Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 797 insertions, 0 deletions

diff --git a/drivers/misc/spear13xx_pcie_gadget.c b/drivers/misc/spear13xx_pcie_gadget.c
new file mode 100644
index 000000000..ee120dcbb
--- /dev/null
+++ b/drivers/misc/spear13xx_pcie_gadget.c
@@ -0,0 +1,797 @@
+/*
+ * drivers/misc/spear13xx_pcie_gadget.c
+ *
+ * Copyright (C) 2010 ST Microelectronics
+ * Pratyush Anand<pratyush.anand@gmail.com>
+ *
+ * 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.
+ */
+
+#include <linux/device.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pci_regs.h>
+#include <linux/configfs.h>
+#include <mach/pcie.h>
+#include <mach/misc_regs.h>
+
+#define IN0_MEM_SIZE	(200 * 1024 * 1024 - 1)
+/* In current implementation address translation is done using IN0 only.
+ * So IN1 start address and IN0 end address has been kept same
+*/
+#define IN1_MEM_SIZE	(0 * 1024 * 1024 - 1)
+#define IN_IO_SIZE	(20 * 1024 * 1024 - 1)
+#define IN_CFG0_SIZE	(12 * 1024 * 1024 - 1)
+#define IN_CFG1_SIZE	(12 * 1024 * 1024 - 1)
+#define IN_MSG_SIZE	(12 * 1024 * 1024 - 1)
+/* Keep default BAR size as 4K*/
+/* AORAM would be mapped by default*/
+#define INBOUND_ADDR_MASK	(SPEAR13XX_SYSRAM1_SIZE - 1)
+
+#define INT_TYPE_NO_INT	0
+#define INT_TYPE_INTX	1
+#define INT_TYPE_MSI	2
+struct spear_pcie_gadget_config {
+	void __iomem *base;
+	void __iomem *va_app_base;
+	void __iomem *va_dbi_base;
+	char int_type[10];
+	ulong requested_msi;
+	ulong configured_msi;
+	ulong bar0_size;
+	ulong bar0_rw_offset;
+	void __iomem *va_bar0_address;
+};
+
+struct pcie_gadget_target {
+	struct configfs_subsystem subsys;
+	struct spear_pcie_gadget_config config;
+};
+
+struct pcie_gadget_target_attr {
+	struct configfs_attribute	attr;
+	ssize_t		(*show)(struct spear_pcie_gadget_config *config,
+						char *buf);
+	ssize_t		(*store)(struct spear_pcie_gadget_config *config,
+						 const char *buf,
+						 size_t count);
+};
+
+static void enable_dbi_access(struct pcie_app_reg __iomem *app_reg)
+{
+	/* Enable DBI access */
+	writel(readl(&app_reg->slv_armisc) | (1 << AXI_OP_DBI_ACCESS_ID),
+			&app_reg->slv_armisc);
+	writel(readl(&app_reg->slv_awmisc) | (1 << AXI_OP_DBI_ACCESS_ID),
+			&app_reg->slv_awmisc);
+
+}
+
+static void disable_dbi_access(struct pcie_app_reg __iomem *app_reg)
+{
+	/* disable DBI access */
+	writel(readl(&app_reg->slv_armisc) & ~(1 << AXI_OP_DBI_ACCESS_ID),
+			&app_reg->slv_armisc);
+	writel(readl(&app_reg->slv_awmisc) & ~(1 << AXI_OP_DBI_ACCESS_ID),
+			&app_reg->slv_awmisc);
+
+}
+
+static void spear_dbi_read_reg(struct spear_pcie_gadget_config *config,
+		int where, int size, u32 *val)
+{
+	struct pcie_app_reg __iomem *app_reg = config->va_app_base;
+	ulong va_address;
+
+	/* Enable DBI access */
+	enable_dbi_access(app_reg);
+
+	va_address = (ulong)config->va_dbi_base + (where & ~0x3);
+
+	*val = readl(va_address);
+
+	if (size == 1)
+		*val = (*val >> (8 * (where & 3))) & 0xff;
+	else if (size == 2)
+		*val = (*val >> (8 * (where & 3))) & 0xffff;
+
+	/* Disable DBI access */
+	disable_dbi_access(app_reg);
+}
+
+static void spear_dbi_write_reg(struct spear_pcie_gadget_config *config,
+		int where, int size, u32 val)
+{
+	struct pcie_app_reg __iomem *app_reg = config->va_app_base;
+	ulong va_address;
+
+	/* Enable DBI access */
+	enable_dbi_access(app_reg);
+
+	va_address = (ulong)config->va_dbi_base + (where & ~0x3);
+
+	if (size == 4)
+		writel(val, va_address);
+	else if (size == 2)
+		writew(val, va_address + (where & 2));
+	else if (size == 1)
+		writeb(val, va_address + (where & 3));
+
+	/* Disable DBI access */
+	disable_dbi_access(app_reg);
+}
+
+#define PCI_FIND_CAP_TTL	48
+
+static int pci_find_own_next_cap_ttl(struct spear_pcie_gadget_config *config,
+		u32 pos, int cap, int *ttl)
+{
+	u32 id;
+
+	while ((*ttl)--) {
+		spear_dbi_read_reg(config, pos, 1, &pos);
+		if (pos < 0x40)
+			break;
+		pos &= ~3;
+		spear_dbi_read_reg(config, pos + PCI_CAP_LIST_ID, 1, &id);
+		if (id == 0xff)
+			break;
+		if (id == cap)
+			return pos;
+		pos += PCI_CAP_LIST_NEXT;
+	}
+	return 0;
+}
+
+static int pci_find_own_next_cap(struct spear_pcie_gadget_config *config,
+			u32 pos, int cap)
+{
+	int ttl = PCI_FIND_CAP_TTL;
+
+	return pci_find_own_next_cap_ttl(config, pos, cap, &ttl);
+}
+
+static int pci_find_own_cap_start(struct spear_pcie_gadget_config *config,
+				u8 hdr_type)
+{
+	u32 status;
+
+	spear_dbi_read_reg(config, PCI_STATUS, 2, &status);
+	if (!(status & PCI_STATUS_CAP_LIST))
+		return 0;
+
+	switch (hdr_type) {
+	case PCI_HEADER_TYPE_NORMAL:
+	case PCI_HEADER_TYPE_BRIDGE:
+		return PCI_CAPABILITY_LIST;
+	case PCI_HEADER_TYPE_CARDBUS:
+		return PCI_CB_CAPABILITY_LIST;
+	default:
+		return 0;
+	}
+
+	return 0;
+}
+
+/*
+ * Tell if a device supports a given PCI capability.
+ * Returns the address of the requested capability structure within the
+ * device's PCI configuration space or 0 in case the device does not
+ * support it. Possible values for @cap:
+ *
+ * %PCI_CAP_ID_PM	Power Management
+ * %PCI_CAP_ID_AGP	Accelerated Graphics Port
+ * %PCI_CAP_ID_VPD	Vital Product Data
+ * %PCI_CAP_ID_SLOTID	Slot Identification
+ * %PCI_CAP_ID_MSI	Message Signalled Interrupts
+ * %PCI_CAP_ID_CHSWP	CompactPCI HotSwap
+ * %PCI_CAP_ID_PCIX	PCI-X
+ * %PCI_CAP_ID_EXP	PCI Express
+ */
+static int pci_find_own_capability(struct spear_pcie_gadget_config *config,
+		int cap)
+{
+	u32 pos;
+	u32 hdr_type;
+
+	spear_dbi_read_reg(config, PCI_HEADER_TYPE, 1, &hdr_type);
+
+	pos = pci_find_own_cap_start(config, hdr_type);
+	if (pos)
+		pos = pci_find_own_next_cap(config, pos, cap);
+
+	return pos;
+}
+
+static irqreturn_t spear_pcie_gadget_irq(int irq, void *dev_id)
+{
+	return 0;
+}
+
+/*
+ * configfs interfaces show/store functions
+ */
+
+static struct pcie_gadget_target *to_target(struct config_item *item)
+{
+	return item ?
+		container_of(to_configfs_subsystem(to_config_group(item)),
+				struct pcie_gadget_target, subsys) : NULL;
+}
+
+static ssize_t pcie_gadget_link_show(struct config_item *item, char *buf)
+{
+	struct pcie_app_reg __iomem *app_reg = to_target(item)->va_app_base;
+
+	if (readl(&app_reg->app_status_1) & ((u32)1 << XMLH_LINK_UP_ID))
+		return sprintf(buf, "UP");
+	else
+		return sprintf(buf, "DOWN");
+}
+
+static ssize_t pcie_gadget_link_store(struct config_item *item,
+		const char *buf, size_t count)
+{
+	struct pcie_app_reg __iomem *app_reg = to_target(item)->va_app_base;
+
+	if (sysfs_streq(buf, "UP"))
+		writel(readl(&app_reg->app_ctrl_0) | (1 << APP_LTSSM_ENABLE_ID),
+			&app_reg->app_ctrl_0);
+	else if (sysfs_streq(buf, "DOWN"))
+		writel(readl(&app_reg->app_ctrl_0)
+				& ~(1 << APP_LTSSM_ENABLE_ID),
+				&app_reg->app_ctrl_0);
+	else
+		return -EINVAL;
+	return count;
+}
+
+static ssize_t pcie_gadget_int_type_show(struct config_item *item, char *buf)
+{
+	return sprintf(buf, "%s", to_target(item)->int_type);
+}
+
+static ssize_t pcie_gadget_int_type_store(struct config_item *item,
+		const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = to_target(item)
+	u32 cap, vec, flags;
+	ulong vector;
+
+	if (sysfs_streq(buf, "INTA"))
+		spear_dbi_write_reg(config, PCI_INTERRUPT_LINE, 1, 1);
+
+	else if (sysfs_streq(buf, "MSI")) {
+		vector = config->requested_msi;
+		vec = 0;
+		while (vector > 1) {
+			vector /= 2;
+			vec++;
+		}
+		spear_dbi_write_reg(config, PCI_INTERRUPT_LINE, 1, 0);
+		cap = pci_find_own_capability(config, PCI_CAP_ID_MSI);
+		spear_dbi_read_reg(config, cap + PCI_MSI_FLAGS, 1, &flags);
+		flags &= ~PCI_MSI_FLAGS_QMASK;
+		flags |= vec << 1;
+		spear_dbi_write_reg(config, cap + PCI_MSI_FLAGS, 1, flags);
+	} else
+		return -EINVAL;
+
+	strcpy(config->int_type, buf);
+
+	return count;
+}
+
+static ssize_t pcie_gadget_no_of_msi_show(struct config_item *item, char *buf)
+{
+	struct spear_pcie_gadget_config *config = to_target(item)
+	struct pcie_app_reg __iomem *app_reg = to_target(item)->va_app_base;
+	u32 cap, vec, flags;
+	ulong vector;
+
+	if ((readl(&app_reg->msg_status) & (1 << CFG_MSI_EN_ID))
+			!= (1 << CFG_MSI_EN_ID))
+		vector = 0;
+	else {
+		cap = pci_find_own_capability(config, PCI_CAP_ID_MSI);
+		spear_dbi_read_reg(config, cap + PCI_MSI_FLAGS, 1, &flags);
+		flags &= ~PCI_MSI_FLAGS_QSIZE;
+		vec = flags >> 4;
+		vector = 1;
+		while (vec--)
+			vector *= 2;
+	}
+	config->configured_msi = vector;
+
+	return sprintf(buf, "%lu", vector);
+}
+
+static ssize_t pcie_gadget_no_of_msi_store(struct config_item *item,
+		const char *buf, size_t count)
+{
+	int ret;
+
+	ret = kstrtoul(buf, 0, &to_target(item)->requested_msi);
+	if (ret)
+		return ret;
+
+	if (config->requested_msi > 32)
+		config->requested_msi = 32;
+
+	return count;
+}
+
+static ssize_t pcie_gadget_inta_store(struct config_item *item,
+		const char *buf, size_t count)
+{
+	struct pcie_app_reg __iomem *app_reg = to_target(item)->va_app_base;
+	ulong en;
+	int ret;
+
+	ret = kstrtoul(buf, 0, &en);
+	if (ret)
+		return ret;
+
+	if (en)
+		writel(readl(&app_reg->app_ctrl_0) | (1 << SYS_INT_ID),
+				&app_reg->app_ctrl_0);
+	else
+		writel(readl(&app_reg->app_ctrl_0) & ~(1 << SYS_INT_ID),
+				&app_reg->app_ctrl_0);
+
+	return count;
+}
+
+static ssize_t pcie_gadget_send_msi_store(struct config_item *item,
+		const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = to_target(item)
+	struct pcie_app_reg __iomem *app_reg = config->va_app_base;
+	ulong vector;
+	u32 ven_msi;
+	int ret;
+
+	ret = kstrtoul(buf, 0, &vector);
+	if (ret)
+		return ret;
+
+	if (!config->configured_msi)
+		return -EINVAL;
+
+	if (vector >= config->configured_msi)
+		return -EINVAL;
+
+	ven_msi = readl(&app_reg->ven_msi_1);
+	ven_msi &= ~VEN_MSI_FUN_NUM_MASK;
+	ven_msi |= 0 << VEN_MSI_FUN_NUM_ID;
+	ven_msi &= ~VEN_MSI_TC_MASK;
+	ven_msi |= 0 << VEN_MSI_TC_ID;
+	ven_msi &= ~VEN_MSI_VECTOR_MASK;
+	ven_msi |= vector << VEN_MSI_VECTOR_ID;
+
+	/* generating interrupt for msi vector */
+	ven_msi |= VEN_MSI_REQ_EN;
+	writel(ven_msi, &app_reg->ven_msi_1);
+	udelay(1);
+	ven_msi &= ~VEN_MSI_REQ_EN;
+	writel(ven_msi, &app_reg->ven_msi_1);
+
+	return count;
+}
+
+static ssize_t pcie_gadget_vendor_id_show(struct config_item *item, char *buf)
+{
+	u32 id;
+
+	spear_dbi_read_reg(to_target(item), PCI_VENDOR_ID, 2, &id);
+
+	return sprintf(buf, "%x", id);
+}
+
+static ssize_t pcie_gadget_vendor_id_store(struct config_item *item,
+		const char *buf, size_t count)
+{
+	ulong id;
+	int ret;
+
+	ret = kstrtoul(buf, 0, &id);
+	if (ret)
+		return ret;
+
+	spear_dbi_write_reg(to_target(item), PCI_VENDOR_ID, 2, id);
+
+	return count;
+}
+
+static ssize_t pcie_gadget_device_id_show(struct config_item *item, char *buf)
+{
+	u32 id;
+
+	spear_dbi_read_reg(to_target(item), PCI_DEVICE_ID, 2, &id);
+
+	return sprintf(buf, "%x", id);
+}
+
+static ssize_t pcie_gadget_device_id_store(struct config_item *item,
+		const char *buf, size_t count)
+{
+	ulong id;
+	int ret;
+
+	ret = kstrtoul(buf, 0, &id);
+	if (ret)
+		return ret;
+
+	spear_dbi_write_reg(to_target(item), PCI_DEVICE_ID, 2, id);
+
+	return count;
+}
+
+static ssize_t pcie_gadget_bar0_size_show(struct config_item *item, char *buf)
+{
+	return sprintf(buf, "%lx", to_target(item)->bar0_size);
+}
+
+static ssize_t pcie_gadget_bar0_size_store(struct config_item *item,
+		const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = to_target(item)
+	ulong size;
+	u32 pos, pos1;
+	u32 no_of_bit = 0;
+	int ret;
+
+	ret = kstrtoul(buf, 0, &size);
+	if (ret)
+		return ret;
+
+	/* min bar size is 256 */
+	if (size <= 0x100)
+		size = 0x100;
+	/* max bar size is 1MB*/
+	else if (size >= 0x100000)
+		size = 0x100000;
+	else {
+		pos = 0;
+		pos1 = 0;
+		while (pos < 21) {
+			pos = find_next_bit((ulong *)&size, 21, pos);
+			if (pos != 21)
+				pos1 = pos + 1;
+			pos++;
+			no_of_bit++;
+		}
+		if (no_of_bit == 2)
+			pos1--;
+
+		size = 1 << pos1;
+	}
+	config->bar0_size = size;
+	spear_dbi_write_reg(config, PCIE_BAR0_MASK_REG, 4, size - 1);
+
+	return count;
+}
+
+static ssize_t pcie_gadget_bar0_address_show(struct config_item *item,
+		char *buf)
+{
+	struct pcie_app_reg __iomem *app_reg = to_target(item)->va_app_base;
+
+	u32 address = readl(&app_reg->pim0_mem_addr_start);
+
+	return sprintf(buf, "%x", address);
+}
+
+static ssize_t pcie_gadget_bar0_address_store(struct config_item *item,
+		const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = to_target(item)
+	struct pcie_app_reg __iomem *app_reg = config->va_app_base;
+	ulong address;
+	int ret;
+
+	ret = kstrtoul(buf, 0, &address);
+	if (ret)
+		return ret;
+
+	address &= ~(config->bar0_size - 1);
+	if (config->va_bar0_address)
+		iounmap(config->va_bar0_address);
+	config->va_bar0_address = ioremap(address, config->bar0_size);
+	if (!config->va_bar0_address)
+		return -ENOMEM;
+
+	writel(address, &app_reg->pim0_mem_addr_start);
+
+	return count;
+}
+
+static ssize_t pcie_gadget_bar0_rw_offset_show(struct config_item *item,
+		char *buf)
+{
+	return sprintf(buf, "%lx", to_target(item)->bar0_rw_offset);
+}
+
+static ssize_t pcie_gadget_bar0_rw_offset_store(struct config_item *item,
+		const char *buf, size_t count)
+{
+	ulong offset;
+	int ret;
+
+	ret = kstrtoul(buf, 0, &offset);
+	if (ret)
+		return ret;
+
+	if (offset % 4)
+		return -EINVAL;
+
+	to_target(item)->bar0_rw_offset = offset;
+
+	return count;
+}
+
+static ssize_t pcie_gadget_bar0_data_show(struct config_item *item, char *buf)
+{
+	struct spear_pcie_gadget_config *config = to_target(item)
+	ulong data;
+
+	if (!config->va_bar0_address)
+		return -ENOMEM;
+
+	data = readl((ulong)config->va_bar0_address + config->bar0_rw_offset);
+
+	return sprintf(buf, "%lx", data);
+}
+
+static ssize_t pcie_gadget_bar0_data_store(struct config_item *item,
+		const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = to_target(item)
+	ulong data;
+	int ret;
+
+	ret = kstrtoul(buf, 0, &data);
+	if (ret)
+		return ret;
+
+	if (!config->va_bar0_address)
+		return -ENOMEM;
+
+	writel(data, (ulong)config->va_bar0_address + config->bar0_rw_offset);
+
+	return count;
+}
+
+CONFIGFS_ATTR(pcie_gadget_, link);
+CONFIGFS_ATTR(pcie_gadget_, int_type);
+CONFIGFS_ATTR(pcie_gadget_, no_of_msi);
+CONFIGFS_ATTR_WO(pcie_gadget_, inta);
+CONFIGFS_ATTR_WO(pcie_gadget_, send_msi);
+CONFIGFS_ATTR(pcie_gadget_, vendor_id);
+CONFIGFS_ATTR(pcie_gadget_, device_id);
+CONFIGFS_ATTR(pcie_gadget_, bar0_size);
+CONFIGFS_ATTR(pcie_gadget_, bar0_address);
+CONFIGFS_ATTR(pcie_gadget_, bar0_rw_offset);
+CONFIGFS_ATTR(pcie_gadget_, bar0_data);
+
+static struct configfs_attribute *pcie_gadget_target_attrs[] = {
+	&pcie_gadget_attr_link,
+	&pcie_gadget_attr_int_type,
+	&pcie_gadget_attr_no_of_msi,
+	&pcie_gadget_attr_inta,
+	&pcie_gadget_attr_send_msi,
+	&pcie_gadget_attr_vendor_id,
+	&pcie_gadget_attr_device_id,
+	&pcie_gadget_attr_bar0_size,
+	&pcie_gadget_attr_bar0_address,
+	&pcie_gadget_attr_bar0_rw_offset,
+	&pcie_gadget_attr_bar0_data,
+	NULL,
+};
+
+static struct config_item_type pcie_gadget_target_type = {
+	.ct_attrs		= pcie_gadget_target_attrs,
+	.ct_owner		= THIS_MODULE,
+};
+
+static void spear13xx_pcie_device_init(struct spear_pcie_gadget_config *config)
+{
+	struct pcie_app_reg __iomem *app_reg = config->va_app_base;
+
+	/*setup registers for outbound translation */
+
+	writel(config->base, &app_reg->in0_mem_addr_start);
+	writel(app_reg->in0_mem_addr_start + IN0_MEM_SIZE,
+			&app_reg->in0_mem_addr_limit);
+	writel(app_reg->in0_mem_addr_limit + 1, &app_reg->in1_mem_addr_start);
+	writel(app_reg->in1_mem_addr_start + IN1_MEM_SIZE,
+			&app_reg->in1_mem_addr_limit);
+	writel(app_reg->in1_mem_addr_limit + 1, &app_reg->in_io_addr_start);
+	writel(app_reg->in_io_addr_start + IN_IO_SIZE,
+			&app_reg->in_io_addr_limit);
+	writel(app_reg->in_io_addr_limit + 1, &app_reg->in_cfg0_addr_start);
+	writel(app_reg->in_cfg0_addr_start + IN_CFG0_SIZE,
+			&app_reg->in_cfg0_addr_limit);
+	writel(app_reg->in_cfg0_addr_limit + 1, &app_reg->in_cfg1_addr_start);
+	writel(app_reg->in_cfg1_addr_start + IN_CFG1_SIZE,
+			&app_reg->in_cfg1_addr_limit);
+	writel(app_reg->in_cfg1_addr_limit + 1, &app_reg->in_msg_addr_start);
+	writel(app_reg->in_msg_addr_start + IN_MSG_SIZE,
+			&app_reg->in_msg_addr_limit);
+
+	writel(app_reg->in0_mem_addr_start, &app_reg->pom0_mem_addr_start);
+	writel(app_reg->in1_mem_addr_start, &app_reg->pom1_mem_addr_start);
+	writel(app_reg->in_io_addr_start, &app_reg->pom_io_addr_start);
+
+	/*setup registers for inbound translation */
+
+	/* Keep AORAM mapped at BAR0 as default */
+	config->bar0_size = INBOUND_ADDR_MASK + 1;
+	spear_dbi_write_reg(config, PCIE_BAR0_MASK_REG, 4, INBOUND_ADDR_MASK);
+	spear_dbi_write_reg(config, PCI_BASE_ADDRESS_0, 4, 0xC);
+	config->va_bar0_address = ioremap(SPEAR13XX_SYSRAM1_BASE,
+			config->bar0_size);
+
+	writel(SPEAR13XX_SYSRAM1_BASE, &app_reg->pim0_mem_addr_start);
+	writel(0, &app_reg->pim1_mem_addr_start);
+	writel(INBOUND_ADDR_MASK + 1, &app_reg->mem0_addr_offset_limit);
+
+	writel(0x0, &app_reg->pim_io_addr_start);
+	writel(0x0, &app_reg->pim_io_addr_start);
+	writel(0x0, &app_reg->pim_rom_addr_start);
+
+	writel(DEVICE_TYPE_EP | (1 << MISCTRL_EN_ID)
+			| ((u32)1 << REG_TRANSLATION_ENABLE),
+			&app_reg->app_ctrl_0);
+	/* disable all rx interrupts */
+	writel(0, &app_reg->int_mask);
+
+	/* Select INTA as default*/
+	spear_dbi_write_reg(config, PCI_INTERRUPT_LINE, 1, 1);
+}
+
+static int spear_pcie_gadget_probe(struct platform_device *pdev)
+{
+	struct resource *res0, *res1;
+	unsigned int status = 0;
+	int irq;
+	struct clk *clk;
+	static struct pcie_gadget_target *target;
+	struct spear_pcie_gadget_config *config;
+	struct config_item		*cg_item;
+	struct configfs_subsystem *subsys;
+
+	target = devm_kzalloc(&pdev->dev, sizeof(*target), GFP_KERNEL);
+	if (!target) {
+		dev_err(&pdev->dev, "out of memory\n");
+		return -ENOMEM;
+	}
+
+	cg_item = &target->subsys.su_group.cg_item;
+	sprintf(cg_item->ci_namebuf, "pcie_gadget.%d", pdev->id);
+	cg_item->ci_type	= &pcie_gadget_target_type;
+	config = &target->config;
+
+	/* get resource for application registers*/
+	res0 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	config->va_app_base = devm_ioremap_resource(&pdev->dev, res0);
+	if (IS_ERR(config->va_app_base)) {
+		dev_err(&pdev->dev, "ioremap fail\n");
+		return PTR_ERR(config->va_app_base);
+	}
+
+	/* get resource for dbi registers*/
+	res1 = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	config->base = (void __iomem *)res1->start;
+
+	config->va_dbi_base = devm_ioremap_resource(&pdev->dev, res1);
+	if (IS_ERR(config->va_dbi_base)) {
+		dev_err(&pdev->dev, "ioremap fail\n");
+		return PTR_ERR(config->va_dbi_base);
+	}
+
+	platform_set_drvdata(pdev, target);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "no update irq?\n");
+		return irq;
+	}
+
+	status = devm_request_irq(&pdev->dev, irq, spear_pcie_gadget_irq,
+				  0, pdev->name, NULL);
+	if (status) {
+		dev_err(&pdev->dev,
+			"pcie gadget interrupt IRQ%d already claimed\n", irq);
+		return status;
+	}
+
+	/* Register configfs hooks */
+	subsys = &target->subsys;
+	config_group_init(&subsys->su_group);
+	mutex_init(&subsys->su_mutex);
+	status = configfs_register_subsystem(subsys);
+	if (status)
+		return status;
+
+	/*
+	 * init basic pcie application registers
+	 * do not enable clock if it is PCIE0.Ideally , all controller should
+	 * have been independent from others with respect to clock. But PCIE1
+	 * and 2 depends on PCIE0.So PCIE0 clk is provided during board init.
+	 */
+	if (pdev->id == 1) {
+		/*
+		 * Ideally CFG Clock should have been also enabled here. But
+		 * it is done currently during board init routne
+		 */
+		clk = clk_get_sys("pcie1", NULL);
+		if (IS_ERR(clk)) {
+			pr_err("%s:couldn't get clk for pcie1\n", __func__);
+			return PTR_ERR(clk);
+		}
+		status = clk_enable(clk);
+		if (status) {
+			pr_err("%s:couldn't enable clk for pcie1\n", __func__);
+			return status;
+		}
+	} else if (pdev->id == 2) {
+		/*
+		 * Ideally CFG Clock should have been also enabled here. But
+		 * it is done currently during board init routne
+		 */
+		clk = clk_get_sys("pcie2", NULL);
+		if (IS_ERR(clk)) {
+			pr_err("%s:couldn't get clk for pcie2\n", __func__);
+			return PTR_ERR(clk);
+		}
+		status = clk_enable(clk);
+		if (status) {
+			pr_err("%s:couldn't enable clk for pcie2\n", __func__);
+			return status;
+		}
+	}
+	spear13xx_pcie_device_init(config);
+
+	return 0;
+}
+
+static int spear_pcie_gadget_remove(struct platform_device *pdev)
+{
+	static struct pcie_gadget_target *target;
+
+	target = platform_get_drvdata(pdev);
+
+	configfs_unregister_subsystem(&target->subsys);
+
+	return 0;
+}
+
+static void spear_pcie_gadget_shutdown(struct platform_device *pdev)
+{
+}
+
+static struct platform_driver spear_pcie_gadget_driver = {
+	.probe = spear_pcie_gadget_probe,
+	.remove = spear_pcie_gadget_remove,
+	.shutdown = spear_pcie_gadget_shutdown,
+	.driver = {
+		.name = "pcie-gadget-spear",
+		.bus = &platform_bus_type
+	},
+};
+
+module_platform_driver(spear_pcie_gadget_driver);
+
+MODULE_ALIAS("platform:pcie-gadget-spear");
+MODULE_AUTHOR("Pratyush Anand");
+MODULE_LICENSE("GPL");