On Wed, Dec 18, 2019 at 10:59:36AM +0100, Auger Eric wrote:
> > struct arm_smmu_s1_cfg {
> > - struct arm_smmu_cd_table table;
> > + struct arm_smmu_cd_table *tables;
> > + size_t num_tables;
> > + __le64 *l1ptr;
> you may add a comment saying that l1ptr and l1ptr_dma are only set/used
> in non linear case and one comment saying that "tables" represent leaf
> tables.
I now have
/* Leaf tables or linear table */
and
/* First level tables, when two level are used */
but I'm not entirely convinced it adds value
> > + dma_addr_t l1ptr_dma;
> > struct arm_smmu_ctx_desc cd;
> > u8 s1fmt;
> > u8 s1cdmax;
> > @@ -1521,9 +1538,53 @@ static void arm_smmu_free_cd_leaf_table(struct arm_smmu_device *smmu,
> > {
> > size_t size = num_entries * (CTXDESC_CD_DWORDS << 3);
> >
> > + if (!table->ptr)
> > + return;
> > dmam_free_coherent(smmu->dev, size, table->ptr, table->ptr_dma);
> > }
> >
> > +static void arm_smmu_write_cd_l1_desc(__le64 *dst,
> > + struct arm_smmu_cd_table *table)
> > +{
> > + u64 val = (table->ptr_dma & CTXDESC_L1_DESC_L2PTR_MASK) |
> > + CTXDESC_L1_DESC_VALID;
> > +
> > + WRITE_ONCE(*dst, cpu_to_le64(val));
> > +}
> > +
> > +static __le64 *arm_smmu_get_cd_ptr(struct arm_smmu_domain *smmu_domain,
> > + u32 ssid)
> > +{
> > + __le64 *l1ptr;
> > + unsigned int idx;
> > + struct arm_smmu_cd_table *table;
> > + struct arm_smmu_device *smmu = smmu_domain->smmu;
> > + struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
> > +
> > + if (cfg->s1fmt == STRTAB_STE_0_S1FMT_LINEAR) {
> > + table = &cfg->tables[0];
> > + idx = ssid;
> > + } else {
> nit: you may avoid this extra indent by either returning above or go to
> a label.
> > + idx = ssid >> CTXDESC_SPLIT;
> > + if (idx >= cfg->num_tables)
> > + return NULL;
> > +
> > + table = &cfg->tables[idx];
> > + if (!table->ptr) {
> > + if (arm_smmu_alloc_cd_leaf_table(smmu, table,
> > + CTXDESC_L2_ENTRIES))
> > + return NULL;
> > +
> > + l1ptr = cfg->l1ptr + idx * CTXDESC_L1_DESC_DWORDS;
> > + arm_smmu_write_cd_l1_desc(l1ptr, table);
> > + /* An invalid L1CD can be cached */
> > + arm_smmu_sync_cd(smmu_domain, ssid, false);
> > + }
> > + idx = ssid & (CTXDESC_L2_ENTRIES - 1);
> > + }
> > + return table->ptr + idx * CTXDESC_CD_DWORDS;> +}
> > +
> > static u64 arm_smmu_cpu_tcr_to_cd(u64 tcr)
> > {
> > u64 val = 0;
> > @@ -1556,8 +1617,10 @@ static int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain,
> > u64 val;
> > bool cd_live;
> > struct arm_smmu_device *smmu = smmu_domain->smmu;
> > - __le64 *cdptr = smmu_domain->s1_cfg.table.ptr + ssid *
> > - CTXDESC_CD_DWORDS;
> > + __le64 *cdptr = arm_smmu_get_cd_ptr(smmu_domain, ssid);
> > +
> > + if (!cdptr)
> > + return -ENOMEM;
> -ENOMEM does not fit well with (idx >= cfg->num_tables) case
> Besides the idx is checked against the max table capacity only in non
> linear mode. Can't you check the ssid against cfg->s1cdmax earlier?
Ok, I'll move that check here
Thanks,
Jean
