I/OAT: Add support for MSI and MSI-X

Add support for MSI and MSI-X interrupt handling, including the ability
to choose the desired interrupt method.

Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Acked-by: David S. Miller <davem@davemloft.net>
[bunk@kernel.org: drivers/dma/ioat_dma.c: make 3 functions static]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Shannon Nelson 2007-10-16 01:27:40 -07:00 committed by Linus Torvalds
parent 8ab89567da
commit 3e037454bc
4 changed files with 304 additions and 66 deletions

View file

@ -47,6 +47,65 @@
static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan);
static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan);
static struct ioat_dma_chan *ioat_lookup_chan_by_index(struct ioatdma_device *device,
int index)
{
return device->idx[index];
}
/**
* ioat_dma_do_interrupt - handler used for single vector interrupt mode
* @irq: interrupt id
* @data: interrupt data
*/
static irqreturn_t ioat_dma_do_interrupt(int irq, void *data)
{
struct ioatdma_device *instance = data;
struct ioat_dma_chan *ioat_chan;
unsigned long attnstatus;
int bit;
u8 intrctrl;
intrctrl = readb(instance->reg_base + IOAT_INTRCTRL_OFFSET);
if (!(intrctrl & IOAT_INTRCTRL_MASTER_INT_EN))
return IRQ_NONE;
if (!(intrctrl & IOAT_INTRCTRL_INT_STATUS)) {
writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
return IRQ_NONE;
}
attnstatus = readl(instance->reg_base + IOAT_ATTNSTATUS_OFFSET);
for_each_bit(bit, &attnstatus, BITS_PER_LONG) {
ioat_chan = ioat_lookup_chan_by_index(instance, bit);
tasklet_schedule(&ioat_chan->cleanup_task);
}
writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
return IRQ_HANDLED;
}
/**
* ioat_dma_do_interrupt_msix - handler used for vector-per-channel interrupt mode
* @irq: interrupt id
* @data: interrupt data
*/
static irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data)
{
struct ioat_dma_chan *ioat_chan = data;
tasklet_schedule(&ioat_chan->cleanup_task);
return IRQ_HANDLED;
}
static void ioat_dma_cleanup_tasklet(unsigned long data);
/**
* ioat_dma_enumerate_channels - find and initialize the device's channels
* @device: the device to be enumerated
*/
static int ioat_dma_enumerate_channels(struct ioatdma_device *device)
{
u8 xfercap_scale;
@ -76,6 +135,11 @@ static int ioat_dma_enumerate_channels(struct ioatdma_device *device)
ioat_chan->common.device = &device->common;
list_add_tail(&ioat_chan->common.device_node,
&device->common.channels);
device->idx[i] = ioat_chan;
tasklet_init(&ioat_chan->cleanup_task,
ioat_dma_cleanup_tasklet,
(unsigned long) ioat_chan);
tasklet_disable(&ioat_chan->cleanup_task);
}
return device->common.chancnt;
}
@ -234,6 +298,7 @@ static int ioat_dma_alloc_chan_resources(struct dma_chan *chan)
writel(((u64) ioat_chan->completion_addr) >> 32,
ioat_chan->reg_base + IOAT_CHANCMP_OFFSET_HIGH);
tasklet_enable(&ioat_chan->cleanup_task);
ioat_dma_start_null_desc(ioat_chan);
return i;
}
@ -245,9 +310,14 @@ static void ioat_dma_free_chan_resources(struct dma_chan *chan)
struct ioat_desc_sw *desc, *_desc;
int in_use_descs = 0;
tasklet_disable(&ioat_chan->cleanup_task);
ioat_dma_memcpy_cleanup(ioat_chan);
/* Delay 100ms after reset to allow internal DMA logic to quiesce
* before removing DMA descriptor resources.
*/
writeb(IOAT_CHANCMD_RESET, ioat_chan->reg_base + IOAT_CHANCMD_OFFSET);
mdelay(100);
spin_lock_bh(&ioat_chan->desc_lock);
list_for_each_entry_safe(desc, _desc, &ioat_chan->used_desc, node) {
@ -276,6 +346,34 @@ static void ioat_dma_free_chan_resources(struct dma_chan *chan)
in_use_descs - 1);
ioat_chan->last_completion = ioat_chan->completion_addr = 0;
ioat_chan->pending = 0;
}
/**
* ioat_dma_get_next_descriptor - return the next available descriptor
* @ioat_chan: IOAT DMA channel handle
*
* Gets the next descriptor from the chain, and must be called with the
* channel's desc_lock held. Allocates more descriptors if the channel
* has run out.
*/
static struct ioat_desc_sw *ioat_dma_get_next_descriptor(
struct ioat_dma_chan *ioat_chan)
{
struct ioat_desc_sw *new = NULL;
if (!list_empty(&ioat_chan->free_desc)) {
new = to_ioat_desc(ioat_chan->free_desc.next);
list_del(&new->node);
} else {
/* try to get another desc */
new = ioat_dma_alloc_descriptor(ioat_chan, GFP_ATOMIC);
/* will this ever happen? */
/* TODO add upper limit on these */
BUG_ON(!new);
}
prefetch(new->hw);
return new;
}
static struct dma_async_tx_descriptor *ioat_dma_prep_memcpy(
@ -300,17 +398,7 @@ static struct dma_async_tx_descriptor *ioat_dma_prep_memcpy(
spin_lock_bh(&ioat_chan->desc_lock);
while (len) {
if (!list_empty(&ioat_chan->free_desc)) {
new = to_ioat_desc(ioat_chan->free_desc.next);
list_del(&new->node);
} else {
/* try to get another desc */
new = ioat_dma_alloc_descriptor(ioat_chan, GFP_ATOMIC);
/* will this ever happen? */
/* TODO add upper limit on these */
BUG_ON(!new);
}
new = ioat_dma_get_next_descriptor(ioat_chan);
copy = min((u32) len, ioat_chan->xfercap);
new->hw->size = copy;
@ -360,6 +448,14 @@ static void ioat_dma_memcpy_issue_pending(struct dma_chan *chan)
}
}
static void ioat_dma_cleanup_tasklet(unsigned long data)
{
struct ioat_dma_chan *chan = (void *)data;
ioat_dma_memcpy_cleanup(chan);
writew(IOAT_CHANCTRL_INT_DISABLE,
chan->reg_base + IOAT_CHANCTRL_OFFSET);
}
static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan)
{
unsigned long phys_complete;
@ -397,6 +493,7 @@ static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan)
return;
}
cookie = 0;
spin_lock_bh(&ioat_chan->desc_lock);
list_for_each_entry_safe(desc, _desc, &ioat_chan->used_desc, node) {
@ -509,48 +606,13 @@ static enum dma_status ioat_dma_is_complete(struct dma_chan *chan,
/* PCI API */
static irqreturn_t ioat_do_interrupt(int irq, void *data)
{
struct ioatdma_device *instance = data;
unsigned long attnstatus;
u8 intrctrl;
intrctrl = readb(instance->reg_base + IOAT_INTRCTRL_OFFSET);
if (!(intrctrl & IOAT_INTRCTRL_MASTER_INT_EN))
return IRQ_NONE;
if (!(intrctrl & IOAT_INTRCTRL_INT_STATUS)) {
writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
return IRQ_NONE;
}
attnstatus = readl(instance->reg_base + IOAT_ATTNSTATUS_OFFSET);
printk(KERN_ERR "ioatdma: interrupt! status %lx\n", attnstatus);
writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
return IRQ_HANDLED;
}
static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan)
{
struct ioat_desc_sw *desc;
spin_lock_bh(&ioat_chan->desc_lock);
if (!list_empty(&ioat_chan->free_desc)) {
desc = to_ioat_desc(ioat_chan->free_desc.next);
list_del(&desc->node);
} else {
/* try to get another desc */
spin_unlock_bh(&ioat_chan->desc_lock);
desc = ioat_dma_alloc_descriptor(ioat_chan, GFP_KERNEL);
spin_lock_bh(&ioat_chan->desc_lock);
/* will this ever happen? */
BUG_ON(!desc);
}
desc = ioat_dma_get_next_descriptor(ioat_chan);
desc->hw->ctl = IOAT_DMA_DESCRIPTOR_NUL;
desc->hw->next = 0;
desc->async_tx.ack = 1;
@ -571,7 +633,11 @@ static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan)
*/
#define IOAT_TEST_SIZE 2000
static int ioat_self_test(struct ioatdma_device *device)
/**
* ioat_dma_self_test - Perform a IOAT transaction to verify the HW works.
* @device: device to be tested
*/
static int ioat_dma_self_test(struct ioatdma_device *device)
{
int i;
u8 *src;
@ -639,6 +705,161 @@ out:
return err;
}
static char ioat_interrupt_style[32] = "msix";
module_param_string(ioat_interrupt_style, ioat_interrupt_style,
sizeof(ioat_interrupt_style), 0644);
MODULE_PARM_DESC(ioat_interrupt_style,
"set ioat interrupt style: msix (default), "
"msix-single-vector, msi, intx)");
/**
* ioat_dma_setup_interrupts - setup interrupt handler
* @device: ioat device
*/
static int ioat_dma_setup_interrupts(struct ioatdma_device *device)
{
struct ioat_dma_chan *ioat_chan;
int err, i, j, msixcnt;
u8 intrctrl = 0;
if (!strcmp(ioat_interrupt_style, "msix"))
goto msix;
if (!strcmp(ioat_interrupt_style, "msix-single-vector"))
goto msix_single_vector;
if (!strcmp(ioat_interrupt_style, "msi"))
goto msi;
if (!strcmp(ioat_interrupt_style, "intx"))
goto intx;
msix:
/* The number of MSI-X vectors should equal the number of channels */
msixcnt = device->common.chancnt;
for (i = 0; i < msixcnt; i++)
device->msix_entries[i].entry = i;
err = pci_enable_msix(device->pdev, device->msix_entries, msixcnt);
if (err < 0)
goto msi;
if (err > 0)
goto msix_single_vector;
for (i = 0; i < msixcnt; i++) {
ioat_chan = ioat_lookup_chan_by_index(device, i);
err = request_irq(device->msix_entries[i].vector,
ioat_dma_do_interrupt_msix,
0, "ioat-msix", ioat_chan);
if (err) {
for (j = 0; j < i; j++) {
ioat_chan =
ioat_lookup_chan_by_index(device, j);
free_irq(device->msix_entries[j].vector,
ioat_chan);
}
goto msix_single_vector;
}
}
intrctrl |= IOAT_INTRCTRL_MSIX_VECTOR_CONTROL;
device->irq_mode = msix_multi_vector;
goto done;
msix_single_vector:
device->msix_entries[0].entry = 0;
err = pci_enable_msix(device->pdev, device->msix_entries, 1);
if (err)
goto msi;
err = request_irq(device->msix_entries[0].vector, ioat_dma_do_interrupt,
0, "ioat-msix", device);
if (err) {
pci_disable_msix(device->pdev);
goto msi;
}
device->irq_mode = msix_single_vector;
goto done;
msi:
err = pci_enable_msi(device->pdev);
if (err)
goto intx;
err = request_irq(device->pdev->irq, ioat_dma_do_interrupt,
0, "ioat-msi", device);
if (err) {
pci_disable_msi(device->pdev);
goto intx;
}
/*
* CB 1.2 devices need a bit set in configuration space to enable MSI
*/
if (device->version == IOAT_VER_1_2) {
u32 dmactrl;
pci_read_config_dword(device->pdev,
IOAT_PCI_DMACTRL_OFFSET, &dmactrl);
dmactrl |= IOAT_PCI_DMACTRL_MSI_EN;
pci_write_config_dword(device->pdev,
IOAT_PCI_DMACTRL_OFFSET, dmactrl);
}
device->irq_mode = msi;
goto done;
intx:
err = request_irq(device->pdev->irq, ioat_dma_do_interrupt,
IRQF_SHARED, "ioat-intx", device);
if (err)
goto err_no_irq;
device->irq_mode = intx;
done:
intrctrl |= IOAT_INTRCTRL_MASTER_INT_EN;
writeb(intrctrl, device->reg_base + IOAT_INTRCTRL_OFFSET);
return 0;
err_no_irq:
/* Disable all interrupt generation */
writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
dev_err(&device->pdev->dev, "no usable interrupts\n");
device->irq_mode = none;
return -1;
}
/**
* ioat_dma_remove_interrupts - remove whatever interrupts were set
* @device: ioat device
*/
static void ioat_dma_remove_interrupts(struct ioatdma_device *device)
{
struct ioat_dma_chan *ioat_chan;
int i;
/* Disable all interrupt generation */
writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
switch (device->irq_mode) {
case msix_multi_vector:
for (i = 0; i < device->common.chancnt; i++) {
ioat_chan = ioat_lookup_chan_by_index(device, i);
free_irq(device->msix_entries[i].vector, ioat_chan);
}
pci_disable_msix(device->pdev);
break;
case msix_single_vector:
free_irq(device->msix_entries[0].vector, device);
pci_disable_msix(device->pdev);
break;
case msi:
free_irq(device->pdev->irq, device);
pci_disable_msi(device->pdev);
break;
case intx:
free_irq(device->pdev->irq, device);
break;
case none:
dev_warn(&device->pdev->dev,
"call to %s without interrupts setup\n", __func__);
}
device->irq_mode = none;
}
struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev,
void __iomem *iobase)
{
@ -684,21 +905,16 @@ struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev,
device->common.device_issue_pending = ioat_dma_memcpy_issue_pending;
device->common.device_dependency_added = ioat_dma_dependency_added;
device->common.dev = &pdev->dev;
printk(KERN_INFO "ioatdma: Intel(R) I/OAT DMA Engine found,"
" %d channels, device version 0x%02x\n",
device->common.chancnt, device->version);
dev_err(&device->pdev->dev,
"ioatdma: Intel(R) I/OAT DMA Engine found,"
" %d channels, device version 0x%02x\n",
device->common.chancnt, device->version);
pci_set_drvdata(pdev, device);
err = request_irq(pdev->irq, &ioat_do_interrupt, IRQF_SHARED, "ioat",
device);
err = ioat_dma_setup_interrupts(device);
if (err)
goto err_irq;
goto err_setup_interrupts;
writeb(IOAT_INTRCTRL_MASTER_INT_EN,
device->reg_base + IOAT_INTRCTRL_OFFSET);
pci_set_master(pdev);
err = ioat_self_test(device);
err = ioat_dma_self_test(device);
if (err)
goto err_self_test;
@ -707,8 +923,8 @@ struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev,
return device;
err_self_test:
free_irq(device->pdev->irq, device);
err_irq:
ioat_dma_remove_interrupts(device);
err_setup_interrupts:
pci_pool_destroy(device->completion_pool);
err_completion_pool:
pci_pool_destroy(device->dma_pool);
@ -716,8 +932,8 @@ err_dma_pool:
kfree(device);
err_kzalloc:
iounmap(iobase);
printk(KERN_ERR
"ioatdma: Intel(R) I/OAT DMA Engine initialization failed\n");
dev_err(&device->pdev->dev,
"ioatdma: Intel(R) I/OAT DMA Engine initialization failed\n");
return NULL;
}
@ -728,7 +944,7 @@ void ioat_dma_remove(struct ioatdma_device *device)
dma_async_device_unregister(&device->common);
free_irq(device->pdev->irq, device);
ioat_dma_remove_interrupts(device);
pci_pool_destroy(device->dma_pool);
pci_pool_destroy(device->completion_pool);

View file

@ -28,6 +28,14 @@
#include <linux/cache.h>
#include <linux/pci_ids.h>
enum ioat_interrupt {
none = 0,
msix_multi_vector = 1,
msix_single_vector = 2,
msi = 3,
intx = 4,
};
#define IOAT_LOW_COMPLETION_MASK 0xffffffc0
/**
@ -46,6 +54,9 @@ struct ioatdma_device {
struct pci_pool *completion_pool;
struct dma_device common;
u8 version;
enum ioat_interrupt irq_mode;
struct msix_entry msix_entries[4];
struct ioat_dma_chan *idx[4];
};
/**
@ -94,6 +105,7 @@ struct ioat_dma_chan {
u32 high;
};
} *completion_virt;
struct tasklet_struct cleanup_task;
};
/* wrapper around hardware descriptor format + additional software fields */

View file

@ -1,5 +1,5 @@
/*
* Copyright(c) 2004 - 2006 Intel Corporation. All rights reserved.
* Copyright(c) 2004 - 2007 Intel Corporation. All rights reserved.
*
* 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
@ -21,6 +21,9 @@
#ifndef _IOAT_REGISTERS_H_
#define _IOAT_REGISTERS_H_
#define IOAT_PCI_DMACTRL_OFFSET 0x48
#define IOAT_PCI_DMACTRL_DMA_EN 0x00000001
#define IOAT_PCI_DMACTRL_MSI_EN 0x00000002
/* MMIO Device Registers */
#define IOAT_CHANCNT_OFFSET 0x00 /* 8-bit */
@ -39,6 +42,7 @@
#define IOAT_INTRCTRL_MASTER_INT_EN 0x01 /* Master Interrupt Enable */
#define IOAT_INTRCTRL_INT_STATUS 0x02 /* ATTNSTATUS -or- Channel Int */
#define IOAT_INTRCTRL_INT 0x04 /* INT_STATUS -and- MASTER_INT_EN */
#define IOAT_INTRCTRL_MSIX_VECTOR_CONTROL 0x08 /* Enable all MSI-X vectors */
#define IOAT_ATTNSTATUS_OFFSET 0x04 /* Each bit is a channel */

View file

@ -8,6 +8,12 @@
*/
#include <asm/bitops.h>
#define for_each_bit(bit, addr, size) \
for ((bit) = find_first_bit((addr), (size)); \
(bit) < (size); \
(bit) = find_next_bit((addr), (size), (bit) + 1))
static __inline__ int get_bitmask_order(unsigned int count)
{
int order;