macb: initial support for Cadence GEM

The Cadence GEM is based on the MACB Ethernet controller but has a few
small changes with regards to register and bitfield placement.  This
patch detects the presence of a GEM by reading the module ID register
and setting a flag appropriately.

This handles the new HW address, USRIO and hash register base register
locations in GEM.

v3: - convert to macb_is_gem() inline rather than storing a boolean
      flag
    - handle rx_overrun stats for gem

Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Tested-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>

1 files changed, 61 insertions, 0 deletions

diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
index d3212f6db703..d50057c244b2 100644
--- a/drivers/net/ethernet/cadence/macb.h
+++ b/drivers/net/ethernet/cadence/macb.h
@@ -59,6 +59,15 @@
 #define MACB_TPQ                                0x00bc
 #define MACB_USRIO                              0x00c0
 #define MACB_WOL                                0x00c4
+#define MACB_MID                                0x00fc
+
+/* GEM register offsets. */
+#define GEM_NCFGR                               0x0004
+#define GEM_USRIO                               0x000c
+#define GEM_HRB                                 0x0080
+#define GEM_HRT                                 0x0084
+#define GEM_SA1B                                0x0088
+#define GEM_SA1T                                0x008C
 
 /* Bitfields in NCR */
 #define MACB_LB_OFFSET                          0
@@ -228,6 +237,12 @@
 #define MACB_WOL_MTI_OFFSET                     19
 #define MACB_WOL_MTI_SIZE                       1
 
+/* Bitfields in MID */
+#define MACB_IDNUM_OFFSET                       16
+#define MACB_IDNUM_SIZE                         16
+#define MACB_REV_OFFSET                         0
+#define MACB_REV_SIZE                           16
+
 /* Constants for CLK */
 #define MACB_CLK_DIV8                           0
 #define MACB_CLK_DIV16                          1
@@ -254,11 +269,52 @@
                     << MACB_##name##_OFFSET))           \
          | MACB_BF(name,value))
 
+#define GEM_BIT(name)                                   \
+        (1 << GEM_##name##_OFFSET)
+#define GEM_BF(name, value)                             \
+        (((value) & ((1 << GEM_##name##_SIZE) - 1))     \
+         << GEM_##name##_OFFSET)
+#define GEM_BFEXT(name, value)\
+        (((value) >> GEM_##name##_OFFSET)               \
+         & ((1 << GEM_##name##_SIZE) - 1))
+#define GEM_BFINS(name, value, old)                     \
+        (((old) & ~(((1 << GEM_##name##_SIZE) - 1)      \
+                    << GEM_##name##_OFFSET))            \
+         | GEM_BF(name, value))
+
 /* Register access macros */
 #define macb_readl(port,reg)                            \
         __raw_readl((port)->regs + MACB_##reg)
 #define macb_writel(port,reg,value)                     \
         __raw_writel((value), (port)->regs + MACB_##reg)
+#define gem_readl(port, reg)                            \
+        __raw_readl((port)->regs + GEM_##reg)
+#define gem_writel(port, reg, value)                    \
+        __raw_writel((value), (port)->regs + GEM_##reg)
+
+/*
+ * Conditional GEM/MACB macros.  These perform the operation to the correct
+ * register dependent on whether the device is a GEM or a MACB.  For registers
+ * and bitfields that are common across both devices, use macb_{read,write}l
+ * to avoid the cost of the conditional.
+ */
+#define macb_or_gem_writel(__bp, __reg, __value) \
+        ({ \
+                if (macb_is_gem((__bp))) \
+                        gem_writel((__bp), __reg, __value); \
+                else \
+                        macb_writel((__bp), __reg, __value); \
+        })
+
+#define macb_or_gem_readl(__bp, __reg) \
+        ({ \
+                u32 __v; \
+                if (macb_is_gem((__bp))) \
+                        __v = gem_readl((__bp), __reg); \
+                else \
+                        __v = macb_readl((__bp), __reg); \
+                __v; \
+        })
 
 struct dma_desc {
         u32     addr;
@@ -391,4 +447,9 @@ struct macb {
         unsigned int            duplex;
 };
 
+static inline bool macb_is_gem(struct macb *bp)
+{
+        return MACB_BFEXT(IDNUM, macb_readl(bp, MID)) == 0x2;
+}
+
 #endif /* _MACB_H */