[MIPS] Routerboard 532: Support for base system

Signed-off-by: Phil Sutter <n0-1@freewrt.org>
Signed-off-by: Florian Fainelli <florian.fainelli@telecomint.eu>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 209 insertions, 0 deletions

diff --git a/arch/mips/rb532/irq.c b/arch/mips/rb532/irq.c
new file mode 100644
index 00000000000..c0d0f950caf
--- /dev/null
+++ b/arch/mips/rb532/irq.c
@@ -0,0 +1,209 @@
+/*
+ *  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.
+ *
+ *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
+ *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
+ *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
+ *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
+ *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
+ *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *  You should have received a copy of the  GNU General Public License along
+ *  with this program; if not, write  to the Free Software Foundation, Inc.,
+ *  675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Copyright 2002 MontaVista Software Inc.
+ * Author: MontaVista Software, Inc.
+ *              stevel@mvista.com or source@mvista.com
+ */
+
+#include <linux/bitops.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel_stat.h>
+#include <linux/module.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/timex.h>
+#include <linux/slab.h>
+#include <linux/random.h>
+#include <linux/delay.h>
+
+#include <asm/bootinfo.h>
+#include <asm/time.h>
+#include <asm/mipsregs.h>
+#include <asm/system.h>
+
+#include <asm/mach-rc32434/rc32434.h>
+
+struct intr_group {
+	u32 mask;	/* mask of valid bits in pending/mask registers */
+	volatile u32 *base_addr;
+};
+
+#define RC32434_NR_IRQS  (GROUP4_IRQ_BASE + 32)
+
+#if (NR_IRQS < RC32434_NR_IRQS)
+#error Too little irqs defined. Did you override <asm/irq.h> ?
+#endif
+
+static const struct intr_group intr_group[NUM_INTR_GROUPS] = {
+	{
+		.mask	= 0x0000efff,
+		.base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 0 * IC_GROUP_OFFSET)},
+	{
+		.mask	= 0x00001fff,
+		.base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 1 * IC_GROUP_OFFSET)},
+	{
+		.mask	= 0x00000007,
+		.base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 2 * IC_GROUP_OFFSET)},
+	{
+		.mask	= 0x0003ffff,
+		.base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 3 * IC_GROUP_OFFSET)},
+	{
+		.mask	= 0xffffffff,
+		.base_addr = (u32 *) KSEG1ADDR(IC_GROUP0_PEND + 4 * IC_GROUP_OFFSET)}
+};
+
+#define READ_PEND(base) (*(base))
+#define READ_MASK(base) (*(base + 2))
+#define WRITE_MASK(base, val) (*(base + 2) = (val))
+
+static inline int irq_to_group(unsigned int irq_nr)
+{
+	return (irq_nr - GROUP0_IRQ_BASE) >> 5;
+}
+
+static inline int group_to_ip(unsigned int group)
+{
+	return group + 2;
+}
+
+static inline void enable_local_irq(unsigned int ip)
+{
+	int ipnum = 0x100 << ip;
+
+	set_c0_status(ipnum);
+}
+
+static inline void disable_local_irq(unsigned int ip)
+{
+	int ipnum = 0x100 << ip;
+
+	clear_c0_status(ipnum);
+}
+
+static inline void ack_local_irq(unsigned int ip)
+{
+	int ipnum = 0x100 << ip;
+
+	clear_c0_cause(ipnum);
+}
+
+static void rb532_enable_irq(unsigned int irq_nr)
+{
+	int ip = irq_nr - GROUP0_IRQ_BASE;
+	unsigned int group, intr_bit;
+	volatile unsigned int *addr;
+
+	if (ip < 0)
+		enable_local_irq(irq_nr);
+	else {
+		group = ip >> 5;
+
+		ip &= (1 << 5) - 1;
+		intr_bit = 1 << ip;
+
+		enable_local_irq(group_to_ip(group));
+
+		addr = intr_group[group].base_addr;
+		WRITE_MASK(addr, READ_MASK(addr) & ~intr_bit);
+	}
+}
+
+static void rb532_disable_irq(unsigned int irq_nr)
+{
+	int ip = irq_nr - GROUP0_IRQ_BASE;
+	unsigned int group, intr_bit, mask;
+	volatile unsigned int *addr;
+
+	if (ip < 0) {
+		disable_local_irq(irq_nr);
+	} else {
+		group = ip >> 5;
+
+		ip &= (1 << 5) - 1;
+		intr_bit = 1 << ip;
+		addr = intr_group[group].base_addr;
+		mask = READ_MASK(addr);
+		mask |= intr_bit;
+		WRITE_MASK(addr, mask);
+
+		/*
+		 * if there are no more interrupts enabled in this
+		 * group, disable corresponding IP
+		 */
+		if (mask == intr_group[group].mask)
+			disable_local_irq(group_to_ip(group));
+	}
+}
+
+static void rb532_mask_and_ack_irq(unsigned int irq_nr)
+{
+	rb532_disable_irq(irq_nr);
+	ack_local_irq(group_to_ip(irq_to_group(irq_nr)));
+}
+
+static struct irq_chip rc32434_irq_type = {
+	.name		= "RB532",
+	.ack		= rb532_disable_irq,
+	.mask		= rb532_disable_irq,
+	.mask_ack	= rb532_mask_and_ack_irq,
+	.unmask		= rb532_enable_irq,
+};
+
+void __init arch_init_irq(void)
+{
+	int i;
+
+	pr_info("Initializing IRQ's: %d out of %d\n", RC32434_NR_IRQS, NR_IRQS);
+
+	for (i = 0; i < RC32434_NR_IRQS; i++)
+		set_irq_chip_and_handler(i,  &rc32434_irq_type,
+					handle_level_irq);
+}
+
+/* Main Interrupt dispatcher */
+asmlinkage void plat_irq_dispatch(void)
+{
+	unsigned int ip, pend, group;
+	volatile unsigned int *addr;
+	unsigned int cp0_cause = read_c0_cause() & read_c0_status();
+
+	if (cp0_cause & CAUSEF_IP7) {
+		do_IRQ(7);
+	} else {
+		ip = (cp0_cause & 0x7c00);
+		if (ip) {
+			group = 21 + (fls(ip) - 32);
+
+			addr = intr_group[group].base_addr;
+
+			pend = READ_PEND(addr);
+			pend &= ~READ_MASK(addr);	/* only unmasked interrupts */
+			pend = 39 + (fls(pend) - 32);
+			do_IRQ((group << 5) + pend);
+		}
+	}
+}