[SRU][Bionic][PATCH 1/2] UBUNTU: SAUCE: Revert "PCI/MSI: Enforce MSI[X] entry updates to be visible"

[Kleber Sacilotto de Souza]

BugLink: https://bugs.launchpad.net/bugs/1946149

This reverts commit 2478f358c2b35fea04e005447ce99ad8dc53fd5d.

Revert upstream commit b9255a7cb51754e8d2645b65dd31805e282b4f3e in a
preparation for reverting upstream commit
da181dc974ad667579baece33c2c8d2d1e4558d5 ("PCI/MSI: Enforce that MSI-X
table entry is masked for update") which is causing boot issues on some
platforms.

Signed-off-by: Kleber Sacilotto de Souza <kleber.souza at canonical.com>
---
 drivers/pci/msi.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 0b44d224f464..7497c37a1e48 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -322,9 +322,6 @@ void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 
 		if (unmasked)
 			__pci_msix_desc_mask_irq(entry, 0);
-
-		/* Ensure that the writes are visible in the device */
-		readl(base + PCI_MSIX_ENTRY_DATA);
 	} else {
 		int pos = dev->msi_cap;
 		u16 msgctl;
@@ -345,8 +342,6 @@ void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 			pci_write_config_word(dev, pos + PCI_MSI_DATA_32,
 					      msg->data);
 		}
-		/* Ensure that the writes are visible in the device */
-		pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &msgctl);
 	}
 	entry->msg = *msg;
 }
-- 
2.30.2