initial suport for Alphascale ASM9260

arch/arm/Kconfig.debug +10 -0

+	config DEBUG_ASM9260_UART
+		bool "Kernel low-level debugging via asm9260 UART"
+		depends on MACH_ASM9260
+		help
+		  Say Y here if you want the debug print routines to direct
+		  their output to an UART or USART port on asm9260 based
+		  machines.
+
+		    DEBUG_UART_PHYS | DEBUG_UART_VIRT
+

Quoted 14 lines

arch/arm/Kconfig.debug +14 -0

+	config DEBUG_ASM9260_UART
+		bool "Kernel low-level debugging via asm9260 UART"
+		depends on MACH_ASM9260
+		help
+		  Say Y here if you want the debug print routines to direct
+		  their output to an UART or USART port on asm9260 based
+		  machines.
+
+		    DEBUG_UART_PHYS | DEBUG_UART_VIRT
+
+		    0x80000000      | 0xf0000000     | UART0
+		    0x80004000      | 0xf0004000     | UART1
+		    0x80008000      | 0xf0008000     | UART2
+		    0x8000c000      | 0xf000c000     | UART3

arch/arm/Kconfig.debug choice · line 115

Quoted 6 lines

arch/arm/Kconfig.debug +6 -0

+		    0x80010000      | 0xf0010000     | UART4
+		    0x80014000      | 0xf0014000     | UART5
+		    0x80018000      | 0xf0018000     | UART6
+		    0x8001c000      | 0xf001c000     | UART7
+		    0x80020000      | 0xf0020000     | UART8
+		    0x80024000      | 0xf0024000     | UART9

What's the point of having this list in Kconfig?

drivers/irqchip/irq-mxs.c static void icoll_ack_irq(struct irq_data *d) · line 116

Quoted 5 lines

static void icoll_unmask_irq(struct irq_data *d)
{

drivers/irqchip/irq-mxs.c +1 -2

-	__raw_writel(BM_ICOLL_INTR_ENABLE,
-			icoll_priv.intr + SET_REG + HW_ICOLL_INTERRUPTn(d->hwirq));
+	mutex_lock(&icoll_lock);

And how's that supposed to work? You certainly did not run this code with even the simplest debugging options enabled. Not to talk about lockdep or such.

Am 21.10.2014 um 09:27 schrieb Thomas Gleixner:

Quoted 10 lines · Oleksij Rempel

drivers/irqchip/irq-mxs.c static void icoll_ack_irq(struct irq_data *d) · line 116

Quoted 5 lines

static void icoll_unmask_irq(struct irq_data *d)
{

drivers/irqchip/irq-mxs.c +1 -2

-	__raw_writel(BM_ICOLL_INTR_ENABLE,
-			icoll_priv.intr + SET_REG + HW_ICOLL_INTERRUPTn(d->hwirq));
+	mutex_lock(&icoll_lock);

And how's that supposed to work? You certainly did not run this code with even the simplest debugging options enabled. Not to talk about lockdep or such.

Are there any check list what debugging options should be enabled?

Quoted 13 lines

Am 21.10.2014 um 09:27 schrieb Thomas Gleixner:

Quoted 10 lines · Oleksij Rempel

drivers/irqchip/irq-mxs.c static void icoll_ack_irq(struct irq_data *d) · line 116

Quoted 5 lines

static void icoll_unmask_irq(struct irq_data *d)
{

drivers/irqchip/irq-mxs.c +1 -2

-	__raw_writel(BM_ICOLL_INTR_ENABLE,
-			icoll_priv.intr + SET_REG + HW_ICOLL_INTERRUPTn(d->hwirq));
+	mutex_lock(&icoll_lock);

And how's that supposed to work? You certainly did not run this code with even the simplest debugging options enabled. Not to talk about lockdep or such.

Quoted 1 line

Are there any check list what debugging options should be enabled?

# ls Documentation | grep -i checklist

Perhaps?

In some cases asm9260 looks similar to iMX2x. One of exceptions is timer controller. So this patch introduces new driver for this special case.

Signed-off-by Oleksij Rempel <[email protected]>

---
  drivers/clocksource/Kconfig         |   4 +
  drivers/clocksource/Makefile        |   1 +
  drivers/clocksource/asm9260_timer.c | 220 ++++++++++++++++++++++++++++++++++++
  3 files changed, 225 insertions(+)

create mode 100644 drivers/clocksource/asm9260_timer.c

drivers/clocksource/Kconfig +4 -0

index cfd6519..6a03d34 100644
@@ -216,4 +216,8 @@ config CLKSRC_VERSATILE
  	  ARM Versatile, RealView and Versatile Express reference
  	  platforms.
 
+config ASM9260_TIMER
+	select CLKSRC_MMIO
+	bool
+
  endmenu

drivers/clocksource/Makefile +1 -0

index 7fd9fd1..fc93854 100644
@@ -44,3 +44,4 @@ obj-$(CONFIG_CLKSRC_METAG_GENERIC)	+= metag_generic.o
  obj-$(CONFIG_ARCH_HAS_TICK_BROADCAST)	+= dummy_timer.o
  obj-$(CONFIG_ARCH_KEYSTONE)		+= timer-keystone.o
  obj-$(CONFIG_CLKSRC_VERSATILE)		+= versatile.o
+obj-$(CONFIG_ASM9260_TIMER)		+= asm9260_timer.o

drivers/clocksource/asm9260_timer.c new file +220 -0

new file mode 100644
index 0000000..12cab34
@@ -0,0 +1,220 @@
+/*
+ * Copyright (C) 2014 Oleksij Rempel <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/clk.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/bitops.h>
+
+#define DRIVER_NAME	"asm9260-timer"
+
+/*
+ * this device provide 4 offsets for each register:
+ * 0x0 - plain read write mode
+ * 0x4 - set mode, OR logic.
+ * 0x8 - clr mode, XOR logic.
+ * 0xc - togle mode.
+ */
+#define SET_REG 4
+#define CLR_REG 8
+
+#define HW_IR           0x0000 /* RW. Interrupt */
+#define BM_IR_CR0	BIT(4)
+#define BM_IR_MR3	BIT(3)
+#define BM_IR_MR2	BIT(2)
+#define BM_IR_MR1	BIT(1)
+#define BM_IR_MR0	BIT(0)
+
+#define HW_TCR		0x0010 /* RW. Timer controller */
+/* BM_C*_RST
+ * Timer Counter and the Prescale Counter are synchronously reset on the
+ * next positive edge of PCLK. The counters remain reset until TCR[1] is
+ * returned to zero. */
+#define BM_C3_RST	BIT(7)
+#define BM_C2_RST	BIT(6)
+#define BM_C1_RST	BIT(5)
+#define BM_C0_RST	BIT(4)
+/* BM_C*_EN
+ * 1 - Timer Counter and Prescale Counter are enabled for counting
+ * 0 - counters are disabled */
+#define BM_C3_EN	BIT(3)
+#define BM_C2_EN	BIT(2)
+#define BM_C1_EN	BIT(1)
+#define BM_C0_EN	BIT(0)
+
+#define HW_DIR		0x0020 /* RW. Direction? */
+/* 00 - count up
+ * 01 - count down
+ * 10 - ?? 2^n/2 */
+#define BM_DIR_COUNT_UP		0
+#define BM_DIR_COUNT_DOWN	1
+#define BM_DIR0_SHIFT	0
+#define BM_DIR1_SHIFT	4
+#define BM_DIR2_SHIFT	8
+#define BM_DIR3_SHIFT	12
+#define BM_DIR_DEFAULT		(BM_DIR_COUNT_UP << BM_DIR0_SHIFT | \
+				 BM_DIR_COUNT_UP << BM_DIR1_SHIFT | \
+				 BM_DIR_COUNT_UP << BM_DIR2_SHIFT | \
+				 BM_DIR_COUNT_UP << BM_DIR3_SHIFT)
+
+#define HW_TC0		0x0030 /* RO. Timer counter 0 */
+/* HW_TC*. Timer counter owerflow (0xffff.ffff to 0x0000.0000) do not generate
+ * interrupt. This registers can be used to detect overflow */
+#define HW_TC1          0x0040
+#define HW_TC2		0x0050
+#define HW_TC3		0x0060
+
+#define HW_PR		0x0070 /* RW. prescaler */
+#define BM_PR_DISABLE	0
+#define HW_PC		0x0080 /* RO. Prescaler counter */
+#define HW_MCR		0x0090 /* RW. Match control */
+/* enable interrupt on match */
+#define BM_MCR_INT_EN(n)	(1 << (n * 3 + 0))
+/* enable TC reset on match */
+#define BM_MCR_RES_EN(n)	(1 << (n * 3 + 1))
+/* enable stop TC on match */
+#define BM_MCR_STOP_EN(n)	(1 << (n * 3 + 2))
+
+#define HW_MR0		0x00a0 /* RW. Match reg */
+#define HW_MR1		0x00b0
+#define HW_MR2		0x00C0
+#define HW_MR3		0x00D0
+
+#define HW_CTCR		0x0180 /* Counter control */
+#define BM_CTCR0_SHIFT	0
+#define BM_CTCR1_SHIFT	2
+#define BM_CTCR2_SHIFT	4
+#define BM_CTCR3_SHIFT	6
+#define BM_CTCR_TM	0	/* Timer mode. Every rising PCLK edge. */
+#define BM_CTCR_DEFAULT	(BM_CTCR_TM << BM_CTCR0_SHIFT | \
+			 BM_CTCR_TM << BM_CTCR1_SHIFT | \
+			 BM_CTCR_TM << BM_CTCR2_SHIFT | \
+			 BM_CTCR_TM << BM_CTCR3_SHIFT)
+
+static struct asm9260_timer_priv {
+	void __iomem *base;
+	unsigned long ticks_per_jiffy;
+} priv;
+
+static int asm9260_timer_set_next_event(unsigned long delta,
+					 struct clock_event_device *evt)
+{
+	/* configure match count for TC0 */
+	writel_relaxed(delta, priv.base + HW_MR0);
+	/* enable TC0 */
+	writel_relaxed(BM_C0_EN, priv.base + HW_TCR + SET_REG);
+	return 0;
+}
+
+static void asm9260_timer_set_mode(enum clock_event_mode mode,
+				    struct clock_event_device *evt)
+{
+	/* stop timer0 */
+	writel_relaxed(BM_C0_EN, priv.base + HW_TCR + CLR_REG);
+
+	switch (mode) {
+	case CLOCK_EVT_MODE_PERIODIC:
+		/* disable reset and stop on match */
+		writel_relaxed(BM_MCR_RES_EN(0) | BM_MCR_STOP_EN(0),
+				priv.base + HW_MCR + CLR_REG);
+		/* configure match count for TC0 */
+		writel_relaxed(priv.ticks_per_jiffy, priv.base + HW_MR0);
+		/* enable TC0 */
+		writel_relaxed(BM_C0_EN, priv.base + HW_TCR + SET_REG);
+		break;
+	case CLOCK_EVT_MODE_ONESHOT:
+		/* enable reset and stop on match */
+		writel_relaxed(BM_MCR_RES_EN(0) | BM_MCR_STOP_EN(0),
+				priv.base + HW_MCR + SET_REG);
+		break;
+	default:
+		break;
+	}
+}
+
+static struct clock_event_device event_dev = {
+	.name		= DRIVER_NAME,
+	.rating		= 200,
+	.features       = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+	.set_next_event	= asm9260_timer_set_next_event,
+	.set_mode	= asm9260_timer_set_mode,
+};
+
+static irqreturn_t asm9260_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	evt->event_handler(evt);
+
+	writel_relaxed(BM_IR_MR0, priv.base + HW_IR);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * ---------------------------------------------------------------------------
+ * Timer initialization
+ * ---------------------------------------------------------------------------
+ */
+static void __init asm9260_timer_init(struct device_node *np)
+{
+	int irq;
+	struct clk *clk;
+	int ret;
+	unsigned long rate;
+
+	priv.base = of_io_request_and_map(np, 0, DRIVER_NAME);
+	if (!priv.base)
+		panic("%s: unable to map resource", DRIVER_NAME);
+
+	clk = of_clk_get(np, 0);
+
+	ret = clk_prepare_enable(clk);
+	if (ret)
+		panic("Failed to enable clk!\n");
+
+	irq = irq_of_parse_and_map(np, 0);
+	ret = request_irq(irq, asm9260_timer_interrupt, IRQF_TIMER,
+			DRIVER_NAME, &event_dev);
+	if (ret)
+		panic("Failed to setup irq!\n");
+
+	/* set all timers for count-up */
+	writel_relaxed(BM_DIR_DEFAULT, priv.base + HW_DIR);
+	/* disable divider */
+	writel_relaxed(BM_PR_DISABLE, priv.base + HW_PR);
+	/* make sure all timers use every rising PCLK edge. */
+	writel_relaxed(BM_CTCR_DEFAULT, priv.base + HW_CTCR);
+	/* enable interrupt for TC0 and clean setting for all other lines */
+	writel_relaxed(BM_MCR_INT_EN(0) , priv.base + HW_MCR);
+
+	rate = clk_get_rate(clk);
+	clocksource_mmio_init(priv.base + HW_TC1, DRIVER_NAME, rate,
+			200, 32, clocksource_mmio_readl_up);
+
+	/* Seems like we can't use counter without match register even if
+	 * actions for MR are disabled. So, set MR to max value. */
+	writel_relaxed(0xffffffff, priv.base + HW_MR1);
+	/* enable TC1 */
+	writel_relaxed(BM_C1_EN, priv.base + HW_TCR + SET_REG);
+
+	priv.ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ);
+	event_dev.cpumask = cpumask_of(0);
+	clockevents_config_and_register(&event_dev, rate, 0x2c00, 0xfffffffe);
+}
+CLOCKSOURCE_OF_DECLARE(asm9260_timer, "alphascale,asm9260-timer",
+		asm9260_timer_init);