ARM assembler macro question

Hi,

Simple question, but very hard to find answer, maybe somebody here knows:

I want to create a simple macro like I can in C:

#define ALIGN_UP(addr, align)   (((addr) + (align) - 1) & ~((align) - 1))

I've tried:

MACRO
ALIGN_UP $addr,$align
((($addr) + ($align) - 1) & ~(($align) - 1))
MEND

but this doesn't work:

MYVAR    EQU    ALIGN_UP(768, 1024)

I get "error A2173: syntax error in expression".

I've also tried:

MACRO
ALIGN_UP $var,$addr,$align
$var EQU ((($addr) + ($align) - 1) & ~(($align) - 1))
MEND

But this also doesn't work:

ALIGN_UP(MYVAR, 768, 1024)

I get "error A2007: wrong operand type for  '-'"

In the examples above I use numbers, but of course what I want to accomplish is like this:

IMAGE_BOOT_BOOTIMAGE_START_OFFSET   EQU    ALIGN_UP(IMAGE_BOOT_BOOTIMAGE_CSF_OFFSET+IMAGE_BOOT_BOOTIMAGE_CSF_SIZE, 1024)

This of course works just fine:

IMAGE_BOOT_BOOTIMAGE_START_OFFSET   EQU     (((IMAGE_BOOT_BOOTIMAGE_CSF_OFFSET+IMAGE_BOOT_BOOTIMAGE_CSF_SIZE) + (1024 - 1)) & ~(1024 - 1))

But it's a maintenance nightmare.

Surely using macros like this must be possible in ARM assembly?