[PATCH v2 07/15] MIPS: lantiq: Convert the xbar driver to a platform_driver

Hauke Mehrtens hauke at hauke-m.de
Sun May 21 06:09:10 PDT 2017


From: Martin Blumenstingl <martin.blumenstingl at googlemail.com>

This allows using the xbar driver on ARX300 based SoCs which require the
same xbar setup as the xRX200 chipsets because the xbar driver
initialization is not guarded by an xRX200 specific
of_machine_is_compatible condition anymore. Additionally the new driver
takes a syscon phandle to configure the XBAR endianness bits in RCU
(before this was done in arch/mips/lantiq/xway/reset.c and also
guarded by an VRX200 specific if-statement).

Signed-off-by: Hauke Mehrtens <hauke at hauke-m.de>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl at googlemail.com>
---
 .../devicetree/bindings/mips/lantiq/xbar.txt       |  24 +++++
 MAINTAINERS                                        |   1 +
 arch/mips/lantiq/xway/reset.c                      |   4 -
 arch/mips/lantiq/xway/sysctrl.c                    |  41 ---------
 drivers/soc/Makefile                               |   1 +
 drivers/soc/lantiq/Makefile                        |   1 +
 drivers/soc/lantiq/xbar.c                          | 101 +++++++++++++++++++++
 7 files changed, 128 insertions(+), 45 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/mips/lantiq/xbar.txt
 create mode 100644 drivers/soc/lantiq/Makefile
 create mode 100644 drivers/soc/lantiq/xbar.c

diff --git a/Documentation/devicetree/bindings/mips/lantiq/xbar.txt b/Documentation/devicetree/bindings/mips/lantiq/xbar.txt
new file mode 100644
index 000000000000..7e1ea5299744
--- /dev/null
+++ b/Documentation/devicetree/bindings/mips/lantiq/xbar.txt
@@ -0,0 +1,24 @@
+Lantiq XWAY SoC XBAR binding
+============================
+
+
+-------------------------------------------------------------------------------
+Required properties:
+- compatible	: Should be one of
+				"lantiq,xbar-xway"
+				"lantiq,xbar-xrx200"
+- reg		: The address and length of the XBAR registers
+
+Optional properties:
+- lantiq,rcu-syscon	: A phandle and offset to the endianness configuration
+			  registers in the RCU module
+
+
+-------------------------------------------------------------------------------
+Example for the XBAR on the xRX200 SoCs:
+	xbar0: xbar at 400000 {
+		compatible = "lantiq,xbar-xway";
+		reg = <0x400000 0x1000>;
+		big-endian;
+		lantiq,rcu-syscon = <&rcu0 0x4c>;
+	};
diff --git a/MAINTAINERS b/MAINTAINERS
index f7d568b8f133..11c33f7d63ba 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7434,6 +7434,7 @@ M:	John Crispin <john at phrozen.org>
 L:	linux-mips at linux-mips.org
 S:	Maintained
 F:	arch/mips/lantiq
+F:	drivers/soc/lantiq
 
 LAPB module
 L:	linux-x25 at vger.kernel.org
diff --git a/arch/mips/lantiq/xway/reset.c b/arch/mips/lantiq/xway/reset.c
index 83fd65d76e81..b6752c95a600 100644
--- a/arch/mips/lantiq/xway/reset.c
+++ b/arch/mips/lantiq/xway/reset.c
@@ -373,10 +373,6 @@ static int __init mips_reboot_setup(void)
 	    of_machine_is_compatible("lantiq,vr9"))
 		ltq_usb_init();
 
-	if (of_machine_is_compatible("lantiq,vr9"))
-		ltq_rcu_w32(ltq_rcu_r32(RCU_AHB_ENDIAN) | RCU_VR9_BE_AHB1S,
-			    RCU_AHB_ENDIAN);
-
 	_machine_restart = ltq_machine_restart;
 	_machine_halt = ltq_machine_halt;
 	pm_power_off = ltq_machine_power_off;
diff --git a/arch/mips/lantiq/xway/sysctrl.c b/arch/mips/lantiq/xway/sysctrl.c
index 95bec460b651..706639a343bc 100644
--- a/arch/mips/lantiq/xway/sysctrl.c
+++ b/arch/mips/lantiq/xway/sysctrl.c
@@ -145,15 +145,7 @@ static u32 pmu_clk_cr_b[] = {
 #define pmu_w32(x, y)	ltq_w32((x), pmu_membase + (y))
 #define pmu_r32(x)	ltq_r32(pmu_membase + (x))
 
-#define XBAR_ALWAYS_LAST	0x430
-#define XBAR_FPI_BURST_EN	BIT(1)
-#define XBAR_AHB_BURST_EN	BIT(2)
-
-#define xbar_w32(x, y)	ltq_w32((x), ltq_xbar_membase + (y))
-#define xbar_r32(x)	ltq_r32(ltq_xbar_membase + (x))
-
 static void __iomem *pmu_membase;
-static void __iomem *ltq_xbar_membase;
 void __iomem *ltq_cgu_membase;
 void __iomem *ltq_ebu_membase;
 
@@ -293,16 +285,6 @@ static void pci_ext_disable(struct clk *clk)
 	ltq_cgu_w32((1 << 31) | (1 << 30), pcicr);
 }
 
-static void xbar_fpi_burst_disable(void)
-{
-	u32 reg;
-
-	/* bit 1 as 1 --burst; bit 1 as 0 -- single */
-	reg = xbar_r32(XBAR_ALWAYS_LAST);
-	reg &= ~XBAR_FPI_BURST_EN;
-	xbar_w32(reg, XBAR_ALWAYS_LAST);
-}
-
 /* enable a clockout source */
 static int clkout_enable(struct clk *clk)
 {
@@ -459,26 +441,6 @@ void __init ltq_soc_init(void)
 	if (!pmu_membase || !ltq_cgu_membase || !ltq_ebu_membase)
 		panic("Failed to remap core resources");
 
-	if (of_machine_is_compatible("lantiq,vr9")) {
-		struct resource res_xbar;
-		struct device_node *np_xbar =
-				of_find_compatible_node(NULL, NULL,
-							"lantiq,xbar-xway");
-
-		if (!np_xbar)
-			panic("Failed to load xbar nodes from devicetree");
-		if (of_address_to_resource(np_xbar, 0, &res_xbar))
-			panic("Failed to get xbar resources");
-		if (!request_mem_region(res_xbar.start, resource_size(&res_xbar),
-			res_xbar.name))
-			panic("Failed to get xbar resources");
-
-		ltq_xbar_membase = ioremap_nocache(res_xbar.start,
-						   resource_size(&res_xbar));
-		if (!ltq_xbar_membase)
-			panic("Failed to remap xbar resources");
-	}
-
 	/* make sure to unprotect the memory region where flash is located */
 	ltq_ebu_w32(ltq_ebu_r32(LTQ_EBU_BUSCON0) & ~EBU_WRDIS, LTQ_EBU_BUSCON0);
 
@@ -605,7 +567,4 @@ void __init ltq_soc_init(void)
 		clkdev_add_pmu("1e116000.mei", "dfe", 1, 0, PMU_DFE);
 		clkdev_add_pmu("1e100400.serial", NULL, 1, 0, PMU_ASC0);
 	}
-
-	if (of_machine_is_compatible("lantiq,vr9"))
-		xbar_fpi_burst_disable();
 }
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index 824b44281efa..009b5de74a24 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_ARCH_DOVE)		+= dove/
 obj-$(CONFIG_MACH_DOVE)		+= dove/
 obj-y				+= fsl/
 obj-$(CONFIG_ARCH_MXC)		+= imx/
+obj-$(CONFIG_SOC_XWAY)		+= lantiq/
 obj-$(CONFIG_ARCH_MEDIATEK)	+= mediatek/
 obj-$(CONFIG_ARCH_QCOM)		+= qcom/
 obj-$(CONFIG_ARCH_RENESAS)	+= renesas/
diff --git a/drivers/soc/lantiq/Makefile b/drivers/soc/lantiq/Makefile
new file mode 100644
index 000000000000..7411bd23d58e
--- /dev/null
+++ b/drivers/soc/lantiq/Makefile
@@ -0,0 +1 @@
+obj-y				+= xbar.o
diff --git a/drivers/soc/lantiq/xbar.c b/drivers/soc/lantiq/xbar.c
new file mode 100644
index 000000000000..89590e189efc
--- /dev/null
+++ b/drivers/soc/lantiq/xbar.c
@@ -0,0 +1,101 @@
+/*
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under the terms of the GNU General Public License version 2 as published
+ *  by the Free Software Foundation.
+ *
+ *  Copyright (C) 2011-2015 John Crispin <blogic at openwrt.org>
+ *  Copyright (C) 2015 Martin Blumenstingl <martin.blumenstingl at googlemail.com>
+ */
+
+#include <linux/ioport.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/of_address.h>
+#include <linux/regmap.h>
+
+#include <lantiq_soc.h>
+
+#define XBAR_ALWAYS_LAST	0x430
+#define XBAR_FPI_BURST_EN	BIT(1)
+#define XBAR_AHB_BURST_EN	BIT(2)
+
+#define RCU_VR9_BE_AHB1S	0x00000008
+
+static int ltq_xbar_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct resource res_xbar;
+	struct regmap *rcu_regmap;
+	void __iomem *xbar_membase;
+	u32 rcu_ahb_endianness_reg_offset;
+	u32 rcu_ahb_endianness_val;
+	int ret;
+
+	ret = of_address_to_resource(np, 0, &res_xbar);
+	if (ret) {
+		dev_err(dev, "Failed to get xbar resources");
+		return ret;
+	}
+
+	if (!devm_request_mem_region(dev, res_xbar.start,
+				     resource_size(&res_xbar),
+		res_xbar.name)) {
+		dev_err(dev, "Failed to get xbar resources");
+		return -ENODEV;
+	}
+
+	xbar_membase = devm_ioremap_nocache(dev, res_xbar.start,
+						resource_size(&res_xbar));
+	if (!xbar_membase) {
+		dev_err(dev, "Failed to remap xbar resources");
+		return -ENODEV;
+	}
+
+	/* RCU configuration is optional */
+	rcu_regmap = syscon_regmap_lookup_by_phandle(np, "lantiq,rcu-syscon");
+	if (!IS_ERR_OR_NULL(rcu_regmap)) {
+		if (of_property_read_u32_index(np, "lantiq,rcu-syscon", 1,
+			&rcu_ahb_endianness_reg_offset)) {
+			dev_err(&pdev->dev, "Failed to get RCU reg offset\n");
+			return -EINVAL;
+		}
+
+		if (of_device_is_big_endian(np))
+			rcu_ahb_endianness_val = RCU_VR9_BE_AHB1S;
+		else
+			rcu_ahb_endianness_val = 0;
+
+		if (regmap_update_bits(rcu_regmap,
+					rcu_ahb_endianness_reg_offset,
+					RCU_VR9_BE_AHB1S,
+					rcu_ahb_endianness_val))
+			dev_warn(&pdev->dev,
+				"Failed to configure RCU AHB endianness\n");
+	}
+
+	/* disable fpi burst */
+	ltq_w32_mask(XBAR_FPI_BURST_EN, 0,
+		     xbar_membase + XBAR_ALWAYS_LAST);
+
+	return 0;
+}
+
+static const struct of_device_id xbar_match[] = {
+	{ .compatible = "lantiq,xbar-xway" },
+	{ .compatible = "lantiq,xbar-xrx200" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, xbar_match);
+
+static struct platform_driver xbar_driver = {
+	.probe = ltq_xbar_probe,
+	.driver = {
+		.name = "xbar-xway",
+		.of_match_table = xbar_match,
+	},
+};
+
+builtin_platform_driver(xbar_driver);
-- 
2.11.0




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