drivers: Add AXI uclass

Add a uclass for AXI (Advanced eXtensible Interface) busses, and a
driver for the gdsys IHS AXI bus on IHS FPGAs.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Reviewed-by: Simon Glass <sjg@chromium.org>

diff --git a/drivers/Kconfig b/drivers/Kconfig
index c72abf893297094cc7a143a613ad914d535c99af..56536c4b19150e325e2494f36078f859959d42c4 100644 (file)
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -8,6 +8,8 @@ source "drivers/adc/Kconfig"
 
 source "drivers/ata/Kconfig"
 
+source "drivers/axi/Kconfig"
+
 source "drivers/block/Kconfig"
 
 source "drivers/bootcount/Kconfig"

diff --git a/drivers/Makefile b/drivers/Makefile
index d53208540ea61e5620b4adae9191737c009364d0..d296354b3c01e49f3a7949305c99dc03c7ca1302 100644 (file)
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -103,6 +103,7 @@ obj-y += smem/
 obj-y += soc/
 obj-$(CONFIG_REMOTEPROC) += remoteproc/
 obj-y += thermal/
+obj-y += axi/
 
 obj-$(CONFIG_MACH_PIC32) += ddr/microchip/
 endif

diff --git a/drivers/axi/Kconfig b/drivers/axi/Kconfig
new file mode 100644 (file)
index 0000000..4e4153b
--- /dev/null
+++ b/drivers/axi/Kconfig
@@ -0,0 +1,13 @@
+menuconfig AXI
+       bool "AXI bus drivers"
+       help
+         Support AXI (Advanced eXtensible Interface) busses, a on-chip
+         interconnect specification for managing functional blocks in SoC
+         designs, which is also often used in designs involving FPGAs (e.g.
+         communication with IP cores in Xilinx FPGAs).
+
+         These types of busses expose a virtual address space that can be
+         accessed using different address widths (8, 16, and 32 are supported
+         for now).
+
+         Other similar bus architectures may be compatible as well.

diff --git a/drivers/axi/Makefile b/drivers/axi/Makefile
new file mode 100644 (file)
index 0000000..100a777
--- /dev/null
+++ b/drivers/axi/Makefile
@@ -0,0 +1,8 @@
+#
+# (C) Copyright 2017
+# Mario Six,  Guntermann & Drunck GmbH, mario.six@gdsys.cc
+#
+# SPDX-License-Identifier:     GPL-2.0+
+#
+
+obj-$(CONFIG_AXI) += axi-uclass.o

diff --git a/drivers/axi/axi-uclass.c b/drivers/axi/axi-uclass.c
new file mode 100644 (file)
index 0000000..af8acd9
--- /dev/null
+++ b/drivers/axi/axi-uclass.c
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2017
+ * Mario Six,  Guntermann & Drunck GmbH, mario.six@gdsys.cc
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <axi.h>
+
+int axi_read(struct udevice *dev, ulong address, void *data,
+            enum axi_size_t size)
+{
+       struct axi_ops *ops = axi_get_ops(dev);
+
+       if (!ops->read)
+               return -ENOSYS;
+
+       return ops->read(dev, address, data, size);
+}
+
+int axi_write(struct udevice *dev, ulong address, void *data,
+             enum axi_size_t size)
+{
+       struct axi_ops *ops = axi_get_ops(dev);
+
+       if (!ops->write)
+               return -ENOSYS;
+
+       return ops->write(dev, address, data, size);
+}
+
+UCLASS_DRIVER(axi) = {
+       .id             = UCLASS_AXI,
+       .name           = "axi",
+       .post_bind      = dm_scan_fdt_dev,
+       .flags          = DM_UC_FLAG_SEQ_ALIAS,
+};
+

diff --git a/include/axi.h b/include/axi.h
new file mode 100644 (file)
index 0000000..2ff81c1
--- /dev/null
+++ b/include/axi.h
@@ -0,0 +1,78 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * (C) Copyright 2017
+ * Mario Six,  Guntermann & Drunck GmbH, mario.six@gdsys.cc
+ */
+
+#ifndef _AXI_H_
+#define _AXI_H_
+
+enum axi_size_t {
+       AXI_SIZE_8,
+       AXI_SIZE_16,
+       AXI_SIZE_32,
+};
+
+/**
+ * struct axi_ops - driver operations for AXI uclass
+ *
+ * Drivers should support these operations unless otherwise noted. These
+ * operations are intended to be used by uclass code, not directly from
+ * other code.
+ */
+struct axi_ops {
+       /**
+        * read() - Read a single value from a specified address on a AXI bus
+        *
+        * @dev:        AXI bus to read from.
+        * @address:    The address to read from.
+        * @data:       Pointer to a variable that takes the data value read
+        *              from the address on the AXI bus.
+        * @size:       The size of the data to be read.
+        * @return 0 if OK, -ve on error.
+        */
+       int (*read)(struct udevice *dev, ulong address, void *data,
+                   enum axi_size_t size);
+
+       /**
+        * write() - Write a single value to a specified address on a AXI bus
+        *
+        * @dev:        AXI bus to write to.
+        * @address:    The address to write to.
+        * @data:       Pointer to the data value to be written to the address
+        *              on the AXI bus.
+        * @size:       The size of the data to write.
+        * @return 0 if OK, -ve on error.
+        */
+       int (*write)(struct udevice *dev, ulong address, void *data,
+                    enum axi_size_t size);
+};
+
+#define axi_get_ops(dev)       ((struct axi_ops *)(dev)->driver->ops)
+
+/**
+ * axi_read() - Read a single value from a specified address on a AXI bus
+ *
+ * @dev:       AXI bus to read from.
+ * @address:   The address to read from.
+ * @data:      Pointer to a variable that takes the data value read from the
+ *              address on the AXI bus.
+ * @size:      The size of the data to write.
+ * @return 0 if OK, -ve on error.
+ */
+int axi_read(struct udevice *dev, ulong address, void *data,
+            enum axi_size_t size);
+
+/**
+ * axi_write() - Write a single value to a specified address on a AXI bus
+ *
+ * @dev:       AXI bus to write to.
+ * @address:   The address to write to.
+ * @data:      Pointer to the data value to be written to the address on the
+ *             AXI bus.
+ * @size:      The size of the data to write.
+ * @return 0 if OK, -ve on error.
+ */
+int axi_write(struct udevice *dev, ulong address, void *data,
+             enum axi_size_t size);
+#endif

diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index a39643ec5eefdb2bde5b3493dbc8feefb93fbb22..618f43ad45889f5a53c1f6281c2bb8a2433a9323 100644 (file)
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -43,6 +43,7 @@ enum uclass_id {
        UCLASS_I2C_GENERIC,     /* Generic I2C device */
        UCLASS_I2C_MUX,         /* I2C multiplexer */
        UCLASS_IDE,             /* IDE device */
+       UCLASS_AXI,             /* AXI bus */
        UCLASS_IRQ,             /* Interrupt controller */
        UCLASS_KEYBOARD,        /* Keyboard input device */
        UCLASS_LED,             /* Light-emitting diode (LED) */