[U-Boot] more "#if 0" pedantry related to moving macros in header files

[Robert P. J. Day]

  my apologies for yet more pedantic nitpickery, this time related to
how to properly move/locate macro definitions in header files. i
notice this bit in include/mpc8xx.h (note the two tests of "#if 0"):

/*-----------------------------------------------------------------------
 * TBSCR - Time Base Status and Control Register                        11-26
 */
#define TBSCR_TBIRQ7    0x8000          /* Time Base Interrupt Request 7        */
#define TBSCR_TBIRQ6    0x4000          /* Time Base Interrupt Request 6        */
#define TBSCR_TBIRQ5    0x2000          /* Time Base Interrupt Request 5        */
#define TBSCR_TBIRQ4    0x1000          /* Time Base Interrupt Request 4        */
#define TBSCR_TBIRQ3    0x0800          /* Time Base Interrupt Request 3        */
#define TBSCR_TBIRQ2    0x0400          /* Time Base Interrupt Request 2        */
#define TBSCR_TBIRQ1    0x0200          /* Time Base Interrupt Request 1        */
#define TBSCR_TBIRQ0    0x0100          /* Time Base Interrupt Request 0        */
#if 0   /* already in asm/8xx_immap.h */
#define TBSCR_REFA      0x0080          /* Reference Interrupt Status A         */
#define TBSCR_REFB      0x0040          /* Reference Interrupt Status B         */
#define TBSCR_REFAE     0x0008          /* Second Interrupt Enable A            */
#define TBSCR_REFBE     0x0004          /* Second Interrupt Enable B            */
#define TBSCR_TBF       0x0002          /* Time Base Freeze                     */
#define TBSCR_TBE       0x0001          /* Time Base Enable                     */
#endif

/*-----------------------------------------------------------------------
 * PISCR - Periodic Interrupt Status and Control Register               11-31
 */
#undef  PISCR_PIRQ                      /* TBD                                  */
#define PISCR_PITF      0x0002          /* Periodic Interrupt Timer Freeze      */
#if 0   /* already in asm/8xx_immap.h */
#define PISCR_PS        0x0080          /* Periodic interrupt Status            */
#define PISCR_PIE       0x0004          /* Periodic Interrupt Enable            */
#define PISCR_PTE       0x0001          /* Periodic Timer Enable                */
#endif

  sure enough, the parts that are "if 0"ed out are indeed in
arch/powerpc/include/asm/8xx_immap.h:

#define TBSCR_TBIRQ_MASK        ((ushort)0xff00)
#define TBSCR_REFA              ((ushort)0x0080)
#define TBSCR_REFB              ((ushort)0x0040)
#define TBSCR_REFAE             ((ushort)0x0008)
#define TBSCR_REFBE             ((ushort)0x0004)
#define TBSCR_TBF               ((ushort)0x0002)
#define TBSCR_TBE               ((ushort)0x0001)

... snip ...

#define PISCR_PIRQ_MASK         ((ushort)0xff00)
#define PISCR_PS                ((ushort)0x0080)
#define PISCR_PIE               ((ushort)0x0004)
#define PISCR_PTF               ((ushort)0x0002)
#define PISCR_PTE               ((ushort)0x0001)

  but this brings up the question, where should content like that
properly be defined? it seems awkward to break the bit flag
definitions for a single register over two header files (especially
when they're not defined syntactically identically). is there a
historical reason that that content is split over two header files?

  oh, and about the above, there is only one reference in the entire
tree to PISCR_PIRQ (where it's being undef'ed):

  include/mpc8xx.h:#undef	PISCR_PIRQ			/* TBD	*/

so i'm guessing that's superfluous (perhaps the old form for defining
PISCR_PIRQ_MASK?). i'd submit a patch to get rid of it, but i'll hold
off if i can do a larger cleanup that covers that as well in one shot.

  thoughts?

rday

p.s.  hang on ... this bit in arch/powerpc/include/asm/8xx_immap.h:

#define TBSCR_TBIRQ_MASK        ((ushort)0xff00)
#define TBSCR_REFA              ((ushort)0x0080)
#define TBSCR_REFB              ((ushort)0x0040)
#define TBSCR_REFAE             ((ushort)0x0008)
#define TBSCR_REFBE             ((ushort)0x0004)
#define TBSCR_TBF               ((ushort)0x0002)
#define TBSCR_TBE               ((ushort)0x0001)

#define RTCSC_RTCIRQ_MASK       ((ushort)0xff00)
#define RTCSC_SEC               ((ushort)0x0080)
#define RTCSC_ALR               ((ushort)0x0040)
#define RTCSC_38K               ((ushort)0x0010)
#define RTCSC_SIE               ((ushort)0x0008)
#define RTCSC_ALE               ((ushort)0x0004)
#define RTCSC_RTF               ((ushort)0x0002)
#define RTCSC_RTE               ((ushort)0x0001)

#define PISCR_PIRQ_MASK         ((ushort)0xff00)
#define PISCR_PS                ((ushort)0x0080)
#define PISCR_PIE               ((ushort)0x0004)
#define PISCR_PTF               ((ushort)0x0002)
#define PISCR_PTE               ((ushort)0x0001)

  i just noticed that none of the *_MASK macros are referenced
anywhere in the entire source tree:

$ grep -r TBSCR_TBIRQ_MASK *
arch/powerpc/include/asm/8xx_immap.h:#define TBSCR_TBIRQ_MASK	((ushort)0xff00)
$ grep -r RTCSC_RTCIRQ_MASK *
arch/powerpc/include/asm/8xx_immap.h:#define RTCSC_RTCIRQ_MASK	((ushort)0xff00)
$ grep -r PISCR_PIRQ_MASK *
arch/powerpc/include/asm/8xx_immap.h:#define PISCR_PIRQ_MASK		((ushort)0xff00)
arch/powerpc/include/asm/immap_8260.h:#define PISCR_PIRQ_MASK		((ushort)0xff00)
$

so what are they used for?

-- 

========================================================================
Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
========================================================================