On Fri, Jun 26, 2015 at 09:33:04AM +0100, Zhen Lei wrote: > Some broken SMMUv3 devices treat CMD_PREFETCH_CONFIG as illegal command, > it's ugly to print error information. CMD_PREFETCH_CONFIG is just used to > prefetch the configuration for a specified StreamID, without this command > will not impact SMMUv3 function. > > Signed-off-by: Zhen Lei <[email protected]> > --- > drivers/iommu/arm-smmu-v3.c | 18 ++++++++++++++---- > 1 file changed, 14 insertions(+), 4 deletions(-) > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index d799feb..3971aef 100644 > --- a/drivers/iommu/arm-smmu-v3.c > +++ b/drivers/iommu/arm-smmu-v3.c > @@ -813,6 +813,7 @@ static void arm_smmu_cmdq_skip_err(struct arm_smmu_device > *smmu) > }; > > int i; > + u32 opcode; > u64 cmd[CMDQ_ENT_DWORDS]; > struct arm_smmu_queue *q = &smmu->cmdq.q; > u32 cons = readl_relaxed(q->cons_reg); > @@ -821,15 +822,14 @@ static void arm_smmu_cmdq_skip_err(struct > arm_smmu_device *smmu) > .opcode = CMDQ_OP_CMD_SYNC, > }; > > - dev_err(smmu->dev, "CMDQ error (cons 0x%08x): %s\n", cons, > - cerror_str[idx]); > - > switch (idx) { > case CMDQ_ERR_CERROR_ILL_IDX: > break; > case CMDQ_ERR_CERROR_ABT_IDX: > - dev_err(smmu->dev, "retrying command fetch\n"); > case CMDQ_ERR_CERROR_NONE_IDX: > + dev_err(smmu->dev, "CMDQ error (cons 0x%08x): %s\n", cons, > + cerror_str[idx]); > + dev_err(smmu->dev, "retrying command execution\n");
Why are you making this (unrelated) change? Out of interest, did the gerror code manage to turn the prefetch into a SYNC, as intended? > return; > } > > @@ -838,10 +838,20 @@ static void arm_smmu_cmdq_skip_err(struct > arm_smmu_device *smmu) > * not to touch any of the shadow cmdq state. > */ > queue_read(cmd, Q_ENT(q, idx), q->ent_dwords); > + > + /* > + * Some broken SMMUv3 devices treat CMD_PREFETCH_CONFIG as illegal > + * command, it's ugly to print error information. > + */ > + opcode = (cmd[0] >> CMDQ_0_OP_SHIFT) & CMDQ_0_OP_MASK; > + if (opcode == CMDQ_OP_PREFETCH_CFG) > + goto skip_error_command; > + I think a better way to fix this would be to add a quick to the device-tree along the lines of "hisilicon,broken-prefetch-cmd" which we could check before issuing the prefetch command in arm_smmu_write_strtab_ent. Something along the lines of the arm_smmu_options in arm-smmu.c would be a good basis for quirks. Will _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
