1 files changed, 438 insertions, 0 deletions

diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
new file mode 100644
index 000000000000..f727a09eb72f
--- /dev/null
+++ b/drivers/pci/ats.c
@@ -0,0 +1,438 @@
+/*
+ * drivers/pci/ats.c
+ *
+ * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com>
+ * Copyright (C) 2011 Advanced Micro Devices,
+ *
+ * PCI Express I/O Virtualization (IOV) support.
+ *   Address Translation Service 1.0
+ *   Page Request Interface added by Joerg Roedel <joerg.roedel@amd.com>
+ *   PASID support added by Joerg Roedel <joerg.roedel@amd.com>
+ */
+
+#include <linux/pci-ats.h>
+#include <linux/pci.h>
+
+#include "pci.h"
+
+static int ats_alloc_one(struct pci_dev *dev, int ps)
+{
+        int pos;
+        u16 cap;
+        struct pci_ats *ats;
+
+        pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ATS);
+        if (!pos)
+                return -ENODEV;
+
+        ats = kzalloc(sizeof(*ats), GFP_KERNEL);
+        if (!ats)
+                return -ENOMEM;
+
+        ats->pos = pos;
+        ats->stu = ps;
+        pci_read_config_word(dev, pos + PCI_ATS_CAP, &cap);
+        ats->qdep = PCI_ATS_CAP_QDEP(cap) ? PCI_ATS_CAP_QDEP(cap) :
+                                            PCI_ATS_MAX_QDEP;
+        dev->ats = ats;
+
+        return 0;
+}
+
+static void ats_free_one(struct pci_dev *dev)
+{
+        kfree(dev->ats);
+        dev->ats = NULL;
+}
+
+/**
+ * pci_enable_ats - enable the ATS capability
+ * @dev: the PCI device
+ * @ps: the IOMMU page shift
+ *
+ * Returns 0 on success, or negative on failure.
+ */
+int pci_enable_ats(struct pci_dev *dev, int ps)
+{
+        int rc;
+        u16 ctrl;
+
+        BUG_ON(dev->ats && dev->ats->is_enabled);
+
+        if (ps < PCI_ATS_MIN_STU)
+                return -EINVAL;
+
+        if (dev->is_physfn || dev->is_virtfn) {
+                struct pci_dev *pdev = dev->is_physfn ? dev : dev->physfn;
+
+                mutex_lock(&pdev->sriov->lock);
+                if (pdev->ats)
+                        rc = pdev->ats->stu == ps ? 0 : -EINVAL;
+                else
+                        rc = ats_alloc_one(pdev, ps);
+
+                if (!rc)
+                        pdev->ats->ref_cnt++;
+                mutex_unlock(&pdev->sriov->lock);
+                if (rc)
+                        return rc;
+        }
+
+        if (!dev->is_physfn) {
+                rc = ats_alloc_one(dev, ps);
+                if (rc)
+                        return rc;
+        }
+
+        ctrl = PCI_ATS_CTRL_ENABLE;
+        if (!dev->is_virtfn)
+                ctrl |= PCI_ATS_CTRL_STU(ps - PCI_ATS_MIN_STU);
+        pci_write_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, ctrl);
+
+        dev->ats->is_enabled = 1;
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(pci_enable_ats);
+
+/**
+ * pci_disable_ats - disable the ATS capability
+ * @dev: the PCI device
+ */
+void pci_disable_ats(struct pci_dev *dev)
+{
+        u16 ctrl;
+
+        BUG_ON(!dev->ats || !dev->ats->is_enabled);
+
+        pci_read_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, &ctrl);
+        ctrl &= ~PCI_ATS_CTRL_ENABLE;
+        pci_write_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, ctrl);
+
+        dev->ats->is_enabled = 0;
+
+        if (dev->is_physfn || dev->is_virtfn) {
+                struct pci_dev *pdev = dev->is_physfn ? dev : dev->physfn;
+
+                mutex_lock(&pdev->sriov->lock);
+                pdev->ats->ref_cnt--;
+                if (!pdev->ats->ref_cnt)
+                        ats_free_one(pdev);
+                mutex_unlock(&pdev->sriov->lock);
+        }
+
+        if (!dev->is_physfn)
+                ats_free_one(dev);
+}
+EXPORT_SYMBOL_GPL(pci_disable_ats);
+
+/**
+ * pci_ats_queue_depth - query the ATS Invalidate Queue Depth
+ * @dev: the PCI device
+ *
+ * Returns the queue depth on success, or negative on failure.
+ *
+ * The ATS spec uses 0 in the Invalidate Queue Depth field to
+ * indicate that the function can accept 32 Invalidate Request.
+ * But here we use the `real' values (i.e. 1~32) for the Queue
+ * Depth; and 0 indicates the function shares the Queue with
+ * other functions (doesn't exclusively own a Queue).
+ */
+int pci_ats_queue_depth(struct pci_dev *dev)
+{
+        int pos;
+        u16 cap;
+
+        if (dev->is_virtfn)
+                return 0;
+
+        if (dev->ats)
+                return dev->ats->qdep;
+
+        pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ATS);
+        if (!pos)
+                return -ENODEV;
+
+        pci_read_config_word(dev, pos + PCI_ATS_CAP, &cap);
+
+        return PCI_ATS_CAP_QDEP(cap) ? PCI_ATS_CAP_QDEP(cap) :
+                                       PCI_ATS_MAX_QDEP;
+}
+EXPORT_SYMBOL_GPL(pci_ats_queue_depth);
+
+#ifdef CONFIG_PCI_PRI
+/**
+ * pci_enable_pri - Enable PRI capability
+ * @ pdev: PCI device structure
+ *
+ * Returns 0 on success, negative value on error
+ */
+int pci_enable_pri(struct pci_dev *pdev, u32 reqs)
+{
+        u16 control, status;
+        u32 max_requests;
+        int pos;
+
+        pos = pci_find_ext_capability(pdev, PCI_PRI_CAP);
+        if (!pos)
+                return -EINVAL;
+
+        pci_read_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, &control);
+        pci_read_config_word(pdev, pos + PCI_PRI_STATUS_OFF,  &status);
+        if ((control & PCI_PRI_ENABLE) || !(status & PCI_PRI_STATUS_STOPPED))
+                return -EBUSY;
+
+        pci_read_config_dword(pdev, pos + PCI_PRI_MAX_REQ_OFF, &max_requests);
+        reqs = min(max_requests, reqs);
+        pci_write_config_dword(pdev, pos + PCI_PRI_ALLOC_REQ_OFF, reqs);
+
+        control |= PCI_PRI_ENABLE;
+        pci_write_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, control);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(pci_enable_pri);
+
+/**
+ * pci_disable_pri - Disable PRI capability
+ * @pdev: PCI device structure
+ *
+ * Only clears the enabled-bit, regardless of its former value
+ */
+void pci_disable_pri(struct pci_dev *pdev)
+{
+        u16 control;
+        int pos;
+
+        pos = pci_find_ext_capability(pdev, PCI_PRI_CAP);
+        if (!pos)
+                return;
+
+        pci_read_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, &control);
+        control &= ~PCI_PRI_ENABLE;
+        pci_write_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, control);
+}
+EXPORT_SYMBOL_GPL(pci_disable_pri);
+
+/**
+ * pci_pri_enabled - Checks if PRI capability is enabled
+ * @pdev: PCI device structure
+ *
+ * Returns true if PRI is enabled on the device, false otherwise
+ */
+bool pci_pri_enabled(struct pci_dev *pdev)
+{
+        u16 control;
+        int pos;
+
+        pos = pci_find_ext_capability(pdev, PCI_PRI_CAP);
+        if (!pos)
+                return false;
+
+        pci_read_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, &control);
+
+        return (control & PCI_PRI_ENABLE) ? true : false;
+}
+EXPORT_SYMBOL_GPL(pci_pri_enabled);
+
+/**
+ * pci_reset_pri - Resets device's PRI state
+ * @pdev: PCI device structure
+ *
+ * The PRI capability must be disabled before this function is called.
+ * Returns 0 on success, negative value on error.
+ */
+int pci_reset_pri(struct pci_dev *pdev)
+{
+        u16 control;
+        int pos;
+
+        pos = pci_find_ext_capability(pdev, PCI_PRI_CAP);
+        if (!pos)
+                return -EINVAL;
+
+        pci_read_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, &control);
+        if (control & PCI_PRI_ENABLE)
+                return -EBUSY;
+
+        control |= PCI_PRI_RESET;
+
+        pci_write_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, control);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(pci_reset_pri);
+
+/**
+ * pci_pri_stopped - Checks whether the PRI capability is stopped
+ * @pdev: PCI device structure
+ *
+ * Returns true if the PRI capability on the device is disabled and the
+ * device has no outstanding PRI requests, false otherwise. The device
+ * indicates this via the STOPPED bit in the status register of the
+ * capability.
+ * The device internal state can be cleared by resetting the PRI state
+ * with pci_reset_pri(). This can force the capability into the STOPPED
+ * state.
+ */
+bool pci_pri_stopped(struct pci_dev *pdev)
+{
+        u16 control, status;
+        int pos;
+
+        pos = pci_find_ext_capability(pdev, PCI_PRI_CAP);
+        if (!pos)
+                return true;
+
+        pci_read_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, &control);
+        pci_read_config_word(pdev, pos + PCI_PRI_STATUS_OFF,  &status);
+
+        if (control & PCI_PRI_ENABLE)
+                return false;
+
+        return (status & PCI_PRI_STATUS_STOPPED) ? true : false;
+}
+EXPORT_SYMBOL_GPL(pci_pri_stopped);
+
+/**
+ * pci_pri_status - Request PRI status of a device
+ * @pdev: PCI device structure
+ *
+ * Returns negative value on failure, status on success. The status can
+ * be checked against status-bits. Supported bits are currently:
+ * PCI_PRI_STATUS_RF:      Response failure
+ * PCI_PRI_STATUS_UPRGI:   Unexpected Page Request Group Index
+ * PCI_PRI_STATUS_STOPPED: PRI has stopped
+ */
+int pci_pri_status(struct pci_dev *pdev)
+{
+        u16 status, control;
+        int pos;
+
+        pos = pci_find_ext_capability(pdev, PCI_PRI_CAP);
+        if (!pos)
+                return -EINVAL;
+
+        pci_read_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, &control);
+        pci_read_config_word(pdev, pos + PCI_PRI_STATUS_OFF,  &status);
+
+        /* Stopped bit is undefined when enable == 1, so clear it */
+        if (control & PCI_PRI_ENABLE)
+                status &= ~PCI_PRI_STATUS_STOPPED;
+
+        return status;
+}
+EXPORT_SYMBOL_GPL(pci_pri_status);
+#endif /* CONFIG_PCI_PRI */
+
+#ifdef CONFIG_PCI_PASID
+/**
+ * pci_enable_pasid - Enable the PASID capability
+ * @pdev: PCI device structure
+ * @features: Features to enable
+ *
+ * Returns 0 on success, negative value on error. This function checks
+ * whether the features are actually supported by the device and returns
+ * an error if not.
+ */
+int pci_enable_pasid(struct pci_dev *pdev, int features)
+{
+        u16 control, supported;
+        int pos;
+
+        pos = pci_find_ext_capability(pdev, PCI_PASID_CAP);
+        if (!pos)
+                return -EINVAL;
+
+        pci_read_config_word(pdev, pos + PCI_PASID_CONTROL_OFF, &control);
+        pci_read_config_word(pdev, pos + PCI_PASID_CAP_OFF,     &supported);
+
+        if (!(supported & PCI_PASID_ENABLE))
+                return -EINVAL;
+
+        supported &= PCI_PASID_EXEC | PCI_PASID_PRIV;
+
+        /* User wants to enable anything unsupported? */
+        if ((supported & features) != features)
+                return -EINVAL;
+
+        control = PCI_PASID_ENABLE | features;
+
+        pci_write_config_word(pdev, pos + PCI_PASID_CONTROL_OFF, control);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(pci_enable_pasid);
+
+/**
+ * pci_disable_pasid - Disable the PASID capability
+ * @pdev: PCI device structure
+ *
+ */
+void pci_disable_pasid(struct pci_dev *pdev)
+{
+        u16 control = 0;
+        int pos;
+
+        pos = pci_find_ext_capability(pdev, PCI_PASID_CAP);
+        if (!pos)
+                return;
+
+        pci_write_config_word(pdev, pos + PCI_PASID_CONTROL_OFF, control);
+}
+EXPORT_SYMBOL_GPL(pci_disable_pasid);
+
+/**
+ * pci_pasid_features - Check which PASID features are supported
+ * @pdev: PCI device structure
+ *
+ * Returns a negative value when no PASI capability is present.
+ * Otherwise is returns a bitmask with supported features. Current
+ * features reported are:
+ * PCI_PASID_ENABLE - PASID capability can be enabled
+ * PCI_PASID_EXEC - Execute permission supported
+ * PCI_PASID_PRIV - Priviledged mode supported
+ */
+int pci_pasid_features(struct pci_dev *pdev)
+{
+        u16 supported;
+        int pos;
+
+        pos = pci_find_ext_capability(pdev, PCI_PASID_CAP);
+        if (!pos)
+                return -EINVAL;
+
+        pci_read_config_word(pdev, pos + PCI_PASID_CAP_OFF, &supported);
+
+        supported &= PCI_PASID_ENABLE | PCI_PASID_EXEC | PCI_PASID_PRIV;
+
+        return supported;
+}
+EXPORT_SYMBOL_GPL(pci_pasid_features);
+
+#define PASID_NUMBER_SHIFT      8
+#define PASID_NUMBER_MASK       (0x1f << PASID_NUMBER_SHIFT)
+/**
+ * pci_max_pasid - Get maximum number of PASIDs supported by device
+ * @pdev: PCI device structure
+ *
+ * Returns negative value when PASID capability is not present.
+ * Otherwise it returns the numer of supported PASIDs.
+ */
+int pci_max_pasids(struct pci_dev *pdev)
+{
+        u16 supported;
+        int pos;
+
+        pos = pci_find_ext_capability(pdev, PCI_PASID_CAP);
+        if (!pos)
+                return -EINVAL;
+
+        pci_read_config_word(pdev, pos + PCI_PASID_CAP_OFF, &supported);
+
+        supported = (supported & PASID_NUMBER_MASK) >> PASID_NUMBER_SHIFT;
+
+        return (1 << supported);
+}
+EXPORT_SYMBOL_GPL(pci_max_pasids);
+#endif /* CONFIG_PCI_PASID */