diff options
Diffstat (limited to 'arch/blackfin/mach-common')
| -rw-r--r-- | arch/blackfin/mach-common/cplbmgr.S | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/arch/blackfin/mach-common/cplbmgr.S b/arch/blackfin/mach-common/cplbmgr.S index 6f909cbfac7..faca1ab344d 100644 --- a/arch/blackfin/mach-common/cplbmgr.S +++ b/arch/blackfin/mach-common/cplbmgr.S @@ -75,6 +75,15 @@ ENTRY(_cplb_mgr) * from the configuration table. */ + /* A multi-word instruction can cross a page boundary. This means the + * first part of the instruction can be in a valid page, but the + * second part is not, and hence generates the instruction miss. + * However, the fault address is for the start of the instruction, + * not the part that's in the bad page. Therefore, we have to check + * whether the fault address applies to a page that is already present + * in the table. + */ + P4.L = LO(ICPLB_FAULT_ADDR); P4.H = HI(ICPLB_FAULT_ADDR); @@ -87,7 +96,7 @@ ENTRY(_cplb_mgr) R4 = [P4]; /* Get faulting address*/ R6 = 64; /* Advance past the fault address, which*/ R6 = R6 + R4; /* we'll use if we find a match*/ - R3 = ((16 << 8) | 2); /* Extract mask, bits 16 and 17.*/ + R3 = ((16 << 8) | 2); /* Extract mask, two bits at posn 16 */ R5 = 0; .Lisearch: @@ -125,7 +134,9 @@ ENTRY(_cplb_mgr) P4.L = LO(IMEM_CONTROL); P4.H = HI(IMEM_CONTROL); - /* disable cplbs */ + /* Turn off CPLBs while we work, necessary according to HRM before + * modifying CPLB descriptors + */ R5 = [P4]; /* Control Register*/ BITCLR(R5,ENICPLB_P); CLI R1; |