/*
 * IO workarounds for PCI on Celleb/Cell platform
 *
 * (C) Copyright 2006-2007 TOSHIBA CORPORATION
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#undef DEBUG

#include <linux/kernel.h>
#include <linux/of_platform.h>
#include <linux/io.h>

#include <asm/ppc-pci.h>
#include <asm/pci-bridge.h>

#include "io-workarounds.h"

#define SPIDER_PCI_DISABLE_PREFETCH

struct spiderpci_iowa_private {
        void __iomem *regs;
};

static void spiderpci_io_flush(struct iowa_bus *bus)
{
        struct spiderpci_iowa_private *priv;
        u32 val;

        priv = bus->private;
        val = in_be32(priv->regs + SPIDER_PCI_DUMMY_READ);
        iosync();
}

#define SPIDER_PCI_MMIO_READ(name, ret)                                 \
static ret spiderpci_##name(const PCI_IO_ADDR addr)                     \
{                                                                       \
        ret val = __do_##name(addr);                                    \
        spiderpci_io_flush(iowa_mem_find_bus(addr));                    \
        return val;                                                     \
}

#define SPIDER_PCI_MMIO_READ_STR(name)                                  \
static void spiderpci_##name(const PCI_IO_ADDR addr, void *buf,         \
                             unsigned long count)                       \
{                                                                       \
        __do_##name(addr, buf, count);                                  \
        spiderpci_io_flush(iowa_mem_find_bus(addr));                    \
}

SPIDER_PCI_MMIO_READ(readb, u8)
SPIDER_PCI_MMIO_READ(readw, u16)
SPIDER_PCI_MMIO_READ(readl, u32)
SPIDER_PCI_MMIO_READ(readq, u64)
SPIDER_PCI_MMIO_READ(readw_be, u16)
SPIDER_PCI_MMIO_READ(readl_be, u32)
SPIDER_PCI_MMIO_READ(readq_be, u64)
SPIDER_PCI_MMIO_READ_STR(readsb)
SPIDER_PCI_MMIO_READ_STR(readsw)
SPIDER_PCI_MMIO_READ_STR(readsl)

static void spiderpci_memcpy_fromio(void *dest, const PCI_IO_ADDR src,
                                    unsigned long n)
{
        __do_memcpy_fromio(dest, src, n);
        spiderpci_io_flush(iowa_mem_find_bus(src));
}

static int __init spiderpci_pci_setup_chip(struct pci_controller *phb,
                                           void __iomem *regs)
{
        void *dummy_page_va;
        dma_addr_t dummy_page_da;

#ifdef SPIDER_PCI_DISABLE_PREFETCH
        u32 val = in_be32(regs + SPIDER_PCI_VCI_CNTL_STAT);
        pr_debug("SPIDER_IOWA:PVCI_Control_Status was 0x%08x\n", val);
        out_be32(regs + SPIDER_PCI_VCI_CNTL_STAT, val | 0x8);
#endif /* SPIDER_PCI_DISABLE_PREFETCH */

        /* setup dummy read */
        /*
         * On CellBlade, we can't know that which XDR memory is used by
         * kmalloc() to allocate dummy_page_va.
         * In order to imporve the performance, the XDR which is used to
         * allocate dummy_page_va is the nearest the spider-pci.
         * We have to select the CBE which is the nearest the spider-pci
         * to allocate memory from the best XDR, but I don't know that
         * how to do.
         *
         * Celleb does not have this problem, because it has only one XDR.
         */
        dummy_page_va = kmalloc(PAGE_SIZE, GFP_KERNEL);
        if (!dummy_page_va) {
                pr_err("SPIDERPCI-IOWA:Alloc dummy_page_va failed.\n");
                return -1;
        }

        dummy_page_da = dma_map_single(phb->parent, dummy_page_va,
                                       PAGE_SIZE, DMA_FROM_DEVICE);
        if (dma_mapping_error(phb->parent, dummy_page_da)) {
                pr_err("SPIDER-IOWA:Map dummy page filed.\n");
                kfree(dummy_page_va);
                return -1;
        }

        out_be32(regs + SPIDER_PCI_DUMMY_READ_BASE, dummy_page_da);

        return 0;
}

int __init spiderpci_iowa_init(struct iowa_bus *bus, void *data)
{
        void __iomem *regs = NULL;
        struct spiderpci_iowa_private *priv;
        struct device_node *np = bus->phb->dn;
        struct resource r;
        unsigned long offset = (unsigned long)data;

        pr_debug("SPIDERPCI-IOWA:Bus initialize for spider(%s)\n",
                 np->full_name);

        priv = kzalloc(sizeof(struct spiderpci_iowa_private), GFP_KERNEL);
        if (!priv) {
                pr_err("SPIDERPCI-IOWA:"
                       "Can't allocate struct spiderpci_iowa_private");
                return -1;
        }

        if (of_address_to_resource(np, 0, &r)) {
                pr_err("SPIDERPCI-IOWA:Can't get resource.\n");
                goto error;
        }

        regs = ioremap(r.start + offset, SPIDER_PCI_REG_SIZE);
        if (!regs) {
                pr_err("SPIDERPCI-IOWA:ioremap failed.\n");
                goto error;
        }
        priv->regs = regs;
        bus->private = priv;

        if (spiderpci_pci_setup_chip(bus->phb, regs))
                goto error;

        return 0;

error:
        kfree(priv);
        bus->private = NULL;

        if (regs)
                iounmap(regs);

        return -1;
}

struct ppc_pci_io spiderpci_ops = {
        .readb = spiderpci_readb,
        .readw = spiderpci_readw,
        .readl = spiderpci_readl,
        .readq = spiderpci_readq,
        .readw_be = spiderpci_readw_be,
        .readl_be = spiderpci_readl_be,
        .readq_be = spiderpci_readq_be,
        .readsb = spiderpci_readsb,
        .readsw = spiderpci_readsw,
        .readsl = spiderpci_readsl,
        .memcpy_fromio = spiderpci_memcpy_fromio,
};