[d-kernel] [PATCH 32/39] dw-pcie: refuse to load on Baikal-M with recent firmware

[Daniil Gnusarev]

From: Alexey Sheplyakov <asheplyakov на basealt.ru>

Firmware from SDK-M 5.4 is incompatible with dw-pcie driver.
Yet the DTB (passed to kernel by the firmware) claims otherwise.
Hence refuse to load if device node is compatilbe with
`baikal,bm1000-pcie` (earlier versions of Baikal-M firmware used
a different compatible string).

Signed-off-by: Alexey Sheplyakov <asheplyakov на basealt.ru>
X-feature-Baikal-M
X-DONTUPSTREAM
---
 drivers/pci/controller/dwc/Makefile               | 8 ++++----
 drivers/pci/controller/dwc/pcie-designware-plat.c | 5 +++++
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile
index 4e213d43a517c..3b1cd5ab98dee 100644
--- a/drivers/pci/controller/dwc/Makefile
+++ b/drivers/pci/controller/dwc/Makefile
@@ -1,9 +1,12 @@
 # SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_PCIE_BAIKAL) += pcie-baikal.o
+pcie-baikal-objs := pcie-baikal-core.o \
+                    pcie-baikal-tune.o
+
 obj-$(CONFIG_PCIE_DW) += pcie-designware.o
 obj-$(CONFIG_PCIE_DW_HOST) += pcie-designware-host.o
 obj-$(CONFIG_PCIE_DW_EP) += pcie-designware-ep.o
 obj-$(CONFIG_PCIE_DW_PLAT) += pcie-designware-plat.o
-obj-$(CONFIG_PCIE_BAIKAL) += pcie-baikal.o
 obj-$(CONFIG_PCIE_BT1) += pcie-bt1.o
 obj-$(CONFIG_PCI_DRA7XX) += pci-dra7xx.o
 obj-$(CONFIG_PCI_EXYNOS) += pci-exynos.o
@@ -28,9 +31,6 @@ obj-$(CONFIG_PCIE_UNIPHIER) += pcie-uniphier.o
 obj-$(CONFIG_PCIE_UNIPHIER_EP) += pcie-uniphier-ep.o
 obj-$(CONFIG_PCIE_VISCONTI_HOST) += pcie-visconti.o
 
-pcie-baikal-objs := pcie-baikal-core.o \
-                    pcie-baikal-tune.o
-
 # The following drivers are for devices that use the generic ACPI
 # pci_root.c driver but don't support standard ECAM config access.
 # They contain MCFG quirks to replace the generic ECAM accessors with
diff --git a/drivers/pci/controller/dwc/pcie-designware-plat.c b/drivers/pci/controller/dwc/pcie-designware-plat.c
index b625841e98aa0..96d01ebd16137 100644
--- a/drivers/pci/controller/dwc/pcie-designware-plat.c
+++ b/drivers/pci/controller/dwc/pcie-designware-plat.c
@@ -112,6 +112,11 @@ static int dw_plat_pcie_probe(struct platform_device *pdev)
 	const struct dw_plat_pcie_of_data *data;
 	enum dw_pcie_device_mode mode;
 
+	if (of_device_is_compatible(dev->of_node, "baikal,bm1000-pcie")) {
+		dev_err(dev, "refusing to load on Baikal-M with SDK-M 5.{4,5}\n");
+		return -ENODEV;
+	}
+
 	data = of_device_get_match_data(dev);
 	if (!data)
 		return -EINVAL;
-- 
2.42.2