wifi: mac80211: Add support for WBRF features

To support the WBRF mechanism, Wifi adapters utilized in the system must
register the frequencies in use (or unregister those frequencies no longer
used) via the dedicated calls. So that, other drivers responding to the
frequencies can take proper actions to mitigate possible interference.

Co-developed-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Co-developed-by: Evan Quan <quanliangl@hotmail.com>
Signed-off-by: Evan Quan <quanliangl@hotmail.com>
Signed-off-by: Ma Jun <Jun.Ma2@amd.com>
Link: https://msgid.link/20231211100630.2170152-5-Jun.Ma2@amd.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 95 insertions, 0 deletions

diff --git a/net/mac80211/wbrf.c b/net/mac80211/wbrf.c
new file mode 100644
index 000000000000..a05c5b971789
--- /dev/null
+++ b/net/mac80211/wbrf.c
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Wifi Band Exclusion Interface for WLAN
+ * Copyright (C) 2023 Advanced Micro Devices
+ *
+ */
+
+#include <linux/acpi_amd_wbrf.h>
+#include <linux/units.h>
+#include <net/cfg80211.h>
+#include "ieee80211_i.h"
+
+void ieee80211_check_wbrf_support(struct ieee80211_local *local)
+{
+	struct wiphy *wiphy = local->hw.wiphy;
+	struct device *dev;
+
+	if (!wiphy)
+		return;
+
+	dev = wiphy->dev.parent;
+	if (!dev)
+		return;
+
+	local->wbrf_supported = acpi_amd_wbrf_supported_producer(dev);
+	dev_dbg(dev, "WBRF is %s supported\n",
+		local->wbrf_supported ? "" : "not");
+}
+
+static void get_chan_freq_boundary(u32 center_freq, u32 bandwidth, u64 *start, u64 *end)
+{
+	bandwidth *= KHZ_PER_MHZ;
+	center_freq *= KHZ_PER_MHZ;
+
+	*start = center_freq - bandwidth / 2;
+	*end = center_freq + bandwidth / 2;
+
+	/* Frequency in Hz is expected */
+	*start = *start * HZ_PER_KHZ;
+	*end = *end * HZ_PER_KHZ;
+}
+
+static void get_ranges_from_chandef(struct cfg80211_chan_def *chandef,
+				    struct wbrf_ranges_in_out *ranges_in)
+{
+	u64 start_freq1, end_freq1;
+	u64 start_freq2, end_freq2;
+	int bandwidth;
+
+	bandwidth = nl80211_chan_width_to_mhz(chandef->width);
+
+	get_chan_freq_boundary(chandef->center_freq1, bandwidth, &start_freq1, &end_freq1);
+
+	ranges_in->band_list[0].start = start_freq1;
+	ranges_in->band_list[0].end = end_freq1;
+	ranges_in->num_of_ranges = 1;
+
+	if (chandef->width == NL80211_CHAN_WIDTH_80P80) {
+		get_chan_freq_boundary(chandef->center_freq2, bandwidth, &start_freq2, &end_freq2);
+
+		ranges_in->band_list[1].start = start_freq2;
+		ranges_in->band_list[1].end = end_freq2;
+		ranges_in->num_of_ranges++;
+	}
+}
+
+void ieee80211_add_wbrf(struct ieee80211_local *local, struct cfg80211_chan_def *chandef)
+{
+	struct wbrf_ranges_in_out ranges_in = {0};
+	struct device *dev;
+
+	if (!local->wbrf_supported)
+		return;
+
+	dev = local->hw.wiphy->dev.parent;
+
+	get_ranges_from_chandef(chandef, &ranges_in);
+
+	acpi_amd_wbrf_add_remove(dev, WBRF_RECORD_ADD, &ranges_in);
+}
+
+void ieee80211_remove_wbrf(struct ieee80211_local *local, struct cfg80211_chan_def *chandef)
+{
+	struct wbrf_ranges_in_out ranges_in = {0};
+	struct device *dev;
+
+	if (!local->wbrf_supported)
+		return;
+
+	dev = local->hw.wiphy->dev.parent;
+
+	get_ranges_from_chandef(chandef, &ranges_in);
+
+	acpi_amd_wbrf_add_remove(dev, WBRF_RECORD_REMOVE, &ranges_in);
+}