Hi,
REX ABERT wrote:
> Still up and running 3.5 days without a Noise Floor Calibration Timeout.
Kernel team: please consider the following patches for squeeze:
9d332c82b4cf ath5k: initialize default noise floor
e5e2647fd6ce ath5k: use noise calibration from madwifi hal
The former is for the sake of the latter. Rex tested the pair and
found it to fix this bug:
| The only way to reconnect wireless is to shut down and power off---a
| reboot is not sufficient.
Unfortunately this is a little too big a change for the upstream
stable tree (at least by stable_kernel_rules.txt standards) but it's
well tested in ath5k and in madwifi before that.
Patch against the kernel packaging repo attached for convenience.
Hope that helps,
Jonathan
Index: debian/changelog
===================================================================
--- debian/changelog (revision 19148)
+++ debian/changelog (working copy)
@@ -7,6 +7,10 @@
* linux-image: Relax version dependency on linux-base, to simplify
testing of bug fixes
+ [ Jonathan Nieder ]
+ * ath5k: initialize default noise floor
+ * ath5k: use noise calibration from madwifi hal (Closes: #611107)
+
-- Bastian Blank <wa...@debian.org> Mon, 07 May 2012 19:18:05 +0200
linux-2.6 (2.6.32-45) stable; urgency=high
Index: debian/patches/bugfix/all/ath5k-initialize-default-noise-floor.patch
===================================================================
--- debian/patches/bugfix/all/ath5k-initialize-default-noise-floor.patch
(revision 0)
+++ debian/patches/bugfix/all/ath5k-initialize-default-noise-floor.patch
(working copy)
@@ -0,0 +1,32 @@
+From: Bruno Randolf <b...@einfach.org>
+Date: Thu, 25 Mar 2010 14:49:31 +0900
+Subject: ath5k: initialize default noise floor
+
+commit 9d332c82b4cf2e4538450e4af40f073cc5e599ec upstream.
+
+Initialize noise floor variable with a default of -95. This was used
+uninitialized in the signal strength (RSSI -> dBm) conversion until the first
+noise floor calibration was completed.
+
+Signed-off-by: Bruno Randolf <b...@einfach.org>
+Signed-off-by: John W. Linville <linvi...@tuxdriver.com>
+Signed-off-by: Jonathan Nieder <jrnie...@gmail.com>
+---
+ drivers/net/wireless/ath/ath5k/attach.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/drivers/net/wireless/ath/ath5k/attach.c
b/drivers/net/wireless/ath/ath5k/attach.c
+index 88663dfe3b3d..b5ea906cd7c8 100644
+--- a/drivers/net/wireless/ath/ath5k/attach.c
++++ b/drivers/net/wireless/ath/ath5k/attach.c
+@@ -134,6 +134,7 @@ struct ath5k_hw *ath5k_hw_attach(struct ath5k_softc *sc)
+ ah->ah_limit_tx_retries = AR5K_INIT_TX_RETRY;
+ ah->ah_software_retry = false;
+ ah->ah_current_channel = &sc->channels[0];
++ ah->ah_noise_floor = -95; /* until first NF calibration is run */
+
+ /*
+ * Find the mac version
+--
+1.7.10
+
Index:
debian/patches/bugfix/all/ath5k-use-noise-calibration-from-madwifi-hal.patch
===================================================================
---
debian/patches/bugfix/all/ath5k-use-noise-calibration-from-madwifi-hal.patch
(revision 0)
+++
debian/patches/bugfix/all/ath5k-use-noise-calibration-from-madwifi-hal.patch
(working copy)
@@ -0,0 +1,383 @@
+From: Bob Copeland <m...@bobcopeland.com>
+Date: Wed, 14 Oct 2009 14:16:30 -0400
+Subject: ath5k: use noise calibration from madwifi hal
+
+commit e5e2647fd6ceef2cdc479954b84517535eb7febd upstream.
+
+This updates ath5k to calibrate the noise floor similar to the
+way it is done in the madwifi hal and ath9k. Of note:
+
+- we start NF measurement at the same time as AGC calibration,
+ but do not actually read the value until the periodic (long)
+ calibration
+- we keep a history of the last few values read and write the
+ median back to the hardware for CCA
+- we do not complain if NF calibration isn't complete, instead
+ we keep the last read value.
+
+Signed-off-by: Bob Copeland <m...@bobcopeland.com>
+Acked-by: Nick Kossifidis <mickfl...@gmail.com>
+Signed-off-by: John W. Linville <linvi...@tuxdriver.com>
+Signed-off-by: Jonathan Nieder <jrnie...@gmail.com>
+---
+ drivers/net/wireless/ath/ath5k/ath5k.h | 13 +++
+ drivers/net/wireless/ath/ath5k/attach.c | 2 +
+ drivers/net/wireless/ath/ath5k/phy.c | 193 +++++++++++++++++++++----------
+ drivers/net/wireless/ath/ath5k/reg.h | 11 +-
+ drivers/net/wireless/ath/ath5k/reset.c | 17 +--
+ 5 files changed, 152 insertions(+), 84 deletions(-)
+
+diff --git a/drivers/net/wireless/ath/ath5k/ath5k.h
b/drivers/net/wireless/ath/ath5k/ath5k.h
+index 2c79c78ef2d7..0601236e27f2 100644
+--- a/drivers/net/wireless/ath/ath5k/ath5k.h
++++ b/drivers/net/wireless/ath/ath5k/ath5k.h
+@@ -204,6 +204,7 @@
+ #define AR5K_TUNE_CWMAX_11B 1023
+ #define AR5K_TUNE_CWMAX_XR 7
+ #define AR5K_TUNE_NOISE_FLOOR -72
++#define AR5K_TUNE_CCA_MAX_GOOD_VALUE -95
+ #define AR5K_TUNE_MAX_TXPOWER 63
+ #define AR5K_TUNE_DEFAULT_TXPOWER 25
+ #define AR5K_TUNE_TPC_TXPOWER false
+@@ -1011,6 +1012,14 @@ struct ath5k_capabilities {
+ } cap_queues;
+ };
+
++/* size of noise floor history (keep it a power of two) */
++#define ATH5K_NF_CAL_HIST_MAX 8
++struct ath5k_nfcal_hist
++{
++ s16 index; /* current index into nfval */
++ s16 nfval[ATH5K_NF_CAL_HIST_MAX]; /* last few noise floors */
++};
++
+
+ /***************************************\
+ HARDWARE ABSTRACTION LAYER STRUCTURE
+@@ -1124,6 +1133,8 @@ struct ath5k_hw {
+ struct ieee80211_channel r_last_channel;
+ } ah_radar;
+
++ struct ath5k_nfcal_hist ah_nfcal_hist;
++
+ /* noise floor from last periodic calibration */
+ s32 ah_noise_floor;
+
+@@ -1287,8 +1298,10 @@ extern int ath5k_hw_rfgain_opt_init(struct ath5k_hw
*ah);
+ extern bool ath5k_channel_ok(struct ath5k_hw *ah, u16 freq, unsigned int
flags);
+ extern int ath5k_hw_channel(struct ath5k_hw *ah, struct ieee80211_channel
*channel);
+ /* PHY calibration */
++void ath5k_hw_init_nfcal_hist(struct ath5k_hw *ah);
+ extern int ath5k_hw_phy_calibrate(struct ath5k_hw *ah, struct
ieee80211_channel *channel);
+ extern int ath5k_hw_noise_floor_calibration(struct ath5k_hw *ah, short freq);
++extern s16 ath5k_hw_get_noise_floor(struct ath5k_hw *ah);
+ extern void ath5k_hw_calibration_poll(struct ath5k_hw *ah);
+ /* Spur mitigation */
+ bool ath5k_hw_chan_has_spur_noise(struct ath5k_hw *ah,
+diff --git a/drivers/net/wireless/ath/ath5k/attach.c
b/drivers/net/wireless/ath/ath5k/attach.c
+index b5ea906cd7c8..591f54a54a46 100644
+--- a/drivers/net/wireless/ath/ath5k/attach.c
++++ b/drivers/net/wireless/ath/ath5k/attach.c
+@@ -344,6 +344,8 @@ struct ath5k_hw *ath5k_hw_attach(struct ath5k_softc *sc)
+
+ ath5k_hw_rfgain_opt_init(ah);
+
++ ath5k_hw_init_nfcal_hist(ah);
++
+ /* turn on HW LEDs */
+ ath5k_hw_set_ledstate(ah, AR5K_LED_INIT);
+
+diff --git a/drivers/net/wireless/ath/ath5k/phy.c
b/drivers/net/wireless/ath/ath5k/phy.c
+index 9d676474839d..721ec5ee381d 100644
+--- a/drivers/net/wireless/ath/ath5k/phy.c
++++ b/drivers/net/wireless/ath/ath5k/phy.c
+@@ -1124,77 +1124,148 @@ ath5k_hw_calibration_poll(struct ath5k_hw *ah)
+ ah->ah_swi_mask = AR5K_SWI_FULL_CALIBRATION;
+ AR5K_REG_ENABLE_BITS(ah, AR5K_CR, AR5K_CR_SWI);
+ }
++}
+
++static int sign_extend(int val, const int nbits)
++{
++ int order = BIT(nbits-1);
++ return (val ^ order) - order;
+ }
+
+-/**
+- * ath5k_hw_noise_floor_calibration - perform PHY noise floor calibration
+- *
+- * @ah: struct ath5k_hw pointer we are operating on
+- * @freq: the channel frequency, just used for error logging
+- *
+- * This function performs a noise floor calibration of the PHY and waits for
+- * it to complete. Then the noise floor value is compared to some maximum
+- * noise floor we consider valid.
+- *
+- * Note that this is different from what the madwifi HAL does: it reads the
+- * noise floor and afterwards initiates the calibration. Since the noise floor
+- * calibration can take some time to finish, depending on the current channel
+- * use, that avoids the occasional timeout warnings we are seeing now.
+- *
+- * See the following link for an Atheros patent on noise floor calibration:
+- * http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL \
+- * &p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=7245893.PN.&OS=PN/7
++static s32 ath5k_hw_read_measured_noise_floor(struct ath5k_hw *ah)
++{
++ s32 val;
++
++ val = ath5k_hw_reg_read(ah, AR5K_PHY_NF);
++ return sign_extend(AR5K_REG_MS(val, AR5K_PHY_NF_MINCCA_PWR), 9);
++}
++
++void ath5k_hw_init_nfcal_hist(struct ath5k_hw *ah)
++{
++ int i;
++
++ ah->ah_nfcal_hist.index = 0;
++ for (i = 0; i < ATH5K_NF_CAL_HIST_MAX; i++)
++ ah->ah_nfcal_hist.nfval[i] = AR5K_TUNE_CCA_MAX_GOOD_VALUE;
++}
++
++static void ath5k_hw_update_nfcal_hist(struct ath5k_hw *ah, s16 noise_floor)
++{
++ struct ath5k_nfcal_hist *hist = &ah->ah_nfcal_hist;
++ hist->index = (hist->index + 1) & (ATH5K_NF_CAL_HIST_MAX-1);
++ hist->nfval[hist->index] = noise_floor;
++}
++
++static s16 ath5k_hw_get_median_noise_floor(struct ath5k_hw *ah)
++{
++ s16 sort[ATH5K_NF_CAL_HIST_MAX];
++ s16 tmp;
++ int i, j;
++
++ memcpy(sort, ah->ah_nfcal_hist.nfval, sizeof(sort));
++ for (i = 0; i < ATH5K_NF_CAL_HIST_MAX - 1; i++) {
++ for (j = 1; j < ATH5K_NF_CAL_HIST_MAX - i; j++) {
++ if (sort[j] > sort[j-1]) {
++ tmp = sort[j];
++ sort[j] = sort[j-1];
++ sort[j-1] = tmp;
++ }
++ }
++ }
++ for (i = 0; i < ATH5K_NF_CAL_HIST_MAX; i++) {
++ ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_CALIBRATE,
++ "cal %d:%d\n", i, sort[i]);
++ }
++ return sort[(ATH5K_NF_CAL_HIST_MAX-1) / 2];
++}
++
++/*
++ * When we tell the hardware to perform a noise floor calibration
++ * by setting the AR5K_PHY_AGCCTL_NF bit, it will periodically
++ * sample-and-hold the minimum noise level seen at the antennas.
++ * This value is then stored in a ring buffer of recently measured
++ * noise floor values so we have a moving window of the last few
++ * samples.
+ *
+- * XXX: Since during noise floor calibration antennas are detached according
to
+- * the patent, we should stop tx queues here.
++ * The median of the values in the history is then loaded into the
++ * hardware for its own use for RSSI and CCA measurements.
+ */
+-int
+-ath5k_hw_noise_floor_calibration(struct ath5k_hw *ah, short freq)
++void ath5k_hw_update_noise_floor(struct ath5k_hw *ah)
+ {
+- int ret;
+- unsigned int i;
+- s32 noise_floor;
++ struct ath5k_eeprom_info *ee = &ah->ah_capabilities.cap_eeprom;
++ u32 val;
++ s16 nf, threshold;
++ u8 ee_mode;
++
++ /* keep last value if calibration hasn't completed */
++ if (ath5k_hw_reg_read(ah, AR5K_PHY_AGCCTL) & AR5K_PHY_AGCCTL_NF) {
++ ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_CALIBRATE,
++ "NF did not complete in calibration window\n");
++
++ return;
++ }
++
++ switch (ah->ah_current_channel->hw_value & CHANNEL_MODES) {
++ case CHANNEL_A:
++ case CHANNEL_T:
++ case CHANNEL_XR:
++ ee_mode = AR5K_EEPROM_MODE_11A;
++ break;
++ case CHANNEL_G:
++ case CHANNEL_TG:
++ ee_mode = AR5K_EEPROM_MODE_11G;
++ break;
++ default:
++ case CHANNEL_B:
++ ee_mode = AR5K_EEPROM_MODE_11B;
++ break;
++ }
++
++
++ /* completed NF calibration, test threshold */
++ nf = ath5k_hw_read_measured_noise_floor(ah);
++ threshold = ee->ee_noise_floor_thr[ee_mode];
++
++ if (nf > threshold) {
++ ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_CALIBRATE,
++ "noise floor failure detected; "
++ "read %d, threshold %d\n",
++ nf, threshold);
++
++ nf = AR5K_TUNE_CCA_MAX_GOOD_VALUE;
++ }
++
++ ath5k_hw_update_nfcal_hist(ah, nf);
++ nf = ath5k_hw_get_median_noise_floor(ah);
++
++ /* load noise floor (in .5 dBm) so the hardware will use it */
++ val = ath5k_hw_reg_read(ah, AR5K_PHY_NF) & ~AR5K_PHY_NF_M;
++ val |= (nf * 2) & AR5K_PHY_NF_M;
++ ath5k_hw_reg_write(ah, val, AR5K_PHY_NF);
++
++ AR5K_REG_MASKED_BITS(ah, AR5K_PHY_AGCCTL, AR5K_PHY_AGCCTL_NF,
++ ~(AR5K_PHY_AGCCTL_NF_EN | AR5K_PHY_AGCCTL_NF_NOUPDATE));
++
++ ath5k_hw_register_timeout(ah, AR5K_PHY_AGCCTL, AR5K_PHY_AGCCTL_NF,
++ 0, false);
+
+ /*
+- * Enable noise floor calibration
++ * Load a high max CCA Power value (-50 dBm in .5 dBm units)
++ * so that we're not capped by the median we just loaded.
++ * This will be used as the initial value for the next noise
++ * floor calibration.
+ */
++ val = (val & ~AR5K_PHY_NF_M) | ((-50 * 2) & AR5K_PHY_NF_M);
++ ath5k_hw_reg_write(ah, val, AR5K_PHY_NF);
+ AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGCCTL,
+- AR5K_PHY_AGCCTL_NF);
++ AR5K_PHY_AGCCTL_NF_EN |
++ AR5K_PHY_AGCCTL_NF_NOUPDATE |
++ AR5K_PHY_AGCCTL_NF);
+
+- ret = ath5k_hw_register_timeout(ah, AR5K_PHY_AGCCTL,
+- AR5K_PHY_AGCCTL_NF, 0, false);
+- if (ret) {
+- ATH5K_ERR(ah->ah_sc,
+- "noise floor calibration timeout (%uMHz)\n", freq);
+- return -EAGAIN;
+- }
++ ah->ah_noise_floor = nf;
+
+- /* Wait until the noise floor is calibrated and read the value */
+- for (i = 20; i > 0; i--) {
+- mdelay(1);
+- noise_floor = ath5k_hw_reg_read(ah, AR5K_PHY_NF);
+- noise_floor = AR5K_PHY_NF_RVAL(noise_floor);
+- if (noise_floor & AR5K_PHY_NF_ACTIVE) {
+- noise_floor = AR5K_PHY_NF_AVAL(noise_floor);
+-
+- if (noise_floor <= AR5K_TUNE_NOISE_FLOOR)
+- break;
+- }
+- }
+-
+- ATH5K_DBG_UNLIMIT(ah->ah_sc, ATH5K_DEBUG_CALIBRATE,
+- "noise floor %d\n", noise_floor);
+-
+- if (noise_floor > AR5K_TUNE_NOISE_FLOOR) {
+- ATH5K_ERR(ah->ah_sc,
+- "noise floor calibration failed (%uMHz)\n", freq);
+- return -EAGAIN;
+- }
+-
+- ah->ah_noise_floor = noise_floor;
+-
+- return 0;
++ ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_CALIBRATE,
++ "noise floor calibrated: %d\n", nf);
+ }
+
+ /*
+@@ -1287,7 +1358,7 @@ static int ath5k_hw_rf5110_calibrate(struct ath5k_hw *ah,
+ return ret;
+ }
+
+- ath5k_hw_noise_floor_calibration(ah, channel->center_freq);
++ ath5k_hw_update_noise_floor(ah);
+
+ /*
+ * Re-enable RX/TX and beacons
+@@ -1360,7 +1431,7 @@ done:
+ * since noise floor calibration interrupts rx path while I/Q
+ * calibration doesn't. We don't need to run noise floor calibration
+ * as often as I/Q calibration.*/
+- ath5k_hw_noise_floor_calibration(ah, channel->center_freq);
++ ath5k_hw_update_noise_floor(ah);
+
+ /* Initiate a gain_F calibration */
+ ath5k_hw_request_rfgain_probe(ah);
+diff --git a/drivers/net/wireless/ath/ath5k/reg.h
b/drivers/net/wireless/ath/ath5k/reg.h
+index c63ea6afd96f..186469eb4132 100644
+--- a/drivers/net/wireless/ath/ath5k/reg.h
++++ b/drivers/net/wireless/ath/ath5k/reg.h
+@@ -2039,17 +2039,14 @@
+ #define AR5K_PHY_AGCCTL_NF_NOUPDATE 0x00020000 /* Don't update
nf automaticaly */
+
+ /*
+- * PHY noise floor status register
++ * PHY noise floor status register (CCA = Clear Channel Assessment)
+ */
+ #define AR5K_PHY_NF 0x9864 /* Register
address */
+-#define AR5K_PHY_NF_M 0x000001ff /* Noise floor mask */
+-#define AR5K_PHY_NF_ACTIVE 0x00000100 /* Noise floor
calibration still active */
+-#define AR5K_PHY_NF_RVAL(_n) (((_n) >> 19) & AR5K_PHY_NF_M)
+-#define AR5K_PHY_NF_AVAL(_n) (-((_n) ^ AR5K_PHY_NF_M) + 1)
+-#define AR5K_PHY_NF_SVAL(_n) (((_n) & AR5K_PHY_NF_M) | (1 << 9))
++#define AR5K_PHY_NF_M 0x000001ff /* Noise floor, written
to hardware in 1/2 dBm units */
++#define AR5K_PHY_NF_SVAL(_n) (((_n) & AR5K_PHY_NF_M) | (1 << 9))
+ #define AR5K_PHY_NF_THRESH62 0x0007f000 /* Thresh62
-check ANI patent- (field) */
+ #define AR5K_PHY_NF_THRESH62_S 12
+-#define AR5K_PHY_NF_MINCCA_PWR 0x0ff80000 /* ??? */
++#define AR5K_PHY_NF_MINCCA_PWR 0x0ff80000 /* Minimum
measured noise level, read from hardware in 1 dBm units */
+ #define AR5K_PHY_NF_MINCCA_PWR_S 19
+
+ /*
+diff --git a/drivers/net/wireless/ath/ath5k/reset.c
b/drivers/net/wireless/ath/ath5k/reset.c
+index 257ea18c849f..8fd6ec2e522b 100644
+--- a/drivers/net/wireless/ath/ath5k/reset.c
++++ b/drivers/net/wireless/ath/ath5k/reset.c
+@@ -1289,7 +1289,7 @@ int ath5k_hw_reset(struct ath5k_hw *ah, enum
nl80211_iftype op_mode,
+ * out and/or noise floor calibration might timeout.
+ */
+ AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGCCTL,
+- AR5K_PHY_AGCCTL_CAL);
++ AR5K_PHY_AGCCTL_CAL | AR5K_PHY_AGCCTL_NF);
+
+ /* At the same time start I/Q calibration for QAM constellation
+ * -no need for CCK- */
+@@ -1310,21 +1310,6 @@ int ath5k_hw_reset(struct ath5k_hw *ah, enum
nl80211_iftype op_mode,
+ channel->center_freq);
+ }
+
+- /*
+- * If we run NF calibration before AGC, it always times out.
+- * Binary HAL starts NF and AGC calibration at the same time
+- * and only waits for AGC to finish. Also if AGC or NF cal.
+- * times out, reset doesn't fail on binary HAL. I believe
+- * that's wrong because since rx path is routed to a detector,
+- * if cal. doesn't finish we won't have RX. Sam's HAL for AR5210/5211
+- * enables noise floor calibration after offset calibration and if noise
+- * floor calibration fails, reset fails. I believe that's
+- * a better approach, we just need to find a polling interval
+- * that suits best, even if reset continues we need to make
+- * sure that rx path is ready.
+- */
+- ath5k_hw_noise_floor_calibration(ah, channel->center_freq);
+-
+ /* Restore antenna mode */
+ ath5k_hw_set_antenna_mode(ah, ah->ah_ant_mode);
+
+--
+1.7.10
+
Index: debian/patches/series/46
===================================================================
--- debian/patches/series/46 (revision 0)
+++ debian/patches/series/46 (working copy)
@@ -0,0 +1,2 @@
++ bugfix/all/ath5k-initialize-default-noise-floor.patch
++ bugfix/all/ath5k-use-noise-calibration-from-madwifi-hal.patch
