I/OAT: Split PCI startup from DMA handling code
authorShannon Nelson <shannon.nelson@intel.com>
Tue, 16 Oct 2007 08:27:39 +0000 (01:27 -0700)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Tue, 16 Oct 2007 16:43:09 +0000 (09:43 -0700)
Split the general PCI startup from the DMA handling code in order to
prepare for adding support for DCA services and future versions of the
ioatdma device.

    [Rusty Russell] Removal of __unsafe() usage.

Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/dma/Makefile
drivers/dma/ioat.c [new file with mode: 0644]
drivers/dma/ioat_dma.c
drivers/dma/ioatdma.h
drivers/dma/ioatdma_hw.h

index 77bee99df02a1fc162f8811b63d93e493c7b47d1..cec0c9c5df655a8ef82756d849b019d8c19257c8 100644 (file)
@@ -1,5 +1,5 @@
 obj-$(CONFIG_DMA_ENGINE) += dmaengine.o
 obj-$(CONFIG_NET_DMA) += iovlock.o
 obj-$(CONFIG_INTEL_IOATDMA) += ioatdma.o
-ioatdma-objs := ioat_dma.o
+ioatdma-objs := ioat.o ioat_dma.o
 obj-$(CONFIG_INTEL_IOP_ADMA) += iop-adma.o
diff --git a/drivers/dma/ioat.c b/drivers/dma/ioat.c
new file mode 100644 (file)
index 0000000..ae5817b
--- /dev/null
@@ -0,0 +1,196 @@
+/*
+ * Intel I/OAT DMA Linux driver
+ * Copyright(c) 2004 - 2007 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions 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.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ *
+ */
+
+/*
+ * This driver supports an Intel I/OAT DMA engine, which does asynchronous
+ * copy operations.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include "ioatdma.h"
+#include "ioatdma_registers.h"
+#include "ioatdma_hw.h"
+
+MODULE_VERSION("1.24");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Intel Corporation");
+
+static struct pci_device_id ioat_pci_tbl[] = {
+       { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT) },
+       { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_CNB)  },
+       { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SCNB) },
+       { PCI_DEVICE(PCI_VENDOR_ID_UNISYS, PCI_DEVICE_ID_UNISYS_DMA_DIRECTOR) },
+       { 0, }
+};
+
+struct ioat_device {
+       struct pci_dev          *pdev;
+       void __iomem            *iobase;
+       struct ioatdma_device   *dma;
+};
+
+static int __devinit ioat_probe(struct pci_dev *pdev,
+                               const struct pci_device_id *id);
+#ifdef IOAT_DMA_REMOVE
+static void __devexit ioat_remove(struct pci_dev *pdev);
+#endif
+
+static int ioat_setup_functionality(struct pci_dev *pdev, void __iomem *iobase)
+{
+       struct ioat_device *device = pci_get_drvdata(pdev);
+       u8 version;
+       int err = 0;
+
+       version = readb(iobase + IOAT_VER_OFFSET);
+       switch (version) {
+       case IOAT_VER_1_2:
+               device->dma = ioat_dma_probe(pdev, iobase);
+               break;
+       default:
+               err = -ENODEV;
+               break;
+       }
+       return err;
+}
+
+static void ioat_shutdown_functionality(struct pci_dev *pdev)
+{
+       struct ioat_device *device = pci_get_drvdata(pdev);
+
+       if (device->dma) {
+               ioat_dma_remove(device->dma);
+               device->dma = NULL;
+       }
+}
+
+static struct pci_driver ioat_pci_drv = {
+       .name           = "ioatdma",
+       .id_table       = ioat_pci_tbl,
+       .probe          = ioat_probe,
+       .shutdown       = ioat_shutdown_functionality,
+#ifdef IOAT_DMA_REMOVE
+       .remove         = __devexit_p(ioat_remove),
+#endif
+};
+
+static int __devinit ioat_probe(struct pci_dev *pdev,
+                               const struct pci_device_id *id)
+{
+       void __iomem *iobase;
+       struct ioat_device *device;
+       unsigned long mmio_start, mmio_len;
+       int err;
+
+       err = pci_enable_device(pdev);
+       if (err)
+               goto err_enable_device;
+
+       err = pci_request_regions(pdev, ioat_pci_drv.name);
+       if (err)
+               goto err_request_regions;
+
+       err = pci_set_dma_mask(pdev, DMA_64BIT_MASK);
+       if (err)
+               err = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
+       if (err)
+               goto err_set_dma_mask;
+
+       err = pci_set_consistent_dma_mask(pdev, DMA_64BIT_MASK);
+       if (err)
+               err = pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK);
+       if (err)
+               goto err_set_dma_mask;
+
+       mmio_start = pci_resource_start(pdev, 0);
+       mmio_len = pci_resource_len(pdev, 0);
+       iobase = ioremap(mmio_start, mmio_len);
+       if (!iobase) {
+               err = -ENOMEM;
+               goto err_ioremap;
+       }
+
+       device = kzalloc(sizeof(*device), GFP_KERNEL);
+       if (!device) {
+               err = -ENOMEM;
+               goto err_kzalloc;
+       }
+       device->pdev = pdev;
+       pci_set_drvdata(pdev, device);
+       device->iobase = iobase;
+
+       pci_set_master(pdev);
+
+       err = ioat_setup_functionality(pdev, iobase);
+       if (err)
+               goto err_version;
+
+       return 0;
+
+err_version:
+       kfree(device);
+err_kzalloc:
+       iounmap(iobase);
+err_ioremap:
+err_set_dma_mask:
+       pci_release_regions(pdev);
+       pci_disable_device(pdev);
+err_request_regions:
+err_enable_device:
+       return err;
+}
+
+#ifdef IOAT_DMA_REMOVE
+/*
+ * It is unsafe to remove this module: if removed while a requested
+ * dma is outstanding, esp. from tcp, it is possible to hang while
+ * waiting for something that will never finish, thus hanging at
+ * least one cpu.  However, if you're feeling lucky and need to do
+ * some testing, this usually works just fine.
+ */
+static void __devexit ioat_remove(struct pci_dev *pdev)
+{
+       struct ioat_device *device = pci_get_drvdata(pdev);
+
+       ioat_shutdown_functionality(pdev);
+
+       kfree(device);
+
+       iounmap(device->iobase);
+       pci_release_regions(pdev);
+       pci_disable_device(pdev);
+}
+#endif
+
+static int __init ioat_init_module(void)
+{
+       return pci_register_driver(&ioat_pci_drv);
+}
+module_init(ioat_init_module);
+
+static void __exit ioat_exit_module(void)
+{
+       pci_unregister_driver(&ioat_pci_drv);
+}
+module_exit(ioat_exit_module);
index 2db05f614843401454ef54229a728f33be4265ae..eef83ea291a3038337b1316e6e80a2a71db9d4a4 100644 (file)
 #define INITIAL_IOAT_DESC_COUNT 128
 
 #define to_ioat_chan(chan) container_of(chan, struct ioat_dma_chan, common)
-#define to_ioat_device(dev) container_of(dev, struct ioat_device, common)
+#define to_ioatdma_device(dev) container_of(dev, struct ioatdma_device, common)
 #define to_ioat_desc(lh) container_of(lh, struct ioat_desc_sw, node)
 #define tx_to_ioat_desc(tx) container_of(tx, struct ioat_desc_sw, async_tx)
 
 /* internal functions */
 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 int __devinit ioat_probe(struct pci_dev *pdev,
-                               const struct pci_device_id *ent);
-static void ioat_shutdown(struct pci_dev *pdev);
-static void __devexit ioat_remove(struct pci_dev *pdev);
 
-static int ioat_dma_enumerate_channels(struct ioat_device *device)
+static int ioat_dma_enumerate_channels(struct ioatdma_device *device)
 {
        u8 xfercap_scale;
        u32 xfercap;
@@ -158,17 +154,17 @@ static struct ioat_desc_sw *ioat_dma_alloc_descriptor(
 {
        struct ioat_dma_descriptor *desc;
        struct ioat_desc_sw *desc_sw;
-       struct ioat_device *ioat_device;
+       struct ioatdma_device *ioatdma_device;
        dma_addr_t phys;
 
-       ioat_device = to_ioat_device(ioat_chan->common.device);
-       desc = pci_pool_alloc(ioat_device->dma_pool, flags, &phys);
+       ioatdma_device = to_ioatdma_device(ioat_chan->common.device);
+       desc = pci_pool_alloc(ioatdma_device->dma_pool, flags, &phys);
        if (unlikely(!desc))
                return NULL;
 
        desc_sw = kzalloc(sizeof(*desc_sw), flags);
        if (unlikely(!desc_sw)) {
-               pci_pool_free(ioat_device->dma_pool, desc, phys);
+               pci_pool_free(ioatdma_device->dma_pool, desc, phys);
                return NULL;
        }
 
@@ -245,9 +241,8 @@ static int ioat_dma_alloc_chan_resources(struct dma_chan *chan)
 static void ioat_dma_free_chan_resources(struct dma_chan *chan)
 {
        struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
-       struct ioat_device *ioat_device = to_ioat_device(chan->device);
+       struct ioatdma_device *ioatdma_device = to_ioatdma_device(chan->device);
        struct ioat_desc_sw *desc, *_desc;
-       u16 chanctrl;
        int in_use_descs = 0;
 
        ioat_dma_memcpy_cleanup(ioat_chan);
@@ -258,19 +253,19 @@ static void ioat_dma_free_chan_resources(struct dma_chan *chan)
        list_for_each_entry_safe(desc, _desc, &ioat_chan->used_desc, node) {
                in_use_descs++;
                list_del(&desc->node);
-               pci_pool_free(ioat_device->dma_pool, desc->hw,
+               pci_pool_free(ioatdma_device->dma_pool, desc->hw,
                              desc->async_tx.phys);
                kfree(desc);
        }
        list_for_each_entry_safe(desc, _desc, &ioat_chan->free_desc, node) {
                list_del(&desc->node);
-               pci_pool_free(ioat_device->dma_pool, desc->hw,
+               pci_pool_free(ioatdma_device->dma_pool, desc->hw,
                              desc->async_tx.phys);
                kfree(desc);
        }
        spin_unlock_bh(&ioat_chan->desc_lock);
 
-       pci_pool_free(ioat_device->completion_pool,
+       pci_pool_free(ioatdma_device->completion_pool,
                      ioat_chan->completion_virt,
                      ioat_chan->completion_addr);
 
@@ -514,25 +509,9 @@ static enum dma_status ioat_dma_is_complete(struct dma_chan *chan,
 
 /* PCI API */
 
-static struct pci_device_id ioat_pci_tbl[] = {
-       { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT) },
-       { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_CNB)  },
-       { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SCNB) },
-       { PCI_DEVICE(PCI_VENDOR_ID_UNISYS, PCI_DEVICE_ID_UNISYS_DMA_DIRECTOR) },
-       { 0, }
-};
-
-static struct pci_driver ioat_pci_driver = {
-       .name   = "ioatdma",
-       .id_table = ioat_pci_tbl,
-       .probe  = ioat_probe,
-       .shutdown = ioat_shutdown,
-       .remove = __devexit_p(ioat_remove),
-};
-
 static irqreturn_t ioat_do_interrupt(int irq, void *data)
 {
-       struct ioat_device *instance = data;
+       struct ioatdma_device *instance = data;
        unsigned long attnstatus;
        u8 intrctrl;
 
@@ -592,7 +571,7 @@ static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan)
  */
 #define IOAT_TEST_SIZE 2000
 
-static int ioat_self_test(struct ioat_device *device)
+static int ioat_self_test(struct ioatdma_device *device)
 {
        int i;
        u8 *src;
@@ -660,46 +639,25 @@ out:
        return err;
 }
 
-static int __devinit ioat_probe(struct pci_dev *pdev,
-                               const struct pci_device_id *ent)
+struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev,
+                                     void __iomem *iobase)
 {
        int err;
-       unsigned long mmio_start, mmio_len;
-       void __iomem *reg_base;
-       struct ioat_device *device;
-
-       err = pci_enable_device(pdev);
-       if (err)
-               goto err_enable_device;
-
-       err = pci_set_dma_mask(pdev, DMA_64BIT_MASK);
-       if (err)
-               err = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
-       if (err)
-               goto err_set_dma_mask;
-
-       err = pci_request_regions(pdev, ioat_pci_driver.name);
-       if (err)
-               goto err_request_regions;
-
-       mmio_start = pci_resource_start(pdev, 0);
-       mmio_len = pci_resource_len(pdev, 0);
-
-       reg_base = ioremap(mmio_start, mmio_len);
-       if (!reg_base) {
-               err = -ENOMEM;
-               goto err_ioremap;
-       }
+       struct ioatdma_device *device;
 
        device = kzalloc(sizeof(*device), GFP_KERNEL);
        if (!device) {
                err = -ENOMEM;
                goto err_kzalloc;
        }
+       device->pdev = pdev;
+       device->reg_base = iobase;
+       device->version = readb(device->reg_base + IOAT_VER_OFFSET);
 
        /* DMA coherent memory pool for DMA descriptor allocations */
        device->dma_pool = pci_pool_create("dma_desc_pool", pdev,
-               sizeof(struct ioat_dma_descriptor), 64, 0);
+                                          sizeof(struct ioat_dma_descriptor),
+                                          64, 0);
        if (!device->dma_pool) {
                err = -ENOMEM;
                goto err_dma_pool;
@@ -713,26 +671,6 @@ static int __devinit ioat_probe(struct pci_dev *pdev,
                goto err_completion_pool;
        }
 
-       device->pdev = pdev;
-       pci_set_drvdata(pdev, device);
-#ifdef CONFIG_PCI_MSI
-       if (pci_enable_msi(pdev) == 0) {
-               device->msi = 1;
-       } else {
-               device->msi = 0;
-       }
-#endif
-       err = request_irq(pdev->irq, &ioat_do_interrupt, IRQF_SHARED, "ioat",
-               device);
-       if (err)
-               goto err_irq;
-
-       device->reg_base = reg_base;
-
-       writeb(IOAT_INTRCTRL_MASTER_INT_EN,
-              device->reg_base + IOAT_INTRCTRL_OFFSET);
-       pci_set_master(pdev);
-
        INIT_LIST_HEAD(&device->common.channels);
        ioat_dma_enumerate_channels(device);
 
@@ -746,9 +684,19 @@ static int __devinit ioat_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\n",
-                device->common.chancnt);
+       printk(KERN_INFO "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);
+       if (err)
+               goto err_irq;
+
+       writeb(IOAT_INTRCTRL_MASTER_INT_EN,
+              device->reg_base + IOAT_INTRCTRL_OFFSET);
+       pci_set_master(pdev);
 
        err = ioat_self_test(device);
        if (err)
@@ -756,9 +704,10 @@ static int __devinit ioat_probe(struct pci_dev *pdev,
 
        dma_async_device_register(&device->common);
 
-       return 0;
+       return device;
 
 err_self_test:
+       free_irq(device->pdev->irq, device);
 err_irq:
        pci_pool_destroy(device->completion_pool);
 err_completion_pool:
@@ -766,47 +715,24 @@ err_completion_pool:
 err_dma_pool:
        kfree(device);
 err_kzalloc:
-       iounmap(reg_base);
-err_ioremap:
-       pci_release_regions(pdev);
-err_request_regions:
-err_set_dma_mask:
-       pci_disable_device(pdev);
-err_enable_device:
-
-       printk(KERN_INFO
-               "ioatdma: Intel(R) I/OAT DMA Engine initialization failed\n");
-
-       return err;
-}
-
-static void ioat_shutdown(struct pci_dev *pdev)
-{
-       struct ioat_device *device;
-       device = pci_get_drvdata(pdev);
-
-       dma_async_device_unregister(&device->common);
+       iounmap(iobase);
+       printk(KERN_ERR
+              "ioatdma: Intel(R) I/OAT DMA Engine initialization failed\n");
+       return NULL;
 }
 
-static void __devexit ioat_remove(struct pci_dev *pdev)
+void ioat_dma_remove(struct ioatdma_device *device)
 {
-       struct ioat_device *device;
        struct dma_chan *chan, *_chan;
        struct ioat_dma_chan *ioat_chan;
 
-       device = pci_get_drvdata(pdev);
        dma_async_device_unregister(&device->common);
 
        free_irq(device->pdev->irq, device);
-#ifdef CONFIG_PCI_MSI
-       if (device->msi)
-               pci_disable_msi(device->pdev);
-#endif
+
        pci_pool_destroy(device->dma_pool);
        pci_pool_destroy(device->completion_pool);
-       iounmap(device->reg_base);
-       pci_release_regions(pdev);
-       pci_disable_device(pdev);
+
        list_for_each_entry_safe(chan, _chan,
                                 &device->common.channels, device_node) {
                ioat_chan = to_ioat_chan(chan);
@@ -816,25 +742,3 @@ static void __devexit ioat_remove(struct pci_dev *pdev)
        kfree(device);
 }
 
-/* MODULE API */
-MODULE_VERSION("1.9");
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Intel Corporation");
-
-static int __init ioat_init_module(void)
-{
-       /* it's currently unsafe to unload this module */
-       /* if forced, worst case is that rmmod hangs */
-       __unsafe(THIS_MODULE);
-
-       return pci_register_driver(&ioat_pci_driver);
-}
-
-module_init(ioat_init_module);
-
-static void __exit ioat_exit_module(void)
-{
-       pci_unregister_driver(&ioat_pci_driver);
-}
-
-module_exit(ioat_exit_module);
index bf4dad70e0f59b78b328e1fb4fe8e60240d8fe7a..0b8ffbde1e610d53d0ebd7db849ac0b811749d20 100644 (file)
 #define IOAT_LOW_COMPLETION_MASK       0xffffffc0
 
 /**
- * struct ioat_device - internal representation of a IOAT device
+ * struct ioatdma_device - internal representation of a IOAT device
  * @pdev: PCI-Express device
  * @reg_base: MMIO register space base address
  * @dma_pool: for allocating DMA descriptors
  * @common: embedded struct dma_device
- * @msi: Message Signaled Interrupt number
+ * @version: version of ioatdma device
  */
 
-struct ioat_device {
+struct ioatdma_device {
        struct pci_dev *pdev;
        void __iomem *reg_base;
        struct pci_pool *dma_pool;
        struct pci_pool *completion_pool;
-
        struct dma_device common;
-       u8 msi;
+       u8 version;
 };
 
 /**
@@ -84,7 +83,7 @@ struct ioat_dma_chan {
 
        int pending;
 
-       struct ioat_device *device;
+       struct ioatdma_device *device;
        struct dma_chan common;
 
        dma_addr_t completion_addr;
@@ -117,4 +116,13 @@ struct ioat_desc_sw {
        struct dma_async_tx_descriptor async_tx;
 };
 
+#if defined(CONFIG_INTEL_IOATDMA) || defined(CONFIG_INTEL_IOATDMA_MODULE)
+struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev,
+                                     void __iomem *iobase);
+void ioat_dma_remove(struct ioatdma_device *device);
+#else
+#define ioat_dma_probe(pdev, iobase)    NULL
+#define ioat_dma_remove(device)         do { } while (0)
+#endif
+
 #endif /* IOATDMA_H */
index 4d7a12880be3d519089c1c4e4f01df9817bcc331..9e7434e1551f9b02ba5bae19dd96b55821622184 100644 (file)
@@ -27,7 +27,7 @@
 #define IOAT_PCI_RID                   0x00
 #define IOAT_PCI_SVID                  0x8086
 #define IOAT_PCI_SID                   0x8086
-#define IOAT_VER                       0x12    /* Version 1.2 */
+#define IOAT_VER_1_2                   0x12    /* Version 1.2 */
 
 struct ioat_dma_descriptor {
        uint32_t        size;