diff options
Diffstat (limited to 'src/dev/arm')
| -rw-r--r-- | src/dev/arm/smmu_v3_cmdexec.cc | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/src/dev/arm/smmu_v3_cmdexec.cc b/src/dev/arm/smmu_v3_cmdexec.cc index 48896bf96..5b9dc6e4a 100644 --- a/src/dev/arm/smmu_v3_cmdexec.cc +++ b/src/dev/arm/smmu_v3_cmdexec.cc @@ -56,20 +56,28 @@ SMMUCommandExecProcess::main(Yield &yield) busy = true; while (true) { - int sizeMask = mask(smmu.regs.cmdq_base & Q_BASE_SIZE_MASK); + // Masking depending on CMDQ_BASE.LOG2SIZE (log(number of + // queue entries)). Example: a value of 0b101 (32 entries) + // generates a 0b11111 mask. + int size_mask = mask( + smmu.regs.cmdq_base & Q_BASE_SIZE_MASK); - if ((smmu.regs.cmdq_cons & sizeMask) == - (smmu.regs.cmdq_prod & sizeMask)) + // In this case the wrap bit is considered (+1) + int size_mask_wrap = mask( + (smmu.regs.cmdq_base & Q_BASE_SIZE_MASK) + 1); + + if ((smmu.regs.cmdq_cons & size_mask_wrap) == + (smmu.regs.cmdq_prod & size_mask_wrap)) break; // command queue empty - Addr cmdAddr = + Addr cmd_addr = (smmu.regs.cmdq_base & Q_BASE_ADDR_MASK) + - (smmu.regs.cmdq_cons & sizeMask) * sizeof(SMMUCommand); + (smmu.regs.cmdq_cons & size_mask) * sizeof(SMMUCommand); // This deliberately resets the error field in cmdq_cons! - smmu.regs.cmdq_cons = (smmu.regs.cmdq_cons + 1) & sizeMask; + smmu.regs.cmdq_cons = (smmu.regs.cmdq_cons + 1) & size_mask_wrap; - doRead(yield, cmdAddr, &cmd, sizeof(SMMUCommand)); + doRead(yield, cmd_addr, &cmd, sizeof(SMMUCommand)); smmu.processCommand(cmd); } |