powerpc/powernv/ioda/ioda2: Rework TCE invalidation in tce_build()/tce_free()

The pnv_pci_ioda_tce_invalidate() helper invalidates TCE cache. It is
supposed to be called on IODA1/2 and not called on p5ioc2. It receives
start and end host addresses of TCE table.

IODA2 actually needs PCI addresses to invalidate the cache. Those
can be calculated from host addresses but since we are going
to implement multi-level TCE tables, calculating PCI address from
a host address might get either tricky or ugly as TCE table remains flat
on PCI bus but not in RAM.

This moves pnv_pci_ioda_tce_invalidate() from generic pnv_tce_build/
pnt_tce_free and defines IODA1/2-specific callbacks which call generic
ones and do PHB-model-specific TCE cache invalidation. P5IOC2 keeps
using generic callbacks as before.

This changes pnv_pci_ioda2_tce_invalidate() to receives TCE index and
number of pages which are PCI addresses shifted by IOMMU page shift.

No change in behaviour is expected.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 4 insertions, 13 deletions

diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
index 2793b9d..f72fc6e 100644
--- a/arch/powerpc/platforms/powernv/pci.c
+++ b/arch/powerpc/platforms/powernv/pci.c
@@ -577,37 +577,28 @@ int pnv_tce_build(struct iommu_table *tbl, long index, long npages,
 		struct dma_attrs *attrs)
 {
 	u64 proto_tce = iommu_direction_to_tce_perm(direction);
-	__be64 *tcep, *tces;
+	__be64 *tcep;
 	u64 rpn;
 
-	tces = tcep = ((__be64 *)tbl->it_base) + index - tbl->it_offset;
+	tcep = ((__be64 *)tbl->it_base) + index - tbl->it_offset;
 	rpn = __pa(uaddr) >> tbl->it_page_shift;
 
 	while (npages--)
 		*(tcep++) = cpu_to_be64(proto_tce |
 				(rpn++ << tbl->it_page_shift));
 
-	/* Some implementations won't cache invalid TCEs and thus may not
-	 * need that flush. We'll probably turn it_type into a bit mask
-	 * of flags if that becomes the case
-	 */
-	if (tbl->it_type & TCE_PCI_SWINV_CREATE)
-		pnv_pci_ioda_tce_invalidate(tbl, tces, tcep - 1, false);
 
 	return 0;
 }
 
 void pnv_tce_free(struct iommu_table *tbl, long index, long npages)
 {
-	__be64 *tcep, *tces;
+	__be64 *tcep;
 
-	tces = tcep = ((__be64 *)tbl->it_base) + index - tbl->it_offset;
+	tcep = ((__be64 *)tbl->it_base) + index - tbl->it_offset;
 
 	while (npages--)
 		*(tcep++) = cpu_to_be64(0);
-
-	if (tbl->it_type & TCE_PCI_SWINV_FREE)
-		pnv_pci_ioda_tce_invalidate(tbl, tces, tcep - 1, false);
 }
 
 unsigned long pnv_tce_get(struct iommu_table *tbl, long index)