File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/mips/netlogic/xlr/fmn.c b/arch/mips/netlogic/xlr/fmn.c
new file mode 100644
index 0000000..d428e84
--- /dev/null
+++ b/arch/mips/netlogic/xlr/fmn.c
@@ -0,0 +1,204 @@
+/*
+ * Copyright (c) 2003-2012 Broadcom Corporation
+ * All Rights Reserved
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the Broadcom
+ * license below:
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY BROADCOM ``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 BROADCOM OR CONTRIBUTORS 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/irqreturn.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+
+#include <asm/mipsregs.h>
+#include <asm/netlogic/interrupt.h>
+#include <asm/netlogic/xlr/fmn.h>
+#include <asm/netlogic/common.h>
+
+#define COP2_CC_INIT_CPU_DEST(dest, conf) \
+do { \
+	nlm_write_c2_cc##dest(0, conf[(dest * 8) + 0]); \
+	nlm_write_c2_cc##dest(1, conf[(dest * 8) + 1]); \
+	nlm_write_c2_cc##dest(2, conf[(dest * 8) + 2]); \
+	nlm_write_c2_cc##dest(3, conf[(dest * 8) + 3]); \
+	nlm_write_c2_cc##dest(4, conf[(dest * 8) + 4]); \
+	nlm_write_c2_cc##dest(5, conf[(dest * 8) + 5]); \
+	nlm_write_c2_cc##dest(6, conf[(dest * 8) + 6]); \
+	nlm_write_c2_cc##dest(7, conf[(dest * 8) + 7]); \
+} while (0)
+
+struct fmn_message_handler {
+	void (*action)(int, int, int, int, struct nlm_fmn_msg *, void *);
+	void *arg;
+} msg_handlers[128];
+
+/*
+ * FMN interrupt handler. We configure the FMN so that any messages in
+ * any of the CPU buckets will trigger an interrupt on the CPU.
+ * The message can be from any device on the FMN (like NAE/SAE/DMA).
+ * The source station id is used to figure out which of the registered
+ * handlers have to be called.
+ */
+static irqreturn_t fmn_message_handler(int irq, void *data)
+{
+	struct fmn_message_handler *hndlr;
+	int bucket, rv;
+	int size = 0, code = 0, src_stnid = 0;
+	struct nlm_fmn_msg msg;
+	uint32_t mflags, bkt_status;
+
+	mflags = nlm_cop2_enable_irqsave();
+	/* Disable message ring interrupt */
+	nlm_fmn_setup_intr(irq, 0);
+	while (1) {
+		/* 8 bkts per core, [24:31] each bit represents one bucket
+		 * Bit is Zero if bucket is not empty */
+		bkt_status = (nlm_read_c2_status0() >> 24) & 0xff;
+		if (bkt_status == 0xff)
+			break;
+		for (bucket = 0; bucket < 8; bucket++) {
+			/* Continue on empty bucket */
+			if (bkt_status & (1 << bucket))
+				continue;
+			rv = nlm_fmn_receive(bucket, &size, &code, &src_stnid,
+						&msg);
+			if (rv != 0)
+				continue;
+
+			hndlr = &msg_handlers[src_stnid];
+			if (hndlr->action == NULL)
+				pr_warn("No msgring handler for stnid %d\n",
+						src_stnid);
+			else {
+				nlm_cop2_disable_irqrestore(mflags);
+				hndlr->action(bucket, src_stnid, size, code,
+					&msg, hndlr->arg);
+				mflags = nlm_cop2_enable_irqsave();
+			}
+		}
+	};
+	/* Enable message ring intr, to any thread in core */
+	nlm_fmn_setup_intr(irq, (1 << nlm_threads_per_core) - 1);
+	nlm_cop2_disable_irqrestore(mflags);
+	return IRQ_HANDLED;
+}
+
+struct irqaction fmn_irqaction = {
+	.handler = fmn_message_handler,
+	.flags = IRQF_PERCPU,
+	.name = "fmn",
+};
+
+void xlr_percpu_fmn_init(void)
+{
+	struct xlr_fmn_info *cpu_fmn_info;
+	int *bucket_sizes;
+	uint32_t flags;
+	int id;
+
+	BUG_ON(nlm_thread_id() != 0);
+	id = nlm_core_id();
+
+	bucket_sizes = xlr_board_fmn_config.bucket_size;
+	cpu_fmn_info = &xlr_board_fmn_config.cpu[id];
+	flags = nlm_cop2_enable_irqsave();
+
+	/* Setup bucket sizes for the core. */
+	nlm_write_c2_bucksize(0, bucket_sizes[id * 8 + 0]);
+	nlm_write_c2_bucksize(1, bucket_sizes[id * 8 + 1]);
+	nlm_write_c2_bucksize(2, bucket_sizes[id * 8 + 2]);
+	nlm_write_c2_bucksize(3, bucket_sizes[id * 8 + 3]);
+	nlm_write_c2_bucksize(4, bucket_sizes[id * 8 + 4]);
+	nlm_write_c2_bucksize(5, bucket_sizes[id * 8 + 5]);
+	nlm_write_c2_bucksize(6, bucket_sizes[id * 8 + 6]);
+	nlm_write_c2_bucksize(7, bucket_sizes[id * 8 + 7]);
+
+	/*
+	 * For sending FMN messages, we need credits on the destination
+	 * bucket. Program the credits this core has on the 128 possible
+	 * destination buckets.
+	 * We cannot use a loop here, because the the first argument has
+	 * to be a constant integer value.
+	 */
+	COP2_CC_INIT_CPU_DEST(0, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(1, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(2, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(3, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(4, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(5, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(6, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(7, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(8, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(9, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(10, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(11, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(12, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(13, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(14, cpu_fmn_info->credit_config);
+	COP2_CC_INIT_CPU_DEST(15, cpu_fmn_info->credit_config);
+
+	/* enable FMN interrupts on this CPU */
+	nlm_fmn_setup_intr(IRQ_FMN, (1 << nlm_threads_per_core) - 1);
+	nlm_cop2_disable_irqrestore(flags);
+}
+
+
+/*
+ * Register a FMN message handler with respect to the source station id
+ * @stnid: source station id
+ * @action: Handler function pointer
+ */
+int nlm_register_fmn_handler(int start_stnid, int end_stnid,
+	void (*action)(int, int, int, int, struct nlm_fmn_msg *, void *),
+	void *arg)
+{
+	int sstnid;
+
+	for (sstnid = start_stnid; sstnid <= end_stnid; sstnid++) {
+		msg_handlers[sstnid].arg = arg;
+		smp_wmb();
+		msg_handlers[sstnid].action = action;
+	}
+	pr_debug("Registered FMN msg handler for stnid %d-%d\n",
+			start_stnid, end_stnid);
+	return 0;
+}
+
+void nlm_setup_fmn_irq(void)
+{
+	uint32_t flags;
+
+	/* setup irq only once */
+	setup_irq(IRQ_FMN, &fmn_irqaction);
+
+	flags = nlm_cop2_enable_irqsave();
+	nlm_fmn_setup_intr(IRQ_FMN, (1 << nlm_threads_per_core) - 1);
+	nlm_cop2_disable_irqrestore(flags);
+}