/*
* IBM PowerPC Virtual I/O Infrastructure Support.
*
* 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
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/types.h>
#include <linux/stat.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/console.h>
#include <linux/export.h>
#include <linux/mm.h>
#include <linux/dma-mapping.h>
#include <linux/kobject.h>
#include <asm/iommu.h>
#include <asm/dma.h>
#include <asm/vio.h>
#include <asm/prom.h>
#include <asm/firmware.h>
#include <asm/tce.h>
#include <asm/abs_addr.h>
#include <asm/page.h>
#include <asm/hvcall.h>
static struct bus_type vio_bus_type;
static struct vio_dev vio_bus_device = { /* fake "parent" device */
.name = "vio",
.type = "",
.dev.init_name = "vio",
.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 = min3(spare_needed, 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(to_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 dma_attrs *attrs)
{
struct vio_dev *viodev = to_vio_dev(dev);
void *ret;
if (vio_cmo_alloc(viodev, roundup(size, PAGE_SIZE))) {
atomic_inc(&viodev->cmo.allocs_failed);
return NULL;
}
ret = dma_iommu_ops.alloc(dev, size, dma_handle, flag, attrs);
if (unlikely(ret == NULL)) {
vio_cmo_dealloc(viodev, roundup(size, 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 dma_attrs *attrs)
{
struct vio_dev *viodev = to_vio_dev(dev);
dma_iommu_ops.free(dev, size, vaddr, dma_handle, attrs);
vio_cmo_dealloc(viodev, roundup(size, PAGE_SIZE));
}
static dma_addr_t vio_dma_iommu_map_page(struct device *dev, struct page *page,
unsigned long offset, 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_page(dev, page, offset, size, direction, attrs);
if (unlikely(dma_mapping_error(dev, ret))) {
vio_cmo_dealloc(viodev, roundup(size, IOMMU_PAGE_SIZE));
atomic_inc(&viodev->cmo.allocs_failed);
}
return ret;
}
static void vio_dma_iommu_unmap_page(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_page(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);
return ret;
}
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);
}
static int vio_dma_iommu_dma_supported(struct device *dev, u64 mask)
{
return dma_iommu_ops.dma_supported(dev, mask);
}
static u64 vio_dma_get_required_mask(struct device *dev)
{
return dma_iommu_ops.get_required_mask(dev);
}
struct dma_map_ops vio_dma_mapping_ops = {
.alloc = vio_dma_iommu_alloc_coherent,
.free = vio_dma_iommu_free_coherent,
.map_sg = vio_dma_iommu_map_sg,
.unmap_sg = vio_dma_iommu_unmap_sg,
.map_page = vio_dma_iommu_map_page,
.unmap_page = vio_dma_iommu_unmap_page,
.dma_supported = vio_dma_iommu_dma_supported,
.get_required_mask = vio_dma_get_required_mask,
};
/**
* 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) {
spin_unlock_irqrestore(&vio_cmo.lock, flags);
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.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)
{
set_dma_ops(&viodev->dev, &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 ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
char *buf);
static struct device_attribute vio_cmo_dev_attrs[] = {
__ATTR_RO(name),
__ATTR_RO(devspec),
__ATTR_RO(modalias),
__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 */
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(void) {}
static void vio_cmo_sysfs_init(void) { }
#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;
struct iommu_table *tbl;
unsigned long offset, size;
dma_window = of_get_property(dev->dev.of_node,
"ibm,my-dma-window", NULL);
if (!dma_window)
return NULL;
tbl = kzalloc(sizeof(*tbl), GFP_KERNEL);
if (tbl == NULL)
return NULL;
of_parse_dma_window(dev->dev.of_node, dma_window,
&tbl->it_index, &offset, &size);
/* TCE table size - measured in tce entries */
tbl->it_size = size >> IOMMU_PAGE_SHIFT;
/* offset for VIO should always be 0 */
tbl->it_offset = offset >> IOMMU_PAGE_SHIFT;
tbl->it_busno = 0;
tbl->it_type = TCE_VB;
tbl->it_blocksize = 16;
return iommu_init_table(tbl, -1);
}
/**
* vio_match_device: - Tell if a VIO device has a matching
* VIO device id structure.
* @ids: array of VIO device id structures to search in
* @dev: the VIO device structure to match against
*
* Used by a driver to check whether a VIO device present in the
* system is in its list of supported devices. Returns the matching
* vio_device_id structure or NULL if there is no match.
*/
static const struct vio_device_id *vio_match_device(
const struct vio_device_id *ids, const struct vio_dev *dev)
{
while (ids->type[0] != '\0') {
if ((strncmp(dev->type, ids->type, strlen(ids->type)) == 0) &&
of_device_is_compatible(dev->dev.of_node,
ids->compat))
return ids;
ids++;
}
return NULL;
}
/*
* Convert from struct device to struct vio_dev and pass to driver.
* dev->driver has already been set by generic code because vio_bus_match
* succeeded.
*/
static int vio_bus_probe(struct device *dev)
{
struct vio_dev *viodev = to_vio_dev(dev);
struct vio_driver *viodrv = to_vio_driver(dev->driver);
const struct vio_device_id *id;
int error = -ENODEV;
if (!viodrv->probe)
return error;
id = vio_match_device(viodrv->id_table, viodev);
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 && firmware_has_feature(FW_FEATURE_CMO))
vio_cmo_bus_remove(viodev);
}
return error;
}
/* convert from struct device to struct vio_dev and pass to driver. */
static int vio_bus_remove(struct device *dev)
{
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)
ret = viodrv->remove(viodev);
if (!ret && firmware_has_feature(FW_FEATURE_CMO))
vio_cmo_bus_remove(viodev);
put_device(devptr);
return ret;
}
/**
* vio_register_driver: - Register a new vio driver
* @drv: The vio_driver structure to be registered.
*/
int __vio_register_driver(struct vio_driver *viodrv, struct module *owner,
const char *mod_name)
{
pr_debug("%s: driver %s registering\n", __func__, viodrv->name);
/* fill in 'struct driver' fields */
viodrv->driver.name = viodrv->name;
viodrv->driver.pm = viodrv->pm;
viodrv->driver.bus = &vio_bus_type;
viodrv->driver.owner = owner;
viodrv->driver.mod_name = mod_name;
return driver_register(&viodrv->driver);
}
EXPORT_SYMBOL(__vio_register_driver);
/**
* vio_unregister_driver - Remove registration of vio driver.
* @driver: The vio_driver struct to be removed form registration
*/
void vio_unregister_driver(struct vio_driver *viodrv)
{
driver_unregister(&viodrv->driver);
}
EXPORT_SYMBOL(vio_unregister_driver);
/* vio_dev refcount hit 0 */
static void __devinit vio_dev_release(struct device *dev)
{
struct iommu_table *tbl = get_iommu_table_base(dev);
if (tbl)
iommu_free_table(tbl, dev->of_node ?
dev->of_node->full_name : dev_name(dev));
of_node_put(dev->of_node);
kfree(to_vio_dev(dev));
}
/**
* vio_register_device_node: - Register a new vio device.
* @of_node: The OF node for this device.
*
* Creates and initializes a vio_dev structure from the data in
* of_node and adds it to the list of virtual devices.
* Returns a pointer to the created vio_dev or NULL if node has
* NULL device_type or compatible fields.
*/
struct vio_dev *vio_register_device_node(struct device_node *of_node)
{
struct vio_dev *viodev;
const unsigned int *unit_address;
/* we need the 'device_type' property, in order to match with drivers */
if (of_node->type == NULL) {
printk(KERN_WARNING "%s: node %s missing 'device_type'\n",
__func__,
of_node->name ? of_node->name : "<unknown>");
return NULL;
}
unit_address = of_get_property(of_node, "reg", NULL);
if (unit_address == NULL) {
printk(KERN_WARNING "%s: node %s missing 'reg'\n",
__func__,
of_node->name ? of_node->name : "<unknown>");
return NULL;
}
/* allocate a vio_dev for this node */
viodev = kzalloc(sizeof(struct vio_dev), GFP_KERNEL);
if (viodev == NULL)
return NULL;
viodev->irq = irq_of_parse_and_map(of_node, 0);
dev_set_name(&viodev->dev, "%x", *unit_address);
viodev->name = of_node->name;
viodev->type = of_node->type;
viodev->unit_address = *unit_address;
viodev->dev.of_node = of_node_get(of_node);
if (firmware_has_feature(FW_FEATURE_CMO))
vio_cmo_set_dma_ops(viodev);
else
set_dma_ops(&viodev->dev, &dma_iommu_ops);
set_iommu_table_base(&viodev->dev, vio_build_iommu_table(viodev));
set_dev_node(&viodev->dev, of_node_to_nid(of_node));
/* init generic 'struct device' fields: */
viodev->dev.parent = &vio_bus_device.dev;
viodev->dev.bus = &vio_bus_type;
viodev->dev.release = vio_dev_release;
/* needed to ensure proper operation of coherent allocations
* later, in case driver doesn't set it explicitly */
dma_set_mask(&viodev->dev, DMA_BIT_MASK(64));
dma_set_coherent_mask(&viodev->dev, DMA_BIT_MASK(64));
/* register with generic device framework */
if (device_register(&viodev->dev)) {
printk(KERN_ERR "%s: failed to register device %s\n",
__func__, dev_name(&viodev->dev));
put_device(&viodev->dev);
return NULL;
}
return viodev;
}
EXPORT_SYMBOL(vio_register_device_node);
/**
* vio_bus_init: - Initialize the virtual IO bus
*/
static int __init vio_bus_init(void)
{
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;
}
/*
* The fake parent of all vio devices, just to give us
* a nice directory
*/
err = device_register(&vio_bus_device.dev);
if (err) {
printk(KERN_WARNING "%s: device_register returned %i\n",
__func__, err);
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;
/*
* Create struct vio_devices for each virtual device in
* the device tree. Drivers will associate with them later.
*/
for (of_node = node_vroot->child; of_node != NULL;
of_node = of_node->sibling)
vio_register_device_node(of_node);
of_node_put(node_vroot);
}
return 0;
}
__initcall(vio_bus_init);
static ssize_t name_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%s\n", to_vio_dev(dev)->name);
}
static ssize_t devspec_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct device_node *of_node = dev->of_node;
return sprintf(buf, "%s\n", of_node ? of_node->full_name : "none");
}
static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
const struct vio_dev *vio_dev = to_vio_dev(dev);
struct device_node *dn;
const char *cp;
dn = dev->of_node;
if (!dn)
return -ENODEV;
cp = of_get_property(dn, "compatible", NULL);
if (!cp)
return -ENODEV;
return sprintf(buf, "vio:T%sS%s\n", vio_dev->type, cp);
}
static struct device_attribute vio_dev_attrs[] = {
__ATTR_RO(name),
__ATTR_RO(devspec),
__ATTR_RO(modalias),
__ATTR_NULL
};
void __devinit vio_unregister_device(struct vio_dev *viodev)
{
device_unregister(&viodev->dev);
}
EXPORT_SYMBOL(vio_unregister_device);
static int vio_bus_match(struct device *dev, struct device_driver *drv)
{
const struct vio_dev *vio_dev = to_vio_dev(dev);
struct vio_driver *vio_drv = to_vio_driver(drv);
const struct vio_device_id *ids = vio_drv->id_table;
return (ids != NULL) && (vio_match_device(ids, vio_dev) != NULL);
}
static int vio_hotplug(struct device *dev, struct kobj_uevent_env *env)
{
const struct vio_dev *vio_dev = to_vio_dev(dev);
struct device_node *dn;
const char *cp;
dn = dev->of_node;
if (!dn)
return -ENODEV;
cp = of_get_property(dn, "compatible", NULL);
if (!cp)
return -ENODEV;
add_uevent_var(env, "MODALIAS=vio:T%sS%s", vio_dev->type, cp);
return 0;
}
static struct bus_type vio_bus_type = {
.name = "vio",
.dev_attrs = vio_dev_attrs,
.uevent = vio_hotplug,
.match = vio_bus_match,
.probe = vio_bus_probe,
.remove = vio_bus_remove,
};
/**
* vio_get_attribute: - get attribute for virtual device
* @vdev: The vio device to get property.
* @which: The property/attribute to be extracted.
* @length: Pointer to length of returned data size (unused if NULL).
*
* Calls prom.c's of_get_property() to return the value of the
* attribute specified by @which
*/
const void *vio_get_attribute(struct vio_dev *vdev, char *which, int *length)
{
return of_get_property(vdev->dev.of_node, which, length);
}
EXPORT_SYMBOL(vio_get_attribute);
#ifdef CONFIG_PPC_PSERIES
/* vio_find_name() - internal because only vio.c knows how we formatted the
* kobject name
*/
static struct vio_dev *vio_find_name(const char *name)
{
struct device *found;
found = bus_find_device_by_name(&vio_bus_type, NULL, name);
if (!found)
return NULL;
return to_vio_dev(found);
}
/**
* vio_find_node - find an already-registered vio_dev
* @vnode: device_node of the virtual device we're looking for
*/
struct vio_dev *vio_find_node(struct device_node *vnode)
{
const uint32_t *unit_address;
char kobj_name[20];
/* construct the kobject name from the device node */
unit_address = of_get_property(vnode, "reg", NULL);
if (!unit_address)
return NULL;
snprintf(kobj_name, sizeof(kobj_name), "%x", *unit_address);
return vio_find_name(kobj_name);
}
EXPORT_SYMBOL(vio_find_node);
int vio_enable_interrupts(struct vio_dev *dev)
{
int rc = h_vio_signal(dev->unit_address, VIO_IRQ_ENABLE);
if (rc != H_SUCCESS)
printk(KERN_ERR "vio: Error 0x%x enabling interrupts\n", rc);
return rc;
}
EXPORT_SYMBOL(vio_enable_interrupts);
int vio_disable_interrupts(struct vio_dev *dev)
{
int rc = h_vio_signal(dev->unit_address, VIO_IRQ_DISABLE);
if (rc != H_SUCCESS)
printk(KERN_ERR "vio: Error 0x%x disabling interrupts\n", rc);
return rc;
}
EXPORT_SYMBOL(vio_disable_interrupts);
#endif /* CONFIG_PPC_PSERIES */
