bus: mvebu: add mbus driver

This imports the Marvell mbus driver from Linux. The mbus is the
main downstream bus found on all Marvell Orion SoCs. The driver
deals with re-configurable address windows which are currently
parsed from DT. Also enable the driver as default on all MVEBU
SoCs. While at it, also reorder drivers/bus/{Kconfig,Makefile}
alphabetically.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

3 files changed, 757 insertions, 6 deletions

diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
index b0d3c1fe9d..202df59762 100644
--- a/drivers/bus/Kconfig
+++ b/drivers/bus/Kconfig
@@ -1,13 +1,20 @@
 menu "Bus devices"
 
-config IMX_WEIM
-	depends on ARCH_IMX
-	bool "i.MX WEIM driver"
-
 config BUS_OMAP_GPMC
 	depends on ARCH_OMAP
 	depends on OFDEVICE
 	depends on OMAP_GPMC
 	bool "TI OMAP/AM33xx GPMC support"
 
+config IMX_WEIM
+	depends on ARCH_IMX
+	bool "i.MX WEIM driver"
+
+config MVEBU_MBUS
+	bool
+	depends on ARCH_MVEBU
+	help
+	  Driver needed for the MBus configuration on Marvell EBU SoCs
+	  (Kirkwood, Dove, Orion5x, MV78XX0 and Armada 370/XP).
+
 endmenu
diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile
index f1c5ac73ca..4b7aa888ab 100644
--- a/drivers/bus/Makefile
+++ b/drivers/bus/Makefile
@@ -1,2 +1,3 @@
-obj-$(CONFIG_IMX_WEIM) += imx-weim.o
-obj-$(CONFIG_BUS_OMAP_GPMC) += omap-gpmc.o
+obj-$(CONFIG_BUS_OMAP_GPMC)	+= omap-gpmc.o
+obj-$(CONFIG_IMX_WEIM)		+= imx-weim.o
+obj-$(CONFIG_MVEBU_MBUS)	+= mvebu-mbus.o
diff --git a/drivers/bus/mvebu-mbus.c b/drivers/bus/mvebu-mbus.c
new file mode 100644
index 0000000000..11e3777a60
--- /dev/null
+++ b/drivers/bus/mvebu-mbus.c
@@ -0,0 +1,743 @@
+/*
+ * Address map functions for Marvell EBU SoCs (Kirkwood, Armada
+ * 370/XP, Dove, Orion5x and MV78xx0)
+ *
+ * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
+ *
+ * based on mbus driver from Linux
+ *   (C) Copyright 2008 Marvell Semiconductor
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ *
+ * The Marvell EBU SoCs have a configurable physical address space:
+ * the physical address at which certain devices (PCIe, NOR, NAND,
+ * etc.) sit can be configured. The configuration takes place through
+ * two sets of registers:
+ *
+ * - One to configure the access of the CPU to the devices. Depending
+ *   on the families, there are between 8 and 20 configurable windows,
+ *   each can be use to create a physical memory window that maps to a
+ *   specific device. Devices are identified by a tuple (target,
+ *   attribute).
+ *
+ * - One to configure the access to the CPU to the SDRAM. There are
+ *   either 2 (for Dove) or 4 (for other families) windows to map the
+ *   SDRAM into the physical address space.
+ *
+ * This driver:
+ *
+ * - Reads out the SDRAM address decoding windows at initialization
+ *   time, and fills the mbus_dram_info structure with these
+ *   informations. The exported function mv_mbus_dram_info() allow
+ *   device drivers to get those informations related to the SDRAM
+ *   address decoding windows. This is because devices also have their
+ *   own windows (configured through registers that are part of each
+ *   device register space), and therefore the drivers for Marvell
+ *   devices have to configure those device -> SDRAM windows to ensure
+ *   that DMA works properly.
+ *
+ * - Provides an API for platform code or device drivers to
+ *   dynamically add or remove address decoding windows for the CPU ->
+ *   device accesses. This API is mvebu_mbus_add_window_by_id(),
+ *   mvebu_mbus_add_window_remap_by_id() and
+ *   mvebu_mbus_del_window().
+ *
+ * - Provides a debugfs interface in /sys/kernel/debug/mvebu-mbus/ to
+ *   see the list of CPU -> SDRAM windows and their configuration
+ *   (file 'sdram') and the list of CPU -> devices windows and their
+ *   configuration (file 'devices').
+ */
+
+#include <common.h>
+#include <init.h>
+#include <io.h>
+#include <of.h>
+#include <of_address.h>
+#include <linux/mbus.h>
+
+/* DDR target is the same on all platforms */
+#define TARGET_DDR		0
+
+/* CPU Address Decode Windows registers */
+#define WIN_CTRL_OFF		0x0000
+#define   WIN_CTRL_ENABLE       BIT(0)
+#define   WIN_CTRL_TGT_MASK     0xf0
+#define   WIN_CTRL_TGT_SHIFT    4
+#define   WIN_CTRL_ATTR_MASK    0xff00
+#define   WIN_CTRL_ATTR_SHIFT   8
+#define   WIN_CTRL_SIZE_MASK    0xffff0000
+#define   WIN_CTRL_SIZE_SHIFT   16
+#define WIN_BASE_OFF		0x0004
+#define   WIN_BASE_LOW          0xffff0000
+#define   WIN_BASE_HIGH         0xf
+#define WIN_REMAP_LO_OFF	0x0008
+#define   WIN_REMAP_LOW         0xffff0000
+#define WIN_REMAP_HI_OFF	0x000c
+
+#define ATTR_HW_COHERENCY	(0x1 << 4)
+
+#define DDR_BASE_CS_OFF(n)	(0x0000 + ((n) << 3))
+#define  DDR_BASE_CS_HIGH_MASK  0xf
+#define  DDR_BASE_CS_LOW_MASK   0xff000000
+#define DDR_SIZE_CS_OFF(n)	(0x0004 + ((n) << 3))
+#define  DDR_SIZE_ENABLED       BIT(0)
+#define  DDR_SIZE_CS_MASK       0x1c
+#define  DDR_SIZE_CS_SHIFT      2
+#define  DDR_SIZE_MASK          0xff000000
+
+#define DOVE_DDR_BASE_CS_OFF(n) ((n) << 4)
+
+struct mvebu_mbus_state;
+
+struct mvebu_mbus_soc_data {
+	unsigned int num_wins;
+	unsigned int num_remappable_wins;
+	unsigned int (*win_cfg_offset)(const int win);
+	void (*setup_cpu_target)(struct mvebu_mbus_state *s);
+};
+
+struct mvebu_mbus_state {
+	struct device_d *dev;
+	void __iomem *mbuswins_base;
+	void __iomem *sdramwins_base;
+	struct dentry *debugfs_root;
+	struct dentry *debugfs_sdram;
+	struct dentry *debugfs_devs;
+	struct resource pcie_mem_aperture;
+	struct resource pcie_io_aperture;
+	const struct mvebu_mbus_soc_data *soc;
+	int hw_io_coherency;
+};
+
+static struct mvebu_mbus_state mbus_state;
+static struct mbus_dram_target_info mbus_dram_info;
+
+/*
+ * Functions to manipulate the address decoding windows
+ */
+
+static void mvebu_mbus_read_window(struct mvebu_mbus_state *mbus,
+				   int win, int *enabled, u64 *base,
+				   u32 *size, u8 *target, u8 *attr,
+				   u64 *remap)
+{
+	void __iomem *addr = mbus->mbuswins_base +
+		mbus->soc->win_cfg_offset(win);
+	u32 basereg = readl(addr + WIN_BASE_OFF);
+	u32 ctrlreg = readl(addr + WIN_CTRL_OFF);
+
+	if (!(ctrlreg & WIN_CTRL_ENABLE)) {
+		*enabled = 0;
+		return;
+	}
+
+	*enabled = 1;
+	*base = ((u64)basereg & WIN_BASE_HIGH) << 32;
+	*base |= (basereg & WIN_BASE_LOW);
+	*size = (ctrlreg | ~WIN_CTRL_SIZE_MASK) + 1;
+
+	if (target)
+		*target = (ctrlreg & WIN_CTRL_TGT_MASK) >> WIN_CTRL_TGT_SHIFT;
+
+	if (attr)
+		*attr = (ctrlreg & WIN_CTRL_ATTR_MASK) >> WIN_CTRL_ATTR_SHIFT;
+
+	if (remap) {
+		if (win < mbus->soc->num_remappable_wins) {
+			u32 remap_low = readl(addr + WIN_REMAP_LO_OFF);
+			u32 remap_hi  = readl(addr + WIN_REMAP_HI_OFF);
+			*remap = ((u64)remap_hi << 32) | remap_low;
+		} else
+			*remap = 0;
+	}
+}
+
+static void mvebu_mbus_disable_window(struct mvebu_mbus_state *mbus,
+				      int win)
+{
+	void __iomem *addr;
+
+	addr = mbus->mbuswins_base + mbus->soc->win_cfg_offset(win);
+
+	writel(0, addr + WIN_BASE_OFF);
+	writel(0, addr + WIN_CTRL_OFF);
+	if (win < mbus->soc->num_remappable_wins) {
+		writel(0, addr + WIN_REMAP_LO_OFF);
+		writel(0, addr + WIN_REMAP_HI_OFF);
+	}
+}
+
+/* Checks whether the given window number is available */
+static int mvebu_mbus_window_is_free(struct mvebu_mbus_state *mbus,
+				     const int win)
+{
+	void __iomem *addr = mbus->mbuswins_base +
+		mbus->soc->win_cfg_offset(win);
+	u32 ctrl = readl(addr + WIN_CTRL_OFF);
+	return !(ctrl & WIN_CTRL_ENABLE);
+}
+
+/*
+ * Checks whether the given (base, base+size) area doesn't overlap an
+ * existing region
+ */
+static int mvebu_mbus_window_conflicts(struct mvebu_mbus_state *mbus,
+				       phys_addr_t base, size_t size,
+				       u8 target, u8 attr)
+{
+	u64 end = (u64)base + size;
+	int win;
+
+	for (win = 0; win < mbus->soc->num_wins; win++) {
+		u64 wbase, wend;
+		u32 wsize;
+		u8 wtarget, wattr;
+		int enabled;
+
+		mvebu_mbus_read_window(mbus, win,
+				       &enabled, &wbase, &wsize,
+				       &wtarget, &wattr, NULL);
+
+		if (!enabled)
+			continue;
+
+		wend = wbase + wsize;
+
+		/*
+		 * Check if the current window overlaps with the
+		 * proposed physical range
+		 */
+		if ((u64)base < wend && end > wbase)
+			return 0;
+
+		/*
+		 * Check if target/attribute conflicts
+		 */
+		if (target == wtarget && attr == wattr)
+			return 0;
+	}
+
+	return 1;
+}
+
+static int mvebu_mbus_find_window(struct mvebu_mbus_state *mbus,
+				  phys_addr_t base, size_t size)
+{
+	int win;
+
+	for (win = 0; win < mbus->soc->num_wins; win++) {
+		u64 wbase;
+		u32 wsize;
+		int enabled;
+
+		mvebu_mbus_read_window(mbus, win,
+				       &enabled, &wbase, &wsize,
+				       NULL, NULL, NULL);
+
+		if (!enabled)
+			continue;
+
+		if (base == wbase && size == wsize)
+			return win;
+	}
+
+	return -ENODEV;
+}
+
+static int mvebu_mbus_setup_window(struct mvebu_mbus_state *mbus,
+				   int win, phys_addr_t base, size_t size,
+				   phys_addr_t remap, u8 target,
+				   u8 attr)
+{
+	void __iomem *addr = mbus->mbuswins_base +
+		mbus->soc->win_cfg_offset(win);
+	u32 ctrl, remap_addr;
+
+	ctrl = ((size - 1) & WIN_CTRL_SIZE_MASK) |
+		(attr << WIN_CTRL_ATTR_SHIFT)    |
+		(target << WIN_CTRL_TGT_SHIFT)   |
+		WIN_CTRL_ENABLE;
+
+	writel(base & WIN_BASE_LOW, addr + WIN_BASE_OFF);
+	writel(ctrl, addr + WIN_CTRL_OFF);
+	if (win < mbus->soc->num_remappable_wins) {
+		if (remap == MVEBU_MBUS_NO_REMAP)
+			remap_addr = base;
+		else
+			remap_addr = remap;
+		writel(remap_addr & WIN_REMAP_LOW, addr + WIN_REMAP_LO_OFF);
+		writel(0, addr + WIN_REMAP_HI_OFF);
+	}
+
+	return 0;
+}
+
+static int mvebu_mbus_alloc_window(struct mvebu_mbus_state *mbus,
+				   phys_addr_t base, size_t size,
+				   phys_addr_t remap, u8 target,
+				   u8 attr)
+{
+	int win;
+
+	if (remap == MVEBU_MBUS_NO_REMAP) {
+		for (win = mbus->soc->num_remappable_wins;
+		     win < mbus->soc->num_wins; win++)
+			if (mvebu_mbus_window_is_free(mbus, win))
+				return mvebu_mbus_setup_window(mbus, win, base,
+							       size, remap,
+							       target, attr);
+	}
+
+
+	for (win = 0; win < mbus->soc->num_wins; win++)
+		if (mvebu_mbus_window_is_free(mbus, win))
+			return mvebu_mbus_setup_window(mbus, win, base, size,
+						       remap, target, attr);
+
+	return -ENOMEM;
+}
+
+/*
+ * SoC-specific functions and definitions
+ */
+
+static unsigned int armada_370_xp_mbus_win_offset(int win)
+{
+	/* The register layout is a bit annoying and the below code
+	 * tries to cope with it.
+	 * - At offset 0x0, there are the registers for the first 8
+	 *   windows, with 4 registers of 32 bits per window (ctrl,
+	 *   base, remap low, remap high)
+	 * - Then at offset 0x80, there is a hole of 0x10 bytes for
+	 *   the internal registers base address and internal units
+	 *   sync barrier register.
+	 * - Then at offset 0x90, there the registers for 12
+	 *   windows, with only 2 registers of 32 bits per window
+	 *   (ctrl, base).
+	 */
+	if (win < 8)
+		return win << 4;
+	else
+		return 0x90 + ((win - 8) << 3);
+}
+
+static unsigned int orion5x_mbus_win_offset(int win)
+{
+	return win << 4;
+}
+
+static unsigned int mv78xx0_mbus_win_offset(int win)
+{
+	if (win < 8)
+		return win << 4;
+	else
+		return 0x900 + ((win - 8) << 4);
+}
+
+static void mvebu_mbus_default_setup_cpu_target(struct mvebu_mbus_state *mbus)
+{
+	int i;
+	int cs;
+
+	mbus_dram_info.mbus_dram_target_id = TARGET_DDR;
+
+	for (i = 0, cs = 0; i < 4; i++) {
+		u32 base = readl(mbus->sdramwins_base + DDR_BASE_CS_OFF(i));
+		u32 size = readl(mbus->sdramwins_base + DDR_SIZE_CS_OFF(i));
+
+		/*
+		 * We only take care of entries for which the chip
+		 * select is enabled, and that don't have high base
+		 * address bits set (devices can only access the first
+		 * 32 bits of the memory).
+		 */
+		if ((size & DDR_SIZE_ENABLED) &&
+		    !(base & DDR_BASE_CS_HIGH_MASK)) {
+			struct mbus_dram_window *w;
+
+			w = &mbus_dram_info.cs[cs++];
+			w->cs_index = i;
+			w->mbus_attr = 0xf & ~(1 << i);
+			if (mbus->hw_io_coherency)
+				w->mbus_attr |= ATTR_HW_COHERENCY;
+			w->base = base & DDR_BASE_CS_LOW_MASK;
+			w->size = (size | ~DDR_SIZE_MASK) + 1;
+		}
+	}
+	mbus_dram_info.num_cs = cs;
+}
+
+static void mvebu_mbus_dove_setup_cpu_target(struct mvebu_mbus_state *mbus)
+{
+	int i;
+	int cs;
+
+	mbus_dram_info.mbus_dram_target_id = TARGET_DDR;
+
+	for (i = 0, cs = 0; i < 2; i++) {
+		u32 map = readl(mbus->sdramwins_base + DOVE_DDR_BASE_CS_OFF(i));
+
+		/*
+		 * Chip select enabled?
+		 */
+		if (map & 1) {
+			struct mbus_dram_window *w;
+
+			w = &mbus_dram_info.cs[cs++];
+			w->cs_index = i;
+			w->mbus_attr = 0; /* CS address decoding done inside */
+					  /* the DDR controller, no need to  */
+					  /* provide attributes */
+			w->base = map & 0xff800000;
+			w->size = 0x100000 << (((map & 0x000f0000) >> 16) - 4);
+		}
+	}
+
+	mbus_dram_info.num_cs = cs;
+}
+
+static const struct mvebu_mbus_soc_data
+armada_370_xp_mbus_data __maybe_unused = {
+	.num_wins            = 20,
+	.num_remappable_wins = 8,
+	.win_cfg_offset      = armada_370_xp_mbus_win_offset,
+	.setup_cpu_target    = mvebu_mbus_default_setup_cpu_target,
+};
+
+static const struct mvebu_mbus_soc_data
+dove_mbus_data __maybe_unused = {
+	.num_wins            = 8,
+	.num_remappable_wins = 4,
+	.win_cfg_offset      = orion5x_mbus_win_offset,
+	.setup_cpu_target    = mvebu_mbus_dove_setup_cpu_target,
+};
+
+static const struct mvebu_mbus_soc_data
+kirkwood_mbus_data __maybe_unused = {
+	.num_wins            = 8,
+	.num_remappable_wins = 4,
+	.win_cfg_offset      = orion5x_mbus_win_offset,
+	.setup_cpu_target    = mvebu_mbus_default_setup_cpu_target,
+};
+
+/*
+ * Some variants of Orion5x have 4 remappable windows, some other have
+ * only two of them.
+ */
+static const struct mvebu_mbus_soc_data
+orion5x_4win_mbus_data __maybe_unused = {
+	.num_wins            = 8,
+	.num_remappable_wins = 4,
+	.win_cfg_offset      = orion5x_mbus_win_offset,
+	.setup_cpu_target    = mvebu_mbus_default_setup_cpu_target,
+};
+
+static const struct mvebu_mbus_soc_data
+orion5x_2win_mbus_data__maybe_unused = {
+	.num_wins            = 8,
+	.num_remappable_wins = 2,
+	.win_cfg_offset      = orion5x_mbus_win_offset,
+	.setup_cpu_target    = mvebu_mbus_default_setup_cpu_target,
+};
+
+static const struct mvebu_mbus_soc_data
+mv78xx0_mbus_data __maybe_unused = {
+	.num_wins            = 14,
+	.num_remappable_wins = 8,
+	.win_cfg_offset      = mv78xx0_mbus_win_offset,
+	.setup_cpu_target    = mvebu_mbus_default_setup_cpu_target,
+};
+
+static struct of_device_id mvebu_mbus_dt_ids[] = {
+#if defined(CONFIG_ARCH_ARMADA_370) || defined(CONFIG_ARCH_ARMADA_XP)
+	{ .compatible = "marvell,armada370-mbus",
+	  .data = (u32)&armada_370_xp_mbus_data, },
+	{ .compatible = "marvell,armadaxp-mbus",
+	  .data = (u32)&armada_370_xp_mbus_data, },
+#endif
+#if defined(CONFIG_ARCH_DOVE)
+	{ .compatible = "marvell,dove-mbus",
+	  .data = (u32)&dove_mbus_data, },
+#endif
+#if defined(CONFIG_ARCH_KIRKWOOD)
+	{ .compatible = "marvell,kirkwood-mbus",
+	  .data = (u32)&kirkwood_mbus_data, },
+#endif
+#if defined(CONFIG_ARCH_ORION5X)
+	{ .compatible = "marvell,orion5x-88f5281-mbus",
+	  .data = (u32)&orion5x_4win_mbus_data, },
+	{ .compatible = "marvell,orion5x-88f5182-mbus",
+	  .data = (u32)&orion5x_2win_mbus_data, },
+	{ .compatible = "marvell,orion5x-88f5181-mbus",
+	  .data = (u32)&orion5x_2win_mbus_data, },
+	{ .compatible = "marvell,orion5x-88f6183-mbus",
+	  .data = (u32)&orion5x_4win_mbus_data, },
+#endif
+#if defined(CONFIG_ARCH_MV78XX0)
+	{ .compatible = "marvell,mv78xx0-mbus",
+	  .data = (u32)&mv78xx0_mbus_data, },
+#endif
+	{ },
+};
+
+/*
+ * Public API of the driver
+ */
+const struct mbus_dram_target_info *mvebu_mbus_dram_info(void)
+{
+	return &mbus_dram_info;
+}
+
+int mvebu_mbus_add_window_remap_by_id(unsigned int target,
+				      unsigned int attribute,
+				      phys_addr_t base, size_t size,
+				      phys_addr_t remap)
+{
+	struct mvebu_mbus_state *s = &mbus_state;
+
+	if (!mvebu_mbus_window_conflicts(s, base, size, target, attribute)) {
+		dev_err(s->dev, "cannot add window '%x:%x', conflicts with another window\n",
+		       target, attribute);
+		return -EINVAL;
+	}
+
+	return mvebu_mbus_alloc_window(s, base, size, remap, target, attribute);
+}
+
+int mvebu_mbus_add_window_by_id(unsigned int target, unsigned int attribute,
+				phys_addr_t base, size_t size)
+{
+	return mvebu_mbus_add_window_remap_by_id(target, attribute, base,
+						 size, MVEBU_MBUS_NO_REMAP);
+}
+
+int mvebu_mbus_del_window(phys_addr_t base, size_t size)
+{
+	int win;
+
+	win = mvebu_mbus_find_window(&mbus_state, base, size);
+	if (win < 0)
+		return win;
+
+	mvebu_mbus_disable_window(&mbus_state, win);
+	return 0;
+}
+
+void mvebu_mbus_get_pcie_mem_aperture(struct resource *res)
+{
+	if (!res)
+		return;
+	*res = mbus_state.pcie_mem_aperture;
+}
+
+void mvebu_mbus_get_pcie_io_aperture(struct resource *res)
+{
+	if (!res)
+		return;
+	*res = mbus_state.pcie_io_aperture;
+}
+
+/*
+ * The window IDs in the ranges DT property have the following format:
+ *  - bits 28 to 31: MBus custom field
+ *  - bits 24 to 27: window target ID
+ *  - bits 16 to 23: window attribute ID
+ *  - bits  0 to 15: unused
+ */
+#define CUSTOM(id) (((id) & 0xF0000000) >> 24)
+#define TARGET(id) (((id) & 0x0F000000) >> 24)
+#define ATTR(id)   (((id) & 0x00FF0000) >> 16)
+
+static int mbus_dt_setup_win(struct mvebu_mbus_state *mbus,
+			     u32 base, u32 size, u8 target, u8 attr)
+{
+	if (!mvebu_mbus_window_conflicts(mbus, base, size, target, attr)) {
+		dev_err(mbus->dev, "cannot add window '%04x:%04x', conflicts with another window\n",
+		       target, attr);
+		return -EBUSY;
+	}
+
+	if (mvebu_mbus_alloc_window(mbus, base, size, MVEBU_MBUS_NO_REMAP,
+				    target, attr)) {
+		dev_err(mbus->dev, "cannot add window '%04x:%04x', too many windows\n",
+		       target, attr);
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+static int mbus_parse_ranges(struct mvebu_mbus_state *mbus, int *addr_cells,
+			     int *c_addr_cells, int *c_size_cells,
+			     int *cell_count, const __be32 **ranges_start,
+			     const __be32 **ranges_end)
+{
+	struct device_node *node = mbus->dev->device_node;
+	const __be32 *prop;
+	int ranges_len, tuple_len;
+
+	/* Allow a node with no 'ranges' property */
+	*ranges_start = of_get_property(node, "ranges", &ranges_len);
+	if (*ranges_start == NULL) {
+		*addr_cells = *c_addr_cells = *c_size_cells = *cell_count = 0;
+		*ranges_start = *ranges_end = NULL;
+		return 0;
+	}
+	*ranges_end = *ranges_start + ranges_len / sizeof(__be32);
+
+	*addr_cells = of_n_addr_cells(node);
+
+	prop = of_get_property(node, "#address-cells", NULL);
+	*c_addr_cells = be32_to_cpup(prop);
+
+	prop = of_get_property(node, "#size-cells", NULL);
+	*c_size_cells = be32_to_cpup(prop);
+
+	*cell_count = *addr_cells + *c_addr_cells + *c_size_cells;
+	tuple_len = (*cell_count) * sizeof(__be32);
+
+	if (ranges_len % tuple_len) {
+		dev_warn(mbus->dev, "malformed ranges entry '%s'\n",
+			node->name);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int mbus_dt_setup(struct mvebu_mbus_state *mbus)
+{
+	int addr_cells, c_addr_cells, c_size_cells;
+	int i, ret, cell_count;
+	const __be32 *r, *ranges_start, *ranges_end;
+
+	ret = mbus_parse_ranges(mbus, &addr_cells, &c_addr_cells,
+				&c_size_cells, &cell_count,
+				&ranges_start, &ranges_end);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0, r = ranges_start; r < ranges_end; r += cell_count, i++) {
+		u32 windowid, base, size;
+		u8 target, attr;
+
+		/*
+		 * An entry with a non-zero custom field do not
+		 * correspond to a static window, so skip it.
+		 */
+		windowid = of_read_number(r, 1);
+		if (CUSTOM(windowid))
+			continue;
+
+		target = TARGET(windowid);
+		attr = ATTR(windowid);
+
+		base = of_read_number(r + c_addr_cells, addr_cells);
+		size = of_read_number(r + c_addr_cells + addr_cells,
+				      c_size_cells);
+		ret = mbus_dt_setup_win(mbus, base, size, target, attr);
+		if (ret < 0)
+			return ret;
+	}
+	return 0;
+}
+
+static void mvebu_mbus_get_pcie_resources(struct device_node *np,
+			  struct resource *mem, struct resource *io)
+{
+	u32 reg[2];
+	int ret;
+
+	/*
+	 * These are optional, so we make sure that resource_size(x) will
+	 * return 0.
+	 */
+	memset(mem, 0, sizeof(struct resource));
+	mem->end = -1;
+	memset(io, 0, sizeof(struct resource));
+	io->end = -1;
+
+	ret = of_property_read_u32_array(np, "pcie-mem-aperture",
+					 reg, ARRAY_SIZE(reg));
+	if (!ret) {
+		mem->start = reg[0];
+		mem->end = mem->start + reg[1];
+		mem->flags = IORESOURCE_MEM;
+	}
+
+	ret = of_property_read_u32_array(np, "pcie-io-aperture",
+					 reg, ARRAY_SIZE(reg));
+	if (!ret) {
+		io->start = reg[0];
+		io->end = io->start + reg[1];
+		io->flags = IORESOURCE_IO;
+	}
+}
+
+static int mvebu_mbus_probe(struct device_d *dev)
+{
+	struct device_node *np, *controller;
+	const struct of_device_id *match;
+	const __be32 *prop;
+	int win;
+
+	mbus_state.dev = dev;
+
+	np = of_find_matching_node_and_match(NULL, mvebu_mbus_dt_ids, &match);
+	if (!np) {
+		dev_err(dev, "could not find a matching SoC family\n");
+		return -ENODEV;
+	}
+	mbus_state.soc = (struct mvebu_mbus_soc_data *)match->data;
+
+	prop = of_get_property(np, "controller", NULL);
+	if (!prop) {
+		dev_err(dev, "required 'controller' property missing\n");
+		return -EINVAL;
+	}
+
+	controller = of_find_node_by_phandle(be32_to_cpup(prop));
+	if (!controller) {
+		dev_err(dev, "could not find an 'mbus-controller' node\n");
+		return -ENODEV;
+	}
+
+	mbus_state.mbuswins_base = of_iomap(controller, 0);
+	if (!mbus_state.mbuswins_base) {
+		dev_err(dev, "cannot get MBUS register address\n");
+		return -ENOMEM;
+	}
+
+	mbus_state.sdramwins_base = of_iomap(controller, 1);
+	if (!mbus_state.sdramwins_base) {
+		dev_err(dev, "cannot get SDRAM register address\n");
+		return -ENOMEM;
+	}
+
+	/* Get optional pcie-{mem,io}-aperture properties */
+	mvebu_mbus_get_pcie_resources(np, &mbus_state.pcie_mem_aperture,
+					  &mbus_state.pcie_io_aperture);
+
+	if (of_find_compatible_node(NULL, NULL, "marvell,coherency-fabric"))
+		mbus_state.hw_io_coherency = 1;
+
+	for (win = 0; win < mbus_state.soc->num_wins; win++)
+		mvebu_mbus_disable_window(&mbus_state, win);
+
+	mbus_state.soc->setup_cpu_target(&mbus_state);
+
+	/* Setup statically declared windows in the DT */
+	return mbus_dt_setup(&mbus_state);
+}
+
+static struct driver_d mvebu_mbus_driver = {
+	.probe	= mvebu_mbus_probe,
+	.name	= "mvebu-mbus",
+	.of_compatible = DRV_OF_COMPAT(mvebu_mbus_dt_ids),
+};
+
+static int mvebu_mbus_init(void)
+{
+	return platform_driver_register(&mvebu_mbus_driver);
+}
+postcore_initcall(mvebu_mbus_init);