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path: root/drivers/net/ipa/ipa_table.c
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Diffstat (limited to 'drivers/net/ipa/ipa_table.c')
-rw-r--r--drivers/net/ipa/ipa_table.c708
1 files changed, 708 insertions, 0 deletions
diff --git a/drivers/net/ipa/ipa_table.c b/drivers/net/ipa/ipa_table.c
new file mode 100644
index 000000000..cd81dd916
--- /dev/null
+++ b/drivers/net/ipa/ipa_table.c
@@ -0,0 +1,708 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
+ * Copyright (C) 2018-2022 Linaro Ltd.
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/bits.h>
+#include <linux/bitops.h>
+#include <linux/bitfield.h>
+#include <linux/io.h>
+#include <linux/build_bug.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+
+#include "ipa.h"
+#include "ipa_version.h"
+#include "ipa_endpoint.h"
+#include "ipa_table.h"
+#include "ipa_reg.h"
+#include "ipa_mem.h"
+#include "ipa_cmd.h"
+#include "gsi.h"
+#include "gsi_trans.h"
+
+/**
+ * DOC: IPA Filter and Route Tables
+ *
+ * The IPA has tables defined in its local (IPA-resident) memory that define
+ * filter and routing rules. An entry in either of these tables is a little
+ * endian 64-bit "slot" that holds the address of a rule definition. (The
+ * size of these slots is 64 bits regardless of the host DMA address size.)
+ *
+ * Separate tables (both filter and route) used for IPv4 and IPv6. There
+ * are normally another set of "hashed" filter and route tables, which are
+ * used with a hash of message metadata. Hashed operation is not supported
+ * by all IPA hardware (IPA v4.2 doesn't support hashed tables).
+ *
+ * Rules can be in local memory or in DRAM (system memory). The offset of
+ * an object (such as a route or filter table) in IPA-resident memory must
+ * 128-byte aligned. An object in system memory (such as a route or filter
+ * rule) must be at an 8-byte aligned address. We currently only place
+ * route or filter rules in system memory.
+ *
+ * A rule consists of a contiguous block of 32-bit values terminated with
+ * 32 zero bits. A special "zero entry" rule consisting of 64 zero bits
+ * represents "no filtering" or "no routing," and is the reset value for
+ * filter or route table rules.
+ *
+ * Each filter rule is associated with an AP or modem TX endpoint, though
+ * not all TX endpoints support filtering. The first 64-bit slot in a
+ * filter table is a bitmap indicating which endpoints have entries in
+ * the table. The low-order bit (bit 0) in this bitmap represents a
+ * special global filter, which applies to all traffic. This is not
+ * used in the current code. Bit 1, if set, indicates that there is an
+ * entry (i.e. slot containing a system address referring to a rule) for
+ * endpoint 0 in the table. Bit 3, if set, indicates there is an entry
+ * for endpoint 2, and so on. Space is set aside in IPA local memory to
+ * hold as many filter table entries as might be required, but typically
+ * they are not all used.
+ *
+ * The AP initializes all entries in a filter table to refer to a "zero"
+ * entry. Once initialized the modem and AP update the entries for
+ * endpoints they "own" directly. Currently the AP does not use the
+ * IPA filtering functionality.
+ *
+ * IPA Filter Table
+ * ----------------------
+ * endpoint bitmap | 0x0000000000000048 | Bits 3 and 6 set (endpoints 2 and 5)
+ * |--------------------|
+ * 1st endpoint | 0x000123456789abc0 | DMA address for modem endpoint 2 rule
+ * |--------------------|
+ * 2nd endpoint | 0x000123456789abf0 | DMA address for AP endpoint 5 rule
+ * |--------------------|
+ * (unused) | | (Unused space in filter table)
+ * |--------------------|
+ * . . .
+ * |--------------------|
+ * (unused) | | (Unused space in filter table)
+ * ----------------------
+ *
+ * The set of available route rules is divided about equally between the AP
+ * and modem. The AP initializes all entries in a route table to refer to
+ * a "zero entry". Once initialized, the modem and AP are responsible for
+ * updating their own entries. All entries in a route table are usable,
+ * though the AP currently does not use the IPA routing functionality.
+ *
+ * IPA Route Table
+ * ----------------------
+ * 1st modem route | 0x0001234500001100 | DMA address for first route rule
+ * |--------------------|
+ * 2nd modem route | 0x0001234500001140 | DMA address for second route rule
+ * |--------------------|
+ * . . .
+ * |--------------------|
+ * Last modem route| 0x0001234500002280 | DMA address for Nth route rule
+ * |--------------------|
+ * 1st AP route | 0x0001234500001100 | DMA address for route rule (N+1)
+ * |--------------------|
+ * 2nd AP route | 0x0001234500001140 | DMA address for next route rule
+ * |--------------------|
+ * . . .
+ * |--------------------|
+ * Last AP route | 0x0001234500002280 | DMA address for last route rule
+ * ----------------------
+ */
+
+/* Assignment of route table entries to the modem and AP */
+#define IPA_ROUTE_MODEM_MIN 0
+#define IPA_ROUTE_AP_MIN IPA_ROUTE_MODEM_COUNT
+#define IPA_ROUTE_AP_COUNT \
+ (IPA_ROUTE_COUNT_MAX - IPA_ROUTE_MODEM_COUNT)
+
+/* Filter or route rules consist of a set of 32-bit values followed by a
+ * 32-bit all-zero rule list terminator. The "zero rule" is simply an
+ * all-zero rule followed by the list terminator.
+ */
+#define IPA_ZERO_RULE_SIZE (2 * sizeof(__le32))
+
+/* Check things that can be validated at build time. */
+static void ipa_table_validate_build(void)
+{
+ /* Filter and route tables contain DMA addresses that refer
+ * to filter or route rules. But the size of a table entry
+ * is 64 bits regardless of what the size of an AP DMA address
+ * is. A fixed constant defines the size of an entry, and
+ * code in ipa_table_init() uses a pointer to __le64 to
+ * initialize tables.
+ */
+ BUILD_BUG_ON(sizeof(dma_addr_t) > sizeof(__le64));
+
+ /* A "zero rule" is used to represent no filtering or no routing.
+ * It is a 64-bit block of zeroed memory. Code in ipa_table_init()
+ * assumes that it can be written using a pointer to __le64.
+ */
+ BUILD_BUG_ON(IPA_ZERO_RULE_SIZE != sizeof(__le64));
+
+ /* Impose a practical limit on the number of routes */
+ BUILD_BUG_ON(IPA_ROUTE_COUNT_MAX > 32);
+ /* The modem must be allotted at least one route table entry */
+ BUILD_BUG_ON(!IPA_ROUTE_MODEM_COUNT);
+ /* But it can't have more than what is available */
+ BUILD_BUG_ON(IPA_ROUTE_MODEM_COUNT > IPA_ROUTE_COUNT_MAX);
+
+}
+
+static bool
+ipa_table_valid_one(struct ipa *ipa, enum ipa_mem_id mem_id, bool route)
+{
+ const struct ipa_mem *mem = ipa_mem_find(ipa, mem_id);
+ struct device *dev = &ipa->pdev->dev;
+ u32 size;
+
+ if (route)
+ size = IPA_ROUTE_COUNT_MAX * sizeof(__le64);
+ else
+ size = (1 + IPA_FILTER_COUNT_MAX) * sizeof(__le64);
+
+ if (!ipa_cmd_table_valid(ipa, mem, route))
+ return false;
+
+ /* mem->size >= size is sufficient, but we'll demand more */
+ if (mem->size == size)
+ return true;
+
+ /* Hashed table regions can be zero size if hashing is not supported */
+ if (ipa_table_hash_support(ipa) && !mem->size)
+ return true;
+
+ dev_err(dev, "%s table region %u size 0x%02x, expected 0x%02x\n",
+ route ? "route" : "filter", mem_id, mem->size, size);
+
+ return false;
+}
+
+/* Verify the filter and route table memory regions are the expected size */
+bool ipa_table_valid(struct ipa *ipa)
+{
+ bool valid;
+
+ valid = ipa_table_valid_one(ipa, IPA_MEM_V4_FILTER, false);
+ valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V6_FILTER, false);
+ valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V4_ROUTE, true);
+ valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V6_ROUTE, true);
+
+ if (!ipa_table_hash_support(ipa))
+ return valid;
+
+ valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V4_FILTER_HASHED,
+ false);
+ valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V6_FILTER_HASHED,
+ false);
+ valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V4_ROUTE_HASHED,
+ true);
+ valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V6_ROUTE_HASHED,
+ true);
+
+ return valid;
+}
+
+bool ipa_filter_map_valid(struct ipa *ipa, u32 filter_map)
+{
+ struct device *dev = &ipa->pdev->dev;
+ u32 count;
+
+ if (!filter_map) {
+ dev_err(dev, "at least one filtering endpoint is required\n");
+
+ return false;
+ }
+
+ count = hweight32(filter_map);
+ if (count > IPA_FILTER_COUNT_MAX) {
+ dev_err(dev, "too many filtering endpoints (%u, max %u)\n",
+ count, IPA_FILTER_COUNT_MAX);
+
+ return false;
+ }
+
+ return true;
+}
+
+/* Zero entry count means no table, so just return a 0 address */
+static dma_addr_t ipa_table_addr(struct ipa *ipa, bool filter_mask, u16 count)
+{
+ u32 skip;
+
+ if (!count)
+ return 0;
+
+ WARN_ON(count > max_t(u32, IPA_FILTER_COUNT_MAX, IPA_ROUTE_COUNT_MAX));
+
+ /* Skip over the zero rule and possibly the filter mask */
+ skip = filter_mask ? 1 : 2;
+
+ return ipa->table_addr + skip * sizeof(*ipa->table_virt);
+}
+
+static void ipa_table_reset_add(struct gsi_trans *trans, bool filter,
+ u16 first, u16 count, enum ipa_mem_id mem_id)
+{
+ struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
+ const struct ipa_mem *mem = ipa_mem_find(ipa, mem_id);
+ dma_addr_t addr;
+ u32 offset;
+ u16 size;
+
+ /* Nothing to do if the table memory region is empty */
+ if (!mem->size)
+ return;
+
+ if (filter)
+ first++; /* skip over bitmap */
+
+ offset = mem->offset + first * sizeof(__le64);
+ size = count * sizeof(__le64);
+ addr = ipa_table_addr(ipa, false, count);
+
+ ipa_cmd_dma_shared_mem_add(trans, offset, size, addr, true);
+}
+
+/* Reset entries in a single filter table belonging to either the AP or
+ * modem to refer to the zero entry. The memory region supplied will be
+ * for the IPv4 and IPv6 non-hashed and hashed filter tables.
+ */
+static int
+ipa_filter_reset_table(struct ipa *ipa, enum ipa_mem_id mem_id, bool modem)
+{
+ u32 ep_mask = ipa->filter_map;
+ u32 count = hweight32(ep_mask);
+ struct gsi_trans *trans;
+ enum gsi_ee_id ee_id;
+
+ trans = ipa_cmd_trans_alloc(ipa, count);
+ if (!trans) {
+ dev_err(&ipa->pdev->dev,
+ "no transaction for %s filter reset\n",
+ modem ? "modem" : "AP");
+ return -EBUSY;
+ }
+
+ ee_id = modem ? GSI_EE_MODEM : GSI_EE_AP;
+ while (ep_mask) {
+ u32 endpoint_id = __ffs(ep_mask);
+ struct ipa_endpoint *endpoint;
+
+ ep_mask ^= BIT(endpoint_id);
+
+ endpoint = &ipa->endpoint[endpoint_id];
+ if (endpoint->ee_id != ee_id)
+ continue;
+
+ ipa_table_reset_add(trans, true, endpoint_id, 1, mem_id);
+ }
+
+ gsi_trans_commit_wait(trans);
+
+ return 0;
+}
+
+/* Theoretically, each filter table could have more filter slots to
+ * update than the maximum number of commands in a transaction. So
+ * we do each table separately.
+ */
+static int ipa_filter_reset(struct ipa *ipa, bool modem)
+{
+ int ret;
+
+ ret = ipa_filter_reset_table(ipa, IPA_MEM_V4_FILTER, modem);
+ if (ret)
+ return ret;
+
+ ret = ipa_filter_reset_table(ipa, IPA_MEM_V6_FILTER, modem);
+ if (ret || !ipa_table_hash_support(ipa))
+ return ret;
+
+ ret = ipa_filter_reset_table(ipa, IPA_MEM_V4_FILTER_HASHED, modem);
+ if (ret)
+ return ret;
+
+ return ipa_filter_reset_table(ipa, IPA_MEM_V6_FILTER_HASHED, modem);
+}
+
+/* The AP routes and modem routes are each contiguous within the
+ * table. We can update each table with a single command, and we
+ * won't exceed the per-transaction command limit.
+ * */
+static int ipa_route_reset(struct ipa *ipa, bool modem)
+{
+ bool hash_support = ipa_table_hash_support(ipa);
+ struct gsi_trans *trans;
+ u16 first;
+ u16 count;
+
+ trans = ipa_cmd_trans_alloc(ipa, hash_support ? 4 : 2);
+ if (!trans) {
+ dev_err(&ipa->pdev->dev,
+ "no transaction for %s route reset\n",
+ modem ? "modem" : "AP");
+ return -EBUSY;
+ }
+
+ if (modem) {
+ first = IPA_ROUTE_MODEM_MIN;
+ count = IPA_ROUTE_MODEM_COUNT;
+ } else {
+ first = IPA_ROUTE_AP_MIN;
+ count = IPA_ROUTE_AP_COUNT;
+ }
+
+ ipa_table_reset_add(trans, false, first, count, IPA_MEM_V4_ROUTE);
+ ipa_table_reset_add(trans, false, first, count, IPA_MEM_V6_ROUTE);
+
+ if (hash_support) {
+ ipa_table_reset_add(trans, false, first, count,
+ IPA_MEM_V4_ROUTE_HASHED);
+ ipa_table_reset_add(trans, false, first, count,
+ IPA_MEM_V6_ROUTE_HASHED);
+ }
+
+ gsi_trans_commit_wait(trans);
+
+ return 0;
+}
+
+void ipa_table_reset(struct ipa *ipa, bool modem)
+{
+ struct device *dev = &ipa->pdev->dev;
+ const char *ee_name;
+ int ret;
+
+ ee_name = modem ? "modem" : "AP";
+
+ /* Report errors, but reset filter and route tables */
+ ret = ipa_filter_reset(ipa, modem);
+ if (ret)
+ dev_err(dev, "error %d resetting filter table for %s\n",
+ ret, ee_name);
+
+ ret = ipa_route_reset(ipa, modem);
+ if (ret)
+ dev_err(dev, "error %d resetting route table for %s\n",
+ ret, ee_name);
+}
+
+int ipa_table_hash_flush(struct ipa *ipa)
+{
+ const struct ipa_reg *reg;
+ struct gsi_trans *trans;
+ u32 offset;
+ u32 val;
+
+ if (!ipa_table_hash_support(ipa))
+ return 0;
+
+ trans = ipa_cmd_trans_alloc(ipa, 1);
+ if (!trans) {
+ dev_err(&ipa->pdev->dev, "no transaction for hash flush\n");
+ return -EBUSY;
+ }
+
+ reg = ipa_reg(ipa, FILT_ROUT_HASH_FLUSH);
+ offset = ipa_reg_offset(reg);
+
+ val = ipa_reg_bit(reg, IPV6_ROUTER_HASH);
+ val |= ipa_reg_bit(reg, IPV6_FILTER_HASH);
+ val |= ipa_reg_bit(reg, IPV4_ROUTER_HASH);
+ val |= ipa_reg_bit(reg, IPV4_FILTER_HASH);
+
+ ipa_cmd_register_write_add(trans, offset, val, val, false);
+
+ gsi_trans_commit_wait(trans);
+
+ return 0;
+}
+
+static void ipa_table_init_add(struct gsi_trans *trans, bool filter,
+ enum ipa_cmd_opcode opcode,
+ enum ipa_mem_id mem_id,
+ enum ipa_mem_id hash_mem_id)
+{
+ struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
+ const struct ipa_mem *hash_mem = ipa_mem_find(ipa, hash_mem_id);
+ const struct ipa_mem *mem = ipa_mem_find(ipa, mem_id);
+ dma_addr_t hash_addr;
+ dma_addr_t addr;
+ u32 zero_offset;
+ u16 hash_count;
+ u32 zero_size;
+ u16 hash_size;
+ u16 count;
+ u16 size;
+
+ /* Compute the number of table entries to initialize */
+ if (filter) {
+ /* The number of filtering endpoints determines number of
+ * entries in the filter table; we also add one more "slot"
+ * to hold the bitmap itself. The size of the hashed filter
+ * table is either the same as the non-hashed one, or zero.
+ */
+ count = 1 + hweight32(ipa->filter_map);
+ hash_count = hash_mem->size ? count : 0;
+ } else {
+ /* The size of a route table region determines the number
+ * of entries it has.
+ */
+ count = mem->size / sizeof(__le64);
+ hash_count = hash_mem->size / sizeof(__le64);
+ }
+ size = count * sizeof(__le64);
+ hash_size = hash_count * sizeof(__le64);
+
+ addr = ipa_table_addr(ipa, filter, count);
+ hash_addr = ipa_table_addr(ipa, filter, hash_count);
+
+ ipa_cmd_table_init_add(trans, opcode, size, mem->offset, addr,
+ hash_size, hash_mem->offset, hash_addr);
+ if (!filter)
+ return;
+
+ /* Zero the unused space in the filter table */
+ zero_offset = mem->offset + size;
+ zero_size = mem->size - size;
+ ipa_cmd_dma_shared_mem_add(trans, zero_offset, zero_size,
+ ipa->zero_addr, true);
+ if (!hash_size)
+ return;
+
+ /* Zero the unused space in the hashed filter table */
+ zero_offset = hash_mem->offset + hash_size;
+ zero_size = hash_mem->size - hash_size;
+ ipa_cmd_dma_shared_mem_add(trans, zero_offset, zero_size,
+ ipa->zero_addr, true);
+}
+
+int ipa_table_setup(struct ipa *ipa)
+{
+ struct gsi_trans *trans;
+
+ /* We will need at most 8 TREs:
+ * - IPv4:
+ * - One for route table initialization (non-hashed and hashed)
+ * - One for filter table initialization (non-hashed and hashed)
+ * - One to zero unused entries in the non-hashed filter table
+ * - One to zero unused entries in the hashed filter table
+ * - IPv6:
+ * - One for route table initialization (non-hashed and hashed)
+ * - One for filter table initialization (non-hashed and hashed)
+ * - One to zero unused entries in the non-hashed filter table
+ * - One to zero unused entries in the hashed filter table
+ * All platforms support at least 8 TREs in a transaction.
+ */
+ trans = ipa_cmd_trans_alloc(ipa, 8);
+ if (!trans) {
+ dev_err(&ipa->pdev->dev, "no transaction for table setup\n");
+ return -EBUSY;
+ }
+
+ ipa_table_init_add(trans, false, IPA_CMD_IP_V4_ROUTING_INIT,
+ IPA_MEM_V4_ROUTE, IPA_MEM_V4_ROUTE_HASHED);
+
+ ipa_table_init_add(trans, false, IPA_CMD_IP_V6_ROUTING_INIT,
+ IPA_MEM_V6_ROUTE, IPA_MEM_V6_ROUTE_HASHED);
+
+ ipa_table_init_add(trans, true, IPA_CMD_IP_V4_FILTER_INIT,
+ IPA_MEM_V4_FILTER, IPA_MEM_V4_FILTER_HASHED);
+
+ ipa_table_init_add(trans, true, IPA_CMD_IP_V6_FILTER_INIT,
+ IPA_MEM_V6_FILTER, IPA_MEM_V6_FILTER_HASHED);
+
+ gsi_trans_commit_wait(trans);
+
+ return 0;
+}
+
+/**
+ * ipa_filter_tuple_zero() - Zero an endpoint's hashed filter tuple
+ * @endpoint: Endpoint whose filter hash tuple should be zeroed
+ *
+ * Endpoint must be for the AP (not modem) and support filtering. Updates
+ * the filter hash values without changing route ones.
+ */
+static void ipa_filter_tuple_zero(struct ipa_endpoint *endpoint)
+{
+ u32 endpoint_id = endpoint->endpoint_id;
+ struct ipa *ipa = endpoint->ipa;
+ const struct ipa_reg *reg;
+ u32 offset;
+ u32 val;
+
+ reg = ipa_reg(ipa, ENDP_FILTER_ROUTER_HSH_CFG);
+
+ offset = ipa_reg_n_offset(reg, endpoint_id);
+ val = ioread32(endpoint->ipa->reg_virt + offset);
+
+ /* Zero all filter-related fields, preserving the rest */
+ val &= ~ipa_reg_fmask(reg, FILTER_HASH_MSK_ALL);
+
+ iowrite32(val, endpoint->ipa->reg_virt + offset);
+}
+
+/* Configure a hashed filter table; there is no ipa_filter_deconfig() */
+static void ipa_filter_config(struct ipa *ipa, bool modem)
+{
+ enum gsi_ee_id ee_id = modem ? GSI_EE_MODEM : GSI_EE_AP;
+ u32 ep_mask = ipa->filter_map;
+
+ if (!ipa_table_hash_support(ipa))
+ return;
+
+ while (ep_mask) {
+ u32 endpoint_id = __ffs(ep_mask);
+ struct ipa_endpoint *endpoint;
+
+ ep_mask ^= BIT(endpoint_id);
+
+ endpoint = &ipa->endpoint[endpoint_id];
+ if (endpoint->ee_id == ee_id)
+ ipa_filter_tuple_zero(endpoint);
+ }
+}
+
+static bool ipa_route_id_modem(u32 route_id)
+{
+ return route_id >= IPA_ROUTE_MODEM_MIN &&
+ route_id <= IPA_ROUTE_MODEM_MIN + IPA_ROUTE_MODEM_COUNT - 1;
+}
+
+/**
+ * ipa_route_tuple_zero() - Zero a hashed route table entry tuple
+ * @ipa: IPA pointer
+ * @route_id: Route table entry whose hash tuple should be zeroed
+ *
+ * Updates the route hash values without changing filter ones.
+ */
+static void ipa_route_tuple_zero(struct ipa *ipa, u32 route_id)
+{
+ const struct ipa_reg *reg;
+ u32 offset;
+ u32 val;
+
+ reg = ipa_reg(ipa, ENDP_FILTER_ROUTER_HSH_CFG);
+ offset = ipa_reg_n_offset(reg, route_id);
+
+ val = ioread32(ipa->reg_virt + offset);
+
+ /* Zero all route-related fields, preserving the rest */
+ val &= ~ipa_reg_fmask(reg, ROUTER_HASH_MSK_ALL);
+
+ iowrite32(val, ipa->reg_virt + offset);
+}
+
+/* Configure a hashed route table; there is no ipa_route_deconfig() */
+static void ipa_route_config(struct ipa *ipa, bool modem)
+{
+ u32 route_id;
+
+ if (!ipa_table_hash_support(ipa))
+ return;
+
+ for (route_id = 0; route_id < IPA_ROUTE_COUNT_MAX; route_id++)
+ if (ipa_route_id_modem(route_id) == modem)
+ ipa_route_tuple_zero(ipa, route_id);
+}
+
+/* Configure a filter and route tables; there is no ipa_table_deconfig() */
+void ipa_table_config(struct ipa *ipa)
+{
+ ipa_filter_config(ipa, false);
+ ipa_filter_config(ipa, true);
+ ipa_route_config(ipa, false);
+ ipa_route_config(ipa, true);
+}
+
+/*
+ * Initialize a coherent DMA allocation containing initialized filter and
+ * route table data. This is used when initializing or resetting the IPA
+ * filter or route table.
+ *
+ * The first entry in a filter table contains a bitmap indicating which
+ * endpoints contain entries in the table. In addition to that first entry,
+ * there are at most IPA_FILTER_COUNT_MAX entries that follow. Filter table
+ * entries are 64 bits wide, and (other than the bitmap) contain the DMA
+ * address of a filter rule. A "zero rule" indicates no filtering, and
+ * consists of 64 bits of zeroes. When a filter table is initialized (or
+ * reset) its entries are made to refer to the zero rule.
+ *
+ * Each entry in a route table is the DMA address of a routing rule. For
+ * routing there is also a 64-bit "zero rule" that means no routing, and
+ * when a route table is initialized or reset, its entries are made to refer
+ * to the zero rule. The zero rule is shared for route and filter tables.
+ *
+ * Note that the IPA hardware requires a filter or route rule address to be
+ * aligned on a 128 byte boundary. The coherent DMA buffer we allocate here
+ * has a minimum alignment, and we place the zero rule at the base of that
+ * allocated space. In ipa_table_init() we verify the minimum DMA allocation
+ * meets our requirement.
+ *
+ * +-------------------+
+ * --> | zero rule |
+ * / |-------------------|
+ * | | filter mask |
+ * |\ |-------------------|
+ * | ---- zero rule address | \
+ * |\ |-------------------| |
+ * | ---- zero rule address | | IPA_FILTER_COUNT_MAX
+ * | |-------------------| > or IPA_ROUTE_COUNT_MAX,
+ * | ... | whichever is greater
+ * \ |-------------------| |
+ * ---- zero rule address | /
+ * +-------------------+
+ */
+int ipa_table_init(struct ipa *ipa)
+{
+ u32 count = max_t(u32, IPA_FILTER_COUNT_MAX, IPA_ROUTE_COUNT_MAX);
+ struct device *dev = &ipa->pdev->dev;
+ dma_addr_t addr;
+ __le64 le_addr;
+ __le64 *virt;
+ size_t size;
+
+ ipa_table_validate_build();
+
+ /* The IPA hardware requires route and filter table rules to be
+ * aligned on a 128-byte boundary. We put the "zero rule" at the
+ * base of the table area allocated here. The DMA address returned
+ * by dma_alloc_coherent() is guaranteed to be a power-of-2 number
+ * of pages, which satisfies the rule alignment requirement.
+ */
+ size = IPA_ZERO_RULE_SIZE + (1 + count) * sizeof(__le64);
+ virt = dma_alloc_coherent(dev, size, &addr, GFP_KERNEL);
+ if (!virt)
+ return -ENOMEM;
+
+ ipa->table_virt = virt;
+ ipa->table_addr = addr;
+
+ /* First slot is the zero rule */
+ *virt++ = 0;
+
+ /* Next is the filter table bitmap. The "soft" bitmap value
+ * must be converted to the hardware representation by shifting
+ * it left one position. (Bit 0 repesents global filtering,
+ * which is possible but not used.)
+ */
+ *virt++ = cpu_to_le64((u64)ipa->filter_map << 1);
+
+ /* All the rest contain the DMA address of the zero rule */
+ le_addr = cpu_to_le64(addr);
+ while (count--)
+ *virt++ = le_addr;
+
+ return 0;
+}
+
+void ipa_table_exit(struct ipa *ipa)
+{
+ u32 count = max_t(u32, 1 + IPA_FILTER_COUNT_MAX, IPA_ROUTE_COUNT_MAX);
+ struct device *dev = &ipa->pdev->dev;
+ size_t size;
+
+ size = IPA_ZERO_RULE_SIZE + (1 + count) * sizeof(__le64);
+
+ dma_free_coherent(dev, size, ipa->table_virt, ipa->table_addr);
+ ipa->table_addr = 0;
+ ipa->table_virt = NULL;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-05 12:39:59 +0000