Commit 71020a3c authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

PCI/MSI: Use msi_add_msi_desc() 



Simplify the allocation of MSI descriptors by using msi_add_msi_desc()
which moves the storage handling to core code and prepares for dynamic
extension of the MSI-X vector space.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Tested-by: default avatarMichael Kelley <mikelley@microsoft.com>
Tested-by: default avatarNishanth Menon <nm@ti.com>
Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Acked-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20211206210748.035348646@linutronix.de
parent 5512c5ea

drivers/pci/msi/msi.c

+47 −57
Original line number Diff line number Diff line
@@ -376,40 +376,41 @@ static int pci_setup_msi_context(struct pci_dev *dev) 
	return ret;

}



static struct msi_desc *

msi_setup_entry(struct pci_dev *dev, int nvec, struct irq_affinity_desc *masks)

static int msi_setup_msi_desc(struct pci_dev *dev, int nvec,

			      struct irq_affinity_desc *masks)

{

	struct msi_desc *entry;

	struct msi_desc desc;

	u16 control;



	/* MSI Entry Initialization */

	entry = alloc_msi_entry(&dev->dev, nvec, masks);

	if (!entry)

		return NULL;

	memset(&desc, 0, sizeof(desc));



	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);

	/* Lies, damned lies, and MSIs */

	if (dev->dev_flags & PCI_DEV_FLAGS_HAS_MSI_MASKING)

		control |= PCI_MSI_FLAGS_MASKBIT;

	/* Respect XEN's mask disabling */

	if (pci_msi_ignore_mask)

		control &= ~PCI_MSI_FLAGS_MASKBIT;



	entry->pci.msi_attrib.is_64	= !!(control & PCI_MSI_FLAGS_64BIT);

	entry->pci.msi_attrib.can_mask	= !pci_msi_ignore_mask &&

					  !!(control & PCI_MSI_FLAGS_MASKBIT);

	entry->pci.msi_attrib.default_irq = dev->irq;

	entry->pci.msi_attrib.multi_cap	= (control & PCI_MSI_FLAGS_QMASK) >> 1;

	entry->pci.msi_attrib.multiple	= ilog2(__roundup_pow_of_two(nvec));

	desc.nvec_used			= nvec;

	desc.pci.msi_attrib.is_64	= !!(control & PCI_MSI_FLAGS_64BIT);

	desc.pci.msi_attrib.can_mask	= !!(control & PCI_MSI_FLAGS_MASKBIT);

	desc.pci.msi_attrib.default_irq	= dev->irq;

	desc.pci.msi_attrib.multi_cap	= (control & PCI_MSI_FLAGS_QMASK) >> 1;

	desc.pci.msi_attrib.multiple	= ilog2(__roundup_pow_of_two(nvec));

	desc.affinity			= masks;



	if (control & PCI_MSI_FLAGS_64BIT)

		entry->pci.mask_pos = dev->msi_cap + PCI_MSI_MASK_64;

		desc.pci.mask_pos = dev->msi_cap + PCI_MSI_MASK_64;

	else

		entry->pci.mask_pos = dev->msi_cap + PCI_MSI_MASK_32;

		desc.pci.mask_pos = dev->msi_cap + PCI_MSI_MASK_32;



	/* Save the initial mask status */

	if (entry->pci.msi_attrib.can_mask)

		pci_read_config_dword(dev, entry->pci.mask_pos, &entry->pci.msi_mask);



	if (desc.pci.msi_attrib.can_mask)

		pci_read_config_dword(dev, desc.pci.mask_pos, &desc.pci.msi_mask);



	return entry;

	return msi_add_msi_desc(&dev->dev, &desc);

}



static int msi_verify_entries(struct pci_dev *dev)
@@ -459,17 +460,14 @@ static int msi_capability_init(struct pci_dev *dev, int nvec, 
		masks = irq_create_affinity_masks(nvec, affd);



	msi_lock_descs(&dev->dev);

	entry = msi_setup_entry(dev, nvec, masks);

	if (!entry) {

		ret = -ENOMEM;

	ret = msi_setup_msi_desc(dev, nvec, masks);

	if (ret)

		goto fail;

	}



	/* All MSIs are unmasked by default; mask them all */

	entry = first_pci_msi_entry(dev);

	pci_msi_mask(entry, msi_multi_mask(entry));



	list_add_tail(&entry->list, dev_to_msi_list(&dev->dev));



	/* Configure MSI capability structure */

	ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI);

	if (ret)
@@ -519,48 +517,40 @@ static void __iomem *msix_map_region(struct pci_dev *dev, 
	return ioremap(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE);

}



static int msix_setup_entries(struct pci_dev *dev, void __iomem *base,

static int msix_setup_msi_descs(struct pci_dev *dev, void __iomem *base,

				struct msix_entry *entries, int nvec,

				struct irq_affinity_desc *masks)

{

	int i, vec_count = pci_msix_vec_count(dev);

	int ret = 0, i, vec_count = pci_msix_vec_count(dev);

	struct irq_affinity_desc *curmsk;

	struct msi_desc *entry;

	struct msi_desc desc;

	void __iomem *addr;



	for (i = 0, curmsk = masks; i < nvec; i++) {

		entry = alloc_msi_entry(&dev->dev, 1, curmsk);

		if (!entry) {

			/* No enough memory. Don't try again */

			return -ENOMEM;

		}



		entry->pci.msi_attrib.is_msix	= 1;

		entry->pci.msi_attrib.is_64	= 1;



		if (entries)

			entry->msi_index = entries[i].entry;

		else

			entry->msi_index = i;

	memset(&desc, 0, sizeof(desc));



		entry->pci.msi_attrib.is_virtual = entry->msi_index >= vec_count;

	desc.nvec_used			= 1;

	desc.pci.msi_attrib.is_msix	= 1;

	desc.pci.msi_attrib.is_64	= 1;

	desc.pci.msi_attrib.default_irq	= dev->irq;

	desc.pci.mask_base		= base;



		entry->pci.msi_attrib.can_mask	= !pci_msi_ignore_mask &&

						  !entry->pci.msi_attrib.is_virtual;

	for (i = 0, curmsk = masks; i < nvec; i++, curmsk++) {

		desc.msi_index = entries ? entries[i].entry : i;

		desc.affinity = masks ? curmsk : NULL;

		desc.pci.msi_attrib.is_virtual = desc.msi_index >= vec_count;

		desc.pci.msi_attrib.can_mask = !pci_msi_ignore_mask &&

					       !desc.pci.msi_attrib.is_virtual;



		entry->pci.msi_attrib.default_irq	= dev->irq;

		entry->pci.mask_base			= base;



		if (entry->pci.msi_attrib.can_mask) {

			addr = pci_msix_desc_addr(entry);

			entry->pci.msix_ctrl = readl(addr + PCI_MSIX_ENTRY_VECTOR_CTRL);

		if (!desc.pci.msi_attrib.can_mask) {

			addr = pci_msix_desc_addr(&desc);

			desc.pci.msix_ctrl = readl(addr + PCI_MSIX_ENTRY_VECTOR_CTRL);

		}



		list_add_tail(&entry->list, dev_to_msi_list(&dev->dev));

		if (masks)

			curmsk++;

		ret = msi_add_msi_desc(&dev->dev, &desc);

		if (ret)

			break;

	}

	return 0;

	return ret;

}



static void msix_update_entries(struct pci_dev *dev, struct msix_entry *entries)
@@ -598,7 +588,7 @@ static int msix_setup_interrupts(struct pci_dev *dev, void __iomem *base, 
		masks = irq_create_affinity_masks(nvec, affd);



	msi_lock_descs(&dev->dev);

	ret = msix_setup_entries(dev, base, entries, nvec, masks);

	ret = msix_setup_msi_descs(dev, base, entries, nvec, masks);

	if (ret)

		goto out_free;