pci-noop.c

Go to the documentation of this file.

/*
 *  linux/arch/alpha/kernel/pci-noop.c
 *
 * Stub PCI interfaces for Jensen-specific kernels.
 */

#include <linux/pci.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/gfp.h>
#include <linux/capability.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/dma-mapping.h>
#include <linux/scatterlist.h>

#include "proto.h"


/*
 * The PCI controller list.
 */

struct pci_controller *hose_head, **hose_tail = &hose_head;
struct pci_controller *pci_isa_hose;


struct pci_controller * __init
alloc_pci_controller(void)
{
    struct pci_controller *hose;

    hose = alloc_bootmem(sizeof(*hose));

    *hose_tail = hose;
    hose_tail = &hose->next;

    return hose;
}

struct resource * __init
alloc_resource(void)
{
    struct resource *res;

    res = alloc_bootmem(sizeof(*res));

    return res;
}

asmlinkage long
sys_pciconfig_iobase(long which, unsigned long bus, unsigned long dfn)
{
    struct pci_controller *hose;

    /* from hose or from bus.devfn */
    if (which & IOBASE_FROM_HOSE) {
        for (hose = hose_head; hose; hose = hose->next) 
            if (hose->index == bus)
                break;
        if (!hose)
            return -ENODEV;
    } else {
        /* Special hook for ISA access.  */
        if (bus == 0 && dfn == 0)
            hose = pci_isa_hose;
        else
            return -ENODEV;
    }

    switch (which & ~IOBASE_FROM_HOSE) {
    case IOBASE_HOSE:
        return hose->index;
    case IOBASE_SPARSE_MEM:
        return hose->sparse_mem_base;
    case IOBASE_DENSE_MEM:
        return hose->dense_mem_base;
    case IOBASE_SPARSE_IO:
        return hose->sparse_io_base;
    case IOBASE_DENSE_IO:
        return hose->dense_io_base;
    case IOBASE_ROOT_BUS:
        return hose->bus->number;
    }

    return -EOPNOTSUPP;
}

asmlinkage long
sys_pciconfig_read(unsigned long bus, unsigned long dfn,
           unsigned long off, unsigned long len, void *buf)
{
    if (!capable(CAP_SYS_ADMIN))
        return -EPERM;
    else
        return -ENODEV;
}

asmlinkage long
sys_pciconfig_write(unsigned long bus, unsigned long dfn,
            unsigned long off, unsigned long len, void *buf)
{
    if (!capable(CAP_SYS_ADMIN))
        return -EPERM;
    else
        return -ENODEV;
}

static void *alpha_noop_alloc_coherent(struct device *dev, size_t size,
                       dma_addr_t *dma_handle, gfp_t gfp,
                       struct dma_attrs *attrs)
{
    void *ret;

    if (!dev || *dev->dma_mask >= 0xffffffffUL)
        gfp &= ~GFP_DMA;
    ret = (void *)__get_free_pages(gfp, get_order(size));
    if (ret) {
        memset(ret, 0, size);
        *dma_handle = virt_to_phys(ret);
    }
    return ret;
}

static void alpha_noop_free_coherent(struct device *dev, size_t size,
                     void *cpu_addr, dma_addr_t dma_addr,
                     struct dma_attrs *attrs)
{
    free_pages((unsigned long)cpu_addr, get_order(size));
}

static dma_addr_t alpha_noop_map_page(struct device *dev, struct page *page,
                      unsigned long offset, size_t size,
                      enum dma_data_direction dir,
                      struct dma_attrs *attrs)
{
    return page_to_pa(page) + offset;
}

static int alpha_noop_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
                 enum dma_data_direction dir, struct dma_attrs *attrs)
{
    int i;
    struct scatterlist *sg;

    for_each_sg(sgl, sg, nents, i) {
        void *va;

        BUG_ON(!sg_page(sg));
        va = sg_virt(sg);
        sg_dma_address(sg) = (dma_addr_t)virt_to_phys(va);
        sg_dma_len(sg) = sg->length;
    }

    return nents;
}

static int alpha_noop_mapping_error(struct device *dev, dma_addr_t dma_addr)
{
    return 0;
}

static int alpha_noop_supported(struct device *dev, u64 mask)
{
    return mask < 0x00ffffffUL ? 0 : 1;
}

static int alpha_noop_set_mask(struct device *dev, u64 mask)
{
    if (!dev->dma_mask || !dma_supported(dev, mask))
        return -EIO;

    *dev->dma_mask = mask;
    return 0;
}

struct dma_map_ops alpha_noop_ops = {
    .alloc          = alpha_noop_alloc_coherent,
    .free           = alpha_noop_free_coherent,
    .map_page       = alpha_noop_map_page,
    .map_sg         = alpha_noop_map_sg,
    .mapping_error      = alpha_noop_mapping_error,
    .dma_supported      = alpha_noop_supported,
    .set_dma_mask       = alpha_noop_set_mask,
};

struct dma_map_ops *dma_ops = &alpha_noop_ops;
EXPORT_SYMBOL(dma_ops);