powerpc/pseries/msi: Let core code check for contiguous entries

Set the domain info flag and remove the check.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NJason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20211210221814.720998720@linutronix.de

arch/powerpc/platforms/pseries/msi.c

@@ -321,27 +321,6 @@ static int msi_quota_for_device(struct pci_dev *dev, int request)
 	return request;
 }
 
-static int check_msix_entries(struct pci_dev *pdev)
-{
-	struct msi_desc *entry;
-	int expected;
-
-	/* There's no way for us to express to firmware that we want
-	 * a discontiguous, or non-zero based, range of MSI-X entries.
-	 * So we must reject such requests. */
-
-	expected = 0;
-	for_each_pci_msi_entry(entry, pdev) {
-		if (entry->msi_index != expected) {
-			pr_debug("rtas_msi: bad MSI-X entries.\n");
-			return -EINVAL;
-		}
-		expected++;
-	}
-
-	return 0;
-}
-
 static void rtas_hack_32bit_msi_gen2(struct pci_dev *pdev)
 {
 	u32 addr_hi, addr_lo;
@@ -380,9 +359,6 @@ static int rtas_prepare_msi_irqs(struct pci_dev *pdev, int nvec_in, int type,
 	if (quota && quota < nvec)
 		return quota;
 
-	if (type == PCI_CAP_ID_MSIX && check_msix_entries(pdev))
-		return -EINVAL;
-
 	/*
 	 * Firmware currently refuse any non power of two allocation
 	 * so we round up if the quota will allow it.
@@ -529,9 +505,16 @@ static struct irq_chip pseries_pci_msi_irq_chip = {
 	.irq_write_msi_msg	= pseries_msi_write_msg,
 };
 
+
+/*
+ * Set MSI_FLAG_MSIX_CONTIGUOUS as there is no way to express to
+ * firmware to request a discontiguous or non-zero based range of
+ * MSI-X entries. Core code will reject such setup attempts.
+ */
 static struct msi_domain_info pseries_msi_domain_info = {
 	.flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		  MSI_FLAG_MULTI_PCI_MSI  | MSI_FLAG_PCI_MSIX),
+		  MSI_FLAG_MULTI_PCI_MSI  | MSI_FLAG_PCI_MSIX |
+		  MSI_FLAG_MSIX_CONTIGUOUS),
 	.ops   = &pseries_pci_msi_domain_ops,
 	.chip  = &pseries_pci_msi_irq_chip,
 };