diff mbox

[V2,45/69] ST SPEAr: PCIE gadget suppport

Message ID c91308e26397dbe49f384c7d3cf168593e1fe8b0.1285933332.git.viresh.kumar@st.com (mailing list archive)
State Not Applicable
Headers show

Commit Message

Viresh KUMAR Oct. 1, 2010, 11:56 a.m. UTC
None
diff mbox

Patch

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index b743312..e19deda 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -344,6 +344,16 @@  config DS1682
 	  This driver can also be built as a module.  If so, the module
 	  will be called ds1682.
 
+config SPEAR13XX_PCIE_GADGET
+	bool "PCIE gadget support for SPEAr13XX platform"
+	depends on ARCH_SPEAR13XX
+	default n
+	help
+	 This option enables gadget support for PCIE controller. If
+	 board file defines any controller as PCIE endpoint then a sysfs
+	 entry will be created for that controller. User can use these
+	 sysfs node to configure PCIE EP as per his requirements.
+
 config TI_DAC7512
 	tristate "Texas Instruments DAC7512"
 	depends on SPI && SYSFS
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 42eab95..9408f23 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -33,5 +33,6 @@  obj-$(CONFIG_IWMC3200TOP)      += iwmc3200top/
 obj-$(CONFIG_HMC6352)		+= hmc6352.o
 obj-y				+= eeprom/
 obj-y				+= cb710/
+obj-$(CONFIG_SPEAR13XX_PCIE_GADGET)	+= spear13xx_pcie_gadget.o
 obj-$(CONFIG_VMWARE_BALLOON)	+= vmw_balloon.o
 obj-$(CONFIG_ARM_CHARLCD)	+= arm-charlcd.o
diff --git a/drivers/misc/spear13xx_pcie_gadget.c b/drivers/misc/spear13xx_pcie_gadget.c
new file mode 100644
index 0000000..dc63a28
--- /dev/null
+++ b/drivers/misc/spear13xx_pcie_gadget.c
@@ -0,0 +1,888 @@ 
+/*
+ * drivers/misc/spear13xx_pcie_gadget.c
+ *
+ * Copyright (C) 2010 ST Microelectronics
+ * Pratyush Anand<pratyush.anand@st.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/delay.h>
+#include <linux/irq.h>
+#include <linux/clk.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/pci_regs.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];
+	u32 requested_msi;
+	u32 configured_msi;
+	u32 bar0_size;
+	u32 bar0_rw_offset;
+	u32 va_bar0_address;
+};
+
+static void enable_dbi_access(struct pcie_app_reg *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 *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 *app_reg
+		= (struct pcie_app_reg *) config->va_app_base;
+	u32 va_address;
+
+	/* Enable DBI access */
+	enable_dbi_access(app_reg);
+
+	va_address = (u32)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 *app_reg
+		= (struct pcie_app_reg *) config->va_app_base;
+	u32 va_address;
+
+	/* Enable DBI access */
+	enable_dbi_access(app_reg);
+
+	va_address = (u32)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;
+}
+
+static ssize_t pcie_gadget_show_link(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	struct pcie_app_reg *app_reg =
+		(struct pcie_app_reg *)config->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_store_link(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	struct pcie_app_reg *app_reg =
+		(struct pcie_app_reg *)config->va_app_base;
+	char link[10];
+
+	if (sscanf(buf, "%s", link) != 1)
+		return -EINVAL;
+
+	if (!strcmp(link, "UP"))
+		writel(readl(&app_reg->app_ctrl_0) | (1 << APP_LTSSM_ENABLE_ID),
+			&app_reg->app_ctrl_0);
+	else
+		writel(readl(&app_reg->app_ctrl_0)
+				& ~(1 << APP_LTSSM_ENABLE_ID),
+				&app_reg->app_ctrl_0);
+	return count;
+}
+
+static DEVICE_ATTR(link, S_IWUSR | S_IRUGO, pcie_gadget_show_link,
+		pcie_gadget_store_link);
+
+static ssize_t pcie_gadget_show_int_type(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s", config->int_type);
+}
+
+static ssize_t pcie_gadget_store_int_type(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	char int_type[10];
+	u32 cap, vector, vec, flags;
+
+	if (sscanf(buf, "%s", int_type) != 1)
+		return -EINVAL;
+
+	if (!strcmp(int_type, "INTA"))
+		spear_dbi_write_reg(config, PCI_INTERRUPT_LINE, 1, 1);
+
+	else if (!strcmp(int_type, "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);
+	}
+
+	strcpy(config->int_type, int_type);
+
+	return count;
+}
+
+static DEVICE_ATTR(int_type, S_IWUSR | S_IRUGO, pcie_gadget_show_int_type,
+		pcie_gadget_store_int_type);
+
+static ssize_t pcie_gadget_show_no_of_msi(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	struct pcie_app_reg *app_reg =
+		(struct pcie_app_reg *)config->va_app_base;
+	u32 cap, vector, vec, flags;
+
+	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, "%u", vector);
+}
+
+static ssize_t pcie_gadget_store_no_of_msi(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+
+	if (sscanf(buf, "%u", &config->requested_msi) != 1)
+		return -EINVAL;
+	if (config->requested_msi > 32)
+		config->requested_msi = 32;
+
+	return count;
+}
+
+static DEVICE_ATTR(no_of_msi, S_IWUSR | S_IRUGO, pcie_gadget_show_no_of_msi,
+		pcie_gadget_store_no_of_msi);
+
+static ssize_t pcie_gadget_store_inta(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	struct pcie_app_reg *app_reg =
+		(struct pcie_app_reg *)config->va_app_base;
+	int en;
+
+	if (sscanf(buf, "%d", &en) != 1)
+		return -EINVAL;
+
+	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 DEVICE_ATTR(inta, S_IWUSR, NULL, pcie_gadget_store_inta);
+
+static ssize_t pcie_gadget_store_send_msi(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	struct pcie_app_reg *app_reg =
+		(struct pcie_app_reg *)config->va_app_base;
+	int vector;
+	u32 ven_msi;
+
+	if (sscanf(buf, "%d", &vector) != 1)
+		return -EINVAL;
+
+	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);
+	/*need to wait till this bit is cleared, it is not cleared
+	 * autometically[Bug RTL] TBD*/
+	udelay(1);
+	ven_msi &= ~VEN_MSI_REQ_EN;
+	writel(ven_msi, &app_reg->ven_msi_1);
+
+	return count;
+}
+
+static DEVICE_ATTR(send_msi, S_IWUSR, NULL, pcie_gadget_store_send_msi);
+
+static ssize_t pcie_gadget_show_vendor_id(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	u32 id;
+
+	spear_dbi_read_reg(config, PCI_VENDOR_ID, 2, &id);
+
+	return sprintf(buf, "%x", id);
+}
+
+static ssize_t pcie_gadget_store_vendor_id(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	u32 id;
+
+	if (sscanf(buf, "%x", &id) != 1)
+		return -EINVAL;
+
+	spear_dbi_write_reg(config, PCI_VENDOR_ID, 2, id);
+
+	return count;
+}
+
+static DEVICE_ATTR(vendor_id, S_IWUSR | S_IRUGO, pcie_gadget_show_vendor_id,
+		pcie_gadget_store_vendor_id);
+
+static ssize_t pcie_gadget_show_device_id(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	u32 id;
+
+	spear_dbi_read_reg(config, PCI_DEVICE_ID, 2, &id);
+
+	return sprintf(buf, "%x", id);
+}
+
+static ssize_t pcie_gadget_store_device_id(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	u32 id;
+
+	if (sscanf(buf, "%x", &id) != 1)
+		return -EINVAL;
+
+	spear_dbi_write_reg(config, PCI_DEVICE_ID, 2, id);
+
+	return count;
+}
+
+static DEVICE_ATTR(device_id, S_IWUSR | S_IRUGO, pcie_gadget_show_device_id,
+		pcie_gadget_store_device_id);
+
+static ssize_t pcie_gadget_show_bar0_size(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%x", config->bar0_size);
+}
+
+static ssize_t pcie_gadget_store_bar0_size(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	u32 size, pos, pos1;
+	u32 no_of_bit = 0;
+
+	if (sscanf(buf, "%x", &size) != 1)
+		return -EINVAL;
+	/* as per PCIE specs, min bar size supported is 128 bytes. But
+	 * our controller supports min as 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((unsigned long *)&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 DEVICE_ATTR(bar0_size, S_IWUSR | S_IRUGO, pcie_gadget_show_bar0_size,
+		pcie_gadget_store_bar0_size);
+
+static ssize_t pcie_gadget_show_bar0_address(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	struct pcie_app_reg *app_reg =
+		(struct pcie_app_reg *)config->va_app_base;
+
+	u32 address = readl(&app_reg->pim0_mem_addr_start);
+
+	return sprintf(buf, "%x", address);
+}
+
+static ssize_t pcie_gadget_store_bar0_address(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	struct pcie_app_reg *app_reg =
+		(struct pcie_app_reg *)config->va_app_base;
+	u32 address;
+
+	if (sscanf(buf, "%x", &address) != 1)
+		return -EINVAL;
+
+	address &= ~(config->bar0_size - 1);
+	if (config->va_bar0_address)
+		iounmap((void *)config->va_bar0_address);
+	config->va_bar0_address = (u32)ioremap(address, config->bar0_size);
+	if (!config->va_bar0_address)
+		return -ENOMEM;
+
+	writel(address, &app_reg->pim0_mem_addr_start);
+
+	return count;
+}
+
+static DEVICE_ATTR(bar0_address, S_IWUSR | S_IRUGO,
+		pcie_gadget_show_bar0_address, pcie_gadget_store_bar0_address);
+
+static ssize_t pcie_gadget_show_bar0_rw_offset(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%x", config->bar0_rw_offset);
+}
+
+static ssize_t pcie_gadget_store_bar0_rw_offset(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	u32 offset;
+
+	if (sscanf(buf, "%x", &offset) != 1)
+		return -EINVAL;
+
+	if (offset % 4)
+		return -EINVAL;
+
+	config->bar0_rw_offset = offset;
+
+	return count;
+}
+
+static DEVICE_ATTR(bar0_rw_offset, S_IWUSR | S_IRUGO,
+	pcie_gadget_show_bar0_rw_offset, pcie_gadget_store_bar0_rw_offset);
+
+static ssize_t pcie_gadget_show_bar0_data(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	u32 data;
+
+	if (!config->va_bar0_address)
+		return -ENOMEM;
+
+	data = readl(config->va_bar0_address + config->bar0_rw_offset);
+
+	return sprintf(buf, "%x", data);
+}
+
+static ssize_t pcie_gadget_store_bar0_data(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct spear_pcie_gadget_config *config = dev_get_drvdata(dev);
+	u32 data;
+
+	if (sscanf(buf, "%x", &data) != 1)
+		return -EINVAL;
+
+	if (!config->va_bar0_address)
+		return -ENOMEM;
+
+	writel(data, config->va_bar0_address + config->bar0_rw_offset);
+
+	return count;
+}
+
+static DEVICE_ATTR(bar0_data, S_IWUSR | S_IRUGO,
+		pcie_gadget_show_bar0_data, pcie_gadget_store_bar0_data);
+
+static ssize_t pcie_gadget_show_help(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	char text[] = "\t\tlink read->ltssm status\n \
+		link write->arg1 = UP to enable ltsmm DOWN to disable\n \
+		int_type read->type of supported interrupt\n \
+		int_type write->arg1 = interrupt type to be configured and\n \
+		can be INTA, MSI or NO_INT\n \
+		(select MSI only when you have programmed no_of_msi)\n \
+		no_of_msi read->zero if MSI is not enabled by host\n \
+		and positive value is the number of MSI vector granted\n \
+		no_of_msi write->arg1 = number of MSI vector needed\n \
+		inta write->arg1 = 1 to assert INTA and 0 to de-assert\n \
+		send_msi write->arg1 = MSI vector to be send\n \
+		vendor_id read->programmed vendor id (hex)\n\
+		vendor_id write->arg1 = vendor id(hex) to be programmed\n \
+		device_id read->programmed device id(hex)\n \
+		device_id write->arg1 = device id(hex) to be programmed\n \
+		bar0_size read->size of bar0 in hex\n \
+		bar0_size write->arg1= size of bar0 in hex\n \
+		(default bar0 size is 1000 (hex) bytes)\n \
+		bar0_address read->address of bar0 mapped area in hex\n \
+		bar0_address write->arg1 = address of bar0 mapped area in hex\n\
+		(default mapping of bar0 is SYSRAM1(E0800000)\n \
+		(always program bar size before bar address)\n \
+		(kernel might modify bar size and address to align)\n \
+		(read back bar size and address after writing to check)\n \
+		bar0_rw_offset read->offset of bar0 for which bar0_data \n \
+		will return value\n \
+		bar0_rw_offset write->arg1 = offset of bar0 for which\n \
+		bar0_data will write value\n \
+		bar0_data read->data at bar0_rw_offset\n \
+		bar0_data write->arg1 = data to be written at\n \
+		bar0_rw_offset\n";
+
+	int size = (sizeof(text) < PAGE_SIZE) ? sizeof(text) : PAGE_SIZE;
+
+	return snprintf(buf, size, "%s", text);
+}
+
+static DEVICE_ATTR(help, S_IRUGO, pcie_gadget_show_help, NULL);
+
+static struct attribute *pcie_gadget_attributes[] = {
+	&dev_attr_link.attr,
+	&dev_attr_int_type.attr,
+	&dev_attr_no_of_msi.attr,
+	&dev_attr_inta.attr,
+	&dev_attr_send_msi.attr,
+	&dev_attr_vendor_id.attr,
+	&dev_attr_device_id.attr,
+	&dev_attr_bar0_size.attr,
+	&dev_attr_bar0_address.attr,
+	&dev_attr_bar0_rw_offset.attr,
+	&dev_attr_bar0_data.attr,
+	&dev_attr_help.attr,
+	NULL
+};
+
+static const struct attribute_group pcie_gadget_attr_group = {
+	.attrs = pcie_gadget_attributes,
+};
+
+static void spear13xx_pcie_device_init(struct spear_pcie_gadget_config *config)
+{
+	struct pcie_app_reg *app_reg =
+		(struct pcie_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 = (u32)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 __devinit spear_pcie_gadget_probe(struct platform_device *pdev)
+{
+	struct resource *res0, *res1;
+	struct spear_pcie_gadget_config *config;
+	unsigned int status = 0;
+	int irq;
+	struct clk *clk;
+
+	/* get resource for application registers*/
+
+	res0 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res0) {
+		dev_err(&pdev->dev, "no resource defined\n");
+		return -EBUSY;
+	}
+	if (!request_mem_region(res0->start, resource_size(res0),
+				pdev->name)) {
+		dev_err(&pdev->dev, "pcie gadget region already	claimed\n");
+		return -EBUSY;
+	}
+	/* get resource for dbi registers*/
+
+	res1 = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (!res1) {
+		dev_err(&pdev->dev, "no resource defined\n");
+		goto err_rel_res0;
+	}
+	if (!request_mem_region(res1->start, resource_size(res1),
+				pdev->name)) {
+		dev_err(&pdev->dev, "pcie gadget region already	claimed\n");
+		goto err_rel_res0;
+	}
+
+	config = kzalloc(sizeof(*config), GFP_KERNEL);
+	if (!config) {
+		dev_err(&pdev->dev, "out of memory\n");
+		status = -ENOMEM;
+		goto err_rel_res;
+	}
+
+	config->va_app_base = ioremap(res0->start, resource_size(res0));
+	if (!config->va_app_base) {
+		dev_err(&pdev->dev, "ioremap fail\n");
+		status = -ENOMEM;
+		goto err_kzalloc;
+	}
+
+	config->base = (void *)res1->start;
+
+	config->va_dbi_base = ioremap(res1->start, resource_size(res1));
+	if (!config->va_dbi_base) {
+		dev_err(&pdev->dev, "ioremap fail\n");
+		status = -ENOMEM;
+		goto err_iounmap_app;
+	}
+
+	dev_set_drvdata(&pdev->dev, config);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "no update irq?\n");
+		status = irq;
+		goto err_iounmap;
+	}
+
+	status = request_irq(irq, spear_pcie_gadget_irq, 0, pdev->name, NULL);
+	if (status) {
+		dev_err(&pdev->dev, "pcie gadget interrupt IRQ%d already \
+				claimed\n", irq);
+		goto err_get_irq;
+	}
+	/* Register sysfs hooks */
+	status = sysfs_create_group(&pdev->dev.kobj, &pcie_gadget_attr_group);
+	if (status)
+		goto err_irq;
+
+	/* 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 (!clk) {
+			pr_err("%s:couldn't get clk for pcie1\n", __func__);
+			goto err_irq;
+		}
+		if (clk_enable(clk)) {
+			pr_err("%s:couldn't enable clk for pcie1\n", __func__);
+			goto err_irq;
+		}
+	} 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 (!clk) {
+			pr_err("%s:couldn't get clk for pcie2\n", __func__);
+			goto err_irq;
+		}
+		if (clk_enable(clk)) {
+			pr_err("%s:couldn't enable clk for pcie2\n", __func__);
+			goto err_irq;
+		}
+	}
+	spear13xx_pcie_device_init(config);
+
+	return 0;
+err_irq:
+	free_irq(irq, NULL);
+err_get_irq:
+	dev_set_drvdata(&pdev->dev, NULL);
+err_iounmap:
+	iounmap(config->va_dbi_base);
+err_iounmap_app:
+	iounmap(config->va_app_base);
+err_kzalloc:
+	kfree(config);
+err_rel_res:
+	release_mem_region(res1->start, resource_size(res1));
+err_rel_res0:
+	release_mem_region(res0->start, resource_size(res0));
+	return status;
+}
+
+static int __devexit spear_pcie_gadget_remove(struct platform_device *pdev)
+{
+	struct resource *res0, *res1;
+	struct spear_pcie_gadget_config *config;
+	int irq;
+
+	res0 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	res1 = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	irq = platform_get_irq(pdev, 0);
+	config = dev_get_drvdata(&pdev->dev);
+
+	free_irq(irq, NULL);
+	dev_set_drvdata(&pdev->dev, NULL);
+	iounmap(config->va_dbi_base);
+	iounmap(config->va_app_base);
+	kfree(config);
+	release_mem_region(res1->start, resource_size(res1));
+	release_mem_region(res0->start, resource_size(res0));
+	sysfs_remove_group(&pdev->dev.kobj, &pcie_gadget_attr_group);
+
+	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
+	},
+};
+
+static int __init spear_pcie_gadget_init(void)
+{
+	return platform_driver_register(&spear_pcie_gadget_driver);
+}
+module_init(spear_pcie_gadget_init);
+
+static void __exit spear_pcie_gadget_exit(void)
+{
+	platform_driver_unregister(&spear_pcie_gadget_driver);
+}
+module_exit(spear_pcie_gadget_exit);
+
+MODULE_ALIAS("pcie-gadget-spear");
+MODULE_AUTHOR("Pratyush Anand");
+MODULE_LICENSE("GPL");