ARMv7: Document the PRRR and NMRR registers setting

This patch adds a comment to the proc-v7.S file for the setting of the
PRRR and NMRR registers. It also sets the PRRR[13:12] bits to 0
(corresponding to the reserved TEX[0]CB encoding 110) to be consistent
with the documentation.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Catalin Marinas 2009-05-30 14:00:16 +01:00
parent 213fb2a8ee
commit 23d1c515d8

View File

@ -219,8 +219,36 @@ __v7_setup:
mov r10, #0x1f @ domains 0, 1 = manager
mcr p15, 0, r10, c3, c0, 0 @ load domain access register
#endif
ldr r5, =0xff0aa1a8
ldr r6, =0x40e040e0
/*
* Memory region attributes with SCTLR.TRE=1
*
* n = TEX[0],C,B
* TR = PRRR[2n+1:2n] - memory type
* IR = NMRR[2n+1:2n] - inner cacheable property
* OR = NMRR[2n+17:2n+16] - outer cacheable property
*
* n TR IR OR
* UNCACHED 000 00
* BUFFERABLE 001 10 00 00
* WRITETHROUGH 010 10 10 10
* WRITEBACK 011 10 11 11
* reserved 110
* WRITEALLOC 111 10 01 01
* DEV_SHARED 100 01
* DEV_NONSHARED 100 01
* DEV_WC 001 10
* DEV_CACHED 011 10
*
* Other attributes:
*
* DS0 = PRRR[16] = 0 - device shareable property
* DS1 = PRRR[17] = 1 - device shareable property
* NS0 = PRRR[18] = 0 - normal shareable property
* NS1 = PRRR[19] = 1 - normal shareable property
* NOS = PRRR[24+n] = 1 - not outer shareable
*/
ldr r5, =0xff0a81a8 @ PRRR
ldr r6, =0x40e040e0 @ NMRR
mcr p15, 0, r5, c10, c2, 0 @ write PRRR
mcr p15, 0, r6, c10, c2, 1 @ write NMRR
adr r5, v7_crval