[PATCH v3] IOMMU: SMMUv2: Support for Extended Stream ID (16 bit)
From: Aleksey Makarov
Date: Tue Jan 17 2017 - 10:15:25 EST
Enable the Extended Stream ID feature when available.
This patch on top of series "KVM PCIe/MSI passthrough on ARM/ARM64
and IOVA reserved regions" by Eric Auger [1] allows to passthrough
an external PCIe network card on a ThunderX server successfully.
Without this patch that card caused a warning like
pci 0006:90:00.0: stream ID 0x9000 out of range for SMMU (0x7fff)
during boot.
[1] https://lkml.kernel.org/r/1484127714-3263-1-git-send-email-eric.auger@xxxxxxxxxx
Signed-off-by: Aleksey Makarov <aleksey.makarov@xxxxxxxxxx>
---
v3:
- keep formatting of the comment
- fix printk message after the deleted chunk. "[Do] not print a mask
here, since it's not overly interesting in itself, and add_device will
still show the offending mask in full if it ever actually matters (as in
the commit message)." (Robin Murphy)
v2:
https://lkml.kernel.org/r/20170116141111.29444-1-aleksey.makarov@xxxxxxxxxx
- remove unnecessary parentheses (Robin Murphy)
- refactor testing SMR fields to after setting sCR0 as theirs width
depends on sCR0_EXIDENABLE (Robin Murphy)
v1 (rfc):
https://lkml.kernel.org/r/20170110115755.19102-1-aleksey.makarov@xxxxxxxxxx
drivers/iommu/arm-smmu.c | 69 +++++++++++++++++++++++++++++++++---------------
1 file changed, 48 insertions(+), 21 deletions(-)
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 13d26009b8e0..861cc135722f 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -24,6 +24,7 @@
* - v7/v8 long-descriptor format
* - Non-secure access to the SMMU
* - Context fault reporting
+ * - Extended Stream ID (16 bit)
*/
#define pr_fmt(fmt) "arm-smmu: " fmt
@@ -87,6 +88,7 @@
#define sCR0_CLIENTPD (1 << 0)
#define sCR0_GFRE (1 << 1)
#define sCR0_GFIE (1 << 2)
+#define sCR0_EXIDENABLE (1 << 3)
#define sCR0_GCFGFRE (1 << 4)
#define sCR0_GCFGFIE (1 << 5)
#define sCR0_USFCFG (1 << 10)
@@ -126,6 +128,7 @@
#define ID0_NUMIRPT_MASK 0xff
#define ID0_NUMSIDB_SHIFT 9
#define ID0_NUMSIDB_MASK 0xf
+#define ID0_EXIDS (1 << 8)
#define ID0_NUMSMRG_SHIFT 0
#define ID0_NUMSMRG_MASK 0xff
@@ -169,6 +172,7 @@
#define ARM_SMMU_GR0_S2CR(n) (0xc00 + ((n) << 2))
#define S2CR_CBNDX_SHIFT 0
#define S2CR_CBNDX_MASK 0xff
+#define S2CR_EXIDVALID (1 << 10)
#define S2CR_TYPE_SHIFT 16
#define S2CR_TYPE_MASK 0x3
enum arm_smmu_s2cr_type {
@@ -354,6 +358,7 @@ struct arm_smmu_device {
#define ARM_SMMU_FEAT_FMT_AARCH64_64K (1 << 9)
#define ARM_SMMU_FEAT_FMT_AARCH32_L (1 << 10)
#define ARM_SMMU_FEAT_FMT_AARCH32_S (1 << 11)
+#define ARM_SMMU_FEAT_EXIDS (1 << 12)
u32 features;
#define ARM_SMMU_OPT_SECURE_CFG_ACCESS (1 << 0)
@@ -1051,7 +1056,7 @@ static void arm_smmu_write_smr(struct arm_smmu_device *smmu, int idx)
struct arm_smmu_smr *smr = smmu->smrs + idx;
u32 reg = smr->id << SMR_ID_SHIFT | smr->mask << SMR_MASK_SHIFT;
- if (smr->valid)
+ if (!(smmu->features & ARM_SMMU_FEAT_EXIDS) && smr->valid)
reg |= SMR_VALID;
writel_relaxed(reg, ARM_SMMU_GR0(smmu) + ARM_SMMU_GR0_SMR(idx));
}
@@ -1063,6 +1068,9 @@ static void arm_smmu_write_s2cr(struct arm_smmu_device *smmu, int idx)
(s2cr->cbndx & S2CR_CBNDX_MASK) << S2CR_CBNDX_SHIFT |
(s2cr->privcfg & S2CR_PRIVCFG_MASK) << S2CR_PRIVCFG_SHIFT;
+ if (smmu->features & ARM_SMMU_FEAT_EXIDS && smmu->smrs &&
+ smmu->smrs[idx].valid)
+ reg |= S2CR_EXIDVALID;
writel_relaxed(reg, ARM_SMMU_GR0(smmu) + ARM_SMMU_GR0_S2CR(idx));
}
@@ -1073,6 +1081,34 @@ static void arm_smmu_write_sme(struct arm_smmu_device *smmu, int idx)
arm_smmu_write_smr(smmu, idx);
}
+/*
+ * The width of SMR's mask field depends on sCR0_EXIDENABLE, so this function
+ * should be called after sCR0 is written.
+ */
+static void arm_smmu_test_smr_masks(struct arm_smmu_device *smmu)
+{
+ void __iomem *gr0_base = ARM_SMMU_GR0(smmu);
+ u32 smr;
+
+ if (!smmu->smrs)
+ return;
+
+ /*
+ * SMR.ID bits may not be preserved if the corresponding MASK
+ * bits are set, so check each one separately. We can reject
+ * masters later if they try to claim IDs outside these masks.
+ */
+ smr = smmu->streamid_mask << SMR_ID_SHIFT;
+ writel_relaxed(smr, gr0_base + ARM_SMMU_GR0_SMR(0));
+ smr = readl_relaxed(gr0_base + ARM_SMMU_GR0_SMR(0));
+ smmu->streamid_mask = smr >> SMR_ID_SHIFT;
+
+ smr = smmu->streamid_mask << SMR_MASK_SHIFT;
+ writel_relaxed(smr, gr0_base + ARM_SMMU_GR0_SMR(0));
+ smr = readl_relaxed(gr0_base + ARM_SMMU_GR0_SMR(0));
+ smmu->smr_mask_mask = smr >> SMR_MASK_SHIFT;
+}
+
static int arm_smmu_find_sme(struct arm_smmu_device *smmu, u16 id, u16 mask)
{
struct arm_smmu_smr *smrs = smmu->smrs;
@@ -1674,6 +1710,9 @@ static void arm_smmu_device_reset(struct arm_smmu_device *smmu)
if (smmu->features & ARM_SMMU_FEAT_VMID16)
reg |= sCR0_VMID16EN;
+ if (smmu->features & ARM_SMMU_FEAT_EXIDS)
+ reg |= sCR0_EXIDENABLE;
+
/* Push the button */
__arm_smmu_tlb_sync(smmu);
writel(reg, ARM_SMMU_GR0_NS(smmu) + ARM_SMMU_GR0_sCR0);
@@ -1761,11 +1800,14 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
"\t(IDR0.CTTW overridden by FW configuration)\n");
/* Max. number of entries we have for stream matching/indexing */
- size = 1 << ((id >> ID0_NUMSIDB_SHIFT) & ID0_NUMSIDB_MASK);
+ if (smmu->version == ARM_SMMU_V2 && id & ID0_EXIDS) {
+ smmu->features |= ARM_SMMU_FEAT_EXIDS;
+ size = 1 << 16;
+ } else {
+ size = 1 << ((id >> ID0_NUMSIDB_SHIFT) & ID0_NUMSIDB_MASK);
+ }
smmu->streamid_mask = size - 1;
if (id & ID0_SMS) {
- u32 smr;
-
smmu->features |= ARM_SMMU_FEAT_STREAM_MATCH;
size = (id >> ID0_NUMSMRG_SHIFT) & ID0_NUMSMRG_MASK;
if (size == 0) {
@@ -1774,21 +1816,6 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
return -ENODEV;
}
- /*
- * SMR.ID bits may not be preserved if the corresponding MASK
- * bits are set, so check each one separately. We can reject
- * masters later if they try to claim IDs outside these masks.
- */
- smr = smmu->streamid_mask << SMR_ID_SHIFT;
- writel_relaxed(smr, gr0_base + ARM_SMMU_GR0_SMR(0));
- smr = readl_relaxed(gr0_base + ARM_SMMU_GR0_SMR(0));
- smmu->streamid_mask = smr >> SMR_ID_SHIFT;
-
- smr = smmu->streamid_mask << SMR_MASK_SHIFT;
- writel_relaxed(smr, gr0_base + ARM_SMMU_GR0_SMR(0));
- smr = readl_relaxed(gr0_base + ARM_SMMU_GR0_SMR(0));
- smmu->smr_mask_mask = smr >> SMR_MASK_SHIFT;
-
/* Zero-initialised to mark as invalid */
smmu->smrs = devm_kcalloc(smmu->dev, size, sizeof(*smmu->smrs),
GFP_KERNEL);
@@ -1796,8 +1823,7 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
return -ENOMEM;
dev_notice(smmu->dev,
- "\tstream matching with %lu register groups, mask 0x%x",
- size, smmu->smr_mask_mask);
+ "\tstream matching with %lu register groups", size);
}
/* s2cr->type == 0 means translation, so initialise explicitly */
smmu->s2crs = devm_kmalloc_array(smmu->dev, size, sizeof(*smmu->s2crs),
@@ -2120,6 +2146,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
iommu_register_instance(dev->fwnode, &arm_smmu_ops);
platform_set_drvdata(pdev, smmu);
arm_smmu_device_reset(smmu);
+ arm_smmu_test_smr_masks(smmu);
/* Oh, for a proper bus abstraction */
if (!iommu_present(&platform_bus_type))
--
2.11.0