[PATCH net-next 7/7] net: ipa: kill IPA_TABLE_ENTRY_SIZE

From: Alex Elder
Date: Sun Mar 28 2021 - 13:34:37 EST


Entries in an IPA route or filter table are 64-bit little-endian
addresses, each of which refers to a routing or filtering rule.

The format of these table slots are fixed, but IPA_TABLE_ENTRY_SIZE
is used to define their size. This symbol doesn't really add value,
and I think it unnecessarily obscures what a table entry *is*.

So get rid of IPA_TABLE_ENTRY_SIZE, and just use sizeof(__le64) in
its place throughout the code.

Update the comments in "ipa_table.c" to provide a little better
explanation of these table slots.

Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
---
drivers/net/ipa/ipa_cmd.c | 2 +-
drivers/net/ipa/ipa_qmi.c | 10 +++----
drivers/net/ipa/ipa_table.c | 59 +++++++++++++++++++++----------------
drivers/net/ipa/ipa_table.h | 3 --
4 files changed, 39 insertions(+), 35 deletions(-)

diff --git a/drivers/net/ipa/ipa_cmd.c b/drivers/net/ipa/ipa_cmd.c
index 2ac6dd8413dee..525cdf28d9ea7 100644
--- a/drivers/net/ipa/ipa_cmd.c
+++ b/drivers/net/ipa/ipa_cmd.c
@@ -153,7 +153,7 @@ static void ipa_cmd_validate_build(void)
* 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_SIZE (TABLE_COUNT_MAX * sizeof(__le64))
#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));
diff --git a/drivers/net/ipa/ipa_qmi.c b/drivers/net/ipa/ipa_qmi.c
index ccdb4a6a4c75b..593665efbcf99 100644
--- a/drivers/net/ipa/ipa_qmi.c
+++ b/drivers/net/ipa/ipa_qmi.c
@@ -308,12 +308,12 @@ init_modem_driver_req(struct ipa_qmi *ipa_qmi)
mem = &ipa->mem[IPA_MEM_V4_ROUTE];
req.v4_route_tbl_info_valid = 1;
req.v4_route_tbl_info.start = ipa->mem_offset + mem->offset;
- req.v4_route_tbl_info.count = mem->size / IPA_TABLE_ENTRY_SIZE;
+ req.v4_route_tbl_info.count = mem->size / sizeof(__le64);

mem = &ipa->mem[IPA_MEM_V6_ROUTE];
req.v6_route_tbl_info_valid = 1;
req.v6_route_tbl_info.start = ipa->mem_offset + mem->offset;
- req.v6_route_tbl_info.count = mem->size / IPA_TABLE_ENTRY_SIZE;
+ req.v6_route_tbl_info.count = mem->size / sizeof(__le64);

mem = &ipa->mem[IPA_MEM_V4_FILTER];
req.v4_filter_tbl_start_valid = 1;
@@ -352,8 +352,7 @@ init_modem_driver_req(struct ipa_qmi *ipa_qmi)
req.v4_hash_route_tbl_info_valid = 1;
req.v4_hash_route_tbl_info.start =
ipa->mem_offset + mem->offset;
- req.v4_hash_route_tbl_info.count =
- mem->size / IPA_TABLE_ENTRY_SIZE;
+ req.v4_hash_route_tbl_info.count = mem->size / sizeof(__le64);
}

mem = &ipa->mem[IPA_MEM_V6_ROUTE_HASHED];
@@ -361,8 +360,7 @@ init_modem_driver_req(struct ipa_qmi *ipa_qmi)
req.v6_hash_route_tbl_info_valid = 1;
req.v6_hash_route_tbl_info.start =
ipa->mem_offset + mem->offset;
- req.v6_hash_route_tbl_info.count =
- mem->size / IPA_TABLE_ENTRY_SIZE;
+ req.v6_hash_route_tbl_info.count = mem->size / sizeof(__le64);
}

mem = &ipa->mem[IPA_MEM_V4_FILTER_HASHED];
diff --git a/drivers/net/ipa/ipa_table.c b/drivers/net/ipa/ipa_table.c
index d9538661755f4..401b568df6a34 100644
--- a/drivers/net/ipa/ipa_table.c
+++ b/drivers/net/ipa/ipa_table.c
@@ -27,28 +27,38 @@
/**
* DOC: IPA Filter and Route Tables
*
- * The IPA has tables defined in its local shared memory that define filter
- * and routing rules. Each entry in these tables contains a 64-bit DMA
- * address that refers to DRAM (system memory) containing a rule definition.
+ * 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. Separate tables (both filter and route)
- * used for IPv4 and IPv6. Additionally, there can be hashed filter or
- * route tables, which are used when a hash of message metadata matches.
- * Hashed operation is not supported by all IPA hardware.
+ * 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 entry in a
+ * 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. a DMA address referring to a rule) for endpoint 0 in the
- * table. Bit 2, if set, indicates there is an entry for endpoint 1,
- * 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.
+ * 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
@@ -122,8 +132,7 @@ static void ipa_table_validate_build(void)
* code in ipa_table_init() uses a pointer to __le64 to
* initialize tables.
*/
- BUILD_BUG_ON(sizeof(dma_addr_t) > IPA_TABLE_ENTRY_SIZE);
- BUILD_BUG_ON(sizeof(__le64) != IPA_TABLE_ENTRY_SIZE);
+ 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()
@@ -154,7 +163,7 @@ ipa_table_valid_one(struct ipa *ipa, bool route, bool ipv6, bool hashed)
else
mem = hashed ? &ipa->mem[IPA_MEM_V4_ROUTE_HASHED]
: &ipa->mem[IPA_MEM_V4_ROUTE];
- size = IPA_ROUTE_COUNT_MAX * IPA_TABLE_ENTRY_SIZE;
+ size = IPA_ROUTE_COUNT_MAX * sizeof(__le64);
} else {
if (ipv6)
mem = hashed ? &ipa->mem[IPA_MEM_V6_FILTER_HASHED]
@@ -162,7 +171,7 @@ ipa_table_valid_one(struct ipa *ipa, bool route, bool ipv6, bool hashed)
else
mem = hashed ? &ipa->mem[IPA_MEM_V4_FILTER_HASHED]
: &ipa->mem[IPA_MEM_V4_FILTER];
- size = (1 + IPA_FILTER_COUNT_MAX) * IPA_TABLE_ENTRY_SIZE;
+ size = (1 + IPA_FILTER_COUNT_MAX) * sizeof(__le64);
}

if (!ipa_cmd_table_valid(ipa, mem, route, ipv6, hashed))
@@ -261,8 +270,8 @@ static void ipa_table_reset_add(struct gsi_trans *trans, bool filter,
if (filter)
first++; /* skip over bitmap */

- offset = mem->offset + first * IPA_TABLE_ENTRY_SIZE;
- size = count * IPA_TABLE_ENTRY_SIZE;
+ 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);
@@ -444,11 +453,11 @@ static void ipa_table_init_add(struct gsi_trans *trans, bool filter,
count = hweight32(ipa->filter_map);
hash_count = hash_mem->size ? count : 0;
} else {
- count = mem->size / IPA_TABLE_ENTRY_SIZE;
- hash_count = hash_mem->size / IPA_TABLE_ENTRY_SIZE;
+ count = mem->size / sizeof(__le64);
+ hash_count = hash_mem->size / sizeof(__le64);
}
- size = count * IPA_TABLE_ENTRY_SIZE;
- hash_size = hash_count * IPA_TABLE_ENTRY_SIZE;
+ 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);
@@ -655,7 +664,7 @@ int ipa_table_init(struct ipa *ipa)
* 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) * IPA_TABLE_ENTRY_SIZE;
+ size = IPA_ZERO_RULE_SIZE + (1 + count) * sizeof(__le64);
virt = dma_alloc_coherent(dev, size, &addr, GFP_KERNEL);
if (!virt)
return -ENOMEM;
@@ -687,7 +696,7 @@ void ipa_table_exit(struct ipa *ipa)
struct device *dev = &ipa->pdev->dev;
size_t size;

- size = IPA_ZERO_RULE_SIZE + (1 + count) * IPA_TABLE_ENTRY_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;
diff --git a/drivers/net/ipa/ipa_table.h b/drivers/net/ipa/ipa_table.h
index e14108ed62bdd..018045b95aad8 100644
--- a/drivers/net/ipa/ipa_table.h
+++ b/drivers/net/ipa/ipa_table.h
@@ -10,9 +10,6 @@

struct ipa;

-/* The size of a filter or route table entry */
-#define IPA_TABLE_ENTRY_SIZE sizeof(__le64) /* Holds a physical address */
-
/* The maximum number of filter table entries (IPv4, IPv6; hashed or not) */
#define IPA_FILTER_COUNT_MAX 14

--
2.27.0