From d60a2e281e9de2b2f67343b2e39417ca0f4fd54e Mon Sep 17 00:00:00 2001

From: Serge Semin <Sergey.Semin@baikalelectronics.ru>

Date: Fri, 24 Jun 2022 17:34:13 +0300

Subject: [PATCH] PCI: dwc: Disable outbound windows only for controllers using iATU

Git-commit: d60a2e281e9de2b2f67343b2e39417ca0f4fd54e

Patch-mainline: v6.0-rc1

References: git-fixes

Some DWC-based controllers (e.g., pcie-al.c and pci-keystone.c, identified

by the fact that they override the default dw_child_pcie_ops) use their own

address translation approach instead of the DWC internal ATU (iATU).  For

those controllers, skip disabling the iATU outbound windows.

[bhelgaas: commit log, update multiple window comment]

Fixes: 458ad06c4cdd ("PCI: dwc: Ensure all outbound ATU windows are reset")

Link: https://lore.kernel.org/r/20220624143428.8334-4-Sergey.Semin@baikalelectronics.ru

Tested-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Reviewed-by: Rob Herring <robh@kernel.org>

Acked-by: Takashi Iwai <tiwai@suse.de>

---

 drivers/pci/controller/dwc/pcie-designware-host.c | 14 ++++++++------

 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c

index bc9a7df130ef..d0d768f22ac3 100644

--- a/drivers/pci/controller/dwc/pcie-designware-host.c

+++ b/drivers/pci/controller/dwc/pcie-designware-host.c

@@ -543,7 +543,6 @@ static struct pci_ops dw_pcie_ops = {

 void dw_pcie_setup_rc(struct pcie_port *pp)

 {

-	int i;

 	u32 val, ctrl, num_ctrls;

 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);

@@ -594,19 +593,22 @@ void dw_pcie_setup_rc(struct pcie_port *pp)

 		PCI_COMMAND_MASTER | PCI_COMMAND_SERR;

 	dw_pcie_writel_dbi(pci, PCI_COMMAND, val);

-	/* Ensure all outbound windows are disabled so there are multiple matches */

-	for (i = 0; i < pci->num_ob_windows; i++)

-		dw_pcie_disable_atu(pci, i, DW_PCIE_REGION_OUTBOUND);

-

 	/*

 	 * If the platform provides its own child bus config accesses, it means

 	 * the platform uses its own address translation component rather than

 	 * ATU, so we should not program the ATU here.

 	 */

 	if (pp->bridge->child_ops == &dw_child_pcie_ops) {

-		int atu_idx = 0;

+		int i, atu_idx = 0;

 		struct resource_entry *entry;

+		/*

+		 * Disable all outbound windows to make sure a transaction

+		 * can't match multiple windows.

+		 */

+		for (i = 0; i < pci->num_ob_windows; i++)

+			dw_pcie_disable_atu(pci, i, DW_PCIE_REGION_OUTBOUND);

+

 		/* Get last memory resource entry */

 		resource_list_for_each_entry(entry, &pp->bridge->windows) {

 			if (resource_type(entry->res) != IORESOURCE_MEM)

-- 

2.35.3