ARM: nomadik: initial devicetree support

Support basic device tree boot on the Nomadik. Implement the
support in the cpu file with the intent of deleting the board
files later. At this stage IRQ controllers, system timer,
l2x0 cache, UARTs and thus console boot is fully functional.
Patch out the code adding devices by initcalls for now so
as not to disturb the boot.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 77 insertions, 1 deletions

diff --git a/arch/arm/mach-nomadik/cpu-8815.c b/arch/arm/mach-nomadik/cpu-8815.c
index 351404673f6c..7c8e3487f4eb 100644
--- a/arch/arm/mach-nomadik/cpu-8815.c
+++ b/arch/arm/mach-nomadik/cpu-8815.c
@@ -25,13 +25,19 @@
 #include <linux/slab.h>
 #include <linux/irq.h>
 #include <linux/dma-mapping.h>
-#include <linux/irqchip/arm-vic.h>
+#include <linux/irqchip.h>
 #include <linux/platform_data/clk-nomadik.h>
 #include <linux/platform_data/pinctrl-nomadik.h>
+#include <linux/platform_data/clocksource-nomadik-mtu.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
 
 #include <mach/hardware.h>
 #include <mach/irqs.h>
+#include <asm/mach/arch.h>
 #include <asm/mach/map.h>
+#include <asm/mach/time.h>
 
 #include <asm/cacheflush.h>
 #include <asm/hardware/cache-l2x0.h>
@@ -160,3 +166,73 @@ void cpu8815_restart(char mode, const char *cmd)
 	/* Write anything to Reset status register */
 	writel(1, src_rstsr);
 }
+
+#ifdef CONFIG_OF
+
+/* Initial value for SRC control register: all timers use MXTAL/8 source */
+#define SRC_CR_INIT_MASK	0x00007fff
+#define SRC_CR_INIT_VAL		0x2aaa8000
+
+static void __init cpu8815_timer_init_of(void)
+{
+	struct device_node *mtu;
+	void __iomem *base;
+	int irq;
+	u32 src_cr;
+
+	/* We need this to be up now */
+	nomadik_clk_init();
+
+	mtu = of_find_node_by_path("/mtu0");
+	if (!mtu)
+		return;
+	base = of_iomap(mtu, 0);
+	if (WARN_ON(!base))
+		return;
+	irq = irq_of_parse_and_map(mtu, 0);
+
+	pr_info("Remapped MTU @ %p, irq: %d\n", base, irq);
+
+	/* Configure timer sources in "system reset controller" ctrl reg */
+	src_cr = readl(base);
+	src_cr &= SRC_CR_INIT_MASK;
+	src_cr |= SRC_CR_INIT_VAL;
+	writel(src_cr, base);
+
+	nmdk_timer_init(base, irq);
+}
+
+/* These are mostly to get the right device names for the clock lookups */
+static struct of_dev_auxdata cpu8815_auxdata_lookup[] __initdata = {
+	OF_DEV_AUXDATA("arm,primecell", NOMADIK_UART0_BASE,
+		"uart0", NULL),
+	OF_DEV_AUXDATA("arm,primecell", NOMADIK_UART1_BASE,
+		"uart1", NULL),
+	{ /* sentinel */ },
+};
+
+static void __init cpu8815_init_of(void)
+{
+#ifdef CONFIG_CACHE_L2X0
+	/* At full speed latency must be >=2, so 0x249 in low bits */
+	l2x0_of_init(0x00730249, 0xfe000fff);
+#endif
+	of_platform_populate(NULL, of_default_bus_match_table,
+			cpu8815_auxdata_lookup, NULL);
+}
+
+static const char * cpu8815_board_compat[] = {
+	"calaosystems,usb-s8815",
+	NULL,
+};
+
+DT_MACHINE_START(NOMADIK_DT, "Nomadik STn8815")
+	.map_io		= cpu8815_map_io,
+	.init_irq	= irqchip_init,
+	.init_time	= cpu8815_timer_init_of,
+	.init_machine	= cpu8815_init_of,
+	.restart	= cpu8815_restart,
+	.dt_compat      = cpu8815_board_compat,
+MACHINE_END
+
+#endif