axi: Add AXI sandbox driver and simple emulator
Add test infrastructure and tests for the AXI uclass.
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Mario Six <mario.six@gdsys.cc>
diff --git a/drivers/axi/axi_sandbox.c b/drivers/axi/axi_sandbox.c
new file mode 100644
index 0000000..b91c91f
--- /dev/null
+++ b/drivers/axi/axi_sandbox.c
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2018
+ * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc
+ */
+
+#include <common.h>
+#include <axi.h>
+#include <dm.h>
+#include <asm/axi.h>
+
+/*
+ * This driver implements a AXI bus for the sandbox architecture for testing
+ * purposes.
+ *
+ * The bus forwards every access to it to a special AXI emulation device (which
+ * it gets via the axi_emul_get_ops function) that implements a simple
+ * read/write storage.
+ *
+ * The emulator device must still be contained in the device tree in the usual
+ * way, since configuration data for the storage is read from the DT.
+ */
+
+static int axi_sandbox_read(struct udevice *bus, ulong address, void *data,
+ enum axi_size_t size)
+{
+ struct axi_emul_ops *ops;
+ struct udevice *emul;
+ int ret;
+
+ /* Get emulator device */
+ ret = axi_sandbox_get_emul(bus, address, size, &emul);
+ if (ret)
+ return ret == -ENODEV ? 0 : ret;
+ /* Forward all reads to the AXI emulator */
+ ops = axi_emul_get_ops(emul);
+ if (!ops || !ops->read)
+ return -ENOSYS;
+
+ return ops->read(emul, address, data, size);
+}
+
+static int axi_sandbox_write(struct udevice *bus, ulong address, void *data,
+ enum axi_size_t size)
+{
+ struct axi_emul_ops *ops;
+ struct udevice *emul;
+ int ret;
+
+ /* Get emulator device */
+ ret = axi_sandbox_get_emul(bus, address, size, &emul);
+ if (ret)
+ return ret == -ENODEV ? 0 : ret;
+ /* Forward all writes to the AXI emulator */
+ ops = axi_emul_get_ops(emul);
+ if (!ops || !ops->write)
+ return -ENOSYS;
+
+ return ops->write(emul, address, data, size);
+}
+
+static const struct udevice_id axi_sandbox_ids[] = {
+ { .compatible = "sandbox,axi" },
+ { /* sentinel */ }
+};
+
+static const struct axi_ops axi_sandbox_ops = {
+ .read = axi_sandbox_read,
+ .write = axi_sandbox_write,
+};
+
+U_BOOT_DRIVER(axi_sandbox_bus) = {
+ .name = "axi_sandbox_bus",
+ .id = UCLASS_AXI,
+ .of_match = axi_sandbox_ids,
+ .ops = &axi_sandbox_ops,
+};