[PATCH v2 01/19] iommu/arm-smmu-v3: Add a type for the STE
Eric Auger
eauger at redhat.com
Mon Nov 27 08:03:36 PST 2023
Hi Jason,
On 11/13/23 18:53, Jason Gunthorpe wrote:
> Instead of passing a naked __le16 * around to represent a STE wrap it in a
> "struct arm_smmu_ste" with an array of the correct size. This makes it
> much clearer which functions will comprise the "STE API".
>
> Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
> ---
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 54 ++++++++++-----------
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 7 ++-
> 2 files changed, 32 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> index 7445454c2af244..519749d15fbda0 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -1249,7 +1249,7 @@ static void arm_smmu_sync_ste_for_sid(struct arm_smmu_device *smmu, u32 sid)
> }
>
> static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
> - __le64 *dst)
> + struct arm_smmu_ste *dst)
> {
> /*
> * This is hideously complicated, but we only really care about
> @@ -1267,7 +1267,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
> * 2. Write everything apart from dword 0, sync, write dword 0, sync
> * 3. Update Config, sync
> */
> - u64 val = le64_to_cpu(dst[0]);
> + u64 val = le64_to_cpu(dst->data[0]);
> bool ste_live = false;
> struct arm_smmu_device *smmu = NULL;
> struct arm_smmu_ctx_desc_cfg *cd_table = NULL;
> @@ -1325,10 +1325,10 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
> else
> val |= FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_BYPASS);
>
> - dst[0] = cpu_to_le64(val);
> - dst[1] = cpu_to_le64(FIELD_PREP(STRTAB_STE_1_SHCFG,
> + dst->data[0] = cpu_to_le64(val);
> + dst->data[1] = cpu_to_le64(FIELD_PREP(STRTAB_STE_1_SHCFG,
> STRTAB_STE_1_SHCFG_INCOMING));
> - dst[2] = 0; /* Nuke the VMID */
> + dst->data[2] = 0; /* Nuke the VMID */
> /*
> * The SMMU can perform negative caching, so we must sync
> * the STE regardless of whether the old value was live.
> @@ -1343,7 +1343,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
> STRTAB_STE_1_STRW_EL2 : STRTAB_STE_1_STRW_NSEL1;
>
> BUG_ON(ste_live);
> - dst[1] = cpu_to_le64(
> + dst->data[1] = cpu_to_le64(
> FIELD_PREP(STRTAB_STE_1_S1DSS, STRTAB_STE_1_S1DSS_SSID0) |
> FIELD_PREP(STRTAB_STE_1_S1CIR, STRTAB_STE_1_S1C_CACHE_WBRA) |
> FIELD_PREP(STRTAB_STE_1_S1COR, STRTAB_STE_1_S1C_CACHE_WBRA) |
> @@ -1352,7 +1352,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
>
> if (smmu->features & ARM_SMMU_FEAT_STALLS &&
> !master->stall_enabled)
> - dst[1] |= cpu_to_le64(STRTAB_STE_1_S1STALLD);
> + dst->data[1] |= cpu_to_le64(STRTAB_STE_1_S1STALLD);
>
> val |= (cd_table->cdtab_dma & STRTAB_STE_0_S1CTXPTR_MASK) |
> FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_S1_TRANS) |
> @@ -1362,7 +1362,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
>
> if (s2_cfg) {
> BUG_ON(ste_live);
> - dst[2] = cpu_to_le64(
> + dst->data[2] = cpu_to_le64(
> FIELD_PREP(STRTAB_STE_2_S2VMID, s2_cfg->vmid) |
> FIELD_PREP(STRTAB_STE_2_VTCR, s2_cfg->vtcr) |
> #ifdef __BIG_ENDIAN
> @@ -1371,18 +1371,18 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
> STRTAB_STE_2_S2PTW | STRTAB_STE_2_S2AA64 |
> STRTAB_STE_2_S2R);
>
> - dst[3] = cpu_to_le64(s2_cfg->vttbr & STRTAB_STE_3_S2TTB_MASK);
> + dst->data[3] = cpu_to_le64(s2_cfg->vttbr & STRTAB_STE_3_S2TTB_MASK);
>
> val |= FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_S2_TRANS);
> }
>
> if (master->ats_enabled)
> - dst[1] |= cpu_to_le64(FIELD_PREP(STRTAB_STE_1_EATS,
> + dst->data[1] |= cpu_to_le64(FIELD_PREP(STRTAB_STE_1_EATS,
> STRTAB_STE_1_EATS_TRANS));
>
> arm_smmu_sync_ste_for_sid(smmu, sid);
> /* See comment in arm_smmu_write_ctx_desc() */
> - WRITE_ONCE(dst[0], cpu_to_le64(val));
> + WRITE_ONCE(dst->data[0], cpu_to_le64(val));
> arm_smmu_sync_ste_for_sid(smmu, sid);
>
> /* It's likely that we'll want to use the new STE soon */
> @@ -1390,7 +1390,8 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
> arm_smmu_cmdq_issue_cmd(smmu, &prefetch_cmd);
> }
>
> -static void arm_smmu_init_bypass_stes(__le64 *strtab, unsigned int nent, bool force)
> +static void arm_smmu_init_bypass_stes(struct arm_smmu_ste *strtab,
> + unsigned int nent, bool force)
> {
> unsigned int i;
> u64 val = STRTAB_STE_0_V;
> @@ -1401,11 +1402,11 @@ static void arm_smmu_init_bypass_stes(__le64 *strtab, unsigned int nent, bool fo
> val |= FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_BYPASS);
>
> for (i = 0; i < nent; ++i) {
> - strtab[0] = cpu_to_le64(val);
> - strtab[1] = cpu_to_le64(FIELD_PREP(STRTAB_STE_1_SHCFG,
> - STRTAB_STE_1_SHCFG_INCOMING));
> - strtab[2] = 0;
> - strtab += STRTAB_STE_DWORDS;
> + strtab->data[0] = cpu_to_le64(val);
> + strtab->data[1] = cpu_to_le64(FIELD_PREP(
> + STRTAB_STE_1_SHCFG, STRTAB_STE_1_SHCFG_INCOMING));
> + strtab->data[2] = 0;
> + strtab++;
> }
> }
>
> @@ -2209,26 +2210,22 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain)
> return 0;
> }
>
> -static __le64 *arm_smmu_get_step_for_sid(struct arm_smmu_device *smmu, u32 sid)
> +static struct arm_smmu_ste *
> +arm_smmu_get_step_for_sid(struct arm_smmu_device *smmu, u32 sid)
> {
> - __le64 *step;
> struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg;
>
> if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB) {
> - struct arm_smmu_strtab_l1_desc *l1_desc;
> int idx;
>
> /* Two-level walk */
> idx = (sid >> STRTAB_SPLIT) * STRTAB_L1_DESC_DWORDS;
> - l1_desc = &cfg->l1_desc[idx];
> - idx = (sid & ((1 << STRTAB_SPLIT) - 1)) * STRTAB_STE_DWORDS;
> - step = &l1_desc->l2ptr[idx];
> + return &cfg->l1_desc[idx].l2ptr[sid & ((1 << STRTAB_SPLIT) - 1)];
This looks less readable to me than it was before.
> } else {
> /* Simple linear lookup */
> - step = &cfg->strtab[sid * STRTAB_STE_DWORDS];
> + return (struct arm_smmu_ste *)&cfg
> + ->strtab[sid * STRTAB_STE_DWORDS];
Besides
Reviewed-by: Eric Auger <eric.auger at redhat.com>
Eric
> }
> -
> - return step;
> }
>
> static void arm_smmu_install_ste_for_dev(struct arm_smmu_master *master)
> @@ -2238,7 +2235,8 @@ static void arm_smmu_install_ste_for_dev(struct arm_smmu_master *master)
>
> for (i = 0; i < master->num_streams; ++i) {
> u32 sid = master->streams[i].id;
> - __le64 *step = arm_smmu_get_step_for_sid(smmu, sid);
> + struct arm_smmu_ste *step =
> + arm_smmu_get_step_for_sid(smmu, sid);
>
> /* Bridged PCI devices may end up with duplicated IDs */
> for (j = 0; j < i; j++)
> @@ -3769,7 +3767,7 @@ static void arm_smmu_rmr_install_bypass_ste(struct arm_smmu_device *smmu)
> iort_get_rmr_sids(dev_fwnode(smmu->dev), &rmr_list);
>
> list_for_each_entry(e, &rmr_list, list) {
> - __le64 *step;
> + struct arm_smmu_ste *step;
> struct iommu_iort_rmr_data *rmr;
> int ret, i;
>
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
> index 961205ba86d25d..03f9e526cbd92f 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
> @@ -206,6 +206,11 @@
> #define STRTAB_L1_DESC_L2PTR_MASK GENMASK_ULL(51, 6)
>
> #define STRTAB_STE_DWORDS 8
> +
> +struct arm_smmu_ste {
> + __le64 data[STRTAB_STE_DWORDS];
> +};
> +
> #define STRTAB_STE_0_V (1UL << 0)
> #define STRTAB_STE_0_CFG GENMASK_ULL(3, 1)
> #define STRTAB_STE_0_CFG_ABORT 0
> @@ -571,7 +576,7 @@ struct arm_smmu_priq {
> struct arm_smmu_strtab_l1_desc {
> u8 span;
>
> - __le64 *l2ptr;
> + struct arm_smmu_ste *l2ptr;
> dma_addr_t l2ptr_dma;
> };
>
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