diff --git a/drivers/net/wireless/ath/ath9k/Kconfig b/drivers/net/wireless/ath/ath9k/Kconfig index fee0cadb0f5ed592fba313f1040b2e1f5ed1ebde..40fa915d6f3571ec7c00c9395b0ac223adcf09ea 100644 --- a/drivers/net/wireless/ath/ath9k/Kconfig +++ b/drivers/net/wireless/ath/ath9k/Kconfig @@ -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. diff --git a/drivers/net/wireless/ath/ath9k/Makefile b/drivers/net/wireless/ath/ath9k/Makefile index ecda613c2d547d4278ac0665c8c0eeaaf594c66a..76f9dc37500b18f70e4de8516b3ecb98ef24b511 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 acc21f60f36b7695ca5c025d879e15082c2fe54d..5294595da5a7eb45a63e14a0bbceeae1b2ef343a 100644 --- a/drivers/net/wireless/ath/ath9k/ath9k.h +++ b/drivers/net/wireless/ath/ath9k/ath9k.h @@ -23,6 +23,7 @@ #include #include #include +#include #include "common.h" #include "debug.h" @@ -1041,6 +1042,11 @@ 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 }; /********/ @@ -1063,6 +1069,22 @@ 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 index d184e682e63642955960fbcfc8602dda4ac1997c..c1b33fdcca0875a20cd2be3b54b21e46c37b725c 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_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); diff --git a/drivers/net/wireless/ath/ath9k/rng.c b/drivers/net/wireless/ath/ath9k/rng.c new file mode 100644 index 0000000000000000000000000000000000000000..c9cb2aad7b6f7ea95a87bc385b9e49c0eb9615f1 --- /dev/null +++ b/drivers/net/wireless/ath/ath9k/rng.c @@ -0,0 +1,107 @@ +/* + * 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 +#include + +#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 (unlikely(!bytes_read)) { + msleep_interruptible(10); + continue; + } + + /* sleep until entropy bits under write_wakeup_threshold */ + 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; +} + +void ath9k_rng_stop(struct ath_softc *sc) +{ + if (sc->rng_task) + kthread_stop(sc->rng_task); +}