[PATCH] initialize TCE tables

A fairly recent platform requirement states that the OS must clear the
whole TCE table at setup time, in case firmware left any active
mappings in it.  Without this initialization, dynamic bus removes can
fail.  Firmware rejects these requests if active mappings still exist 
for a slot that has been deallocated by the OS.

Signed-off-by: John Rose <johnrose@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/ppc64/kernel/iommu.c b/arch/ppc64/kernel/iommu.c
index 344164681d2c..8316426ccaf6 100644
--- a/arch/ppc64/kernel/iommu.c
+++ b/arch/ppc64/kernel/iommu.c
@@ -423,6 +423,9 @@ struct iommu_table *iommu_init_table(struct iommu_table *tbl)
         tbl->it_largehint = tbl->it_halfpoint;
         spin_lock_init(&tbl->it_lock);
 
+        /* Clear the hardware table in case firmware left allocations in it */
+        ppc_md.tce_free(tbl, tbl->it_offset, tbl->it_size);
+
         if (!welcomed) {
                 printk(KERN_INFO "IOMMU table initialized, virtual merging %s\n",
                        novmerge ? "disabled" : "enabled");