// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (c) 2011 The Chromium OS Authors.
 */

#include <common.h>
#include <bootstage.h>
#include <cpu_func.h>
#include <errno.h>
#include <log.h>
#include <asm/global_data.h>
#include <linux/delay.h>
#include <linux/libfdt.h>
#include <os.h>
#include <asm/io.h>
#include <asm/malloc.h>
#include <asm/setjmp.h>
#include <asm/state.h>

DECLARE_GLOBAL_DATA_PTR;

/* Enable access to PCI memory with map_sysmem() */
static bool enable_pci_map;

#ifdef CONFIG_PCI
/* Last device that was mapped into memory, and length of mapping */
static struct udevice *map_dev;
unsigned long map_len;
#endif

void sandbox_exit(void)
{
        /* Do this here while it still has an effect */
        os_fd_restore();

        if (state_uninit())
                os_exit(2);

        /* This is considered normal termination for now */
        os_exit(0);
}

/* delay x useconds */
void __udelay(unsigned long usec)
{
        struct sandbox_state *state = state_get_current();

        if (!state->skip_delays)
                os_usleep(usec);
}

int cleanup_before_linux(void)
{
        return 0;
}

int cleanup_before_linux_select(int flags)
{
        return 0;
}

/**
 * is_in_sandbox_mem() - Checks if a pointer is within sandbox's emulated DRAM
 *
 * This provides a way to check if a pointer is owned by sandbox (and is within
 * its RAM) or not. Sometimes pointers come from a test which conceptually runs
 * output sandbox, potentially with direct access to the C-library malloc()
 * function, or the sandbox stack (which is not actually within the emulated
 * DRAM.
 *
 * Such pointers obviously cannot be mapped into sandbox's DRAM, so we must
 * detect them an process them separately, by recording a mapping to a tag,
 * which we can use to map back to the pointer later.
 *
 * @ptr: Pointer to check
 * @return true if this is within sandbox emulated DRAM, false if not
 */
static bool is_in_sandbox_mem(const void *ptr)
{
        return (const uint8_t *)ptr >= gd->arch.ram_buf &&
                (const uint8_t *)ptr < gd->arch.ram_buf + gd->ram_size;
}

/**
 * phys_to_virt() - Converts a sandbox RAM address to a pointer
 *
 * Sandbox uses U-Boot addresses from 0 to the size of DRAM. These index into
 * the emulated DRAM buffer used by sandbox. This function converts such an
 * address to a pointer into this buffer, which can be used to access the
 * memory.
 *
 * If the address is outside this range, it is assumed to be a tag
 */
void *phys_to_virt(phys_addr_t paddr)
{
        struct sandbox_mapmem_entry *mentry;
        struct sandbox_state *state;

        /* If the address is within emulated DRAM, calculate the value */
        if (paddr < gd->ram_size)
                return (void *)(gd->arch.ram_buf + paddr);

        /*
         * Otherwise search out list of tags for the correct pointer previously
         * created by map_to_sysmem()
         */
        state = state_get_current();
        list_for_each_entry(mentry, &state->mapmem_head, sibling_node) {
                if (mentry->tag == paddr) {
                        debug("%s: Used map from %lx to %p\n", __func__,
                              (ulong)paddr, mentry->ptr);
                        return mentry->ptr;
                }
        }

        printf("%s: Cannot map sandbox address %lx (SDRAM from 0 to %lx)\n",
               __func__, (ulong)paddr, (ulong)gd->ram_size);
        os_abort();

        /* Not reached */
        return NULL;
}

struct sandbox_mapmem_entry *find_tag(const void *ptr)
{
        struct sandbox_mapmem_entry *mentry;
        struct sandbox_state *state = state_get_current();

        list_for_each_entry(mentry, &state->mapmem_head, sibling_node) {
                if (mentry->ptr == ptr) {
                        debug("%s: Used map from %p to %lx\n", __func__, ptr,
                              mentry->tag);
                        return mentry;
                }
        }
        return NULL;
}

phys_addr_t virt_to_phys(void *ptr)
{
        struct sandbox_mapmem_entry *mentry;

        /*
         * If it is in emulated RAM, don't bother looking for a tag. Just
         * calculate the pointer using the provides offset into the RAM buffer.
         */
        if (is_in_sandbox_mem(ptr))
                return (phys_addr_t)((uint8_t *)ptr - gd->arch.ram_buf);

        mentry = find_tag(ptr);
        if (!mentry) {
                /* Abort so that gdb can be used here */
                printf("%s: Cannot map sandbox address %p (SDRAM from 0 to %lx)\n",
                       __func__, ptr, (ulong)gd->ram_size);
                os_abort();
        }
        debug("%s: Used map from %p to %lx\n", __func__, ptr, mentry->tag);

        return mentry->tag;
}

void *map_physmem(phys_addr_t paddr, unsigned long len, unsigned long flags)
{
#if defined(CONFIG_PCI) && !defined(CONFIG_SPL_BUILD)
        unsigned long plen = len;
        void *ptr;

        map_dev = NULL;
        if (enable_pci_map && !pci_map_physmem(paddr, &len, &map_dev, &ptr)) {
                if (plen != len) {
                        printf("%s: Warning: partial map at %x, wanted %lx, got %lx\n",
                               __func__, (uint)paddr, len, plen);
                }
                map_len = len;
                return ptr;
        }
#endif

        return phys_to_virt(paddr);
}

void unmap_physmem(const void *ptr, unsigned long flags)
{
#ifdef CONFIG_PCI
        if (map_dev) {
                pci_unmap_physmem(ptr, map_len, map_dev);
                map_dev = NULL;
        }
#endif
}

phys_addr_t map_to_sysmem(const void *ptr)
{
        struct sandbox_mapmem_entry *mentry;

        /*
         * If it is in emulated RAM, don't bother creating a tag. Just return
         * the offset into the RAM buffer.
         */
        if (is_in_sandbox_mem(ptr))
                return (u8 *)ptr - gd->arch.ram_buf;

        /*
         * See if there is an existing tag with this pointer. If not, set up a
         * new one.
         */
        mentry = find_tag(ptr);
        if (!mentry) {
                struct sandbox_state *state = state_get_current();

                mentry = malloc(sizeof(*mentry));
                if (!mentry) {
                        printf("%s: Error: Out of memory\n", __func__);
                        os_exit(ENOMEM);
                }
                mentry->tag = state->next_tag++;
                mentry->ptr = (void *)ptr;
                list_add_tail(&mentry->sibling_node, &state->mapmem_head);
                debug("%s: Added map from %p to %lx\n", __func__, ptr,
                      (ulong)mentry->tag);
        }

        /*
         * Return the tag as the address to use. A later call to map_sysmem()
         * will return ptr
         */
        return mentry->tag;
}

unsigned int sandbox_read(const void *addr, enum sandboxio_size_t size)
{
        struct sandbox_state *state = state_get_current();

        if (!state->allow_memio)
                return 0;

        switch (size) {
        case SB_SIZE_8:
                return *(u8 *)addr;
        case SB_SIZE_16:
                return *(u16 *)addr;
        case SB_SIZE_32:
                return *(u32 *)addr;
        case SB_SIZE_64:
                return *(u64 *)addr;
        }

        return 0;
}

void sandbox_write(void *addr, unsigned int val, enum sandboxio_size_t size)
{
        struct sandbox_state *state = state_get_current();

        if (!state->allow_memio)
                return;

        switch (size) {
        case SB_SIZE_8:
                *(u8 *)addr = val;
                break;
        case SB_SIZE_16:
                *(u16 *)addr = val;
                break;
        case SB_SIZE_32:
                *(u32 *)addr = val;
                break;
        case SB_SIZE_64:
                *(u64 *)addr = val;
                break;
        }
}

void sandbox_set_enable_memio(bool enable)
{
        struct sandbox_state *state = state_get_current();

        state->allow_memio = enable;
}

void sandbox_set_enable_pci_map(int enable)
{
        enable_pci_map = enable;
}

void flush_dcache_range(unsigned long start, unsigned long stop)
{
}

void invalidate_dcache_range(unsigned long start, unsigned long stop)
{
}

void *board_fdt_blob_setup(int *ret)
{
        struct sandbox_state *state = state_get_current();
        const char *fname = state->fdt_fname;
        void *blob = NULL;
        loff_t size;
        int err;
        int fd;

        blob = map_sysmem(CONFIG_SYS_FDT_LOAD_ADDR, 0);
        *ret = 0;
        if (!state->fdt_fname) {
                err = fdt_create_empty_tree(blob, 256);
                if (!err)
                        goto done;
                printf("Unable to create empty FDT: %s\n", fdt_strerror(err));
                *ret = -EINVAL;
                goto fail;
        }

        err = os_get_filesize(fname, &size);
        if (err < 0) {
                printf("Failed to find FDT file '%s'\n", fname);
                *ret = err;
                goto fail;
        }
        fd = os_open(fname, OS_O_RDONLY);
        if (fd < 0) {
                printf("Failed to open FDT file '%s'\n", fname);
                *ret = -EACCES;
                goto fail;
        }

        if (os_read(fd, blob, size) != size) {
                os_close(fd);
                printf("Failed to read FDT file '%s'\n", fname);
                *ret =  -EIO;
                goto fail;
        }
        os_close(fd);

done:
        return blob;
fail:
        return NULL;
}

ulong timer_get_boot_us(void)
{
        static uint64_t base_count;
        uint64_t count = os_get_nsec();

        if (!base_count)
                base_count = count;

        return (count - base_count) / 1000;
}