __iomem *ptr = addr;
        asm volatile("str %x0, %1" : : "rZ" (val), "Qo" (*ptr));
}

#define __raw_readb __raw_readb
static __always_inline u8 __raw_readb(const volatile void __iomem *addr)
{
        u8 val;
        asm volatile(ALTERNATIVE("ldrb %w0, [%1]",
                                 "ldarb %w0, [%1]",
                                 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
                     : "=r" (val) : "r" (addr));
        return val;
}

#define __raw_readw __raw_readw
static __always_inline u16 __raw_readw(const volatile void __iomem *addr)
{
        u16 val;

        asm volatile(ALTERNATIVE("ldrh %w0, [%1]",
                                 "ldarh %w0, [%1]",
                                 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
                     : "=r" (val) : "r" (addr));
        return val;
}

#define __raw_readl __raw_readl
static __always_inline u32 __raw_readl(const volatile void __iomem *addr)
{
        u32 val;
        asm volatile(ALTERNATIVE("ldr %w0, [%1]",
                                 "ldar %w0, [%1]",
                                 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
                     : "=r" (val) : "r" (addr));
        return val;
}

#define __raw_readq __raw_readq
static __always_inline u64 __raw_readq(const volatile void __iomem *addr)
{
        u64 val;
        asm volatile(ALTERNATIVE("ldr %0, [%1]",
                                 "ldar %0, [%1]",
                                 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
                     : "=r" (val) : "r" (addr));
        return val;
}

/* IO barriers */
#define __io_ar(v)                                                      \
({                                                                      \
        unsigned long tmp;                                              \
                                                                        \
        dma_rmb();                                                              \
                                                                        \
        /*                                                              \
         * Create a dummy control dependency from the IO read to any    \
         * later instructions. This ensures that a subsequent call to   \
         * udelay() will be ordered due to the ISB in get_cycles().     \
         */                                                             \
        asm volatile("eor       %0, %1, %1\n"                           \
                     "cbnz      %0, ."                                  \
                     : "=r" (tmp) : "r" ((unsigned long)(v))            \
                     : "memory");                                       \
})

#define __io_bw()               dma_wmb()
#define __io_br(v)
#define __io_aw(v)

/* arm64-specific, don't use in portable drivers */
#define __iormb(v)              __io_ar(v)
#define __iowmb()               __io_bw()
#define __iomb()                dma_mb()

/*
 *  I/O port access primitives.
 */
#define arch_has_dev_port()     (1)
#define IO_SPACE_LIMIT          (PCI_IO_SIZE - 1)
#define PCI_IOBASE              ((void __iomem *)PCI_IO_START)

/*
 * The ARM64 iowrite implementation is intended to support drivers that want to
 * use write combining. For instance PCI drivers using write combining with a 64
 * byte __iowrite64_copy() expect to get a 64 byte MemWr TLP on the PCIe bus.
 *
 * Newer ARM core have sensitive write combining buffers, it is important that
 * the stores be contiguous blocks of store instructions. Normal memcpy
 * approaches have a very low chance to generate write combining.
 *
 * Since this is the only API on ARM64 that should be used with write combining
 * it also integrates the DGH hint which is supposed to lower the latency to
 * emit the large TLP from the CPU.
 */

static __always_inline void
__const_memcpy_toio_aligned32(volatile u32 __iomem *to, const u32 *from,
                              size_t count)
{
        switch (count) {
        case 8:
                asm volatile("str %w0, [%8, #4 * 0]\n"
                             "str %w1, [%8, #4 * 1]\n"
                             "str %w2, [%8, #4 * 2]\n"
                             "str %w3, [%8, #4 * 3]\n"
                             "str %w4, [%8, #4 * 4]\n"
                             "str %w5, [%8, #4 * 5]\n"
                             "str %w6, [%8, #4 * 6]\n"
                             "str %w7, [%8, #4 * 7]\n"
                             :
                             : "rZ"(from[0]), "rZ"(from[1]), "rZ"(from[2]),
                               "rZ"(from[3]), "rZ"(from[4]), "rZ"(from[5]),
                               "rZ"(from[6]), "rZ"(from[7]), "r"(to));
                break;
        case 4:
                asm volatile("str %w0, [%4, #4 * 0]\n"
                             "str %w1, [%4, #4 * 1]\n"
                             "str %w2, [%4, #4 * 2]\n"
                             "str %w3, [%4, #4 * 3]\n"
                             :
                             : "rZ"(from[0]), "rZ"(from[1]), "rZ"(from[2]),
                               "rZ"(from[3]), "r"(to));
                break;
        case 2:
                asm volatile("str %w0, [%2, #4 * 0]\n"
                             "str %w1, [%2, #4 * 1]\n"
                             :
                             : "rZ"(from[0]), "rZ"(from[1]), "r"(to));
                break;
        case 1:
                __raw_writel(*from, to);
                break;
        default:
                BUILD_BUG();
        }
}

void __iowrite32_copy_full(void __iomem *to, const void *from, size_t count);

static __always_inline void
__iowrite32_copy(void __iomem *to, const void *from, size_t count)
{
        if (__builtin_constant_p(count) &&
            (count == 8 || count == 4 || count == 2 || count == 1)) {
                __const_memcpy_toio_aligned32(to, from, count);
                dgh();
        } else {
                __iowrite32_copy_full(to, from, count);
        }
}
#define __iowrite32_copy __iowrite32_copy

static __always_inline void
__const_memcpy_toio_aligned64(volatile u64 __iomem *to, const u64 *from,
                              size_t count)
{
        switch (count) {
        case 8:
                asm volatile("str %x0, [%8, #8 * 0]\n"
                             "str %x1, [%8, #8 * 1]\n"
                             "str %x2, [%8, #8 * 2]\n"
                             "str %x3, [%8, #8 * 3]\n"
                             "str %x4, [%8, #8 * 4]\n"
                             "str %x5, [%8, #8 * 5]\n"
                             "str %x6, [%8, #8 * 6]\n"
                             "str %x7, [%8, #8 * 7]\n"
                             :
                             : "rZ"(from[0]), "rZ"(from[1]), "rZ"(from[2]),
                               "rZ"(from[3]), "rZ"(from[4]), "rZ"(from[5]),
                               "rZ"(from[6]), "rZ"(from[7]), "r"(to));
                break;
        case 4:
                asm volatile("str %x0, [%4, #8 * 0]\n"
                             "str %x1, [%4, #8 * 1]\n"
                             "str %x2, [%4, #8 * 2]\n"
                             "str %x3, [%4, #8 * 3]\n"
                             :
                             : "rZ"(from[0]), "rZ"(from[1]), "rZ"(from[2]),
                               "rZ"(from[3]), "r"(to));
                break;
        case 2:
                asm volatile("str %x0, [%2, #8 * 0]\n"
                             "str %x1, [%2, #8 * 1]\n"
                             :
                             : "rZ"(from[0]), "rZ"(from[1]), "r"(to));
                break;
        case 1:
                __raw_writeq(*from, to);
                break;
        default:
                BUILD_BUG();
        }
}

void __iowrite64_copy_full(void __iomem *to, const void *from, size_t count);

static __always_inline void
__iowrite64_copy(void __iomem *to, const void *from, size_t count)
{
        if (__builtin_constant_p(count) &&
            (count == 8 || count == 4 || count == 2 || count == 1)) {
                __const_memcpy_toio_aligned64(to, from, count);
                dgh();
        } else {
                __iowrite64_copy_full(to, from, count);
        }
}
#define __iowrite64_copy __iowrite64_copy

/*
 * I/O memory mapping functions.
 */

typedef int (*ioremap_prot_hook_t)(phys_addr_t phys_addr, size_t size,
                                   pgprot_t *prot);
int arm64_ioremap_prot_hook_register(const ioremap_prot_hook_t hook);
void __iomem *__ioremap_prot(phys_addr_t phys, size_t size, pgprot_t prot);

static inline void __iomem *ioremap_prot(phys_addr_t phys, size_t size,
                                         pgprot_t user_prot)
{
        pgprot_t prot;
        ptdesc_t user_prot_val = pgprot_val(user_prot);

        if (WARN_ON_ONCE(!(user_prot_val & PTE_USER)))
                return NULL;

        prot = __pgprot_modify(PAGE_KERNEL, PTE_ATTRINDX_MASK,
                               user_prot_val & PTE_ATTRINDX_MASK);
        return __ioremap_prot(phys, size, prot);
}
#define ioremap_prot ioremap_prot

#define ioremap(addr, size)     \
        __ioremap_prot((addr), (size), __pgprot(PROT_DEVICE_nGnRE))
#define ioremap_wc(addr, size)  \
        __ioremap_prot((addr), (size), __pgprot(PROT_NORMAL_NC))
#define ioremap_np(addr, size)  \
        __ioremap_prot((addr), (size), __pgprot(PROT_DEVICE_nGnRnE))


#define ioremap_encrypted(addr, size)   \
        __ioremap_prot((addr), (size), PAGE_KERNEL)

/*
 * io{read,write}{16,32,64}be() macros
 */
#define ioread16be(p)           ({ __u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(__v); __v; })
#define ioread32be(p)           ({ __u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(__v); __v; })
#define ioread64be(p)           ({ __u64 __v = be64_to_cpu((__force __be64)__raw_readq(p)); __iormb(__v); __v; })

#define iowrite16be(v,p)        ({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
#define iowrite32be(v,p)        ({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
#define iowrite64be(v,p)        ({ __iowmb(); __raw_writeq((__force __u64)cpu_to_be64(v), p); })

#include <asm-generic/io.h>

#define ioremap_cache ioremap_cache
static inline void __iomem *ioremap_cache(phys_addr_t addr, size_t size)
{
        if (pfn_is_map_memory(__phys_to_pfn(addr)))
                return (void __iomem *)__phys_to_virt(addr);

        return __ioremap_prot(addr, size, __pgprot(PROT_NORMAL));
}

/*
 * More restrictive address range checking than the default implementation
 * (PHYS_OFFSET and PHYS_MASK taken into account).
 */
#define ARCH_HAS_VALID_PHYS_ADDR_RANGE
extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);

extern bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
                                        unsigned long flags);
#define arch_memremap_can_ram_remap arch_memremap_can_ram_remap

static inline bool arm64_is_protected_mmio(phys_addr_t phys_addr, size_t size)
{
        if (unlikely(is_realm_world()))
                return arm64_rsi_is_protected(phys_addr, size);
        return false;
}

#endif  /* __ASM_IO_H */