[PATCH v5 04/12] PCI: brcmstb: Use bridge reset if available

[Jim Quinlan <james.quinlan@xxxxxxxxxxxx>]

The 7712 SOC has a bridge reset which can be described in the device tree.
Use it if present.  Otherwise, continue to use the legacy method to reset
the bridge.

Signed-off-by: Jim Quinlan <james.quinlan@xxxxxxxxxxxx>
---
 drivers/pci/controller/pcie-brcmstb.c | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index 7595e7009192..4d68fe318178 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -265,6 +265,7 @@ struct brcm_pcie {
 	enum pcie_type		type;
 	struct reset_control	*rescal;
 	struct reset_control	*perst_reset;
+	struct reset_control	*bridge_reset;
 	int			num_memc;
 	u64			memc_size[PCIE_BRCM_MAX_MEMC];
 	u32			hw_rev;
@@ -732,12 +733,19 @@ static void __iomem *brcm7425_pcie_map_bus(struct pci_bus *bus,
 
 static void brcm_pcie_bridge_sw_init_set_generic(struct brcm_pcie *pcie, u32 val)
 {
-	u32 tmp, mask =  RGR1_SW_INIT_1_INIT_GENERIC_MASK;
-	u32 shift = RGR1_SW_INIT_1_INIT_GENERIC_SHIFT;
+	if (val)
+		reset_control_assert(pcie->bridge_reset);
+	else
+		reset_control_deassert(pcie->bridge_reset);
 
-	tmp = readl(pcie->base + PCIE_RGR1_SW_INIT_1(pcie));
-	tmp = (tmp & ~mask) | ((val << shift) & mask);
-	writel(tmp, pcie->base + PCIE_RGR1_SW_INIT_1(pcie));
+	if (!pcie->bridge_reset) {
+		u32 tmp, mask =  RGR1_SW_INIT_1_INIT_GENERIC_MASK;
+		u32 shift = RGR1_SW_INIT_1_INIT_GENERIC_SHIFT;
+
+		tmp = readl(pcie->base + PCIE_RGR1_SW_INIT_1(pcie));
+		tmp = (tmp & ~mask) | ((val << shift) & mask);
+		writel(tmp, pcie->base + PCIE_RGR1_SW_INIT_1(pcie));
+	}
 }
 
 static void brcm_pcie_bridge_sw_init_set_7278(struct brcm_pcie *pcie, u32 val)
@@ -1621,10 +1629,16 @@ static int brcm_pcie_probe(struct platform_device *pdev)
 	if (IS_ERR(pcie->perst_reset))
 		return PTR_ERR(pcie->perst_reset);
 
+	pcie->bridge_reset = devm_reset_control_get_optional_exclusive(&pdev->dev, "bridge");
+	if (IS_ERR(pcie->bridge_reset))
+		return PTR_ERR(pcie->bridge_reset);
+
 	ret = clk_prepare_enable(pcie->clk);
 	if (ret)
 		return dev_err_probe(&pdev->dev, ret, "could not enable clock\n");
 
+	pcie->bridge_sw_init_set(pcie, 0);
+
 	ret = reset_control_reset(pcie->rescal);
 	if (dev_err_probe(&pdev->dev, ret, "failed to deassert 'rescal'\n"))
 		goto clk_disable_unprepare;
-- 
2.17.1