[PATCH v13 3/5] PCI: j721e: Add per platform maximum lane settings

From: Siddharth Vadapalli
Date: Tue Nov 28 2023 - 00:44:48 EST


From: Matt Ranostay <mranostay@xxxxxx>

Various platforms have different maximum amount of lanes that can be
selected. Add max_lanes to struct j721e_pcie to allow for detection of this
which is needed to calculate the needed bitmask size for the possible lane
count.

Signed-off-by: Matt Ranostay <mranostay@xxxxxx>
Signed-off-by: Achal Verma <a-verma1@xxxxxx>
Signed-off-by: Siddharth Vadapalli <s-vadapalli@xxxxxx>
---
drivers/pci/controller/cadence/pci-j721e.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c
index 2c87e7728a65..63c758b14314 100644
--- a/drivers/pci/controller/cadence/pci-j721e.c
+++ b/drivers/pci/controller/cadence/pci-j721e.c
@@ -47,8 +47,6 @@ enum link_status {

#define GENERATION_SEL_MASK GENMASK(1, 0)

-#define MAX_LANES 2
-
struct j721e_pcie {
struct cdns_pcie *cdns_pcie;
struct clk *refclk;
@@ -71,6 +69,7 @@ struct j721e_pcie_data {
unsigned int quirk_disable_flr:1;
u32 linkdown_irq_regfield;
unsigned int byte_access_allowed:1;
+ unsigned int max_lanes;
};

static inline u32 j721e_pcie_user_readl(struct j721e_pcie *pcie, u32 offset)
@@ -290,11 +289,13 @@ static const struct j721e_pcie_data j721e_pcie_rc_data = {
.quirk_retrain_flag = true,
.byte_access_allowed = false,
.linkdown_irq_regfield = LINK_DOWN,
+ .max_lanes = 2,
};

static const struct j721e_pcie_data j721e_pcie_ep_data = {
.mode = PCI_MODE_EP,
.linkdown_irq_regfield = LINK_DOWN,
+ .max_lanes = 2,
};

static const struct j721e_pcie_data j7200_pcie_rc_data = {
@@ -302,23 +303,27 @@ static const struct j721e_pcie_data j7200_pcie_rc_data = {
.quirk_detect_quiet_flag = true,
.linkdown_irq_regfield = J7200_LINK_DOWN,
.byte_access_allowed = true,
+ .max_lanes = 2,
};

static const struct j721e_pcie_data j7200_pcie_ep_data = {
.mode = PCI_MODE_EP,
.quirk_detect_quiet_flag = true,
.quirk_disable_flr = true,
+ .max_lanes = 2,
};

static const struct j721e_pcie_data am64_pcie_rc_data = {
.mode = PCI_MODE_RC,
.linkdown_irq_regfield = J7200_LINK_DOWN,
.byte_access_allowed = true,
+ .max_lanes = 1,
};

static const struct j721e_pcie_data am64_pcie_ep_data = {
.mode = PCI_MODE_EP,
.linkdown_irq_regfield = J7200_LINK_DOWN,
+ .max_lanes = 1,
};

static const struct of_device_id of_j721e_pcie_match[] = {
@@ -432,8 +437,10 @@ static int j721e_pcie_probe(struct platform_device *pdev)
pcie->user_cfg_base = base;

ret = of_property_read_u32(node, "num-lanes", &num_lanes);
- if (ret || num_lanes > MAX_LANES)
+ if (ret || num_lanes > data->max_lanes) {
+ dev_warn(dev, "num-lanes property not provided or invalid, setting num-lanes to 1\n");
num_lanes = 1;
+ }
pcie->num_lanes = num_lanes;

if (dma_set_mask_and_coherent(dev, DMA_BIT_MASK(48)))
--
2.34.1