iwlcore: register locks

Add new lock to be used when accessing some registers. Also move
    the register lock and iwl_grab_nic_access inside the function for register access. This
    will prevent from forgetting to hold locks and nic access in the right way and make code
    easier to maintain.

    We over use the priv->lock spin lock and I guess we need to add new
    one for Tx queue after that we might need to change most of these lock to
    BH and just keep priv->lock as irq type.

Signed-off-by: Mohamed Abbas <mohamed.abbas@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 159 insertions, 94 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-io.h b/drivers/net/wireless/iwlwifi/iwl-io.h
index 083ea1ffbe8..d30cb0275d1 100644
--- a/drivers/net/wireless/iwlwifi/iwl-io.h
+++ b/drivers/net/wireless/iwlwifi/iwl-io.h
@@ -131,9 +131,23 @@ static inline void __iwl_set_bit(const char *f, u32 l,
 	IWL_DEBUG_IO(priv, "set_bit(0x%08X, 0x%08X) = 0x%08X\n", reg, mask, val);
 	_iwl_write32(priv, reg, val);
 }
-#define iwl_set_bit(p, r, m) __iwl_set_bit(__FILE__, __LINE__, p, r, m)
+static inline void iwl_set_bit(struct iwl_priv *p, u32 r, u32 m)
+{
+	unsigned long reg_flags;
+
+	spin_lock_irqsave(&p->reg_lock, reg_flags);
+	__iwl_set_bit(__FILE__, __LINE__, p, r, m);
+	spin_unlock_irqrestore(&p->reg_lock, reg_flags);
+}
 #else
-#define iwl_set_bit(p, r, m) _iwl_set_bit(p, r, m)
+static inline void iwl_set_bit(struct iwl_priv *p, u32 r, u32 m)
+{
+	unsigned long reg_flags;
+
+	spin_lock_irqsave(&p->reg_lock, reg_flags);
+	_iwl_set_bit(p, r, m);
+	spin_unlock_irqrestore(&p->reg_lock, reg_flags);
+}
 #endif
 
 static inline void _iwl_clear_bit(struct iwl_priv *priv, u32 reg, u32 mask)
@@ -148,19 +162,30 @@ static inline void __iwl_clear_bit(const char *f, u32 l,
 	IWL_DEBUG_IO(priv, "clear_bit(0x%08X, 0x%08X) = 0x%08X\n", reg, mask, val);
 	_iwl_write32(priv, reg, val);
 }
-#define iwl_clear_bit(p, r, m) __iwl_clear_bit(__FILE__, __LINE__, p, r, m)
+static inline void iwl_clear_bit(struct iwl_priv *p, u32 r, u32 m)
+{
+	unsigned long reg_flags;
+
+	spin_lock_irqsave(&p->reg_lock, reg_flags);
+	__iwl_clear_bit(__FILE__, __LINE__, p, r, m);
+	spin_unlock_irqrestore(&p->reg_lock, reg_flags);
+}
 #else
-#define iwl_clear_bit(p, r, m) _iwl_clear_bit(p, r, m)
+static inline void iwl_clear_bit(struct iwl_priv *p, u32 r, u32 m)
+{
+	unsigned long reg_flags;
+
+	spin_lock_irqsave(&p->reg_lock, reg_flags);
+	_iwl_clear_bit(p, r, m);
+	spin_unlock_irqrestore(&p->reg_lock, reg_flags);
+}
 #endif
 
 static inline int _iwl_grab_nic_access(struct iwl_priv *priv)
 {
 	int ret;
 	u32 val;
-#ifdef CONFIG_IWLWIFI_DEBUG
-	if (atomic_read(&priv->restrict_refcnt))
-		return 0;
-#endif
+
 	/* this bit wakes up the NIC */
 	_iwl_set_bit(priv, CSR_GP_CNTRL, CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
 	ret = _iwl_poll_bit(priv, CSR_GP_CNTRL,
@@ -170,12 +195,10 @@ static inline int _iwl_grab_nic_access(struct iwl_priv *priv)
 	if (ret < 0) {
 		val = _iwl_read32(priv, CSR_GP_CNTRL);
 		IWL_ERR(priv, "MAC is in deep sleep!.  CSR_GP_CNTRL = 0x%08X\n", val);
+		_iwl_write32(priv, CSR_RESET, CSR_RESET_REG_FLAG_FORCE_NMI);
 		return -EIO;
 	}
 
-#ifdef CONFIG_IWLWIFI_DEBUG
-	atomic_inc(&priv->restrict_refcnt);
-#endif
 	return 0;
 }
 
@@ -183,9 +206,6 @@ static inline int _iwl_grab_nic_access(struct iwl_priv *priv)
 static inline int __iwl_grab_nic_access(const char *f, u32 l,
 					       struct iwl_priv *priv)
 {
-	if (atomic_read(&priv->restrict_refcnt))
-		IWL_ERR(priv, "Grabbing access while already held %s %d.\n", f, l);
-
 	IWL_DEBUG_IO(priv, "grabbing nic access - %s %d\n", f, l);
 	return _iwl_grab_nic_access(priv);
 }
@@ -198,18 +218,13 @@ static inline int __iwl_grab_nic_access(const char *f, u32 l,
 
 static inline void _iwl_release_nic_access(struct iwl_priv *priv)
 {
-#ifdef CONFIG_IWLWIFI_DEBUG
-	if (atomic_dec_and_test(&priv->restrict_refcnt))
-#endif
-		_iwl_clear_bit(priv, CSR_GP_CNTRL,
-			       CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
+	_iwl_clear_bit(priv, CSR_GP_CNTRL,
+			CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
 }
 #ifdef CONFIG_IWLWIFI_DEBUG
 static inline void __iwl_release_nic_access(const char *f, u32 l,
 					    struct iwl_priv *priv)
 {
-	if (atomic_read(&priv->restrict_refcnt) <= 0)
-		IWL_ERR(priv, "Release unheld nic access at line %s %d.\n", f, l);
 
 	IWL_DEBUG_IO(priv, "releasing nic access - %s %d\n", f, l);
 	_iwl_release_nic_access(priv);
@@ -230,16 +245,37 @@ static inline u32 __iwl_read_direct32(const char *f, u32 l,
 					struct iwl_priv *priv, u32 reg)
 {
 	u32 value = _iwl_read_direct32(priv, reg);
-	if (!atomic_read(&priv->restrict_refcnt))
-		IWL_ERR(priv, "Nic access not held from %s %d\n", f, l);
 	IWL_DEBUG_IO(priv, "read_direct32(0x%4X) = 0x%08x - %s %d \n", reg, value,
 		     f, l);
 	return value;
 }
-#define iwl_read_direct32(priv, reg) \
-	__iwl_read_direct32(__FILE__, __LINE__, priv, reg)
+static inline u32 iwl_read_direct32(struct iwl_priv *priv, u32 reg)
+{
+	u32 value;
+	unsigned long reg_flags;
+
+	spin_lock_irqsave(&priv->reg_lock, reg_flags);
+	iwl_grab_nic_access(priv);
+	value = __iwl_read_direct32(__FILE__, __LINE__, priv, reg);
+	iwl_release_nic_access(priv);
+	spin_unlock_irqrestore(&priv->reg_lock, reg_flags);
+	return value;
+}
+
 #else
-#define iwl_read_direct32 _iwl_read_direct32
+static inline u32 iwl_read_direct32(struct iwl_priv *priv, u32 reg)
+{
+	u32 value;
+	unsigned long reg_flags;
+
+	spin_lock_irqsave(&priv->reg_lock, reg_flags);
+	iwl_grab_nic_access(priv);
+	value = _iwl_read_direct32(priv, reg);
+	iwl_release_nic_access(priv);
+	spin_unlock_irqrestore(&priv->reg_lock, reg_flags);
+	return value;
+
+}
 #endif
 
 static inline void _iwl_write_direct32(struct iwl_priv *priv,
@@ -247,19 +283,17 @@ static inline void _iwl_write_direct32(struct iwl_priv *priv,
 {
 	_iwl_write32(priv, reg, value);
 }
-#ifdef CONFIG_IWLWIFI_DEBUG
-static void __iwl_write_direct32(const char *f , u32 line,
-				   struct iwl_priv *priv, u32 reg, u32 value)
+static inline void iwl_write_direct32(struct iwl_priv *priv, u32 reg, u32 value)
 {
-	if (!atomic_read(&priv->restrict_refcnt))
-		IWL_ERR(priv, "Nic access not held from %s line %d\n", f, line);
-	_iwl_write_direct32(priv, reg, value);
+	unsigned long reg_flags;
+
+	spin_lock_irqsave(&priv->reg_lock, reg_flags);
+	if (!iwl_grab_nic_access(priv)) {
+		_iwl_write_direct32(priv, reg, value);
+		iwl_release_nic_access(priv);
+	}
+	spin_unlock_irqrestore(&priv->reg_lock, reg_flags);
 }
-#define iwl_write_direct32(priv, reg, value) \
-	__iwl_write_direct32(__func__, __LINE__, priv, reg, value)
-#else
-#define iwl_write_direct32 _iwl_write_direct32
-#endif
 
 static inline void iwl_write_reg_buf(struct iwl_priv *priv,
 					       u32 reg, u32 len, u32 *values)
@@ -268,14 +302,23 @@ static inline void iwl_write_reg_buf(struct iwl_priv *priv,
 
 	if ((priv != NULL) && (values != NULL)) {
 		for (; 0 < len; len -= count, reg += count, values++)
-			_iwl_write_direct32(priv, reg, *values);
+			iwl_write_direct32(priv, reg, *values);
 	}
 }
 
 static inline int _iwl_poll_direct_bit(struct iwl_priv *priv, u32 addr,
 				       u32 mask, int timeout)
 {
-	return _iwl_poll_bit(priv, addr, mask, mask, timeout);
+	int t = 0;
+
+	do {
+		if ((iwl_read_direct32(priv, addr) & mask) == mask)
+			return t;
+		udelay(IWL_POLL_INTERVAL);
+		t += IWL_POLL_INTERVAL;
+	} while (t < timeout);
+
+	return -ETIMEDOUT;
 }
 
 #ifdef CONFIG_IWLWIFI_DEBUG
@@ -305,20 +348,18 @@ static inline u32 _iwl_read_prph(struct iwl_priv *priv, u32 reg)
 	rmb();
 	return _iwl_read_direct32(priv, HBUS_TARG_PRPH_RDAT);
 }
-#ifdef CONFIG_IWLWIFI_DEBUG
-static inline u32 __iwl_read_prph(const char *f, u32 line,
-				  struct iwl_priv *priv, u32 reg)
+static inline u32 iwl_read_prph(struct iwl_priv *priv, u32 reg)
 {
-	if (!atomic_read(&priv->restrict_refcnt))
-		IWL_ERR(priv, "Nic access not held from %s line %d\n", f, line);
-	return _iwl_read_prph(priv, reg);
-}
+	unsigned long reg_flags;
+	u32 val;
 
-#define iwl_read_prph(priv, reg) \
-	__iwl_read_prph(__func__, __LINE__, priv, reg)
-#else
-#define iwl_read_prph _iwl_read_prph
-#endif
+	spin_lock_irqsave(&priv->reg_lock, reg_flags);
+	iwl_grab_nic_access(priv);
+	val = _iwl_read_prph(priv, reg);
+	iwl_release_nic_access(priv);
+	spin_unlock_irqrestore(&priv->reg_lock, reg_flags);
+	return val;
+}
 
 static inline void _iwl_write_prph(struct iwl_priv *priv,
 					     u32 addr, u32 val)
@@ -328,83 +369,107 @@ static inline void _iwl_write_prph(struct iwl_priv *priv,
 	wmb();
 	_iwl_write_direct32(priv, HBUS_TARG_PRPH_WDAT, val);
 }
-#ifdef CONFIG_IWLWIFI_DEBUG
-static inline void __iwl_write_prph(const char *f, u32 line,
-				    struct iwl_priv *priv, u32 addr, u32 val)
+
+static inline void iwl_write_prph(struct iwl_priv *priv, u32 addr, u32 val)
 {
-	if (!atomic_read(&priv->restrict_refcnt))
-		IWL_ERR(priv, "Nic access not held from %s line %d\n", f, line);
-	_iwl_write_prph(priv, addr, val);
-}
+	unsigned long reg_flags;
 
-#define iwl_write_prph(priv, addr, val) \
-	__iwl_write_prph(__func__, __LINE__, priv, addr, val);
-#else
-#define iwl_write_prph _iwl_write_prph
-#endif
+	spin_lock_irqsave(&priv->reg_lock, reg_flags);
+	if (!iwl_grab_nic_access(priv)) {
+		_iwl_write_prph(priv, addr, val);
+		iwl_release_nic_access(priv);
+	}
+	spin_unlock_irqrestore(&priv->reg_lock, reg_flags);
+}
 
 #define _iwl_set_bits_prph(priv, reg, mask) \
 	_iwl_write_prph(priv, reg, (_iwl_read_prph(priv, reg) | mask))
-#ifdef CONFIG_IWLWIFI_DEBUG
-static inline void __iwl_set_bits_prph(const char *f, u32 line,
-				       struct iwl_priv *priv,
-				       u32 reg, u32 mask)
+
+static inline void iwl_set_bits_prph(struct iwl_priv *priv, u32 reg, u32 mask)
 {
-	if (!atomic_read(&priv->restrict_refcnt))
-		IWL_ERR(priv, "Nic access not held from %s line %d\n", f, line);
+	unsigned long reg_flags;
 
+	spin_lock_irqsave(&priv->reg_lock, reg_flags);
+	iwl_grab_nic_access(priv);
 	_iwl_set_bits_prph(priv, reg, mask);
+	iwl_release_nic_access(priv);
+	spin_unlock_irqrestore(&priv->reg_lock, reg_flags);
 }
-#define iwl_set_bits_prph(priv, reg, mask) \
-	__iwl_set_bits_prph(__func__, __LINE__, priv, reg, mask)
-#else
-#define iwl_set_bits_prph _iwl_set_bits_prph
-#endif
 
 #define _iwl_set_bits_mask_prph(priv, reg, bits, mask) \
 	_iwl_write_prph(priv, reg, ((_iwl_read_prph(priv, reg) & mask) | bits))
 
-#ifdef CONFIG_IWLWIFI_DEBUG
-static inline void __iwl_set_bits_mask_prph(const char *f, u32 line,
-		struct iwl_priv *priv, u32 reg, u32 bits, u32 mask)
+static inline void iwl_set_bits_mask_prph(struct iwl_priv *priv, u32 reg,
+				u32 bits, u32 mask)
 {
-	if (!atomic_read(&priv->restrict_refcnt))
-		IWL_ERR(priv, "Nic access not held from %s line %d\n", f, line);
+	unsigned long reg_flags;
+
+	spin_lock_irqsave(&priv->reg_lock, reg_flags);
+	iwl_grab_nic_access(priv);
 	_iwl_set_bits_mask_prph(priv, reg, bits, mask);
+	iwl_release_nic_access(priv);
+	spin_unlock_irqrestore(&priv->reg_lock, reg_flags);
 }
-#define iwl_set_bits_mask_prph(priv, reg, bits, mask) \
-	__iwl_set_bits_mask_prph(__func__, __LINE__, priv, reg, bits, mask)
-#else
-#define iwl_set_bits_mask_prph _iwl_set_bits_mask_prph
-#endif
 
 static inline void iwl_clear_bits_prph(struct iwl_priv
 						 *priv, u32 reg, u32 mask)
 {
-	u32 val = _iwl_read_prph(priv, reg);
+	unsigned long reg_flags;
+	u32 val;
+
+	spin_lock_irqsave(&priv->reg_lock, reg_flags);
+	iwl_grab_nic_access(priv);
+	val = _iwl_read_prph(priv, reg);
 	_iwl_write_prph(priv, reg, (val & ~mask));
+	iwl_release_nic_access(priv);
+	spin_unlock_irqrestore(&priv->reg_lock, reg_flags);
 }
 
 static inline u32 iwl_read_targ_mem(struct iwl_priv *priv, u32 addr)
 {
-	iwl_write_direct32(priv, HBUS_TARG_MEM_RADDR, addr);
+	unsigned long reg_flags;
+	u32 value;
+
+	spin_lock_irqsave(&priv->reg_lock, reg_flags);
+	iwl_grab_nic_access(priv);
+
+	_iwl_write_direct32(priv, HBUS_TARG_MEM_RADDR, addr);
 	rmb();
-	return iwl_read_direct32(priv, HBUS_TARG_MEM_RDAT);
+	value = _iwl_read_direct32(priv, HBUS_TARG_MEM_RDAT);
+
+	iwl_release_nic_access(priv);
+	spin_unlock_irqrestore(&priv->reg_lock, reg_flags);
+	return value;
 }
 
 static inline void iwl_write_targ_mem(struct iwl_priv *priv, u32 addr, u32 val)
 {
-	iwl_write_direct32(priv, HBUS_TARG_MEM_WADDR, addr);
-	wmb();
-	iwl_write_direct32(priv, HBUS_TARG_MEM_WDAT, val);
+	unsigned long reg_flags;
+
+	spin_lock_irqsave(&priv->reg_lock, reg_flags);
+	if (!iwl_grab_nic_access(priv)) {
+		_iwl_write_direct32(priv, HBUS_TARG_MEM_WADDR, addr);
+		wmb();
+		_iwl_write_direct32(priv, HBUS_TARG_MEM_WDAT, val);
+		iwl_release_nic_access(priv);
+	}
+	spin_unlock_irqrestore(&priv->reg_lock, reg_flags);
 }
 
 static inline void iwl_write_targ_mem_buf(struct iwl_priv *priv, u32 addr,
 					  u32 len, u32 *values)
 {
-	iwl_write_direct32(priv, HBUS_TARG_MEM_WADDR, addr);
-	wmb();
-	for (; 0 < len; len -= sizeof(u32), values++)
-		iwl_write_direct32(priv, HBUS_TARG_MEM_WDAT, *values);
+	unsigned long reg_flags;
+
+	spin_lock_irqsave(&priv->reg_lock, reg_flags);
+	if (!iwl_grab_nic_access(priv)) {
+		_iwl_write_direct32(priv, HBUS_TARG_MEM_WADDR, addr);
+		wmb();
+		for (; 0 < len; len -= sizeof(u32), values++)
+			_iwl_write_direct32(priv, HBUS_TARG_MEM_WDAT, *values);
+
+		iwl_release_nic_access(priv);
+	}
+	spin_unlock_irqrestore(&priv->reg_lock, reg_flags);
 }
 #endif