arch/tile: provide kernel support for the tilegx mPIPE shim

The TILE-Gx chip includes a packet-processing network engine called
mPIPE ("Multicore Programmable Intelligent Packet Engine").  This
change adds support for using the mPIPE engine from within the
kernel.  The engine has more functionality than is exposed here,
but to keep the kernel code and binary simpler, this is a subset
of the full API designed to enable standard Linux networking only.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

5 files changed, 1166 insertions, 0 deletions

diff --git a/arch/tile/gxio/Kconfig b/arch/tile/gxio/Kconfig
index ecd076c..8aeebb7 100644
--- a/arch/tile/gxio/Kconfig
+++ b/arch/tile/gxio/Kconfig
@@ -9,3 +9,9 @@ config TILE_GXIO
 config TILE_GXIO_DMA
 	bool
 	select TILE_GXIO
+
+# Support direct access to the TILE-Gx mPIPE hardware from kernel space.
+config TILE_GXIO_MPIPE
+	bool
+	select TILE_GXIO
+	select TILE_GXIO_DMA
diff --git a/arch/tile/gxio/Makefile b/arch/tile/gxio/Makefile
index 97ab468..130eec4 100644
--- a/arch/tile/gxio/Makefile
+++ b/arch/tile/gxio/Makefile
@@ -4,3 +4,4 @@
 
 obj-$(CONFIG_TILE_GXIO) += iorpc_globals.o kiorpc.o
 obj-$(CONFIG_TILE_GXIO_DMA) += dma_queue.o
+obj-$(CONFIG_TILE_GXIO_MPIPE) += mpipe.o iorpc_mpipe.o iorpc_mpipe_info.o
diff --git a/arch/tile/gxio/iorpc_mpipe.c b/arch/tile/gxio/iorpc_mpipe.c
new file mode 100644
index 0000000..31b87bf
--- /dev/null
+++ b/arch/tile/gxio/iorpc_mpipe.c
@@ -0,0 +1,529 @@
+/*
+ * Copyright 2012 Tilera Corporation. All Rights Reserved.
+ *
+ *   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, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+/* This file is machine-generated; DO NOT EDIT! */
+#include "gxio/iorpc_mpipe.h"
+
+struct alloc_buffer_stacks_param {
+	unsigned int count;
+	unsigned int first;
+	unsigned int flags;
+};
+
+int gxio_mpipe_alloc_buffer_stacks(gxio_mpipe_context_t * context,
+				   unsigned int count, unsigned int first,
+				   unsigned int flags)
+{
+	struct alloc_buffer_stacks_param temp;
+	struct alloc_buffer_stacks_param *params = &temp;
+
+	params->count = count;
+	params->first = first;
+	params->flags = flags;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params),
+			     GXIO_MPIPE_OP_ALLOC_BUFFER_STACKS);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_alloc_buffer_stacks);
+
+struct init_buffer_stack_aux_param {
+	union iorpc_mem_buffer buffer;
+	unsigned int stack;
+	unsigned int buffer_size_enum;
+};
+
+int gxio_mpipe_init_buffer_stack_aux(gxio_mpipe_context_t * context,
+				     void *mem_va, size_t mem_size,
+				     unsigned int mem_flags, unsigned int stack,
+				     unsigned int buffer_size_enum)
+{
+	int __result;
+	unsigned long long __cpa;
+	pte_t __pte;
+	struct init_buffer_stack_aux_param temp;
+	struct init_buffer_stack_aux_param *params = &temp;
+
+	__result = va_to_cpa_and_pte(mem_va, &__cpa, &__pte);
+	if (__result != 0)
+		return __result;
+	params->buffer.kernel.cpa = __cpa;
+	params->buffer.kernel.size = mem_size;
+	params->buffer.kernel.pte = __pte;
+	params->buffer.kernel.flags = mem_flags;
+	params->stack = stack;
+	params->buffer_size_enum = buffer_size_enum;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params),
+			     GXIO_MPIPE_OP_INIT_BUFFER_STACK_AUX);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_init_buffer_stack_aux);
+
+
+struct alloc_notif_rings_param {
+	unsigned int count;
+	unsigned int first;
+	unsigned int flags;
+};
+
+int gxio_mpipe_alloc_notif_rings(gxio_mpipe_context_t * context,
+				 unsigned int count, unsigned int first,
+				 unsigned int flags)
+{
+	struct alloc_notif_rings_param temp;
+	struct alloc_notif_rings_param *params = &temp;
+
+	params->count = count;
+	params->first = first;
+	params->flags = flags;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_MPIPE_OP_ALLOC_NOTIF_RINGS);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_alloc_notif_rings);
+
+struct init_notif_ring_aux_param {
+	union iorpc_mem_buffer buffer;
+	unsigned int ring;
+};
+
+int gxio_mpipe_init_notif_ring_aux(gxio_mpipe_context_t * context, void *mem_va,
+				   size_t mem_size, unsigned int mem_flags,
+				   unsigned int ring)
+{
+	int __result;
+	unsigned long long __cpa;
+	pte_t __pte;
+	struct init_notif_ring_aux_param temp;
+	struct init_notif_ring_aux_param *params = &temp;
+
+	__result = va_to_cpa_and_pte(mem_va, &__cpa, &__pte);
+	if (__result != 0)
+		return __result;
+	params->buffer.kernel.cpa = __cpa;
+	params->buffer.kernel.size = mem_size;
+	params->buffer.kernel.pte = __pte;
+	params->buffer.kernel.flags = mem_flags;
+	params->ring = ring;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params),
+			     GXIO_MPIPE_OP_INIT_NOTIF_RING_AUX);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_init_notif_ring_aux);
+
+struct request_notif_ring_interrupt_param {
+	union iorpc_interrupt interrupt;
+	unsigned int ring;
+};
+
+int gxio_mpipe_request_notif_ring_interrupt(gxio_mpipe_context_t * context,
+					    int inter_x, int inter_y,
+					    int inter_ipi, int inter_event,
+					    unsigned int ring)
+{
+	struct request_notif_ring_interrupt_param temp;
+	struct request_notif_ring_interrupt_param *params = &temp;
+
+	params->interrupt.kernel.x = inter_x;
+	params->interrupt.kernel.y = inter_y;
+	params->interrupt.kernel.ipi = inter_ipi;
+	params->interrupt.kernel.event = inter_event;
+	params->ring = ring;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params),
+			     GXIO_MPIPE_OP_REQUEST_NOTIF_RING_INTERRUPT);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_request_notif_ring_interrupt);
+
+struct enable_notif_ring_interrupt_param {
+	unsigned int ring;
+};
+
+int gxio_mpipe_enable_notif_ring_interrupt(gxio_mpipe_context_t * context,
+					   unsigned int ring)
+{
+	struct enable_notif_ring_interrupt_param temp;
+	struct enable_notif_ring_interrupt_param *params = &temp;
+
+	params->ring = ring;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params),
+			     GXIO_MPIPE_OP_ENABLE_NOTIF_RING_INTERRUPT);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_enable_notif_ring_interrupt);
+
+struct alloc_notif_groups_param {
+	unsigned int count;
+	unsigned int first;
+	unsigned int flags;
+};
+
+int gxio_mpipe_alloc_notif_groups(gxio_mpipe_context_t * context,
+				  unsigned int count, unsigned int first,
+				  unsigned int flags)
+{
+	struct alloc_notif_groups_param temp;
+	struct alloc_notif_groups_param *params = &temp;
+
+	params->count = count;
+	params->first = first;
+	params->flags = flags;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_MPIPE_OP_ALLOC_NOTIF_GROUPS);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_alloc_notif_groups);
+
+struct init_notif_group_param {
+	unsigned int group;
+	gxio_mpipe_notif_group_bits_t bits;
+};
+
+int gxio_mpipe_init_notif_group(gxio_mpipe_context_t * context,
+				unsigned int group,
+				gxio_mpipe_notif_group_bits_t bits)
+{
+	struct init_notif_group_param temp;
+	struct init_notif_group_param *params = &temp;
+
+	params->group = group;
+	params->bits = bits;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_MPIPE_OP_INIT_NOTIF_GROUP);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_init_notif_group);
+
+struct alloc_buckets_param {
+	unsigned int count;
+	unsigned int first;
+	unsigned int flags;
+};
+
+int gxio_mpipe_alloc_buckets(gxio_mpipe_context_t * context, unsigned int count,
+			     unsigned int first, unsigned int flags)
+{
+	struct alloc_buckets_param temp;
+	struct alloc_buckets_param *params = &temp;
+
+	params->count = count;
+	params->first = first;
+	params->flags = flags;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_MPIPE_OP_ALLOC_BUCKETS);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_alloc_buckets);
+
+struct init_bucket_param {
+	unsigned int bucket;
+	MPIPE_LBL_INIT_DAT_BSTS_TBL_t bucket_info;
+};
+
+int gxio_mpipe_init_bucket(gxio_mpipe_context_t * context, unsigned int bucket,
+			   MPIPE_LBL_INIT_DAT_BSTS_TBL_t bucket_info)
+{
+	struct init_bucket_param temp;
+	struct init_bucket_param *params = &temp;
+
+	params->bucket = bucket;
+	params->bucket_info = bucket_info;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_MPIPE_OP_INIT_BUCKET);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_init_bucket);
+
+struct alloc_edma_rings_param {
+	unsigned int count;
+	unsigned int first;
+	unsigned int flags;
+};
+
+int gxio_mpipe_alloc_edma_rings(gxio_mpipe_context_t * context,
+				unsigned int count, unsigned int first,
+				unsigned int flags)
+{
+	struct alloc_edma_rings_param temp;
+	struct alloc_edma_rings_param *params = &temp;
+
+	params->count = count;
+	params->first = first;
+	params->flags = flags;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_MPIPE_OP_ALLOC_EDMA_RINGS);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_alloc_edma_rings);
+
+struct init_edma_ring_aux_param {
+	union iorpc_mem_buffer buffer;
+	unsigned int ring;
+	unsigned int channel;
+};
+
+int gxio_mpipe_init_edma_ring_aux(gxio_mpipe_context_t * context, void *mem_va,
+				  size_t mem_size, unsigned int mem_flags,
+				  unsigned int ring, unsigned int channel)
+{
+	int __result;
+	unsigned long long __cpa;
+	pte_t __pte;
+	struct init_edma_ring_aux_param temp;
+	struct init_edma_ring_aux_param *params = &temp;
+
+	__result = va_to_cpa_and_pte(mem_va, &__cpa, &__pte);
+	if (__result != 0)
+		return __result;
+	params->buffer.kernel.cpa = __cpa;
+	params->buffer.kernel.size = mem_size;
+	params->buffer.kernel.pte = __pte;
+	params->buffer.kernel.flags = mem_flags;
+	params->ring = ring;
+	params->channel = channel;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_MPIPE_OP_INIT_EDMA_RING_AUX);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_init_edma_ring_aux);
+
+
+int gxio_mpipe_commit_rules(gxio_mpipe_context_t * context, const void *blob,
+			    size_t blob_size)
+{
+	const void *params = blob;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params, blob_size,
+			     GXIO_MPIPE_OP_COMMIT_RULES);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_commit_rules);
+
+struct register_client_memory_param {
+	unsigned int iotlb;
+	HV_PTE pte;
+	unsigned int flags;
+};
+
+int gxio_mpipe_register_client_memory(gxio_mpipe_context_t * context,
+				      unsigned int iotlb, HV_PTE pte,
+				      unsigned int flags)
+{
+	struct register_client_memory_param temp;
+	struct register_client_memory_param *params = &temp;
+
+	params->iotlb = iotlb;
+	params->pte = pte;
+	params->flags = flags;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params),
+			     GXIO_MPIPE_OP_REGISTER_CLIENT_MEMORY);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_register_client_memory);
+
+struct link_open_aux_param {
+	_gxio_mpipe_link_name_t name;
+	unsigned int flags;
+};
+
+int gxio_mpipe_link_open_aux(gxio_mpipe_context_t * context,
+			     _gxio_mpipe_link_name_t name, unsigned int flags)
+{
+	struct link_open_aux_param temp;
+	struct link_open_aux_param *params = &temp;
+
+	params->name = name;
+	params->flags = flags;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_MPIPE_OP_LINK_OPEN_AUX);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_link_open_aux);
+
+struct link_close_aux_param {
+	int mac;
+};
+
+int gxio_mpipe_link_close_aux(gxio_mpipe_context_t * context, int mac)
+{
+	struct link_close_aux_param temp;
+	struct link_close_aux_param *params = &temp;
+
+	params->mac = mac;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_MPIPE_OP_LINK_CLOSE_AUX);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_link_close_aux);
+
+
+struct get_timestamp_aux_param {
+	uint64_t sec;
+	uint64_t nsec;
+	uint64_t cycles;
+};
+
+int gxio_mpipe_get_timestamp_aux(gxio_mpipe_context_t * context, uint64_t * sec,
+				 uint64_t * nsec, uint64_t * cycles)
+{
+	int __result;
+	struct get_timestamp_aux_param temp;
+	struct get_timestamp_aux_param *params = &temp;
+
+	__result =
+	    hv_dev_pread(context->fd, 0, (HV_VirtAddr) params, sizeof(*params),
+			 GXIO_MPIPE_OP_GET_TIMESTAMP_AUX);
+	*sec = params->sec;
+	*nsec = params->nsec;
+	*cycles = params->cycles;
+
+	return __result;
+}
+
+EXPORT_SYMBOL(gxio_mpipe_get_timestamp_aux);
+
+struct set_timestamp_aux_param {
+	uint64_t sec;
+	uint64_t nsec;
+	uint64_t cycles;
+};
+
+int gxio_mpipe_set_timestamp_aux(gxio_mpipe_context_t * context, uint64_t sec,
+				 uint64_t nsec, uint64_t cycles)
+{
+	struct set_timestamp_aux_param temp;
+	struct set_timestamp_aux_param *params = &temp;
+
+	params->sec = sec;
+	params->nsec = nsec;
+	params->cycles = cycles;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_MPIPE_OP_SET_TIMESTAMP_AUX);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_set_timestamp_aux);
+
+struct adjust_timestamp_aux_param {
+	int64_t nsec;
+};
+
+int gxio_mpipe_adjust_timestamp_aux(gxio_mpipe_context_t * context,
+				    int64_t nsec)
+{
+	struct adjust_timestamp_aux_param temp;
+	struct adjust_timestamp_aux_param *params = &temp;
+
+	params->nsec = nsec;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params),
+			     GXIO_MPIPE_OP_ADJUST_TIMESTAMP_AUX);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_adjust_timestamp_aux);
+
+struct arm_pollfd_param {
+	union iorpc_pollfd pollfd;
+};
+
+int gxio_mpipe_arm_pollfd(gxio_mpipe_context_t * context, int pollfd_cookie)
+{
+	struct arm_pollfd_param temp;
+	struct arm_pollfd_param *params = &temp;
+
+	params->pollfd.kernel.cookie = pollfd_cookie;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_MPIPE_OP_ARM_POLLFD);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_arm_pollfd);
+
+struct close_pollfd_param {
+	union iorpc_pollfd pollfd;
+};
+
+int gxio_mpipe_close_pollfd(gxio_mpipe_context_t * context, int pollfd_cookie)
+{
+	struct close_pollfd_param temp;
+	struct close_pollfd_param *params = &temp;
+
+	params->pollfd.kernel.cookie = pollfd_cookie;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_MPIPE_OP_CLOSE_POLLFD);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_close_pollfd);
+
+struct get_mmio_base_param {
+	HV_PTE base;
+};
+
+int gxio_mpipe_get_mmio_base(gxio_mpipe_context_t * context, HV_PTE *base)
+{
+	int __result;
+	struct get_mmio_base_param temp;
+	struct get_mmio_base_param *params = &temp;
+
+	__result =
+	    hv_dev_pread(context->fd, 0, (HV_VirtAddr) params, sizeof(*params),
+			 GXIO_MPIPE_OP_GET_MMIO_BASE);
+	*base = params->base;
+
+	return __result;
+}
+
+EXPORT_SYMBOL(gxio_mpipe_get_mmio_base);
+
+struct check_mmio_offset_param {
+	unsigned long offset;
+	unsigned long size;
+};
+
+int gxio_mpipe_check_mmio_offset(gxio_mpipe_context_t * context,
+				 unsigned long offset, unsigned long size)
+{
+	struct check_mmio_offset_param temp;
+	struct check_mmio_offset_param *params = &temp;
+
+	params->offset = offset;
+	params->size = size;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_MPIPE_OP_CHECK_MMIO_OFFSET);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_check_mmio_offset);
diff --git a/arch/tile/gxio/iorpc_mpipe_info.c b/arch/tile/gxio/iorpc_mpipe_info.c
new file mode 100644
index 0000000..d0254aa
--- /dev/null
+++ b/arch/tile/gxio/iorpc_mpipe_info.c
@@ -0,0 +1,85 @@
+/*
+ * Copyright 2012 Tilera Corporation. All Rights Reserved.
+ *
+ *   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, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+/* This file is machine-generated; DO NOT EDIT! */
+#include "gxio/iorpc_mpipe_info.h"
+
+
+struct enumerate_aux_param {
+	_gxio_mpipe_link_name_t name;
+	_gxio_mpipe_link_mac_t mac;
+};
+
+int gxio_mpipe_info_enumerate_aux(gxio_mpipe_info_context_t * context,
+				  unsigned int idx,
+				  _gxio_mpipe_link_name_t * name,
+				  _gxio_mpipe_link_mac_t * mac)
+{
+	int __result;
+	struct enumerate_aux_param temp;
+	struct enumerate_aux_param *params = &temp;
+
+	__result =
+	    hv_dev_pread(context->fd, 0, (HV_VirtAddr) params, sizeof(*params),
+			 (((uint64_t) idx << 32) |
+			  GXIO_MPIPE_INFO_OP_ENUMERATE_AUX));
+	*name = params->name;
+	*mac = params->mac;
+
+	return __result;
+}
+
+EXPORT_SYMBOL(gxio_mpipe_info_enumerate_aux);
+
+struct get_mmio_base_param {
+	HV_PTE base;
+};
+
+int gxio_mpipe_info_get_mmio_base(gxio_mpipe_info_context_t * context,
+				  HV_PTE *base)
+{
+	int __result;
+	struct get_mmio_base_param temp;
+	struct get_mmio_base_param *params = &temp;
+
+	__result =
+	    hv_dev_pread(context->fd, 0, (HV_VirtAddr) params, sizeof(*params),
+			 GXIO_MPIPE_INFO_OP_GET_MMIO_BASE);
+	*base = params->base;
+
+	return __result;
+}
+
+EXPORT_SYMBOL(gxio_mpipe_info_get_mmio_base);
+
+struct check_mmio_offset_param {
+	unsigned long offset;
+	unsigned long size;
+};
+
+int gxio_mpipe_info_check_mmio_offset(gxio_mpipe_info_context_t * context,
+				      unsigned long offset, unsigned long size)
+{
+	struct check_mmio_offset_param temp;
+	struct check_mmio_offset_param *params = &temp;
+
+	params->offset = offset;
+	params->size = size;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params),
+			     GXIO_MPIPE_INFO_OP_CHECK_MMIO_OFFSET);
+}
+
+EXPORT_SYMBOL(gxio_mpipe_info_check_mmio_offset);
diff --git a/arch/tile/gxio/mpipe.c b/arch/tile/gxio/mpipe.c
new file mode 100644
index 0000000..e71c633
--- /dev/null
+++ b/arch/tile/gxio/mpipe.c
@@ -0,0 +1,545 @@
+/*
+ * Copyright 2012 Tilera Corporation. All Rights Reserved.
+ *
+ *   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, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+/*
+ * Implementation of mpipe gxio calls.
+ */
+
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/module.h>
+
+#include <gxio/iorpc_globals.h>
+#include <gxio/iorpc_mpipe.h>
+#include <gxio/iorpc_mpipe_info.h>
+#include <gxio/kiorpc.h>
+#include <gxio/mpipe.h>
+
+/* HACK: Avoid pointless "shadow" warnings. */
+#define link link_shadow
+
+int gxio_mpipe_init(gxio_mpipe_context_t *context, unsigned int mpipe_index)
+{
+	char file[32];
+
+	int fd;
+	int i;
+
+	snprintf(file, sizeof(file), "mpipe/%d/iorpc", mpipe_index);
+	fd = hv_dev_open((HV_VirtAddr) file, 0);
+	if (fd < 0) {
+		if (fd >= GXIO_ERR_MIN && fd <= GXIO_ERR_MAX)
+			return fd;
+		else
+			return -ENODEV;
+	}
+
+	context->fd = fd;
+
+	/* Map in the MMIO space. */
+	context->mmio_cfg_base = (void __force *)
+		iorpc_ioremap(fd, HV_MPIPE_CONFIG_MMIO_OFFSET,
+			      HV_MPIPE_CONFIG_MMIO_SIZE);
+	if (context->mmio_cfg_base == NULL)
+		goto cfg_failed;
+
+	context->mmio_fast_base = (void __force *)
+		iorpc_ioremap(fd, HV_MPIPE_FAST_MMIO_OFFSET,
+			      HV_MPIPE_FAST_MMIO_SIZE);
+	if (context->mmio_fast_base == NULL)
+		goto fast_failed;
+
+	/* Initialize the stacks. */
+	for (i = 0; i < 8; i++)
+		context->__stacks.stacks[i] = 255;
+
+	return 0;
+
+      fast_failed:
+	iounmap((void __force __iomem *)(context->mmio_cfg_base));
+      cfg_failed:
+	hv_dev_close(context->fd);
+	return -ENODEV;
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_init);
+
+int gxio_mpipe_destroy(gxio_mpipe_context_t *context)
+{
+	iounmap((void __force __iomem *)(context->mmio_cfg_base));
+	iounmap((void __force __iomem *)(context->mmio_fast_base));
+	return hv_dev_close(context->fd);
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_destroy);
+
+static int16_t gxio_mpipe_buffer_sizes[8] =
+	{ 128, 256, 512, 1024, 1664, 4096, 10368, 16384 };
+
+gxio_mpipe_buffer_size_enum_t gxio_mpipe_buffer_size_to_buffer_size_enum(size_t
+									 size)
+{
+	int i;
+	for (i = 0; i < 7; i++)
+		if (size <= gxio_mpipe_buffer_sizes[i])
+			break;
+	return i;
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_buffer_size_to_buffer_size_enum);
+
+size_t gxio_mpipe_buffer_size_enum_to_buffer_size(gxio_mpipe_buffer_size_enum_t
+						  buffer_size_enum)
+{
+	if (buffer_size_enum > 7)
+		buffer_size_enum = 7;
+
+	return gxio_mpipe_buffer_sizes[buffer_size_enum];
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_buffer_size_enum_to_buffer_size);
+
+size_t gxio_mpipe_calc_buffer_stack_bytes(unsigned long buffers)
+{
+	const int BUFFERS_PER_LINE = 12;
+
+	/* Count the number of cachlines. */
+	unsigned long lines =
+		(buffers + BUFFERS_PER_LINE - 1) / BUFFERS_PER_LINE;
+
+	/* Convert to bytes. */
+	return lines * CHIP_L2_LINE_SIZE();
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_calc_buffer_stack_bytes);
+
+int gxio_mpipe_init_buffer_stack(gxio_mpipe_context_t *context,
+				 unsigned int stack,
+				 gxio_mpipe_buffer_size_enum_t
+				 buffer_size_enum, void *mem, size_t mem_size,
+				 unsigned int mem_flags)
+{
+	int result;
+
+	memset(mem, 0, mem_size);
+
+	result = gxio_mpipe_init_buffer_stack_aux(context, mem, mem_size,
+						  mem_flags, stack,
+						  buffer_size_enum);
+	if (result < 0)
+		return result;
+
+	/* Save the stack. */
+	context->__stacks.stacks[buffer_size_enum] = stack;
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_init_buffer_stack);
+
+int gxio_mpipe_init_notif_ring(gxio_mpipe_context_t *context,
+			       unsigned int ring,
+			       void *mem, size_t mem_size,
+			       unsigned int mem_flags)
+{
+	return gxio_mpipe_init_notif_ring_aux(context, mem, mem_size,
+					      mem_flags, ring);
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_init_notif_ring);
+
+int gxio_mpipe_init_notif_group_and_buckets(gxio_mpipe_context_t *context,
+					    unsigned int group,
+					    unsigned int ring,
+					    unsigned int num_rings,
+					    unsigned int bucket,
+					    unsigned int num_buckets,
+					    gxio_mpipe_bucket_mode_t mode)
+{
+	int i;
+	int result;
+
+	gxio_mpipe_bucket_info_t bucket_info = { {
+						  .group = group,
+						  .mode = mode,
+						  }
+	};
+
+	gxio_mpipe_notif_group_bits_t bits = { {0} };
+
+	for (i = 0; i < num_rings; i++)
+		gxio_mpipe_notif_group_add_ring(&bits, ring + i);
+
+	result = gxio_mpipe_init_notif_group(context, group, bits);
+	if (result != 0)
+		return result;
+
+	for (i = 0; i < num_buckets; i++) {
+		bucket_info.notifring = ring + (i % num_rings);
+
+		result = gxio_mpipe_init_bucket(context, bucket + i,
+						bucket_info);
+		if (result != 0)
+			return result;
+	}
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_init_notif_group_and_buckets);
+
+int gxio_mpipe_init_edma_ring(gxio_mpipe_context_t *context,
+			      unsigned int ring, unsigned int channel,
+			      void *mem, size_t mem_size,
+			      unsigned int mem_flags)
+{
+	memset(mem, 0, mem_size);
+
+	return gxio_mpipe_init_edma_ring_aux(context, mem, mem_size, mem_flags,
+					     ring, channel);
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_init_edma_ring);
+
+void gxio_mpipe_rules_init(gxio_mpipe_rules_t *rules,
+			   gxio_mpipe_context_t *context)
+{
+	rules->context = context;
+	memset(&rules->list, 0, sizeof(rules->list));
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_rules_init);
+
+int gxio_mpipe_rules_begin(gxio_mpipe_rules_t *rules,
+			   unsigned int bucket, unsigned int num_buckets,
+			   gxio_mpipe_rules_stacks_t *stacks)
+{
+	int i;
+	int stack = 255;
+
+	gxio_mpipe_rules_list_t *list = &rules->list;
+
+	/* Current rule. */
+	gxio_mpipe_rules_rule_t *rule =
+		(gxio_mpipe_rules_rule_t *) (list->rules + list->head);
+
+	unsigned int head = list->tail;
+
+	/*
+	 * Align next rule properly.
+	 *Note that "dmacs_and_vlans" will also be aligned.
+	 */
+	unsigned int pad = 0;
+	while (((head + pad) % __alignof__(gxio_mpipe_rules_rule_t)) != 0)
+		pad++;
+
+	/*
+	 * Verify room.
+	 * ISSUE: Mark rules as broken on error?
+	 */
+	if (head + pad + sizeof(*rule) >= sizeof(list->rules))
+		return GXIO_MPIPE_ERR_RULES_FULL;
+
+	/* Verify num_buckets is a power of 2. */
+	if (__builtin_popcount(num_buckets) != 1)
+		return GXIO_MPIPE_ERR_RULES_INVALID;
+
+	/* Add padding to previous rule. */
+	rule->size += pad;
+
+	/* Start a new rule. */
+	list->head = head + pad;
+
+	rule = (gxio_mpipe_rules_rule_t *) (list->rules + list->head);
+
+	/* Default some values. */
+	rule->headroom = 2;
+	rule->tailroom = 0;
+	rule->capacity = 16384;
+
+	/* Save the bucket info. */
+	rule->bucket_mask = num_buckets - 1;
+	rule->bucket_first = bucket;
+
+	for (i = 8 - 1; i >= 0; i--) {
+		int maybe =
+			stacks ? stacks->stacks[i] : rules->context->__stacks.
+			stacks[i];
+		if (maybe != 255)
+			stack = maybe;
+		rule->stacks.stacks[i] = stack;
+	}
+
+	if (stack == 255)
+		return GXIO_MPIPE_ERR_RULES_INVALID;
+
+	/* NOTE: Only entries at the end of the array can be 255. */
+	for (i = 8 - 1; i > 0; i--) {
+		if (rule->stacks.stacks[i] == 255) {
+			rule->stacks.stacks[i] = stack;
+			rule->capacity =
+				gxio_mpipe_buffer_size_enum_to_buffer_size(i -
+									   1);
+		}
+	}
+
+	rule->size = sizeof(*rule);
+	list->tail = list->head + rule->size;
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_rules_begin);
+
+int gxio_mpipe_rules_add_channel(gxio_mpipe_rules_t *rules,
+				 unsigned int channel)
+{
+	gxio_mpipe_rules_list_t *list = &rules->list;
+
+	gxio_mpipe_rules_rule_t *rule =
+		(gxio_mpipe_rules_rule_t *) (list->rules + list->head);
+
+	/* Verify channel. */
+	if (channel >= 32)
+		return GXIO_MPIPE_ERR_RULES_INVALID;
+
+	/* Verify begun. */
+	if (list->tail == 0)
+		return GXIO_MPIPE_ERR_RULES_EMPTY;
+
+	rule->channel_bits |= (1UL << channel);
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_rules_add_channel);
+
+int gxio_mpipe_rules_set_headroom(gxio_mpipe_rules_t *rules, uint8_t headroom)
+{
+	gxio_mpipe_rules_list_t *list = &rules->list;
+
+	gxio_mpipe_rules_rule_t *rule =
+		(gxio_mpipe_rules_rule_t *) (list->rules + list->head);
+
+	/* Verify begun. */
+	if (list->tail == 0)
+		return GXIO_MPIPE_ERR_RULES_EMPTY;
+
+	rule->headroom = headroom;
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_rules_set_headroom);
+
+int gxio_mpipe_rules_commit(gxio_mpipe_rules_t *rules)
+{
+	gxio_mpipe_rules_list_t *list = &rules->list;
+	unsigned int size =
+		offsetof(gxio_mpipe_rules_list_t, rules) + list->tail;
+	return gxio_mpipe_commit_rules(rules->context, list, size);
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_rules_commit);
+
+int gxio_mpipe_iqueue_init(gxio_mpipe_iqueue_t *iqueue,
+			   gxio_mpipe_context_t *context,
+			   unsigned int ring,
+			   void *mem, size_t mem_size, unsigned int mem_flags)
+{
+	/* The init call below will verify that "mem_size" is legal. */
+	unsigned int num_entries = mem_size / sizeof(gxio_mpipe_idesc_t);
+
+	iqueue->context = context;
+	iqueue->idescs = (gxio_mpipe_idesc_t *)mem;
+	iqueue->ring = ring;
+	iqueue->num_entries = num_entries;
+	iqueue->mask_num_entries = num_entries - 1;
+	iqueue->log2_num_entries = __builtin_ctz(num_entries);
+	iqueue->head = 1;
+#ifdef __BIG_ENDIAN__
+	iqueue->swapped = 0;
+#endif
+
+	/* Initialize the "tail". */
+	__gxio_mmio_write(mem, iqueue->head);
+
+	return gxio_mpipe_init_notif_ring(context, ring, mem, mem_size,
+					  mem_flags);
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_iqueue_init);
+
+int gxio_mpipe_equeue_init(gxio_mpipe_equeue_t *equeue,
+			   gxio_mpipe_context_t *context,
+			   unsigned int edma_ring_id,
+			   unsigned int channel,
+			   void *mem, unsigned int mem_size,
+			   unsigned int mem_flags)
+{
+	/* The init call below will verify that "mem_size" is legal. */
+	unsigned int num_entries = mem_size / sizeof(gxio_mpipe_edesc_t);
+
+	/* Offset used to read number of completed commands. */
+	MPIPE_EDMA_POST_REGION_ADDR_t offset;
+
+	int result = gxio_mpipe_init_edma_ring(context, edma_ring_id, channel,
+					       mem, mem_size, mem_flags);
+	if (result < 0)
+		return result;
+
+	memset(equeue, 0, sizeof(*equeue));
+
+	offset.word = 0;
+	offset.region =
+		MPIPE_MMIO_ADDR__REGION_VAL_EDMA -
+		MPIPE_MMIO_ADDR__REGION_VAL_IDMA;
+	offset.ring = edma_ring_id;
+
+	__gxio_dma_queue_init(&equeue->dma_queue,
+			      context->mmio_fast_base + offset.word,
+			      num_entries);
+	equeue->edescs = mem;
+	equeue->mask_num_entries = num_entries - 1;
+	equeue->log2_num_entries = __builtin_ctz(num_entries);
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_equeue_init);
+
+int gxio_mpipe_set_timestamp(gxio_mpipe_context_t *context,
+			     const struct timespec *ts)
+{
+	cycles_t cycles = get_cycles();
+	return gxio_mpipe_set_timestamp_aux(context, (uint64_t)ts->tv_sec,
+					    (uint64_t)ts->tv_nsec,
+					    (uint64_t)cycles);
+}
+
+int gxio_mpipe_get_timestamp(gxio_mpipe_context_t *context,
+			     struct timespec *ts)
+{
+	int ret;
+	cycles_t cycles_prev, cycles_now, clock_rate;
+	cycles_prev = get_cycles();
+	ret = gxio_mpipe_get_timestamp_aux(context, (uint64_t *)&ts->tv_sec,
+					   (uint64_t *)&ts->tv_nsec,
+					   (uint64_t *)&cycles_now);
+	if (ret < 0) {
+		return ret;
+	}
+
+	clock_rate = get_clock_rate();
+	ts->tv_nsec -= (cycles_now - cycles_prev) * 1000000000LL / clock_rate;
+	if (ts->tv_nsec < 0) {
+		ts->tv_nsec += 1000000000LL;
+		ts->tv_sec -= 1;
+	}
+	return ret;
+}
+
+int gxio_mpipe_adjust_timestamp(gxio_mpipe_context_t *context, int64_t delta)
+{
+	return gxio_mpipe_adjust_timestamp_aux(context, delta);
+}
+
+/* Get our internal context used for link name access.  This context is
+ *  special in that it is not associated with an mPIPE service domain.
+ */
+static gxio_mpipe_context_t *_gxio_get_link_context(void)
+{
+	static gxio_mpipe_context_t context;
+	static gxio_mpipe_context_t *contextp;
+	static int tried_open = 0;
+	static DEFINE_MUTEX(mutex);
+
+	mutex_lock(&mutex);
+
+	if (!tried_open) {
+		int i = 0;
+		tried_open = 1;
+
+		/*
+		 * "4" here is the maximum possible number of mPIPE shims; it's
+		 * an exaggeration but we shouldn't ever go beyond 2 anyway.
+		 */
+		for (i = 0; i < 4; i++) {
+			char file[80];
+
+			snprintf(file, sizeof(file), "mpipe/%d/iorpc_info", i);
+			context.fd = hv_dev_open((HV_VirtAddr) file, 0);
+			if (context.fd < 0)
+				continue;
+
+			contextp = &context;
+			break;
+		}
+	}
+
+	mutex_unlock(&mutex);
+
+	return contextp;
+}
+
+int gxio_mpipe_link_enumerate_mac(int idx, char *link_name, uint8_t *link_mac)
+{
+	int rv;
+	_gxio_mpipe_link_name_t name;
+	_gxio_mpipe_link_mac_t mac;
+
+	gxio_mpipe_context_t *context = _gxio_get_link_context();
+	if (!context)
+		return GXIO_ERR_NO_DEVICE;
+
+	rv = gxio_mpipe_info_enumerate_aux(context, idx, &name, &mac);
+	if (rv >= 0) {
+		strncpy(link_name, name.name, sizeof(name.name));
+		memcpy(link_mac, mac.mac, sizeof(mac.mac));
+	}
+
+	return rv;
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_link_enumerate_mac);
+
+int gxio_mpipe_link_open(gxio_mpipe_link_t *link,
+			 gxio_mpipe_context_t *context, const char *link_name,
+			 unsigned int flags)
+{
+	_gxio_mpipe_link_name_t name;
+	int rv;
+
+	strncpy(name.name, link_name, sizeof(name.name));
+	name.name[GXIO_MPIPE_LINK_NAME_LEN - 1] = '\0';
+
+	rv = gxio_mpipe_link_open_aux(context, name, flags);
+	if (rv < 0)
+		return rv;
+
+	link->context = context;
+	link->channel = rv >> 8;
+	link->mac = rv & 0xFF;
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_link_open);
+
+int gxio_mpipe_link_close(gxio_mpipe_link_t *link)
+{
+	return gxio_mpipe_link_close_aux(link->context, link->mac);
+}
+
+EXPORT_SYMBOL_GPL(gxio_mpipe_link_close);