@@ -176,3 +176,14 @@ 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---
+ This option incorporates the ADC register output as a source of
+ randomness into Linux entropy pool (/dev/urandom and /dev/random)
+
+ Say Y, feeds the entropy directly from the WiFi driver to the input
+ pool.
@@ -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
@@ -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"
@@ -1039,6 +1040,11 @@ struct ath_softc {
u32 wow_intr_before_sleep;
bool force_wow;
#endif
+
+#ifdef CONFIG_ATH9K_HWRNG
+ u32 rng_last;
+ struct task_struct *rng_task;
+#endif
};
/********/
@@ -1061,6 +1067,22 @@ static inline int ath9k_tx99_send(struct ath_softc *sc, } #endif /* CONFIG_ATH9K_TX99 */
+/***************************/
+/* Random Number Generator */
+/***************************/
+#ifdef CONFIG_ATH9K_HWRNG
+void ath9k_rng_start(struct ath_softc *sc); void ath9k_rng_stop(struct
+ath_softc *sc); #else static inline void ath9k_rng_start(struct
+ath_softc *sc) { }
+
+static inline void ath9k_rng_stop(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
@@ -739,6 +739,8 @@ static int ath9k_start(struct ieee80211_hw *hw)
ath9k_ps_restore(sc);
+ ath9k_rng_start(sc);
+
return 0;
}
@@ -828,6 +830,8 @@ static void ath9k_stop(struct ieee80211_hw *hw)
ath9k_deinit_channel_context(sc);
+ ath9k_rng_stop(sc);
+
mutex_lock(&sc->mutex);
ath_cancel_work(sc);
new file mode 100644
@@ -0,0 +1,106 @@
+/*
+ * 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 <linux/hw_random.h>
+#include <linux/kthread.h>
+
+#include "ath9k.h"
+#include "hw.h"
+#include "ar9003_phy.h"
+
+#define ATH9K_RNG_BUF_SIZE 320
+#define ATH9K_RNG_ENTROPY(x) (((x) * 8 * 320) >> 10) /* quality: 320/1024 */
+
+static int ath9k_rng_data_read(struct ath_softc *sc, u32 *buf, u32
+buf_size) {
+ int i, j;
+ u32 v1, v2, rng_last = sc->rng_last;
+ struct ath_hw *ah = sc->sc_ah;
+
+ ath9k_ps_wakeup(sc);
+
+ REG_RMW_FIELD(ah, AR_PHY_TEST, AR_PHY_TEST_BBB_OBS_SEL, 1);
+ 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);
+
+ for (i = 0, j = 0; i < buf_size; i++) {
+ v1 = REG_READ(ah, AR_PHY_TST_ADC) & 0xffff;
+ v2 = REG_READ(ah, AR_PHY_TST_ADC) & 0xffff;
+
+ /* wait for data ready */
+ if (v1 && v2 && rng_last != v1 && v1 != v2 && v1 != 0xffff &&
+ v2 != 0xffff)
+ buf[j++] = (v1 << 16) | v2;
+
+ rng_last = v2;
+ }
+
+ ath9k_ps_restore(sc);
+
+ sc->rng_last = rng_last;
+
+ return j << 2;
+}
+
+static int ath9k_rng_kthread(void *data) {
+ int bytes_read;
+ struct ath_softc *sc = data;
+ u32 *rng_buf;
+
+ rng_buf = kmalloc_array(ATH9K_RNG_BUF_SIZE, sizeof(u32), GFP_KERNEL);
+ if (!rng_buf)
+ goto out;
+
+ while (!kthread_should_stop()) {
+ bytes_read = ath9k_rng_data_read(sc, rng_buf,
+ ATH9K_RNG_BUF_SIZE);
+ if (!bytes_read) {
+ msleep_interruptible(10);
+ continue;
+ }
+
+ add_hwgenerator_randomness((void *)rng_buf, bytes_read,
+ ATH9K_RNG_ENTROPY(bytes_read));
+ }
+
+ kfree(rng_buf);
+out:
+ sc->rng_task = NULL;
+
+ return 0;
+}
+
+void ath9k_rng_start(struct ath_softc *sc) {
+ struct ath_hw *ah = sc->sc_ah;
+
+ if (sc->rng_task)
+ return;
+
+ if (!AR_SREV_9300_20_OR_LATER(ah))
+ return;
+
+ sc->rng_task = kthread_run(ath9k_rng_kthread, sc, "ath9k-hwrng");
+ if (IS_ERR(sc->rng_task))
+ sc->rng_task = NULL;
+}