ptp: dp83640: don't define PAGE0

Building dp83640.c on arch/parisc/ produces a build warning for
PAGE0 being redefined. Since the macro is not used in the dp83640
driver, just make it a comment for documentation purposes.

In file included from ../drivers/net/phy/dp83640.c:23:
../drivers/net/phy/dp83640_reg.h:8: warning: "PAGE0" redefined
    8 | #define PAGE0                     0x0000
                 from ../drivers/net/phy/dp83640.c:11:
../arch/parisc/include/asm/page.h:187: note: this is the location of the previous definition
  187 | #define PAGE0   ((struct zeropage *)__PAGE_OFFSET)

Fixes: cb646e2b02b2 ("ptp: Added a clock driver for the National Semiconductor PHYTER.")
Signed-off-by: Randy Dunlap <>
Reported-by: Geert Uytterhoeven <>
Cc: Richard Cochran <>
Cc: John Stultz <>
Cc: Heiner Kallweit <>
Cc: Russell King <>
Reviewed-by: Andrew Lunn <>
Signed-off-by: Jakub Kicinski <>
diff --git a/drivers/net/phy/dp83640_reg.h b/drivers/net/phy/dp83640_reg.h
index 21aa24c..daae7fa 100644
--- a/drivers/net/phy/dp83640_reg.h
+++ b/drivers/net/phy/dp83640_reg.h
@@ -5,7 +5,7 @@
 #ifndef HAVE_DP83640_REGISTERS
 #define HAVE_DP83640_REGISTERS
-#define PAGE0                     0x0000
+/* #define PAGE0                  0x0000 */
 #define PHYCR2                    0x001c /* PHY Control Register 2 */
 #define PAGE4                     0x0004