Re: [PATCH v2 3/5] PCI: iproc: Disable MSI parsing in certain PAXC blocks

From: poza
Date: Tue Jun 12 2018 - 13:45:04 EST

On 2018-06-12 22:28, Ray Jui wrote:
On 6/12/2018 1:29 AM, poza@xxxxxxxxxxxxxx wrote:
On 2018-06-12 05:51, Ray Jui wrote:
The internal MSI parsing logic in certain revisions of PAXC root
complexes does not work properly and can casue corruptions on the
writes. They need to be disabled

Signed-off-by: Ray Jui <ray.jui@xxxxxxxxxxxx>
Reviewed-by: Scott Branden <scott.branden@xxxxxxxxxxxx>
Âdrivers/pci/host/pcie-iproc.c | 34 ++++++++++++++++++++++++++++++++--
Â1 file changed, 32 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c
index 680f6b1..0804aa2 100644
--- a/drivers/pci/host/pcie-iproc.c
+++ b/drivers/pci/host/pcie-iproc.c
@@ -1197,10 +1197,22 @@ static int iproc_pcie_paxb_v2_msi_steer(struct
iproc_pcie *pcie, u64 msi_addr)
ÂÂÂÂ return ret;

-static void iproc_pcie_paxc_v2_msi_steer(struct iproc_pcie *pcie, u64 msi_addr)
+static void iproc_pcie_paxc_v2_msi_steer(struct iproc_pcie *pcie, u64 msi_addr,
ÂÂÂÂ u32 val;

+ÂÂÂ if (!enable) {
+ÂÂÂÂÂÂÂÂ * Disable PAXC MSI steering. All write transfers will be
+ÂÂÂÂÂÂÂÂ * treated as non-MSI transfers
+ÂÂÂÂÂÂÂ val = iproc_pcie_read_reg(pcie, IPROC_PCIE_MSI_EN_CFG);
+ÂÂÂÂÂÂÂ iproc_pcie_write_reg(pcie, IPROC_PCIE_MSI_EN_CFG, val);
+ÂÂÂÂÂÂÂ return;
can be dropped.

No it cannot be dropped. Please review the code carefully.

Ahhh, my bad, it looked like a new function to me, may e I need sleep.
sorry about that.

Reviewed-by: Oza Pawandeep <poza@xxxxxxxxxxxxxx>