releases/6.12.23/pci-cadence-ep-fix-the-driver-to-send-msg-tlp-for-in.patch

From 87a5801026d24daaccd7e3530901c50f5a3082ae Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Sat, 15 Feb 2025 00:57:24 +0800
Subject: PCI: cadence-ep: Fix the driver to send MSG TLP for INTx without data
 payload
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From: Hans Zhang <18255117159@163.com>

[ Upstream commit 3ac47fbf4f6e8c3a7c3855fac68cc3246f90f850 ]

Per the Cadence's "PCIe Controller IP for AX14" user guide, Version
1.04, Section 9.1.7.1, "AXI Subordinate to PCIe Address Translation
Registers", Table 9.4, the bit 16 of the AXI Subordinate Address
(axi_s_awaddr) when set corresponds to MSG with data, and when not set,
to MSG without data.

However, the driver is currently doing the opposite and due to this,
the INTx is never received on the host.

So, fix the driver to reflect the documentation and also make INTx work.

Fixes: 37dddf14f1ae ("PCI: cadence: Add EndPoint Controller driver for Cadence PCIe controller")
Signed-off-by: Hans Zhang <18255117159@163.com>
Signed-off-by: Hans Zhang <hans.zhang@cixtech.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20250214165724.184599-1-18255117159@163.com
[kwilczynski: commit log]
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/pci/controller/cadence/pcie-cadence-ep.c | 3 +--
 drivers/pci/controller/cadence/pcie-cadence.h    | 2 +-
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c
index e0cc4560dfde7..0bf4cde34f517 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-ep.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c
@@ -352,8 +352,7 @@ static void cdns_pcie_ep_assert_intx(struct cdns_pcie_ep *ep, u8 fn, u8 intx,
 	spin_unlock_irqrestore(&ep->lock, flags);
 
 	offset = CDNS_PCIE_NORMAL_MSG_ROUTING(MSG_ROUTING_LOCAL) |
-		 CDNS_PCIE_NORMAL_MSG_CODE(msg_code) |
-		 CDNS_PCIE_MSG_NO_DATA;
+		 CDNS_PCIE_NORMAL_MSG_CODE(msg_code);
 	writel(0, ep->irq_cpu_addr + offset);
 }
 
diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
index f5eeff834ec19..39ee9945c903e 100644
--- a/drivers/pci/controller/cadence/pcie-cadence.h
+++ b/drivers/pci/controller/cadence/pcie-cadence.h
@@ -246,7 +246,7 @@ struct cdns_pcie_rp_ib_bar {
 #define CDNS_PCIE_NORMAL_MSG_CODE_MASK		GENMASK(15, 8)
 #define CDNS_PCIE_NORMAL_MSG_CODE(code) \
 	(((code) << 8) & CDNS_PCIE_NORMAL_MSG_CODE_MASK)
-#define CDNS_PCIE_MSG_NO_DATA			BIT(16)
+#define CDNS_PCIE_MSG_DATA			BIT(16)
 
 struct cdns_pcie;
 
-- 
2.39.5