diff mbox series

[v3,01/12] cfg80211: regulatory: extend regulatory support for S1G

Message ID 20220906044812.7609-2-kieran.frewen@morsemicro.com (mailing list archive)
State Changes Requested
Delegated to: Johannes Berg
Headers show
Series Additional Support for 802.11ah (S1G) | expand

Commit Message

Kieran Frewen Sept. 6, 2022, 4:48 a.m. UTC
Extend the S1G regulatory information to support all regulatory
domains. An reg_s1g.h file is included containing structs with key
regulatory class information. These structs were required to ensure
the right combination of information was available to a series of
functions which support the mapping between frequencies, bandwidths,
and channels.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Kieran Frewen <kieran.frewen@morsemicro.com>
---
 include/net/cfg80211.h |   8 ++
 net/wireless/Makefile  |   2 +-
 net/wireless/reg.c     |  60 +++++++++--
 net/wireless/reg_s1g.c | 231 +++++++++++++++++++++++++++++++++++++++++
 net/wireless/reg_s1g.h |  53 ++++++++++
 net/wireless/util.c    |  35 ++++++-
 6 files changed, 376 insertions(+), 13 deletions(-)
 create mode 100644 net/wireless/reg_s1g.c
 create mode 100644 net/wireless/reg_s1g.h

Comments

Johannes Berg Sept. 6, 2022, 9:36 a.m. UTC | #1
On Tue, 2022-09-06 at 16:48 +1200, Kieran Frewen wrote:
> Extend the S1G regulatory information to support all regulatory
> domains. An reg_s1g.h file is included containing structs with key
> regulatory class information. These structs were required to ensure
> the right combination of information was available to a series of
> functions which support the mapping between frequencies, bandwidths,
> and channels.
> 

Hm. Isn't this type of thing something we'd usually want to keep in the
regulatory database to be able to update it? Who says JP will always
stick to their restrictive scheme, for example.

johannes
Kieran Frewen Sept. 21, 2022, 10:10 p.m. UTC | #2
On Tue, Sep 6, 2022 at 9:36 PM Johannes Berg <johannes@sipsolutions.net> wrote:
>
> On Tue, 2022-09-06 at 16:48 +1200, Kieran Frewen wrote:
> > Extend the S1G regulatory information to support all regulatory
> > domains. An reg_s1g.h file is included containing structs with key
> > regulatory class information. These structs were required to ensure
> > the right combination of information was available to a series of
> > functions which support the mapping between frequencies, bandwidths,
> > and channels.
> >
>
> Hm. Isn't this type of thing something we'd usually want to keep in the
> regulatory database to be able to update it? Who says JP will always
> stick to their restrictive scheme, for example.
>
> johannes

Yes I agree that this information would be best stored in the
regulatory database.
Especially in respect to maintaining a single up-to-date source of knowledge.
I have done a bit of investigation into what information we would
require in order
to maintain the same level of functionality. I think at the very least
we would have to
add the base frequency to what already exists in the regulatory
database. By adding
this we would maintain the ability to map from S1G channels to frequencies. We
would, however, lose the ability to specify exact bandwidths for a
certain frequency
as is the current behaviour in reg_rule_to_chan_bw_flags() and would
likely have to
change the S1G bandwidth flags to not permit certain bandwidths on a
channel, e.g.
 IEEE80211_CHAN_NO_2MHZ as opposed to flagging a single allowed bandwidth.

I do wonder that if we do add a base frequency to the regulatory database are we
straying from just maintaining information which permits or prevents operation
in a regulatory domain for a specific frequency and starting to
include information
that the kernel is relying on for mapping from one field to another, e.g.
ieee80211_channel_to_freq_khz().

Kieran
diff mbox series

Patch

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 908d58393484..945e7700de66 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -5909,6 +5909,14 @@  ieee80211_channel_to_khz(const struct ieee80211_channel *chan)
 	return MHZ_TO_KHZ(chan->center_freq) + chan->freq_offset;
 }
 
+/**
+ * ieee80211_s1g_channel_to_freq_khz - convert S1G channel index to
+ * frequency in khz
+ * @chan: int channel index to convert
+ * Return: The corresponding frequency (in KHz)
+ */
+u32 ieee80211_s1g_channel_to_freq_khz(int chan);
+
 /**
  * ieee80211_s1g_channel_width - get allowed channel width from @chan
  *
diff --git a/net/wireless/Makefile b/net/wireless/Makefile
index 527ae669f6f7..10cc0db5a935 100644
--- a/net/wireless/Makefile
+++ b/net/wireless/Makefile
@@ -10,7 +10,7 @@  obj-$(CONFIG_WEXT_PROC) += wext-proc.o
 obj-$(CONFIG_WEXT_SPY) += wext-spy.o
 obj-$(CONFIG_WEXT_PRIV) += wext-priv.o
 
-cfg80211-y += core.o sysfs.o radiotap.o util.o reg.o scan.o nl80211.o
+cfg80211-y += core.o sysfs.o radiotap.o util.o reg.o reg_s1g.o scan.o nl80211.o
 cfg80211-y += mlme.o ibss.o sme.o chan.o ethtool.o mesh.o ap.o trace.o ocb.o
 cfg80211-y += pmsr.o
 cfg80211-$(CONFIG_OF) += of.o
diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index c7383ede794f..3377cea16c2b 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -62,6 +62,7 @@ 
 #include "reg.h"
 #include "rdev-ops.h"
 #include "nl80211.h"
+#include "reg_s1g.h"
 
 /*
  * Grace period we give before making sure all current interfaces reside on
@@ -1737,26 +1738,54 @@  static uint32_t reg_rule_to_chan_bw_flags(const struct ieee80211_regdomain *regd
 		 * the largest bandwidth which cleanly divides the freq_range.
 		 */
 		int edge_offset;
-		int ch_bw = max_bandwidth_khz;
+		int ch_bw, freq_end, freq_start, class_idx = -1;
+		unsigned int i;
+		const struct s1g_oper_class *oper = reg_s1g_get_oper_class(regd->alpha2);
+
+		if (!oper) {
+			bw_flags |= IEEE80211_CHAN_DISABLED;
+			return bw_flags;
+		}
+
+		for (i = 0; i < oper->class_count; i++) {
+			if (center_freq_khz >= oper->class[i].start_freq &&
+			    center_freq_khz <= oper->class[i].end_freq) {
+				class_idx = i;
+				break;
+			}
+		}
+
+		if (class_idx == -1) {
+			bw_flags |= IEEE80211_CHAN_DISABLED;
+			return bw_flags;
+		}
+
+		ch_bw = oper->class[class_idx].max_bw_khz;
+		freq_start = oper->class[class_idx].start_freq;
+		freq_end = oper->class[class_idx].end_freq;
 
 		while (ch_bw) {
-			edge_offset = (center_freq_khz - ch_bw / 2) -
-				      freq_range->start_freq_khz;
-			if (edge_offset % ch_bw == 0) {
-				switch (KHZ_TO_MHZ(ch_bw)) {
-				case 1:
+			if (oper->class[class_idx].align_to_end)
+				edge_offset = freq_end -
+					(center_freq_khz - (ch_bw) / 2);
+			else
+				edge_offset = (center_freq_khz - (ch_bw) / 2) -
+					freq_start;
+			if (edge_offset % (ch_bw) == 0) {
+				switch (ch_bw) {
+				case MHZ_TO_KHZ(1):
 					bw_flags |= IEEE80211_CHAN_1MHZ;
 					break;
-				case 2:
+				case MHZ_TO_KHZ(2):
 					bw_flags |= IEEE80211_CHAN_2MHZ;
 					break;
-				case 4:
+				case MHZ_TO_KHZ(4):
 					bw_flags |= IEEE80211_CHAN_4MHZ;
 					break;
-				case 8:
+				case MHZ_TO_KHZ(8):
 					bw_flags |= IEEE80211_CHAN_8MHZ;
 					break;
-				case 16:
+				case MHZ_TO_KHZ(16):
 					bw_flags |= IEEE80211_CHAN_16MHZ;
 					break;
 				default:
@@ -2555,9 +2584,18 @@  static void handle_channel_custom(struct wiphy *wiphy,
 	const struct ieee80211_reg_rule *reg_rule = NULL;
 	const struct ieee80211_power_rule *power_rule = NULL;
 	u32 bw, center_freq_khz;
+	bool is_s1g = chan->band == NL80211_BAND_S1GHZ;
 
 	center_freq_khz = ieee80211_channel_to_khz(chan);
-	for (bw = MHZ_TO_KHZ(20); bw >= min_bw; bw = bw / 2) {
+
+	if (is_s1g) {
+		bw = MHZ_TO_KHZ(16);
+		min_bw = MHZ_TO_KHZ(1);
+	} else {
+		bw = MHZ_TO_KHZ(20);
+	}
+
+	for (; bw >= min_bw; bw = bw / 2) {
 		reg_rule = freq_reg_info_regd(center_freq_khz, regd, bw);
 		if (!IS_ERR(reg_rule))
 			break;
diff --git a/net/wireless/reg_s1g.c b/net/wireless/reg_s1g.c
new file mode 100644
index 000000000000..6727d9986419
--- /dev/null
+++ b/net/wireless/reg_s1g.c
@@ -0,0 +1,231 @@ 
+// SPDX-License-Identifier: GPL-2.0
+#include "reg_s1g.h"
+
+/* The following channel lists have been retrieved from
+ * IEEE Std 802.11-2020 Table E-5
+ */
+static const u8 us_supported_channels[] = {
+	1, 2, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13,
+	14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
+	24, 25, 26, 27, 28, 29, 30, 31, 32, 33,
+	34, 35, 37, 38, 39, 40, 41, 42, 43, 44,
+	45, 46, 47, 48, 49, 50, 51
+};
+
+static const u8 eu_supported_channels_863[] = {
+	1, 3, 5, 7, 9
+};
+
+static const u8 eu_supported_channels_901_4[] = {
+	33, 35
+};
+
+static const u8 jp_supported_channels[] = {
+	1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21
+};
+
+static const u8 kr_supported_channels[] = {
+	1, 2, 3, 5, 6, 7, 8, 9, 10, 11
+};
+
+static const u8 sg_supported_channels_863[] = {
+	7, 9, 10, 11
+};
+
+static const u8 sg_supported_channels_902[] = {
+	37, 38, 39, 40, 41, 42, 43, 45
+};
+
+static const u8 au_nz_supported_channels[] = {
+	27, 29, 30, 31, 32, 33, 34, 35, 37, 38, 39,
+	40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,
+	51
+};
+
+/* The following s1g_oper_class structs are taken from
+ * IEEE Std 802.11-2020 Table E-5
+ */
+static const struct s1g_oper_class country_class_au = {
+	.cc = "AU",
+	.class_count = 2,
+	.class = {
+	{
+		.band_start = 902000,
+		.start_freq = 915000,
+		.end_freq = 920000,
+		.max_bw_khz = MHZ_TO_KHZ(4),
+		.align_to_end = false,
+		.supported_chan = au_nz_supported_channels,
+		.n_supported_chan = sizeof(au_nz_supported_channels),
+	},
+	{
+		.band_start = 902000,
+		.start_freq = 920000,
+		.end_freq = 928000,
+		.max_bw_khz = MHZ_TO_KHZ(8),
+		.align_to_end = true,
+		.supported_chan = NULL,
+		.n_supported_chan = 0,
+	}
+	},
+};
+
+static const struct s1g_oper_class country_class_nz = {
+	.cc = "NZ",
+	.class_count = 2,
+	.class = {
+	{
+		.band_start = 902000,
+		.start_freq = 915000,
+		.end_freq = 924000,
+		.max_bw_khz = MHZ_TO_KHZ(8),
+		.align_to_end = false,
+		.supported_chan = au_nz_supported_channels,
+		.n_supported_chan = sizeof(au_nz_supported_channels),
+	},
+	{
+		.band_start = 902000,
+		.start_freq = 924000,
+		.end_freq = 928000,
+		.max_bw_khz = MHZ_TO_KHZ(8),
+		.align_to_end = false,
+		.supported_chan = NULL,
+		.n_supported_chan = 0,
+	}
+	},
+};
+
+static const struct s1g_oper_class country_class_us = {
+	.cc = "US",
+	.class_count = 3,
+	.class = {
+	{
+		.band_start = 902000,
+		.start_freq = 902000,
+		.end_freq = 904000,
+		.max_bw_khz = MHZ_TO_KHZ(16),
+		.align_to_end = false,
+		.supported_chan = us_supported_channels,
+		.n_supported_chan = sizeof(us_supported_channels),
+	},
+	{
+		.band_start = 902000,
+		.start_freq = 920000,
+		.end_freq = 928000,
+		.max_bw_khz = MHZ_TO_KHZ(16),
+		.align_to_end = false,
+		.supported_chan = NULL,
+		.n_supported_chan = 0,
+	},
+	{
+		.band_start = 902000,
+		.start_freq = 904000,
+		.end_freq = 920000,
+		.max_bw_khz = MHZ_TO_KHZ(16),
+		.align_to_end = false,
+		.supported_chan = NULL,
+		.n_supported_chan = 0,
+	}
+	},
+};
+
+static const struct s1g_oper_class country_class_sg = {
+	.cc = "SG",
+	.class_count = 2,
+	.class = {
+	{
+		.band_start = 863000,
+		.start_freq = 866000,
+		.end_freq = 869000,
+		.max_bw_khz = MHZ_TO_KHZ(2),
+		.align_to_end = true,
+		.supported_chan = sg_supported_channels_863,
+		.n_supported_chan = sizeof(sg_supported_channels_863),
+	},
+	{
+		.band_start = 902000,
+		.start_freq = 920000,
+		.end_freq = 925000,
+		.max_bw_khz = MHZ_TO_KHZ(4),
+		.align_to_end = false,
+		.supported_chan = sg_supported_channels_902,
+		.n_supported_chan = sizeof(sg_supported_channels_902),
+	},
+	},
+};
+
+static const struct s1g_oper_class country_class_kr = {
+	.cc = "KR",
+	.class_count = 1,
+	.class = {
+	{
+		.band_start = 917500,
+		.start_freq = 917500,
+		.end_freq = 923500,
+		.max_bw_khz = MHZ_TO_KHZ(4),
+		.align_to_end = true,
+		.supported_chan = kr_supported_channels,
+		.n_supported_chan = sizeof(kr_supported_channels),
+	}
+	},
+};
+
+static const struct s1g_oper_class country_class_eu = {
+	.cc = "EU",
+	.class_count = 1,
+	.class = {
+	{
+		.band_start = 863000,
+		.start_freq = 863000,
+		.end_freq = 868000,
+		.max_bw_khz = MHZ_TO_KHZ(1),
+		.align_to_end = false,
+		.supported_chan = eu_supported_channels_863,
+		.n_supported_chan = sizeof(eu_supported_channels_863),
+	},
+	{
+		.band_start = 901400,
+		.start_freq = 917400,
+		.end_freq = 919400,
+		.max_bw_khz = MHZ_TO_KHZ(1),
+		.align_to_end = false,
+		.supported_chan = eu_supported_channels_901_4,
+		.n_supported_chan = sizeof(eu_supported_channels_901_4),
+	}
+	},
+};
+
+static const struct s1g_oper_class country_class_jp = {
+	.cc = "JP",
+	.class_count = 1,
+	.class = {
+	{
+		.band_start = 916500,
+		.start_freq = 916500,
+		.end_freq = 927500,
+		.max_bw_khz = MHZ_TO_KHZ(1),
+		.align_to_end = false,
+		.supported_chan = jp_supported_channels,
+		.n_supported_chan = sizeof(jp_supported_channels),
+	}
+	},
+};
+
+const struct s1g_oper_class *reg_s1g_get_oper_class(const char *cc)
+{
+	if (!strcmp(cc, "EU"))
+		return &country_class_eu;
+	if (!strcmp(cc, "SG"))
+		return &country_class_sg;
+	if (!strcmp(cc, "US"))
+		return &country_class_us;
+	if (!strcmp(cc, "AU"))
+		return &country_class_au;
+	if (!strcmp(cc, "KR"))
+		return &country_class_kr;
+	if (!strcmp(cc, "JP"))
+		return &country_class_jp;
+	if (!strcmp(cc, "NZ"))
+		return &country_class_nz;
+	return NULL;
+}
diff --git a/net/wireless/reg_s1g.h b/net/wireless/reg_s1g.h
new file mode 100644
index 000000000000..3165166054d2
--- /dev/null
+++ b/net/wireless/reg_s1g.h
@@ -0,0 +1,53 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __NET_WIRELESS_REG_S1G_H
+#define __NET_WIRELESS_REG_S1G_H
+
+#include "reg.h"
+
+/**
+ * Struct cca_class
+ *
+ * The specifics of a cca level classification used to validate bw/frequency
+ *	combinations in a regulatory domain
+ * @band_start: The channel starting frequency (kHz) for that CCA classification
+ * @start_freq: The start of the valid frequency (kHz) range for the CCA
+ *	classification
+ * @end_freq: The end of the valid frequency (kHz) range for the CCA
+ *	classification
+ * @max_bw_khz: The maximum valid bandwidth for the CCA classification
+ * @align_to_end: True if the maximum valid bandwidth for the range is aligned
+ *	to the end_freq
+ * @supported_chan: A list of supported channel indexes
+ * @n_supported_chan: A count of the supported channels for this CCA
+ *	classification
+ */
+struct s1g_cca_classification {
+	u32 band_start;
+	u32 start_freq;
+	u32 end_freq;
+	u32 max_bw_khz;
+	bool align_to_end;
+	const u8 *supported_chan;
+	u8 n_supported_chan;
+};
+
+/**
+ * Struct s1g_oper_class
+ *
+ * An aggregated view of the operating classes for a single regulatory
+ * domain
+ * @cc: country code (2-character code)
+ * @class_count: The number of CCA level classifications that exist
+ *	within that country
+ * @class: The specifics of a CCA level classification within a regulatory
+ *	domain.
+ */
+struct s1g_oper_class {
+	char cc[3];
+	int class_count;
+	struct s1g_cca_classification class[];
+};
+
+const struct s1g_oper_class *reg_s1g_get_oper_class(const char *cc);
+
+#endif /*__NET_WIRELESS_REG_S1G_H */
diff --git a/net/wireless/util.c b/net/wireless/util.c
index 2c127951764a..aeccb6ce595c 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -22,6 +22,7 @@ 
 #include <linux/nospec.h>
 #include "core.h"
 #include "rdev-ops.h"
+#include "reg_s1g.h"
 
 
 const struct ieee80211_rate *
@@ -72,6 +73,27 @@  u32 ieee80211_mandatory_rates(struct ieee80211_supported_band *sband,
 }
 EXPORT_SYMBOL(ieee80211_mandatory_rates);
 
+static u32 ieee80211_s1g_base_freq(int chan)
+{
+	const struct ieee80211_regdomain *regd  = rtnl_dereference(cfg80211_regdomain);
+	const struct s1g_oper_class *oper = reg_s1g_get_oper_class(regd->alpha2);
+	u8 i, j, index = 0;
+
+	if (!oper)
+		return 0;
+
+	if (oper->class_count > 1)
+		for (i = 0; i < oper->class_count; i++)
+			for (j = 0; j < oper->class[i].n_supported_chan; j++)
+				if (oper->class[i].supported_chan[j] == chan) {
+					index = i;
+					goto out;
+				}
+	return 0; /* not supported */
+out:
+	return oper->class[index].band_start;
+}
+
 u32 ieee80211_channel_to_freq_khz(int chan, enum nl80211_band band)
 {
 	/* see 802.11 17.3.8.3.2 and Annex J
@@ -104,7 +126,7 @@  u32 ieee80211_channel_to_freq_khz(int chan, enum nl80211_band band)
 			return MHZ_TO_KHZ(56160 + chan * 2160);
 		break;
 	case NL80211_BAND_S1GHZ:
-		return 902000 + chan * 500;
+		return ieee80211_s1g_base_freq(chan) + chan * 500;
 	default:
 		;
 	}
@@ -112,6 +134,17 @@  u32 ieee80211_channel_to_freq_khz(int chan, enum nl80211_band band)
 }
 EXPORT_SYMBOL(ieee80211_channel_to_freq_khz);
 
+u32 ieee80211_s1g_channel_to_freq_khz(int chan)
+{
+	u32 base = ieee80211_s1g_base_freq(chan);
+
+	if (!base)
+		return 0;
+
+	return (base + chan * 500);
+}
+EXPORT_SYMBOL(ieee80211_s1g_channel_to_freq_khz);
+
 enum nl80211_chan_width
 ieee80211_s1g_channel_width(const struct ieee80211_channel *chan)
 {