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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/pci/ats.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/pci/ats.c')
-rw-r--r-- | drivers/pci/ats.c | 396 |
1 files changed, 396 insertions, 0 deletions
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c new file mode 100644 index 000000000..5b78f3b1b --- /dev/null +++ b/drivers/pci/ats.c @@ -0,0 +1,396 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * 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> + * + * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com> + * Copyright (C) 2011 Advanced Micro Devices, + */ + +#include <linux/export.h> +#include <linux/pci-ats.h> +#include <linux/pci.h> +#include <linux/slab.h> + +#include "pci.h" + +void pci_ats_init(struct pci_dev *dev) +{ + int pos; + + if (pci_ats_disabled()) + return; + + pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ATS); + if (!pos) + return; + + dev->ats_cap = pos; +} + +/** + * 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) +{ + u16 ctrl; + struct pci_dev *pdev; + + if (!dev->ats_cap) + return -EINVAL; + + if (WARN_ON(dev->ats_enabled)) + return -EBUSY; + + if (ps < PCI_ATS_MIN_STU) + return -EINVAL; + + /* + * Note that enabling ATS on a VF fails unless it's already enabled + * with the same STU on the PF. + */ + ctrl = PCI_ATS_CTRL_ENABLE; + if (dev->is_virtfn) { + pdev = pci_physfn(dev); + if (pdev->ats_stu != ps) + return -EINVAL; + + atomic_inc(&pdev->ats_ref_cnt); /* count enabled VFs */ + } else { + dev->ats_stu = ps; + ctrl |= PCI_ATS_CTRL_STU(dev->ats_stu - PCI_ATS_MIN_STU); + } + pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl); + + dev->ats_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) +{ + struct pci_dev *pdev; + u16 ctrl; + + if (WARN_ON(!dev->ats_enabled)) + return; + + if (atomic_read(&dev->ats_ref_cnt)) + return; /* VFs still enabled */ + + if (dev->is_virtfn) { + pdev = pci_physfn(dev); + atomic_dec(&pdev->ats_ref_cnt); + } + + pci_read_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, &ctrl); + ctrl &= ~PCI_ATS_CTRL_ENABLE; + pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl); + + dev->ats_enabled = 0; +} +EXPORT_SYMBOL_GPL(pci_disable_ats); + +void pci_restore_ats_state(struct pci_dev *dev) +{ + u16 ctrl; + + if (!dev->ats_enabled) + return; + + ctrl = PCI_ATS_CTRL_ENABLE; + if (!dev->is_virtfn) + ctrl |= PCI_ATS_CTRL_STU(dev->ats_stu - PCI_ATS_MIN_STU); + pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl); +} +EXPORT_SYMBOL_GPL(pci_restore_ats_state); + +/** + * 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) +{ + u16 cap; + + if (!dev->ats_cap) + return -EINVAL; + + if (dev->is_virtfn) + return 0; + + pci_read_config_word(dev, dev->ats_cap + 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; + + if (WARN_ON(pdev->pri_enabled)) + return -EBUSY; + + pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI); + if (!pos) + return -EINVAL; + + pci_read_config_word(pdev, pos + PCI_PRI_STATUS, &status); + if (!(status & PCI_PRI_STATUS_STOPPED)) + return -EBUSY; + + pci_read_config_dword(pdev, pos + PCI_PRI_MAX_REQ, &max_requests); + reqs = min(max_requests, reqs); + pdev->pri_reqs_alloc = reqs; + pci_write_config_dword(pdev, pos + PCI_PRI_ALLOC_REQ, reqs); + + control = PCI_PRI_CTRL_ENABLE; + pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control); + + pdev->pri_enabled = 1; + + 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; + + if (WARN_ON(!pdev->pri_enabled)) + return; + + pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI); + if (!pos) + return; + + pci_read_config_word(pdev, pos + PCI_PRI_CTRL, &control); + control &= ~PCI_PRI_CTRL_ENABLE; + pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control); + + pdev->pri_enabled = 0; +} +EXPORT_SYMBOL_GPL(pci_disable_pri); + +/** + * pci_restore_pri_state - Restore PRI + * @pdev: PCI device structure + */ +void pci_restore_pri_state(struct pci_dev *pdev) +{ + u16 control = PCI_PRI_CTRL_ENABLE; + u32 reqs = pdev->pri_reqs_alloc; + int pos; + + if (!pdev->pri_enabled) + return; + + pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI); + if (!pos) + return; + + pci_write_config_dword(pdev, pos + PCI_PRI_ALLOC_REQ, reqs); + pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control); +} +EXPORT_SYMBOL_GPL(pci_restore_pri_state); + +/** + * 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; + + if (WARN_ON(pdev->pri_enabled)) + return -EBUSY; + + pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI); + if (!pos) + return -EINVAL; + + control = PCI_PRI_CTRL_RESET; + pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control); + + return 0; +} +EXPORT_SYMBOL_GPL(pci_reset_pri); +#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; + + if (WARN_ON(pdev->pasid_enabled)) + return -EBUSY; + + if (!pdev->eetlp_prefix_path) + return -EINVAL; + + pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); + if (!pos) + return -EINVAL; + + pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported); + supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV; + + /* User wants to enable anything unsupported? */ + if ((supported & features) != features) + return -EINVAL; + + control = PCI_PASID_CTRL_ENABLE | features; + pdev->pasid_features = features; + + pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control); + + pdev->pasid_enabled = 1; + + 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; + + if (WARN_ON(!pdev->pasid_enabled)) + return; + + pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); + if (!pos) + return; + + pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control); + + pdev->pasid_enabled = 0; +} +EXPORT_SYMBOL_GPL(pci_disable_pasid); + +/** + * pci_restore_pasid_state - Restore PASID capabilities + * @pdev: PCI device structure + */ +void pci_restore_pasid_state(struct pci_dev *pdev) +{ + u16 control; + int pos; + + if (!pdev->pasid_enabled) + return; + + pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); + if (!pos) + return; + + control = PCI_PASID_CTRL_ENABLE | pdev->pasid_features; + pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control); +} +EXPORT_SYMBOL_GPL(pci_restore_pasid_state); + +/** + * 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_CAP_EXEC - Execute permission supported + * PCI_PASID_CAP_PRIV - Privileged mode supported + */ +int pci_pasid_features(struct pci_dev *pdev) +{ + u16 supported; + int pos; + + pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); + if (!pos) + return -EINVAL; + + pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported); + + supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_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_EXT_CAP_ID_PASID); + if (!pos) + return -EINVAL; + + pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported); + + supported = (supported & PASID_NUMBER_MASK) >> PASID_NUMBER_SHIFT; + + return (1 << supported); +} +EXPORT_SYMBOL_GPL(pci_max_pasids); +#endif /* CONFIG_PCI_PASID */ |