Merge branch 'master' into csb1725

[mv-sheeva.git] / arch / x86 / kernel / resource.c

diff --git a/arch/x86/kernel/resource.c b/arch/x86/kernel/resource.c
new file mode 100644 (file)
index 0000000..2a26819
--- /dev/null
+++ b/arch/x86/kernel/resource.c
@@ -0,0 +1,48 @@
+#include <linux/ioport.h>
+#include <asm/e820.h>
+
+static void resource_clip(struct resource *res, resource_size_t start,
+                         resource_size_t end)
+{
+       resource_size_t low = 0, high = 0;
+
+       if (res->end < start || res->start > end)
+               return;         /* no conflict */
+
+       if (res->start < start)
+               low = start - res->start;
+
+       if (res->end > end)
+               high = res->end - end;
+
+       /* Keep the area above or below the conflict, whichever is larger */
+       if (low > high)
+               res->end = start - 1;
+       else
+               res->start = end + 1;
+}
+
+static void remove_e820_regions(struct resource *avail)
+{
+       int i;
+       struct e820entry *entry;
+
+       for (i = 0; i < e820.nr_map; i++) {
+               entry = &e820.map[i];
+
+               resource_clip(avail, entry->addr,
+                             entry->addr + entry->size - 1);
+       }
+}
+
+void arch_remove_reservations(struct resource *avail)
+{
+       /* Trim out BIOS areas (low 1MB and high 2MB) and E820 regions */
+       if (avail->flags & IORESOURCE_MEM) {
+               if (avail->start < BIOS_END)
+                       avail->start = BIOS_END;
+               resource_clip(avail, BIOS_ROM_BASE, BIOS_ROM_END);
+
+               remove_e820_regions(avail);
+       }
+}