pci: Add support for Qualcomm PCIe controller

Add support for the PCIe busses on Qualcomm platforms,
by using the pcie_dw_common infrastructure.

The driver is based on the Linux driver but only supporting
the "1_9_0" and compatible platforms like:
- sa8540p
- sc7280
- sc8180x
- sc8280xp
- sdm845
- sdx55
- sm8150
- sm8250
- sm8350
- sm8450
- sm8550
- sm8650
- x1e80100

But it has only been tested on:
- sc7280
- sm8550
- sm8650
- x1e80100

It supports setting the IOMMU SID table for supported platforms.

Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20241125-topic-pcie-controller-v1-2-45c20070dd53@linaro.org
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index 4190143..4f876d3 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -371,6 +371,14 @@
 	  Say Y here if you want to enable DW PCIe controller support on
 	  Amlogic SoCs.
 
+config PCIE_DW_QCOM
+	bool "Qualcomm DesignWare based PCIe controller"
+	depends on ARCH_SNAPDRAGON
+	select PCIE_DW_COMMON
+	help
+	  Say Y here if you want to enable DW PCIe controller support on
+	  Qualcomm SoCs.
+
 config PCIE_ROCKCHIP
 	bool "Enable Rockchip PCIe driver"
 	depends on ARCH_ROCKCHIP