[RFC Patch 06/12] IXGBEVF: Add self emulation layer

[Lan Tianyu <tianyu.lan@intel.com>]

In order to restore VF function after migration, add self emulation layer
to record regs' values during accessing regs.

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
---
 drivers/net/ethernet/intel/ixgbevf/Makefile        |  3 ++-
 drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c  |  2 +-
 .../net/ethernet/intel/ixgbevf/self-emulation.c    | 26 ++++++++++++++++++++++
 drivers/net/ethernet/intel/ixgbevf/vf.h            |  5 ++++-
 4 files changed, 33 insertions(+), 3 deletions(-)
 create mode 100644 drivers/net/ethernet/intel/ixgbevf/self-emulation.c

diff --git a/drivers/net/ethernet/intel/ixgbevf/Makefile b/drivers/net/ethernet/intel/ixgbevf/Makefile
index 4ce4c97..841c884 100644
--- a/drivers/net/ethernet/intel/ixgbevf/Makefile
+++ b/drivers/net/ethernet/intel/ixgbevf/Makefile
@@ -31,7 +31,8 @@
 
 obj-$(CONFIG_IXGBEVF) += ixgbevf.o
 
-ixgbevf-objs := vf.o \
+ixgbevf-objs := self-emulation.o \
+		vf.o \
                 mbx.o \
                 ethtool.o \
                 ixgbevf_main.o
diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
index a16d267..4446916 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
+++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
@@ -156,7 +156,7 @@ u32 ixgbevf_read_reg(struct ixgbe_hw *hw, u32 reg)
 
 	if (IXGBE_REMOVED(reg_addr))
 		return IXGBE_FAILED_READ_REG;
-	value = readl(reg_addr + reg);
+	value = ixgbe_self_emul_readl(reg_addr, reg);
 	if (unlikely(value == IXGBE_FAILED_READ_REG))
 		ixgbevf_check_remove(hw, reg);
 	return value;
diff --git a/drivers/net/ethernet/intel/ixgbevf/self-emulation.c b/drivers/net/ethernet/intel/ixgbevf/self-emulation.c
new file mode 100644
index 0000000..d74b2da
--- /dev/null
+++ b/drivers/net/ethernet/intel/ixgbevf/self-emulation.c
@@ -0,0 +1,26 @@
+#include <linux/netdevice.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <net/arp.h>
+
+#include "vf.h"
+#include "ixgbevf.h"
+
+static u32 hw_regs[0x4000];
+
+u32 ixgbe_self_emul_readl(volatile void __iomem *base, u32 addr)
+{
+	u32 tmp;
+
+	tmp = readl(base + addr);
+	hw_regs[(unsigned long)addr] = tmp;
+
+	return tmp;
+}
+
+void ixgbe_self_emul_writel(u32 val, volatile void __iomem *base, u32  addr)
+{
+	hw_regs[(unsigned long)addr] = val;
+	writel(val, (volatile void __iomem *)(base + addr));
+}
diff --git a/drivers/net/ethernet/intel/ixgbevf/vf.h b/drivers/net/ethernet/intel/ixgbevf/vf.h
index d40f036..6a3f4eb 100644
--- a/drivers/net/ethernet/intel/ixgbevf/vf.h
+++ b/drivers/net/ethernet/intel/ixgbevf/vf.h
@@ -39,6 +39,9 @@
 
 struct ixgbe_hw;
 
+u32 ixgbe_self_emul_readl(volatile void __iomem *base, u32 addr);
+void ixgbe_self_emul_writel(u32 val, volatile void __iomem *base, u32  addr);
+
 /* iterator type for walking multicast address lists */
 typedef u8* (*ixgbe_mc_addr_itr) (struct ixgbe_hw *hw, u8 **mc_addr_ptr,
 				  u32 *vmdq);
@@ -182,7 +185,7 @@ static inline void ixgbe_write_reg(struct ixgbe_hw *hw, u32 reg, u32 value)
 
 	if (IXGBE_REMOVED(reg_addr))
 		return;
-	writel(value, reg_addr + reg);
+	ixgbe_self_emul_writel(value, reg_addr, reg);
 }
 
 #define IXGBE_WRITE_REG(h, r, v) ixgbe_write_reg(h, r, v)
-- 
1.8.4.rc0.1.g8f6a3e5.dirty