[PATCH v3 1/3] PCI: j721e: Add PCIe 4x lane selection support

Matt Ranostay mranostay at ti.com
Wed Oct 19 18:29:09 PDT 2022


Add support for setting of two-bit field that allows selection of 4x
lane PCIe which was previously limited to only 2x lanes.

Signed-off-by: Matt Ranostay <mranostay at ti.com>
---
 drivers/pci/controller/cadence/pci-j721e.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c
index a82f845cc4b5..d9b1527421c3 100644
--- a/drivers/pci/controller/cadence/pci-j721e.c
+++ b/drivers/pci/controller/cadence/pci-j721e.c
@@ -43,7 +43,6 @@ enum link_status {
 };
 
 #define J721E_MODE_RC			BIT(7)
-#define LANE_COUNT_MASK			BIT(8)
 #define LANE_COUNT(n)			((n) << 8)
 
 #define GENERATION_SEL_MASK		GENMASK(1, 0)
@@ -207,11 +206,15 @@ static int j721e_pcie_set_lane_count(struct j721e_pcie *pcie,
 {
 	struct device *dev = pcie->cdns_pcie->dev;
 	u32 lanes = pcie->num_lanes;
+	u32 mask = GENMASK(8, 8);
 	u32 val = 0;
 	int ret;
 
+	if (lanes == 4)
+		mask = GENMASK(9, 8);
+
 	val = LANE_COUNT(lanes - 1);
-	ret = regmap_update_bits(syscon, offset, LANE_COUNT_MASK, val);
+	ret = regmap_update_bits(syscon, offset, mask, val);
 	if (ret)
 		dev_err(dev, "failed to set link count\n");
 
-- 
2.38.GIT




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