linux/drivers/misc/mic/host/mic_intr.c

631 lines
16 KiB
C

/*
* Intel MIC Platform Software Stack (MPSS)
*
* Copyright(c) 2013 Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2, as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* The full GNU General Public License is included in this distribution in
* the file called "COPYING".
*
* Intel MIC Host driver.
*
*/
#include <linux/pci.h>
#include <linux/interrupt.h>
#include "../common/mic_dev.h"
#include "mic_device.h"
/*
* mic_invoke_callback - Invoke callback functions registered for
* the corresponding source id.
*
* @mdev: pointer to the mic_device instance
* @idx: The interrupt source id.
*
* Returns none.
*/
static inline void mic_invoke_callback(struct mic_device *mdev, int idx)
{
struct mic_intr_cb *intr_cb;
struct pci_dev *pdev = container_of(mdev->sdev->parent,
struct pci_dev, dev);
spin_lock(&mdev->irq_info.mic_intr_lock);
list_for_each_entry(intr_cb, &mdev->irq_info.cb_list[idx], list)
if (intr_cb->func)
intr_cb->func(pdev->irq, intr_cb->data);
spin_unlock(&mdev->irq_info.mic_intr_lock);
}
/**
* mic_interrupt - Generic interrupt handler for
* MSI and INTx based interrupts.
*/
static irqreturn_t mic_interrupt(int irq, void *dev)
{
struct mic_device *mdev = dev;
struct mic_intr_info *info = mdev->intr_info;
u32 mask;
int i;
mask = mdev->ops->ack_interrupt(mdev);
if (!mask)
return IRQ_NONE;
for (i = info->intr_start_idx[MIC_INTR_DB];
i < info->intr_len[MIC_INTR_DB]; i++)
if (mask & BIT(i))
mic_invoke_callback(mdev, i);
return IRQ_HANDLED;
}
/* Return the interrupt offset from the index. Index is 0 based. */
static u16 mic_map_src_to_offset(struct mic_device *mdev,
int intr_src, enum mic_intr_type type)
{
if (type >= MIC_NUM_INTR_TYPES)
return MIC_NUM_OFFSETS;
if (intr_src >= mdev->intr_info->intr_len[type])
return MIC_NUM_OFFSETS;
return mdev->intr_info->intr_start_idx[type] + intr_src;
}
/* Return next available msix_entry. */
static struct msix_entry *mic_get_available_vector(struct mic_device *mdev)
{
int i;
struct mic_irq_info *info = &mdev->irq_info;
for (i = 0; i < info->num_vectors; i++)
if (!info->mic_msi_map[i])
return &info->msix_entries[i];
return NULL;
}
/**
* mic_register_intr_callback - Register a callback handler for the
* given source id.
*
* @mdev: pointer to the mic_device instance
* @idx: The source id to be registered.
* @func: The function to be called when the source id receives
* the interrupt.
* @data: Private data of the requester.
* Return the callback structure that was registered or an
* appropriate error on failure.
*/
static struct mic_intr_cb *mic_register_intr_callback(struct mic_device *mdev,
u8 idx, irqreturn_t (*func) (int irq, void *dev),
void *data)
{
struct mic_intr_cb *intr_cb;
unsigned long flags;
int rc;
intr_cb = kmalloc(sizeof(*intr_cb), GFP_KERNEL);
if (!intr_cb)
return ERR_PTR(-ENOMEM);
intr_cb->func = func;
intr_cb->data = data;
intr_cb->cb_id = ida_simple_get(&mdev->irq_info.cb_ida,
0, 0, GFP_KERNEL);
if (intr_cb->cb_id < 0) {
rc = intr_cb->cb_id;
goto ida_fail;
}
spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
list_add_tail(&intr_cb->list, &mdev->irq_info.cb_list[idx]);
spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
return intr_cb;
ida_fail:
kfree(intr_cb);
return ERR_PTR(rc);
}
/**
* mic_unregister_intr_callback - Unregister the callback handler
* identified by its callback id.
*
* @mdev: pointer to the mic_device instance
* @idx: The callback structure id to be unregistered.
* Return the source id that was unregistered or MIC_NUM_OFFSETS if no
* such callback handler was found.
*/
static u8 mic_unregister_intr_callback(struct mic_device *mdev, u32 idx)
{
struct list_head *pos, *tmp;
struct mic_intr_cb *intr_cb;
unsigned long flags;
int i;
for (i = 0; i < MIC_NUM_OFFSETS; i++) {
spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
list_for_each_safe(pos, tmp, &mdev->irq_info.cb_list[i]) {
intr_cb = list_entry(pos, struct mic_intr_cb, list);
if (intr_cb->cb_id == idx) {
list_del(pos);
ida_simple_remove(&mdev->irq_info.cb_ida,
intr_cb->cb_id);
kfree(intr_cb);
spin_unlock_irqrestore(
&mdev->irq_info.mic_intr_lock, flags);
return i;
}
}
spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
}
return MIC_NUM_OFFSETS;
}
/**
* mic_setup_msix - Initializes MSIx interrupts.
*
* @mdev: pointer to mic_device instance
*
*
* RETURNS: An appropriate -ERRNO error value on error, or zero for success.
*/
static int mic_setup_msix(struct mic_device *mdev, struct pci_dev *pdev)
{
int rc, i;
int entry_size = sizeof(*mdev->irq_info.msix_entries);
mdev->irq_info.msix_entries = kmalloc_array(MIC_MIN_MSIX,
entry_size, GFP_KERNEL);
if (!mdev->irq_info.msix_entries) {
rc = -ENOMEM;
goto err_nomem1;
}
for (i = 0; i < MIC_MIN_MSIX; i++)
mdev->irq_info.msix_entries[i].entry = i;
rc = pci_enable_msix(pdev, mdev->irq_info.msix_entries,
MIC_MIN_MSIX);
if (rc) {
dev_dbg(&pdev->dev, "Error enabling MSIx. rc = %d\n", rc);
goto err_enable_msix;
}
mdev->irq_info.num_vectors = MIC_MIN_MSIX;
mdev->irq_info.mic_msi_map = kzalloc((sizeof(u32) *
mdev->irq_info.num_vectors), GFP_KERNEL);
if (!mdev->irq_info.mic_msi_map) {
rc = -ENOMEM;
goto err_nomem2;
}
dev_dbg(mdev->sdev->parent,
"%d MSIx irqs setup\n", mdev->irq_info.num_vectors);
return 0;
err_nomem2:
pci_disable_msix(pdev);
err_enable_msix:
kfree(mdev->irq_info.msix_entries);
err_nomem1:
mdev->irq_info.num_vectors = 0;
return rc;
}
/**
* mic_setup_callbacks - Initialize data structures needed
* to handle callbacks.
*
* @mdev: pointer to mic_device instance
*/
static int mic_setup_callbacks(struct mic_device *mdev)
{
int i;
mdev->irq_info.cb_list = kmalloc_array(MIC_NUM_OFFSETS,
sizeof(*mdev->irq_info.cb_list),
GFP_KERNEL);
if (!mdev->irq_info.cb_list)
return -ENOMEM;
for (i = 0; i < MIC_NUM_OFFSETS; i++)
INIT_LIST_HEAD(&mdev->irq_info.cb_list[i]);
ida_init(&mdev->irq_info.cb_ida);
spin_lock_init(&mdev->irq_info.mic_intr_lock);
return 0;
}
/**
* mic_release_callbacks - Uninitialize data structures needed
* to handle callbacks.
*
* @mdev: pointer to mic_device instance
*/
static void mic_release_callbacks(struct mic_device *mdev)
{
unsigned long flags;
struct list_head *pos, *tmp;
struct mic_intr_cb *intr_cb;
int i;
for (i = 0; i < MIC_NUM_OFFSETS; i++) {
spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
if (list_empty(&mdev->irq_info.cb_list[i])) {
spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock,
flags);
break;
}
list_for_each_safe(pos, tmp, &mdev->irq_info.cb_list[i]) {
intr_cb = list_entry(pos, struct mic_intr_cb, list);
list_del(pos);
ida_simple_remove(&mdev->irq_info.cb_ida,
intr_cb->cb_id);
kfree(intr_cb);
}
spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
}
ida_destroy(&mdev->irq_info.cb_ida);
kfree(mdev->irq_info.cb_list);
}
/**
* mic_setup_msi - Initializes MSI interrupts.
*
* @mdev: pointer to mic_device instance
* @pdev: PCI device structure
*
* RETURNS: An appropriate -ERRNO error value on error, or zero for success.
*/
static int mic_setup_msi(struct mic_device *mdev, struct pci_dev *pdev)
{
int rc;
rc = pci_enable_msi(pdev);
if (rc) {
dev_dbg(&pdev->dev, "Error enabling MSI. rc = %d\n", rc);
return rc;
}
mdev->irq_info.num_vectors = 1;
mdev->irq_info.mic_msi_map = kzalloc((sizeof(u32) *
mdev->irq_info.num_vectors), GFP_KERNEL);
if (!mdev->irq_info.mic_msi_map) {
rc = -ENOMEM;
goto err_nomem1;
}
rc = mic_setup_callbacks(mdev);
if (rc) {
dev_err(&pdev->dev, "Error setting up callbacks\n");
goto err_nomem2;
}
rc = request_irq(pdev->irq, mic_interrupt, 0 , "mic-msi", mdev);
if (rc) {
dev_err(&pdev->dev, "Error allocating MSI interrupt\n");
goto err_irq_req_fail;
}
dev_dbg(&pdev->dev, "%d MSI irqs setup\n", mdev->irq_info.num_vectors);
return 0;
err_irq_req_fail:
mic_release_callbacks(mdev);
err_nomem2:
kfree(mdev->irq_info.mic_msi_map);
err_nomem1:
pci_disable_msi(pdev);
mdev->irq_info.num_vectors = 0;
return rc;
}
/**
* mic_setup_intx - Initializes legacy interrupts.
*
* @mdev: pointer to mic_device instance
* @pdev: PCI device structure
*
* RETURNS: An appropriate -ERRNO error value on error, or zero for success.
*/
static int mic_setup_intx(struct mic_device *mdev, struct pci_dev *pdev)
{
int rc;
pci_msi_off(pdev);
/* Enable intx */
pci_intx(pdev, 1);
rc = mic_setup_callbacks(mdev);
if (rc) {
dev_err(&pdev->dev, "Error setting up callbacks\n");
goto err_nomem;
}
rc = request_irq(pdev->irq, mic_interrupt,
IRQF_SHARED, "mic-intx", mdev);
if (rc)
goto err;
dev_dbg(&pdev->dev, "intx irq setup\n");
return 0;
err:
mic_release_callbacks(mdev);
err_nomem:
return rc;
}
/**
* mic_next_db - Retrieve the next doorbell interrupt source id.
* The id is picked sequentially from the available pool of
* doorlbell ids.
*
* @mdev: pointer to the mic_device instance.
*
* Returns the next doorbell interrupt source.
*/
int mic_next_db(struct mic_device *mdev)
{
int next_db;
next_db = mdev->irq_info.next_avail_src %
mdev->intr_info->intr_len[MIC_INTR_DB];
mdev->irq_info.next_avail_src++;
return next_db;
}
#define COOKIE_ID_SHIFT 16
#define GET_ENTRY(cookie) ((cookie) & 0xFFFF)
#define GET_OFFSET(cookie) ((cookie) >> COOKIE_ID_SHIFT)
#define MK_COOKIE(x, y) ((x) | (y) << COOKIE_ID_SHIFT)
/**
* mic_request_irq - request an irq. mic_mutex needs
* to be held before calling this function.
*
* @mdev: pointer to mic_device instance
* @func: The callback function that handles the interrupt.
* The function needs to call ack_interrupts
* (mdev->ops->ack_interrupt(mdev)) when handling the interrupts.
* @name: The ASCII name of the callee requesting the irq.
* @data: private data that is returned back when calling the
* function handler.
* @intr_src: The source id of the requester. Its the doorbell id
* for Doorbell interrupts and DMA channel id for DMA interrupts.
* @type: The type of interrupt. Values defined in mic_intr_type
*
* returns: The cookie that is transparent to the caller. Passed
* back when calling mic_free_irq. An appropriate error code
* is returned on failure. Caller needs to use IS_ERR(return_val)
* to check for failure and PTR_ERR(return_val) to obtained the
* error code.
*
*/
struct mic_irq *mic_request_irq(struct mic_device *mdev,
irqreturn_t (*func)(int irq, void *dev),
const char *name, void *data, int intr_src,
enum mic_intr_type type)
{
u16 offset;
int rc = 0;
struct msix_entry *msix = NULL;
unsigned long cookie = 0;
u16 entry;
struct mic_intr_cb *intr_cb;
struct pci_dev *pdev = container_of(mdev->sdev->parent,
struct pci_dev, dev);
offset = mic_map_src_to_offset(mdev, intr_src, type);
if (offset >= MIC_NUM_OFFSETS) {
dev_err(mdev->sdev->parent,
"Error mapping index %d to a valid source id.\n",
intr_src);
rc = -EINVAL;
goto err;
}
if (mdev->irq_info.num_vectors > 1) {
msix = mic_get_available_vector(mdev);
if (!msix) {
dev_err(mdev->sdev->parent,
"No MSIx vectors available for use.\n");
rc = -ENOSPC;
goto err;
}
rc = request_irq(msix->vector, func, 0, name, data);
if (rc) {
dev_dbg(mdev->sdev->parent,
"request irq failed rc = %d\n", rc);
goto err;
}
entry = msix->entry;
mdev->irq_info.mic_msi_map[entry] |= BIT(offset);
mdev->intr_ops->program_msi_to_src_map(mdev,
entry, offset, true);
cookie = MK_COOKIE(entry, offset);
dev_dbg(mdev->sdev->parent, "irq: %d assigned for src: %d\n",
msix->vector, intr_src);
} else {
intr_cb = mic_register_intr_callback(mdev,
offset, func, data);
if (IS_ERR(intr_cb)) {
dev_err(mdev->sdev->parent,
"No available callback entries for use\n");
rc = PTR_ERR(intr_cb);
goto err;
}
entry = 0;
if (pci_dev_msi_enabled(pdev)) {
mdev->irq_info.mic_msi_map[entry] |= (1 << offset);
mdev->intr_ops->program_msi_to_src_map(mdev,
entry, offset, true);
}
cookie = MK_COOKIE(entry, intr_cb->cb_id);
dev_dbg(mdev->sdev->parent, "callback %d registered for src: %d\n",
intr_cb->cb_id, intr_src);
}
return (struct mic_irq *)cookie;
err:
return ERR_PTR(rc);
}
/**
* mic_free_irq - free irq. mic_mutex
* needs to be held before calling this function.
*
* @mdev: pointer to mic_device instance
* @cookie: cookie obtained during a successful call to mic_request_irq
* @data: private data specified by the calling function during the
* mic_request_irq
*
* returns: none.
*/
void mic_free_irq(struct mic_device *mdev,
struct mic_irq *cookie, void *data)
{
u32 offset;
u32 entry;
u8 src_id;
unsigned int irq;
struct pci_dev *pdev = container_of(mdev->sdev->parent,
struct pci_dev, dev);
entry = GET_ENTRY((unsigned long)cookie);
offset = GET_OFFSET((unsigned long)cookie);
if (mdev->irq_info.num_vectors > 1) {
if (entry >= mdev->irq_info.num_vectors) {
dev_warn(mdev->sdev->parent,
"entry %d should be < num_irq %d\n",
entry, mdev->irq_info.num_vectors);
return;
}
irq = mdev->irq_info.msix_entries[entry].vector;
free_irq(irq, data);
mdev->irq_info.mic_msi_map[entry] &= ~(BIT(offset));
mdev->intr_ops->program_msi_to_src_map(mdev,
entry, offset, false);
dev_dbg(mdev->sdev->parent, "irq: %d freed\n", irq);
} else {
irq = pdev->irq;
src_id = mic_unregister_intr_callback(mdev, offset);
if (src_id >= MIC_NUM_OFFSETS) {
dev_warn(mdev->sdev->parent, "Error unregistering callback\n");
return;
}
if (pci_dev_msi_enabled(pdev)) {
mdev->irq_info.mic_msi_map[entry] &= ~(BIT(src_id));
mdev->intr_ops->program_msi_to_src_map(mdev,
entry, src_id, false);
}
dev_dbg(mdev->sdev->parent, "callback %d unregistered for src: %d\n",
offset, src_id);
}
}
/**
* mic_setup_interrupts - Initializes interrupts.
*
* @mdev: pointer to mic_device instance
* @pdev: PCI device structure
*
* RETURNS: An appropriate -ERRNO error value on error, or zero for success.
*/
int mic_setup_interrupts(struct mic_device *mdev, struct pci_dev *pdev)
{
int rc;
rc = mic_setup_msix(mdev, pdev);
if (!rc)
goto done;
rc = mic_setup_msi(mdev, pdev);
if (!rc)
goto done;
rc = mic_setup_intx(mdev, pdev);
if (rc) {
dev_err(mdev->sdev->parent, "no usable interrupts\n");
return rc;
}
done:
mdev->intr_ops->enable_interrupts(mdev);
return 0;
}
/**
* mic_free_interrupts - Frees interrupts setup by mic_setup_interrupts
*
* @mdev: pointer to mic_device instance
* @pdev: PCI device structure
*
* returns none.
*/
void mic_free_interrupts(struct mic_device *mdev, struct pci_dev *pdev)
{
int i;
mdev->intr_ops->disable_interrupts(mdev);
if (mdev->irq_info.num_vectors > 1) {
for (i = 0; i < mdev->irq_info.num_vectors; i++) {
if (mdev->irq_info.mic_msi_map[i])
dev_warn(&pdev->dev, "irq %d may still be in use.\n",
mdev->irq_info.msix_entries[i].vector);
}
kfree(mdev->irq_info.mic_msi_map);
kfree(mdev->irq_info.msix_entries);
pci_disable_msix(pdev);
} else {
if (pci_dev_msi_enabled(pdev)) {
free_irq(pdev->irq, mdev);
kfree(mdev->irq_info.mic_msi_map);
pci_disable_msi(pdev);
} else {
free_irq(pdev->irq, mdev);
}
mic_release_callbacks(mdev);
}
}
/**
* mic_intr_restore - Restore MIC interrupt registers.
*
* @mdev: pointer to mic_device instance.
*
* Restore the interrupt registers to values previously
* stored in the SW data structures. mic_mutex needs to
* be held before calling this function.
*
* returns None.
*/
void mic_intr_restore(struct mic_device *mdev)
{
int entry, offset;
struct pci_dev *pdev = container_of(mdev->sdev->parent,
struct pci_dev, dev);
if (!pci_dev_msi_enabled(pdev))
return;
for (entry = 0; entry < mdev->irq_info.num_vectors; entry++) {
for (offset = 0; offset < MIC_NUM_OFFSETS; offset++) {
if (mdev->irq_info.mic_msi_map[entry] & BIT(offset))
mdev->intr_ops->program_msi_to_src_map(mdev,
entry, offset, true);
}
}
}