/*
* IBM PowerPC Virtual I/O Infrastructure Support.
*
- * Copyright (c) 2003-2005 IBM Corp.
+ * Copyright (c) 2003,2008 IBM Corp.
* Dave Engebretsen engebret@us.ibm.com
* Santiago Leon santil@us.ibm.com
* Hollis Blanchard <hollisb@us.ibm.com>
* Stephen Rothwell
+ * Robert Jennings <rcjenn@us.ibm.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
.dev.bus = &vio_bus_type,
};
+#ifdef CONFIG_PPC_SMLPAR
+/**
+ * vio_cmo_pool - A pool of IO memory for CMO use
+ *
+ * @size: The size of the pool in bytes
+ * @free: The amount of free memory in the pool
+ */
+struct vio_cmo_pool {
+ size_t size;
+ size_t free;
+};
+
+/* How many ms to delay queued balance work */
+#define VIO_CMO_BALANCE_DELAY 100
+
+/* Portion out IO memory to CMO devices by this chunk size */
+#define VIO_CMO_BALANCE_CHUNK 131072
+
+/**
+ * vio_cmo_dev_entry - A device that is CMO-enabled and requires entitlement
+ *
+ * @vio_dev: struct vio_dev pointer
+ * @list: pointer to other devices on bus that are being tracked
+ */
+struct vio_cmo_dev_entry {
+ struct vio_dev *viodev;
+ struct list_head list;
+};
+
+/**
+ * vio_cmo - VIO bus accounting structure for CMO entitlement
+ *
+ * @lock: spinlock for entire structure
+ * @balance_q: work queue for balancing system entitlement
+ * @device_list: list of CMO-enabled devices requiring entitlement
+ * @entitled: total system entitlement in bytes
+ * @reserve: pool of memory from which devices reserve entitlement, incl. spare
+ * @excess: pool of excess entitlement not needed for device reserves or spare
+ * @spare: IO memory for device hotplug functionality
+ * @min: minimum necessary for system operation
+ * @desired: desired memory for system operation
+ * @curr: bytes currently allocated
+ * @high: high water mark for IO data usage
+ */
+struct vio_cmo {
+ spinlock_t lock;
+ struct delayed_work balance_q;
+ struct list_head device_list;
+ size_t entitled;
+ struct vio_cmo_pool reserve;
+ struct vio_cmo_pool excess;
+ size_t spare;
+ size_t min;
+ size_t desired;
+ size_t curr;
+ size_t high;
+} vio_cmo;
+
+/**
+ * vio_cmo_OF_devices - Count the number of OF devices that have DMA windows
+ */
+static int vio_cmo_num_OF_devs(void)
+{
+ struct device_node *node_vroot;
+ int count = 0;
+
+ /*
+ * Count the number of vdevice entries with an
+ * ibm,my-dma-window OF property
+ */
+ node_vroot = of_find_node_by_name(NULL, "vdevice");
+ if (node_vroot) {
+ struct device_node *of_node;
+ struct property *prop;
+
+ for_each_child_of_node(node_vroot, of_node) {
+ prop = of_find_property(of_node, "ibm,my-dma-window",
+ NULL);
+ if (prop)
+ count++;
+ }
+ }
+ of_node_put(node_vroot);
+ return count;
+}
+
+/**
+ * vio_cmo_alloc - allocate IO memory for CMO-enable devices
+ *
+ * @viodev: VIO device requesting IO memory
+ * @size: size of allocation requested
+ *
+ * Allocations come from memory reserved for the devices and any excess
+ * IO memory available to all devices. The spare pool used to service
+ * hotplug must be equal to %VIO_CMO_MIN_ENT for the excess pool to be
+ * made available.
+ *
+ * Return codes:
+ * 0 for successful allocation and -ENOMEM for a failure
+ */
+static inline int vio_cmo_alloc(struct vio_dev *viodev, size_t size)
+{
+ unsigned long flags;
+ size_t reserve_free = 0;
+ size_t excess_free = 0;
+ int ret = -ENOMEM;
+
+ spin_lock_irqsave(&vio_cmo.lock, flags);
+
+ /* Determine the amount of free entitlement available in reserve */
+ if (viodev->cmo.entitled > viodev->cmo.allocated)
+ reserve_free = viodev->cmo.entitled - viodev->cmo.allocated;
+
+ /* If spare is not fulfilled, the excess pool can not be used. */
+ if (vio_cmo.spare >= VIO_CMO_MIN_ENT)
+ excess_free = vio_cmo.excess.free;
+
+ /* The request can be satisfied */
+ if ((reserve_free + excess_free) >= size) {
+ vio_cmo.curr += size;
+ if (vio_cmo.curr > vio_cmo.high)
+ vio_cmo.high = vio_cmo.curr;
+ viodev->cmo.allocated += size;
+ size -= min(reserve_free, size);
+ vio_cmo.excess.free -= size;
+ ret = 0;
+ }
+
+ spin_unlock_irqrestore(&vio_cmo.lock, flags);
+ return ret;
+}
+
+/**
+ * vio_cmo_dealloc - deallocate IO memory from CMO-enable devices
+ * @viodev: VIO device freeing IO memory
+ * @size: size of deallocation
+ *
+ * IO memory is freed by the device back to the correct memory pools.
+ * The spare pool is replenished first from either memory pool, then
+ * the reserve pool is used to reduce device entitlement, the excess
+ * pool is used to increase the reserve pool toward the desired entitlement
+ * target, and then the remaining memory is returned to the pools.
+ *
+ */
+static inline void vio_cmo_dealloc(struct vio_dev *viodev, size_t size)
+{
+ unsigned long flags;
+ size_t spare_needed = 0;
+ size_t excess_freed = 0;
+ size_t reserve_freed = size;
+ size_t tmp;
+ int balance = 0;
+
+ spin_lock_irqsave(&vio_cmo.lock, flags);
+ vio_cmo.curr -= size;
+
+ /* Amount of memory freed from the excess pool */
+ if (viodev->cmo.allocated > viodev->cmo.entitled) {
+ excess_freed = min(reserve_freed, (viodev->cmo.allocated -
+ viodev->cmo.entitled));
+ reserve_freed -= excess_freed;
+ }
+
+ /* Remove allocation from device */
+ viodev->cmo.allocated -= (reserve_freed + excess_freed);
+
+ /* Spare is a subset of the reserve pool, replenish it first. */
+ spare_needed = VIO_CMO_MIN_ENT - vio_cmo.spare;
+
+ /*
+ * Replenish the spare in the reserve pool from the excess pool.
+ * This moves entitlement into the reserve pool.
+ */
+ if (spare_needed && excess_freed) {
+ tmp = min(excess_freed, spare_needed);
+ vio_cmo.excess.size -= tmp;
+ vio_cmo.reserve.size += tmp;
+ vio_cmo.spare += tmp;
+ excess_freed -= tmp;
+ spare_needed -= tmp;
+ balance = 1;
+ }
+
+ /*
+ * Replenish the spare in the reserve pool from the reserve pool.
+ * This removes entitlement from the device down to VIO_CMO_MIN_ENT,
+ * if needed, and gives it to the spare pool. The amount of used
+ * memory in this pool does not change.
+ */
+ if (spare_needed && reserve_freed) {
+ tmp = min(spare_needed, min(reserve_freed,
+ (viodev->cmo.entitled -
+ VIO_CMO_MIN_ENT)));
+
+ vio_cmo.spare += tmp;
+ viodev->cmo.entitled -= tmp;
+ reserve_freed -= tmp;
+ spare_needed -= tmp;
+ balance = 1;
+ }
+
+ /*
+ * Increase the reserve pool until the desired allocation is met.
+ * Move an allocation freed from the excess pool into the reserve
+ * pool and schedule a balance operation.
+ */
+ if (excess_freed && (vio_cmo.desired > vio_cmo.reserve.size)) {
+ tmp = min(excess_freed, (vio_cmo.desired - vio_cmo.reserve.size));
+
+ vio_cmo.excess.size -= tmp;
+ vio_cmo.reserve.size += tmp;
+ excess_freed -= tmp;
+ balance = 1;
+ }
+
+ /* Return memory from the excess pool to that pool */
+ if (excess_freed)
+ vio_cmo.excess.free += excess_freed;
+
+ if (balance)
+ schedule_delayed_work(&vio_cmo.balance_q, VIO_CMO_BALANCE_DELAY);
+ spin_unlock_irqrestore(&vio_cmo.lock, flags);
+}
+
+/**
+ * vio_cmo_entitlement_update - Manage system entitlement changes
+ *
+ * @new_entitlement: new system entitlement to attempt to accommodate
+ *
+ * Increases in entitlement will be used to fulfill the spare entitlement
+ * and the rest is given to the excess pool. Decreases, if they are
+ * possible, come from the excess pool and from unused device entitlement
+ *
+ * Returns: 0 on success, -ENOMEM when change can not be made
+ */
+int vio_cmo_entitlement_update(size_t new_entitlement)
+{
+ struct vio_dev *viodev;
+ struct vio_cmo_dev_entry *dev_ent;
+ unsigned long flags;
+ size_t avail, delta, tmp;
+
+ spin_lock_irqsave(&vio_cmo.lock, flags);
+
+ /* Entitlement increases */
+ if (new_entitlement > vio_cmo.entitled) {
+ delta = new_entitlement - vio_cmo.entitled;
+
+ /* Fulfill spare allocation */
+ if (vio_cmo.spare < VIO_CMO_MIN_ENT) {
+ tmp = min(delta, (VIO_CMO_MIN_ENT - vio_cmo.spare));
+ vio_cmo.spare += tmp;
+ vio_cmo.reserve.size += tmp;
+ delta -= tmp;
+ }
+
+ /* Remaining new allocation goes to the excess pool */
+ vio_cmo.entitled += delta;
+ vio_cmo.excess.size += delta;
+ vio_cmo.excess.free += delta;
+
+ goto out;
+ }
+
+ /* Entitlement decreases */
+ delta = vio_cmo.entitled - new_entitlement;
+ avail = vio_cmo.excess.free;
+
+ /*
+ * Need to check how much unused entitlement each device can
+ * sacrifice to fulfill entitlement change.
+ */
+ list_for_each_entry(dev_ent, &vio_cmo.device_list, list) {
+ if (avail >= delta)
+ break;
+
+ viodev = dev_ent->viodev;
+ if ((viodev->cmo.entitled > viodev->cmo.allocated) &&
+ (viodev->cmo.entitled > VIO_CMO_MIN_ENT))
+ avail += viodev->cmo.entitled -
+ max_t(size_t, viodev->cmo.allocated,
+ VIO_CMO_MIN_ENT);
+ }
+
+ if (delta <= avail) {
+ vio_cmo.entitled -= delta;
+
+ /* Take entitlement from the excess pool first */
+ tmp = min(vio_cmo.excess.free, delta);
+ vio_cmo.excess.size -= tmp;
+ vio_cmo.excess.free -= tmp;
+ delta -= tmp;
+
+ /*
+ * Remove all but VIO_CMO_MIN_ENT bytes from devices
+ * until entitlement change is served
+ */
+ list_for_each_entry(dev_ent, &vio_cmo.device_list, list) {
+ if (!delta)
+ break;
+
+ viodev = dev_ent->viodev;
+ tmp = 0;
+ if ((viodev->cmo.entitled > viodev->cmo.allocated) &&
+ (viodev->cmo.entitled > VIO_CMO_MIN_ENT))
+ tmp = viodev->cmo.entitled -
+ max_t(size_t, viodev->cmo.allocated,
+ VIO_CMO_MIN_ENT);
+ viodev->cmo.entitled -= min(tmp, delta);
+ delta -= min(tmp, delta);
+ }
+ } else {
+ spin_unlock_irqrestore(&vio_cmo.lock, flags);
+ return -ENOMEM;
+ }
+
+out:
+ schedule_delayed_work(&vio_cmo.balance_q, 0);
+ spin_unlock_irqrestore(&vio_cmo.lock, flags);
+ return 0;
+}
+
+/**
+ * vio_cmo_balance - Balance entitlement among devices
+ *
+ * @work: work queue structure for this operation
+ *
+ * Any system entitlement above the minimum needed for devices, or
+ * already allocated to devices, can be distributed to the devices.
+ * The list of devices is iterated through to recalculate the desired
+ * entitlement level and to determine how much entitlement above the
+ * minimum entitlement is allocated to devices.
+ *
+ * Small chunks of the available entitlement are given to devices until
+ * their requirements are fulfilled or there is no entitlement left to give.
+ * Upon completion sizes of the reserve and excess pools are calculated.
+ *
+ * The system minimum entitlement level is also recalculated here.
+ * Entitlement will be reserved for devices even after vio_bus_remove to
+ * accommodate reloading the driver. The OF tree is walked to count the
+ * number of devices present and this will remove entitlement for devices
+ * that have actually left the system after having vio_bus_remove called.
+ */
+static void vio_cmo_balance(struct work_struct *work)
+{
+ struct vio_cmo *cmo;
+ struct vio_dev *viodev;
+ struct vio_cmo_dev_entry *dev_ent;
+ unsigned long flags;
+ size_t avail = 0, level, chunk, need;
+ int devcount = 0, fulfilled;
+
+ cmo = container_of(work, struct vio_cmo, balance_q.work);
+
+ spin_lock_irqsave(&vio_cmo.lock, flags);
+
+ /* Calculate minimum entitlement and fulfill spare */
+ cmo->min = vio_cmo_num_OF_devs() * VIO_CMO_MIN_ENT;
+ BUG_ON(cmo->min > cmo->entitled);
+ cmo->spare = min_t(size_t, VIO_CMO_MIN_ENT, (cmo->entitled - cmo->min));
+ cmo->min += cmo->spare;
+ cmo->desired = cmo->min;
+
+ /*
+ * Determine how much entitlement is available and reset device
+ * entitlements
+ */
+ avail = cmo->entitled - cmo->spare;
+ list_for_each_entry(dev_ent, &vio_cmo.device_list, list) {
+ viodev = dev_ent->viodev;
+ devcount++;
+ viodev->cmo.entitled = VIO_CMO_MIN_ENT;
+ cmo->desired += (viodev->cmo.desired - VIO_CMO_MIN_ENT);
+ avail -= max_t(size_t, viodev->cmo.allocated, VIO_CMO_MIN_ENT);
+ }
+
+ /*
+ * Having provided each device with the minimum entitlement, loop
+ * over the devices portioning out the remaining entitlement
+ * until there is nothing left.
+ */
+ level = VIO_CMO_MIN_ENT;
+ while (avail) {
+ fulfilled = 0;
+ list_for_each_entry(dev_ent, &vio_cmo.device_list, list) {
+ viodev = dev_ent->viodev;
+
+ if (viodev->cmo.desired <= level) {
+ fulfilled++;
+ continue;
+ }
+
+ /*
+ * Give the device up to VIO_CMO_BALANCE_CHUNK
+ * bytes of entitlement, but do not exceed the
+ * desired level of entitlement for the device.
+ */
+ chunk = min_t(size_t, avail, VIO_CMO_BALANCE_CHUNK);
+ chunk = min(chunk, (viodev->cmo.desired -
+ viodev->cmo.entitled));
+ viodev->cmo.entitled += chunk;
+
+ /*
+ * If the memory for this entitlement increase was
+ * already allocated to the device it does not come
+ * from the available pool being portioned out.
+ */
+ need = max(viodev->cmo.allocated, viodev->cmo.entitled)-
+ max(viodev->cmo.allocated, level);
+ avail -= need;
+
+ }
+ if (fulfilled == devcount)
+ break;
+ level += VIO_CMO_BALANCE_CHUNK;
+ }
+
+ /* Calculate new reserve and excess pool sizes */
+ cmo->reserve.size = cmo->min;
+ cmo->excess.free = 0;
+ cmo->excess.size = 0;
+ need = 0;
+ list_for_each_entry(dev_ent, &vio_cmo.device_list, list) {
+ viodev = dev_ent->viodev;
+ /* Calculated reserve size above the minimum entitlement */
+ if (viodev->cmo.entitled)
+ cmo->reserve.size += (viodev->cmo.entitled -
+ VIO_CMO_MIN_ENT);
+ /* Calculated used excess entitlement */
+ if (viodev->cmo.allocated > viodev->cmo.entitled)
+ need += viodev->cmo.allocated - viodev->cmo.entitled;
+ }
+ cmo->excess.size = cmo->entitled - cmo->reserve.size;
+ cmo->excess.free = cmo->excess.size - need;
+
+ cancel_delayed_work(container_of(work, struct delayed_work, work));
+ spin_unlock_irqrestore(&vio_cmo.lock, flags);
+}
+
+static void *vio_dma_iommu_alloc_coherent(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t flag)
+{
+ struct vio_dev *viodev = to_vio_dev(dev);
+ void *ret;
+
+ if (vio_cmo_alloc(viodev, roundup(size, IOMMU_PAGE_SIZE))) {
+ atomic_inc(&viodev->cmo.allocs_failed);
+ return NULL;
+ }
+
+ ret = dma_iommu_ops.alloc_coherent(dev, size, dma_handle, flag);
+ if (unlikely(ret == NULL)) {
+ vio_cmo_dealloc(viodev, roundup(size, IOMMU_PAGE_SIZE));
+ atomic_inc(&viodev->cmo.allocs_failed);
+ }
+
+ return ret;
+}
+
+static void vio_dma_iommu_free_coherent(struct device *dev, size_t size,
+ void *vaddr, dma_addr_t dma_handle)
+{
+ struct vio_dev *viodev = to_vio_dev(dev);
+
+ dma_iommu_ops.free_coherent(dev, size, vaddr, dma_handle);
+
+ vio_cmo_dealloc(viodev, roundup(size, IOMMU_PAGE_SIZE));
+}
+
+static dma_addr_t vio_dma_iommu_map_single(struct device *dev, void *vaddr,
+ size_t size,
+ enum dma_data_direction direction,
+ struct dma_attrs *attrs)
+{
+ struct vio_dev *viodev = to_vio_dev(dev);
+ dma_addr_t ret = DMA_ERROR_CODE;
+
+ if (vio_cmo_alloc(viodev, roundup(size, IOMMU_PAGE_SIZE))) {
+ atomic_inc(&viodev->cmo.allocs_failed);
+ return ret;
+ }
+
+ ret = dma_iommu_ops.map_single(dev, vaddr, size, direction, attrs);
+ if (unlikely(dma_mapping_error(ret))) {
+ vio_cmo_dealloc(viodev, roundup(size, IOMMU_PAGE_SIZE));
+ atomic_inc(&viodev->cmo.allocs_failed);
+ }
+
+ return ret;
+}
+
+static void vio_dma_iommu_unmap_single(struct device *dev,
+ dma_addr_t dma_handle, size_t size,
+ enum dma_data_direction direction,
+ struct dma_attrs *attrs)
+{
+ struct vio_dev *viodev = to_vio_dev(dev);
+
+ dma_iommu_ops.unmap_single(dev, dma_handle, size, direction, attrs);
+
+ vio_cmo_dealloc(viodev, roundup(size, IOMMU_PAGE_SIZE));
+}
+
+static int vio_dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist,
+ int nelems, enum dma_data_direction direction,
+ struct dma_attrs *attrs)
+{
+ struct vio_dev *viodev = to_vio_dev(dev);
+ struct scatterlist *sgl;
+ int ret, count = 0;
+ size_t alloc_size = 0;
+
+ for (sgl = sglist; count < nelems; count++, sgl++)
+ alloc_size += roundup(sgl->length, IOMMU_PAGE_SIZE);
+
+ if (vio_cmo_alloc(viodev, alloc_size)) {
+ atomic_inc(&viodev->cmo.allocs_failed);
+ return 0;
+ }
+
+ ret = dma_iommu_ops.map_sg(dev, sglist, nelems, direction, attrs);
+
+ if (unlikely(!ret)) {
+ vio_cmo_dealloc(viodev, alloc_size);
+ atomic_inc(&viodev->cmo.allocs_failed);
+ }
+
+ for (sgl = sglist, count = 0; count < ret; count++, sgl++)
+ alloc_size -= roundup(sgl->dma_length, IOMMU_PAGE_SIZE);
+ if (alloc_size)
+ vio_cmo_dealloc(viodev, alloc_size);
+
+ return ret;
+}
+
+static void vio_dma_iommu_unmap_sg(struct device *dev,
+ struct scatterlist *sglist, int nelems,
+ enum dma_data_direction direction,
+ struct dma_attrs *attrs)
+{
+ struct vio_dev *viodev = to_vio_dev(dev);
+ struct scatterlist *sgl;
+ size_t alloc_size = 0;
+ int count = 0;
+
+ for (sgl = sglist; count < nelems; count++, sgl++)
+ alloc_size += roundup(sgl->dma_length, IOMMU_PAGE_SIZE);
+
+ dma_iommu_ops.unmap_sg(dev, sglist, nelems, direction, attrs);
+
+ vio_cmo_dealloc(viodev, alloc_size);
+}
+
+struct dma_mapping_ops vio_dma_mapping_ops = {
+ .alloc_coherent = vio_dma_iommu_alloc_coherent,
+ .free_coherent = vio_dma_iommu_free_coherent,
+ .map_single = vio_dma_iommu_map_single,
+ .unmap_single = vio_dma_iommu_unmap_single,
+ .map_sg = vio_dma_iommu_map_sg,
+ .unmap_sg = vio_dma_iommu_unmap_sg,
+};
+
+/**
+ * vio_cmo_set_dev_desired - Set desired entitlement for a device
+ *
+ * @viodev: struct vio_dev for device to alter
+ * @new_desired: new desired entitlement level in bytes
+ *
+ * For use by devices to request a change to their entitlement at runtime or
+ * through sysfs. The desired entitlement level is changed and a balancing
+ * of system resources is scheduled to run in the future.
+ */
+void vio_cmo_set_dev_desired(struct vio_dev *viodev, size_t desired)
+{
+ unsigned long flags;
+ struct vio_cmo_dev_entry *dev_ent;
+ int found = 0;
+
+ if (!firmware_has_feature(FW_FEATURE_CMO))
+ return;
+
+ spin_lock_irqsave(&vio_cmo.lock, flags);
+ if (desired < VIO_CMO_MIN_ENT)
+ desired = VIO_CMO_MIN_ENT;
+
+ /*
+ * Changes will not be made for devices not in the device list.
+ * If it is not in the device list, then no driver is loaded
+ * for the device and it can not receive entitlement.
+ */
+ list_for_each_entry(dev_ent, &vio_cmo.device_list, list)
+ if (viodev == dev_ent->viodev) {
+ found = 1;
+ break;
+ }
+ if (!found)
+ return;
+
+ /* Increase/decrease in desired device entitlement */
+ if (desired >= viodev->cmo.desired) {
+ /* Just bump the bus and device values prior to a balance*/
+ vio_cmo.desired += desired - viodev->cmo.desired;
+ viodev->cmo.desired = desired;
+ } else {
+ /* Decrease bus and device values for desired entitlement */
+ vio_cmo.desired -= viodev->cmo.desired - desired;
+ viodev->cmo.desired = desired;
+ /*
+ * If less entitlement is desired than current entitlement, move
+ * any reserve memory in the change region to the excess pool.
+ */
+ if (viodev->cmo.entitled > desired) {
+ vio_cmo.reserve.size -= viodev->cmo.entitled - desired;
+ vio_cmo.excess.size += viodev->cmo.entitled - desired;
+ /*
+ * If entitlement moving from the reserve pool to the
+ * excess pool is currently unused, add to the excess
+ * free counter.
+ */
+ if (viodev->cmo.allocated < viodev->cmo.entitled)
+ vio_cmo.excess.free += viodev->cmo.entitled -
+ max(viodev->cmo.allocated, desired);
+ viodev->cmo.entitled = desired;
+ }
+ }
+ schedule_delayed_work(&vio_cmo.balance_q, 0);
+ spin_unlock_irqrestore(&vio_cmo.lock, flags);
+}
+
+/**
+ * vio_cmo_bus_probe - Handle CMO specific bus probe activities
+ *
+ * @viodev - Pointer to struct vio_dev for device
+ *
+ * Determine the devices IO memory entitlement needs, attempting
+ * to satisfy the system minimum entitlement at first and scheduling
+ * a balance operation to take care of the rest at a later time.
+ *
+ * Returns: 0 on success, -EINVAL when device doesn't support CMO, and
+ * -ENOMEM when entitlement is not available for device or
+ * device entry.
+ *
+ */
+static int vio_cmo_bus_probe(struct vio_dev *viodev)
+{
+ struct vio_cmo_dev_entry *dev_ent;
+ struct device *dev = &viodev->dev;
+ struct vio_driver *viodrv = to_vio_driver(dev->driver);
+ unsigned long flags;
+ size_t size;
+
+ /*
+ * Check to see that device has a DMA window and configure
+ * entitlement for the device.
+ */
+ if (of_get_property(viodev->dev.archdata.of_node,
+ "ibm,my-dma-window", NULL)) {
+ /* Check that the driver is CMO enabled and get desired DMA */
+ if (!viodrv->get_desired_dma) {
+ dev_err(dev, "%s: device driver does not support CMO\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ viodev->cmo.desired = IOMMU_PAGE_ALIGN(viodrv->get_desired_dma(viodev));
+ if (viodev->cmo.desired < VIO_CMO_MIN_ENT)
+ viodev->cmo.desired = VIO_CMO_MIN_ENT;
+ size = VIO_CMO_MIN_ENT;
+
+ dev_ent = kmalloc(sizeof(struct vio_cmo_dev_entry),
+ GFP_KERNEL);
+ if (!dev_ent)
+ return -ENOMEM;
+
+ dev_ent->viodev = viodev;
+ spin_lock_irqsave(&vio_cmo.lock, flags);
+ list_add(&dev_ent->list, &vio_cmo.device_list);
+ } else {
+ viodev->cmo.desired = 0;
+ size = 0;
+ spin_lock_irqsave(&vio_cmo.lock, flags);
+ }
+
+ /*
+ * If the needs for vio_cmo.min have not changed since they
+ * were last set, the number of devices in the OF tree has
+ * been constant and the IO memory for this is already in
+ * the reserve pool.
+ */
+ if (vio_cmo.min == ((vio_cmo_num_OF_devs() + 1) *
+ VIO_CMO_MIN_ENT)) {
+ /* Updated desired entitlement if device requires it */
+ if (size)
+ vio_cmo.desired += (viodev->cmo.desired -
+ VIO_CMO_MIN_ENT);
+ } else {
+ size_t tmp;
+
+ tmp = vio_cmo.spare + vio_cmo.excess.free;
+ if (tmp < size) {
+ dev_err(dev, "%s: insufficient free "
+ "entitlement to add device. "
+ "Need %lu, have %lu\n", __func__,
+ size, (vio_cmo.spare + tmp));
+ spin_unlock_irqrestore(&vio_cmo.lock, flags);
+ return -ENOMEM;
+ }
+
+ /* Use excess pool first to fulfill request */
+ tmp = min(size, vio_cmo.excess.free);
+ vio_cmo.excess.free -= tmp;
+ vio_cmo.excess.size -= tmp;
+ vio_cmo.reserve.size += tmp;
+
+ /* Use spare if excess pool was insufficient */
+ vio_cmo.spare -= size - tmp;
+
+ /* Update bus accounting */
+ vio_cmo.min += size;
+ vio_cmo.desired += viodev->cmo.desired;
+ }
+ spin_unlock_irqrestore(&vio_cmo.lock, flags);
+ return 0;
+}
+
+/**
+ * vio_cmo_bus_remove - Handle CMO specific bus removal activities
+ *
+ * @viodev - Pointer to struct vio_dev for device
+ *
+ * Remove the device from the cmo device list. The minimum entitlement
+ * will be reserved for the device as long as it is in the system. The
+ * rest of the entitlement the device had been allocated will be returned
+ * to the system.
+ */
+static void vio_cmo_bus_remove(struct vio_dev *viodev)
+{
+ struct vio_cmo_dev_entry *dev_ent;
+ unsigned long flags;
+ size_t tmp;
+
+ spin_lock_irqsave(&vio_cmo.lock, flags);
+ if (viodev->cmo.allocated) {
+ dev_err(&viodev->dev, "%s: device had %lu bytes of IO "
+ "allocated after remove operation.\n",
+ __func__, viodev->cmo.allocated);
+ BUG();
+ }
+
+ /*
+ * Remove the device from the device list being maintained for
+ * CMO enabled devices.
+ */
+ list_for_each_entry(dev_ent, &vio_cmo.device_list, list)
+ if (viodev == dev_ent->viodev) {
+ list_del(&dev_ent->list);
+ kfree(dev_ent);
+ break;
+ }
+
+ /*
+ * Devices may not require any entitlement and they do not need
+ * to be processed. Otherwise, return the device's entitlement
+ * back to the pools.
+ */
+ if (viodev->cmo.entitled) {
+ /*
+ * This device has not yet left the OF tree, it's
+ * minimum entitlement remains in vio_cmo.min and
+ * vio_cmo.desired
+ */
+ vio_cmo.desired -= (viodev->cmo.desired - VIO_CMO_MIN_ENT);
+
+ /*
+ * Save min allocation for device in reserve as long
+ * as it exists in OF tree as determined by later
+ * balance operation
+ */
+ viodev->cmo.entitled -= VIO_CMO_MIN_ENT;
+
+ /* Replenish spare from freed reserve pool */
+ if (viodev->cmo.entitled && (vio_cmo.spare < VIO_CMO_MIN_ENT)) {
+ tmp = min(viodev->cmo.entitled, (VIO_CMO_MIN_ENT -
+ vio_cmo.spare));
+ vio_cmo.spare += tmp;
+ viodev->cmo.entitled -= tmp;
+ }
+
+ /* Remaining reserve goes to excess pool */
+ vio_cmo.excess.size += viodev->cmo.entitled;
+ vio_cmo.excess.free += viodev->cmo.entitled;
+ vio_cmo.reserve.size -= viodev->cmo.entitled;
+
+ /*
+ * Until the device is removed it will keep a
+ * minimum entitlement; this will guarantee that
+ * a module unload/load will result in a success.
+ */
+ viodev->cmo.entitled = VIO_CMO_MIN_ENT;
+ viodev->cmo.desired = VIO_CMO_MIN_ENT;
+ atomic_set(&viodev->cmo.allocs_failed, 0);
+ }
+
+ spin_unlock_irqrestore(&vio_cmo.lock, flags);
+}
+
+static void vio_cmo_set_dma_ops(struct vio_dev *viodev)
+{
+ vio_dma_mapping_ops.dma_supported = dma_iommu_ops.dma_supported;
+ viodev->dev.archdata.dma_ops = &vio_dma_mapping_ops;
+}
+
+/**
+ * vio_cmo_bus_init - CMO entitlement initialization at bus init time
+ *
+ * Set up the reserve and excess entitlement pools based on available
+ * system entitlement and the number of devices in the OF tree that
+ * require entitlement in the reserve pool.
+ */
+static void vio_cmo_bus_init(void)
+{
+ struct hvcall_mpp_data mpp_data;
+ int err;
+
+ memset(&vio_cmo, 0, sizeof(struct vio_cmo));
+ spin_lock_init(&vio_cmo.lock);
+ INIT_LIST_HEAD(&vio_cmo.device_list);
+ INIT_DELAYED_WORK(&vio_cmo.balance_q, vio_cmo_balance);
+
+ /* Get current system entitlement */
+ err = h_get_mpp(&mpp_data);
+
+ /*
+ * On failure, continue with entitlement set to 0, will panic()
+ * later when spare is reserved.
+ */
+ if (err != H_SUCCESS) {
+ printk(KERN_ERR "%s: unable to determine system IO "\
+ "entitlement. (%d)\n", __func__, err);
+ vio_cmo.entitled = 0;
+ } else {
+ vio_cmo.entitled = mpp_data.entitled_mem;
+ }
+
+ /* Set reservation and check against entitlement */
+ vio_cmo.spare = VIO_CMO_MIN_ENT;
+ vio_cmo.reserve.size = vio_cmo.spare;
+ vio_cmo.reserve.size += (vio_cmo_num_OF_devs() *
+ VIO_CMO_MIN_ENT);
+ if (vio_cmo.reserve.size > vio_cmo.entitled) {
+ printk(KERN_ERR "%s: insufficient system entitlement\n",
+ __func__);
+ panic("%s: Insufficient system entitlement", __func__);
+ }
+
+ /* Set the remaining accounting variables */
+ vio_cmo.excess.size = vio_cmo.entitled - vio_cmo.reserve.size;
+ vio_cmo.excess.free = vio_cmo.excess.size;
+ vio_cmo.min = vio_cmo.reserve.size;
+ vio_cmo.desired = vio_cmo.reserve.size;
+}
+
+/* sysfs device functions and data structures for CMO */
+
+#define viodev_cmo_rd_attr(name) \
+static ssize_t viodev_cmo_##name##_show(struct device *dev, \
+ struct device_attribute *attr, \
+ char *buf) \
+{ \
+ return sprintf(buf, "%lu\n", to_vio_dev(dev)->cmo.name); \
+}
+
+static ssize_t viodev_cmo_allocs_failed_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct vio_dev *viodev = to_vio_dev(dev);
+ return sprintf(buf, "%d\n", atomic_read(&viodev->cmo.allocs_failed));
+}
+
+static ssize_t viodev_cmo_allocs_failed_reset(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct vio_dev *viodev = to_vio_dev(dev);
+ atomic_set(&viodev->cmo.allocs_failed, 0);
+ return count;
+}
+
+static ssize_t viodev_cmo_desired_set(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct vio_dev *viodev = to_vio_dev(dev);
+ size_t new_desired;
+ int ret;
+
+ ret = strict_strtoul(buf, 10, &new_desired);
+ if (ret)
+ return ret;
+
+ vio_cmo_set_dev_desired(viodev, new_desired);
+ return count;
+}
+
+viodev_cmo_rd_attr(desired);
+viodev_cmo_rd_attr(entitled);
+viodev_cmo_rd_attr(allocated);
+
+static ssize_t name_show(struct device *, struct device_attribute *, char *);
+static ssize_t devspec_show(struct device *, struct device_attribute *, char *);
+static struct device_attribute vio_cmo_dev_attrs[] = {
+ __ATTR_RO(name),
+ __ATTR_RO(devspec),
+ __ATTR(cmo_desired, S_IWUSR|S_IRUSR|S_IWGRP|S_IRGRP|S_IROTH,
+ viodev_cmo_desired_show, viodev_cmo_desired_set),
+ __ATTR(cmo_entitled, S_IRUGO, viodev_cmo_entitled_show, NULL),
+ __ATTR(cmo_allocated, S_IRUGO, viodev_cmo_allocated_show, NULL),
+ __ATTR(cmo_allocs_failed, S_IWUSR|S_IRUSR|S_IWGRP|S_IRGRP|S_IROTH,
+ viodev_cmo_allocs_failed_show, viodev_cmo_allocs_failed_reset),
+ __ATTR_NULL
+};
+
+/* sysfs bus functions and data structures for CMO */
+
+#define viobus_cmo_rd_attr(name) \
+static ssize_t \
+viobus_cmo_##name##_show(struct bus_type *bt, char *buf) \
+{ \
+ return sprintf(buf, "%lu\n", vio_cmo.name); \
+}
+
+#define viobus_cmo_pool_rd_attr(name, var) \
+static ssize_t \
+viobus_cmo_##name##_pool_show_##var(struct bus_type *bt, char *buf) \
+{ \
+ return sprintf(buf, "%lu\n", vio_cmo.name.var); \
+}
+
+static ssize_t viobus_cmo_high_reset(struct bus_type *bt, const char *buf,
+ size_t count)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&vio_cmo.lock, flags);
+ vio_cmo.high = vio_cmo.curr;
+ spin_unlock_irqrestore(&vio_cmo.lock, flags);
+
+ return count;
+}
+
+viobus_cmo_rd_attr(entitled);
+viobus_cmo_pool_rd_attr(reserve, size);
+viobus_cmo_pool_rd_attr(excess, size);
+viobus_cmo_pool_rd_attr(excess, free);
+viobus_cmo_rd_attr(spare);
+viobus_cmo_rd_attr(min);
+viobus_cmo_rd_attr(desired);
+viobus_cmo_rd_attr(curr);
+viobus_cmo_rd_attr(high);
+
+static struct bus_attribute vio_cmo_bus_attrs[] = {
+ __ATTR(cmo_entitled, S_IRUGO, viobus_cmo_entitled_show, NULL),
+ __ATTR(cmo_reserve_size, S_IRUGO, viobus_cmo_reserve_pool_show_size, NULL),
+ __ATTR(cmo_excess_size, S_IRUGO, viobus_cmo_excess_pool_show_size, NULL),
+ __ATTR(cmo_excess_free, S_IRUGO, viobus_cmo_excess_pool_show_free, NULL),
+ __ATTR(cmo_spare, S_IRUGO, viobus_cmo_spare_show, NULL),
+ __ATTR(cmo_min, S_IRUGO, viobus_cmo_min_show, NULL),
+ __ATTR(cmo_desired, S_IRUGO, viobus_cmo_desired_show, NULL),
+ __ATTR(cmo_curr, S_IRUGO, viobus_cmo_curr_show, NULL),
+ __ATTR(cmo_high, S_IWUSR|S_IRUSR|S_IWGRP|S_IRGRP|S_IROTH,
+ viobus_cmo_high_show, viobus_cmo_high_reset),
+ __ATTR_NULL
+};
+
+static void vio_cmo_sysfs_init(void)
+{
+ vio_bus_type.dev_attrs = vio_cmo_dev_attrs;
+ vio_bus_type.bus_attrs = vio_cmo_bus_attrs;
+}
+#else /* CONFIG_PPC_SMLPAR */
+/* Dummy functions for iSeries platform */
+int vio_cmo_entitlement_update(size_t new_entitlement) { return 0; }
+void vio_cmo_set_dev_desired(struct vio_dev *viodev, size_t desired) {}
+static int vio_cmo_bus_probe(struct vio_dev *viodev) { return 0; }
+static void vio_cmo_bus_remove(struct vio_dev *viodev) {}
+static void vio_cmo_set_dma_ops(struct vio_dev *viodev) {}
+static void vio_cmo_bus_init() {}
+static void vio_cmo_sysfs_init() { }
+#endif /* CONFIG_PPC_SMLPAR */
+EXPORT_SYMBOL(vio_cmo_entitlement_update);
+EXPORT_SYMBOL(vio_cmo_set_dev_desired);
+
static struct iommu_table *vio_build_iommu_table(struct vio_dev *dev)
{
const unsigned char *dma_window;
return error;
id = vio_match_device(viodrv->id_table, viodev);
- if (id)
+ if (id) {
+ memset(&viodev->cmo, 0, sizeof(viodev->cmo));
+ if (firmware_has_feature(FW_FEATURE_CMO)) {
+ error = vio_cmo_bus_probe(viodev);
+ if (error)
+ return error;
+ }
error = viodrv->probe(viodev, id);
+ if (error)
+ vio_cmo_bus_remove(viodev);
+ }
return error;
}
{
struct vio_dev *viodev = to_vio_dev(dev);
struct vio_driver *viodrv = to_vio_driver(dev->driver);
+ struct device *devptr;
+ int ret = 1;
+
+ /*
+ * Hold a reference to the device after the remove function is called
+ * to allow for CMO accounting cleanup for the device.
+ */
+ devptr = get_device(dev);
if (viodrv->remove)
- return viodrv->remove(viodev);
+ ret = viodrv->remove(viodev);
+
+ if (!ret && firmware_has_feature(FW_FEATURE_CMO))
+ vio_cmo_bus_remove(viodev);
- /* driver can't remove */
- return 1;
+ put_device(devptr);
+ return ret;
}
/**
viodev->unit_address = *unit_address;
}
viodev->dev.archdata.of_node = of_node_get(of_node);
- viodev->dev.archdata.dma_ops = &dma_iommu_ops;
+
+ if (firmware_has_feature(FW_FEATURE_CMO))
+ vio_cmo_set_dma_ops(viodev);
+ else
+ viodev->dev.archdata.dma_ops = &dma_iommu_ops;
viodev->dev.archdata.dma_data = vio_build_iommu_table(viodev);
viodev->dev.archdata.numa_node = of_node_to_nid(of_node);
int err;
struct device_node *node_vroot;
+ if (firmware_has_feature(FW_FEATURE_CMO))
+ vio_cmo_sysfs_init();
+
err = bus_register(&vio_bus_type);
if (err) {
printk(KERN_ERR "failed to register VIO bus\n");
return err;
}
+ if (firmware_has_feature(FW_FEATURE_CMO))
+ vio_cmo_bus_init();
+
node_vroot = of_find_node_by_name(NULL, "vdevice");
if (node_vroot) {
struct device_node *of_node;
projects / GitHub / mt8127 / android_kernel_alcatel_ttab.git / commitdiff