+From: Thomas Hebb <tommyhebb@gmail.com>
+Subject: [PATCH] ath10k: search all IEs for variant before falling back
+Date: Wed, 21 Feb 2018 11:43:39 -0500
+
+commit f2593cb1b291 ("ath10k: Search SMBIOS for OEM board file
+extension") added a feature to ath10k that allows Board Data File
+(BDF) conflicts between multiple devices that use the same device IDs
+but have different calibration requirements to be resolved by allowing
+a "variant" string to be stored in SMBIOS [and later device tree, added
+by commit d06f26c5c8a4 ("ath10k: search DT for qcom,ath10k-calibration-
+variant")] that gets appended to the ID stored in board-2.bin.
+
+This original patch had a regression, however. Namely that devices with
+a variant present in SMBIOS that didn't need custom BDFs could no longer
+find the default BDF, which has no variant appended. The patch was
+reverted and re-applied with a fix for this issue in commit 1657b8f84ed9
+("search SMBIOS for OEM board file extension").
+
+But the fix to fall back to a default BDF introduced another issue: the
+driver currently parses IEs in board-2.bin one by one, and for each one
+it first checks to see if it matches the ID with the variant appended.
+If it doesn't, it checks to see if it matches the "fallback" ID with no
+variant. If a matching BDF is found at any point during this search, the
+search is terminated and that BDF is used. The issue is that it's very
+possible (and is currently the case for board-2.bin files present in the
+ath10k-firmware repository) for the default BDF to occur in an earlier
+IE than the variant-specific BDF. In this case, the current code will
+happily choose the default BDF even though a better-matching BDF is
+present later in the file.
+
+This patch fixes the issue by first searching the entire file for the ID
+with variant, and searching for the fallback ID only if that search
+fails. It also includes some code cleanup in the area, as
+ath10k_core_fetch_board_data_api_n() no longer does its own string
+mangling to remove the variant from an ID, instead leaving that job to a
+new flag passed to ath10k_core_create_board_name().
+
+I've tested this patch on a QCA4019 and verified that the driver behaves
+correctly for 1) both fallback and variant BDFs present, 2) only fallback
+BDF present, and 3) no matching BDFs present.
+
+Fixes: 1657b8f84ed9 ("ath10k: search SMBIOS for OEM board file extension")
+Signed-off-by: Thomas Hebb <tommyhebb@gmail.com>
+---
+ drivers/net/wireless/ath/ath10k/core.c | 134 ++++++++++++++++++---------------
+ 1 file changed, 72 insertions(+), 62 deletions(-)
+
+--- a/drivers/net/wireless/ath/ath10k/core.c
++++ b/drivers/net/wireless/ath/ath10k/core.c
+@@ -1129,14 +1129,61 @@ out:
+ return ret;
+ }
+
++static int ath10k_core_search_bd(struct ath10k *ar,
++ const char *boardname,
++ const u8 *data,
++ size_t len)
++{
++ size_t ie_len;
++ struct ath10k_fw_ie *hdr;
++ int ret = -ENOENT, ie_id;
++
++ while (len > sizeof(struct ath10k_fw_ie)) {
++ hdr = (struct ath10k_fw_ie *)data;
++ ie_id = le32_to_cpu(hdr->id);
++ ie_len = le32_to_cpu(hdr->len);
++
++ len -= sizeof(*hdr);
++ data = hdr->data;
++
++ if (len < ALIGN(ie_len, 4)) {
++ ath10k_err(ar, "invalid length for board ie_id %d ie_len %zu len %zu\n",
++ ie_id, ie_len, len);
++ return -EINVAL;
++ }
++
++ switch (ie_id) {
++ case ATH10K_BD_IE_BOARD:
++ ret = ath10k_core_parse_bd_ie_board(ar, data, ie_len,
++ boardname);
++ if (ret == -ENOENT)
++ /* no match found, continue */
++ break;
++
++ /* either found or error, so stop searching */
++ goto out;
++ }
++
++ /* jump over the padding */
++ ie_len = ALIGN(ie_len, 4);
++
++ len -= ie_len;
++ data += ie_len;
++ }
++
++out:
++ /* return result of parse_bd_ie_board() or -ENOENT */
++ return ret;
++}
++
+ static int ath10k_core_fetch_board_data_api_n(struct ath10k *ar,
+ const char *boardname,
++ const char *fallback_boardname,
+ const char *filename)
+ {
+- size_t len, magic_len, ie_len;
+- struct ath10k_fw_ie *hdr;
++ size_t len, magic_len;
+ const u8 *data;
+- int ret, ie_id;
++ int ret;
+
+ ar->normal_mode_fw.board = ath10k_fetch_fw_file(ar,
+ ar->hw_params.fw.dir,
+@@ -1174,69 +1221,23 @@ static int ath10k_core_fetch_board_data_
+ data += magic_len;
+ len -= magic_len;
+
+- while (len > sizeof(struct ath10k_fw_ie)) {
+- hdr = (struct ath10k_fw_ie *)data;
+- ie_id = le32_to_cpu(hdr->id);
+- ie_len = le32_to_cpu(hdr->len);
+-
+- len -= sizeof(*hdr);
+- data = hdr->data;
+-
+- if (len < ALIGN(ie_len, 4)) {
+- ath10k_err(ar, "invalid length for board ie_id %d ie_len %zu len %zu\n",
+- ie_id, ie_len, len);
+- ret = -EINVAL;
+- goto err;
+- }
++ /* attempt to find boardname in the IE list */
++ ret = ath10k_core_search_bd(ar, boardname, data, len);
+
+- switch (ie_id) {
+- case ATH10K_BD_IE_BOARD:
+- ret = ath10k_core_parse_bd_ie_board(ar, data, ie_len,
+- boardname);
+- if (ret == -ENOENT && ar->id.bdf_ext[0] != '\0') {
+- /* try default bdf if variant was not found */
+- char *s, *v = ",variant=";
+- char boardname2[100];
+-
+- strlcpy(boardname2, boardname,
+- sizeof(boardname2));
+-
+- s = strstr(boardname2, v);
+- if (s)
+- *s = '\0'; /* strip ",variant=%s" */
+-
+- ret = ath10k_core_parse_bd_ie_board(ar, data,
+- ie_len,
+- boardname2);
+- }
++ /* if we didn't find it and have a fallback name, try that */
++ if (ret == -ENOENT && fallback_boardname)
++ ret = ath10k_core_search_bd(ar, fallback_boardname, data, len);
+
+- if (ret == -ENOENT)
+- /* no match found, continue */
+- break;
+- else if (ret)
+- /* there was an error, bail out */
+- goto err;
+-
+- /* board data found */
+- goto out;
+- }
+-
+- /* jump over the padding */
+- ie_len = ALIGN(ie_len, 4);
+-
+- len -= ie_len;
+- data += ie_len;
+- }
+-
+-out:
+- if (!ar->normal_mode_fw.board_data || !ar->normal_mode_fw.board_len) {
++ if (ret == -ENOENT) {
+ ath10k_err(ar,
+ "failed to fetch board data for %s from %s/%s\n",
+ boardname, ar->hw_params.fw.dir, filename);
+ ret = -ENODATA;
+- goto err;
+ }
+
++ if (ret)
++ goto err;
++
+ return 0;
+
+ err:
+@@ -1245,12 +1246,12 @@ err:
+ }
+
+ static int ath10k_core_create_board_name(struct ath10k *ar, char *name,
+- size_t name_len)
++ size_t name_len, bool with_variant)
+ {
+ /* strlen(',variant=') + strlen(ar->id.bdf_ext) */
+ char variant[9 + ATH10K_SMBIOS_BDF_EXT_STR_LENGTH] = { 0 };
+
+- if (ar->id.bdf_ext[0] != '\0')
++ if (with_variant && ar->id.bdf_ext[0] != '\0')
+ scnprintf(variant, sizeof(variant), ",variant=%s",
+ ar->id.bdf_ext);
+
+@@ -1276,17 +1277,26 @@ out:
+
+ static int ath10k_core_fetch_board_file(struct ath10k *ar)
+ {
+- char boardname[100];
++ char boardname[100], fallback_boardname[100];
+ int ret;
+
+- ret = ath10k_core_create_board_name(ar, boardname, sizeof(boardname));
++ ret = ath10k_core_create_board_name(ar, boardname,
++ sizeof(boardname), true);
+ if (ret) {
+ ath10k_err(ar, "failed to create board name: %d", ret);
+ return ret;
+ }
+
++ ret = ath10k_core_create_board_name(ar, fallback_boardname,
++ sizeof(boardname), false);
++ if (ret) {
++ ath10k_err(ar, "failed to create fallback board name: %d", ret);
++ return ret;
++ }
++
+ ar->bd_api = 2;
+ ret = ath10k_core_fetch_board_data_api_n(ar, boardname,
++ fallback_boardname,
+ ATH10K_BOARD_API2_FILE);
+ if (!ret)
+ goto success;
projects / openwrt / openwrt.git / commitdiff