From e9a75f2de97d3709f668af6370395925a2c8800f Mon Sep 17 00:00:00 2001
From: Niklas Cassel <cassel@kernel.org>
Date: Sat, 16 Nov 2024 01:59:51 +0100
Subject: [PATCH] PCI: dwc: ep: Fix advertised resizable BAR size regression
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commit 118397c9baaac0b7ec81896f8d755d09aa82c485 upstream.

The advertised resizable BAR size was fixed in commit 72e34b8593e0 ("PCI:
dwc: endpoint: Fix advertised resizable BAR size").

Commit 867ab111b242 ("PCI: dwc: ep: Add a generic dw_pcie_ep_linkdown()
API to handle Link Down event") was included shortly after this, and
moved the code to another function. When the code was moved, this fix
was mistakenly lost.

According to the spec, it is illegal to not have a bit set in
PCI_REBAR_CAP, and 1 MB is the smallest size allowed.

So, set bit 4 in PCI_REBAR_CAP, so that we actually advertise support
for a 1 MB BAR size.

Fixes: 867ab111b242 ("PCI: dwc: ep: Add a generic dw_pcie_ep_linkdown() API to handle Link Down event")
Link: https://lore.kernel.org/r/20241116005950.2480427-2-cassel@kernel.org
Link: https://lore.kernel.org/r/20240606-pci-deinit-v1-3-4395534520dc@linaro.org
Link: https://lore.kernel.org/r/20240307111520.3303774-1-cassel@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/pci/controller/dwc/pcie-designware-ep.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 43ba5c6738df1..cc8ff4a014368 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -689,7 +689,7 @@ static void dw_pcie_ep_init_non_sticky_registers(struct dw_pcie *pci)
 		 * for 1 MB BAR size only.
 		 */
 		for (i = 0; i < nbars; i++, offset += PCI_REBAR_CTRL)
-			dw_pcie_writel_dbi(pci, offset + PCI_REBAR_CAP, 0x0);
+			dw_pcie_writel_dbi(pci, offset + PCI_REBAR_CAP, BIT(4));
 	}
 
 	dw_pcie_setup(pci);
-- 
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