Linux with MMU on NEEK

Hi, all.

I'm testing Linux MMU version, on my NEEK.

http://www.nioswiki.com/linux

It works fine and I can use "bash" shell. This is the evident proof that we are using the true 'fork' instead of 'vfork'.

May be this will depends on the version, but TSE driver claims an error and doesn't work on this design. The error is

ERROR: altera_tse.c:1666: request_mem_region() failed

I think that this error is caused by misunderstanding of the usage for the function request_mem_region(). Inside of the request_mem_region(), the function __request_region() is called. If the resource has been already registered, this function returns a non-NULL value, that is the pointer for its resource. But the resource 'sgdma_rx_base' is already registered in the initialization process, so this function returns the 'conflict' and

    if (!request_mem_region(sgdma_rx_base, sgdma_rx_size, "altera_tse")) {

is always true. So I made a dirty patch,

    if (!request_mem_region(sgdma_rx_base, sgdma_rx_size, "altera_tse")) {
        reg_resource = __request_region(&iomem_resource, sgdma_rx_base, sgdma_rx_size, "altera_tse", 0);
        if (reg_resource != NULL && reg_resource->flags & IORESOURCE_BUSY) {
            printk(KERN_ERR "ERROR: %s:%d: request_mem_region() failed\n", __FILE__, __LINE__);
            ret = -EBUSY;
            goto out_sgdma_rx;
        }
    }

Moreover, the author is forgetting that the DMA is working in the physical address world,

so we need to set the pointers of descripters like

//    desc->source = read_addr;
    desc->source = virt_to_phys(read_addr);
//    desc->destination = write_addr;
    desc->destination = virt_to_phys(write_addr);
//    desc->next = (unsigned int *)next;
    desc->next = (unsigned int *)((unsigned long)next & 0x1fffffffUL);

and so on.

Also the frame buffer fb0 will not work well, because the driver 'altfb.c' is not implemented for Linux with MMU version. So I put some codes for altfb_mmap(), like

/* We implement our own mmap to set MAY_SHARE and add the correct size */
static int altfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
{
    unsigned long phys_addr, phys_size;
    unsigned long addr;
    unsigned long size = vma->vm_end - vma->vm_start;
    unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
//    vma->vm_flags |= VM_MAYSHARE | VM_SHARED;
//    vma->vm_start = info->screen_base;
//    vma->vm_end = vma->vm_start + info->fix.smem_len;
    /* check range */
    if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
        return -EINVAL;
    if (offset + size > altfb_fix.smem_len)
        return -EINVAL;
    vma->vm_flags |= VM_IO | VM_RESERVED;
    addr = vma->vm_start;
    phys_addr = altfb_fix.smem_start + offset;
    if ((offset + size) < altfb_fix.smem_len)
        phys_size = size;
    else
        phys_size = altfb_fix.smem_len - offset;
    vma->vm_page_prot = __pgprot(_PAGE_PRESENT|_PAGE_READ|_PAGE_WRITE);
    if (remap_pfn_range(vma, addr, phys_addr >> PAGE_SHIFT, phys_size, vma->vm_page_prot))
        return -EAGAIN;
    return 0;
}

and rewrite the DMA descripters like

            desc->next = (void *)virt_to_phys((desc + 1));

So now, I can evoke telnetd and control NEEK through ethernet, and use Nano-X on Linux MMU version, but can't enter ftp session, because 'getservbyname()' function will not work well.

I don't know the directory that the souce of 'getservbyname()' is included. Would anyone please tell me where is it?

Thank you, in advance.