powerpc/swiotlb: Enable at early stage and disable if not necessary

Remove the dependency on PCI initialization for SWIOTLB initialization.
So that PCI can be initialized at proper time.

SWIOTLB is partly determined by PCI inbound/outbound map which is assigned
in PCI initialization. But swiotlb_init() should be done at the stage of
mem_init() which is much earlier than PCI initialization. So we reserve the
memory for SWIOTLB first and free it if not necessary.

All boards are converted to fit this change.

Signed-off-by: Jia Hongtao <B38951@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Acked-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/dma-swiotlb.c b/arch/powerpc/kernel/dma-swiotlb.c
index a720b54b971c..bd1a2aba599f 100644
--- a/arch/powerpc/kernel/dma-swiotlb.c
+++ b/arch/powerpc/kernel/dma-swiotlb.c
@@ -105,3 +105,23 @@ int __init swiotlb_setup_bus_notifier(void)
 			      &ppc_swiotlb_plat_bus_notifier);
 	return 0;
 }
+
+void swiotlb_detect_4g(void)
+{
+	if ((memblock_end_of_DRAM() - 1) > 0xffffffff)
+		ppc_swiotlb_enable = 1;
+}
+
+static int __init swiotlb_late_init(void)
+{
+	if (ppc_swiotlb_enable) {
+		swiotlb_print_info();
+		set_pci_dma_ops(&swiotlb_dma_ops);
+		ppc_md.pci_dma_dev_setup = pci_dma_dev_setup_swiotlb;
+	} else {
+		swiotlb_free();
+	}
+
+	return 0;
+}
+subsys_initcall(swiotlb_late_init);