/*
 *  linux/arch/arm/kernel/bios32.c
 *
 *  PCI bios-type initialisation for PCI machines
 *
 *  Bits taken from various places.
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/io.h>

#include <asm/mach-types.h>
#include <asm/mach/pci.h>

static int debug_pci;
static int use_firmware;

/*
 * We can't use pci_find_device() here since we are
 * called from interrupt context.
 */
static void pcibios_bus_report_status(struct pci_bus *bus, u_int status_mask, int warn)
{
        struct pci_dev *dev;

        list_for_each_entry(dev, &bus->devices, bus_list) {
                u16 status;

                /*
                 * ignore host bridge - we handle
                 * that separately
                 */
                if (dev->bus->number == 0 && dev->devfn == 0)
                        continue;

                pci_read_config_word(dev, PCI_STATUS, &status);
                if (status == 0xffff)
                        continue;

                if ((status & status_mask) == 0)
                        continue;

                /* clear the status errors */
                pci_write_config_word(dev, PCI_STATUS, status & status_mask);

                if (warn)
                        printk("(%s: %04X) ", pci_name(dev), status);
        }

        list_for_each_entry(dev, &bus->devices, bus_list)
                if (dev->subordinate)
                        pcibios_bus_report_status(dev->subordinate, status_mask, warn);
}

void pcibios_report_status(u_int status_mask, int warn)
{
        struct list_head *l;

        list_for_each(l, &pci_root_buses) {
                struct pci_bus *bus = pci_bus_b(l);

                pcibios_bus_report_status(bus, status_mask, warn);
        }
}

/*
 * We don't use this to fix the device, but initialisation of it.
 * It's not the correct use for this, but it works.
 * Note that the arbiter/ISA bridge appears to be buggy, specifically in
 * the following area:
 * 1. park on CPU
 * 2. ISA bridge ping-pong
 * 3. ISA bridge master handling of target RETRY
 *
 * Bug 3 is responsible for the sound DMA grinding to a halt.  We now
 * live with bug 2.
 */
static void __devinit pci_fixup_83c553(struct pci_dev *dev)
{
        /*
         * Set memory region to start at address 0, and enable IO
         */
        pci_write_config_dword(dev, PCI_BASE_ADDRESS_0, PCI_BASE_ADDRESS_SPACE_MEMORY);
        pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_IO);

        dev->resource[0].end -= dev->resource[0].start;
        dev->resource[0].start = 0;

        /*
         * All memory requests from ISA to be channelled to PCI
         */
        pci_write_config_byte(dev, 0x48, 0xff);

        /*
         * Enable ping-pong on bus master to ISA bridge transactions.
         * This improves the sound DMA substantially.  The fixed
         * priority arbiter also helps (see below).
         */
        pci_write_config_byte(dev, 0x42, 0x01);

        /*
         * Enable PCI retry
         */
        pci_write_config_byte(dev, 0x40, 0x22);

        /*
         * We used to set the arbiter to "park on last master" (bit
         * 1 set), but unfortunately the CyberPro does not park the
         * bus.  We must therefore park on CPU.  Unfortunately, this
         * may trigger yet another bug in the 553.
         */
        pci_write_config_byte(dev, 0x83, 0x02);

        /*
         * Make the ISA DMA request lowest priority, and disable
         * rotating priorities completely.
         */
        pci_write_config_byte(dev, 0x80, 0x11);
        pci_write_config_byte(dev, 0x81, 0x00);

        /*
         * Route INTA input to IRQ 11, and set IRQ11 to be level
         * sensitive.
         */
        pci_write_config_word(dev, 0x44, 0xb000);
        outb(0x08, 0x4d1);
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_WINBOND, PCI_DEVICE_ID_WINBOND_83C553, pci_fixup_83c553);

static void __devinit pci_fixup_unassign(struct pci_dev *dev)
{
        dev->resource[0].end -= dev->resource[0].start;
        dev->resource[0].start = 0;
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_WINBOND2, PCI_DEVICE_ID_WINBOND2_89C940F, pci_fixup_unassign);

/*
 * Prevent the PCI layer from seeing the resources allocated to this device
 * if it is the host bridge by marking it as such.  These resources are of
 * no consequence to the PCI layer (they are handled elsewhere).
 */
static void __devinit pci_fixup_dec21285(struct pci_dev *dev)
{
        int i;

        if (dev->devfn == 0) {
                dev->class &= 0xff;
                dev->class |= PCI_CLASS_BRIDGE_HOST << 8;
                for (i = 0; i < PCI_NUM_RESOURCES; i++) {
                        dev->resource[i].start = 0;
                        dev->resource[i].end   = 0;
                        dev->resource[i].flags = 0;
                }
        }
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_DEC, PCI_DEVICE_ID_DEC_21285, pci_fixup_dec21285);

/*
 * Same as above. The PrPMC800 carrier board for the PrPMC1100 
 * card maps the host-bridge @ 00:01:00 for some reason and it
 * ends up getting scanned. Note that we only want to do this
 * fixup when we find the IXP4xx on a PrPMC system, which is why
 * we check the machine type. We could be running on a board
 * with an IXP4xx target device and we don't want to kill the
 * resources in that case.
 */
static void __devinit pci_fixup_prpmc1100(struct pci_dev *dev)
{
        int i;

        if (machine_is_prpmc1100()) {
                dev->class &= 0xff;
                dev->class |= PCI_CLASS_BRIDGE_HOST << 8;
                for (i = 0; i < PCI_NUM_RESOURCES; i++) {
                        dev->resource[i].start = 0;
                        dev->resource[i].end   = 0;
                        dev->resource[i].flags = 0;
                }
        }
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IXP4XX, pci_fixup_prpmc1100);

/*
 * PCI IDE controllers use non-standard I/O port decoding, respect it.
 */
static void __devinit pci_fixup_ide_bases(struct pci_dev *dev)
{
        struct resource *r;
        int i;

        if ((dev->class >> 8) != PCI_CLASS_STORAGE_IDE)
                return;

        for (i = 0; i < PCI_NUM_RESOURCES; i++) {
                r = dev->resource + i;
                if ((r->start & ~0x80) == 0x374) {
                        r->start |= 2;
                        r->end = r->start;
                }
        }
}
DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pci_fixup_ide_bases);

/*
 * Put the DEC21142 to sleep
 */
static void __devinit pci_fixup_dec21142(struct pci_dev *dev)
{
        pci_write_config_dword(dev, 0x40, 0x80000000);
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_DEC, PCI_DEVICE_ID_DEC_21142, pci_fixup_dec21142);

/*
 * The CY82C693 needs some rather major fixups to ensure that it does
 * the right thing.  Idea from the Alpha people, with a few additions.
 *
 * We ensure that the IDE base registers are set to 1f0/3f4 for the
 * primary bus, and 170/374 for the secondary bus.  Also, hide them
 * from the PCI subsystem view as well so we won't try to perform
 * our own auto-configuration on them.
 *
 * In addition, we ensure that the PCI IDE interrupts are routed to
 * IRQ 14 and IRQ 15 respectively.
 *
 * The above gets us to a point where the IDE on this device is
 * functional.  However, The CY82C693U _does not work_ in bus
 * master mode without locking the PCI bus solid.
 */
static void __devinit pci_fixup_cy82c693(struct pci_dev *dev)
{
        if ((dev->class >> 8) == PCI_CLASS_STORAGE_IDE) {
                u32 base0, base1;

                if (dev->class & 0x80) {        /* primary */
                        base0 = 0x1f0;
                        base1 = 0x3f4;
                } else {                        /* secondary */
                        base0 = 0x170;
                        base1 = 0x374;
                }

                pci_write_config_dword(dev, PCI_BASE_ADDRESS_0,
                                       base0 | PCI_BASE_ADDRESS_SPACE_IO);
                pci_write_config_dword(dev, PCI_BASE_ADDRESS_1,
                                       base1 | PCI_BASE_ADDRESS_SPACE_IO);

                dev->resource[0].start = 0;
                dev->resource[0].end   = 0;
                dev->resource[0].flags = 0;

                dev->resource[1].start = 0;
                dev->resource[1].end   = 0;
                dev->resource[1].flags = 0;
        } else if (PCI_FUNC(dev->devfn) == 0) {
                /*
                 * Setup IDE IRQ routing.
                 */
                pci_write_config_byte(dev, 0x4b, 14);
                pci_write_config_byte(dev, 0x4c, 15);

                /*
                 * Disable FREQACK handshake, enable USB.
                 */
                pci_write_config_byte(dev, 0x4d, 0x41);

                /*
                 * Enable PCI retry, and PCI post-write buffer.
                 */
                pci_write_config_byte(dev, 0x44, 0x17);

                /*
                 * Enable ISA master and DMA post write buffering.
                 */
                pci_write_config_byte(dev, 0x45, 0x03);
        }
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CONTAQ, PCI_DEVICE_ID_CONTAQ_82C693, pci_fixup_cy82c693);

static void __init pci_fixup_it8152(struct pci_dev *dev)
{
        int i;
        /* fixup for ITE 8152 devices */
        /* FIXME: add defines for class 0x68000 and 0x80103 */
        if ((dev->class >> 8) == PCI_CLASS_BRIDGE_HOST ||
            dev->class == 0x68000 ||
            dev->class == 0x80103) {
                for (i = 0; i < PCI_NUM_RESOURCES; i++) {
                        dev->resource[i].start = 0;
                        dev->resource[i].end   = 0;
                        dev->resource[i].flags = 0;
                }
        }
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ITE, PCI_DEVICE_ID_ITE_8152, pci_fixup_it8152);



void __devinit pcibios_update_irq(struct pci_dev *dev, int irq)
{
        if (debug_pci)
                printk("PCI: Assigning IRQ %02d to %s\n", irq, pci_name(dev));
        pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
}

/*
 * If the bus contains any of these devices, then we must not turn on
 * parity checking of any kind.  Currently this is CyberPro 20x0 only.
 */
static inline int pdev_bad_for_parity(struct pci_dev *dev)
{
        return ((dev->vendor == PCI_VENDOR_ID_INTERG &&
                 (dev->device == PCI_DEVICE_ID_INTERG_2000 ||
                  dev->device == PCI_DEVICE_ID_INTERG_2010)) ||
                (dev->vendor == PCI_VENDOR_ID_ITE &&
                 dev->device == PCI_DEVICE_ID_ITE_8152));

}

/*
 * Adjust the device resources from bus-centric to Linux-centric.
 */
static void __devinit
pdev_fixup_device_resources(struct pci_sys_data *root, struct pci_dev *dev)
{
        resource_size_t offset;
        int i;

        for (i = 0; i < PCI_NUM_RESOURCES; i++) {
                if (dev->resource[i].start == 0)
                        continue;
                if (dev->resource[i].flags & IORESOURCE_MEM)
                        offset = root->mem_offset;
                else
                        offset = root->io_offset;

                dev->resource[i].start += offset;
                dev->resource[i].end   += offset;
        }
}

static void __devinit
pbus_assign_bus_resources(struct pci_bus *bus, struct pci_sys_data *root)
{
        struct pci_dev *dev = bus->self;
        int i;

        if (!dev) {
                /*
                 * Assign root bus resources.
                 */
                for (i = 0; i < 3; i++)
                        bus->resource[i] = root->resource[i];
        }
}

/*
 * pcibios_fixup_bus - Called after each bus is probed,
 * but before its children are examined.
 */
void pcibios_fixup_bus(struct pci_bus *bus)
{
        struct pci_sys_data *root = bus->sysdata;
        struct pci_dev *dev;
        u16 features = PCI_COMMAND_SERR | PCI_COMMAND_PARITY | PCI_COMMAND_FAST_BACK;

        pbus_assign_bus_resources(bus, root);

        /*
         * Walk the devices on this bus, working out what we can
         * and can't support.
         */
        list_for_each_entry(dev, &bus->devices, bus_list) {
                u16 status;

                pdev_fixup_device_resources(root, dev);

                pci_read_config_word(dev, PCI_STATUS, &status);

                /*
                 * If any device on this bus does not support fast back
                 * to back transfers, then the bus as a whole is not able
                 * to support them.  Having fast back to back transfers
                 * on saves us one PCI cycle per transaction.
                 */
                if (!(status & PCI_STATUS_FAST_BACK))
                        features &= ~PCI_COMMAND_FAST_BACK;

                if (pdev_bad_for_parity(dev))
                        features &= ~(PCI_COMMAND_SERR | PCI_COMMAND_PARITY);

                switch (dev->class >> 8) {
                case PCI_CLASS_BRIDGE_PCI:
                        pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &status);
                        status |= PCI_BRIDGE_CTL_PARITY|PCI_BRIDGE_CTL_MASTER_ABORT;
                        status &= ~(PCI_BRIDGE_CTL_BUS_RESET|PCI_BRIDGE_CTL_FAST_BACK);
                        pci_write_config_word(dev, PCI_BRIDGE_CONTROL, status);
                        break;

                case PCI_CLASS_BRIDGE_CARDBUS:
                        pci_read_config_word(dev, PCI_CB_BRIDGE_CONTROL, &status);
                        status |= PCI_CB_BRIDGE_CTL_PARITY|PCI_CB_BRIDGE_CTL_MASTER_ABORT;
                        pci_write_config_word(dev, PCI_CB_BRIDGE_CONTROL, status);
                        break;
                }
        }

        /*
         * Now walk the devices again, this time setting them up.
         */
        list_for_each_entry(dev, &bus->devices, bus_list) {
                u16 cmd;

                pci_read_config_word(dev, PCI_COMMAND, &cmd);
                cmd |= features;
                pci_write_config_word(dev, PCI_COMMAND, cmd);

                pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE,
                                      L1_CACHE_BYTES >> 2);
        }

        /*
         * Propagate the flags to the PCI bridge.
         */
        if (bus->self && bus->self->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
                if (features & PCI_COMMAND_FAST_BACK)
                        bus->bridge_ctl |= PCI_BRIDGE_CTL_FAST_BACK;
                if (features & PCI_COMMAND_PARITY)
                        bus->bridge_ctl |= PCI_BRIDGE_CTL_PARITY;
        }

        /*
         * Report what we did for this bus
         */
        printk(KERN_INFO "PCI: bus%d: Fast back to back transfers %sabled\n",
                bus->number, (features & PCI_COMMAND_FAST_BACK) ? "en" : "dis");
}

/*
 * Convert from Linux-centric to bus-centric addresses for bridge devices.
 */
void
pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
                         struct resource *res)
{
        struct pci_sys_data *root = dev->sysdata;
        unsigned long offset = 0;

        if (res->flags & IORESOURCE_IO)
                offset = root->io_offset;
        if (res->flags & IORESOURCE_MEM)
                offset = root->mem_offset;

        region->start = res->start - offset;
        region->end   = res->end - offset;
}

void __devinit
pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
                        struct pci_bus_region *region)
{
        struct pci_sys_data *root = dev->sysdata;
        unsigned long offset = 0;

        if (res->flags & IORESOURCE_IO)
                offset = root->io_offset;
        if (res->flags & IORESOURCE_MEM)
                offset = root->mem_offset;

        res->start = region->start + offset;
        res->end   = region->end + offset;
}

#ifdef CONFIG_HOTPLUG
EXPORT_SYMBOL(pcibios_fixup_bus);
EXPORT_SYMBOL(pcibios_resource_to_bus);
EXPORT_SYMBOL(pcibios_bus_to_resource);
#endif

/*
 * This is the standard PCI-PCI bridge swizzling algorithm:
 *
 *   Dev: 0  1  2  3
 *    A   A  B  C  D
 *    B   B  C  D  A
 *    C   C  D  A  B
 *    D   D  A  B  C
 *        ^^^^^^^^^^ irq pin on bridge
 */
u8 __devinit pci_std_swizzle(struct pci_dev *dev, u8 *pinp)
{
        int pin = *pinp - 1;

        while (dev->bus->self) {
                pin = (pin + PCI_SLOT(dev->devfn)) & 3;
                /*
                 * move up the chain of bridges,
                 * swizzling as we go.
                 */
                dev = dev->bus->self;
        }
        *pinp = pin + 1;

        return PCI_SLOT(dev->devfn);
}

/*
 * Swizzle the device pin each time we cross a bridge.
 * This might update pin and returns the slot number.
 */
static u8 __devinit pcibios_swizzle(struct pci_dev *dev, u8 *pin)
{
        struct pci_sys_data *sys = dev->sysdata;
        int slot = 0, oldpin = *pin;

        if (sys->swizzle)
                slot = sys->swizzle(dev, pin);

        if (debug_pci)
                printk("PCI: %s swizzling pin %d => pin %d slot %d\n",
                        pci_name(dev), oldpin, *pin, slot);

        return slot;
}

/*
 * Map a slot/pin to an IRQ.
 */
static int pcibios_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
{
        struct pci_sys_data *sys = dev->sysdata;
        int irq = -1;

        if (sys->map_irq)
                irq = sys->map_irq(dev, slot, pin);

        if (debug_pci)
                printk("PCI: %s mapping slot %d pin %d => irq %d\n",
                        pci_name(dev), slot, pin, irq);

        return irq;
}

static void __init pcibios_init_hw(struct hw_pci *hw)
{
        struct pci_sys_data *sys = NULL;
        int ret;
        int nr, busnr;

        for (nr = busnr = 0; nr < hw->nr_controllers; nr++) {
                sys = kzalloc(sizeof(struct pci_sys_data), GFP_KERNEL);
                if (!sys)
                        panic("PCI: unable to allocate sys data!");

                sys->hw      = hw;
                sys->busnr   = busnr;
                sys->swizzle = hw->swizzle;
                sys->map_irq = hw->map_irq;
                sys->resource[0] = &ioport_resource;
                sys->resource[1] = &iomem_resource;

                ret = hw->setup(nr, sys);

                if (ret > 0) {
                        sys->bus = hw->scan(nr, sys);

                        if (!sys->bus)
                                panic("PCI: unable to scan bus!");

                        busnr = sys->bus->subordinate + 1;

                        list_add(&sys->node, &hw->buses);
                } else {
                        kfree(sys);
                        if (ret < 0)
                                break;
                }
        }
}

void __init pci_common_init(struct hw_pci *hw)
{
        struct pci_sys_data *sys;

        INIT_LIST_HEAD(&hw->buses);

        if (hw->preinit)
                hw->preinit();
        pcibios_init_hw(hw);
        if (hw->postinit)
                hw->postinit();

        pci_fixup_irqs(pcibios_swizzle, pcibios_map_irq);

        list_for_each_entry(sys, &hw->buses, node) {
                struct pci_bus *bus = sys->bus;

                if (!use_firmware) {
                        /*
                         * Size the bridge windows.
                         */
                        pci_bus_size_bridges(bus);

                        /*
                         * Assign resources.
                         */
                        pci_bus_assign_resources(bus);
                }

                /*
                 * Tell drivers about devices found.
                 */
                pci_bus_add_devices(bus);
        }
}

char * __init pcibios_setup(char *str)
{
        if (!strcmp(str, "debug")) {
                debug_pci = 1;
                return NULL;
        } else if (!strcmp(str, "firmware")) {
                use_firmware = 1;
                return NULL;
        }
        return str;
}

/*
 * From arch/i386/kernel/pci-i386.c:
 *
 * We need to avoid collisions with `mirrored' VGA ports
 * and other strange ISA hardware, so we always want the
 * addresses to be allocated in the 0x000-0x0ff region
 * modulo 0x400.
 *
 * Why? Because some silly external IO cards only decode
 * the low 10 bits of the IO address. The 0x00-0xff region
 * is reserved for motherboard devices that decode all 16
 * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
 * but we want to try to avoid allocating at 0x2900-0x2bff
 * which might be mirrored at 0x0100-0x03ff..
 */
void pcibios_align_resource(void *data, struct resource *res,
                            resource_size_t size, resource_size_t align)
{
        resource_size_t start = res->start;

        if (res->flags & IORESOURCE_IO && start & 0x300)
                start = (start + 0x3ff) & ~0x3ff;

        res->start = (start + align - 1) & ~(align - 1);
}

/**
 * pcibios_enable_device - Enable I/O and memory.
 * @dev: PCI device to be enabled
 */
int pcibios_enable_device(struct pci_dev *dev, int mask)
{
        u16 cmd, old_cmd;
        int idx;
        struct resource *r;

        pci_read_config_word(dev, PCI_COMMAND, &cmd);
        old_cmd = cmd;
        for (idx = 0; idx < 6; idx++) {
                /* Only set up the requested stuff */
                if (!(mask & (1 << idx)))
                        continue;

                r = dev->resource + idx;
                if (!r->start && r->end) {
                        printk(KERN_ERR "PCI: Device %s not available because"
                               " of resource collisions\n", pci_name(dev));
                        return -EINVAL;
                }
                if (r->flags & IORESOURCE_IO)
                        cmd |= PCI_COMMAND_IO;
                if (r->flags & IORESOURCE_MEM)
                        cmd |= PCI_COMMAND_MEMORY;
        }

        /*
         * Bridges (eg, cardbus bridges) need to be fully enabled
         */
        if ((dev->class >> 16) == PCI_BASE_CLASS_BRIDGE)
                cmd |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY;

        if (cmd != old_cmd) {
                printk("PCI: enabling device %s (%04x -> %04x)\n",
                       pci_name(dev), old_cmd, cmd);
                pci_write_config_word(dev, PCI_COMMAND, cmd);
        }
        return 0;
}

int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
                        enum pci_mmap_state mmap_state, int write_combine)
{
        struct pci_sys_data *root = dev->sysdata;
        unsigned long phys;

        if (mmap_state == pci_mmap_io) {
                return -EINVAL;
        } else {
                phys = vma->vm_pgoff + (root->mem_offset >> PAGE_SHIFT);
        }

        /*
         * Mark this as IO
         */
        vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);

        if (remap_pfn_range(vma, vma->vm_start, phys,
                             vma->vm_end - vma->vm_start,
                             vma->vm_page_prot))
                return -EAGAIN;

        return 0;
}