xtensa: add alternative kernel memory layouts

MMUv3 is able to support low memory bigger than 128MB.
Implement 256MB and 512MB KSEG layouts:

- add Kconfig selector for KSEG layout;
- add KSEG base address, size and alignment definitions to
  arch/xtensa/include/asm/kmem_layout.h;
- use new definitions in TLB initialization;
- add build time memory map consistency checks.

See Documentation/xtensa/mmu.txt for the details of new memory layouts.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This commit is contained in:
Max Filippov
2016-04-11 21:14:17 +03:00
parent f1883aa7d6
commit d39af90265
9 changed files with 249 additions and 10 deletions

View File

@@ -116,22 +116,35 @@
add a5, a5, a4
bne a5, a2, 3b
/* Step 4: Setup MMU with the old V2 mappings. */
/* Step 4: Setup MMU with the requested static mappings. */
movi a6, 0x01000000
wsr a6, ITLBCFG
wsr a6, DTLBCFG
isync
movi a5, 0xd0000005
movi a4, CA_WRITEBACK
movi a5, XCHAL_KSEG_CACHED_VADDR + XCHAL_KSEG_TLB_WAY
movi a4, XCHAL_KSEG_PADDR + CA_WRITEBACK
wdtlb a4, a5
witlb a4, a5
movi a5, 0xd8000005
movi a4, CA_BYPASS
movi a5, XCHAL_KSEG_BYPASS_VADDR + XCHAL_KSEG_TLB_WAY
movi a4, XCHAL_KSEG_PADDR + CA_BYPASS
wdtlb a4, a5
witlb a4, a5
#ifdef CONFIG_XTENSA_KSEG_512M
movi a5, XCHAL_KSEG_CACHED_VADDR + 0x10000000 + XCHAL_KSEG_TLB_WAY
movi a4, XCHAL_KSEG_PADDR + 0x10000000 + CA_WRITEBACK
wdtlb a4, a5
witlb a4, a5
movi a5, XCHAL_KSEG_BYPASS_VADDR + 0x10000000 + XCHAL_KSEG_TLB_WAY
movi a4, XCHAL_KSEG_PADDR + 0x10000000 + CA_BYPASS
wdtlb a4, a5
witlb a4, a5
#endif
movi a5, XCHAL_KIO_CACHED_VADDR + 6
movi a4, XCHAL_KIO_DEFAULT_PADDR + CA_WRITEBACK
wdtlb a4, a5