@@ -50,6 +50,8 @@ source "drivers/i2c/Kconfig"
source "drivers/input/Kconfig"
+source "drivers/iommu/Kconfig"
+
source "drivers/led/Kconfig"
source "drivers/mailbox/Kconfig"
@@ -102,6 +102,7 @@ obj-y += mtd/
obj-y += pwm/
obj-y += reset/
obj-y += input/
+obj-y += iommu/
# SOC specific infrastructure drivers.
obj-y += smem/
obj-y += thermal/
@@ -28,6 +28,7 @@
#include <dm/uclass.h>
#include <dm/uclass-internal.h>
#include <dm/util.h>
+#include <iommu.h>
#include <linux/err.h>
#include <linux/list.h>
#include <power-domain.h>
@@ -543,6 +544,13 @@ int device_probe(struct udevice *dev)
goto fail;
}
+ if (CONFIG_IS_ENABLED(IOMMU) && dev->parent &&
+ (device_get_uclass_id(dev) != UCLASS_IOMMU)) {
+ ret = dev_iommu_probe(dev);
+ if (ret)
+ goto fail;
+ }
+
ret = device_get_dma_constraints(dev);
if (ret)
goto fail;
new file mode 100644
@@ -0,0 +1,13 @@
+#
+# IOMMU devices
+#
+
+menu "IOMMU device drivers"
+
+config IOMMU
+ bool "Enable Driver Model for IOMMU drivers"
+ depends on DM
+ help
+ Enable driver model for IOMMU devices.
+
+endmenu
new file mode 100644
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0+
+
+obj-$(CONFIG_IOMMU) += iommu-uclass.o
new file mode 100644
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2021 Mark Kettenis <kettenis@openbsd.org>
+ */
+
+#define LOG_CATEGORY UCLASS_IOMMU
+
+#include <common.h>
+#include <dm.h>
+
+#if (CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA))
+int dev_iommu_probe(struct udevice *dev)
+{
+ struct ofnode_phandle_args args;
+ struct udevice *dev_iommu;
+ int i, count, ret = 0;
+
+ count = dev_count_phandle_with_args(dev, "iommus",
+ "#iommu-cells", 0);
+ for (i = 0; i < count; i++) {
+ ret = dev_read_phandle_with_args(dev, "iommus",
+ "#iommu-cells", 0, i, &args);
+ if (ret) {
+ debug("%s: dev_read_phandle_with_args failed: %d\n",
+ __func__, ret);
+ return ret;
+ }
+
+ ret = uclass_get_device_by_ofnode(UCLASS_IOMMU, args.node,
+ &dev_iommu);
+ if (ret) {
+ debug("%s: uclass_get_device_by_ofnode failed: %d\n",
+ __func__, ret);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+#endif
+
+UCLASS_DRIVER(iommu) = {
+ .id = UCLASS_IOMMU,
+ .name = "iommu",
+};
@@ -62,6 +62,7 @@ enum uclass_id {
UCLASS_I2C_MUX, /* I2C multiplexer */
UCLASS_I2S, /* I2S bus */
UCLASS_IDE, /* IDE device */
+ UCLASS_IOMMU, /* IOMMU */
UCLASS_IRQ, /* Interrupt controller */
UCLASS_KEYBOARD, /* Keyboard input device */
UCLASS_LED, /* Light-emitting diode (LED) */
new file mode 100644
@@ -0,0 +1,16 @@
+#ifndef _IOMMU_H
+#define _IOMMU_H
+
+struct udevice;
+
+#if (CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)) && \
+ CONFIG_IS_ENABLED(IOMMU)
+int dev_iommu_probe(struct udevice *dev);
+#else
+static inline int dev_iommu_probe(struct udevice *dev)
+{
+ return 0;
+}
+#endif
+
+#endif
This uclass is intended to manage IOMMUs on systems where the IOMMUs are not in bypass mode by default. In that case U-Boot cannot ignore the IOMMUs if it wants to use devices that need to do DMA and sit behind such an IOMMU. This initial IOMMU uclass implementation does not implement and device ops and is intended for IOMMUs that have a bypass mode that does not require address translation. Support for IOMMUs that do require address translation is planned and device ops will be defined when support for such IOMMUs will be added. Signed-off-by: Mark Kettenis <kettenis@openbsd.org> --- drivers/Kconfig | 2 ++ drivers/Makefile | 1 + drivers/core/device.c | 8 +++++++ drivers/iommu/Kconfig | 13 +++++++++++ drivers/iommu/Makefile | 3 +++ drivers/iommu/iommu-uclass.c | 45 ++++++++++++++++++++++++++++++++++++ include/dm/uclass-id.h | 1 + include/iommu.h | 16 +++++++++++++ 8 files changed, 89 insertions(+) create mode 100644 drivers/iommu/Kconfig create mode 100644 drivers/iommu/Makefile create mode 100644 drivers/iommu/iommu-uclass.c create mode 100644 include/iommu.h