281 lines
7.8 KiB
C
281 lines
7.8 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* PCI Message Signaled Interrupt (MSI) - irqdomain support
|
|
*/
|
|
#include <linux/acpi_iort.h>
|
|
#include <linux/irqdomain.h>
|
|
#include <linux/of_irq.h>
|
|
|
|
#include "msi.h"
|
|
|
|
int pci_msi_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
|
|
{
|
|
struct irq_domain *domain;
|
|
|
|
domain = dev_get_msi_domain(&dev->dev);
|
|
if (domain && irq_domain_is_hierarchy(domain))
|
|
return msi_domain_alloc_irqs_descs_locked(domain, &dev->dev, nvec);
|
|
|
|
return pci_msi_legacy_setup_msi_irqs(dev, nvec, type);
|
|
}
|
|
|
|
void pci_msi_teardown_msi_irqs(struct pci_dev *dev)
|
|
{
|
|
struct irq_domain *domain;
|
|
|
|
domain = dev_get_msi_domain(&dev->dev);
|
|
if (domain && irq_domain_is_hierarchy(domain))
|
|
msi_domain_free_irqs_descs_locked(domain, &dev->dev);
|
|
else
|
|
pci_msi_legacy_teardown_msi_irqs(dev);
|
|
msi_free_msi_descs(&dev->dev);
|
|
}
|
|
|
|
/**
|
|
* pci_msi_domain_write_msg - Helper to write MSI message to PCI config space
|
|
* @irq_data: Pointer to interrupt data of the MSI interrupt
|
|
* @msg: Pointer to the message
|
|
*/
|
|
static void pci_msi_domain_write_msg(struct irq_data *irq_data, struct msi_msg *msg)
|
|
{
|
|
struct msi_desc *desc = irq_data_get_msi_desc(irq_data);
|
|
|
|
/*
|
|
* For MSI-X desc->irq is always equal to irq_data->irq. For
|
|
* MSI only the first interrupt of MULTI MSI passes the test.
|
|
*/
|
|
if (desc->irq == irq_data->irq)
|
|
__pci_write_msi_msg(desc, msg);
|
|
}
|
|
|
|
/**
|
|
* pci_msi_domain_calc_hwirq - Generate a unique ID for an MSI source
|
|
* @desc: Pointer to the MSI descriptor
|
|
*
|
|
* The ID number is only used within the irqdomain.
|
|
*/
|
|
static irq_hw_number_t pci_msi_domain_calc_hwirq(struct msi_desc *desc)
|
|
{
|
|
struct pci_dev *dev = msi_desc_to_pci_dev(desc);
|
|
|
|
return (irq_hw_number_t)desc->msi_index |
|
|
pci_dev_id(dev) << 11 |
|
|
((irq_hw_number_t)(pci_domain_nr(dev->bus) & 0xFFFFFFFF)) << 27;
|
|
}
|
|
|
|
static inline bool pci_msi_desc_is_multi_msi(struct msi_desc *desc)
|
|
{
|
|
return !desc->pci.msi_attrib.is_msix && desc->nvec_used > 1;
|
|
}
|
|
|
|
/**
|
|
* pci_msi_domain_check_cap - Verify that @domain supports the capabilities
|
|
* for @dev
|
|
* @domain: The interrupt domain to check
|
|
* @info: The domain info for verification
|
|
* @dev: The device to check
|
|
*
|
|
* Returns:
|
|
* 0 if the functionality is supported
|
|
* 1 if Multi MSI is requested, but the domain does not support it
|
|
* -ENOTSUPP otherwise
|
|
*/
|
|
static int pci_msi_domain_check_cap(struct irq_domain *domain,
|
|
struct msi_domain_info *info,
|
|
struct device *dev)
|
|
{
|
|
struct msi_desc *desc = msi_first_desc(dev, MSI_DESC_ALL);
|
|
|
|
/* Special handling to support __pci_enable_msi_range() */
|
|
if (pci_msi_desc_is_multi_msi(desc) &&
|
|
!(info->flags & MSI_FLAG_MULTI_PCI_MSI))
|
|
return 1;
|
|
|
|
if (desc->pci.msi_attrib.is_msix) {
|
|
if (!(info->flags & MSI_FLAG_PCI_MSIX))
|
|
return -ENOTSUPP;
|
|
|
|
if (info->flags & MSI_FLAG_MSIX_CONTIGUOUS) {
|
|
unsigned int idx = 0;
|
|
|
|
/* Check for gaps in the entry indices */
|
|
msi_for_each_desc(desc, dev, MSI_DESC_ALL) {
|
|
if (desc->msi_index != idx++)
|
|
return -ENOTSUPP;
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void pci_msi_domain_set_desc(msi_alloc_info_t *arg,
|
|
struct msi_desc *desc)
|
|
{
|
|
arg->desc = desc;
|
|
arg->hwirq = pci_msi_domain_calc_hwirq(desc);
|
|
}
|
|
|
|
static struct msi_domain_ops pci_msi_domain_ops_default = {
|
|
.set_desc = pci_msi_domain_set_desc,
|
|
.msi_check = pci_msi_domain_check_cap,
|
|
};
|
|
|
|
static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
|
|
{
|
|
struct msi_domain_ops *ops = info->ops;
|
|
|
|
if (ops == NULL) {
|
|
info->ops = &pci_msi_domain_ops_default;
|
|
} else {
|
|
if (ops->set_desc == NULL)
|
|
ops->set_desc = pci_msi_domain_set_desc;
|
|
if (ops->msi_check == NULL)
|
|
ops->msi_check = pci_msi_domain_check_cap;
|
|
}
|
|
}
|
|
|
|
static void pci_msi_domain_update_chip_ops(struct msi_domain_info *info)
|
|
{
|
|
struct irq_chip *chip = info->chip;
|
|
|
|
BUG_ON(!chip);
|
|
if (!chip->irq_write_msi_msg)
|
|
chip->irq_write_msi_msg = pci_msi_domain_write_msg;
|
|
if (!chip->irq_mask)
|
|
chip->irq_mask = pci_msi_mask_irq;
|
|
if (!chip->irq_unmask)
|
|
chip->irq_unmask = pci_msi_unmask_irq;
|
|
}
|
|
|
|
/**
|
|
* pci_msi_create_irq_domain - Create a MSI interrupt domain
|
|
* @fwnode: Optional fwnode of the interrupt controller
|
|
* @info: MSI domain info
|
|
* @parent: Parent irq domain
|
|
*
|
|
* Updates the domain and chip ops and creates a MSI interrupt domain.
|
|
*
|
|
* Returns:
|
|
* A domain pointer or NULL in case of failure.
|
|
*/
|
|
struct irq_domain *pci_msi_create_irq_domain(struct fwnode_handle *fwnode,
|
|
struct msi_domain_info *info,
|
|
struct irq_domain *parent)
|
|
{
|
|
struct irq_domain *domain;
|
|
|
|
if (WARN_ON(info->flags & MSI_FLAG_LEVEL_CAPABLE))
|
|
info->flags &= ~MSI_FLAG_LEVEL_CAPABLE;
|
|
|
|
if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS)
|
|
pci_msi_domain_update_dom_ops(info);
|
|
if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
|
|
pci_msi_domain_update_chip_ops(info);
|
|
|
|
info->flags |= MSI_FLAG_ACTIVATE_EARLY | MSI_FLAG_DEV_SYSFS;
|
|
if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE))
|
|
info->flags |= MSI_FLAG_MUST_REACTIVATE;
|
|
|
|
/* PCI-MSI is oneshot-safe */
|
|
info->chip->flags |= IRQCHIP_ONESHOT_SAFE;
|
|
|
|
domain = msi_create_irq_domain(fwnode, info, parent);
|
|
if (!domain)
|
|
return NULL;
|
|
|
|
irq_domain_update_bus_token(domain, DOMAIN_BUS_PCI_MSI);
|
|
return domain;
|
|
}
|
|
EXPORT_SYMBOL_GPL(pci_msi_create_irq_domain);
|
|
|
|
/*
|
|
* Users of the generic MSI infrastructure expect a device to have a single ID,
|
|
* so with DMA aliases we have to pick the least-worst compromise. Devices with
|
|
* DMA phantom functions tend to still emit MSIs from the real function number,
|
|
* so we ignore those and only consider topological aliases where either the
|
|
* alias device or RID appears on a different bus number. We also make the
|
|
* reasonable assumption that bridges are walked in an upstream direction (so
|
|
* the last one seen wins), and the much braver assumption that the most likely
|
|
* case is that of PCI->PCIe so we should always use the alias RID. This echoes
|
|
* the logic from intel_irq_remapping's set_msi_sid(), which presumably works
|
|
* well enough in practice; in the face of the horrible PCIe<->PCI-X conditions
|
|
* for taking ownership all we can really do is close our eyes and hope...
|
|
*/
|
|
static int get_msi_id_cb(struct pci_dev *pdev, u16 alias, void *data)
|
|
{
|
|
u32 *pa = data;
|
|
u8 bus = PCI_BUS_NUM(*pa);
|
|
|
|
if (pdev->bus->number != bus || PCI_BUS_NUM(alias) != bus)
|
|
*pa = alias;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* pci_msi_domain_get_msi_rid - Get the MSI requester id (RID)
|
|
* @domain: The interrupt domain
|
|
* @pdev: The PCI device.
|
|
*
|
|
* The RID for a device is formed from the alias, with a firmware
|
|
* supplied mapping applied
|
|
*
|
|
* Returns: The RID.
|
|
*/
|
|
u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev)
|
|
{
|
|
struct device_node *of_node;
|
|
u32 rid = pci_dev_id(pdev);
|
|
|
|
pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);
|
|
|
|
of_node = irq_domain_get_of_node(domain);
|
|
rid = of_node ? of_msi_map_id(&pdev->dev, of_node, rid) :
|
|
iort_msi_map_id(&pdev->dev, rid);
|
|
|
|
return rid;
|
|
}
|
|
|
|
/**
|
|
* pci_msi_get_device_domain - Get the MSI domain for a given PCI device
|
|
* @pdev: The PCI device
|
|
*
|
|
* Use the firmware data to find a device-specific MSI domain
|
|
* (i.e. not one that is set as a default).
|
|
*
|
|
* Returns: The corresponding MSI domain or NULL if none has been found.
|
|
*/
|
|
struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev)
|
|
{
|
|
struct irq_domain *dom;
|
|
u32 rid = pci_dev_id(pdev);
|
|
|
|
pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);
|
|
dom = of_msi_map_get_device_domain(&pdev->dev, rid, DOMAIN_BUS_PCI_MSI);
|
|
if (!dom)
|
|
dom = iort_get_device_domain(&pdev->dev, rid,
|
|
DOMAIN_BUS_PCI_MSI);
|
|
return dom;
|
|
}
|
|
|
|
/**
|
|
* pci_dev_has_special_msi_domain - Check whether the device is handled by
|
|
* a non-standard PCI-MSI domain
|
|
* @pdev: The PCI device to check.
|
|
*
|
|
* Returns: True if the device irqdomain or the bus irqdomain is
|
|
* non-standard PCI/MSI.
|
|
*/
|
|
bool pci_dev_has_special_msi_domain(struct pci_dev *pdev)
|
|
{
|
|
struct irq_domain *dom = dev_get_msi_domain(&pdev->dev);
|
|
|
|
if (!dom)
|
|
dom = dev_get_msi_domain(&pdev->bus->dev);
|
|
|
|
if (!dom)
|
|
return true;
|
|
|
|
return dom->bus_token != DOMAIN_BUS_PCI_MSI;
|
|
}
|