[SPARC64]: Move ramdisk discovery code out to seperate function.
And add some comments explaining all of the quirks involved in
the way the bootloader provides this information.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc64/mm/init.c b/arch/sparc64/mm/init.c
index f37078d..21e9267 100644
--- a/arch/sparc64/mm/init.c
+++ b/arch/sparc64/mm/init.c
@@ -883,6 +883,37 @@
}
}
+static void __init find_ramdisk(unsigned long phys_base)
+{
+#ifdef CONFIG_BLK_DEV_INITRD
+ if (sparc_ramdisk_image || sparc_ramdisk_image64) {
+ unsigned long ramdisk_image;
+
+ /* Older versions of the bootloader only supported a
+ * 32-bit physical address for the ramdisk image
+ * location, stored at sparc_ramdisk_image. Newer
+ * SILO versions set sparc_ramdisk_image to zero and
+ * provide a full 64-bit physical address at
+ * sparc_ramdisk_image64.
+ */
+ ramdisk_image = sparc_ramdisk_image;
+ if (!ramdisk_image)
+ ramdisk_image = sparc_ramdisk_image64;
+
+ /* Another bootloader quirk. The bootloader normalizes
+ * the physical address to KERNBASE, so we have to
+ * factor that back out and add in the lowest valid
+ * physical page address to get the true physical address.
+ */
+ ramdisk_image -= KERNBASE;
+ ramdisk_image += phys_base;
+
+ initrd_start = ramdisk_image;
+ initrd_end = ramdisk_image + sparc_ramdisk_size;
+ }
+#endif
+}
+
/* About pages_avail, this is the value we will use to calculate
* the zholes_size[] argument given to free_area_init_node(). The
* page allocator uses this to calculate nr_kernel_pages,
@@ -912,30 +943,6 @@
bytes_avail += pavail[i].reg_size;
}
- /* Determine the location of the initial ramdisk before trying
- * to honor the "mem=xxx" command line argument. We must know
- * where the kernel image and the ramdisk image are so that we
- * do not trim those two areas from the physical memory map.
- */
-
-#ifdef CONFIG_BLK_DEV_INITRD
- /* Now have to check initial ramdisk, so that bootmap does not overwrite it */
- if (sparc_ramdisk_image || sparc_ramdisk_image64) {
- unsigned long ramdisk_image = sparc_ramdisk_image ?
- sparc_ramdisk_image : sparc_ramdisk_image64;
- ramdisk_image -= KERNBASE;
- initrd_start = ramdisk_image + phys_base;
- initrd_end = initrd_start + sparc_ramdisk_size;
- if (initrd_end > end_of_phys_memory) {
- printk(KERN_CRIT "initrd extends beyond end of memory "
- "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
- initrd_end, end_of_phys_memory);
- initrd_start = 0;
- initrd_end = 0;
- }
- }
-#endif
-
if (cmdline_memory_size &&
bytes_avail > cmdline_memory_size)
trim_pavail(&bytes_avail,
@@ -1337,6 +1344,8 @@
for (i = 0; i < pavail_ents; i++)
phys_base = min(phys_base, pavail[i].phys_addr);
+ find_ramdisk(phys_base);
+
set_bit(0, mmu_context_bmap);
shift = kern_base + PAGE_OFFSET - ((unsigned long)KERNBASE);