bnx2x: Don't pretend during register dump

As part of a register dump, the interface pretends to have the identity
of other interfaces of the same physical device in order to perform
HW configuration for them - specifically, it needs to prevent attentions
from generating on those functions as the register dump accesses registers
in common blocks which whose reading might generate an attention.

However, such pretension is unsafe - unlike other flows in which the driver
uses pretend, during register dump there is no guarantee no other HW access
will take place (by other flows). If such access will take place, the HW will
be accessed by the wrong interface, and leave both functions in an incorrect
state.

This patch removes all pretensions from the register dump flow. Instead, it
changes initial configuration of attentions such that no fatal attention will
be generated for other functions as a result of the register dump
(notice however, a debug print claiming an attention from other functions IS
possible during the register dump)
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Ariel Elior <ariele@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c

@@ -891,17 +891,8 @@ static void bnx2x_get_regs(struct net_device *dev,
 	 * will re-enable parity attentions right after the dump.
 	 */
 
-	/* Disable parity on path 0 */
-	bnx2x_pretend_func(bp, 0);
 	bnx2x_disable_blocks_parity(bp);
 
-	/* Disable parity on path 1 */
-	bnx2x_pretend_func(bp, 1);
-	bnx2x_disable_blocks_parity(bp);
-
-	/* Return to current function */
-	bnx2x_pretend_func(bp, BP_ABS_FUNC(bp));
-
 	dump_hdr.header_size = (sizeof(struct dump_header) / 4) - 1;
 	dump_hdr.preset = DUMP_ALL_PRESETS;
 	dump_hdr.version = BNX2X_DUMP_VERSION;
@@ -928,18 +919,9 @@ static void bnx2x_get_regs(struct net_device *dev,
 	/* Actually read the registers */
 	__bnx2x_get_regs(bp, p);
 
-	/* Re-enable parity attentions on path 0 */
-	bnx2x_pretend_func(bp, 0);
+	/* Re-enable parity attentions */
 	bnx2x_clear_blocks_parity(bp);
 	bnx2x_enable_blocks_parity(bp);
-
-	/* Re-enable parity attentions on path 1 */
-	bnx2x_pretend_func(bp, 1);
-	bnx2x_clear_blocks_parity(bp);
-	bnx2x_enable_blocks_parity(bp);
-
-	/* Return to current function */
-	bnx2x_pretend_func(bp, BP_ABS_FUNC(bp));
 }
 
 static int bnx2x_get_preset_regs_len(struct net_device *dev, u32 preset)
@@ -993,17 +975,8 @@ static int bnx2x_get_dump_data(struct net_device *dev,
 	 * will re-enable parity attentions right after the dump.
 	 */
 
-	/* Disable parity on path 0 */
-	bnx2x_pretend_func(bp, 0);
 	bnx2x_disable_blocks_parity(bp);
 
-	/* Disable parity on path 1 */
-	bnx2x_pretend_func(bp, 1);
-	bnx2x_disable_blocks_parity(bp);
-
-	/* Return to current function */
-	bnx2x_pretend_func(bp, BP_ABS_FUNC(bp));
-
 	dump_hdr.header_size = (sizeof(struct dump_header) / 4) - 1;
 	dump_hdr.preset = bp->dump_preset_idx;
 	dump_hdr.version = BNX2X_DUMP_VERSION;
@@ -1032,19 +1005,10 @@ static int bnx2x_get_dump_data(struct net_device *dev,
 	/* Actually read the registers */
 	__bnx2x_get_preset_regs(bp, p, dump_hdr.preset);
 
-	/* Re-enable parity attentions on path 0 */
-	bnx2x_pretend_func(bp, 0);
+	/* Re-enable parity attentions */
 	bnx2x_clear_blocks_parity(bp);
 	bnx2x_enable_blocks_parity(bp);
 
-	/* Re-enable parity attentions on path 1 */
-	bnx2x_pretend_func(bp, 1);
-	bnx2x_clear_blocks_parity(bp);
-	bnx2x_enable_blocks_parity(bp);
-
-	/* Return to current function */
-	bnx2x_pretend_func(bp, BP_ABS_FUNC(bp));
-
 	return 0;
 }
 

drivers/net/ethernet/broadcom/bnx2x/bnx2x_init.h

@@ -640,23 +640,35 @@ static const struct {
  * [30] MCP Latched ump_tx_parity
  * [31] MCP Latched scpad_parity
  */
-#define MISC_AEU_ENABLE_MCP_PRTY_BITS	\
+#define MISC_AEU_ENABLE_MCP_PRTY_SUB_BITS	\
 	(AEU_INPUTS_ATTN_BITS_MCP_LATCHED_ROM_PARITY | \
 	 AEU_INPUTS_ATTN_BITS_MCP_LATCHED_UMP_RX_PARITY | \
-	 AEU_INPUTS_ATTN_BITS_MCP_LATCHED_UMP_TX_PARITY | \
+	 AEU_INPUTS_ATTN_BITS_MCP_LATCHED_UMP_TX_PARITY)
+
+#define MISC_AEU_ENABLE_MCP_PRTY_BITS	\
+	(MISC_AEU_ENABLE_MCP_PRTY_SUB_BITS | \
 	 AEU_INPUTS_ATTN_BITS_MCP_LATCHED_SCPAD_PARITY)
 
 /* Below registers control the MCP parity attention output. When
  * MISC_AEU_ENABLE_MCP_PRTY_BITS are set - attentions are
  * enabled, when cleared - disabled.
  */
-static const u32 mcp_attn_ctl_regs[] = {
-	MISC_REG_AEU_ENABLE4_FUNC_0_OUT_0,
-	MISC_REG_AEU_ENABLE4_NIG_0,
-	MISC_REG_AEU_ENABLE4_PXP_0,
-	MISC_REG_AEU_ENABLE4_FUNC_1_OUT_0,
-	MISC_REG_AEU_ENABLE4_NIG_1,
-	MISC_REG_AEU_ENABLE4_PXP_1
+static const struct {
+	u32 addr;
+	u32 bits;
+} mcp_attn_ctl_regs[] = {
+	{ MISC_REG_AEU_ENABLE4_FUNC_0_OUT_0,
+		MISC_AEU_ENABLE_MCP_PRTY_BITS },
+	{ MISC_REG_AEU_ENABLE4_NIG_0,
+		MISC_AEU_ENABLE_MCP_PRTY_SUB_BITS },
+	{ MISC_REG_AEU_ENABLE4_PXP_0,
+		MISC_AEU_ENABLE_MCP_PRTY_SUB_BITS },
+	{ MISC_REG_AEU_ENABLE4_FUNC_1_OUT_0,
+		MISC_AEU_ENABLE_MCP_PRTY_BITS },
+	{ MISC_REG_AEU_ENABLE4_NIG_1,
+		MISC_AEU_ENABLE_MCP_PRTY_SUB_BITS },
+	{ MISC_REG_AEU_ENABLE4_PXP_1,
+		MISC_AEU_ENABLE_MCP_PRTY_SUB_BITS }
 };
 
 static inline void bnx2x_set_mcp_parity(struct bnx2x *bp, u8 enable)
@@ -665,14 +677,14 @@ static inline void bnx2x_set_mcp_parity(struct bnx2x *bp, u8 enable)
 	u32 reg_val;
 
 	for (i = 0; i < ARRAY_SIZE(mcp_attn_ctl_regs); i++) {
-		reg_val = REG_RD(bp, mcp_attn_ctl_regs[i]);
+		reg_val = REG_RD(bp, mcp_attn_ctl_regs[i].addr);
 
 		if (enable)
-			reg_val |= MISC_AEU_ENABLE_MCP_PRTY_BITS;
+			reg_val |= mcp_attn_ctl_regs[i].bits;
 		else
-			reg_val &= ~MISC_AEU_ENABLE_MCP_PRTY_BITS;
+			reg_val &= ~mcp_attn_ctl_regs[i].bits;
 
-		REG_WR(bp, mcp_attn_ctl_regs[i], reg_val);
+		REG_WR(bp, mcp_attn_ctl_regs[i].addr, reg_val);
 	}
 }