// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/* Copyright (C) 2015-2017 Netronome Systems, Inc. */
/* Parse the hwinfo table that the ARM firmware builds in the ARM scratch SRAM
* after chip reset.
*
* Examples of the fields:
* me.count = 40
* me.mask = 0x7f_ffff_ffff
*
* me.count is the total number of MEs on the system.
* me.mask is the bitmask of MEs that are available for application usage.
*
* (ie, in this example, ME 39 has been reserved by boardconfig.)
*/
#include <asm/byteorder.h>
#include <linux/unaligned.h>
#include <linux/delay.h>
#include <linux/log2.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#define NFP_SUBSYS "nfp_hwinfo"
#include "crc32.h"
#include "nfp.h"
#include "nfp_cpp.h"
#include "nfp6000/nfp6000.h"
#define HWINFO_SIZE_MIN 0x100
#define HWINFO_WAIT 20 /* seconds */
/* The Hardware Info Table defines the properties of the system.
*
* HWInfo v1 Table (fixed size)
*
* 0x0000: u32 version Hardware Info Table version (1.0)
* 0x0004: u32 size Total size of the table, including
* the CRC32 (IEEE 802.3)
* 0x0008: u32 jumptab Offset of key/value table
* 0x000c: u32 keys Total number of keys in the key/value table
* NNNNNN: Key/value jump table and string data
* (size - 4): u32 crc32 CRC32 (same as IEEE 802.3, POSIX csum, etc)
* CRC32("",0) = ~0, CRC32("a",1) = 0x48C279FE
*
* HWInfo v2 Table (variable size)
*
* 0x0000: u32 version Hardware Info Table version (2.0)
* 0x0004: u32 size Current size of the data area, excluding CRC32
* 0x0008: u32 limit Maximum size of the table
* 0x000c: u32 reserved Unused, set to zero
* NNNNNN: Key/value data
* (size - 4): u32 crc32 CRC32 (same as IEEE 802.3, POSIX csum, etc)
* CRC32("",0) = ~0, CRC32("a",1) = 0x48C279FE
*
* If the HWInfo table is in the process of being updated, the low bit
* of version will be set.
*
* HWInfo v1 Key/Value Table
* -------------------------
*
* The key/value table is a set of offsets to ASCIIZ strings which have
* been strcmp(3) sorted (yes, please use bsearch(3) on the table).
*
* All keys are guaranteed to be unique.
*
* N+0: u32 key_1 Offset to the first key
* N+4: u32 val_1 Offset to the first value
* N+8: u32 key_2 Offset to the second key
* N+c: u32 val_2 Offset to the second value
* ...
*
* HWInfo v2 Key/Value Table
* -------------------------
*
* Packed UTF8Z strings, ie 'key1\000value1\000key2\000value2\000'
*
* Unsorted.
*/
#define NFP_HWINFO_VERSION_1 ('H' << 24 | 'I' << 16 | 1 << 8 | 0 << 1 | 0)
#define NFP_HWINFO_VERSION_2 ('H' << 24 | 'I' << 16 | 2 << 8 | 0 << 1 | 0)
#define NFP_HWINFO_VERSION_UPDATING BIT(0)
struct nfp_hwinfo {
u8 start[0];
__le32 version;
__le32 size;
/* v2 specific fields */
__le32 limit;
__le32 resv;
char data[];
};
static bool nfp_hwinfo_is_updating(struct nfp_hwinfo *hwinfo)
{
return le32_to_cpu(hwinfo->version) & NFP_HWINFO_VERSION_UPDATING;
}
static int
hwinfo_db_walk(struct nfp_cpp *cpp, struct nfp_hwinfo *hwinfo, u32 size)
{
const char *key, *val, *end = hwinfo->data + size;
for (key = hwinfo->data; *key && key < end;
key = val + strlen(val) + 1) {
val = key + strlen(key) + 1;
if (val >= end) {
nfp_warn(cpp, "Bad HWINFO - overflowing key\n");
return -EINVAL;
}
if (val + strlen(val) + 1 > end) {
nfp_warn(cpp, "Bad HWINFO - overflowing value\n");
return -EINVAL;
}
}
return 0;
}
static int
hwinfo_db_validate(struct nfp_cpp *cpp, struct nfp_hwinfo *db, u32 len)
{
u32 size, crc;
size = le32_to_cpu(db->size);
if (size > len) {
nfp_err(cpp, "Unsupported hwinfo size %u > %u\n", size, len);
return -EINVAL;
}
size -= sizeof(u32);
crc = crc32_posix(db, size);
if (crc != get_unaligned_le32(db->start + size)) {
nfp_err(cpp, "Corrupt hwinfo table (CRC mismatch), calculated 0x%x, expected 0x%x\n",
crc, get_unaligned_le32(db->start + size));
return -EINVAL;
}
return hwinfo_db_walk(cpp, db, size);
}
static struct nfp_hwinfo *
hwinfo_try_fetch(struct nfp_cpp *cpp, size_t *cpp_size)
{
struct nfp_hwinfo *header;
struct nfp_resource *res;
u64 cpp_addr;
u32 cpp_id;
int err;
u8 *db;
res = nfp_resource_acquire(cpp, NFP_RESOURCE_NFP_HWINFO);
if (!IS_ERR(res)) {
cpp_id = nfp_resource_cpp_id(res);
cpp_addr = nfp_resource_address(res);
*cpp_size = nfp_resource_size(res);
nfp_resource_release(res);
if (*cpp_size < HWINFO_SIZE_MIN)
return NULL;
} else if (PTR_ERR(res) == -ENOENT) {
/* Try getting the HWInfo table from the 'classic' location */
cpp_id = NFP_CPP_ISLAND_ID(NFP_CPP_TARGET_MU,
NFP_CPP_ACTION_RW, 0, 1);
cpp_addr = 0x30000;
*cpp_size = 0x0e000;
} else {
return NULL;
}
db = kmalloc(*cpp_size + 1, GFP_KERNEL);
if (!db)
return NULL;
err = nfp_cpp_read(cpp, cpp_id, cpp_addr, db, *cpp_size);
if (err != *cpp_size)
goto exit_free;
header = (void *)db;
if (nfp_hwinfo_is_updating(header))
goto exit_free;
if (le32_to_cpu(header->version) != NFP_HWINFO_VERSION_2) {
nfp_err(cpp, "Unknown HWInfo version: 0x%08x\n",
le32_to_cpu(header->version));
goto exit_free;
}
/* NULL-terminate for safety */
db[*cpp_size] = '\0';
return (void *)db;
exit_free:
kfree(db);
return NULL;
}
static struct nfp_hwinfo *hwinfo_fetch(struct nfp_cpp *cpp, size_t *hwdb_size)
{
const unsigned long wait_until = jiffies + HWINFO_WAIT * HZ;
struct nfp_hwinfo *db;
int err;
for (;;) {
const unsigned long start_time = jiffies;
db = hwinfo_try_fetch(cpp, hwdb_size);
if (db)
return db;
err = msleep_interruptible(100);
if (err || time_after(start_time, wait_until)) {
nfp_err(cpp, "NFP access error\n");
return NULL;
}
}
}
struct nfp_hwinfo *nfp_hwinfo_read(struct nfp_cpp *cpp)
{
struct nfp_hwinfo *db;
size_t hwdb_size = 0;
int err;
db = hwinfo_fetch(cpp, &hwdb_size);
if (!db)
return NULL;
err = hwinfo_db_validate(cpp, db, hwdb_size);
if (err) {
kfree(db);
return NULL;
}
return db;
}
/**
* nfp_hwinfo_lookup() - Find a value in the HWInfo table by name
* @hwinfo: NFP HWinfo table
* @lookup: HWInfo name to search for
*
* Return: Value of the HWInfo name, or NULL
*/
const char *nfp_hwinfo_lookup(struct nfp_hwinfo *hwinfo, const char *lookup)
{
const char *key, *val, *end;
if (!hwinfo || !lookup)
return NULL;
end = hwinfo->data + le32_to_cpu(hwinfo->size) - sizeof(u32);
for (key = hwinfo->data; *key && key < end;
key = val + strlen(val) + 1) {
val = key + strlen(key) + 1;
if (strcmp(key, lookup) == 0)
return val;
}
return NULL;
}
char *nfp_hwinfo_get_packed_strings(struct nfp_hwinfo *hwinfo)
{
return hwinfo->data;
}
u32 nfp_hwinfo_get_packed_str_size(struct nfp_hwinfo *hwinfo)
{
return le32_to_cpu(hwinfo->size) - sizeof(u32);
}
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