ath10k-ct: search DT for BDF variant info

Board Data File (BDF) is loaded upon driver boot-up procedure. The right
board data file is identified on QCA4019 using bus, bmi-chip-id and
bmi-board-id.

The problem, however, can occur when the (default) board data file cannot
fulfill the vendor requirements and it is necessary to use a different
board data file.

This problem was solved for SMBIOS by adding a special SMBIOS type 0xF8.
Something similar has to be provided for systems without SMBIOS but with
device trees. No solution was specified by QCA and therefore a new one has
to be found for ath10k.

The device tree requires addition strings to define the variant name

    wifi@a000000 {
    	status = "okay";
    	qcom,ath10k-calibration-variant = "RT-AC58U";
    };

    wifi@a800000 {
    	status = "okay";
    	qcom,ath10k-calibration-variant = "RT-AC58U";
    };

This would create the boarddata identifiers for the board-2.bin search

 *  bus=ahb,bmi-chip-id=0,bmi-board-id=16,variant=RT-AC58U
 *  bus=ahb,bmi-chip-id=0,bmi-board-id=17,variant=RT-AC58U

Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
(cherry picked from commit 1c01e02575bd2af96741ba79ed12004fdfb15544)

3 files changed, 363 insertions, 1 deletions

diff --git a/package/kernel/ath10k-ct/Makefile b/package/kernel/ath10k-ct/Makefile
index 9c69dee72f..097500ebb7 100644
--- a/package/kernel/ath10k-ct/Makefile
+++ b/package/kernel/ath10k-ct/Makefile
@@ -1,7 +1,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=ath10k-ct
-PKG_RELEASE=2
+PKG_RELEASE=3
 
 PKG_LICENSE:=GPLv2
 PKG_LICENSE_FILES:=
diff --git a/package/kernel/ath10k-ct/patches/081-ath10k-calibration-variant.patch b/package/kernel/ath10k-ct/patches/081-ath10k-calibration-variant.patch
new file mode 100644
index 0000000000..d51451b596
--- /dev/null
+++ b/package/kernel/ath10k-ct/patches/081-ath10k-calibration-variant.patch
@@ -0,0 +1,113 @@
+From d06f26c5c8a41f246a9c40862a77a55725cedbd3 Mon Sep 17 00:00:00 2001
+From: Sven Eckelmann <sven.eckelmann@openmesh.com>
+Date: Fri, 8 Dec 2017 11:37:42 +0100
+Subject: ath10k: search DT for qcom,ath10k-calibration-variant
+
+Board Data File (BDF) is loaded upon driver boot-up procedure. The right
+board data file is identified on QCA4019 using bus, bmi-chip-id and
+bmi-board-id.
+
+The problem, however, can occur when the (default) board data file cannot
+fulfill with the vendor requirements and it is necessary to use a different
+board data file.
+
+This problem was solved for SMBIOS by adding a special SMBIOS type 0xF8.
+Something similar has to be provided for systems without SMBIOS but with
+device trees. No solution was specified by QCA and therefore a new one has
+to be found for ath10k.
+
+The device tree requires addition strings to define the variant name
+
+    wifi@a000000 {
+    	status = "okay";
+    	qcom,ath10k-calibration-variant = "RT-AC58U";
+    };
+
+    wifi@a800000 {
+    	status = "okay";
+    	qcom,ath10k-calibration-variant = "RT-AC58U";
+    };
+
+This would create the boarddata identifiers for the board-2.bin search
+
+ *  bus=ahb,bmi-chip-id=0,bmi-board-id=16,variant=RT-AC58U
+ *  bus=ahb,bmi-chip-id=0,bmi-board-id=17,variant=RT-AC58U
+
+Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>
+Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
+
+Origin: upstream, https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d06f26c5c8a41f246a9c40862a77a55725cedbd3
+---
+ ath10k-4.13/core.c | 40 ++++++++++++++++++++++++++++------
+ 1 file changed, 33 insertions(+), 7 deletions(-)
+
+--- a/ath10k-4.13/core.c
++++ b/ath10k-4.13/core.c
+@@ -889,6 +889,28 @@ static int ath10k_core_check_smbios(stru
+ 	return 0;
+ }
+ 
++static int ath10k_core_check_dt(struct ath10k *ar)
++{
++	struct device_node *node;
++	const char *variant = NULL;
++
++	node = ar->dev->of_node;
++	if (!node)
++		return -ENOENT;
++
++	of_property_read_string(node, "qcom,ath10k-calibration-variant",
++				&variant);
++	if (!variant)
++		return -ENODATA;
++
++	if (strscpy(ar->id.bdf_ext, variant, sizeof(ar->id.bdf_ext)) < 0)
++		ath10k_dbg(ar, ATH10K_DBG_BOOT,
++			   "bdf variant string is longer than the buffer can accommodate (variant: %s)\n",
++			    variant);
++
++	return 0;
++}
++
+ static int ath10k_download_and_run_otp(struct ath10k *ar)
+ {
+ 	u32 result, address = ar->hw_params.patch_load_addr;
+@@ -1522,19 +1544,19 @@ static int ath10k_core_create_board_name
+ 	/* strlen(',variant=') + strlen(ar->id.bdf_ext) */
+ 	char variant[9 + ATH10K_SMBIOS_BDF_EXT_STR_LENGTH] = { 0 };
+ 
++	if (ar->id.bdf_ext[0] != '\0')
++		scnprintf(variant, sizeof(variant), ",variant=%s",
++			  ar->id.bdf_ext);
++
+ 	if (ar->id.bmi_ids_valid) {
+ 		scnprintf(name, name_len,
+-			  "bus=%s,bmi-chip-id=%d,bmi-board-id=%d",
++			  "bus=%s,bmi-chip-id=%d,bmi-board-id=%d%s",
+ 			  ath10k_bus_str(ar->hif.bus),
+ 			  ar->id.bmi_chip_id,
+-			  ar->id.bmi_board_id);
++			  ar->id.bmi_board_id, variant);
+ 		goto out;
+ 	}
+ 
+-	if (ar->id.bdf_ext[0] != '\0')
+-		scnprintf(variant, sizeof(variant), ",variant=%s",
+-			  ar->id.bdf_ext);
+-
+ 	scnprintf(name, name_len,
+ 		  "bus=%s,vendor=%04x,device=%04x,subsystem-vendor=%04x,subsystem-device=%04x%s",
+ 		  ath10k_bus_str(ar->hif.bus),
+@@ -2964,7 +2986,11 @@ static int ath10k_core_probe_fw(struct a
+ 
+ 	ret = ath10k_core_check_smbios(ar);
+ 	if (ret)
+-		ath10k_dbg(ar, ATH10K_DBG_BOOT, "bdf variant name not set.\n");
++		ath10k_dbg(ar, ATH10K_DBG_BOOT, "SMBIOS bdf variant name not set.\n");
++
++	ret = ath10k_core_check_dt(ar);
++	if (ret)
++		ath10k_dbg(ar, ATH10K_DBG_BOOT, "DT bdf variant name not set.\n");
+ 
+ 	ret = ath10k_core_fetch_board_file(ar);
+ 	if (ret) {
diff --git a/package/kernel/ath10k-ct/patches/160-ath10k-search-all-IEs-for-variant-before-falling-back.patch b/package/kernel/ath10k-ct/patches/160-ath10k-search-all-IEs-for-variant-before-falling-back.patch
new file mode 100644
index 0000000000..a82bbda3cc
--- /dev/null
+++ b/package/kernel/ath10k-ct/patches/160-ath10k-search-all-IEs-for-variant-before-falling-back.patch
@@ -0,0 +1,249 @@
+From: Thomas Hebb <tommyhebb@gmail.com>
+Date: Fri, 13 Apr 2018 17:40:26 +0300
+Subject: [PATCH] ath10k: search all IEs for variant before falling back
+
+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>
+Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
+
+Origin: backport, https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c8489668065a283d3027e86e877b103a87f99d22
+---
+ ath10k-4.13/core.c | 134 ++++++++++++++++++---------------
+ 1 file changed, 72 insertions(+), 62 deletions(-)
+
+--- a/ath10k-4.13/core.c
++++ b/ath10k-4.13/core.c
+@@ -1419,14 +1419,61 @@ 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,
+@@ -1464,73 +1511,28 @@ 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;
+-		}
+-
+-		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 (ret == -ENOENT)
+-				/* no match found, continue */
+-				break;
+-			else if (ret)
+-				/* there was an error, bail out */
+-				goto err;
+-
+-			/* board data found */
+-			goto out;
+-		}
++	/* attempt to find boardname in the IE list */
++	ret = ath10k_core_search_bd(ar, boardname, data, len);
+ 
+-		/* jump over the padding */
+-		ie_len = ALIGN(ie_len, 4);
+-
+-		len -= ie_len;
+-		data += ie_len;
+-	}
++	/* 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);
+ 
+ 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;
+ 	}
+ 
+ 	/* Save firmware board name so we can display it later. */
+ 	strlcpy(ar->normal_mode_fw.fw_file.fw_board_name, filename,
+ 		sizeof(ar->normal_mode_fw.fw_file.fw_board_name));
+ 
++	if (ret)
++		goto err;
++
+ 	return 0;
+ 
+ err:
+@@ -1539,12 +1541,12 @@ 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);
+ 
+@@ -1570,21 +1572,31 @@ 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;
+ 	if (ar->fwcfg.bname[0])
+ 		ret = ath10k_core_fetch_board_data_api_n(ar, boardname,
++							 fallback_boardname,
+ 							 ar->fwcfg.bname);
+ 	else
+ 		ret = ath10k_core_fetch_board_data_api_n(ar, boardname,
++							 fallback_boardname,
+ 							 ATH10K_BOARD_API2_FILE);
+ 	if (!ret)
+ 		goto success;