diff options
Diffstat (limited to 'src/devices/pnp_device.c')
| -rw-r--r-- | src/devices/pnp_device.c | 31 |
1 files changed, 26 insertions, 5 deletions
diff --git a/src/devices/pnp_device.c b/src/devices/pnp_device.c index 70286ad..cde571f 100644 --- a/src/devices/pnp_device.c +++ b/src/devices/pnp_device.c @@ -132,7 +132,7 @@ struct device_operations pnp_ops = { static void pnp_get_ioresource(device_t dev, unsigned index, struct io_info *info) { struct resource *resource; - uint32_t size; + unsigned moving, gran, step; resource = new_resource(dev, index); @@ -140,11 +140,32 @@ static void pnp_get_ioresource(device_t dev, unsigned index, struct io_info *inf resource->limit = 0xffff; resource->flags |= IORESOURCE_IO; + /* Get the resource size */ + moving = info->mask; + gran = 15; + step = 1 << gran; + /* Find the first bit that moves */ + while((moving & step) == 0) { + gran--; + step >>= 1; + } + /* Now find the first bit that does not move */ + while((moving & step) != 0) { + gran--; + step >>= 1; + } + /* Of the moving bits the last bit in the first group, + * tells us the size of this resource. + */ + if ((moving & step) == 0) { + gran++; + step <<= 1; + } /* Set the resource size and alignment */ - size = (0xffff & info->mask); - resource->size = (~(size | 0xfffff800) + 1); - resource->align = log2(resource->size); - resource->gran = resource->align; + resource->gran = gran; + resource->align = gran; + resource->limit = info->mask | (step - 1); + resource->size = 1 << gran; } static void get_resources(device_t dev, struct pnp_info *info) |
