/*
- * Copyright (c) 2010, 2012-2013 ARM Limited
+ * Copyright (c) 2010, 2012-2014 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
case EL0:
case EL1:
currState->sctlr = currState->tc->readMiscReg(MISCREG_SCTLR_EL1);
- currState->ttbcr = currState->tc->readMiscReg(MISCREG_TCR_EL1);
+ currState->tcr = currState->tc->readMiscReg(MISCREG_TCR_EL1);
break;
// @todo: uncomment this to enable Virtualization
// case EL2:
// assert(haveVirtualization);
// currState->sctlr = currState->tc->readMiscReg(MISCREG_SCTLR_EL2);
- // currState->ttbcr = currState->tc->readMiscReg(MISCREG_TCR_EL2);
+ // currState->tcr = currState->tc->readMiscReg(MISCREG_TCR_EL2);
// break;
case EL3:
assert(haveSecurity);
currState->sctlr = currState->tc->readMiscReg(MISCREG_SCTLR_EL3);
- currState->ttbcr = currState->tc->readMiscReg(MISCREG_TCR_EL3);
+ currState->tcr = currState->tc->readMiscReg(MISCREG_TCR_EL3);
break;
default:
panic("Invalid exception level");
currState->longDesc.lookupLevel = start_lookup_level;
currState->longDesc.aarch64 = false;
- currState->longDesc.largeGrain = false;
- currState->longDesc.grainSize = 12;
+ currState->longDesc.grainSize = Grain4KB;
Event *event = start_lookup_level == L1 ? (Event *) &doL1LongDescEvent
: (Event *) &doL2LongDescEvent;
{
assert(currState->aarch64);
- DPRINTF(TLB, "Beginning table walk for address %#llx, TTBCR: %#llx\n",
- currState->vaddr_tainted, currState->ttbcr);
+ DPRINTF(TLB, "Beginning table walk for address %#llx, TCR: %#llx\n",
+ currState->vaddr_tainted, currState->tcr);
+
+ static const GrainSize GrainMapDefault[] =
+ { Grain4KB, Grain64KB, Grain16KB, ReservedGrain };
+ static const GrainSize GrainMap_EL1_tg1[] =
+ { ReservedGrain, Grain16KB, Grain4KB, Grain64KB };
// Determine TTBR, table size, granule size and phys. address range
Addr ttbr = 0;
int tsz = 0, ps = 0;
- bool large_grain = false;
+ GrainSize tg = Grain4KB; // grain size computed from tg* field
bool fault = false;
switch (currState->el) {
case EL0:
case 0:
DPRINTF(TLB, " - Selecting TTBR0 (AArch64)\n");
ttbr = currState->tc->readMiscReg(MISCREG_TTBR0_EL1);
- tsz = adjustTableSizeAArch64(64 - currState->ttbcr.t0sz);
- large_grain = currState->ttbcr.tg0;
+ tsz = adjustTableSizeAArch64(64 - currState->tcr.t0sz);
+ tg = GrainMapDefault[currState->tcr.tg0];
if (bits(currState->vaddr, 63, tsz) != 0x0 ||
- currState->ttbcr.epd0)
+ currState->tcr.epd0)
fault = true;
break;
case 0xffff:
DPRINTF(TLB, " - Selecting TTBR1 (AArch64)\n");
ttbr = currState->tc->readMiscReg(MISCREG_TTBR1_EL1);
- tsz = adjustTableSizeAArch64(64 - currState->ttbcr.t1sz);
- large_grain = currState->ttbcr.tg1;
+ tsz = adjustTableSizeAArch64(64 - currState->tcr.t1sz);
+ tg = GrainMap_EL1_tg1[currState->tcr.tg1];
if (bits(currState->vaddr, 63, tsz) != mask(64-tsz) ||
- currState->ttbcr.epd1)
+ currState->tcr.epd1)
fault = true;
break;
default:
// top two bytes must be all 0s or all 1s, else invalid addr
fault = true;
}
- ps = currState->ttbcr.ips;
+ ps = currState->tcr.ips;
break;
case EL2:
case EL3:
switch(bits(currState->vaddr, 63,48)) {
case 0:
- DPRINTF(TLB, " - Selecting TTBR0 (AArch64)\n");
- if (currState->el == EL2)
- ttbr = currState->tc->readMiscReg(MISCREG_TTBR0_EL2);
- else
- ttbr = currState->tc->readMiscReg(MISCREG_TTBR0_EL3);
- tsz = adjustTableSizeAArch64(64 - currState->ttbcr.t0sz);
- large_grain = currState->ttbcr.tg0;
+ DPRINTF(TLB, " - Selecting TTBR0 (AArch64)\n");
+ if (currState->el == EL2)
+ ttbr = currState->tc->readMiscReg(MISCREG_TTBR0_EL2);
+ else
+ ttbr = currState->tc->readMiscReg(MISCREG_TTBR0_EL3);
+ tsz = adjustTableSizeAArch64(64 - currState->tcr.t0sz);
+ tg = GrainMapDefault[currState->tcr.tg0];
break;
default:
// invalid addr if top two bytes are not all 0s
- fault = true;
+ fault = true;
}
- ps = currState->ttbcr.ps;
+ ps = currState->tcr.ips;
break;
}
}
+ if (tg == ReservedGrain) {
+ warn_once("Reserved granule size requested; gem5's IMPLEMENTATION "
+ "DEFINED behavior takes this to mean 4KB granules\n");
+ tg = Grain4KB;
+ }
+
+ int stride = tg - 3;
+ LookupLevel start_lookup_level = MAX_LOOKUP_LEVELS;
+
// Determine starting lookup level
- LookupLevel start_lookup_level;
- int grain_size, stride;
- if (large_grain) { // 64 KB granule
- grain_size = 16;
- stride = grain_size - 3;
- if (tsz > grain_size + 2 * stride)
- start_lookup_level = L1;
- else if (tsz > grain_size + stride)
- start_lookup_level = L2;
- else
- start_lookup_level = L3;
- } else { // 4 KB granule
- grain_size = 12;
- stride = grain_size - 3;
- if (tsz > grain_size + 3 * stride)
- start_lookup_level = L0;
- else if (tsz > grain_size + 2 * stride)
- start_lookup_level = L1;
- else
- start_lookup_level = L2;
+ // See aarch64/translation/walk in Appendix G: ARMv8 Pseudocode Library
+ // in ARM DDI 0487A. These table values correspond to the cascading tests
+ // to compute the lookup level and are of the form
+ // (grain_size + N*stride), for N = {1, 2, 3}.
+ // A value of 64 will never succeed and a value of 0 will always succeed.
+ {
+ struct GrainMap {
+ GrainSize grain_size;
+ unsigned lookup_level_cutoff[MAX_LOOKUP_LEVELS];
+ };
+ static const GrainMap GM[] = {
+ { Grain4KB, { 39, 30, 0, 0 } },
+ { Grain16KB, { 47, 36, 25, 0 } },
+ { Grain64KB, { 64, 42, 29, 0 } }
+ };
+
+ const unsigned *lookup = NULL; // points to a lookup_level_cutoff
+
+ for (unsigned i = 0; i < 3; ++i) { // choose entry of GM[]
+ if (tg == GM[i].grain_size) {
+ lookup = GM[i].lookup_level_cutoff;
+ break;
+ }
+ }
+ assert(lookup);
+
+ for (int L = L0; L != MAX_LOOKUP_LEVELS; ++L) {
+ if (tsz > lookup[L]) {
+ start_lookup_level = (LookupLevel) L;
+ break;
+ }
+ }
+ panic_if(start_lookup_level == MAX_LOOKUP_LEVELS,
+ "Table walker couldn't find lookup level\n");
}
// Determine table base address
- int base_addr_lo = 3 + tsz - stride * (3 - start_lookup_level) -
- grain_size;
+ int base_addr_lo = 3 + tsz - stride * (3 - start_lookup_level) - tg;
Addr base_addr = mbits(ttbr, 47, base_addr_lo);
// Determine physical address size and raise an Address Size Fault if
// Determine descriptor address
Addr desc_addr = base_addr |
(bits(currState->vaddr, tsz - 1,
- stride * (3 - start_lookup_level) + grain_size) << 3);
+ stride * (3 - start_lookup_level) + tg) << 3);
// Trickbox address check
Fault f = tlb->walkTrickBoxCheck(desc_addr, currState->isSecure,
currState->longDesc.lookupLevel = start_lookup_level;
currState->longDesc.aarch64 = true;
- currState->longDesc.largeGrain = large_grain;
- currState->longDesc.grainSize = grain_size;
+ currState->longDesc.grainSize = tg;
if (currState->timing) {
Event *event;
/*
- * Copyright (c) 2010-2013 ARM Limited
+ * Copyright (c) 2010-2014 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
};
+ // Granule sizes for AArch64 long descriptors
+ enum GrainSize {
+ Grain4KB = 12,
+ Grain16KB = 14,
+ Grain64KB = 16,
+ ReservedGrain = 0
+ };
+
/** Long-descriptor format (LPAE) */
class LongDescriptor : public DescriptorBase {
public:
/** True if the current lookup is performed in AArch64 state */
bool aarch64;
- /** True if the granule size is 64 KB (AArch64 only) */
- bool largeGrain;
-
/** Width of the granule size in bits */
- int grainSize;
+ GrainSize grainSize;
/** Return the descriptor type */
EntryType type() const
switch (bits(data, 1, 0)) {
case 0x1:
// In AArch64 blocks are not allowed at L0 for the 4 KB granule
- // and at L1 for the 64 KB granule
- if (largeGrain)
+ // and at L1 for 16/64 KB granules
+ if (grainSize > Grain4KB)
return lookupLevel == L2 ? Block : Invalid;
return lookupLevel == L0 || lookupLevel == L3 ? Invalid : Block;
case 0x3:
/** Return the bit width of the page/block offset */
uint8_t offsetBits() const
{
- assert(type() == Block || type() == Page);
- if (largeGrain) {
- if (type() == Block)
- return 29 /* 512 MB */;
- return 16 /* 64 KB */; // type() == Page
+ if (type() == Block) {
+ switch (grainSize) {
+ case Grain4KB:
+ return lookupLevel == L1 ? 30 /* 1 GB */
+ : 21 /* 2 MB */;
+ case Grain16KB:
+ return 25 /* 32 MB */;
+ case Grain64KB:
+ return 29 /* 512 MB */;
+ default:
+ panic("Invalid AArch64 VM granule size\n");
+ }
+ } else if (type() == Page) {
+ switch (grainSize) {
+ case Grain4KB:
+ case Grain16KB:
+ case Grain64KB:
+ return grainSize; /* enum -> uint okay */
+ default:
+ panic("Invalid AArch64 VM granule size\n");
+ }
} else {
- if (type() == Block)
- return lookupLevel == L1 ? 30 /* 1 GB */ : 21 /* 2 MB */;
- return 12 /* 4 KB */; // type() == Page
+ panic("AArch64 page table entry must be block or page\n");
}
}
/** Cached copy of the cpsr as it existed when translation began */
CPSR cpsr;
- /** Cached copy of the ttbcr as it existed when translation began. */
- TTBCR ttbcr;
+ /** Cached copy of ttbcr/tcr as it existed when translation began */
+ union {
+ TTBCR ttbcr; // AArch32 translations
+ TCR tcr; // AArch64 translations
+ };
/** Cached copy of the htcr as it existed when translation began. */
HTCR htcr;
projects / gem5.git / commitdiff