mac80211: ath11k: Remove regulatory intersection

Currently, during initialization ath11k will receive a regulatory event
from the firmware in which it will receive the default regulatory domain
code and accompanying rules list and report those to the kernel.

Then if you try to change the regulatory domain to a different country code
it will do a weird thing in which it will send that to the FW and after
receiving the appropriate regulatory event it will parse the rules.
However, while its parsing there is a weird thing being done, and that is
that new raw rules from FW get intersected with the rules from the default
domain.
This is creating a big issue as the default domain is almost always set to
"US" or just "00" aka world so ath11k will unfairly limit you to the most
restrictive combination of rules based on the default domain and your
desired domain.
For example, in ETSI countries this is causing channels 12 and 13 on 2.4GHz
to not be usable since "US" limits 2.4GHz to 2472MHz instead of 2482MHz
like ETSI countries do.

So, lets do what TIP and even QCA do in their ath11k downstream tree and
completely get rid of the interesection code in ath11k.

Signed-off-by: Robert Marko <[email protected]>

package/kernel/mac80211/patches/ath11k/905-ath11k-remove-intersection-support-for-regulatory-ru.patch

@@ -0,0 +1,317 @@
+From abdd0985a36189ef2cc0e393b027276e86137ace Mon Sep 17 00:00:00 2001
+From: Aditya Kumar Singh <[email protected]>
+Date: Tue, 11 Apr 2023 20:08:49 +0200
+Subject: [PATCH] ath11k: remove intersection support for regulatory rules
+
+Currently, regulatory rules from new country settings is intersected with
+rules from default country settings(during initialisation) in order to prevent
+users to bypass their default country settings such as power limits, channel
+flags, etc.
+
+However, the country setting in the BDF will take higher higher precendence
+and FW will protect it. Therefore, there is no need to handle intersection
+on the driver side now.
+
+Remove regulatory rules intersection logic support.
+
+Signed-off-by: Aditya Kumar Singh <[email protected]>
+---
+ drivers/net/wireless/ath/ath11k/reg.c | 168 +++-----------------------
+ drivers/net/wireless/ath/ath11k/reg.h |   2 +-
+ drivers/net/wireless/ath/ath11k/wmi.c |  24 +---
+ 3 files changed, 16 insertions(+), 178 deletions(-)
+
+--- a/drivers/net/wireless/ath/ath11k/reg.c
++++ b/drivers/net/wireless/ath/ath11k/reg.c
+@@ -352,129 +352,6 @@ static u32 ath11k_map_fw_reg_flags(u16 r
+ 	return flags;
+ }
+ 
+-static bool
+-ath11k_reg_can_intersect(struct ieee80211_reg_rule *rule1,
+-			 struct ieee80211_reg_rule *rule2)
+-{
+-	u32 start_freq1, end_freq1;
+-	u32 start_freq2, end_freq2;
+-
+-	start_freq1 = rule1->freq_range.start_freq_khz;
+-	start_freq2 = rule2->freq_range.start_freq_khz;
+-
+-	end_freq1 = rule1->freq_range.end_freq_khz;
+-	end_freq2 = rule2->freq_range.end_freq_khz;
+-
+-	if ((start_freq1 >= start_freq2 &&
+-	     start_freq1 < end_freq2) ||
+-	    (start_freq2 > start_freq1 &&
+-	     start_freq2 < end_freq1))
+-		return true;
+-
+-	/* TODO: Should we restrict intersection feasibility
+-	 *  based on min bandwidth of the intersected region also,
+-	 *  say the intersected rule should have a  min bandwidth
+-	 * of 20MHz?
+-	 */
+-
+-	return false;
+-}
+-
+-static void ath11k_reg_intersect_rules(struct ieee80211_reg_rule *rule1,
+-				       struct ieee80211_reg_rule *rule2,
+-				       struct ieee80211_reg_rule *new_rule)
+-{
+-	u32 start_freq1, end_freq1;
+-	u32 start_freq2, end_freq2;
+-	u32 freq_diff, max_bw;
+-
+-	start_freq1 = rule1->freq_range.start_freq_khz;
+-	start_freq2 = rule2->freq_range.start_freq_khz;
+-
+-	end_freq1 = rule1->freq_range.end_freq_khz;
+-	end_freq2 = rule2->freq_range.end_freq_khz;
+-
+-	new_rule->freq_range.start_freq_khz = max_t(u32, start_freq1,
+-						    start_freq2);
+-	new_rule->freq_range.end_freq_khz = min_t(u32, end_freq1, end_freq2);
+-
+-	freq_diff = new_rule->freq_range.end_freq_khz -
+-			new_rule->freq_range.start_freq_khz;
+-	max_bw = min_t(u32, rule1->freq_range.max_bandwidth_khz,
+-		       rule2->freq_range.max_bandwidth_khz);
+-	new_rule->freq_range.max_bandwidth_khz = min_t(u32, max_bw, freq_diff);
+-
+-	new_rule->power_rule.max_antenna_gain =
+-		min_t(u32, rule1->power_rule.max_antenna_gain,
+-		      rule2->power_rule.max_antenna_gain);
+-
+-	new_rule->power_rule.max_eirp = min_t(u32, rule1->power_rule.max_eirp,
+-					      rule2->power_rule.max_eirp);
+-
+-	/* Use the flags of both the rules */
+-	new_rule->flags = rule1->flags | rule2->flags;
+-
+-	/* To be safe, lts use the max cac timeout of both rules */
+-	new_rule->dfs_cac_ms = max_t(u32, rule1->dfs_cac_ms,
+-				     rule2->dfs_cac_ms);
+-}
+-
+-static struct ieee80211_regdomain *
+-ath11k_regd_intersect(struct ieee80211_regdomain *default_regd,
+-		      struct ieee80211_regdomain *curr_regd)
+-{
+-	u8 num_old_regd_rules, num_curr_regd_rules, num_new_regd_rules;
+-	struct ieee80211_reg_rule *old_rule, *curr_rule, *new_rule;
+-	struct ieee80211_regdomain *new_regd = NULL;
+-	u8 i, j, k;
+-
+-	num_old_regd_rules = default_regd->n_reg_rules;
+-	num_curr_regd_rules = curr_regd->n_reg_rules;
+-	num_new_regd_rules = 0;
+-
+-	/* Find the number of intersecting rules to allocate new regd memory */
+-	for (i = 0; i < num_old_regd_rules; i++) {
+-		old_rule = default_regd->reg_rules + i;
+-		for (j = 0; j < num_curr_regd_rules; j++) {
+-			curr_rule = curr_regd->reg_rules + j;
+-
+-			if (ath11k_reg_can_intersect(old_rule, curr_rule))
+-				num_new_regd_rules++;
+-		}
+-	}
+-
+-	if (!num_new_regd_rules)
+-		return NULL;
+-
+-	new_regd = kzalloc(sizeof(*new_regd) + (num_new_regd_rules *
+-			sizeof(struct ieee80211_reg_rule)),
+-			GFP_ATOMIC);
+-
+-	if (!new_regd)
+-		return NULL;
+-
+-	/* We set the new country and dfs region directly and only trim
+-	 * the freq, power, antenna gain by intersecting with the
+-	 * default regdomain. Also MAX of the dfs cac timeout is selected.
+-	 */
+-	new_regd->n_reg_rules = num_new_regd_rules;
+-	memcpy(new_regd->alpha2, curr_regd->alpha2, sizeof(new_regd->alpha2));
+-	new_regd->dfs_region = curr_regd->dfs_region;
+-	new_rule = new_regd->reg_rules;
+-
+-	for (i = 0, k = 0; i < num_old_regd_rules; i++) {
+-		old_rule = default_regd->reg_rules + i;
+-		for (j = 0; j < num_curr_regd_rules; j++) {
+-			curr_rule = curr_regd->reg_rules + j;
+-
+-			if (ath11k_reg_can_intersect(old_rule, curr_rule))
+-				ath11k_reg_intersect_rules(old_rule, curr_rule,
+-							   (new_rule + k++));
+-		}
+-	}
+-	return new_regd;
+-}
+-
+ static const char *
+ ath11k_reg_get_regdom_str(enum nl80211_dfs_regions dfs_region)
+ {
+@@ -609,9 +486,9 @@ ath11k_reg_update_weather_radar_band(str
+ 
+ struct ieee80211_regdomain *
+ ath11k_reg_build_regd(struct ath11k_base *ab,
+-		      struct cur_regulatory_info *reg_info, bool intersect)
++		      struct cur_regulatory_info *reg_info)
+ {
+-	struct ieee80211_regdomain *tmp_regd, *default_regd, *new_regd = NULL;
++	struct ieee80211_regdomain *new_regd = NULL;
+ 	struct cur_reg_rule *reg_rule;
+ 	u8 i = 0, j = 0, k = 0;
+ 	u8 num_rules;
+@@ -628,26 +505,26 @@ ath11k_reg_build_regd(struct ath11k_base
+ 		num_rules += reg_info->num_6ghz_rules_ap[WMI_REG_INDOOR_AP];
+ 
+ 	if (!num_rules)
+-		goto ret;
++		return new_regd;
+ 
+ 	/* Add max additional rules to accommodate weather radar band */
+ 	if (reg_info->dfs_region == ATH11K_DFS_REG_ETSI)
+ 		num_rules += 2;
+ 
+-	tmp_regd =  kzalloc(sizeof(*tmp_regd) +
++	new_regd =  kzalloc(sizeof(*new_regd) +
+ 			(num_rules * sizeof(struct ieee80211_reg_rule)),
+ 			GFP_ATOMIC);
+-	if (!tmp_regd)
+-		goto ret;
++	if (!new_regd)
++		return new_regd;
+ 
+-	memcpy(tmp_regd->alpha2, reg_info->alpha2, REG_ALPHA2_LEN + 1);
++	memcpy(new_regd->alpha2, reg_info->alpha2, REG_ALPHA2_LEN + 1);
+ 	memcpy(alpha2, reg_info->alpha2, REG_ALPHA2_LEN + 1);
+ 	alpha2[2] = '\0';
+-	tmp_regd->dfs_region = ath11k_map_fw_dfs_region(reg_info->dfs_region);
++	new_regd->dfs_region = ath11k_map_fw_dfs_region(reg_info->dfs_region);
+ 
+ 	ath11k_dbg(ab, ATH11K_DBG_REG,
+ 		   "Country %s, CFG Regdomain %s FW Regdomain %d, num_reg_rules %d\n",
+-		   alpha2, ath11k_reg_get_regdom_str(tmp_regd->dfs_region),
++		   alpha2, ath11k_reg_get_regdom_str(new_regd->dfs_region),
+ 		   reg_info->dfs_region, num_rules);
+ 	/* Update reg_rules[] below. Firmware is expected to
+ 	 * send these rules in order(2 GHz rules first and then 5 GHz)
+@@ -686,7 +563,7 @@ ath11k_reg_build_regd(struct ath11k_base
+ 
+ 		flags |= ath11k_map_fw_reg_flags(reg_rule->flags);
+ 
+-		ath11k_reg_update_rule(tmp_regd->reg_rules + i,
++		ath11k_reg_update_rule(new_regd->reg_rules + i,
+ 				       reg_rule->start_freq,
+ 				       reg_rule->end_freq, max_bw,
+ 				       reg_rule->ant_gain, reg_rule->reg_power,
+@@ -701,7 +578,7 @@ ath11k_reg_build_regd(struct ath11k_base
+ 		    reg_info->dfs_region == ATH11K_DFS_REG_ETSI &&
+ 		    (reg_rule->end_freq > ETSI_WEATHER_RADAR_BAND_LOW &&
+ 		    reg_rule->start_freq < ETSI_WEATHER_RADAR_BAND_HIGH)){
+-			ath11k_reg_update_weather_radar_band(ab, tmp_regd,
++			ath11k_reg_update_weather_radar_band(ab, new_regd,
+ 							     reg_rule, &i,
+ 							     flags, max_bw);
+ 			continue;
+@@ -712,37 +589,20 @@ ath11k_reg_build_regd(struct ath11k_base
+ 				   "\t%d. (%d - %d @ %d) (%d, %d) (%d ms) (FLAGS %d) (%d, %d)\n",
+ 				   i + 1, reg_rule->start_freq, reg_rule->end_freq,
+ 				   max_bw, reg_rule->ant_gain, reg_rule->reg_power,
+-				   tmp_regd->reg_rules[i].dfs_cac_ms, flags,
++				   new_regd->reg_rules[i].dfs_cac_ms, flags,
+ 				   reg_rule->psd_flag, reg_rule->psd_eirp);
+ 		} else {
+ 			ath11k_dbg(ab, ATH11K_DBG_REG,
+ 				   "\t%d. (%d - %d @ %d) (%d, %d) (%d ms) (FLAGS %d)\n",
+ 				   i + 1, reg_rule->start_freq, reg_rule->end_freq,
+ 				   max_bw, reg_rule->ant_gain, reg_rule->reg_power,
+-				   tmp_regd->reg_rules[i].dfs_cac_ms,
++				   new_regd->reg_rules[i].dfs_cac_ms,
+ 				   flags);
+ 		}
+ 	}
+ 
+-	tmp_regd->n_reg_rules = i;
+-
+-	if (intersect) {
+-		default_regd = ab->default_regd[reg_info->phy_id];
+-
+-		/* Get a new regd by intersecting the received regd with
+-		 * our default regd.
+-		 */
+-		new_regd = ath11k_regd_intersect(default_regd, tmp_regd);
+-		kfree(tmp_regd);
+-		if (!new_regd) {
+-			ath11k_warn(ab, "Unable to create intersected regdomain\n");
+-			goto ret;
+-		}
+-	} else {
+-		new_regd = tmp_regd;
+-	}
++	new_regd->n_reg_rules = i;
+ 
+-ret:
+ 	return new_regd;
+ }
+ 
+--- a/drivers/net/wireless/ath/ath11k/reg.h
++++ b/drivers/net/wireless/ath/ath11k/reg.h
+@@ -30,7 +30,7 @@ void ath11k_reg_free(struct ath11k_base
+ void ath11k_regd_update_work(struct work_struct *work);
+ struct ieee80211_regdomain *
+ ath11k_reg_build_regd(struct ath11k_base *ab,
+-		      struct cur_regulatory_info *reg_info, bool intersect);
++		      struct cur_regulatory_info *reg_info);
+ int ath11k_regd_update(struct ath11k *ar);
+ int ath11k_reg_update_chan_list(struct ath11k *ar, bool wait);
+ #endif
+--- a/drivers/net/wireless/ath/ath11k/wmi.c
++++ b/drivers/net/wireless/ath/ath11k/wmi.c
+@@ -6979,24 +6979,12 @@ static void ath11k_wmi_htc_tx_complete(s
+ 		wake_up(&wmi->tx_ce_desc_wq);
+ }
+ 
+-static bool ath11k_reg_is_world_alpha(char *alpha)
+-{
+-	if (alpha[0] == '0' && alpha[1] == '0')
+-		return true;
+-
+-	if (alpha[0] == 'n' && alpha[1] == 'a')
+-		return true;
+-
+-	return false;
+-}
+-
+ static int ath11k_reg_chan_list_event(struct ath11k_base *ab,
+ 				      struct sk_buff *skb,
+ 				      enum wmi_reg_chan_list_cmd_type id)
+ {
+ 	struct cur_regulatory_info *reg_info = NULL;
+ 	struct ieee80211_regdomain *regd = NULL;
+-	bool intersect = false;
+ 	int ret = 0, pdev_idx, i, j;
+ 	struct ath11k *ar;
+ 
+@@ -7058,17 +7046,7 @@ static int ath11k_reg_chan_list_event(st
+ 		    (char *)reg_info->alpha2, 2))
+ 		goto mem_free;
+ 
+-	/* Intersect new rules with default regd if a new country setting was
+-	 * requested, i.e a default regd was already set during initialization
+-	 * and the regd coming from this event has a valid country info.
+-	 */
+-	if (ab->default_regd[pdev_idx] &&
+-	    !ath11k_reg_is_world_alpha((char *)
+-		ab->default_regd[pdev_idx]->alpha2) &&
+-	    !ath11k_reg_is_world_alpha((char *)reg_info->alpha2))
+-		intersect = true;
+-
+-	regd = ath11k_reg_build_regd(ab, reg_info, intersect);
++	regd = ath11k_reg_build_regd(ab, reg_info);
+ 	if (!regd) {
+ 		ath11k_warn(ab, "failed to build regd from reg_info\n");
+ 		goto fallback;