MIPS: BCM63xx: Add support for the Broadcom BCM63xx family of SOCs.

Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 253 insertions, 0 deletions

diff --git a/arch/mips/bcm63xx/irq.c b/arch/mips/bcm63xx/irq.c
new file mode 100644
index 0000000..a0c5cd1
--- /dev/null
+++ b/arch/mips/bcm63xx/irq.c
@@ -0,0 +1,253 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
+ * Copyright (C) 2008 Nicolas Schichan <nschichan@freebox.fr>
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <asm/irq_cpu.h>
+#include <asm/mipsregs.h>
+#include <bcm63xx_cpu.h>
+#include <bcm63xx_regs.h>
+#include <bcm63xx_io.h>
+#include <bcm63xx_irq.h>
+
+/*
+ * dispatch internal devices IRQ (uart, enet, watchdog, ...). do not
+ * prioritize any interrupt relatively to another. the static counter
+ * will resume the loop where it ended the last time we left this
+ * function.
+ */
+static void bcm63xx_irq_dispatch_internal(void)
+{
+	u32 pending;
+	static int i;
+
+	pending = bcm_perf_readl(PERF_IRQMASK_REG) &
+		bcm_perf_readl(PERF_IRQSTAT_REG);
+
+	if (!pending)
+		return ;
+
+	while (1) {
+		int to_call = i;
+
+		i = (i + 1) & 0x1f;
+		if (pending & (1 << to_call)) {
+			do_IRQ(to_call + IRQ_INTERNAL_BASE);
+			break;
+		}
+	}
+}
+
+asmlinkage void plat_irq_dispatch(void)
+{
+	u32 cause;
+
+	do {
+		cause = read_c0_cause() & read_c0_status() & ST0_IM;
+
+		if (!cause)
+			break;
+
+		if (cause & CAUSEF_IP7)
+			do_IRQ(7);
+		if (cause & CAUSEF_IP2)
+			bcm63xx_irq_dispatch_internal();
+		if (cause & CAUSEF_IP3)
+			do_IRQ(IRQ_EXT_0);
+		if (cause & CAUSEF_IP4)
+			do_IRQ(IRQ_EXT_1);
+		if (cause & CAUSEF_IP5)
+			do_IRQ(IRQ_EXT_2);
+		if (cause & CAUSEF_IP6)
+			do_IRQ(IRQ_EXT_3);
+	} while (1);
+}
+
+/*
+ * internal IRQs operations: only mask/unmask on PERF irq mask
+ * register.
+ */
+static inline void bcm63xx_internal_irq_mask(unsigned int irq)
+{
+	u32 mask;
+
+	irq -= IRQ_INTERNAL_BASE;
+	mask = bcm_perf_readl(PERF_IRQMASK_REG);
+	mask &= ~(1 << irq);
+	bcm_perf_writel(mask, PERF_IRQMASK_REG);
+}
+
+static void bcm63xx_internal_irq_unmask(unsigned int irq)
+{
+	u32 mask;
+
+	irq -= IRQ_INTERNAL_BASE;
+	mask = bcm_perf_readl(PERF_IRQMASK_REG);
+	mask |= (1 << irq);
+	bcm_perf_writel(mask, PERF_IRQMASK_REG);
+}
+
+static unsigned int bcm63xx_internal_irq_startup(unsigned int irq)
+{
+	bcm63xx_internal_irq_unmask(irq);
+	return 0;
+}
+
+/*
+ * external IRQs operations: mask/unmask and clear on PERF external
+ * irq control register.
+ */
+static void bcm63xx_external_irq_mask(unsigned int irq)
+{
+	u32 reg;
+
+	irq -= IRQ_EXT_BASE;
+	reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
+	reg &= ~EXTIRQ_CFG_MASK(irq);
+	bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
+}
+
+static void bcm63xx_external_irq_unmask(unsigned int irq)
+{
+	u32 reg;
+
+	irq -= IRQ_EXT_BASE;
+	reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
+	reg |= EXTIRQ_CFG_MASK(irq);
+	bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
+}
+
+static void bcm63xx_external_irq_clear(unsigned int irq)
+{
+	u32 reg;
+
+	irq -= IRQ_EXT_BASE;
+	reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
+	reg |= EXTIRQ_CFG_CLEAR(irq);
+	bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
+}
+
+static unsigned int bcm63xx_external_irq_startup(unsigned int irq)
+{
+	set_c0_status(0x100 << (irq - IRQ_MIPS_BASE));
+	irq_enable_hazard();
+	bcm63xx_external_irq_unmask(irq);
+	return 0;
+}
+
+static void bcm63xx_external_irq_shutdown(unsigned int irq)
+{
+	bcm63xx_external_irq_mask(irq);
+	clear_c0_status(0x100 << (irq - IRQ_MIPS_BASE));
+	irq_disable_hazard();
+}
+
+static int bcm63xx_external_irq_set_type(unsigned int irq,
+					 unsigned int flow_type)
+{
+	u32 reg;
+	struct irq_desc *desc = irq_desc + irq;
+
+	irq -= IRQ_EXT_BASE;
+
+	flow_type &= IRQ_TYPE_SENSE_MASK;
+
+	if (flow_type == IRQ_TYPE_NONE)
+		flow_type = IRQ_TYPE_LEVEL_LOW;
+
+	reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
+	switch (flow_type) {
+	case IRQ_TYPE_EDGE_BOTH:
+		reg &= ~EXTIRQ_CFG_LEVELSENSE(irq);
+		reg |= EXTIRQ_CFG_BOTHEDGE(irq);
+		break;
+
+	case IRQ_TYPE_EDGE_RISING:
+		reg &= ~EXTIRQ_CFG_LEVELSENSE(irq);
+		reg |= EXTIRQ_CFG_SENSE(irq);
+		reg &= ~EXTIRQ_CFG_BOTHEDGE(irq);
+		break;
+
+	case IRQ_TYPE_EDGE_FALLING:
+		reg &= ~EXTIRQ_CFG_LEVELSENSE(irq);
+		reg &= ~EXTIRQ_CFG_SENSE(irq);
+		reg &= ~EXTIRQ_CFG_BOTHEDGE(irq);
+		break;
+
+	case IRQ_TYPE_LEVEL_HIGH:
+		reg |= EXTIRQ_CFG_LEVELSENSE(irq);
+		reg |= EXTIRQ_CFG_SENSE(irq);
+		break;
+
+	case IRQ_TYPE_LEVEL_LOW:
+		reg |= EXTIRQ_CFG_LEVELSENSE(irq);
+		reg &= ~EXTIRQ_CFG_SENSE(irq);
+		break;
+
+	default:
+		printk(KERN_ERR "bogus flow type combination given !\n");
+		return -EINVAL;
+	}
+	bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
+
+	if (flow_type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))  {
+		desc->status |= IRQ_LEVEL;
+		desc->handle_irq = handle_level_irq;
+	} else {
+		desc->handle_irq = handle_edge_irq;
+	}
+
+	return 0;
+}
+
+static struct irq_chip bcm63xx_internal_irq_chip = {
+	.name		= "bcm63xx_ipic",
+	.startup	= bcm63xx_internal_irq_startup,
+	.shutdown	= bcm63xx_internal_irq_mask,
+
+	.mask		= bcm63xx_internal_irq_mask,
+	.mask_ack	= bcm63xx_internal_irq_mask,
+	.unmask		= bcm63xx_internal_irq_unmask,
+};
+
+static struct irq_chip bcm63xx_external_irq_chip = {
+	.name		= "bcm63xx_epic",
+	.startup	= bcm63xx_external_irq_startup,
+	.shutdown	= bcm63xx_external_irq_shutdown,
+
+	.ack		= bcm63xx_external_irq_clear,
+
+	.mask		= bcm63xx_external_irq_mask,
+	.unmask		= bcm63xx_external_irq_unmask,
+
+	.set_type	= bcm63xx_external_irq_set_type,
+};
+
+static struct irqaction cpu_ip2_cascade_action = {
+	.handler	= no_action,
+	.name		= "cascade_ip2",
+};
+
+void __init arch_init_irq(void)
+{
+	int i;
+
+	mips_cpu_irq_init();
+	for (i = IRQ_INTERNAL_BASE; i < NR_IRQS; ++i)
+		set_irq_chip_and_handler(i, &bcm63xx_internal_irq_chip,
+					 handle_level_irq);
+
+	for (i = IRQ_EXT_BASE; i < IRQ_EXT_BASE + 4; ++i)
+		set_irq_chip_and_handler(i, &bcm63xx_external_irq_chip,
+					 handle_edge_irq);
+
+	setup_irq(IRQ_MIPS_BASE + 2, &cpu_ip2_cascade_action);
+}