From: Miaoqing Pan <miaoqing@xxxxxxxxxxxxxxxx>
We measured the FFT-based entropy in 3 ways, Shannon entropy,
collision entropy, and directly measured min-entropy. Just to
be conservative, we recommend the estimated min-Entropy to be
10 bits per 16-bit value.
Analysis was done by Jacobson,David(djacobso@xxxxxxxxxxxxxxxx).
Signed-off-by: Miaoqing Pan <miaoqing@xxxxxxxxxxxxxxxx>
---
drivers/net/wireless/ath/ath9k/Kconfig | 7 +++
drivers/net/wireless/ath/ath9k/Makefile | 1 +
drivers/net/wireless/ath/ath9k/ath9k.h | 23 ++++++++++
drivers/net/wireless/ath/ath9k/main.c | 4 ++
drivers/net/wireless/ath/ath9k/rng.c | 75 +++++++++++++++++++++++++++++++++
5 files changed, 110 insertions(+)
create mode 100644 drivers/net/wireless/ath/ath9k/rng.c
diff --git a/drivers/net/wireless/ath/ath9k/Kconfig b/drivers/net/wireless/ath/ath9k/Kconfig
index fee0cad..bde62ec9 100644
--- a/drivers/net/wireless/ath/ath9k/Kconfig
+++ b/drivers/net/wireless/ath/ath9k/Kconfig
@@ -176,3 +176,10 @@ config ATH9K_HTC_DEBUGFS
depends on ATH9K_HTC && DEBUG_FS
---help---
Say Y, if you need access to ath9k_htc's statistics.
+
+config ATH9K_HWRNG
+ bool "Random number generator support"
+ depends on ATH9K && (HW_RANDOM = y || HW_RANDOM = ATH9K)
+ default y
+ ---help---
+ Provides a hardware random number generator to the kernel.
diff --git a/drivers/net/wireless/ath/ath9k/Makefile b/drivers/net/wireless/ath/ath9k/Makefile
index ecda613..76f9dc3 100644
--- a/drivers/net/wireless/ath/ath9k/Makefile
+++ b/drivers/net/wireless/ath/ath9k/Makefile
@@ -15,6 +15,7 @@ ath9k-$(CONFIG_ATH9K_DFS_DEBUGFS) += dfs_debug.o
ath9k-$(CONFIG_ATH9K_DFS_CERTIFIED) += dfs.o
ath9k-$(CONFIG_ATH9K_TX99) += tx99.o
ath9k-$(CONFIG_ATH9K_WOW) += wow.o
+ath9k-$(CONFIG_ATH9K_HWRNG) += rng.o
ath9k-$(CONFIG_ATH9K_DEBUGFS) += debug.o
diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index a7a81b3..45596e5 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -23,6 +23,7 @@
#include <linux/leds.h>
#include <linux/completion.h>
#include <linux/time.h>
+#include <linux/hw_random.h>
#include "common.h"
#include "debug.h"
@@ -1041,6 +1042,12 @@ struct ath_softc {
u32 wow_intr_before_sleep;
bool force_wow;
#endif
+
+#ifdef CONFIG_ATH9K_HWRNG
+ struct hwrng rng;
+ bool rng_initialized;
+ u32 rng_last;
+#endif
};
/********/
@@ -1063,6 +1070,22 @@ static inline int ath9k_tx99_send(struct ath_softc *sc,
}
#endif /* CONFIG_ATH9K_TX99 */
+/***************************/
+/* Random Number Generator */
+/***************************/
+#ifdef CONFIG_ATH9K_HWRNG
+void ath9k_rng_register(struct ath_softc *sc);
+void ath9k_rng_unregister(struct ath_softc *sc);
+#else
+static inline void ath9k_rng_register(struct ath_softc *sc)
+{
+}
+
+static inline void ath9k_rng_unregister(struct ath_softc *sc)
+{
+}
+#endif
+
static inline void ath_read_cachesize(struct ath_common *common, int *csz)
{
common->bus_ops->read_cachesize(common, csz);
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index cfd45cb..5916ab2 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -739,6 +739,8 @@ static int ath9k_start(struct ieee80211_hw *hw)
ath9k_ps_restore(sc);
+ ath9k_rng_register(sc);
+
return 0;
}
@@ -828,6 +830,8 @@ static void ath9k_stop(struct ieee80211_hw *hw)
ath9k_deinit_channel_context(sc);
+ ath9k_rng_unregister(sc);
+
mutex_lock(&sc->mutex);
ath_cancel_work(sc);
diff --git a/drivers/net/wireless/ath/ath9k/rng.c b/drivers/net/wireless/ath/ath9k/rng.c
new file mode 100644
index 0000000..d8fa7a5
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/rng.c
@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2015 Qualcomm Atheros, Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "ath9k.h"
+#include "hw.h"
+#include "ar9003_phy.h"
+
+static int ath9k_rng_data_read(struct hwrng *rng, u32 *data)
+{
+ u32 v1, v2;
+ struct ath_softc *sc = (struct ath_softc *)rng->priv;
+ struct ath_hw *ah = sc->sc_ah;
+
+ ath9k_ps_wakeup(sc);
+
+ REG_RMW_FIELD(ah, AR_PHY_TEST, AR_PHY_TEST_BBB_OBS_SEL, 5);
+ REG_CLR_BIT(ah, AR_PHY_TEST, AR_PHY_TEST_RX_OBS_SEL_BIT5);
+ REG_RMW_FIELD(ah, AR_PHY_TEST_CTL_STATUS, AR_PHY_TEST_CTL_RX_OBS_SEL, 0);
+
+ v1 = REG_READ(ah, AR_PHY_TST_ADC);
+ v2 = REG_READ(ah, AR_PHY_TST_ADC);
+
+ ath9k_ps_restore(sc);
+
+ /* wait for data ready */
+ if (v1 && v2 && sc->rng_last != v1 && v1 != v2) {
+ *data = (v1 & 0xffff) | (v2 << 16);
+ sc->rng_last = v2;
+
+ return sizeof(u32);
+ }
+
+ sc->rng_last = v2;
+
+ return 0;
+}
+
+void ath9k_rng_register(struct ath_softc *sc)
+{
+ struct ath_hw *ah = sc->sc_ah;
+
+ if (WARN_ON(sc->rng_initialized))
+ return;
+
+ if (!AR_SREV_9300_20_OR_LATER(ah))
+ return;
+
+ sc->rng.name = "ath9k";
+ sc->rng.data_read = ath9k_rng_data_read;
+ sc->rng.priv = (unsigned long)sc;
+
+ if (!hwrng_register(&sc->rng))
+ sc->rng_initialized = true;
+}
+
+void ath9k_rng_unregister(struct ath_softc *sc)
+{
+ if (sc->rng_initialized) {
+ hwrng_unregister(&sc->rng);
+ sc->rng_initialized = false;
+ }
+}
--
1.9.1
--
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