linux-stable/drivers/dma/idxd/dma.c
Dave Jiang 403a2e2365 dmaengine: idxd: change MSIX allocation based on per wq activation
Change the driver where WQ interrupt is requested only when wq is being
enabled. This new scheme set things up so that request_threaded_irq() is
only called when a kernel wq type is being enabled. This also sets up for
future interrupt request where different interrupt handler such as wq
occupancy interrupt can be setup instead of the wq completion interrupt.

Not calling request_irq() until the WQ actually needs an irq also prevents
wasting of CPU irq vectors on x86 systems, which is a limited resource.

idxd_flush_pending_descs() is moved to device.c since descriptor flushing
is now part of wq disable rather than shutdown().

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163942149487.2412839.6691222855803875848.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-01-05 13:11:22 +05:30

373 lines
8.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 2019 Intel Corporation. All rights rsvd. */
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/device.h>
#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/dmaengine.h>
#include <uapi/linux/idxd.h>
#include "../dmaengine.h"
#include "registers.h"
#include "idxd.h"
static inline struct idxd_wq *to_idxd_wq(struct dma_chan *c)
{
struct idxd_dma_chan *idxd_chan;
idxd_chan = container_of(c, struct idxd_dma_chan, chan);
return idxd_chan->wq;
}
void idxd_dma_complete_txd(struct idxd_desc *desc,
enum idxd_complete_type comp_type,
bool free_desc)
{
struct idxd_device *idxd = desc->wq->idxd;
struct dma_async_tx_descriptor *tx;
struct dmaengine_result res;
int complete = 1;
if (desc->completion->status == DSA_COMP_SUCCESS) {
res.result = DMA_TRANS_NOERROR;
} else if (desc->completion->status) {
if (idxd->request_int_handles && comp_type != IDXD_COMPLETE_ABORT &&
desc->completion->status == DSA_COMP_INT_HANDLE_INVAL &&
idxd_queue_int_handle_resubmit(desc))
return;
res.result = DMA_TRANS_WRITE_FAILED;
} else if (comp_type == IDXD_COMPLETE_ABORT) {
res.result = DMA_TRANS_ABORTED;
} else {
complete = 0;
}
tx = &desc->txd;
if (complete && tx->cookie) {
dma_cookie_complete(tx);
dma_descriptor_unmap(tx);
dmaengine_desc_get_callback_invoke(tx, &res);
tx->callback = NULL;
tx->callback_result = NULL;
}
if (free_desc)
idxd_free_desc(desc->wq, desc);
}
static void op_flag_setup(unsigned long flags, u32 *desc_flags)
{
*desc_flags = IDXD_OP_FLAG_CRAV | IDXD_OP_FLAG_RCR;
if (flags & DMA_PREP_INTERRUPT)
*desc_flags |= IDXD_OP_FLAG_RCI;
}
static inline void set_completion_address(struct idxd_desc *desc,
u64 *compl_addr)
{
*compl_addr = desc->compl_dma;
}
static inline void idxd_prep_desc_common(struct idxd_wq *wq,
struct dsa_hw_desc *hw, char opcode,
u64 addr_f1, u64 addr_f2, u64 len,
u64 compl, u32 flags)
{
hw->flags = flags;
hw->opcode = opcode;
hw->src_addr = addr_f1;
hw->dst_addr = addr_f2;
hw->xfer_size = len;
/*
* For dedicated WQ, this field is ignored and HW will use the WQCFG.priv
* field instead. This field should be set to 1 for kernel descriptors.
*/
hw->priv = 1;
hw->completion_addr = compl;
}
static struct dma_async_tx_descriptor *
idxd_dma_submit_memcpy(struct dma_chan *c, dma_addr_t dma_dest,
dma_addr_t dma_src, size_t len, unsigned long flags)
{
struct idxd_wq *wq = to_idxd_wq(c);
u32 desc_flags;
struct idxd_device *idxd = wq->idxd;
struct idxd_desc *desc;
if (wq->state != IDXD_WQ_ENABLED)
return NULL;
if (len > idxd->max_xfer_bytes)
return NULL;
op_flag_setup(flags, &desc_flags);
desc = idxd_alloc_desc(wq, IDXD_OP_BLOCK);
if (IS_ERR(desc))
return NULL;
idxd_prep_desc_common(wq, desc->hw, DSA_OPCODE_MEMMOVE,
dma_src, dma_dest, len, desc->compl_dma,
desc_flags);
desc->txd.flags = flags;
return &desc->txd;
}
static int idxd_dma_alloc_chan_resources(struct dma_chan *chan)
{
struct idxd_wq *wq = to_idxd_wq(chan);
struct device *dev = &wq->idxd->pdev->dev;
idxd_wq_get(wq);
dev_dbg(dev, "%s: client_count: %d\n", __func__,
idxd_wq_refcount(wq));
return 0;
}
static void idxd_dma_free_chan_resources(struct dma_chan *chan)
{
struct idxd_wq *wq = to_idxd_wq(chan);
struct device *dev = &wq->idxd->pdev->dev;
idxd_wq_put(wq);
dev_dbg(dev, "%s: client_count: %d\n", __func__,
idxd_wq_refcount(wq));
}
static enum dma_status idxd_dma_tx_status(struct dma_chan *dma_chan,
dma_cookie_t cookie,
struct dma_tx_state *txstate)
{
return DMA_OUT_OF_ORDER;
}
/*
* issue_pending() does not need to do anything since tx_submit() does the job
* already.
*/
static void idxd_dma_issue_pending(struct dma_chan *dma_chan)
{
}
static dma_cookie_t idxd_dma_tx_submit(struct dma_async_tx_descriptor *tx)
{
struct dma_chan *c = tx->chan;
struct idxd_wq *wq = to_idxd_wq(c);
dma_cookie_t cookie;
int rc;
struct idxd_desc *desc = container_of(tx, struct idxd_desc, txd);
cookie = dma_cookie_assign(tx);
rc = idxd_submit_desc(wq, desc);
if (rc < 0) {
idxd_free_desc(wq, desc);
return rc;
}
return cookie;
}
static void idxd_dma_release(struct dma_device *device)
{
struct idxd_dma_dev *idxd_dma = container_of(device, struct idxd_dma_dev, dma);
kfree(idxd_dma);
}
int idxd_register_dma_device(struct idxd_device *idxd)
{
struct idxd_dma_dev *idxd_dma;
struct dma_device *dma;
struct device *dev = &idxd->pdev->dev;
int rc;
idxd_dma = kzalloc_node(sizeof(*idxd_dma), GFP_KERNEL, dev_to_node(dev));
if (!idxd_dma)
return -ENOMEM;
dma = &idxd_dma->dma;
INIT_LIST_HEAD(&dma->channels);
dma->dev = dev;
dma_cap_set(DMA_PRIVATE, dma->cap_mask);
dma_cap_set(DMA_COMPLETION_NO_ORDER, dma->cap_mask);
dma->device_release = idxd_dma_release;
if (idxd->hw.opcap.bits[0] & IDXD_OPCAP_MEMMOVE) {
dma_cap_set(DMA_MEMCPY, dma->cap_mask);
dma->device_prep_dma_memcpy = idxd_dma_submit_memcpy;
}
dma->device_tx_status = idxd_dma_tx_status;
dma->device_issue_pending = idxd_dma_issue_pending;
dma->device_alloc_chan_resources = idxd_dma_alloc_chan_resources;
dma->device_free_chan_resources = idxd_dma_free_chan_resources;
rc = dma_async_device_register(dma);
if (rc < 0) {
kfree(idxd_dma);
return rc;
}
idxd_dma->idxd = idxd;
/*
* This pointer is protected by the refs taken by the dma_chan. It will remain valid
* as long as there are outstanding channels.
*/
idxd->idxd_dma = idxd_dma;
return 0;
}
void idxd_unregister_dma_device(struct idxd_device *idxd)
{
dma_async_device_unregister(&idxd->idxd_dma->dma);
}
int idxd_register_dma_channel(struct idxd_wq *wq)
{
struct idxd_device *idxd = wq->idxd;
struct dma_device *dma = &idxd->idxd_dma->dma;
struct device *dev = &idxd->pdev->dev;
struct idxd_dma_chan *idxd_chan;
struct dma_chan *chan;
int rc, i;
idxd_chan = kzalloc_node(sizeof(*idxd_chan), GFP_KERNEL, dev_to_node(dev));
if (!idxd_chan)
return -ENOMEM;
chan = &idxd_chan->chan;
chan->device = dma;
list_add_tail(&chan->device_node, &dma->channels);
for (i = 0; i < wq->num_descs; i++) {
struct idxd_desc *desc = wq->descs[i];
dma_async_tx_descriptor_init(&desc->txd, chan);
desc->txd.tx_submit = idxd_dma_tx_submit;
}
rc = dma_async_device_channel_register(dma, chan);
if (rc < 0) {
kfree(idxd_chan);
return rc;
}
wq->idxd_chan = idxd_chan;
idxd_chan->wq = wq;
get_device(wq_confdev(wq));
return 0;
}
void idxd_unregister_dma_channel(struct idxd_wq *wq)
{
struct idxd_dma_chan *idxd_chan = wq->idxd_chan;
struct dma_chan *chan = &idxd_chan->chan;
struct idxd_dma_dev *idxd_dma = wq->idxd->idxd_dma;
dma_async_device_channel_unregister(&idxd_dma->dma, chan);
list_del(&chan->device_node);
kfree(wq->idxd_chan);
wq->idxd_chan = NULL;
put_device(wq_confdev(wq));
}
static int idxd_dmaengine_drv_probe(struct idxd_dev *idxd_dev)
{
struct device *dev = &idxd_dev->conf_dev;
struct idxd_wq *wq = idxd_dev_to_wq(idxd_dev);
struct idxd_device *idxd = wq->idxd;
int rc;
if (idxd->state != IDXD_DEV_ENABLED)
return -ENXIO;
mutex_lock(&wq->wq_lock);
wq->type = IDXD_WQT_KERNEL;
rc = idxd_wq_request_irq(wq);
if (rc < 0) {
idxd->cmd_status = IDXD_SCMD_WQ_IRQ_ERR;
dev_dbg(dev, "WQ %d irq setup failed: %d\n", wq->id, rc);
goto err_irq;
}
rc = __drv_enable_wq(wq);
if (rc < 0) {
dev_dbg(dev, "Enable wq %d failed: %d\n", wq->id, rc);
rc = -ENXIO;
goto err;
}
rc = idxd_wq_alloc_resources(wq);
if (rc < 0) {
idxd->cmd_status = IDXD_SCMD_WQ_RES_ALLOC_ERR;
dev_dbg(dev, "WQ resource alloc failed\n");
goto err_res_alloc;
}
rc = idxd_wq_init_percpu_ref(wq);
if (rc < 0) {
idxd->cmd_status = IDXD_SCMD_PERCPU_ERR;
dev_dbg(dev, "percpu_ref setup failed\n");
goto err_ref;
}
rc = idxd_register_dma_channel(wq);
if (rc < 0) {
idxd->cmd_status = IDXD_SCMD_DMA_CHAN_ERR;
dev_dbg(dev, "Failed to register dma channel\n");
goto err_dma;
}
idxd->cmd_status = 0;
mutex_unlock(&wq->wq_lock);
return 0;
err_dma:
__idxd_wq_quiesce(wq);
percpu_ref_exit(&wq->wq_active);
err_ref:
idxd_wq_free_resources(wq);
err_res_alloc:
__drv_disable_wq(wq);
err:
idxd_wq_free_irq(wq);
err_irq:
wq->type = IDXD_WQT_NONE;
mutex_unlock(&wq->wq_lock);
return rc;
}
static void idxd_dmaengine_drv_remove(struct idxd_dev *idxd_dev)
{
struct idxd_wq *wq = idxd_dev_to_wq(idxd_dev);
mutex_lock(&wq->wq_lock);
__idxd_wq_quiesce(wq);
idxd_unregister_dma_channel(wq);
idxd_wq_free_resources(wq);
__drv_disable_wq(wq);
percpu_ref_exit(&wq->wq_active);
idxd_wq_free_irq(wq);
wq->type = IDXD_WQT_NONE;
mutex_unlock(&wq->wq_lock);
}
static enum idxd_dev_type dev_types[] = {
IDXD_DEV_WQ,
IDXD_DEV_NONE,
};
struct idxd_device_driver idxd_dmaengine_drv = {
.probe = idxd_dmaengine_drv_probe,
.remove = idxd_dmaengine_drv_remove,
.name = "dmaengine",
.type = dev_types,
};
EXPORT_SYMBOL_GPL(idxd_dmaengine_drv);