2009-08-10 00:29:05

by Nick Kossifidis

[permalink] [raw]
Subject: [PATCH 3/5] ath5k: Wakeup fixes

* Don't put chip to full sleep because there are problems during
wakeup. Instead hold MAC/Baseband on warm reset state via a new
function ath5k_hw_on_hold.

* Minor cleanups

Signed-off-by: Nick Kossifidis <[email protected]>
Tested-by: Ben Greear <[email protected]>
Tested-by: Johannes Stezenbach <[email protected]>

---
drivers/net/wireless/ath/ath5k/ath5k.h | 1 +
drivers/net/wireless/ath/ath5k/attach.c | 2 +-
drivers/net/wireless/ath/ath5k/base.c | 44 +++++----
drivers/net/wireless/ath/ath5k/reset.c | 155 +++++++++++++++++++++++--------
4 files changed, 140 insertions(+), 62 deletions(-)

diff --git a/drivers/net/wireless/ath/ath5k/ath5k.h b/drivers/net/wireless/ath/ath5k/ath5k.h
index 9137511..1047a6c 100644
--- a/drivers/net/wireless/ath/ath5k/ath5k.h
+++ b/drivers/net/wireless/ath/ath5k/ath5k.h
@@ -1157,6 +1157,7 @@ extern void ath5k_unregister_leds(struct ath5k_softc *sc);

/* Reset Functions */
extern int ath5k_hw_nic_wakeup(struct ath5k_hw *ah, int flags, bool initial);
+extern int ath5k_hw_on_hold(struct ath5k_hw *ah);
extern int ath5k_hw_reset(struct ath5k_hw *ah, enum nl80211_iftype op_mode, struct ieee80211_channel *channel, bool change_channel);
/* Power management functions */
extern int ath5k_hw_set_power(struct ath5k_hw *ah, enum ath5k_power_mode mode, bool set_chip, u16 sleep_duration);
diff --git a/drivers/net/wireless/ath/ath5k/attach.c b/drivers/net/wireless/ath/ath5k/attach.c
index 6263065..238eeb7 100644
--- a/drivers/net/wireless/ath/ath5k/attach.c
+++ b/drivers/net/wireless/ath/ath5k/attach.c
@@ -145,7 +145,7 @@ struct ath5k_hw *ath5k_hw_attach(struct ath5k_softc *sc, u8 mac_version)
goto err_free;

/* Bring device out of sleep and reset it's units */
- ret = ath5k_hw_nic_wakeup(ah, CHANNEL_B, true);
+ ret = ath5k_hw_nic_wakeup(ah, 0, true);
if (ret)
goto err_free;

diff --git a/drivers/net/wireless/ath/ath5k/base.c b/drivers/net/wireless/ath/ath5k/base.c
index 5d50285..0370cba 100644
--- a/drivers/net/wireless/ath/ath5k/base.c
+++ b/drivers/net/wireless/ath/ath5k/base.c
@@ -2446,27 +2446,29 @@ ath5k_stop_hw(struct ath5k_softc *sc)
ret = ath5k_stop_locked(sc);
if (ret == 0 && !test_bit(ATH_STAT_INVALID, sc->status)) {
/*
- * Set the chip in full sleep mode. Note that we are
- * careful to do this only when bringing the interface
- * completely to a stop. When the chip is in this state
- * it must be carefully woken up or references to
- * registers in the PCI clock domain may freeze the bus
- * (and system). This varies by chip and is mostly an
- * issue with newer parts that go to sleep more quickly.
- */
- if (sc->ah->ah_mac_srev >= 0x78) {
- /*
- * XXX
- * don't put newer MAC revisions > 7.8 to sleep because
- * of the above mentioned problems
- */
- ATH5K_DBG(sc, ATH5K_DEBUG_RESET, "mac version > 7.8, "
- "not putting device to sleep\n");
- } else {
- ATH5K_DBG(sc, ATH5K_DEBUG_RESET,
- "putting device to full sleep\n");
- ath5k_hw_set_power(sc->ah, AR5K_PM_FULL_SLEEP, true, 0);
- }
+ * Don't set the card in full sleep mode!
+ *
+ * a) When the device is in this state it must be carefully
+ * woken up or references to registers in the PCI clock
+ * domain may freeze the bus (and system). This varies
+ * by chip and is mostly an issue with newer parts
+ * (madwifi sources mentioned srev >= 0x78) that go to
+ * sleep more quickly.
+ *
+ * b) On older chips full sleep results a weird behaviour
+ * during wakeup. I tested various cards with srev < 0x78
+ * and they don't wake up after module reload, a second
+ * module reload is needed to bring the card up again.
+ *
+ * Until we figure out what's going on don't enable
+ * full chip reset on any chip (this is what Legacy HAL
+ * and Sam's HAL do anyway). Instead Perform a full reset
+ * on the device (same as initial state after attach) and
+ * leave it idle (keep MAC/BB on warm reset) */
+ ret = ath5k_hw_on_hold(sc->ah);
+
+ ATH5K_DBG(sc, ATH5K_DEBUG_RESET,
+ "putting device to sleep\n");
}
ath5k_txbuf_free(sc, sc->bbuf);

diff --git a/drivers/net/wireless/ath/ath5k/reset.c b/drivers/net/wireless/ath/ath5k/reset.c
index 86733fd..34e13c7 100644
--- a/drivers/net/wireless/ath/ath5k/reset.c
+++ b/drivers/net/wireless/ath/ath5k/reset.c
@@ -258,29 +258,35 @@ int ath5k_hw_set_power(struct ath5k_hw *ah, enum ath5k_power_mode mode,
if (!set_chip)
goto commit;

- /* Preserve sleep duration */
data = ath5k_hw_reg_read(ah, AR5K_SLEEP_CTL);
+
+ /* If card is down we 'll get 0xffff... so we
+ * need to clean this up before we write the register
+ */
if (data & 0xffc00000)
data = 0;
else
- data = data & 0xfffcffff;
+ /* Preserve sleep duration etc */
+ data = data & ~AR5K_SLEEP_CTL_SLE;

- ath5k_hw_reg_write(ah, data, AR5K_SLEEP_CTL);
+ ath5k_hw_reg_write(ah, data | AR5K_SLEEP_CTL_SLE_WAKE,
+ AR5K_SLEEP_CTL);
udelay(15);

- for (i = 50; i > 0; i--) {
+ for (i = 200; i > 0; i--) {
/* Check if the chip did wake up */
if ((ath5k_hw_reg_read(ah, AR5K_PCICFG) &
AR5K_PCICFG_SPWR_DN) == 0)
break;

/* Wait a bit and retry */
- udelay(200);
- ath5k_hw_reg_write(ah, data, AR5K_SLEEP_CTL);
+ udelay(50);
+ ath5k_hw_reg_write(ah, data | AR5K_SLEEP_CTL_SLE_WAKE,
+ AR5K_SLEEP_CTL);
}

/* Fail if the chip didn't wake up */
- if (i <= 0)
+ if (i == 0)
return -EIO;

break;
@@ -296,6 +302,64 @@ commit:
}

/*
+ * Put device on hold
+ *
+ * Put MAC and Baseband on warm reset and
+ * keep that state (don't clean sleep control
+ * register). After this MAC and Baseband are
+ * disabled and a full reset is needed to come
+ * back. This way we save as much power as possible
+ * without puting the card on full sleep.
+ */
+int ath5k_hw_on_hold(struct ath5k_hw *ah)
+{
+ struct pci_dev *pdev = ah->ah_sc->pdev;
+ u32 bus_flags;
+ int ret;
+
+ /* Make sure device is awake */
+ ret = ath5k_hw_set_power(ah, AR5K_PM_AWAKE, true, 0);
+ if (ret) {
+ ATH5K_ERR(ah->ah_sc, "failed to wakeup the MAC Chip\n");
+ return ret;
+ }
+
+ /*
+ * Put chipset on warm reset...
+ *
+ * Note: puting PCI core on warm reset on PCI-E cards
+ * results card to hang and always return 0xffff... so
+ * we ingore that flag for PCI-E cards. On PCI cards
+ * this flag gets cleared after 64 PCI clocks.
+ */
+ bus_flags = (pdev->is_pcie) ? 0 : AR5K_RESET_CTL_PCI;
+
+ if (ah->ah_version == AR5K_AR5210) {
+ ret = ath5k_hw_nic_reset(ah, AR5K_RESET_CTL_PCU |
+ AR5K_RESET_CTL_MAC | AR5K_RESET_CTL_DMA |
+ AR5K_RESET_CTL_PHY | AR5K_RESET_CTL_PCI);
+ mdelay(2);
+ } else {
+ ret = ath5k_hw_nic_reset(ah, AR5K_RESET_CTL_PCU |
+ AR5K_RESET_CTL_BASEBAND | bus_flags);
+ }
+
+ if (ret) {
+ ATH5K_ERR(ah->ah_sc, "failed to put device on warm reset\n");
+ return -EIO;
+ }
+
+ /* ...wakeup again!*/
+ ret = ath5k_hw_set_power(ah, AR5K_PM_AWAKE, true, 0);
+ if (ret) {
+ ATH5K_ERR(ah->ah_sc, "failed to put device on hold\n");
+ return ret;
+ }
+
+ return ret;
+}
+
+/*
* Bring up MAC + PHY Chips and program PLL
* TODO: Half/Quarter rate support
*/
@@ -318,6 +382,50 @@ int ath5k_hw_nic_wakeup(struct ath5k_hw *ah, int flags, bool initial)
return ret;
}

+ /*
+ * Put chipset on warm reset...
+ *
+ * Note: puting PCI core on warm reset on PCI-E cards
+ * results card to hang and always return 0xffff... so
+ * we ingore that flag for PCI-E cards. On PCI cards
+ * this flag gets cleared after 64 PCI clocks.
+ */
+ bus_flags = (pdev->is_pcie) ? 0 : AR5K_RESET_CTL_PCI;
+
+ if (ah->ah_version == AR5K_AR5210) {
+ ret = ath5k_hw_nic_reset(ah, AR5K_RESET_CTL_PCU |
+ AR5K_RESET_CTL_MAC | AR5K_RESET_CTL_DMA |
+ AR5K_RESET_CTL_PHY | AR5K_RESET_CTL_PCI);
+ mdelay(2);
+ } else {
+ ret = ath5k_hw_nic_reset(ah, AR5K_RESET_CTL_PCU |
+ AR5K_RESET_CTL_BASEBAND | bus_flags);
+ }
+
+ if (ret) {
+ ATH5K_ERR(ah->ah_sc, "failed to reset the MAC Chip\n");
+ return -EIO;
+ }
+
+ /* ...wakeup again!...*/
+ ret = ath5k_hw_set_power(ah, AR5K_PM_AWAKE, true, 0);
+ if (ret) {
+ ATH5K_ERR(ah->ah_sc, "failed to resume the MAC Chip\n");
+ return ret;
+ }
+
+ /* ...clear reset control register and pull device out of
+ * warm reset */
+ if (ath5k_hw_nic_reset(ah, 0)) {
+ ATH5K_ERR(ah->ah_sc, "failed to warm reset the MAC Chip\n");
+ return -EIO;
+ }
+
+ /* On initialization skip PLL programming since we don't have
+ * a channel / mode set yet */
+ if (initial)
+ return 0;
+
if (ah->ah_version != AR5K_AR5210) {
/*
* Get channel mode flags
@@ -383,39 +491,6 @@ int ath5k_hw_nic_wakeup(struct ath5k_hw *ah, int flags, bool initial)
AR5K_PHY_TURBO);
}

- /* reseting PCI on PCI-E cards results card to hang
- * and always return 0xffff... so we ingore that flag
- * for PCI-E cards */
- bus_flags = (pdev->is_pcie) ? 0 : AR5K_RESET_CTL_PCI;
-
- /* Reset chipset */
- if (ah->ah_version == AR5K_AR5210) {
- ret = ath5k_hw_nic_reset(ah, AR5K_RESET_CTL_PCU |
- AR5K_RESET_CTL_MAC | AR5K_RESET_CTL_DMA |
- AR5K_RESET_CTL_PHY | AR5K_RESET_CTL_PCI);
- mdelay(2);
- } else {
- ret = ath5k_hw_nic_reset(ah, AR5K_RESET_CTL_PCU |
- AR5K_RESET_CTL_BASEBAND | bus_flags);
- }
- if (ret) {
- ATH5K_ERR(ah->ah_sc, "failed to reset the MAC Chip\n");
- return -EIO;
- }
-
- /* ...wakeup again!*/
- ret = ath5k_hw_set_power(ah, AR5K_PM_AWAKE, true, 0);
- if (ret) {
- ATH5K_ERR(ah->ah_sc, "failed to resume the MAC Chip\n");
- return ret;
- }
-
- /* ...final warm reset */
- if (ath5k_hw_nic_reset(ah, 0)) {
- ATH5K_ERR(ah->ah_sc, "failed to warm reset the MAC Chip\n");
- return -EIO;
- }
-
if (ah->ah_version != AR5K_AR5210) {

/* ...update PLL if needed */