Commit c7ecb95c authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

PCI/MSI: Set pci_dev::msi[x]_enabled early 



There are quite some places which retrieve the first MSI descriptor to
evaluate whether the setup is for MSI or MSI-X. That's required because
pci_dev::msi[x]_enabled is only set when the setup completed successfully.

There is no real reason why msi[x]_enabled can't be set at the beginning of
the setup sequence and cleared in case of a failure.

Implement that so the MSI descriptor evaluations can be converted to simple
property queries.

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>
Link: https://lore.kernel.org/r/20211210221813.250049810@linutronix.de
parent 91f7d2db

drivers/pci/msi/msi.c

+17 −6
Original line number Diff line number Diff line
@@ -421,11 +421,18 @@ static int msi_capability_init(struct pci_dev *dev, int nvec, 
	struct msi_desc *entry;

	int ret;



	pci_msi_set_enable(dev, 0);	/* Disable MSI during set up */

	/*

	 * Disable MSI during setup in the hardware, but mark it enabled

	 * so that setup code can evaluate it.

	 */

	pci_msi_set_enable(dev, 0);

	dev->msi_enabled = 1;



	entry = msi_setup_entry(dev, nvec, affd);

	if (!entry)

		return -ENOMEM;

	if (!entry) {

		ret = -ENOMEM;

		goto fail;

	}



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

	pci_msi_mask(entry, msi_multi_mask(entry));
@@ -452,7 +459,6 @@ static int msi_capability_init(struct pci_dev *dev, int nvec, 
	/* Set MSI enabled bits	*/

	pci_intx_for_msi(dev, 0);

	pci_msi_set_enable(dev, 1);

	dev->msi_enabled = 1;



	pcibios_free_irq(dev);

	dev->irq = entry->irq;
@@ -461,6 +467,8 @@ static int msi_capability_init(struct pci_dev *dev, int nvec, 
err:

	pci_msi_unmask(entry, msi_multi_mask(entry));

	free_msi_irqs(dev);

fail:

	dev->msi_enabled = 0;

	return ret;

}
@@ -589,6 +597,9 @@ static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries, 
	pci_msix_clear_and_set_ctrl(dev, 0, PCI_MSIX_FLAGS_MASKALL |

				    PCI_MSIX_FLAGS_ENABLE);



	/* Mark it enabled so setup functions can query it */

	dev->msix_enabled = 1;



	pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control);

	/* Request & Map MSI-X table region */

	tsize = msix_table_size(control);
@@ -623,9 +634,8 @@ static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries, 


	dev->msi_irq_groups = groups;



	/* Set MSI-X enabled bits and unmask the function */

	/* Disable INTX */

	pci_intx_for_msi(dev, 0);

	dev->msix_enabled = 1;



	/*

	 * Ensure that all table entries are masked to prevent
@@ -645,6 +655,7 @@ static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries, 
	free_msi_irqs(dev);



out_disable:

	dev->msix_enabled = 0;

	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE, 0);



	return ret;