xlat_tables_v2: use get_current_el_maybe_constant() in is_dcache_enabled()
Using get_current_el_maybe_constant() produces more optimized code
because in most cases, we know the exception level at build-time.
For example, BL31 runs at EL3, so unneeded code will be trimmed.
[before]
0000000000000000 <is_dcache_enabled>:
0: d5384240 mrs x0, currentel
4: 53020c00 ubfx w0, w0, #2, #2
8: 7100041f cmp w0, #0x1
c: 54000081 b.ne 1c <is_dcache_enabled+0x1c> // b.any
10: d5381000 mrs x0, sctlr_el1
14: 53020800 ubfx w0, w0, #2, #1
18: d65f03c0 ret
1c: 7100081f cmp w0, #0x2
20: 54000061 b.ne 2c <is_dcache_enabled+0x2c> // b.any
24: d53c1000 mrs x0, sctlr_el2
28: 17fffffb b 14 <is_dcache_enabled+0x14>
2c: d53e1000 mrs x0, sctlr_el3
30: 17fffff9 b 14 <is_dcache_enabled+0x14>
[after]
0000000000000000 <is_dcache_enabled>:
0: d53e1000 mrs x0, sctlr_el3
4: 53020800 ubfx w0, w0, #2, #1
8: d65f03c0 ret
Change-Id: I3698fae9b517022ff9fbfd4cad3a320c6e137e10
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
3cde15fade