diff options
Diffstat (limited to 'drivers/iommu/arm-smmu-v3.c')
| -rw-r--r-- | drivers/iommu/arm-smmu-v3.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index f04c13d52598..be788aee14e7 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -86,6 +86,12 @@ #define IDR5_VAX GENMASK(11, 10) #define IDR5_VAX_52_BIT 1 +#define ARM_SMMU_IIDR 0x18 +#define IIDR_CN96XX_A0 0x2b20034c +#define IIDR_CN96XX_B0 0x2b20134c +#define IIDR_CN95XX_A0 0x2b30034c +#define IIDR_CN95XX_A1 0x2b30134c + #define ARM_SMMU_CR0 0x20 #define CR0_ATSCHK (1 << 4) #define CR0_CMDQEN (1 << 3) @@ -558,6 +564,7 @@ struct arm_smmu_device { #define ARM_SMMU_OPT_SKIP_PREFETCH (1 << 0) #define ARM_SMMU_OPT_PAGE0_REGS_ONLY (1 << 1) +#define ARM_SMMU_OPT_FORCE_QDRAIN (1 << 2) u32 options; struct arm_smmu_cmdq cmdq; @@ -945,6 +952,12 @@ static void arm_smmu_cmdq_insert_cmd(struct arm_smmu_device *smmu, u64 *cmd) smmu->prev_cmd_opcode = FIELD_GET(CMDQ_0_OP, cmd[0]); + if (smmu->options & ARM_SMMU_OPT_FORCE_QDRAIN) { + /* Ensure command queue has atmost two entries */ + if (!(q->prod & 0x1) && queue_poll_cons(q, true, false)) + dev_err(smmu->dev, "command drain timeout\n"); + } + while (queue_insert_raw(q, cmd) == -ENOSPC) { if (queue_poll_cons(q, false, wfe)) dev_err_ratelimited(smmu->dev, "CMDQ timeout\n"); @@ -2970,6 +2983,25 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu) dev_info(smmu->dev, "ias %lu-bit, oas %lu-bit (features 0x%08x)\n", smmu->ias, smmu->oas, smmu->features); + + /* Options based on implementation */ + reg = readl_relaxed(smmu->base + ARM_SMMU_IIDR); + + /* Marvell Octeontx2 SMMU wrongly issues unsupported + * 64 byte memory reads under certain conditions for + * reading commands from the command queue. + * Force command queue drain for every two writes, + * so that SMMU issues only 32 byte reads. + */ + switch (reg) { + case IIDR_CN96XX_A0: + case IIDR_CN96XX_B0: + case IIDR_CN95XX_A0: + case IIDR_CN95XX_A1: + smmu->options |= ARM_SMMU_OPT_FORCE_QDRAIN; + break; + } + return 0; } |