From 3e037454bcfa4b187e8293d2121bd8c0f5a5c31c Mon Sep 17 00:00:00 2001 From: Shannon Nelson Date: Tue, 16 Oct 2007 01:27:40 -0700 Subject: 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 Acked-by: David S. Miller [bunk@kernel.org: drivers/dma/ioat_dma.c: make 3 functions static] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/dma/ioat_dma.c | 346 ++++++++++++++++++++++++++++++++-------- drivers/dma/ioatdma.h | 12 ++ drivers/dma/ioatdma_registers.h | 6 +- include/linux/bitops.h | 6 + 4 files changed, 304 insertions(+), 66 deletions(-) diff --git a/drivers/dma/ioat_dma.c b/drivers/dma/ioat_dma.c index eef83ea291a..66c5bb53211 100644 --- a/drivers/dma/ioat_dma.c +++ b/drivers/dma/ioat_dma.c @@ -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; - - writeb(IOAT_INTRCTRL_MASTER_INT_EN, - device->reg_base + IOAT_INTRCTRL_OFFSET); - pci_set_master(pdev); + goto err_setup_interrupts; - 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); diff --git a/drivers/dma/ioatdma.h b/drivers/dma/ioatdma.h index 0b8ffbde1e6..2abf0b88a97 100644 --- a/drivers/dma/ioatdma.h +++ b/drivers/dma/ioatdma.h @@ -28,6 +28,14 @@ #include #include +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 */ diff --git a/drivers/dma/ioatdma_registers.h b/drivers/dma/ioatdma_registers.h index a30c7349075..baaab5ea146 100644 --- a/drivers/dma/ioatdma_registers.h +++ b/drivers/dma/ioatdma_registers.h @@ -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 */ diff --git a/include/linux/bitops.h b/include/linux/bitops.h index 638165f571d..b9fb8ee3308 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -8,6 +8,12 @@ */ #include +#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; -- cgit v1.2.3