ARM: mach-shmobile: sh73a0: Minimal setup using DT

Allow a minimal setup of the sh73a0 SoC using a flattened device tree.
In particular, Configure the i2c controllers using a flattened device tree.

SCI serial controller and CMT clock source, whose drivers do not yet
support configuration using a flattened device tree, are still configured
using C code in order to allow booting of a board with this SoC.

*** Please note that the clock initialisation scheme used in
    this patch does not currently work with SMP as there
    is a yet to be resolved lock-up in workqueue initialisation.

    CONFIG_SMP must be disabled when using this code. ***

Includes update from Thierry Reding to no longer use gic_handle_irq()

Cc: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

fix

arch/arm/boot/dts/sh73a0.dtsi

@@ -30,4 +30,64 @@ gic: interrupt-controller@f0001000 {
 		reg = <0xf0001000 0x1000>,
 		      <0xf0000100 0x100>;
 	};
+
+	i2c0: i2c@0xe6820000 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		compatible = "renesas,rmobile-iic";
+		reg = <0xe6820000 0x425>;
+		interrupt-parent = <&gic>;
+		interrupts = <0 167 0x4
+			      0 168 0x4
+			      0 169 0x4
+			      0 170 0x4>;
+	};
+
+	i2c1: i2c@0xe6822000 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		compatible = "renesas,rmobile-iic";
+		reg = <0xe6822000 0x425>;
+		interrupt-parent = <&gic>;
+		interrupts = <0 51 0x4
+			      0 52 0x4
+			      0 53 0x4
+			      0 54 0x4>;
+	};
+
+	i2c2: i2c@0xe6824000 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		compatible = "renesas,rmobile-iic";
+		reg = <0xe6824000 0x425>;
+		interrupt-parent = <&gic>;
+		interrupts = <0 171 0x4
+			      0 172 0x4
+			      0 173 0x4
+			      0 174 0x4>;
+	};
+
+	i2c3: i2c@0xe6826000 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		compatible = "renesas,rmobile-iic";
+		reg = <0xe6826000 0x425>;
+		interrupt-parent = <&gic>;
+		interrupts = <0 183 0x4
+			      0 184 0x4
+			      0 185 0x4
+			      0 186 0x4>;
+	};
+
+	i2c4: i2c@0xe6828000 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		compatible = "renesas,rmobile-iic";
+		reg = <0xe6828000 0x425>;
+		interrupt-parent = <&gic>;
+		interrupts = <0 187 0x4
+			      0 188 0x4
+			      0 189 0x4
+			      0 190 0x4>;
+	};
 };

arch/arm/mach-shmobile/clock-sh73a0.c

@@ -525,6 +525,13 @@ static struct clk mstp_clks[MSTP_NR] = {
 	[MSTP403] = MSTP(&r_clk, SMSTPCR4, 3, 0), /* KEYSC */
 };
 
+/* The lookups structure below includes duplicate entries for some clocks
+ * with alternate names.
+ * - The traditional name used when a device is initialised with platform data
+ * - The name used when a device is initialised using device tree
+ * The longer-term aim is to remove these duplicates, and indeed the
+ * lookups table entirely, by describing clocks using device tree.
+ */
 static struct clk_lookup lookups[] = {
 	/* main clocks */
 	CLKDEV_CON_ID("r_clk", &r_clk),
@@ -545,6 +552,7 @@ static struct clk_lookup lookups[] = {
 
 	/* MSTP32 clocks */
 	CLKDEV_DEV_ID("i2c-sh_mobile.2", &mstp_clks[MSTP001]), /* I2C2 */
+	CLKDEV_DEV_ID("e6824000.i2c", &mstp_clks[MSTP001]), /* I2C2 */
 	CLKDEV_DEV_ID("sh_mobile_ceu.1", &mstp_clks[MSTP129]), /* CEU1 */
 	CLKDEV_DEV_ID("sh-mobile-csi2.1", &mstp_clks[MSTP128]), /* CSI2-RX1 */
 	CLKDEV_DEV_ID("sh_mobile_ceu.0", &mstp_clks[MSTP127]), /* CEU0 */
@@ -553,6 +561,7 @@ static struct clk_lookup lookups[] = {
 	CLKDEV_DEV_ID("sh_tmu.1", &mstp_clks[MSTP125]), /* TMU01 */
 	CLKDEV_DEV_ID("sh-mipi-dsi.0", &mstp_clks[MSTP118]), /* DSITX */
 	CLKDEV_DEV_ID("i2c-sh_mobile.0", &mstp_clks[MSTP116]), /* I2C0 */
+	CLKDEV_DEV_ID("e6820000.i2c", &mstp_clks[MSTP116]), /* I2C0 */
 	CLKDEV_DEV_ID("sh_mobile_lcdc_fb.0", &mstp_clks[MSTP100]), /* LCDC0 */
 	CLKDEV_DEV_ID("sh-sci.7", &mstp_clks[MSTP219]), /* SCIFA7 */
 	CLKDEV_DEV_ID("sh-dma-engine.0", &mstp_clks[MSTP218]), /* SY-DMAC */
@@ -569,6 +578,7 @@ static struct clk_lookup lookups[] = {
 	CLKDEV_DEV_ID("sh_fsi2", &mstp_clks[MSTP328]), /* FSI */
 	CLKDEV_DEV_ID("sh_irda.0", &mstp_clks[MSTP325]), /* IrDA */
 	CLKDEV_DEV_ID("i2c-sh_mobile.1", &mstp_clks[MSTP323]), /* I2C1 */
+	CLKDEV_DEV_ID("e6822000.i2c", &mstp_clks[MSTP323]), /* I2C1 */
 	CLKDEV_DEV_ID("renesas_usbhs", &mstp_clks[MSTP322]), /* USB */
 	CLKDEV_DEV_ID("sh_mobile_sdhi.0", &mstp_clks[MSTP314]), /* SDHI0 */
 	CLKDEV_DEV_ID("sh_mobile_sdhi.1", &mstp_clks[MSTP313]), /* SDHI1 */
@@ -579,7 +589,9 @@ static struct clk_lookup lookups[] = {
 	CLKDEV_DEV_ID("leds-renesas-tpu.30", &mstp_clks[MSTP301]), /* TPU3 */
 	CLKDEV_DEV_ID("leds-renesas-tpu.41", &mstp_clks[MSTP300]), /* TPU4 */
 	CLKDEV_DEV_ID("i2c-sh_mobile.3", &mstp_clks[MSTP411]), /* I2C3 */
+	CLKDEV_DEV_ID("e6826000.i2c", &mstp_clks[MSTP411]), /* I2C3 */
 	CLKDEV_DEV_ID("i2c-sh_mobile.4", &mstp_clks[MSTP410]), /* I2C4 */
+	CLKDEV_DEV_ID("e6828000.i2c", &mstp_clks[MSTP410]), /* I2C4 */
 	CLKDEV_DEV_ID("sh_keysc.0", &mstp_clks[MSTP403]), /* KEYSC */
 };
 

arch/arm/mach-shmobile/include/mach/common.h

@@ -38,7 +38,9 @@ extern void sh73a0_init_irq_dt(void);
 extern void sh73a0_map_io(void);
 extern void sh73a0_earlytimer_init(void);
 extern void sh73a0_add_early_devices(void);
+extern void sh73a0_add_early_devices_dt(void);
 extern void sh73a0_add_standard_devices(void);
+extern void sh73a0_add_standard_devices_dt(void);
 extern void sh73a0_clock_init(void);
 extern void sh73a0_pinmux_init(void);
 extern void sh73a0_pm_init(void);

arch/arm/mach-shmobile/setup-sh73a0.c

@@ -23,6 +23,7 @@
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/platform_device.h>
+#include <linux/of_platform.h>
 #include <linux/delay.h>
 #include <linux/input.h>
 #include <linux/io.h>
@@ -754,7 +755,7 @@ static struct platform_device pmu_device = {
 	.resource	= pmu_resources,
 };
 
-static struct platform_device *sh73a0_early_devices[] __initdata = {
+static struct platform_device *sh73a0_early_devices_dt[] __initdata = {
 	&scif0_device,
 	&scif1_device,
 	&scif2_device,
@@ -765,6 +766,9 @@ static struct platform_device *sh73a0_early_devices[] __initdata = {
 	&scif7_device,
 	&scif8_device,
 	&cmt10_device,
+};
+
+static struct platform_device *sh73a0_early_devices[] __initdata = {
 	&tmu00_device,
 	&tmu01_device,
 };
@@ -787,6 +791,8 @@ void __init sh73a0_add_standard_devices(void)
 	/* Clear software reset bit on SY-DMAC module */
 	__raw_writel(__raw_readl(SRCR2) & ~(1 << 18), SRCR2);
 
+	platform_add_devices(sh73a0_early_devices_dt,
+			    ARRAY_SIZE(sh73a0_early_devices_dt));
 	platform_add_devices(sh73a0_early_devices,
 			    ARRAY_SIZE(sh73a0_early_devices));
 	platform_add_devices(sh73a0_late_devices,
@@ -805,9 +811,63 @@ void __init sh73a0_earlytimer_init(void)
 
 void __init sh73a0_add_early_devices(void)
 {
+	early_platform_add_devices(sh73a0_early_devices_dt,
+				   ARRAY_SIZE(sh73a0_early_devices_dt));
 	early_platform_add_devices(sh73a0_early_devices,
 				   ARRAY_SIZE(sh73a0_early_devices));
 
 	/* setup early console here as well */
 	shmobile_setup_console();
 }
+
+#ifdef CONFIG_USE_OF
+
+/* Please note that the clock initialisation shcheme used in
+ * sh73a0_add_early_devices_dt() and sh73a0_add_standard_devices_dt()
+ * does not work with SMP as there is a yet to be resolved lock-up in
+ * workqueue initialisation.
+ *
+ * CONFIG_SMP should be disabled when using this code.
+ */
+
+void __init sh73a0_add_early_devices_dt(void)
+{
+	shmobile_setup_delay(1196, 44, 46); /* Cortex-A9 @ 1196MHz */
+
+	early_platform_add_devices(sh73a0_early_devices_dt,
+				   ARRAY_SIZE(sh73a0_early_devices_dt));
+
+	/* setup early console here as well */
+	shmobile_setup_console();
+}
+
+static const struct of_dev_auxdata sh73a0_auxdata_lookup[] __initconst = {
+	{},
+};
+
+void __init sh73a0_add_standard_devices_dt(void)
+{
+	/* clocks are setup late during boot in the case of DT */
+	sh73a0_clock_init();
+
+	platform_add_devices(sh73a0_early_devices_dt,
+			     ARRAY_SIZE(sh73a0_early_devices_dt));
+	of_platform_populate(NULL, of_default_bus_match_table,
+			     sh73a0_auxdata_lookup, NULL);
+}
+
+static const char *sh73a0_boards_compat_dt[] __initdata = {
+	"renesas,sh73a0",
+	NULL,
+};
+
+DT_MACHINE_START(SH73A0_DT, "Generic SH73A0 (Flattened Device Tree)")
+	.map_io		= sh73a0_map_io,
+	.init_early	= sh73a0_add_early_devices_dt,
+	.nr_irqs	= NR_IRQS_LEGACY,
+	.init_irq	= sh73a0_init_irq_dt,
+	.init_machine	= sh73a0_add_standard_devices_dt,
+	.init_time	= shmobile_timer_init,
+	.dt_compat	= sh73a0_boards_compat_dt,
+MACHINE_END
+#endif /* CONFIG_USE_OF */