soc: qcom: ipa: GSI headers

The Generic Software Interface is a layer of the IPA driver that
abstracts the underlying hardware.  The next patch includes the
main code for GSI (including some additional documentation).  This
patch just includes three GSI header files.

  - "gsi.h" is the top-level GSI header file.  This structure is
    is embedded within the IPA structure.  The main abstraction
    implemented by the GSI code is the channel, and this header
    exposes several operations that can be performed on a GSI channel.

  - "gsi_private.h" exposes some definitions that are intended to be
    private, used only by the main GSI code and the GSI transaction
    code (defined in an upcoming patch).

  - Like "ipa_reg.h", "gsi_reg.h" defines the offsets of the 32-bit
    registers used by the GSI layer, along with masks that define the
    position and width of fields less than 32 bits located within
    these registers.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 118 insertions, 0 deletions

diff --git a/drivers/net/ipa/gsi_private.h b/drivers/net/ipa/gsi_private.h
new file mode 100644
index 000000000000..b57d0198ebc1
--- /dev/null
+++ b/drivers/net/ipa/gsi_private.h
@@ -0,0 +1,118 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/* Copyright (c) 2015-2018, The Linux Foundation. All rights reserved.
+ * Copyright (C) 2018-2020 Linaro Ltd.
+ */
+#ifndef _GSI_PRIVATE_H_
+#define _GSI_PRIVATE_H_
+
+/* === Only "gsi.c" and "gsi_trans.c" should include this file === */
+
+#include <linux/types.h>
+
+struct gsi_trans;
+struct gsi_ring;
+struct gsi_channel;
+
+#define GSI_RING_ELEMENT_SIZE	16	/* bytes */
+
+/* Return the entry that follows one provided in a transaction pool */
+void *gsi_trans_pool_next(struct gsi_trans_pool *pool, void *element);
+
+/**
+ * gsi_trans_move_complete() - Mark a GSI transaction completed
+ * @trans:	Transaction to commit
+ */
+void gsi_trans_move_complete(struct gsi_trans *trans);
+
+/**
+ * gsi_trans_move_polled() - Mark a transaction polled
+ * @trans:	Transaction to update
+ */
+void gsi_trans_move_polled(struct gsi_trans *trans);
+
+/**
+ * gsi_trans_complete() - Complete a GSI transaction
+ * @trans:	Transaction to complete
+ *
+ * Marks a transaction complete (including freeing it).
+ */
+void gsi_trans_complete(struct gsi_trans *trans);
+
+/**
+ * gsi_channel_trans_mapped() - Return a transaction mapped to a TRE index
+ * @channel:	Channel associated with the transaction
+ * @index:	Index of the TRE having a transaction
+ *
+ * @Return:	The GSI transaction pointer associated with the TRE index
+ */
+struct gsi_trans *gsi_channel_trans_mapped(struct gsi_channel *channel,
+					   u32 index);
+
+/**
+ * gsi_channel_trans_complete() - Return a channel's next completed transaction
+ * @channel:	Channel whose next transaction is to be returned
+ *
+ * @Return:	The next completed transaction, or NULL if nothing new
+ */
+struct gsi_trans *gsi_channel_trans_complete(struct gsi_channel *channel);
+
+/**
+ * gsi_channel_trans_cancel_pending() - Cancel pending transactions
+ * @channel:	Channel whose pending transactions should be cancelled
+ *
+ * Cancel all pending transactions on a channel.  These are transactions
+ * that have been committed but not yet completed.  This is required when
+ * the channel gets reset.  At that time all pending transactions will be
+ * marked as cancelled.
+ *
+ * NOTE:  Transactions already complete at the time of this call are
+ *	  unaffected.
+ */
+void gsi_channel_trans_cancel_pending(struct gsi_channel *channel);
+
+/**
+ * gsi_channel_trans_init() - Initialize a channel's GSI transaction info
+ * @gsi:	GSI pointer
+ * @channel_id:	Channel number
+ *
+ * @Return:	0 if successful, or -ENOMEM on allocation failure
+ *
+ * Creates and sets up information for managing transactions on a channel
+ */
+int gsi_channel_trans_init(struct gsi *gsi, u32 channel_id);
+
+/**
+ * gsi_channel_trans_exit() - Inverse of gsi_channel_trans_init()
+ * @channel:	Channel whose transaction information is to be cleaned up
+ */
+void gsi_channel_trans_exit(struct gsi_channel *channel);
+
+/**
+ * gsi_channel_doorbell() - Ring a channel's doorbell
+ * @channel:	Channel whose doorbell should be rung
+ *
+ * Rings a channel's doorbell to inform the GSI hardware that new
+ * transactions (TREs, really) are available for it to process.
+ */
+void gsi_channel_doorbell(struct gsi_channel *channel);
+
+/**
+ * gsi_ring_virt() - Return virtual address for a ring entry
+ * @ring:	Ring whose address is to be translated
+ * @addr:	Index (slot number) of entry
+ */
+void *gsi_ring_virt(struct gsi_ring *ring, u32 index);
+
+/**
+ * gsi_channel_tx_queued() - Report the number of bytes queued to hardware
+ * @channel:	Channel whose bytes have been queued
+ *
+ * This arranges for the the number of transactions and bytes for
+ * transfer that have been queued to hardware to be reported.  It
+ * passes this information up the network stack so it can be used to
+ * throttle transmissions.
+ */
+void gsi_channel_tx_queued(struct gsi_channel *channel);
+
+#endif /* _GSI_PRIVATE_H_ */