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authorLinus Torvalds2005-04-16 15:20:36 -0700
committerLinus Torvalds2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/ia64/pci
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/ia64/pci')
-rw-r--r--arch/ia64/pci/Makefile4
-rw-r--r--arch/ia64/pci/pci.c735
2 files changed, 739 insertions, 0 deletions
diff --git a/arch/ia64/pci/Makefile b/arch/ia64/pci/Makefile
new file mode 100644
index 000000000000..e66889e6922a
--- /dev/null
+++ b/arch/ia64/pci/Makefile
@@ -0,0 +1,4 @@
+#
+# Makefile for the ia64-specific parts of the pci bus
+#
+obj-y := pci.o
diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c
new file mode 100644
index 000000000000..88641e5095b5
--- /dev/null
+++ b/arch/ia64/pci/pci.c
@@ -0,0 +1,735 @@
+/*
+ * pci.c - Low-Level PCI Access in IA-64
+ *
+ * Derived from bios32.c of i386 tree.
+ *
+ * (c) Copyright 2002, 2005 Hewlett-Packard Development Company, L.P.
+ * David Mosberger-Tang <davidm@hpl.hp.com>
+ * Bjorn Helgaas <bjorn.helgaas@hp.com>
+ * Copyright (C) 2004 Silicon Graphics, Inc.
+ *
+ * Note: Above list of copyright holders is incomplete...
+ */
+#include <linux/config.h>
+
+#include <linux/acpi.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/slab.h>
+#include <linux/smp_lock.h>
+#include <linux/spinlock.h>
+
+#include <asm/machvec.h>
+#include <asm/page.h>
+#include <asm/segment.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/sal.h>
+#include <asm/smp.h>
+#include <asm/irq.h>
+#include <asm/hw_irq.h>
+
+
+static int pci_routeirq;
+
+/*
+ * Low-level SAL-based PCI configuration access functions. Note that SAL
+ * calls are already serialized (via sal_lock), so we don't need another
+ * synchronization mechanism here.
+ */
+
+#define PCI_SAL_ADDRESS(seg, bus, devfn, reg) \
+ (((u64) seg << 24) | (bus << 16) | (devfn << 8) | (reg))
+
+/* SAL 3.2 adds support for extended config space. */
+
+#define PCI_SAL_EXT_ADDRESS(seg, bus, devfn, reg) \
+ (((u64) seg << 28) | (bus << 20) | (devfn << 12) | (reg))
+
+static int
+pci_sal_read (unsigned int seg, unsigned int bus, unsigned int devfn,
+ int reg, int len, u32 *value)
+{
+ u64 addr, data = 0;
+ int mode, result;
+
+ if (!value || (seg > 65535) || (bus > 255) || (devfn > 255) || (reg > 4095))
+ return -EINVAL;
+
+ if ((seg | reg) <= 255) {
+ addr = PCI_SAL_ADDRESS(seg, bus, devfn, reg);
+ mode = 0;
+ } else {
+ addr = PCI_SAL_EXT_ADDRESS(seg, bus, devfn, reg);
+ mode = 1;
+ }
+ result = ia64_sal_pci_config_read(addr, mode, len, &data);
+ if (result != 0)
+ return -EINVAL;
+
+ *value = (u32) data;
+ return 0;
+}
+
+static int
+pci_sal_write (unsigned int seg, unsigned int bus, unsigned int devfn,
+ int reg, int len, u32 value)
+{
+ u64 addr;
+ int mode, result;
+
+ if ((seg > 65535) || (bus > 255) || (devfn > 255) || (reg > 4095))
+ return -EINVAL;
+
+ if ((seg | reg) <= 255) {
+ addr = PCI_SAL_ADDRESS(seg, bus, devfn, reg);
+ mode = 0;
+ } else {
+ addr = PCI_SAL_EXT_ADDRESS(seg, bus, devfn, reg);
+ mode = 1;
+ }
+ result = ia64_sal_pci_config_write(addr, mode, len, value);
+ if (result != 0)
+ return -EINVAL;
+ return 0;
+}
+
+static struct pci_raw_ops pci_sal_ops = {
+ .read = pci_sal_read,
+ .write = pci_sal_write
+};
+
+struct pci_raw_ops *raw_pci_ops = &pci_sal_ops;
+
+static int
+pci_read (struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *value)
+{
+ return raw_pci_ops->read(pci_domain_nr(bus), bus->number,
+ devfn, where, size, value);
+}
+
+static int
+pci_write (struct pci_bus *bus, unsigned int devfn, int where, int size, u32 value)
+{
+ return raw_pci_ops->write(pci_domain_nr(bus), bus->number,
+ devfn, where, size, value);
+}
+
+struct pci_ops pci_root_ops = {
+ .read = pci_read,
+ .write = pci_write,
+};
+
+#ifdef CONFIG_NUMA
+extern acpi_status acpi_map_iosapic(acpi_handle, u32, void *, void **);
+static void acpi_map_iosapics(void)
+{
+ acpi_get_devices(NULL, acpi_map_iosapic, NULL, NULL);
+}
+#else
+static void acpi_map_iosapics(void)
+{
+ return;
+}
+#endif /* CONFIG_NUMA */
+
+static int __init
+pci_acpi_init (void)
+{
+ struct pci_dev *dev = NULL;
+
+ printk(KERN_INFO "PCI: Using ACPI for IRQ routing\n");
+
+ acpi_map_iosapics();
+
+ if (pci_routeirq) {
+ /*
+ * PCI IRQ routing is set up by pci_enable_device(), but we
+ * also do it here in case there are still broken drivers that
+ * don't use pci_enable_device().
+ */
+ printk(KERN_INFO "PCI: Routing interrupts for all devices because \"pci=routeirq\" specified\n");
+ for_each_pci_dev(dev)
+ acpi_pci_irq_enable(dev);
+ } else
+ printk(KERN_INFO "PCI: If a device doesn't work, try \"pci=routeirq\". If it helps, post a report\n");
+
+ return 0;
+}
+
+subsys_initcall(pci_acpi_init);
+
+/* Called by ACPI when it finds a new root bus. */
+
+static struct pci_controller * __devinit
+alloc_pci_controller (int seg)
+{
+ struct pci_controller *controller;
+
+ controller = kmalloc(sizeof(*controller), GFP_KERNEL);
+ if (!controller)
+ return NULL;
+
+ memset(controller, 0, sizeof(*controller));
+ controller->segment = seg;
+ return controller;
+}
+
+static u64 __devinit
+add_io_space (struct acpi_resource_address64 *addr)
+{
+ u64 offset;
+ int sparse = 0;
+ int i;
+
+ if (addr->address_translation_offset == 0)
+ return IO_SPACE_BASE(0); /* part of legacy IO space */
+
+ if (addr->attribute.io.translation_attribute == ACPI_SPARSE_TRANSLATION)
+ sparse = 1;
+
+ offset = (u64) ioremap(addr->address_translation_offset, 0);
+ for (i = 0; i < num_io_spaces; i++)
+ if (io_space[i].mmio_base == offset &&
+ io_space[i].sparse == sparse)
+ return IO_SPACE_BASE(i);
+
+ if (num_io_spaces == MAX_IO_SPACES) {
+ printk("Too many IO port spaces\n");
+ return ~0;
+ }
+
+ i = num_io_spaces++;
+ io_space[i].mmio_base = offset;
+ io_space[i].sparse = sparse;
+
+ return IO_SPACE_BASE(i);
+}
+
+static acpi_status __devinit
+count_window (struct acpi_resource *resource, void *data)
+{
+ unsigned int *windows = (unsigned int *) data;
+ struct acpi_resource_address64 addr;
+ acpi_status status;
+
+ status = acpi_resource_to_address64(resource, &addr);
+ if (ACPI_SUCCESS(status))
+ if (addr.resource_type == ACPI_MEMORY_RANGE ||
+ addr.resource_type == ACPI_IO_RANGE)
+ (*windows)++;
+
+ return AE_OK;
+}
+
+struct pci_root_info {
+ struct pci_controller *controller;
+ char *name;
+};
+
+static __devinit acpi_status add_window(struct acpi_resource *res, void *data)
+{
+ struct pci_root_info *info = data;
+ struct pci_window *window;
+ struct acpi_resource_address64 addr;
+ acpi_status status;
+ unsigned long flags, offset = 0;
+ struct resource *root;
+
+ status = acpi_resource_to_address64(res, &addr);
+ if (!ACPI_SUCCESS(status))
+ return AE_OK;
+
+ if (!addr.address_length)
+ return AE_OK;
+
+ if (addr.resource_type == ACPI_MEMORY_RANGE) {
+ flags = IORESOURCE_MEM;
+ root = &iomem_resource;
+ offset = addr.address_translation_offset;
+ } else if (addr.resource_type == ACPI_IO_RANGE) {
+ flags = IORESOURCE_IO;
+ root = &ioport_resource;
+ offset = add_io_space(&addr);
+ if (offset == ~0)
+ return AE_OK;
+ } else
+ return AE_OK;
+
+ window = &info->controller->window[info->controller->windows++];
+ window->resource.name = info->name;
+ window->resource.flags = flags;
+ window->resource.start = addr.min_address_range + offset;
+ window->resource.end = addr.max_address_range + offset;
+ window->resource.child = NULL;
+ window->offset = offset;
+
+ if (insert_resource(root, &window->resource)) {
+ printk(KERN_ERR "alloc 0x%lx-0x%lx from %s for %s failed\n",
+ window->resource.start, window->resource.end,
+ root->name, info->name);
+ }
+
+ return AE_OK;
+}
+
+static void __devinit
+pcibios_setup_root_windows(struct pci_bus *bus, struct pci_controller *ctrl)
+{
+ int i, j;
+
+ j = 0;
+ for (i = 0; i < ctrl->windows; i++) {
+ struct resource *res = &ctrl->window[i].resource;
+ /* HP's firmware has a hack to work around a Windows bug.
+ * Ignore these tiny memory ranges */
+ if ((res->flags & IORESOURCE_MEM) &&
+ (res->end - res->start < 16))
+ continue;
+ if (j >= PCI_BUS_NUM_RESOURCES) {
+ printk("Ignoring range [%lx-%lx] (%lx)\n", res->start,
+ res->end, res->flags);
+ continue;
+ }
+ bus->resource[j++] = res;
+ }
+}
+
+struct pci_bus * __devinit
+pci_acpi_scan_root(struct acpi_device *device, int domain, int bus)
+{
+ struct pci_root_info info;
+ struct pci_controller *controller;
+ unsigned int windows = 0;
+ struct pci_bus *pbus;
+ char *name;
+
+ controller = alloc_pci_controller(domain);
+ if (!controller)
+ goto out1;
+
+ controller->acpi_handle = device->handle;
+
+ acpi_walk_resources(device->handle, METHOD_NAME__CRS, count_window,
+ &windows);
+ controller->window = kmalloc(sizeof(*controller->window) * windows,
+ GFP_KERNEL);
+ if (!controller->window)
+ goto out2;
+
+ name = kmalloc(16, GFP_KERNEL);
+ if (!name)
+ goto out3;
+
+ sprintf(name, "PCI Bus %04x:%02x", domain, bus);
+ info.controller = controller;
+ info.name = name;
+ acpi_walk_resources(device->handle, METHOD_NAME__CRS, add_window,
+ &info);
+
+ pbus = pci_scan_bus(bus, &pci_root_ops, controller);
+ if (pbus)
+ pcibios_setup_root_windows(pbus, controller);
+
+ return pbus;
+
+out3:
+ kfree(controller->window);
+out2:
+ kfree(controller);
+out1:
+ return NULL;
+}
+
+void pcibios_resource_to_bus(struct pci_dev *dev,
+ struct pci_bus_region *region, struct resource *res)
+{
+ struct pci_controller *controller = PCI_CONTROLLER(dev);
+ unsigned long offset = 0;
+ int i;
+
+ for (i = 0; i < controller->windows; i++) {
+ struct pci_window *window = &controller->window[i];
+ if (!(window->resource.flags & res->flags))
+ continue;
+ if (window->resource.start > res->start)
+ continue;
+ if (window->resource.end < res->end)
+ continue;
+ offset = window->offset;
+ break;
+ }
+
+ region->start = res->start - offset;
+ region->end = res->end - offset;
+}
+EXPORT_SYMBOL(pcibios_resource_to_bus);
+
+void pcibios_bus_to_resource(struct pci_dev *dev,
+ struct resource *res, struct pci_bus_region *region)
+{
+ struct pci_controller *controller = PCI_CONTROLLER(dev);
+ unsigned long offset = 0;
+ int i;
+
+ for (i = 0; i < controller->windows; i++) {
+ struct pci_window *window = &controller->window[i];
+ if (!(window->resource.flags & res->flags))
+ continue;
+ if (window->resource.start - window->offset > region->start)
+ continue;
+ if (window->resource.end - window->offset < region->end)
+ continue;
+ offset = window->offset;
+ break;
+ }
+
+ res->start = region->start + offset;
+ res->end = region->end + offset;
+}
+
+static void __devinit pcibios_fixup_device_resources(struct pci_dev *dev)
+{
+ struct pci_bus_region region;
+ int i;
+ int limit = (dev->hdr_type == PCI_HEADER_TYPE_NORMAL) ? \
+ PCI_BRIDGE_RESOURCES : PCI_NUM_RESOURCES;
+
+ for (i = 0; i < limit; i++) {
+ if (!dev->resource[i].flags)
+ continue;
+ region.start = dev->resource[i].start;
+ region.end = dev->resource[i].end;
+ pcibios_bus_to_resource(dev, &dev->resource[i], &region);
+ pci_claim_resource(dev, i);
+ }
+}
+
+/*
+ * Called after each bus is probed, but before its children are examined.
+ */
+void __devinit
+pcibios_fixup_bus (struct pci_bus *b)
+{
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &b->devices, bus_list)
+ pcibios_fixup_device_resources(dev);
+
+ return;
+}
+
+void __devinit
+pcibios_update_irq (struct pci_dev *dev, int irq)
+{
+ pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
+
+ /* ??? FIXME -- record old value for shutdown. */
+}
+
+static inline int
+pcibios_enable_resources (struct pci_dev *dev, int mask)
+{
+ u16 cmd, old_cmd;
+ int idx;
+ struct resource *r;
+
+ if (!dev)
+ return -EINVAL;
+
+ pci_read_config_word(dev, PCI_COMMAND, &cmd);
+ old_cmd = cmd;
+ for (idx=0; idx<6; idx++) {
+ /* Only set up the desired resources. */
+ if (!(mask & (1 << idx)))
+ continue;
+
+ r = &dev->resource[idx];
+ if (!r->start && r->end) {
+ printk(KERN_ERR
+ "PCI: Device %s not available because of resource collisions\n",
+ pci_name(dev));
+ return -EINVAL;
+ }
+ if (r->flags & IORESOURCE_IO)
+ cmd |= PCI_COMMAND_IO;
+ if (r->flags & IORESOURCE_MEM)
+ cmd |= PCI_COMMAND_MEMORY;
+ }
+ if (dev->resource[PCI_ROM_RESOURCE].start)
+ cmd |= PCI_COMMAND_MEMORY;
+ if (cmd != old_cmd) {
+ printk("PCI: Enabling device %s (%04x -> %04x)\n", pci_name(dev), old_cmd, cmd);
+ pci_write_config_word(dev, PCI_COMMAND, cmd);
+ }
+ return 0;
+}
+
+int
+pcibios_enable_device (struct pci_dev *dev, int mask)
+{
+ int ret;
+
+ ret = pcibios_enable_resources(dev, mask);
+ if (ret < 0)
+ return ret;
+
+ return acpi_pci_irq_enable(dev);
+}
+
+#ifdef CONFIG_ACPI_DEALLOCATE_IRQ
+void
+pcibios_disable_device (struct pci_dev *dev)
+{
+ acpi_pci_irq_disable(dev);
+}
+#endif /* CONFIG_ACPI_DEALLOCATE_IRQ */
+
+void
+pcibios_align_resource (void *data, struct resource *res,
+ unsigned long size, unsigned long align)
+{
+}
+
+/*
+ * PCI BIOS setup, always defaults to SAL interface
+ */
+char * __init
+pcibios_setup (char *str)
+{
+ if (!strcmp(str, "routeirq"))
+ pci_routeirq = 1;
+ return NULL;
+}
+
+int
+pci_mmap_page_range (struct pci_dev *dev, struct vm_area_struct *vma,
+ enum pci_mmap_state mmap_state, int write_combine)
+{
+ /*
+ * I/O space cannot be accessed via normal processor loads and
+ * stores on this platform.
+ */
+ if (mmap_state == pci_mmap_io)
+ /*
+ * XXX we could relax this for I/O spaces for which ACPI
+ * indicates that the space is 1-to-1 mapped. But at the
+ * moment, we don't support multiple PCI address spaces and
+ * the legacy I/O space is not 1-to-1 mapped, so this is moot.
+ */
+ return -EINVAL;
+
+ /*
+ * Leave vm_pgoff as-is, the PCI space address is the physical
+ * address on this platform.
+ */
+ vma->vm_flags |= (VM_SHM | VM_RESERVED | VM_IO);
+
+ if (write_combine && efi_range_is_wc(vma->vm_start,
+ vma->vm_end - vma->vm_start))
+ vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
+ else
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+ if (remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
+ vma->vm_end - vma->vm_start, vma->vm_page_prot))
+ return -EAGAIN;
+
+ return 0;
+}
+
+/**
+ * ia64_pci_get_legacy_mem - generic legacy mem routine
+ * @bus: bus to get legacy memory base address for
+ *
+ * Find the base of legacy memory for @bus. This is typically the first
+ * megabyte of bus address space for @bus or is simply 0 on platforms whose
+ * chipsets support legacy I/O and memory routing. Returns the base address
+ * or an error pointer if an error occurred.
+ *
+ * This is the ia64 generic version of this routine. Other platforms
+ * are free to override it with a machine vector.
+ */
+char *ia64_pci_get_legacy_mem(struct pci_bus *bus)
+{
+ return (char *)__IA64_UNCACHED_OFFSET;
+}
+
+/**
+ * pci_mmap_legacy_page_range - map legacy memory space to userland
+ * @bus: bus whose legacy space we're mapping
+ * @vma: vma passed in by mmap
+ *
+ * Map legacy memory space for this device back to userspace using a machine
+ * vector to get the base address.
+ */
+int
+pci_mmap_legacy_page_range(struct pci_bus *bus, struct vm_area_struct *vma)
+{
+ char *addr;
+
+ addr = pci_get_legacy_mem(bus);
+ if (IS_ERR(addr))
+ return PTR_ERR(addr);
+
+ vma->vm_pgoff += (unsigned long)addr >> PAGE_SHIFT;
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+ vma->vm_flags |= (VM_SHM | VM_RESERVED | VM_IO);
+
+ if (remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
+ vma->vm_end - vma->vm_start, vma->vm_page_prot))
+ return -EAGAIN;
+
+ return 0;
+}
+
+/**
+ * ia64_pci_legacy_read - read from legacy I/O space
+ * @bus: bus to read
+ * @port: legacy port value
+ * @val: caller allocated storage for returned value
+ * @size: number of bytes to read
+ *
+ * Simply reads @size bytes from @port and puts the result in @val.
+ *
+ * Again, this (and the write routine) are generic versions that can be
+ * overridden by the platform. This is necessary on platforms that don't
+ * support legacy I/O routing or that hard fail on legacy I/O timeouts.
+ */
+int ia64_pci_legacy_read(struct pci_bus *bus, u16 port, u32 *val, u8 size)
+{
+ int ret = size;
+
+ switch (size) {
+ case 1:
+ *val = inb(port);
+ break;
+ case 2:
+ *val = inw(port);
+ break;
+ case 4:
+ *val = inl(port);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+/**
+ * ia64_pci_legacy_write - perform a legacy I/O write
+ * @bus: bus pointer
+ * @port: port to write
+ * @val: value to write
+ * @size: number of bytes to write from @val
+ *
+ * Simply writes @size bytes of @val to @port.
+ */
+int ia64_pci_legacy_write(struct pci_dev *bus, u16 port, u32 val, u8 size)
+{
+ int ret = 0;
+
+ switch (size) {
+ case 1:
+ outb(val, port);
+ break;
+ case 2:
+ outw(val, port);
+ break;
+ case 4:
+ outl(val, port);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+/**
+ * pci_cacheline_size - determine cacheline size for PCI devices
+ * @dev: void
+ *
+ * We want to use the line-size of the outer-most cache. We assume
+ * that this line-size is the same for all CPUs.
+ *
+ * Code mostly taken from arch/ia64/kernel/palinfo.c:cache_info().
+ *
+ * RETURNS: An appropriate -ERRNO error value on eror, or zero for success.
+ */
+static unsigned long
+pci_cacheline_size (void)
+{
+ u64 levels, unique_caches;
+ s64 status;
+ pal_cache_config_info_t cci;
+ static u8 cacheline_size;
+
+ if (cacheline_size)
+ return cacheline_size;
+
+ status = ia64_pal_cache_summary(&levels, &unique_caches);
+ if (status != 0) {
+ printk(KERN_ERR "%s: ia64_pal_cache_summary() failed (status=%ld)\n",
+ __FUNCTION__, status);
+ return SMP_CACHE_BYTES;
+ }
+
+ status = ia64_pal_cache_config_info(levels - 1, /* cache_type (data_or_unified)= */ 2,
+ &cci);
+ if (status != 0) {
+ printk(KERN_ERR "%s: ia64_pal_cache_config_info() failed (status=%ld)\n",
+ __FUNCTION__, status);
+ return SMP_CACHE_BYTES;
+ }
+ cacheline_size = 1 << cci.pcci_line_size;
+ return cacheline_size;
+}
+
+/**
+ * pcibios_prep_mwi - helper function for drivers/pci/pci.c:pci_set_mwi()
+ * @dev: the PCI device for which MWI is enabled
+ *
+ * For ia64, we can get the cacheline sizes from PAL.
+ *
+ * RETURNS: An appropriate -ERRNO error value on eror, or zero for success.
+ */
+int
+pcibios_prep_mwi (struct pci_dev *dev)
+{
+ unsigned long desired_linesize, current_linesize;
+ int rc = 0;
+ u8 pci_linesize;
+
+ desired_linesize = pci_cacheline_size();
+
+ pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &pci_linesize);
+ current_linesize = 4 * pci_linesize;
+ if (desired_linesize != current_linesize) {
+ printk(KERN_WARNING "PCI: slot %s has incorrect PCI cache line size of %lu bytes,",
+ pci_name(dev), current_linesize);
+ if (current_linesize > desired_linesize) {
+ printk(" expected %lu bytes instead\n", desired_linesize);
+ rc = -EINVAL;
+ } else {
+ printk(" correcting to %lu\n", desired_linesize);
+ pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, desired_linesize / 4);
+ }
+ }
+ return rc;
+}
+
+int pci_vector_resources(int last, int nr_released)
+{
+ int count = nr_released;
+
+ count += (IA64_LAST_DEVICE_VECTOR - last);
+
+ return count;
+}