// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2007 Lemote, Inc. & Institute of Computing Technology
 * Author: Fuxin Zhang, zhangfx@lemote.com
 */
#include <linux/pci.h>

#include <pci.h>
#include <loongson.h>

static struct resource loongson_pci_mem_resource = {
        .name   = "pci memory space",
        .start  = LOONGSON_PCI_MEM_START,
        .end    = LOONGSON_PCI_MEM_END,
        .flags  = IORESOURCE_MEM,
};

static struct resource loongson_pci_io_resource = {
        .name   = "pci io space",
        .start  = 0x00000000UL, /* See loongson2ef_pcibios_init(). */
        .end    = IO_SPACE_LIMIT,
        .flags  = IORESOURCE_IO,
};

static struct pci_controller  loongson_pci_controller = {
        .pci_ops        = &loongson_pci_ops,
        .io_resource    = &loongson_pci_io_resource,
        .mem_resource   = &loongson_pci_mem_resource,
        .mem_offset     = 0x00000000UL,
        .io_offset      = 0x00000000UL,
};

static void __init setup_pcimap(void)
{
        /*
         * local to PCI mapping for CPU accessing PCI space
         * CPU address space [256M,448M] is window for accessing pci space
         * we set pcimap_lo[0,1,2] to map it to pci space[0M,64M], [320M,448M]
         *
         * pcimap: PCI_MAP2  PCI_Mem_Lo2 PCI_Mem_Lo1 PCI_Mem_Lo0
         *           [<2G]   [384M,448M] [320M,384M] [0M,64M]
         */
        LOONGSON_PCIMAP = LOONGSON_PCIMAP_PCIMAP_2 |
                LOONGSON_PCIMAP_WIN(2, LOONGSON_PCILO2_BASE) |
                LOONGSON_PCIMAP_WIN(1, LOONGSON_PCILO1_BASE) |
                LOONGSON_PCIMAP_WIN(0, 0);

        /*
         * PCI-DMA to local mapping: [2G,2G+256M] -> [0M,256M]
         */
        LOONGSON_PCIBASE0 = 0x80000000ul;   /* base: 2G -> mmap: 0M */
        /* size: 256M, burst transmission, pre-fetch enable, 64bit */
        LOONGSON_PCI_HIT0_SEL_L = 0xc000000cul;
        LOONGSON_PCI_HIT0_SEL_H = 0xfffffffful;
        LOONGSON_PCI_HIT1_SEL_L = 0x00000006ul; /* set this BAR as invalid */
        LOONGSON_PCI_HIT1_SEL_H = 0x00000000ul;
        LOONGSON_PCI_HIT2_SEL_L = 0x00000006ul; /* set this BAR as invalid */
        LOONGSON_PCI_HIT2_SEL_H = 0x00000000ul;

        /* avoid deadlock of PCI reading/writing lock operation */
        LOONGSON_PCI_ISR4C = 0xd2000001ul;

        /* can not change gnt to break pci transfer when device's gnt not
        deassert for some broken device */
        LOONGSON_PXARB_CFG = 0x00fe0105ul;

#ifdef CONFIG_CPU_SUPPORTS_ADDRWINCFG
        /*
         * set cpu addr window2 to map CPU address space to PCI address space
         */
        LOONGSON_ADDRWIN_CPUTOPCI(ADDRWIN_WIN2, LOONGSON_CPU_MEM_SRC,
                LOONGSON_PCI_MEM_DST, MMAP_CPUTOPCI_SIZE);
#endif
}

void __init loongson2ef_pcibios_init(void)
{
        setup_pcimap();

        /*
         * ISA-mode only IDE controllers have a hard dependency on ISA IO ports.
         *
         * Claim them by setting PCI IO space to start at 0x00000000, and set
         * PCIBIOS_MIN_IO to prevent non-legacy PCI devices from touching
         * reserved regions.
         */
        PCIBIOS_MIN_IO = LOONGSON_PCI_IO_START;

        loongson_pci_controller.io_map_base = mips_io_port_base;
        register_pci_controller(&loongson_pci_controller);
}