diff options
| -rw-r--r-- | src/dev/arm/gic_pl390.cc | 26 | ||||
| -rw-r--r-- | src/dev/arm/gic_pl390.hh | 5 |
2 files changed, 26 insertions, 5 deletions
diff --git a/src/dev/arm/gic_pl390.cc b/src/dev/arm/gic_pl390.cc index e7f3e32ef..c114604ab 100644 --- a/src/dev/arm/gic_pl390.cc +++ b/src/dev/arm/gic_pl390.cc @@ -83,7 +83,7 @@ Pl390::Pl390(const Params *p) iccrpr[x] = 0xff; cpuEnabled[x] = false; cpuPriority[x] = 0xff; - cpuBpr[x] = 0; + cpuBpr[x] = GICC_BPR_MINIMUM; // Initialize cpu highest int cpuHighestInt[x] = SPURIOUS_INT; postIntEvent[x] = new PostIntEvent(*this, x); @@ -538,9 +538,13 @@ Pl390::writeCpu(ContextID ctx, Addr daddr, uint32_t data) case GICC_PMR: cpuPriority[ctx] = data; break; - case GICC_BPR: - cpuBpr[ctx] = data; + case GICC_BPR: { + auto bpr = data & 0x7; + if (bpr < GICC_BPR_MINIMUM) + bpr = GICC_BPR_MINIMUM; + cpuBpr[ctx] = bpr; break; + } case GICC_EOIR: { const IAR iar = data; if (iar.ack_id < SGI_MAX) { @@ -666,6 +670,17 @@ Pl390::genSwiMask(int cpu) return ULL(0x0101010101010101) << cpu; } +uint8_t +Pl390::getCpuPriority(unsigned cpu) +{ + // see Table 3-2 in IHI0048B.b (GICv2) + // mask some low-order priority bits per BPR value + // NB: the GIC prioritization scheme is upside down: + // lower values are higher priority; masking off bits + // actually creates a higher priority, not lower. + return cpuPriority[cpu] & (0xff00 >> (7 - cpuBpr[cpu])); +} + void Pl390::updateIntState(int hint) { @@ -676,7 +691,7 @@ Pl390::updateIntState(int hint) /*@todo use hint to do less work. */ int highest_int = SPURIOUS_INT; // Priorities below that set in GICC_PMR can be ignored - uint8_t highest_pri = cpuPriority[cpu]; + uint8_t highest_pri = getCpuPriority(cpu); // Check SGIs for (int swi = 0; swi < SGI_MAX; swi++) { @@ -733,7 +748,8 @@ Pl390::updateIntState(int hint) /* @todo make this work for more than one cpu, need to handle 1:N, N:N * models */ - if (enabled && cpuEnabled[cpu] && (highest_pri < cpuPriority[cpu]) && + if (enabled && cpuEnabled[cpu] && + (highest_pri < getCpuPriority(cpu)) && !(getActiveInt(cpu, intNumToWord(highest_int)) & (1 << intNumToBit(highest_int)))) { diff --git a/src/dev/arm/gic_pl390.hh b/src/dev/arm/gic_pl390.hh index 210f91cfc..8beb5e2d5 100644 --- a/src/dev/arm/gic_pl390.hh +++ b/src/dev/arm/gic_pl390.hh @@ -111,6 +111,10 @@ class Pl390 : public BaseGic static const int INT_LINES_MAX = 1020; static const int GLOBAL_INT_LINES = INT_LINES_MAX - SGI_MAX - PPI_MAX; + /** minimum value for Binary Point Register ("IMPLEMENTATION DEFINED"); + chosen for consistency with Linux's in-kernel KVM GIC model */ + static const int GICC_BPR_MINIMUM = 2; + BitUnion32(SWI) Bitfield<3,0> sgi_id; Bitfield<23,16> cpu_list; @@ -276,6 +280,7 @@ class Pl390 : public BaseGic /** CPU priority */ uint8_t cpuPriority[CPU_MAX]; + uint8_t getCpuPriority(unsigned cpu); // BPR-adjusted priority value /** Binary point registers */ uint8_t cpuBpr[CPU_MAX]; |