test: Add test for IOMMU uclass map/unmap ops

Test that the map and unmap operations work for devices that
have DMA translated by an IOMMU and devices that don't have
DMA translated by an IOMMU.

Signed-off-by: Mark Kettenis <kettenis@openbsd.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

1 files changed, 58 insertions, 0 deletions

diff --git a/drivers/iommu/sandbox_iommu.c b/drivers/iommu/sandbox_iommu.c
index c8161a40aef..6ceb7fd5ec3 100644
--- a/drivers/iommu/sandbox_iommu.c
+++ b/drivers/iommu/sandbox_iommu.c
@@ -5,6 +5,61 @@
 
 #include <common.h>
 #include <dm.h>
+#include <iommu.h>
+#include <lmb.h>
+#include <asm/io.h>
+#include <linux/sizes.h>
+
+#define IOMMU_PAGE_SIZE		SZ_4K
+
+struct sandbox_iommu_priv {
+	struct lmb lmb;
+};
+
+static dma_addr_t sandbox_iommu_map(struct udevice *dev, void *addr,
+				    size_t size)
+{
+	struct sandbox_iommu_priv *priv = dev_get_priv(dev);
+	phys_addr_t paddr, dva;
+	phys_size_t psize, off;
+
+	paddr = ALIGN_DOWN(virt_to_phys(addr), IOMMU_PAGE_SIZE);
+	off = virt_to_phys(addr) - paddr;
+	psize = ALIGN(size + off, IOMMU_PAGE_SIZE);
+
+	dva = lmb_alloc(&priv->lmb, psize, IOMMU_PAGE_SIZE);
+
+	return dva + off;
+}
+
+static void sandbox_iommu_unmap(struct udevice *dev, dma_addr_t addr,
+				size_t size)
+{
+	struct sandbox_iommu_priv *priv = dev_get_priv(dev);
+	phys_addr_t dva;
+	phys_size_t psize;
+
+	dva = ALIGN_DOWN(addr, IOMMU_PAGE_SIZE);
+	psize = size + (addr - dva);
+	psize = ALIGN(psize, IOMMU_PAGE_SIZE);
+
+	lmb_free(&priv->lmb, dva, psize);
+}
+
+static struct iommu_ops sandbox_iommu_ops = {
+	.map = sandbox_iommu_map,
+	.unmap = sandbox_iommu_unmap,
+};
+
+static int sandbox_iommu_probe(struct udevice *dev)
+{
+	struct sandbox_iommu_priv *priv = dev_get_priv(dev);
+
+	lmb_init(&priv->lmb);
+	lmb_add(&priv->lmb, 0x89abc000, SZ_16K);
+
+	return 0;
+}
 
 static const struct udevice_id sandbox_iommu_ids[] = {
 	{ .compatible = "sandbox,iommu" },
@@ -15,4 +70,7 @@ U_BOOT_DRIVER(sandbox_iommu) = {
 	.name = "sandbox_iommu",
 	.id = UCLASS_IOMMU,
 	.of_match = sandbox_iommu_ids,
+	.priv_auto = sizeof(struct sandbox_iommu_priv),
+	.ops = &sandbox_iommu_ops,
+	.probe = sandbox_iommu_probe,
 };