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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/ia64/hp/common/hwsw_iommu.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/ia64/hp/common/hwsw_iommu.c')
-rw-r--r--kernel/arch/ia64/hp/common/hwsw_iommu.c59
1 files changed, 59 insertions, 0 deletions
diff --git a/kernel/arch/ia64/hp/common/hwsw_iommu.c b/kernel/arch/ia64/hp/common/hwsw_iommu.c
new file mode 100644
index 000000000..1e4cae5ae
--- /dev/null
+++ b/kernel/arch/ia64/hp/common/hwsw_iommu.c
@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2004 Hewlett-Packard Development Company, L.P.
+ * Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
+ *
+ * This is a pseudo I/O MMU which dispatches to the hardware I/O MMU
+ * whenever possible. We assume that the hardware I/O MMU requires
+ * full 32-bit addressability, as is the case, e.g., for HP zx1-based
+ * systems (there, the I/O MMU window is mapped at 3-4GB). If a
+ * device doesn't provide full 32-bit addressability, we fall back on
+ * the sw I/O TLB. This is good enough to let us support broken
+ * hardware such as soundcards which have a DMA engine that can
+ * address only 28 bits.
+ */
+
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/swiotlb.h>
+#include <linux/export.h>
+#include <asm/machvec.h>
+
+extern struct dma_map_ops sba_dma_ops, swiotlb_dma_ops;
+
+/* swiotlb declarations & definitions: */
+extern int swiotlb_late_init_with_default_size (size_t size);
+
+/*
+ * Note: we need to make the determination of whether or not to use
+ * the sw I/O TLB based purely on the device structure. Anything else
+ * would be unreliable or would be too intrusive.
+ */
+static inline int use_swiotlb(struct device *dev)
+{
+ return dev && dev->dma_mask &&
+ !sba_dma_ops.dma_supported(dev, *dev->dma_mask);
+}
+
+struct dma_map_ops *hwsw_dma_get_ops(struct device *dev)
+{
+ if (use_swiotlb(dev))
+ return &swiotlb_dma_ops;
+ return &sba_dma_ops;
+}
+EXPORT_SYMBOL(hwsw_dma_get_ops);
+
+void __init
+hwsw_init (void)
+{
+ /* default to a smallish 2MB sw I/O TLB */
+ if (swiotlb_late_init_with_default_size (2 * (1<<20)) != 0) {
+#ifdef CONFIG_IA64_GENERIC
+ /* Better to have normal DMA than panic */
+ printk(KERN_WARNING "%s: Failed to initialize software I/O TLB,"
+ " reverting to hpzx1 platform vector\n", __func__);
+ machvec_init("hpzx1");
+#else
+ panic("Unable to initialize software I/O TLB services");
+#endif
+ }
+}