If one custom board is using the 8MB flash, it is set as FLASH_BASE = 0xef000000, TEXT_BASE = 0xef780000. The current start.S code will be broken at switch_as.
It is because the TLB1[15] is set as 16MB page size, EPN = TEXT_BASE & 0xff000000, RPN = 0xff000000.
For the 8MB flash case, the EPN = 0xefxxxxxx, RPN = 0xffxxxxxx. Assume the virt address of switch_as is 0xef7ff18c, the real address of the instruction at switch_as should be 0xff7ff18c. the 0xff7ff18c is out of the range of the default 8MB boot LAW window 0xff800000 - 0xffffffff.
So when we switch to AS1 address space at switch_as, the core can't fetch the instruction at switch_as any more. It will cause broken issue.
Signed-off-by: Dave Liu daveliu@freescale.com --- cpu/mpc85xx/start.S | 16 ++++++++-------- 1 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/cpu/mpc85xx/start.S b/cpu/mpc85xx/start.S index 8fa0ff7..80f9677 100644 --- a/cpu/mpc85xx/start.S +++ b/cpu/mpc85xx/start.S @@ -184,19 +184,19 @@ _start_e500: mtspr DBCR0,r0 #endif
- /* create a temp mapping in AS=1 to the boot window */ + /* create a temp mapping in AS=1 to the 4M boot window */ lis r6,FSL_BOOKE_MAS0(1, 15, 0)@h ori r6,r6,FSL_BOOKE_MAS0(1, 15, 0)@l
- lis r7,FSL_BOOKE_MAS1(1, 1, 0, 1, BOOKE_PAGESZ_16M)@h - ori r7,r7,FSL_BOOKE_MAS1(1, 1, 0, 1, BOOKE_PAGESZ_16M)@l + lis r7,FSL_BOOKE_MAS1(1, 1, 0, 1, BOOKE_PAGESZ_4M)@h + ori r7,r7,FSL_BOOKE_MAS1(1, 1, 0, 1, BOOKE_PAGESZ_4M)@l
- /* Align the mapping to 16MB */ - lis r8,FSL_BOOKE_MAS2(TEXT_BASE & 0xff000000, (MAS2_I|MAS2_G))@h - ori r8,r8,FSL_BOOKE_MAS2(TEXT_BASE & 0xff000000, (MAS2_I|MAS2_G))@l + lis r8,FSL_BOOKE_MAS2(TEXT_BASE & 0xffc00000, (MAS2_I|MAS2_G))@h + ori r8,r8,FSL_BOOKE_MAS2(TEXT_BASE & 0xffc00000, (MAS2_I|MAS2_G))@l
- lis r9,FSL_BOOKE_MAS3(0xff000000, 0, (MAS3_SX|MAS3_SW|MAS3_SR))@h - ori r9,r9,FSL_BOOKE_MAS3(0xff000000, 0, (MAS3_SX|MAS3_SW|MAS3_SR))@l + /* The 85xx has the default boot window 0xff800000 - 0xffffffff */ + lis r9,FSL_BOOKE_MAS3(0xffc00000, 0, (MAS3_SX|MAS3_SW|MAS3_SR))@h + ori r9,r9,FSL_BOOKE_MAS3(0xffc00000, 0, (MAS3_SX|MAS3_SW|MAS3_SR))@l
mtspr MAS0,r6 mtspr MAS1,r7