diff --git a/arch/arm/include/asm/arch-tegra/ivc.h b/arch/arm/include/asm/arch-tegra/ivc.h
new file mode 100644
index 0000000000000000000000000000000000000000..7f2287ae28022f92a0e95ccc8c8ae605ea58be5c
--- /dev/null
+++ b/arch/arm/include/asm/arch-tegra/ivc.h
@@ -0,0 +1,179 @@
+/*
+ * Copyright (c) 2016, NVIDIA CORPORATION.
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+#ifndef _ASM_ARCH_TEGRA_IVC_H
+#define _ASM_ARCH_TEGRA_IVC_H
+
+#include <common.h>
+
+/*
+ * Tegra IVC is a communication protocol that transfers fixed-size frames
+ * bi-directionally and in-order between the local CPU and some remote entity.
+ * Communication is via a statically sized and allocated buffer in shared
+ * memory and a notification mechanism.
+ *
+ * This API handles all aspects of the shared memory buffer's metadata, and
+ * leaves all aspects of the frame content to the calling code; frames
+ * typically contain some higher-level protocol. The notification mechanism is
+ * also handled externally to this API, since it can vary from instance to
+ * instance.
+ *
+ * The client model is to first find some free (for TX) or filled (for RX)
+ * frame, process that frame's memory buffer (fill or read it), and then
+ * inform the protocol that the frame has been filled/read, i.e. advance the
+ * write/read pointer. If the channel is full, there may be no available frames
+ * to fill/read. In this case, client code may either poll for an available
+ * frame, or wait for the remote entity to send a notification to the local
+ * CPU.
+ */
+
+/**
+ * struct tegra_ivc - In-memory shared memory layout.
+ *
+ * This is described in detail in ivc.c.
+ */
+struct tegra_ivc_channel_header;
+
+/**
+ * struct tegra_ivc - Software state of an IVC channel.
+ *
+ * This state is internal to the IVC code and should not be accessed directly
+ * by clients. It is public solely so clients can allocate storage for the
+ * structure.
+ */
+struct tegra_ivc {
+ /**
+ * rx_channel - Pointer to the shared memory region used to receive
+ * messages from the remote entity.
+ */
+ struct tegra_ivc_channel_header *rx_channel;
+ /**
+ * tx_channel - Pointer to the shared memory region used to send
+ * messages to the remote entity.
+ */
+ struct tegra_ivc_channel_header *tx_channel;
+ /**
+ * r_pos - The position in list of frames in rx_channel that we are
+ * reading from.
+ */
+ uint32_t r_pos;
+ /**
+ * w_pos - The position in list of frames in tx_channel that we are
+ * writing to.
+ */
+ uint32_t w_pos;
+ /**
+ * nframes - The number of frames allocated (in each direction) in
+ * shared memory.
+ */
+ uint32_t nframes;
+ /**
+ * frame_size - The size of each frame in shared memory.
+ */
+ uint32_t frame_size;
+ /**
+ * notify - Function to call to notify the remote processor of a
+ * change in channel state.
+ */
+ void (*notify)(struct tegra_ivc *);
+};
+
+/**
+ * tegra_ivc_read_get_next_frame - Locate the next frame to receive.
+ *
+ * Locate the next frame to be received/processed, return the address of the
+ * frame, and do not remove it from the queue. Repeated calls to this function
+ * will return the same address until tegra_ivc_read_advance() is called.
+ *
+ * @ivc The IVC channel.
+ * @frame Pointer to be filled with the address of the frame to receive.
+ *
+ * @return 0 if a frame is available, else a negative error code.
+ */
+int tegra_ivc_read_get_next_frame(struct tegra_ivc *ivc, void **frame);
+
+/**
+ * tegra_ivc_read_advance - Advance the read queue.
+ *
+ * Inform the protocol and remote entity that the frame returned by
+ * tegra_ivc_read_get_next_frame() has been processed. The remote end may then
+ * re-use it to transmit further data. Subsequent to this function returning,
+ * tegra_ivc_read_get_next_frame() will return a different frame.
+ *
+ * @ivc The IVC channel.
+ *
+ * @return 0 if OK, else a negative error code.
+ */
+int tegra_ivc_read_advance(struct tegra_ivc *ivc);
+
+/**
+ * tegra_ivc_write_get_next_frame - Locate the next frame to fill for transmit.
+ *
+ * Locate the next frame to be filled for transmit, return the address of the
+ * frame, and do not add it to the queue. Repeated calls to this function
+ * will return the same address until tegra_ivc_read_advance() is called.
+ *
+ * @ivc The IVC channel.
+ * @frame Pointer to be filled with the address of the frame to fill.
+ *
+ * @return 0 if a frame is available, else a negative error code.
+ */
+int tegra_ivc_write_get_next_frame(struct tegra_ivc *ivc, void **frame);
+
+/**
+ * tegra_ivc_write_advance - Advance the write queue.
+ *
+ * Inform the protocol and remote entity that the frame returned by
+ * tegra_ivc_write_get_next_frame() has been filled and should be transmitted.
+ * The remote end may then read data from it. Subsequent to this function
+ * returning, tegra_ivc_write_get_next_frame() will return a different frame.
+ *
+ * @ivc The IVC channel.
+ *
+ * @return 0 if OK, else a negative error code.
+ */
+int tegra_ivc_write_advance(struct tegra_ivc *ivc);
+
+/**
+ * tegra_ivc_channel_notified - handle internal messages
+ *
+ * This function must be called following every notification.
+ *
+ * @ivc The IVC channel.
+ *
+ * @return 0 if the channel is ready for communication, or -EAGAIN if a
+ * channel reset is in progress.
+ */
+int tegra_ivc_channel_notified(struct tegra_ivc *ivc);
+
+/**
+ * tegra_ivc_channel_reset - initiates a reset of the shared memory state
+ *
+ * This function must be called after a channel is initialized but before it
+ * is used for communication. The channel will be ready for use when a
+ * subsequent call to notify the remote of the channel reset indicates the
+ * reset operation is complete.
+ *
+ * @ivc The IVC channel.
+ */
+void tegra_ivc_channel_reset(struct tegra_ivc *ivc);
+
+/**
+ * tegra_ivc_init - Initialize a channel's software state.
+ *
+ * @ivc The IVC channel.
+ * @rx_base Address of the the RX shared memory buffer.
+ * @tx_base Address of the the TX shared memory buffer.
+ * @nframes Number of frames in each shared memory buffer.
+ * @frame_size Size of each frame.
+ *
+ * @return 0 if OK, else a negative error code.
+ */
+int tegra_ivc_init(struct tegra_ivc *ivc, ulong rx_base, ulong tx_base,
+ uint32_t nframes, uint32_t frame_size,
+ void (*notify)(struct tegra_ivc *));
+
+#endif
diff --git a/arch/arm/mach-tegra/Kconfig b/arch/arm/mach-tegra/Kconfig
index f4affa5512bcf8c5f78a75a8e0c7b020d1674821..85ae3b7f420992c2a125fc7c981c87fb6f4cf6a0 100644
--- a/arch/arm/mach-tegra/Kconfig
+++ b/arch/arm/mach-tegra/Kconfig
@@ -1,5 +1,13 @@
if TEGRA
+config TEGRA_IVC
+ bool "Tegra IVC protocol"
+ help
+ IVC (Inter-VM Communication) protocol is a Tegra-specific IPC
+ (Inter Processor Communication) framework. Within the context of
+ U-Boot, it is typically used for communication between the main CPU
+ and various auxiliary processors.
+
config TEGRA_COMMON
bool "Tegra common options"
select DM
@@ -60,6 +68,7 @@ config TEGRA186
select TEGRA186_GPIO
select TEGRA_ARMV8_COMMON
select TEGRA_HSP
+ select TEGRA_IVC
endchoice
diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile
index 3b8d0127c7aa2dbfef3364191171e3ae22287ca6..d0bf5a6e75ef2dc178bf612d85565a66b05eef0e 100644
--- a/arch/arm/mach-tegra/Makefile
+++ b/arch/arm/mach-tegra/Makefile
@@ -27,6 +27,7 @@ endif
obj-$(CONFIG_ARM64) += arm64-mmu.o
obj-$(CONFIG_TEGRA_CLOCK_SCALING) += emc.o
obj-$(CONFIG_TEGRA_GPU) += gpu.o
+obj-$(CONFIG_TEGRA_IVC) += ivc.o
obj-y += lowlevel_init.o
ifndef CONFIG_SPL_BUILD
obj-$(CONFIG_ARMV7_PSCI) += psci.o
diff --git a/arch/arm/mach-tegra/ivc.c b/arch/arm/mach-tegra/ivc.c
new file mode 100644
index 0000000000000000000000000000000000000000..cf6626fb12c7d60983ca8600d9d7e865c8a123f9
--- /dev/null
+++ b/arch/arm/mach-tegra/ivc.c
@@ -0,0 +1,553 @@
+/*
+ * Copyright (c) 2016, NVIDIA CORPORATION.
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch-tegra/ivc.h>
+
+#define TEGRA_IVC_ALIGN 64
+
+/*
+ * IVC channel reset protocol.
+ *
+ * Each end uses its tx_channel.state to indicate its synchronization state.
+ */
+enum ivc_state {
+ /*
+ * This value is zero for backwards compatibility with services that
+ * assume channels to be initially zeroed. Such channels are in an
+ * initially valid state, but cannot be asynchronously reset, and must
+ * maintain a valid state at all times.
+ *
+ * The transmitting end can enter the established state from the sync or
+ * ack state when it observes the receiving endpoint in the ack or
+ * established state, indicating that has cleared the counters in our
+ * rx_channel.
+ */
+ ivc_state_established = 0,
+
+ /*
+ * If an endpoint is observed in the sync state, the remote endpoint is
+ * allowed to clear the counters it owns asynchronously with respect to
+ * the current endpoint. Therefore, the current endpoint is no longer
+ * allowed to communicate.
+ */
+ ivc_state_sync,
+
+ /*
+ * When the transmitting end observes the receiving end in the sync
+ * state, it can clear the w_count and r_count and transition to the ack
+ * state. If the remote endpoint observes us in the ack state, it can
+ * return to the established state once it has cleared its counters.
+ */
+ ivc_state_ack
+};
+
+/*
+ * This structure is divided into two-cache aligned parts, the first is only
+ * written through the tx_channel pointer, while the second is only written
+ * through the rx_channel pointer. This delineates ownership of the cache lines,
+ * which is critical to performance and necessary in non-cache coherent
+ * implementations.
+ */
+struct tegra_ivc_channel_header {
+ union {
+ /* fields owned by the transmitting end */
+ struct {
+ uint32_t w_count;
+ uint32_t state;
+ };
+ uint8_t w_align[TEGRA_IVC_ALIGN];
+ };
+ union {
+ /* fields owned by the receiving end */
+ uint32_t r_count;
+ uint8_t r_align[TEGRA_IVC_ALIGN];
+ };
+};
+
+static inline void tegra_ivc_invalidate_counter(struct tegra_ivc *ivc,
+ struct tegra_ivc_channel_header *h,
+ ulong offset)
+{
+ ulong base = ((ulong)h) + offset;
+ invalidate_dcache_range(base, base + TEGRA_IVC_ALIGN);
+}
+
+static inline void tegra_ivc_flush_counter(struct tegra_ivc *ivc,
+ struct tegra_ivc_channel_header *h,
+ ulong offset)
+{
+ ulong base = ((ulong)h) + offset;
+ flush_dcache_range(base, base + TEGRA_IVC_ALIGN);
+}
+
+static inline ulong tegra_ivc_frame_addr(struct tegra_ivc *ivc,
+ struct tegra_ivc_channel_header *h,
+ uint32_t frame)
+{
+ BUG_ON(frame >= ivc->nframes);
+
+ return ((ulong)h) + sizeof(struct tegra_ivc_channel_header) +
+ (ivc->frame_size * frame);
+}
+
+static inline void *tegra_ivc_frame_pointer(struct tegra_ivc *ivc,
+ struct tegra_ivc_channel_header *ch,
+ uint32_t frame)
+{
+ return (void *)tegra_ivc_frame_addr(ivc, ch, frame);
+}
+
+static inline void tegra_ivc_invalidate_frame(struct tegra_ivc *ivc,
+ struct tegra_ivc_channel_header *h,
+ unsigned frame)
+{
+ ulong base = tegra_ivc_frame_addr(ivc, h, frame);
+ invalidate_dcache_range(base, base + ivc->frame_size);
+}
+
+static inline void tegra_ivc_flush_frame(struct tegra_ivc *ivc,
+ struct tegra_ivc_channel_header *h,
+ unsigned frame)
+{
+ ulong base = tegra_ivc_frame_addr(ivc, h, frame);
+ flush_dcache_range(base, base + ivc->frame_size);
+}
+
+static inline int tegra_ivc_channel_empty(struct tegra_ivc *ivc,
+ struct tegra_ivc_channel_header *ch)
+{
+ /*
+ * This function performs multiple checks on the same values with
+ * security implications, so create snapshots with ACCESS_ONCE() to
+ * ensure that these checks use the same values.
+ */
+ uint32_t w_count = ACCESS_ONCE(ch->w_count);
+ uint32_t r_count = ACCESS_ONCE(ch->r_count);
+
+ /*
+ * Perform an over-full check to prevent denial of service attacks where
+ * a server could be easily fooled into believing that there's an
+ * extremely large number of frames ready, since receivers are not
+ * expected to check for full or over-full conditions.
+ *
+ * Although the channel isn't empty, this is an invalid case caused by
+ * a potentially malicious peer, so returning empty is safer, because it
+ * gives the impression that the channel has gone silent.
+ */
+ if (w_count - r_count > ivc->nframes)
+ return 1;
+
+ return w_count == r_count;
+}
+
+static inline int tegra_ivc_channel_full(struct tegra_ivc *ivc,
+ struct tegra_ivc_channel_header *ch)
+{
+ /*
+ * Invalid cases where the counters indicate that the queue is over
+ * capacity also appear full.
+ */
+ return (ACCESS_ONCE(ch->w_count) - ACCESS_ONCE(ch->r_count)) >=
+ ivc->nframes;
+}
+
+static inline void tegra_ivc_advance_rx(struct tegra_ivc *ivc)
+{
+ ACCESS_ONCE(ivc->rx_channel->r_count) =
+ ACCESS_ONCE(ivc->rx_channel->r_count) + 1;
+
+ if (ivc->r_pos == ivc->nframes - 1)
+ ivc->r_pos = 0;
+ else
+ ivc->r_pos++;
+}
+
+static inline void tegra_ivc_advance_tx(struct tegra_ivc *ivc)
+{
+ ACCESS_ONCE(ivc->tx_channel->w_count) =
+ ACCESS_ONCE(ivc->tx_channel->w_count) + 1;
+
+ if (ivc->w_pos == ivc->nframes - 1)
+ ivc->w_pos = 0;
+ else
+ ivc->w_pos++;
+}
+
+static inline int tegra_ivc_check_read(struct tegra_ivc *ivc)
+{
+ ulong offset;
+
+ /*
+ * tx_channel->state is set locally, so it is not synchronized with
+ * state from the remote peer. The remote peer cannot reset its
+ * transmit counters until we've acknowledged its synchronization
+ * request, so no additional synchronization is required because an
+ * asynchronous transition of rx_channel->state to ivc_state_ack is not
+ * allowed.
+ */
+ if (ivc->tx_channel->state != ivc_state_established)
+ return -ECONNRESET;
+
+ /*
+ * Avoid unnecessary invalidations when performing repeated accesses to
+ * an IVC channel by checking the old queue pointers first.
+ * Synchronization is only necessary when these pointers indicate empty
+ * or full.
+ */
+ if (!tegra_ivc_channel_empty(ivc, ivc->rx_channel))
+ return 0;
+
+ offset = offsetof(struct tegra_ivc_channel_header, w_count);
+ tegra_ivc_invalidate_counter(ivc, ivc->rx_channel, offset);
+ return tegra_ivc_channel_empty(ivc, ivc->rx_channel) ? -ENOMEM : 0;
+}
+
+static inline int tegra_ivc_check_write(struct tegra_ivc *ivc)
+{
+ ulong offset;
+
+ if (ivc->tx_channel->state != ivc_state_established)
+ return -ECONNRESET;
+
+ if (!tegra_ivc_channel_full(ivc, ivc->tx_channel))
+ return 0;
+
+ offset = offsetof(struct tegra_ivc_channel_header, r_count);
+ tegra_ivc_invalidate_counter(ivc, ivc->tx_channel, offset);
+ return tegra_ivc_channel_full(ivc, ivc->tx_channel) ? -ENOMEM : 0;
+}
+
+static inline uint32_t tegra_ivc_channel_avail_count(struct tegra_ivc *ivc,
+ struct tegra_ivc_channel_header *ch)
+{
+ /*
+ * This function isn't expected to be used in scenarios where an
+ * over-full situation can lead to denial of service attacks. See the
+ * comment in tegra_ivc_channel_empty() for an explanation about
+ * special over-full considerations.
+ */
+ return ACCESS_ONCE(ch->w_count) - ACCESS_ONCE(ch->r_count);
+}
+
+int tegra_ivc_read_get_next_frame(struct tegra_ivc *ivc, void **frame)
+{
+ int result = tegra_ivc_check_read(ivc);
+ if (result < 0)
+ return result;
+
+ /*
+ * Order observation of w_pos potentially indicating new data before
+ * data read.
+ */
+ mb();
+
+ tegra_ivc_invalidate_frame(ivc, ivc->rx_channel, ivc->r_pos);
+ *frame = tegra_ivc_frame_pointer(ivc, ivc->rx_channel, ivc->r_pos);
+
+ return 0;
+}
+
+int tegra_ivc_read_advance(struct tegra_ivc *ivc)
+{
+ ulong offset;
+ int result;
+
+ /*
+ * No read barriers or synchronization here: the caller is expected to
+ * have already observed the channel non-empty. This check is just to
+ * catch programming errors.
+ */
+ result = tegra_ivc_check_read(ivc);
+ if (result)
+ return result;
+
+ tegra_ivc_advance_rx(ivc);
+ offset = offsetof(struct tegra_ivc_channel_header, r_count);
+ tegra_ivc_flush_counter(ivc, ivc->rx_channel, offset);
+
+ /*
+ * Ensure our write to r_pos occurs before our read from w_pos.
+ */
+ mb();
+
+ offset = offsetof(struct tegra_ivc_channel_header, w_count);
+ tegra_ivc_invalidate_counter(ivc, ivc->rx_channel, offset);
+
+ if (tegra_ivc_channel_avail_count(ivc, ivc->rx_channel) ==
+ ivc->nframes - 1)
+ ivc->notify(ivc);
+
+ return 0;
+}
+
+int tegra_ivc_write_get_next_frame(struct tegra_ivc *ivc, void **frame)
+{
+ int result = tegra_ivc_check_write(ivc);
+ if (result)
+ return result;
+
+ *frame = tegra_ivc_frame_pointer(ivc, ivc->tx_channel, ivc->w_pos);
+
+ return 0;
+}
+
+int tegra_ivc_write_advance(struct tegra_ivc *ivc)
+{
+ ulong offset;
+ int result;
+
+ result = tegra_ivc_check_write(ivc);
+ if (result)
+ return result;
+
+ tegra_ivc_flush_frame(ivc, ivc->tx_channel, ivc->w_pos);
+
+ /*
+ * Order any possible stores to the frame before update of w_pos.
+ */
+ mb();
+
+ tegra_ivc_advance_tx(ivc);
+ offset = offsetof(struct tegra_ivc_channel_header, w_count);
+ tegra_ivc_flush_counter(ivc, ivc->tx_channel, offset);
+
+ /*
+ * Ensure our write to w_pos occurs before our read from r_pos.
+ */
+ mb();
+
+ offset = offsetof(struct tegra_ivc_channel_header, r_count);
+ tegra_ivc_invalidate_counter(ivc, ivc->tx_channel, offset);
+
+ if (tegra_ivc_channel_avail_count(ivc, ivc->tx_channel) == 1)
+ ivc->notify(ivc);
+
+ return 0;
+}
+
+/*
+ * ===============================================================
+ * IVC State Transition Table - see tegra_ivc_channel_notified()
+ * ===============================================================
+ *
+ * local remote action
+ * ----- ------ -----------------------------------
+ * SYNC EST <none>
+ * SYNC ACK reset counters; move to EST; notify
+ * SYNC SYNC reset counters; move to ACK; notify
+ * ACK EST move to EST; notify
+ * ACK ACK move to EST; notify
+ * ACK SYNC reset counters; move to ACK; notify
+ * EST EST <none>
+ * EST ACK <none>
+ * EST SYNC reset counters; move to ACK; notify
+ *
+ * ===============================================================
+ */
+int tegra_ivc_channel_notified(struct tegra_ivc *ivc)
+{
+ ulong offset;
+ enum ivc_state peer_state;
+
+ /* Copy the receiver's state out of shared memory. */
+ offset = offsetof(struct tegra_ivc_channel_header, w_count);
+ tegra_ivc_invalidate_counter(ivc, ivc->rx_channel, offset);
+ peer_state = ACCESS_ONCE(ivc->rx_channel->state);
+
+ if (peer_state == ivc_state_sync) {
+ /*
+ * Order observation of ivc_state_sync before stores clearing
+ * tx_channel.
+ */
+ mb();
+
+ /*
+ * Reset tx_channel counters. The remote end is in the SYNC
+ * state and won't make progress until we change our state,
+ * so the counters are not in use at this time.
+ */
+ ivc->tx_channel->w_count = 0;
+ ivc->rx_channel->r_count = 0;
+
+ ivc->w_pos = 0;
+ ivc->r_pos = 0;
+
+ /*
+ * Ensure that counters appear cleared before new state can be
+ * observed.
+ */
+ mb();
+
+ /*
+ * Move to ACK state. We have just cleared our counters, so it
+ * is now safe for the remote end to start using these values.
+ */
+ ivc->tx_channel->state = ivc_state_ack;
+ offset = offsetof(struct tegra_ivc_channel_header, w_count);
+ tegra_ivc_flush_counter(ivc, ivc->tx_channel, offset);
+
+ /*
+ * Notify remote end to observe state transition.
+ */
+ ivc->notify(ivc);
+ } else if (ivc->tx_channel->state == ivc_state_sync &&
+ peer_state == ivc_state_ack) {
+ /*
+ * Order observation of ivc_state_sync before stores clearing
+ * tx_channel.
+ */
+ mb();
+
+ /*
+ * Reset tx_channel counters. The remote end is in the ACK
+ * state and won't make progress until we change our state,
+ * so the counters are not in use at this time.
+ */
+ ivc->tx_channel->w_count = 0;
+ ivc->rx_channel->r_count = 0;
+
+ ivc->w_pos = 0;
+ ivc->r_pos = 0;
+
+ /*
+ * Ensure that counters appear cleared before new state can be
+ * observed.
+ */
+ mb();
+
+ /*
+ * Move to ESTABLISHED state. We know that the remote end has
+ * already cleared its counters, so it is safe to start
+ * writing/reading on this channel.
+ */
+ ivc->tx_channel->state = ivc_state_established;
+ offset = offsetof(struct tegra_ivc_channel_header, w_count);
+ tegra_ivc_flush_counter(ivc, ivc->tx_channel, offset);
+
+ /*
+ * Notify remote end to observe state transition.
+ */
+ ivc->notify(ivc);
+ } else if (ivc->tx_channel->state == ivc_state_ack) {
+ /*
+ * At this point, we have observed the peer to be in either
+ * the ACK or ESTABLISHED state. Next, order observation of
+ * peer state before storing to tx_channel.
+ */
+ mb();
+
+ /*
+ * Move to ESTABLISHED state. We know that we have previously
+ * cleared our counters, and we know that the remote end has
+ * cleared its counters, so it is safe to start writing/reading
+ * on this channel.
+ */
+ ivc->tx_channel->state = ivc_state_established;
+ offset = offsetof(struct tegra_ivc_channel_header, w_count);
+ tegra_ivc_flush_counter(ivc, ivc->tx_channel, offset);
+
+ /*
+ * Notify remote end to observe state transition.
+ */
+ ivc->notify(ivc);
+ } else {
+ /*
+ * There is no need to handle any further action. Either the
+ * channel is already fully established, or we are waiting for
+ * the remote end to catch up with our current state. Refer
+ * to the diagram in "IVC State Transition Table" above.
+ */
+ }
+
+ if (ivc->tx_channel->state != ivc_state_established)
+ return -EAGAIN;
+
+ return 0;
+}
+
+void tegra_ivc_channel_reset(struct tegra_ivc *ivc)
+{
+ ulong offset;
+
+ ivc->tx_channel->state = ivc_state_sync;
+ offset = offsetof(struct tegra_ivc_channel_header, w_count);
+ tegra_ivc_flush_counter(ivc, ivc->tx_channel, offset);
+ ivc->notify(ivc);
+}
+
+static int check_ivc_params(ulong qbase1, ulong qbase2, uint32_t nframes,
+ uint32_t frame_size)
+{
+ int ret = 0;
+
+ BUG_ON(offsetof(struct tegra_ivc_channel_header, w_count) &
+ (TEGRA_IVC_ALIGN - 1));
+ BUG_ON(offsetof(struct tegra_ivc_channel_header, r_count) &
+ (TEGRA_IVC_ALIGN - 1));
+ BUG_ON(sizeof(struct tegra_ivc_channel_header) &
+ (TEGRA_IVC_ALIGN - 1));
+
+ if ((uint64_t)nframes * (uint64_t)frame_size >= 0x100000000) {
+ error("tegra_ivc: nframes * frame_size overflows\n");
+ return -EINVAL;
+ }
+
+ /*
+ * The headers must at least be aligned enough for counters
+ * to be accessed atomically.
+ */
+ if ((qbase1 & (TEGRA_IVC_ALIGN - 1)) ||
+ (qbase2 & (TEGRA_IVC_ALIGN - 1))) {
+ error("tegra_ivc: channel start not aligned\n");
+ return -EINVAL;
+ }
+
+ if (frame_size & (TEGRA_IVC_ALIGN - 1)) {
+ error("tegra_ivc: frame size not adequately aligned\n");
+ return -EINVAL;
+ }
+
+ if (qbase1 < qbase2) {
+ if (qbase1 + frame_size * nframes > qbase2)
+ ret = -EINVAL;
+ } else {
+ if (qbase2 + frame_size * nframes > qbase1)
+ ret = -EINVAL;
+ }
+
+ if (ret) {
+ error("tegra_ivc: queue regions overlap\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+int tegra_ivc_init(struct tegra_ivc *ivc, ulong rx_base, ulong tx_base,
+ uint32_t nframes, uint32_t frame_size,
+ void (*notify)(struct tegra_ivc *))
+{
+ int ret;
+
+ if (!ivc)
+ return -EINVAL;
+
+ ret = check_ivc_params(rx_base, tx_base, nframes, frame_size);
+ if (ret)
+ return ret;
+
+ ivc->rx_channel = (struct tegra_ivc_channel_header *)rx_base;
+ ivc->tx_channel = (struct tegra_ivc_channel_header *)tx_base;
+ ivc->w_pos = 0;
+ ivc->r_pos = 0;
+ ivc->nframes = nframes;
+ ivc->frame_size = frame_size;
+ ivc->notify = notify;
+
+ return 0;
+}