[12/17] soc: qcom: ipa: immediate commands

diff --git a/drivers/net/ipa/ipa_cmd.c b/drivers/net/ipa/ipa_cmd.c
new file mode 100644
index 000000000000..e14a384f2886
--- /dev/null
+++ b/drivers/net/ipa/ipa_cmd.c
@@ -0,0 +1,680 @@ 
+// SPDX-License-Identifier: GPL-2.0
+
+/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
+ * Copyright (C) 2019-2020 Linaro Ltd.
+ */
+
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/bitfield.h>
+#include <linux/dma-direction.h>
+
+#include "gsi.h"
+#include "gsi_trans.h"
+#include "ipa.h"
+#include "ipa_endpoint.h"
+#include "ipa_table.h"
+#include "ipa_cmd.h"
+#include "ipa_mem.h"
+
+/**
+ * DOC:  IPA Immediate Commands
+ *
+ * The AP command TX endpoint is used to issue immediate commands to the IPA.
+ * An immediate command is generally used to request the IPA do something
+ * other than data transfer to another endpoint.
+ *
+ * Immediate commands are represented by GSI transactions just like other
+ * transfer requests, represented by a single GSI TRE.  Each immediate
+ * command has a well-defined format, having a payload of a known length.
+ * This allows the transfer element's length field to be used to hold an
+ * immediate command's opcode.  The payload for a command resides in DRAM
+ * and is described by a single scatterlist entry in its transaction.
+ * Commands do not require a transaction completion callback.  To commit
+ * an immediate command transaction, either gsi_trans_commit_wait() or
+ * gsi_trans_commit_wait_timeout() is used.
+ */
+
+/* Some commands can wait until indicated pipeline stages are clear */
+enum pipeline_clear_options {
+	pipeline_clear_hps	= 0,
+	pipeline_clear_src_grp	= 1,
+	pipeline_clear_full	= 2,
+};
+
+/* IPA_CMD_IP_V{4,6}_{FILTER,ROUTING}_INIT */
+
+struct ipa_cmd_hw_ip_fltrt_init {
+	__le64 hash_rules_addr;
+	__le64 flags;
+	__le64 nhash_rules_addr;
+};
+
+/* Field masks for ipa_cmd_hw_ip_fltrt_init structure fields */
+#define IP_FLTRT_FLAGS_HASH_SIZE_FMASK			GENMASK_ULL(11, 0)
+#define IP_FLTRT_FLAGS_HASH_ADDR_FMASK			GENMASK_ULL(27, 12)
+#define IP_FLTRT_FLAGS_NHASH_SIZE_FMASK			GENMASK_ULL(39, 28)
+#define IP_FLTRT_FLAGS_NHASH_ADDR_FMASK			GENMASK_ULL(55, 40)
+
+/* IPA_CMD_HDR_INIT_LOCAL */
+
+struct ipa_cmd_hw_hdr_init_local {
+	__le64 hdr_table_addr;
+	__le32 flags;
+	__le32 reserved;
+};
+
+/* Field masks for ipa_cmd_hw_hdr_init_local structure fields */
+#define HDR_INIT_LOCAL_FLAGS_TABLE_SIZE_FMASK		GENMASK(11, 0)
+#define HDR_INIT_LOCAL_FLAGS_HDR_ADDR_FMASK		GENMASK(27, 12)
+
+/* IPA_CMD_REGISTER_WRITE */
+
+/* For IPA v4.0+, this opcode gets modified with pipeline clear options */
+
+#define REGISTER_WRITE_OPCODE_SKIP_CLEAR_FMASK		GENMASK(8, 8)
+#define REGISTER_WRITE_OPCODE_CLEAR_OPTION_FMASK	GENMASK(10, 9)
+
+struct ipa_cmd_register_write {
+	__le16 flags;		/* Unused/reserved for IPA v3.5.1 */
+	__le16 offset;
+	__le32 value;
+	__le32 value_mask;
+	__le32 clear_options;	/* Unused/reserved for IPA v4.0+ */
+};
+
+/* Field masks for ipa_cmd_register_write structure fields */
+/* The next field is present for IPA v4.0 and above */
+#define REGISTER_WRITE_FLAGS_OFFSET_HIGH_FMASK		GENMASK(14, 11)
+/* The next field is present for IPA v3.5.1 only */
+#define REGISTER_WRITE_FLAGS_SKIP_CLEAR_FMASK		GENMASK(15, 15)
+
+/* The next field and its values are present for IPA v3.5.1 only */
+#define REGISTER_WRITE_CLEAR_OPTIONS_FMASK		GENMASK(1, 0)
+
+/* IPA_CMD_IP_PACKET_INIT */
+
+struct ipa_cmd_ip_packet_init {
+	u8 dest_endpoint;
+	u8 reserved[7];
+};
+
+/* Field masks for ipa_cmd_ip_packet_init dest_endpoint field */
+#define IPA_PACKET_INIT_DEST_ENDPOINT_FMASK		GENMASK(4, 0)
+
+/* IPA_CMD_DMA_TASK_32B_ADDR */
+
+/* This opcode gets modified with a DMA operation count */
+
+#define DMA_TASK_32B_ADDR_OPCODE_COUNT_FMASK		GENMASK(15, 8)
+
+struct ipa_cmd_hw_dma_task_32b_addr {
+	__le16 flags;
+	__le16 size;
+	__le32 addr;
+	__le16 packet_size;
+	u8 reserved[6];
+};
+
+/* Field masks for ipa_cmd_hw_dma_task_32b_addr flags field */
+#define DMA_TASK_32B_ADDR_FLAGS_SW_RSVD_FMASK		GENMASK(10, 0)
+#define DMA_TASK_32B_ADDR_FLAGS_CMPLT_FMASK		GENMASK(11, 11)
+#define DMA_TASK_32B_ADDR_FLAGS_EOF_FMASK		GENMASK(12, 12)
+#define DMA_TASK_32B_ADDR_FLAGS_FLSH_FMASK		GENMASK(13, 13)
+#define DMA_TASK_32B_ADDR_FLAGS_LOCK_FMASK		GENMASK(14, 14)
+#define DMA_TASK_32B_ADDR_FLAGS_UNLOCK_FMASK		GENMASK(15, 15)
+
+/* IPA_CMD_DMA_SHARED_MEM */
+
+/* For IPA v4.0+, this opcode gets modified with pipeline clear options */
+
+#define DMA_SHARED_MEM_OPCODE_SKIP_CLEAR_FMASK		GENMASK(8, 8)
+#define DMA_SHARED_MEM_OPCODE_CLEAR_OPTION_FMASK	GENMASK(10, 9)
+
+struct ipa_cmd_hw_dma_mem_mem {
+	__le16 clear_after_read; /* 0 or DMA_SHARED_MEM_CLEAR_AFTER_READ */
+	__le16 size;
+	__le16 local_addr;
+	__le16 flags;
+	__le64 system_addr;
+};
+
+/* Flag allowing atomic clear of target region after reading data (v4.0+)*/
+#define DMA_SHARED_MEM_CLEAR_AFTER_READ			GENMASK(15, 15)
+
+/* Field masks for ipa_cmd_hw_dma_mem_mem structure fields */
+#define DMA_SHARED_MEM_FLAGS_DIRECTION_FMASK		GENMASK(0, 0)
+/* The next two fields are present for IPA v3.5.1 only. */
+#define DMA_SHARED_MEM_FLAGS_SKIP_CLEAR_FMASK		GENMASK(1, 1)
+#define DMA_SHARED_MEM_FLAGS_CLEAR_OPTIONS_FMASK	GENMASK(3, 2)
+
+/* IPA_CMD_IP_PACKET_TAG_STATUS */
+
+struct ipa_cmd_ip_packet_tag_status {
+	__le64 tag;
+};
+
+#define IP_PACKET_TAG_STATUS_TAG_FMASK			GENMASK(63, 16)
+
+/* Immediate command payload */
+union ipa_cmd_payload {
+	struct ipa_cmd_hw_ip_fltrt_init table_init;
+	struct ipa_cmd_hw_hdr_init_local hdr_init_local;
+	struct ipa_cmd_register_write register_write;
+	struct ipa_cmd_ip_packet_init ip_packet_init;
+	struct ipa_cmd_hw_dma_task_32b_addr dma_task_32b_addr;
+	struct ipa_cmd_hw_dma_mem_mem dma_shared_mem;
+	struct ipa_cmd_ip_packet_tag_status ip_packet_tag_status;
+};
+
+static void ipa_cmd_validate_build(void)
+{
+	/* The sizes of a filter and route tables need to fit into fields
+	 * in the ipa_cmd_hw_ip_fltrt_init structure.  Although hashed tables
+	 * might not be used, non-hashed and hashed tables have the same
+	 * maximum size.  IPv4 and IPv6 filter tables have the same number
+	 * of entries, as and IPv4 and IPv6 route tables have the same number
+	 * of entries.
+	 */
+#define TABLE_SIZE	(TABLE_COUNT_MAX * IPA_TABLE_ENTRY_SIZE)
+#define TABLE_COUNT_MAX	max_t(u32, IPA_ROUTE_COUNT_MAX, IPA_FILTER_COUNT_MAX)
+	BUILD_BUG_ON(TABLE_SIZE > field_max(IP_FLTRT_FLAGS_HASH_SIZE_FMASK));
+	BUILD_BUG_ON(TABLE_SIZE > field_max(IP_FLTRT_FLAGS_NHASH_SIZE_FMASK));
+#undef TABLE_COUNT_MAX
+#undef TABLE_SIZE
+}
+
+#ifdef IPA_VALIDATE
+
+/* Validate a memory region holding a table */
+bool ipa_cmd_table_valid(struct ipa *ipa, const struct ipa_mem *mem,
+			 bool route, bool ipv6, bool hashed)
+{
+	struct device *dev = &ipa->pdev->dev;
+	u32 offset_max;
+
+	offset_max = hashed ? field_max(IP_FLTRT_FLAGS_HASH_ADDR_FMASK)
+			    : field_max(IP_FLTRT_FLAGS_NHASH_ADDR_FMASK);
+	if (mem->offset > offset_max ||
+	    ipa->mem_offset > offset_max - mem->offset) {
+		dev_err(dev, "IPv%c %s%s table region offset too large "
+			      "(0x%04x + 0x%04x > 0x%04x)\n",
+			      ipv6 ? '6' : '4', hashed ? "hashed " : "",
+			      route ? "route" : "filter",
+			      ipa->mem_offset, mem->offset, offset_max);
+		return false;
+	}
+
+	if (mem->offset > ipa->mem_size ||
+	    mem->size > ipa->mem_size - mem->offset) {
+		dev_err(dev, "IPv%c %s%s table region out of range "
+			      "(0x%04x + 0x%04x > 0x%04x)\n",
+			      ipv6 ? '6' : '4', hashed ? "hashed " : "",
+			      route ? "route" : "filter",
+			      mem->offset, mem->size, ipa->mem_size);
+		return false;
+	}
+
+	return true;
+}
+
+/* Validate the memory region that holds headers */
+static bool ipa_cmd_header_valid(struct ipa *ipa)
+{
+	const struct ipa_mem *mem = &ipa->mem[IPA_MEM_MODEM_HEADER];
+	struct device *dev = &ipa->pdev->dev;
+	u32 offset_max;
+	u32 size_max;
+	u32 size;
+
+	offset_max = field_max(HDR_INIT_LOCAL_FLAGS_HDR_ADDR_FMASK);
+	if (mem->offset > offset_max ||
+	    ipa->mem_offset > offset_max - mem->offset) {
+		dev_err(dev, "header table region offset too large "
+			      "(0x%04x + 0x%04x > 0x%04x)\n",
+			      ipa->mem_offset + mem->offset, offset_max);
+		return false;
+	}
+
+	size_max = field_max(HDR_INIT_LOCAL_FLAGS_TABLE_SIZE_FMASK);
+	size = ipa->mem[IPA_MEM_MODEM_HEADER].size;
+	size += ipa->mem[IPA_MEM_AP_HEADER].size;
+	if (mem->offset > ipa->mem_size || size > ipa->mem_size - mem->offset) {
+		dev_err(dev, "header table region out of range "
+			      "(0x%04x + 0x%04x > 0x%04x)\n",
+			      mem->offset, size, ipa->mem_size);
+		return false;
+	}
+
+	return true;
+}
+
+/* Indicate whether an offset can be used with a register_write command */
+static bool ipa_cmd_register_write_offset_valid(struct ipa *ipa,
+						const char *name, u32 offset)
+{
+	struct ipa_cmd_register_write *payload;
+	struct device *dev = &ipa->pdev->dev;
+	u32 offset_max;
+	u32 bit_count;
+
+	/* The maximum offset in a register_write immediate command depends
+	 * on the version of IPA.  IPA v3.5.1 supports a 16 bit offset, but
+	 * newer versions allow some additional high-order bits.
+	 */
+	bit_count = BITS_PER_BYTE * sizeof(payload->offset);
+	if (ipa->version != IPA_VERSION_3_5_1)
+		bit_count += hweight32(REGISTER_WRITE_FLAGS_OFFSET_HIGH_FMASK);
+	BUILD_BUG_ON(bit_count > 32);
+	offset_max = ~0 >> (32 - bit_count);
+
+	if (offset > offset_max || ipa->mem_offset > offset_max - offset) {
+		dev_err(dev, "%s offset too large 0x%04x + 0x%04x > 0x%04x)\n",
+				ipa->mem_offset + offset, offset_max);
+		return false;
+	}
+
+	return true;
+}
+
+/* Check whether offsets passed to register_write are valid */
+static bool ipa_cmd_register_write_valid(struct ipa *ipa)
+{
+	const char *name;
+	u32 offset;
+
+	offset = ipa_reg_filt_rout_hash_flush_offset(ipa->version);
+	name = "filter/route hash flush";
+	if (!ipa_cmd_register_write_offset_valid(ipa, name, offset))
+		return false;
+
+	offset = IPA_REG_ENDP_STATUS_N_OFFSET(IPA_ENDPOINT_COUNT);
+	name = "maximal endpoint status";
+	if (!ipa_cmd_register_write_offset_valid(ipa, name, offset))
+		return false;
+
+	return true;
+}
+
+bool ipa_cmd_data_valid(struct ipa *ipa)
+{
+	if (!ipa_cmd_header_valid(ipa))
+		return false;
+
+	if (!ipa_cmd_register_write_valid(ipa))
+		return false;
+
+	return true;
+}
+
+#endif /* IPA_VALIDATE */
+
+int ipa_cmd_pool_init(struct gsi_channel *channel, u32 tre_max)
+{
+	struct gsi_trans_info *trans_info = &channel->trans_info;
+	struct device *dev = channel->gsi->dev;
+	int ret;
+
+	/* This is as good a place as any to validate build constants */
+	ipa_cmd_validate_build();
+
+	/* Even though command payloads are allocated one at a time,
+	 * a single transaction can require up to tlv_count of them,
+	 * so we treat them as if that many can be allocated at once.
+	 */
+	ret = gsi_trans_pool_init_dma(dev, &trans_info->cmd_pool,
+				      sizeof(union ipa_cmd_payload),
+				      tre_max, channel->tlv_count);
+	if (ret)
+		return ret;
+
+	/* Each TRE needs a command info structure */
+	ret = gsi_trans_pool_init(&trans_info->info_pool,
+				   sizeof(struct ipa_cmd_info),
+				   tre_max, channel->tlv_count);
+	if (ret)
+		gsi_trans_pool_exit_dma(dev, &trans_info->cmd_pool);
+
+	return ret;
+}
+
+void ipa_cmd_pool_exit(struct gsi_channel *channel)
+{
+	struct gsi_trans_info *trans_info = &channel->trans_info;
+	struct device *dev = channel->gsi->dev;
+
+	gsi_trans_pool_exit(&trans_info->info_pool);
+	gsi_trans_pool_exit_dma(dev, &trans_info->cmd_pool);
+}
+
+static union ipa_cmd_payload *
+ipa_cmd_payload_alloc(struct ipa *ipa, dma_addr_t *addr)
+{
+	struct gsi_trans_info *trans_info;
+	struct ipa_endpoint *endpoint;
+
+	endpoint = ipa->name_map[IPA_ENDPOINT_AP_COMMAND_TX];
+	trans_info = &ipa->gsi.channel[endpoint->channel_id].trans_info;
+
+	return gsi_trans_pool_alloc_dma(&trans_info->cmd_pool, addr);
+}
+
+/* If hash_size is 0, hash_offset and hash_addr ignored. */
+void ipa_cmd_table_init_add(struct gsi_trans *trans,
+			    enum ipa_cmd_opcode opcode, u16 size, u32 offset,
+			    dma_addr_t addr, u16 hash_size, u32 hash_offset,
+			    dma_addr_t hash_addr)
+{
+	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
+	enum dma_data_direction direction = DMA_TO_DEVICE;
+	struct ipa_cmd_hw_ip_fltrt_init *payload;
+	union ipa_cmd_payload *cmd_payload;
+	dma_addr_t payload_addr;
+	u64 val;
+
+	/* Record the non-hash table offset and size */
+	offset += ipa->mem_offset;
+	val = u64_encode_bits(offset, IP_FLTRT_FLAGS_NHASH_ADDR_FMASK);
+	val |= u64_encode_bits(size, IP_FLTRT_FLAGS_NHASH_SIZE_FMASK);
+
+	/* The hash table offset and address are zero if its size is 0 */
+	if (hash_size) {
+		/* Record the hash table offset and size */
+		hash_offset += ipa->mem_offset;
+		val |= u64_encode_bits(hash_offset,
+				       IP_FLTRT_FLAGS_HASH_ADDR_FMASK);
+		val |= u64_encode_bits(hash_size,
+				       IP_FLTRT_FLAGS_HASH_SIZE_FMASK);
+	}
+
+	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
+	payload = &cmd_payload->table_init;
+
+	/* Fill in all offsets and sizes and the non-hash table address */
+	if (hash_size)
+		payload->hash_rules_addr = cpu_to_le64(hash_addr);
+	payload->flags = cpu_to_le64(val);
+	payload->nhash_rules_addr = cpu_to_le64(addr);
+
+	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
+			  direction, opcode);
+}
+
+/* Initialize header space in IPA-local memory */
+void ipa_cmd_hdr_init_local_add(struct gsi_trans *trans, u32 offset, u16 size,
+				dma_addr_t addr)
+{
+	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
+	enum ipa_cmd_opcode opcode = IPA_CMD_HDR_INIT_LOCAL;
+	enum dma_data_direction direction = DMA_TO_DEVICE;
+	struct ipa_cmd_hw_hdr_init_local *payload;
+	union ipa_cmd_payload *cmd_payload;
+	dma_addr_t payload_addr;
+	u32 flags;
+
+	offset += ipa->mem_offset;
+
+	/* With this command we tell the IPA where in its local memory the
+	 * header tables reside.  The content of the buffer provided is
+	 * also written via DMA into that space.  The IPA hardware owns
+	 * the table, but the AP must initialize it.
+	 */
+	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
+	payload = &cmd_payload->hdr_init_local;
+
+	payload->hdr_table_addr = cpu_to_le64(addr);
+	flags = u32_encode_bits(size, HDR_INIT_LOCAL_FLAGS_TABLE_SIZE_FMASK);
+	flags |= u32_encode_bits(offset, HDR_INIT_LOCAL_FLAGS_HDR_ADDR_FMASK);
+	payload->flags = cpu_to_le32(flags);
+
+	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
+			  direction, opcode);
+}
+
+void ipa_cmd_register_write_add(struct gsi_trans *trans, u32 offset, u32 value,
+				u32 mask, bool clear_full)
+{
+	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
+	struct ipa_cmd_register_write *payload;
+	union ipa_cmd_payload *cmd_payload;
+	u32 opcode = IPA_CMD_REGISTER_WRITE;
+	dma_addr_t payload_addr;
+	u32 clear_option;
+	u32 options;
+	u16 flags;
+
+	/* pipeline_clear_src_grp is not used */
+	clear_option = clear_full ? pipeline_clear_full : pipeline_clear_hps;
+
+	if (ipa->version != IPA_VERSION_3_5_1) {
+		u16 offset_high;
+		u32 val;
+
+		/* Opcode encodes pipeline clear options */
+		/* SKIP_CLEAR is always 0 (don't skip pipeline clear) */
+		val = u16_encode_bits(clear_option,
+				      REGISTER_WRITE_OPCODE_CLEAR_OPTION_FMASK);
+		opcode |= val;
+
+		/* Extract the high 4 bits from the offset */
+		offset_high = (u16)u32_get_bits(offset, GENMASK(19, 16));
+		offset &= (1 << 16) - 1;
+
+		/* Extract the top 4 bits and encode it into the flags field */
+		flags = u16_encode_bits(offset_high,
+				REGISTER_WRITE_FLAGS_OFFSET_HIGH_FMASK);
+		options = 0;	/* reserved */
+
+	} else {
+		flags = 0;	/* SKIP_CLEAR flag is always 0 */
+		options = u16_encode_bits(clear_option,
+					  REGISTER_WRITE_CLEAR_OPTIONS_FMASK);
+	}
+
+	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
+	payload = &cmd_payload->register_write;
+
+	payload->flags = cpu_to_le16(flags);
+	payload->offset = cpu_to_le16((u16)offset);
+	payload->value = cpu_to_le32(value);
+	payload->value_mask = cpu_to_le32(mask);
+	payload->clear_options = cpu_to_le32(options);
+
+	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
+			  DMA_NONE, opcode);
+}
+
+/* Skip IP packet processing on the next data transfer on a TX channel */
+static void ipa_cmd_ip_packet_init_add(struct gsi_trans *trans, u8 endpoint_id)
+{
+	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
+	enum ipa_cmd_opcode opcode = IPA_CMD_IP_PACKET_INIT;
+	enum dma_data_direction direction = DMA_TO_DEVICE;
+	struct ipa_cmd_ip_packet_init *payload;
+	union ipa_cmd_payload *cmd_payload;
+	dma_addr_t payload_addr;
+
+	/* assert(endpoint_id <
+		  field_max(IPA_PACKET_INIT_DEST_ENDPOINT_FMASK)); */
+
+	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
+	payload = &cmd_payload->ip_packet_init;
+
+	payload->dest_endpoint = u8_encode_bits(endpoint_id,
+					IPA_PACKET_INIT_DEST_ENDPOINT_FMASK);
+
+	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
+			  direction, opcode);
+}
+
+/* Use a 32-bit DMA command to zero a block of memory */
+void ipa_cmd_dma_task_32b_addr_add(struct gsi_trans *trans, u16 size,
+				   dma_addr_t addr, bool toward_ipa)
+{
+	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
+	enum ipa_cmd_opcode opcode = IPA_CMD_DMA_TASK_32B_ADDR;
+	struct ipa_cmd_hw_dma_task_32b_addr *payload;
+	union ipa_cmd_payload *cmd_payload;
+	enum dma_data_direction direction;
+	dma_addr_t payload_addr;
+	u16 flags;
+
+	/* assert(addr <= U32_MAX); */
+	addr &= GENMASK_ULL(31, 0);
+
+	/* The opcode encodes the number of DMA operations in the high byte */
+	opcode |= u16_encode_bits(1, DMA_TASK_32B_ADDR_OPCODE_COUNT_FMASK);
+
+	direction = toward_ipa ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
+
+	/* complete: 0 = don't interrupt; eof: 0 = don't assert eot */
+	flags = DMA_TASK_32B_ADDR_FLAGS_FLSH_FMASK;
+	/* lock: 0 = don't lock endpoint; unlock: 0 = don't unlock */
+
+	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
+	payload = &cmd_payload->dma_task_32b_addr;
+
+	payload->flags = cpu_to_le16(flags);
+	payload->size = cpu_to_le16(size);
+	payload->addr = cpu_to_le32((u32)addr);
+	payload->packet_size = cpu_to_le16(size);
+
+	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
+			  direction, opcode);
+}
+
+/* Use a DMA command to read or write a block of IPA-resident memory */
+void ipa_cmd_dma_shared_mem_add(struct gsi_trans *trans, u32 offset, u16 size,
+				dma_addr_t addr, bool toward_ipa)
+{
+	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
+	enum ipa_cmd_opcode opcode = IPA_CMD_DMA_SHARED_MEM;
+	struct ipa_cmd_hw_dma_mem_mem *payload;
+	union ipa_cmd_payload *cmd_payload;
+	enum dma_data_direction direction;
+	dma_addr_t payload_addr;
+	u16 flags;
+
+	/* size and offset must fit in 16 bit fields */
+	/* assert(size > 0 && size <= U16_MAX); */
+	/* assert(offset <= U16_MAX && ipa->mem_offset <= U16_MAX - offset); */
+
+	offset += ipa->mem_offset;
+
+	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
+	payload = &cmd_payload->dma_shared_mem;
+
+	/* payload->clear_after_read was reserved prior to IPA v4.0.  It's
+	 * never needed for current code, so it's 0 regardless of version.
+	 */
+	payload->size = cpu_to_le16(size);
+	payload->local_addr = cpu_to_le16(offset);
+	/* payload->flags:
+	 *   direction:		0 = write to IPA, 1 read from IPA
+	 * Starting at v4.0 these are reserved; either way, all zero:
+	 *   pipeline clear:	0 = wait for pipeline clear (don't skip)
+	 *   clear_options:	0 = pipeline_clear_hps
+	 * Instead, for v4.0+ these are encoded in the opcode.  But again
+	 * since both values are 0 we won't bother OR'ing them in.
+	 */
+	flags = toward_ipa ? 0 : DMA_SHARED_MEM_FLAGS_DIRECTION_FMASK;
+	payload->flags = cpu_to_le16(flags);
+	payload->system_addr = cpu_to_le64(addr);
+
+	direction = toward_ipa ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
+
+	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
+			  direction, opcode);
+}
+
+static void ipa_cmd_ip_tag_status_add(struct gsi_trans *trans, u64 tag)
+{
+	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
+	enum ipa_cmd_opcode opcode = IPA_CMD_IP_PACKET_TAG_STATUS;
+	enum dma_data_direction direction = DMA_TO_DEVICE;
+	struct ipa_cmd_ip_packet_tag_status *payload;
+	union ipa_cmd_payload *cmd_payload;
+	dma_addr_t payload_addr;
+
+	/* assert(tag <= field_max(IP_PACKET_TAG_STATUS_TAG_FMASK)); */
+
+	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
+	payload = &cmd_payload->ip_packet_tag_status;
+
+	payload->tag = u64_encode_bits(tag, IP_PACKET_TAG_STATUS_TAG_FMASK);
+
+	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
+			  direction, opcode);
+}
+
+/* Issue a small command TX data transfer */
+static void ipa_cmd_transfer_add(struct gsi_trans *trans, u16 size)
+{
+	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
+	enum dma_data_direction direction = DMA_TO_DEVICE;
+	enum ipa_cmd_opcode opcode = IPA_CMD_NONE;
+	union ipa_cmd_payload *payload;
+	dma_addr_t payload_addr;
+
+	/* assert(size <= sizeof(*payload)); */
+
+	/* Just transfer a zero-filled payload structure */
+	payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
+
+	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
+			  direction, opcode);
+}
+
+void ipa_cmd_tag_process_add(struct gsi_trans *trans)
+{
+	ipa_cmd_register_write_add(trans, 0, 0, 0, true);
+#if 1
+	/* Reference these functions to avoid a compile error */
+	(void)ipa_cmd_ip_packet_init_add;
+	(void)ipa_cmd_ip_tag_status_add;
+	(void) ipa_cmd_transfer_add;
+#else
+	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
+	struct gsi_endpoint *endpoint;
+
+	endpoint = ipa->name_map[IPA_ENDPOINT_AP_LAN_RX];
+	ipa_cmd_ip_packet_init_add(trans, endpoint->endpoint_id);
+
+	ipa_cmd_ip_tag_status_add(trans, 0xcba987654321);
+
+	ipa_cmd_transfer_add(trans, 4);
+#endif
+}
+
+/* Returns the number of commands required for the tag process */
+u32 ipa_cmd_tag_process_count(void)
+{
+	return 4;
+}
+
+static struct ipa_cmd_info *
+ipa_cmd_info_alloc(struct ipa_endpoint *endpoint, u32 tre_count)
+{
+	struct gsi_channel *channel;
+
+	channel = &endpoint->ipa->gsi.channel[endpoint->channel_id];
+
+	return gsi_trans_pool_alloc(&channel->trans_info.info_pool, tre_count);
+}
+
+/* Allocate a transaction for the command TX endpoint */
+struct gsi_trans *ipa_cmd_trans_alloc(struct ipa *ipa, u32 tre_count)
+{
+	struct ipa_endpoint *endpoint;
+	struct gsi_trans *trans;
+
+	endpoint = ipa->name_map[IPA_ENDPOINT_AP_COMMAND_TX];
+
+	trans = gsi_channel_trans_alloc(&ipa->gsi, endpoint->channel_id,
+					tre_count, DMA_NONE);
+	if (trans)
+		trans->info = ipa_cmd_info_alloc(endpoint, tre_count);
+
+	return trans;
+}
diff --git a/drivers/net/ipa/ipa_cmd.h b/drivers/net/ipa/ipa_cmd.h
new file mode 100644
index 000000000000..4917525b3a47
--- /dev/null
+++ b/drivers/net/ipa/ipa_cmd.h
@@ -0,0 +1,195 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
+ * Copyright (C) 2019-2020 Linaro Ltd.
+ */
+#ifndef _IPA_CMD_H_
+#define _IPA_CMD_H_
+
+#include <linux/types.h>
+#include <linux/dma-direction.h>
+
+struct sk_buff;
+struct scatterlist;
+
+struct ipa;
+struct ipa_mem;
+struct gsi_trans;
+struct gsi_channel;
+
+/**
+ * enum ipa_cmd_opcode:	IPA immediate commands
+ *
+ * All immediate commands are issued using the AP command TX endpoint.
+ * The numeric values here are the opcodes for IPA v3.5.1 hardware.
+ *
+ * IPA_CMD_NONE is a special (invalid) value that's used to indicate
+ * a request is *not* an immediate command.
+ */
+enum ipa_cmd_opcode {
+	IPA_CMD_NONE			= 0,
+	IPA_CMD_IP_V4_FILTER_INIT	= 3,
+	IPA_CMD_IP_V6_FILTER_INIT	= 4,
+	IPA_CMD_IP_V4_ROUTING_INIT	= 7,
+	IPA_CMD_IP_V6_ROUTING_INIT	= 8,
+	IPA_CMD_HDR_INIT_LOCAL		= 9,
+	IPA_CMD_REGISTER_WRITE		= 12,
+	IPA_CMD_IP_PACKET_INIT		= 16,
+	IPA_CMD_DMA_TASK_32B_ADDR	= 17,
+	IPA_CMD_DMA_SHARED_MEM		= 19,
+	IPA_CMD_IP_PACKET_TAG_STATUS	= 20,
+};
+
+/**
+ * struct ipa_cmd_info - information needed for an IPA immediate command
+ *
+ * @opcode:	The command opcode.
+ * @direction:	Direction of data transfer for DMA commands
+ */
+struct ipa_cmd_info {
+	enum ipa_cmd_opcode opcode;
+	enum dma_data_direction direction;
+};
+
+
+#ifdef IPA_VALIDATE
+
+/**
+ * ipa_cmd_table_valid() - Validate a memory region holding a table
+ * @ipa:	- IPA pointer
+ * @mem:	- IPA memory region descriptor
+ * @route:	- Whether the region holds a route or filter table
+ * @ipv6:	- Whether the table is for IPv6 or IPv4
+ * @hashed:	- Whether the table is hashed or non-hashed
+ *
+ * @Return:	true if region is valid, false otherwise
+ */
+bool ipa_cmd_table_valid(struct ipa *ipa, const struct ipa_mem *mem,
+			    bool route, bool ipv6, bool hashed);
+
+/**
+ * ipa_cmd_data_valid() - Validate command-realted configuration is valid
+ * @ipa:	- IPA pointer
+ *
+ * @Return:	true if assumptions required for command are valid
+ */
+bool ipa_cmd_data_valid(struct ipa *ipa);
+
+#else /* !IPA_VALIDATE */
+
+static inline bool ipa_cmd_table_valid(struct ipa *ipa,
+				       const struct ipa_mem *mem, bool route,
+				       bool ipv6, bool hashed)
+{
+	return true;
+}
+
+static inline bool ipa_cmd_data_valid(struct ipa *ipa)
+{
+	return true;
+}
+
+#endif /* !IPA_VALIDATE */
+
+/**
+ * ipa_cmd_pool_init() - initialize command channel pools
+ * @channel:	AP->IPA command TX GSI channel pointer
+ * @tre_count:	Number of pool elements to allocate
+ *
+ * @Return:	0 if successful, or a negative error code
+ */
+int ipa_cmd_pool_init(struct gsi_channel *gsi_channel, u32 tre_count);
+
+/**
+ * ipa_cmd_pool_exit() - Inverse of ipa_cmd_pool_init()
+ * @channel:	AP->IPA command TX GSI channel pointer
+ */
+void ipa_cmd_pool_exit(struct gsi_channel *channel);
+
+/**
+ * ipa_cmd_table_init_add() - Add table init command to a transaction
+ * @trans:	GSI transaction
+ * @opcode:	IPA immediate command opcode
+ * @size:	Size of non-hashed routing table memory
+ * @offset:	Offset in IPA shared memory of non-hashed routing table memory
+ * @addr:	DMA address of non-hashed table data to write
+ * @hash_size:	Size of hashed routing table memory
+ * @hash_offset: Offset in IPA shared memory of hashed routing table memory
+ * @hash_addr:	DMA address of hashed table data to write
+ *
+ * If hash_size is 0, hash_offset and hash_addr are ignored.
+ */
+void ipa_cmd_table_init_add(struct gsi_trans *trans, enum ipa_cmd_opcode opcode,
+			    u16 size, u32 offset, dma_addr_t addr,
+			    u16 hash_size, u32 hash_offset,
+			    dma_addr_t hash_addr);
+
+/**
+ * ipa_cmd_hdr_init_local_add() - Add a header init command to a transaction
+ * @ipa:	IPA structure
+ * @offset:	Offset of header memory in IPA local space
+ * @size:	Size of header memory
+ * @addr:	DMA address of buffer to be written from
+ *
+ * Defines and fills the location in IPA memory to use for headers.
+ */
+void ipa_cmd_hdr_init_local_add(struct gsi_trans *trans, u32 offset, u16 size,
+				dma_addr_t addr);
+
+/**
+ * ipa_cmd_register_write_add() - Add a register write command to a transaction
+ * @trans:	GSI transaction
+ * @offset:	Offset of register to be written
+ * @value:	Value to be written
+ * @mask:	Mask of bits in register to update with bits from value
+ * @clear_full: Pipeline clear option; true means full pipeline clear
+ */
+void ipa_cmd_register_write_add(struct gsi_trans *trans, u32 offset, u32 value,
+				u32 mask, bool clear_full);
+
+/**
+ * ipa_cmd_dma_task_32b_addr_add() - Add a 32-bit DMA command to a transaction
+ * @trans:	GSi transaction
+ * @size:	Number of bytes to be memory to be transferred
+ * @addr:	DMA address of buffer to be read into or written from
+ * @toward_ipa:	true means write to IPA memory; false means read
+ */
+void ipa_cmd_dma_task_32b_addr_add(struct gsi_trans *trans, u16 size,
+				   dma_addr_t addr, bool toward_ipa);
+
+/**
+ * ipa_cmd_dma_shared_mem_add() - Add a DMA memory command to a transaction
+ * @trans:	GSI transaction
+ * @offset:	Offset of IPA memory to be read or written
+ * @size:	Number of bytes of memory to be transferred
+ * @addr:	DMA address of buffer to be read into or written from
+ * @toward_ipa:	true means write to IPA memory; false means read
+ */
+void ipa_cmd_dma_shared_mem_add(struct gsi_trans *trans, u32 offset,
+				u16 size, dma_addr_t addr, bool toward_ipa);
+
+/**
+ * ipa_cmd_tag_process_add() - Add IPA tag process commands to a transaction
+ * @trans:	GSI transaction
+ */
+void ipa_cmd_tag_process_add(struct gsi_trans *trans);
+
+/**
+ * ipa_cmd_tag_process_add_count() - Number of commands in a tag process
+ *
+ * @Return:	The number of elements to allocate in a transaction
+ *		to hold tag process commands
+ */
+u32 ipa_cmd_tag_process_count(void);
+
+/**
+ * ipa_cmd_trans_alloc() - Allocate a transaction for the command TX endpoint
+ * @ipa:	IPA pointer
+ * @tre_count:	Number of elements in the transaction
+ *
+ * @Return:	A GSI transaction structure, or a null pointer if all
+ *		available transactions are in use
+ */
+struct gsi_trans *ipa_cmd_trans_alloc(struct ipa *ipa, u32 tre_count);
+
+#endif /* _IPA_CMD_H_ */