[PATCH 2/2] pci: host: pci-dra7xx: Enable x2 mode support

From: Kishon Vijay Abraham I
Date: Wed Jan 06 2016 - 05:51:08 EST


Perform syscon configurations to get x2 mode to working in DRA74x and
DRA72x. Also add a new compatible string to dfferentiate
DRA72x and DRA74x, since b1c0 mask is different for both these platforms.

Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
---
Documentation/devicetree/bindings/pci/ti-pci.txt | 8 ++-
drivers/pci/host/pci-dra7xx.c | 81 +++++++++++++++++++++-
2 files changed, 86 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/pci/ti-pci.txt b/Documentation/devicetree/bindings/pci/ti-pci.txt
index 60e2516..0b10e84 100644
--- a/Documentation/devicetree/bindings/pci/ti-pci.txt
+++ b/Documentation/devicetree/bindings/pci/ti-pci.txt
@@ -1,7 +1,9 @@
TI PCI Controllers

PCIe Designware Controller
- - compatible: Should be "ti,dra7-pcie""
+ - compatible: "ti,dra7-pcie" is deprecated
+ Should be "ti,dra746-pcie" for DRA74x
+ Should be "ti,dra726-pcie" for DRA72x
- reg : Two register ranges as listed in the reg-names property
- reg-names : The first entry must be "ti-conf" for the TI specific registers
The second entry must be "rc-dbics" for the designware pcie
@@ -14,6 +16,10 @@ PCIe Designware Controller
where <X> is the instance number of the pcie from the HW spec.
- interrupts : Two interrupt entries must be specified. The first one is for
main interrupt line and the second for MSI interrupt line.
+ - syscon-lane-conf : phandle/offset pair. Phandle to the system control module and the
+ register offset to specify 1 lane or 2 lane.
+ - syscon-lane-sel : phandle/offset pair. Phandle to the system control module and the
+ register offset to specify lane selection.
- #address-cells,
#size-cells,
#interrupt-cells,
diff --git a/drivers/pci/host/pci-dra7xx.c b/drivers/pci/host/pci-dra7xx.c
index 05bbeee..dac216f 100644
--- a/drivers/pci/host/pci-dra7xx.c
+++ b/drivers/pci/host/pci-dra7xx.c
@@ -22,9 +22,11 @@
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
+#include <linux/of_platform.h>
#include <linux/resource.h>
#include <linux/types.h>
-#include <linux/platform_data/pci-dra7xx.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>

#include <linux/platform_data/pci-dra7xx.h>

@@ -67,14 +69,22 @@
#define LINK_UP BIT(16)
#define DRA7XX_CPU_TO_BUS_ADDR 0x0FFFFFFF

+#define PCIE_1LANE_2LANE_SELECTION BIT(13)
+#define PCIE_B1C0_MODE_SEL BIT(2)
+
struct dra7xx_pcie {
void __iomem *base;
+ u32 *b1c0_mask;
struct phy **phy;
int lanes;
struct device *dev;
struct pcie_port pp;
};

+struct dra7xx_pcie_data {
+ u32 b1co_mode_sel_mask;
+};
+
#define to_dra7xx_pcie(x) container_of((x), struct dra7xx_pcie, pp)

static inline u32 dra7xx_pcie_readl(struct dra7xx_pcie *pcie, u32 offset)
@@ -358,6 +368,57 @@ static int dra7xx_pcie_reset(struct platform_device *pdev)
return 0;
}

+static const struct of_device_id of_dra7xx_pcie_match[];
+
+static int dra7xx_pcie_configure_two_lane(struct device *dev)
+{
+ struct device_node *np = dev->of_node;
+ struct regmap *pcie_syscon;
+ unsigned int pcie_reg;
+ struct dra7xx_pcie_data *data;
+ const struct of_device_id *match;
+
+ match = of_match_device(of_dra7xx_pcie_match, dev);
+ if (!match)
+ return -EINVAL;
+
+ data = (struct dra7xx_pcie_data *)match->data;
+ if (!data) {
+ dev_err(dev, "no b1c0 mask data\n");
+ return -EINVAL;
+ }
+
+ pcie_syscon = syscon_regmap_lookup_by_phandle(np, "syscon-lane-conf");
+ if (IS_ERR(pcie_syscon)) {
+ dev_err(dev, "unable to get syscon-lane-conf\n");
+ return -EINVAL;
+ }
+
+ if (of_property_read_u32_index(np, "syscon-lane-conf", 1, &pcie_reg)) {
+ dev_err(dev, "couldn't get lane configuration reg offset\n");
+ return -EINVAL;
+ }
+
+ regmap_update_bits(pcie_syscon, pcie_reg, PCIE_1LANE_2LANE_SELECTION,
+ PCIE_1LANE_2LANE_SELECTION);
+
+ pcie_syscon = syscon_regmap_lookup_by_phandle(np, "syscon-lane-sel");
+ if (IS_ERR(pcie_syscon)) {
+ dev_err(dev, "unable to get syscon-lane-sel\n");
+ return -EINVAL;
+ }
+
+ if (of_property_read_u32_index(np, "syscon-lane-sel", 1, &pcie_reg)) {
+ dev_err(dev, "couldn't get lane selection reg offset\n");
+ return -EINVAL;
+ }
+
+ regmap_update_bits(pcie_syscon, pcie_reg, data->b1co_mode_sel_mask,
+ PCIE_B1C0_MODE_SEL);
+
+ return 0;
+}
+
static int __init dra7xx_pcie_probe(struct platform_device *pdev)
{
u32 reg;
@@ -428,6 +489,12 @@ static int __init dra7xx_pcie_probe(struct platform_device *pdev)
}
}

+ if (lanes == 2) {
+ ret = dra7xx_pcie_configure_two_lane(dev);
+ if (ret < 0)
+ goto err_phy;
+ }
+
dra7xx->base = base;
dra7xx->phy = phy;
dra7xx->dev = dev;
@@ -581,8 +648,18 @@ static const struct dev_pm_ops dra7xx_pcie_pm_ops = {
dra7xx_pcie_resume_noirq)
};

+static const struct dra7xx_pcie_data dra746_pcie_data = {
+ .b1co_mode_sel_mask = BIT(2),
+};
+
+static const struct dra7xx_pcie_data dra726_pcie_data = {
+ .b1co_mode_sel_mask = GENMASK(3, 2),
+};
+
static const struct of_device_id of_dra7xx_pcie_match[] = {
- { .compatible = "ti,dra7-pcie", },
+ { .compatible = "ti,dra7-pcie", .data = &dra746_pcie_data },
+ { .compatible = "ti,dra746-pcie", .data = &dra746_pcie_data },
+ { .compatible = "ti,dra726-pcie", .data = &dra726_pcie_data },
{},
};
MODULE_DEVICE_TABLE(of, of_dra7xx_pcie_match);
--
1.7.9.5

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