Re: [RFC][PATCHSET] PC-9800 architecture (CORE only)

[Osamu Tomita]

Alan Cox wrote:
> 
> On Tue, 2002-10-22 at 16:36, Osamu Tomita wrote:
> > IORESOURCE98_SPARSE flag means odd or even only addressing.
> > We modify check_region(), request_region() and release_region().
> > If length parameter has negative value, addressing is sparse.
> > For example,
> >  request_region(0x100, -5, "xxx"); gets 0x100, 0x102 and 0x104.
> 
> Does PC-9800 ever have devices on 0x100/2/4/8 overlapping another device
> on 0x101/103/105 ?
Yes.
Here is io resource definition for PC-9800. (extract from patch)
struct resource standard_io_resources[] = {
        { "pic1", 0x00, 0x02, IORESOURCE_BUSY | IORESOURCE98_SPARSE},
        { "dma", 0x01, 0x2d, IORESOURCE_BUSY | IORESOURCE98_SPARSE },
        { "pic2", 0x08, 0x0a, IORESOURCE_BUSY | IORESOURCE98_SPARSE },
        { "calender clock", 0x20, 0x22, IORESOURCE98_SPARSE },
PIC1 uses 0x00 and 0x02.
DMA controler uses 0x01, 0x03, 0x05,....0x2d.
PIC2 uses 0x08 and 0x0a.
RTC uses 0x20 and 0x22.
They are overlapping.

Regards
Osamu Tomita