[PATCH v4 3/3] PCI: xilinx-nwl: Increase ECAM size to accommodate 256 buses

From: Thippeswamy Havalige
Date: Mon Aug 14 2023 - 13:16:02 EST


Our controller is expecting ECAM size to be programmed by software. By
programming "NWL_ECAM_VALUE_DEFAULT 12" controller can access up to 16MB
ECAM region which is used to detect 16 buses, so by updating
"NWL_ECAM_VALUE_DEFAULT" to 16 so that controller can access up to 256MB
ECAM region to detect 256 buses.

Nothing will break, when having a DT with the smaller ECAM size and boot a
kernel that includes this change,but the kernel will only be able to use 16
buses.

Signed-off-by: Thippeswamy Havalige <thippeswamy.havalige@xxxxxxx>
---
Changes in v4:
Move modified ECAM max size macro into a seperate patch.
drivers/pci/controller/pcie-xilinx-nwl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/controller/pcie-xilinx-nwl.c b/drivers/pci/controller/pcie-xilinx-nwl.c
index 8fe0e8a325b0..e307aceba5c9 100644
--- a/drivers/pci/controller/pcie-xilinx-nwl.c
+++ b/drivers/pci/controller/pcie-xilinx-nwl.c
@@ -126,7 +126,7 @@
#define E_ECAM_CR_ENABLE BIT(0)
#define E_ECAM_SIZE_LOC GENMASK(20, 16)
#define E_ECAM_SIZE_SHIFT 16
-#define NWL_ECAM_MAX_SIZE 12
+#define NWL_ECAM_MAX_SIZE 16

#define CFG_DMA_REG_BAR GENMASK(2, 0)
#define CFG_PCIE_CACHE GENMASK(7, 0)
--
2.17.1