Allows userspace to check for SMMUv3 features.
Expose the following RO registers related to ARM SMMUv3 via sysfs:
SMMU_IDR0
SMMU_IDR1
SMMU_IDR2
SMMU_IDR3
SMMU_IDR4
SMMU_IDR5
SMMU_IDR6
SMMU_IIDR
SMMU_AIDR
# find /sys | grep arm-iommu
/sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu
/sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr5
/sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr3
/sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr1
/sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_aidr
/sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr6
/sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr4
/sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_iidr
/sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr2
/sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr0
Signed-off-by: Miguel Luis <[email protected]>
---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 199 ++++++++++++++++----
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 27 +++
2 files changed, 191 insertions(+), 35 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 6dc6d8b6b368..7f779d3f88f2 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -3424,17 +3424,16 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
{
- u32 reg;
bool coherent = smmu->features & ARM_SMMU_FEAT_COHERENCY;
/* IDR0 */
- reg = readl_relaxed(smmu->base + ARM_SMMU_IDR0);
+ smmu->idr0 = readl_relaxed(smmu->base + ARM_SMMU_IDR0);
/* 2-level structures */
- if (FIELD_GET(IDR0_ST_LVL, reg) == IDR0_ST_LVL_2LVL)
+ if (FIELD_GET(IDR0_ST_LVL, smmu->idr0) == IDR0_ST_LVL_2LVL)
smmu->features |= ARM_SMMU_FEAT_2_LVL_STRTAB;
- if (reg & IDR0_CD2L)
+ if (smmu->idr0 & IDR0_CD2L)
smmu->features |= ARM_SMMU_FEAT_2_LVL_CDTAB;
/*
@@ -3442,7 +3441,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
* We currently require the same endianness as the CPU, but this
* could be changed later by adding a new IO_PGTABLE_QUIRK.
*/
- switch (FIELD_GET(IDR0_TTENDIAN, reg)) {
+ switch (FIELD_GET(IDR0_TTENDIAN, smmu->idr0)) {
case IDR0_TTENDIAN_MIXED:
smmu->features |= ARM_SMMU_FEAT_TT_LE | ARM_SMMU_FEAT_TT_BE;
break;
@@ -3461,22 +3460,22 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
}
/* Boolean feature flags */
- if (IS_ENABLED(CONFIG_PCI_PRI) && reg & IDR0_PRI)
+ if (IS_ENABLED(CONFIG_PCI_PRI) && smmu->idr0 & IDR0_PRI)
smmu->features |= ARM_SMMU_FEAT_PRI;
- if (IS_ENABLED(CONFIG_PCI_ATS) && reg & IDR0_ATS)
+ if (IS_ENABLED(CONFIG_PCI_ATS) && smmu->idr0 & IDR0_ATS)
smmu->features |= ARM_SMMU_FEAT_ATS;
- if (reg & IDR0_SEV)
+ if (smmu->idr0 & IDR0_SEV)
smmu->features |= ARM_SMMU_FEAT_SEV;
- if (reg & IDR0_MSI) {
+ if (smmu->idr0 & IDR0_MSI) {
smmu->features |= ARM_SMMU_FEAT_MSI;
if (coherent && !disable_msipolling)
smmu->options |= ARM_SMMU_OPT_MSIPOLL;
}
- if (reg & IDR0_HYP) {
+ if (smmu->idr0 & IDR0_HYP) {
smmu->features |= ARM_SMMU_FEAT_HYP;
if (cpus_have_cap(ARM64_HAS_VIRT_HOST_EXTN))
smmu->features |= ARM_SMMU_FEAT_E2H;
@@ -3486,11 +3485,11 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
* The coherency feature as set by FW is used in preference to the ID
* register, but warn on mismatch.
*/
- if (!!(reg & IDR0_COHACC) != coherent)
+ if (!!(smmu->idr0 & IDR0_COHACC) != coherent)
dev_warn(smmu->dev, "IDR0.COHACC overridden by FW configuration (%s)\n",
coherent ? "true" : "false");
- switch (FIELD_GET(IDR0_STALL_MODEL, reg)) {
+ switch (FIELD_GET(IDR0_STALL_MODEL, smmu->idr0)) {
case IDR0_STALL_MODEL_FORCE:
smmu->features |= ARM_SMMU_FEAT_STALL_FORCE;
fallthrough;
@@ -3498,19 +3497,19 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
smmu->features |= ARM_SMMU_FEAT_STALLS;
}
- if (reg & IDR0_S1P)
+ if (smmu->idr0 & IDR0_S1P)
smmu->features |= ARM_SMMU_FEAT_TRANS_S1;
- if (reg & IDR0_S2P)
+ if (smmu->idr0 & IDR0_S2P)
smmu->features |= ARM_SMMU_FEAT_TRANS_S2;
- if (!(reg & (IDR0_S1P | IDR0_S2P))) {
+ if (!(smmu->idr0 & (IDR0_S1P | IDR0_S2P))) {
dev_err(smmu->dev, "no translation support!\n");
return -ENXIO;
}
/* We only support the AArch64 table format at present */
- switch (FIELD_GET(IDR0_TTF, reg)) {
+ switch (FIELD_GET(IDR0_TTF, smmu->idr0)) {
case IDR0_TTF_AARCH32_64:
smmu->ias = 40;
fallthrough;
@@ -3522,19 +3521,20 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
}
/* ASID/VMID sizes */
- smmu->asid_bits = reg & IDR0_ASID16 ? 16 : 8;
- smmu->vmid_bits = reg & IDR0_VMID16 ? 16 : 8;
+ smmu->asid_bits = smmu->idr0 & IDR0_ASID16 ? 16 : 8;
+ smmu->vmid_bits = smmu->idr0 & IDR0_VMID16 ? 16 : 8;
/* IDR1 */
- reg = readl_relaxed(smmu->base + ARM_SMMU_IDR1);
- if (reg & (IDR1_TABLES_PRESET | IDR1_QUEUES_PRESET | IDR1_REL)) {
+ smmu->idr1 = readl_relaxed(smmu->base + ARM_SMMU_IDR1);
+
+ if (smmu->idr1 & (IDR1_TABLES_PRESET | IDR1_QUEUES_PRESET | IDR1_REL)) {
dev_err(smmu->dev, "embedded implementation not supported\n");
return -ENXIO;
}
/* Queue sizes, capped to ensure natural alignment */
smmu->cmdq.q.llq.max_n_shift = min_t(u32, CMDQ_MAX_SZ_SHIFT,
- FIELD_GET(IDR1_CMDQS, reg));
+ FIELD_GET(IDR1_CMDQS, smmu->idr1));
if (smmu->cmdq.q.llq.max_n_shift <= ilog2(CMDQ_BATCH_ENTRIES)) {
/*
* We don't support splitting up batches, so one batch of
@@ -3548,13 +3548,13 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
}
smmu->evtq.q.llq.max_n_shift = min_t(u32, EVTQ_MAX_SZ_SHIFT,
- FIELD_GET(IDR1_EVTQS, reg));
+ FIELD_GET(IDR1_EVTQS, smmu->idr1));
smmu->priq.q.llq.max_n_shift = min_t(u32, PRIQ_MAX_SZ_SHIFT,
- FIELD_GET(IDR1_PRIQS, reg));
+ FIELD_GET(IDR1_PRIQS, smmu->idr1));
/* SID/SSID sizes */
- smmu->ssid_bits = FIELD_GET(IDR1_SSIDSIZE, reg);
- smmu->sid_bits = FIELD_GET(IDR1_SIDSIZE, reg);
+ smmu->ssid_bits = FIELD_GET(IDR1_SSIDSIZE, smmu->idr1);
+ smmu->sid_bits = FIELD_GET(IDR1_SIDSIZE, smmu->idr1);
/*
* If the SMMU supports fewer bits than would fill a single L2 stream
@@ -3563,31 +3563,37 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
if (smmu->sid_bits <= STRTAB_SPLIT)
smmu->features &= ~ARM_SMMU_FEAT_2_LVL_STRTAB;
+ /* IDR2 */
+ smmu->idr2 = readl_relaxed(smmu->base + ARM_SMMU_IDR2);
+
/* IDR3 */
- reg = readl_relaxed(smmu->base + ARM_SMMU_IDR3);
- if (FIELD_GET(IDR3_RIL, reg))
+ smmu->idr3 = readl_relaxed(smmu->base + ARM_SMMU_IDR3);
+ if (FIELD_GET(IDR3_RIL, smmu->idr3))
smmu->features |= ARM_SMMU_FEAT_RANGE_INV;
+ /* IDR4 */
+ smmu->idr4 = readl_relaxed(smmu->base + ARM_SMMU_IDR4);
+
/* IDR5 */
- reg = readl_relaxed(smmu->base + ARM_SMMU_IDR5);
+ smmu->idr5 = readl_relaxed(smmu->base + ARM_SMMU_IDR5);
/* Maximum number of outstanding stalls */
- smmu->evtq.max_stalls = FIELD_GET(IDR5_STALL_MAX, reg);
+ smmu->evtq.max_stalls = FIELD_GET(IDR5_STALL_MAX, smmu->idr5);
/* Page sizes */
- if (reg & IDR5_GRAN64K)
+ if (smmu->idr5 & IDR5_GRAN64K)
smmu->pgsize_bitmap |= SZ_64K | SZ_512M;
- if (reg & IDR5_GRAN16K)
+ if (smmu->idr5 & IDR5_GRAN16K)
smmu->pgsize_bitmap |= SZ_16K | SZ_32M;
- if (reg & IDR5_GRAN4K)
+ if (smmu->idr5 & IDR5_GRAN4K)
smmu->pgsize_bitmap |= SZ_4K | SZ_2M | SZ_1G;
/* Input address size */
- if (FIELD_GET(IDR5_VAX, reg) == IDR5_VAX_52_BIT)
+ if (FIELD_GET(IDR5_VAX, smmu->idr5) == IDR5_VAX_52_BIT)
smmu->features |= ARM_SMMU_FEAT_VAX;
/* Output address size */
- switch (FIELD_GET(IDR5_OAS, reg)) {
+ switch (FIELD_GET(IDR5_OAS, smmu->idr5)) {
case IDR5_OAS_32_BIT:
smmu->oas = 32;
break;
@@ -3632,6 +3638,16 @@ 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);
+
+ /* IDR6 */
+ smmu->idr6 = readl_relaxed(smmu->base + ARM_SMMU_IDR6);
+
+ /* IIDR */
+ smmu->iidr = readl_relaxed(smmu->base + ARM_SMMU_IIDR);
+
+ /* AIDR */
+ smmu->aidr = readl_relaxed(smmu->base + ARM_SMMU_AIDR);
+
return 0;
}
@@ -3752,6 +3768,119 @@ static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
return devm_ioremap_resource(dev, &res);
}
+static ssize_t smmu_idr0_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
+
+ return sprintf(buf, "%x\n", smmu->idr0);
+}
+static DEVICE_ATTR_RO(smmu_idr0);
+
+static ssize_t smmu_idr1_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
+
+ return sprintf(buf, "%x\n", smmu->idr1);
+}
+static DEVICE_ATTR_RO(smmu_idr1);
+
+static ssize_t smmu_idr2_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
+
+ return sprintf(buf, "%x\n", smmu->idr2);
+}
+static DEVICE_ATTR_RO(smmu_idr2);
+
+static ssize_t smmu_idr3_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
+
+ return sprintf(buf, "%x\n", smmu->idr3);
+}
+static DEVICE_ATTR_RO(smmu_idr3);
+
+static ssize_t smmu_idr4_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
+
+ return sprintf(buf, "%x\n", smmu->idr4);
+}
+static DEVICE_ATTR_RO(smmu_idr4);
+
+static ssize_t smmu_idr5_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
+
+ return sprintf(buf, "%x\n", smmu->idr5);
+}
+static DEVICE_ATTR_RO(smmu_idr5);
+
+static ssize_t smmu_idr6_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
+
+ return sprintf(buf, "%x\n", smmu->idr6);
+}
+static DEVICE_ATTR_RO(smmu_idr6);
+
+static ssize_t smmu_iidr_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
+
+ return sprintf(buf, "%x\n", smmu->iidr);
+}
+static DEVICE_ATTR_RO(smmu_iidr);
+
+static ssize_t smmu_aidr_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
+
+ return sprintf(buf, "%x\n", smmu->aidr);
+}
+static DEVICE_ATTR_RO(smmu_aidr);
+
+static struct attribute *arm_iommu_attrs[] = {
+ &dev_attr_smmu_idr0.attr,
+ &dev_attr_smmu_idr1.attr,
+ &dev_attr_smmu_idr2.attr,
+ &dev_attr_smmu_idr3.attr,
+ &dev_attr_smmu_idr4.attr,
+ &dev_attr_smmu_idr5.attr,
+ &dev_attr_smmu_idr6.attr,
+ &dev_attr_smmu_iidr.attr,
+ &dev_attr_smmu_aidr.attr,
+ NULL,
+};
+
+static struct attribute_group arm_iommu_group = {
+ .name = "arm-iommu",
+ .attrs = arm_iommu_attrs,
+};
+
+static const struct attribute_group *arm_iommu_groups[] = {
+ &arm_iommu_group,
+ NULL,
+};
+
static int arm_smmu_device_probe(struct platform_device *pdev)
{
int irq, ret;
@@ -3839,7 +3968,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
return ret;
/* And we're up. Go go go! */
- ret = iommu_device_sysfs_add(&smmu->iommu, dev, NULL,
+ ret = iommu_device_sysfs_add(&smmu->iommu, dev, arm_iommu_groups,
"smmu3.%pa", &ioaddr);
if (ret)
return ret;
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 cd48590ada30..ffa1123bf37c 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -50,9 +50,13 @@
#define IDR1_SSIDSIZE GENMASK(10, 6)
#define IDR1_SIDSIZE GENMASK(5, 0)
+#define ARM_SMMU_IDR2 0x8
+
#define ARM_SMMU_IDR3 0xc
#define IDR3_RIL (1 << 10)
+#define ARM_SMMU_IDR4 0x10
+
#define ARM_SMMU_IDR5 0x14
#define IDR5_STALL_MAX GENMASK(31, 16)
#define IDR5_GRAN64K (1 << 6)
@@ -69,6 +73,9 @@
#define IDR5_VAX GENMASK(11, 10)
#define IDR5_VAX_52_BIT 1
+#define ARM_SMMU_IIDR 0x18
+#define ARM_SMMU_AIDR 0x1C
+
#define ARM_SMMU_CR0 0x20
#define CR0_ATSCHK (1 << 4)
#define CR0_CMDQEN (1 << 3)
@@ -154,6 +161,8 @@
#define ARM_SMMU_REG_SZ 0xe00
+#define ARM_SMMU_IDR6 0x0190
+
/* Common MSI config fields */
#define MSI_CFG0_ADDR_MASK GENMASK_ULL(51, 2)
#define MSI_CFG2_SH GENMASK(5, 4)
@@ -669,6 +678,17 @@ struct arm_smmu_device {
struct arm_smmu_strtab_cfg strtab_cfg;
+ /* SMMU feature registers */
+ u32 idr0;
+ u32 idr1;
+ u32 idr2;
+ u32 idr3;
+ u32 idr4;
+ u32 idr5;
+ u32 idr6;
+ u32 iidr;
+ u32 aidr;
+
/* IOMMU core code handle */
struct iommu_device iommu;
@@ -676,6 +696,13 @@ struct arm_smmu_device {
struct mutex streams_mutex;
};
+static inline struct arm_smmu_device *dev_to_arm_smmu_device(struct device *dev)
+{
+ struct iommu_device *iommu = dev_to_iommu_device(dev);
+
+ return container_of(iommu, struct arm_smmu_device, iommu);
+}
+
struct arm_smmu_stream {
u32 id;
struct arm_smmu_master *master;
--
2.35.1
On 2022-03-23 12:54, Miguel Luis wrote:
> Allows userspace to check for SMMUv3 features.
What will userspace do with that information?
It hardly matters what fancy new features might be present, if the
kernel and/or the abstracted interfaces available to userspace aren't
using them. Any functionality which is supported by a usable interface
should ideally be represented via that interface itself.
Furthermore many of the raw SMMU features depend on other system
components and/or firmware, so the ID registers alone don't tell the
full story anyway.
> Expose the following RO registers related to ARM SMMUv3 via sysfs:
> SMMU_IDR0
> SMMU_IDR1
> SMMU_IDR2
> SMMU_IDR3
> SMMU_IDR4
> SMMU_IDR5
> SMMU_IDR6
> SMMU_IIDR
> SMMU_AIDR
>
> # find /sys | grep arm-iommu
> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu
Nit: my main comment above notwithstanding, is this level of hierarchcy
meaningful or useful? "arm-iommu" isn't an established name for anything
as far as I'm aware.
Robin.
> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr5
> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr3
> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr1
> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_aidr
> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr6
> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr4
> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_iidr
> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr2
> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr0
>
> Signed-off-by: Miguel Luis <[email protected]>
> ---
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 199 ++++++++++++++++----
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 27 +++
> 2 files changed, 191 insertions(+), 35 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 6dc6d8b6b368..7f779d3f88f2 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -3424,17 +3424,16 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
>
> static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> {
> - u32 reg;
> bool coherent = smmu->features & ARM_SMMU_FEAT_COHERENCY;
>
> /* IDR0 */
> - reg = readl_relaxed(smmu->base + ARM_SMMU_IDR0);
> + smmu->idr0 = readl_relaxed(smmu->base + ARM_SMMU_IDR0);
>
> /* 2-level structures */
> - if (FIELD_GET(IDR0_ST_LVL, reg) == IDR0_ST_LVL_2LVL)
> + if (FIELD_GET(IDR0_ST_LVL, smmu->idr0) == IDR0_ST_LVL_2LVL)
> smmu->features |= ARM_SMMU_FEAT_2_LVL_STRTAB;
>
> - if (reg & IDR0_CD2L)
> + if (smmu->idr0 & IDR0_CD2L)
> smmu->features |= ARM_SMMU_FEAT_2_LVL_CDTAB;
>
> /*
> @@ -3442,7 +3441,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> * We currently require the same endianness as the CPU, but this
> * could be changed later by adding a new IO_PGTABLE_QUIRK.
> */
> - switch (FIELD_GET(IDR0_TTENDIAN, reg)) {
> + switch (FIELD_GET(IDR0_TTENDIAN, smmu->idr0)) {
> case IDR0_TTENDIAN_MIXED:
> smmu->features |= ARM_SMMU_FEAT_TT_LE | ARM_SMMU_FEAT_TT_BE;
> break;
> @@ -3461,22 +3460,22 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> }
>
> /* Boolean feature flags */
> - if (IS_ENABLED(CONFIG_PCI_PRI) && reg & IDR0_PRI)
> + if (IS_ENABLED(CONFIG_PCI_PRI) && smmu->idr0 & IDR0_PRI)
> smmu->features |= ARM_SMMU_FEAT_PRI;
>
> - if (IS_ENABLED(CONFIG_PCI_ATS) && reg & IDR0_ATS)
> + if (IS_ENABLED(CONFIG_PCI_ATS) && smmu->idr0 & IDR0_ATS)
> smmu->features |= ARM_SMMU_FEAT_ATS;
>
> - if (reg & IDR0_SEV)
> + if (smmu->idr0 & IDR0_SEV)
> smmu->features |= ARM_SMMU_FEAT_SEV;
>
> - if (reg & IDR0_MSI) {
> + if (smmu->idr0 & IDR0_MSI) {
> smmu->features |= ARM_SMMU_FEAT_MSI;
> if (coherent && !disable_msipolling)
> smmu->options |= ARM_SMMU_OPT_MSIPOLL;
> }
>
> - if (reg & IDR0_HYP) {
> + if (smmu->idr0 & IDR0_HYP) {
> smmu->features |= ARM_SMMU_FEAT_HYP;
> if (cpus_have_cap(ARM64_HAS_VIRT_HOST_EXTN))
> smmu->features |= ARM_SMMU_FEAT_E2H;
> @@ -3486,11 +3485,11 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> * The coherency feature as set by FW is used in preference to the ID
> * register, but warn on mismatch.
> */
> - if (!!(reg & IDR0_COHACC) != coherent)
> + if (!!(smmu->idr0 & IDR0_COHACC) != coherent)
> dev_warn(smmu->dev, "IDR0.COHACC overridden by FW configuration (%s)\n",
> coherent ? "true" : "false");
>
> - switch (FIELD_GET(IDR0_STALL_MODEL, reg)) {
> + switch (FIELD_GET(IDR0_STALL_MODEL, smmu->idr0)) {
> case IDR0_STALL_MODEL_FORCE:
> smmu->features |= ARM_SMMU_FEAT_STALL_FORCE;
> fallthrough;
> @@ -3498,19 +3497,19 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> smmu->features |= ARM_SMMU_FEAT_STALLS;
> }
>
> - if (reg & IDR0_S1P)
> + if (smmu->idr0 & IDR0_S1P)
> smmu->features |= ARM_SMMU_FEAT_TRANS_S1;
>
> - if (reg & IDR0_S2P)
> + if (smmu->idr0 & IDR0_S2P)
> smmu->features |= ARM_SMMU_FEAT_TRANS_S2;
>
> - if (!(reg & (IDR0_S1P | IDR0_S2P))) {
> + if (!(smmu->idr0 & (IDR0_S1P | IDR0_S2P))) {
> dev_err(smmu->dev, "no translation support!\n");
> return -ENXIO;
> }
>
> /* We only support the AArch64 table format at present */
> - switch (FIELD_GET(IDR0_TTF, reg)) {
> + switch (FIELD_GET(IDR0_TTF, smmu->idr0)) {
> case IDR0_TTF_AARCH32_64:
> smmu->ias = 40;
> fallthrough;
> @@ -3522,19 +3521,20 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> }
>
> /* ASID/VMID sizes */
> - smmu->asid_bits = reg & IDR0_ASID16 ? 16 : 8;
> - smmu->vmid_bits = reg & IDR0_VMID16 ? 16 : 8;
> + smmu->asid_bits = smmu->idr0 & IDR0_ASID16 ? 16 : 8;
> + smmu->vmid_bits = smmu->idr0 & IDR0_VMID16 ? 16 : 8;
>
> /* IDR1 */
> - reg = readl_relaxed(smmu->base + ARM_SMMU_IDR1);
> - if (reg & (IDR1_TABLES_PRESET | IDR1_QUEUES_PRESET | IDR1_REL)) {
> + smmu->idr1 = readl_relaxed(smmu->base + ARM_SMMU_IDR1);
> +
> + if (smmu->idr1 & (IDR1_TABLES_PRESET | IDR1_QUEUES_PRESET | IDR1_REL)) {
> dev_err(smmu->dev, "embedded implementation not supported\n");
> return -ENXIO;
> }
>
> /* Queue sizes, capped to ensure natural alignment */
> smmu->cmdq.q.llq.max_n_shift = min_t(u32, CMDQ_MAX_SZ_SHIFT,
> - FIELD_GET(IDR1_CMDQS, reg));
> + FIELD_GET(IDR1_CMDQS, smmu->idr1));
> if (smmu->cmdq.q.llq.max_n_shift <= ilog2(CMDQ_BATCH_ENTRIES)) {
> /*
> * We don't support splitting up batches, so one batch of
> @@ -3548,13 +3548,13 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> }
>
> smmu->evtq.q.llq.max_n_shift = min_t(u32, EVTQ_MAX_SZ_SHIFT,
> - FIELD_GET(IDR1_EVTQS, reg));
> + FIELD_GET(IDR1_EVTQS, smmu->idr1));
> smmu->priq.q.llq.max_n_shift = min_t(u32, PRIQ_MAX_SZ_SHIFT,
> - FIELD_GET(IDR1_PRIQS, reg));
> + FIELD_GET(IDR1_PRIQS, smmu->idr1));
>
> /* SID/SSID sizes */
> - smmu->ssid_bits = FIELD_GET(IDR1_SSIDSIZE, reg);
> - smmu->sid_bits = FIELD_GET(IDR1_SIDSIZE, reg);
> + smmu->ssid_bits = FIELD_GET(IDR1_SSIDSIZE, smmu->idr1);
> + smmu->sid_bits = FIELD_GET(IDR1_SIDSIZE, smmu->idr1);
>
> /*
> * If the SMMU supports fewer bits than would fill a single L2 stream
> @@ -3563,31 +3563,37 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> if (smmu->sid_bits <= STRTAB_SPLIT)
> smmu->features &= ~ARM_SMMU_FEAT_2_LVL_STRTAB;
>
> + /* IDR2 */
> + smmu->idr2 = readl_relaxed(smmu->base + ARM_SMMU_IDR2);
> +
> /* IDR3 */
> - reg = readl_relaxed(smmu->base + ARM_SMMU_IDR3);
> - if (FIELD_GET(IDR3_RIL, reg))
> + smmu->idr3 = readl_relaxed(smmu->base + ARM_SMMU_IDR3);
> + if (FIELD_GET(IDR3_RIL, smmu->idr3))
> smmu->features |= ARM_SMMU_FEAT_RANGE_INV;
>
> + /* IDR4 */
> + smmu->idr4 = readl_relaxed(smmu->base + ARM_SMMU_IDR4);
> +
> /* IDR5 */
> - reg = readl_relaxed(smmu->base + ARM_SMMU_IDR5);
> + smmu->idr5 = readl_relaxed(smmu->base + ARM_SMMU_IDR5);
>
> /* Maximum number of outstanding stalls */
> - smmu->evtq.max_stalls = FIELD_GET(IDR5_STALL_MAX, reg);
> + smmu->evtq.max_stalls = FIELD_GET(IDR5_STALL_MAX, smmu->idr5);
>
> /* Page sizes */
> - if (reg & IDR5_GRAN64K)
> + if (smmu->idr5 & IDR5_GRAN64K)
> smmu->pgsize_bitmap |= SZ_64K | SZ_512M;
> - if (reg & IDR5_GRAN16K)
> + if (smmu->idr5 & IDR5_GRAN16K)
> smmu->pgsize_bitmap |= SZ_16K | SZ_32M;
> - if (reg & IDR5_GRAN4K)
> + if (smmu->idr5 & IDR5_GRAN4K)
> smmu->pgsize_bitmap |= SZ_4K | SZ_2M | SZ_1G;
>
> /* Input address size */
> - if (FIELD_GET(IDR5_VAX, reg) == IDR5_VAX_52_BIT)
> + if (FIELD_GET(IDR5_VAX, smmu->idr5) == IDR5_VAX_52_BIT)
> smmu->features |= ARM_SMMU_FEAT_VAX;
>
> /* Output address size */
> - switch (FIELD_GET(IDR5_OAS, reg)) {
> + switch (FIELD_GET(IDR5_OAS, smmu->idr5)) {
> case IDR5_OAS_32_BIT:
> smmu->oas = 32;
> break;
> @@ -3632,6 +3638,16 @@ 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);
> +
> + /* IDR6 */
> + smmu->idr6 = readl_relaxed(smmu->base + ARM_SMMU_IDR6);
> +
> + /* IIDR */
> + smmu->iidr = readl_relaxed(smmu->base + ARM_SMMU_IIDR);
> +
> + /* AIDR */
> + smmu->aidr = readl_relaxed(smmu->base + ARM_SMMU_AIDR);
> +
> return 0;
> }
>
> @@ -3752,6 +3768,119 @@ static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
> return devm_ioremap_resource(dev, &res);
> }
>
> +static ssize_t smmu_idr0_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
> +
> + return sprintf(buf, "%x\n", smmu->idr0);
> +}
> +static DEVICE_ATTR_RO(smmu_idr0);
> +
> +static ssize_t smmu_idr1_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
> +
> + return sprintf(buf, "%x\n", smmu->idr1);
> +}
> +static DEVICE_ATTR_RO(smmu_idr1);
> +
> +static ssize_t smmu_idr2_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
> +
> + return sprintf(buf, "%x\n", smmu->idr2);
> +}
> +static DEVICE_ATTR_RO(smmu_idr2);
> +
> +static ssize_t smmu_idr3_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
> +
> + return sprintf(buf, "%x\n", smmu->idr3);
> +}
> +static DEVICE_ATTR_RO(smmu_idr3);
> +
> +static ssize_t smmu_idr4_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
> +
> + return sprintf(buf, "%x\n", smmu->idr4);
> +}
> +static DEVICE_ATTR_RO(smmu_idr4);
> +
> +static ssize_t smmu_idr5_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
> +
> + return sprintf(buf, "%x\n", smmu->idr5);
> +}
> +static DEVICE_ATTR_RO(smmu_idr5);
> +
> +static ssize_t smmu_idr6_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
> +
> + return sprintf(buf, "%x\n", smmu->idr6);
> +}
> +static DEVICE_ATTR_RO(smmu_idr6);
> +
> +static ssize_t smmu_iidr_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
> +
> + return sprintf(buf, "%x\n", smmu->iidr);
> +}
> +static DEVICE_ATTR_RO(smmu_iidr);
> +
> +static ssize_t smmu_aidr_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
> +
> + return sprintf(buf, "%x\n", smmu->aidr);
> +}
> +static DEVICE_ATTR_RO(smmu_aidr);
> +
> +static struct attribute *arm_iommu_attrs[] = {
> + &dev_attr_smmu_idr0.attr,
> + &dev_attr_smmu_idr1.attr,
> + &dev_attr_smmu_idr2.attr,
> + &dev_attr_smmu_idr3.attr,
> + &dev_attr_smmu_idr4.attr,
> + &dev_attr_smmu_idr5.attr,
> + &dev_attr_smmu_idr6.attr,
> + &dev_attr_smmu_iidr.attr,
> + &dev_attr_smmu_aidr.attr,
> + NULL,
> +};
> +
> +static struct attribute_group arm_iommu_group = {
> + .name = "arm-iommu",
> + .attrs = arm_iommu_attrs,
> +};
> +
> +static const struct attribute_group *arm_iommu_groups[] = {
> + &arm_iommu_group,
> + NULL,
> +};
> +
> static int arm_smmu_device_probe(struct platform_device *pdev)
> {
> int irq, ret;
> @@ -3839,7 +3968,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
> return ret;
>
> /* And we're up. Go go go! */
> - ret = iommu_device_sysfs_add(&smmu->iommu, dev, NULL,
> + ret = iommu_device_sysfs_add(&smmu->iommu, dev, arm_iommu_groups,
> "smmu3.%pa", &ioaddr);
> if (ret)
> return ret;
> 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 cd48590ada30..ffa1123bf37c 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
> @@ -50,9 +50,13 @@
> #define IDR1_SSIDSIZE GENMASK(10, 6)
> #define IDR1_SIDSIZE GENMASK(5, 0)
>
> +#define ARM_SMMU_IDR2 0x8
> +
> #define ARM_SMMU_IDR3 0xc
> #define IDR3_RIL (1 << 10)
>
> +#define ARM_SMMU_IDR4 0x10
> +
> #define ARM_SMMU_IDR5 0x14
> #define IDR5_STALL_MAX GENMASK(31, 16)
> #define IDR5_GRAN64K (1 << 6)
> @@ -69,6 +73,9 @@
> #define IDR5_VAX GENMASK(11, 10)
> #define IDR5_VAX_52_BIT 1
>
> +#define ARM_SMMU_IIDR 0x18
> +#define ARM_SMMU_AIDR 0x1C
> +
> #define ARM_SMMU_CR0 0x20
> #define CR0_ATSCHK (1 << 4)
> #define CR0_CMDQEN (1 << 3)
> @@ -154,6 +161,8 @@
>
> #define ARM_SMMU_REG_SZ 0xe00
>
> +#define ARM_SMMU_IDR6 0x0190
> +
> /* Common MSI config fields */
> #define MSI_CFG0_ADDR_MASK GENMASK_ULL(51, 2)
> #define MSI_CFG2_SH GENMASK(5, 4)
> @@ -669,6 +678,17 @@ struct arm_smmu_device {
>
> struct arm_smmu_strtab_cfg strtab_cfg;
>
> + /* SMMU feature registers */
> + u32 idr0;
> + u32 idr1;
> + u32 idr2;
> + u32 idr3;
> + u32 idr4;
> + u32 idr5;
> + u32 idr6;
> + u32 iidr;
> + u32 aidr;
> +
> /* IOMMU core code handle */
> struct iommu_device iommu;
>
> @@ -676,6 +696,13 @@ struct arm_smmu_device {
> struct mutex streams_mutex;
> };
>
> +static inline struct arm_smmu_device *dev_to_arm_smmu_device(struct device *dev)
> +{
> + struct iommu_device *iommu = dev_to_iommu_device(dev);
> +
> + return container_of(iommu, struct arm_smmu_device, iommu);
> +}
> +
> struct arm_smmu_stream {
> u32 id;
> struct arm_smmu_master *master;
> On 23 Mar 2022, at 12:40, Robin Murphy <[email protected]> wrote:
>
> On 2022-03-23 12:54, Miguel Luis wrote:
>> Allows userspace to check for SMMUv3 features.
>
> What will userspace do with that information?
>
> It hardly matters what fancy new features might be present, if the kernel and/or the abstracted interfaces available to userspace aren't using them. Any functionality which is supported by a usable interface should ideally be represented via that interface itself.
>
The inspiration was the same that Intel (cap/ecap) and AMD (cap/features) took
exposing it's iommu feature registers on sysfs. It's an easy way to understand
which features are supported by the hardware regardless of what the kernel
supports.
For example I could print the smmu->features and that would cover kernel
supported features but wouldn't help when new hardware arrives to know which
features are supported by the hardware.
> Furthermore many of the raw SMMU features depend on other system components and/or firmware, so the ID registers alone don't tell the full story anyway.
>
Would you mind to elaborate a bit more on that please? Would that mean that if a
feature bit is set it doesn’t really tell that the feature is supported?
>> Expose the following RO registers related to ARM SMMUv3 via sysfs:
>> SMMU_IDR0
>> SMMU_IDR1
>> SMMU_IDR2
>> SMMU_IDR3
>> SMMU_IDR4
>> SMMU_IDR5
>> SMMU_IDR6
>> SMMU_IIDR
>> SMMU_AIDR
>> # find /sys | grep arm-iommu
>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu
>
> Nit: my main comment above notwithstanding, is this level of hierarchcy meaningful or useful? "arm-iommu" isn't an established name for anything as far as I'm aware.
>
I've followed the existent convention in other IOMMUs but I'm totally open
to alternatives/suggestions.
Miguel
> Robin.
>
>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr5
>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr3
>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr1
>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_aidr
>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr6
>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr4
>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_iidr
>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr2
>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr0
>> Signed-off-by: Miguel Luis <[email protected]>
>> ---
>> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 199 ++++++++++++++++----
>> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 27 +++
>> 2 files changed, 191 insertions(+), 35 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 6dc6d8b6b368..7f779d3f88f2 100644
>> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>> @@ -3424,17 +3424,16 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
>> static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>> {
>> - u32 reg;
>> bool coherent = smmu->features & ARM_SMMU_FEAT_COHERENCY;
>> /* IDR0 */
>> - reg = readl_relaxed(smmu->base + ARM_SMMU_IDR0);
>> + smmu->idr0 = readl_relaxed(smmu->base + ARM_SMMU_IDR0);
>> /* 2-level structures */
>> - if (FIELD_GET(IDR0_ST_LVL, reg) == IDR0_ST_LVL_2LVL)
>> + if (FIELD_GET(IDR0_ST_LVL, smmu->idr0) == IDR0_ST_LVL_2LVL)
>> smmu->features |= ARM_SMMU_FEAT_2_LVL_STRTAB;
>> - if (reg & IDR0_CD2L)
>> + if (smmu->idr0 & IDR0_CD2L)
>> smmu->features |= ARM_SMMU_FEAT_2_LVL_CDTAB;
>> /*
>> @@ -3442,7 +3441,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>> * We currently require the same endianness as the CPU, but this
>> * could be changed later by adding a new IO_PGTABLE_QUIRK.
>> */
>> - switch (FIELD_GET(IDR0_TTENDIAN, reg)) {
>> + switch (FIELD_GET(IDR0_TTENDIAN, smmu->idr0)) {
>> case IDR0_TTENDIAN_MIXED:
>> smmu->features |= ARM_SMMU_FEAT_TT_LE | ARM_SMMU_FEAT_TT_BE;
>> break;
>> @@ -3461,22 +3460,22 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>> }
>> /* Boolean feature flags */
>> - if (IS_ENABLED(CONFIG_PCI_PRI) && reg & IDR0_PRI)
>> + if (IS_ENABLED(CONFIG_PCI_PRI) && smmu->idr0 & IDR0_PRI)
>> smmu->features |= ARM_SMMU_FEAT_PRI;
>> - if (IS_ENABLED(CONFIG_PCI_ATS) && reg & IDR0_ATS)
>> + if (IS_ENABLED(CONFIG_PCI_ATS) && smmu->idr0 & IDR0_ATS)
>> smmu->features |= ARM_SMMU_FEAT_ATS;
>> - if (reg & IDR0_SEV)
>> + if (smmu->idr0 & IDR0_SEV)
>> smmu->features |= ARM_SMMU_FEAT_SEV;
>> - if (reg & IDR0_MSI) {
>> + if (smmu->idr0 & IDR0_MSI) {
>> smmu->features |= ARM_SMMU_FEAT_MSI;
>> if (coherent && !disable_msipolling)
>> smmu->options |= ARM_SMMU_OPT_MSIPOLL;
>> }
>> - if (reg & IDR0_HYP) {
>> + if (smmu->idr0 & IDR0_HYP) {
>> smmu->features |= ARM_SMMU_FEAT_HYP;
>> if (cpus_have_cap(ARM64_HAS_VIRT_HOST_EXTN))
>> smmu->features |= ARM_SMMU_FEAT_E2H;
>> @@ -3486,11 +3485,11 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>> * The coherency feature as set by FW is used in preference to the ID
>> * register, but warn on mismatch.
>> */
>> - if (!!(reg & IDR0_COHACC) != coherent)
>> + if (!!(smmu->idr0 & IDR0_COHACC) != coherent)
>> dev_warn(smmu->dev, "IDR0.COHACC overridden by FW configuration (%s)\n",
>> coherent ? "true" : "false");
>> - switch (FIELD_GET(IDR0_STALL_MODEL, reg)) {
>> + switch (FIELD_GET(IDR0_STALL_MODEL, smmu->idr0)) {
>> case IDR0_STALL_MODEL_FORCE:
>> smmu->features |= ARM_SMMU_FEAT_STALL_FORCE;
>> fallthrough;
>> @@ -3498,19 +3497,19 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>> smmu->features |= ARM_SMMU_FEAT_STALLS;
>> }
>> - if (reg & IDR0_S1P)
>> + if (smmu->idr0 & IDR0_S1P)
>> smmu->features |= ARM_SMMU_FEAT_TRANS_S1;
>> - if (reg & IDR0_S2P)
>> + if (smmu->idr0 & IDR0_S2P)
>> smmu->features |= ARM_SMMU_FEAT_TRANS_S2;
>> - if (!(reg & (IDR0_S1P | IDR0_S2P))) {
>> + if (!(smmu->idr0 & (IDR0_S1P | IDR0_S2P))) {
>> dev_err(smmu->dev, "no translation support!\n");
>> return -ENXIO;
>> }
>> /* We only support the AArch64 table format at present */
>> - switch (FIELD_GET(IDR0_TTF, reg)) {
>> + switch (FIELD_GET(IDR0_TTF, smmu->idr0)) {
>> case IDR0_TTF_AARCH32_64:
>> smmu->ias = 40;
>> fallthrough;
>> @@ -3522,19 +3521,20 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>> }
>> /* ASID/VMID sizes */
>> - smmu->asid_bits = reg & IDR0_ASID16 ? 16 : 8;
>> - smmu->vmid_bits = reg & IDR0_VMID16 ? 16 : 8;
>> + smmu->asid_bits = smmu->idr0 & IDR0_ASID16 ? 16 : 8;
>> + smmu->vmid_bits = smmu->idr0 & IDR0_VMID16 ? 16 : 8;
>> /* IDR1 */
>> - reg = readl_relaxed(smmu->base + ARM_SMMU_IDR1);
>> - if (reg & (IDR1_TABLES_PRESET | IDR1_QUEUES_PRESET | IDR1_REL)) {
>> + smmu->idr1 = readl_relaxed(smmu->base + ARM_SMMU_IDR1);
>> +
>> + if (smmu->idr1 & (IDR1_TABLES_PRESET | IDR1_QUEUES_PRESET | IDR1_REL)) {
>> dev_err(smmu->dev, "embedded implementation not supported\n");
>> return -ENXIO;
>> }
>> /* Queue sizes, capped to ensure natural alignment */
>> smmu->cmdq.q.llq.max_n_shift = min_t(u32, CMDQ_MAX_SZ_SHIFT,
>> - FIELD_GET(IDR1_CMDQS, reg));
>> + FIELD_GET(IDR1_CMDQS, smmu->idr1));
>> if (smmu->cmdq.q.llq.max_n_shift <= ilog2(CMDQ_BATCH_ENTRIES)) {
>> /*
>> * We don't support splitting up batches, so one batch of
>> @@ -3548,13 +3548,13 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>> }
>> smmu->evtq.q.llq.max_n_shift = min_t(u32, EVTQ_MAX_SZ_SHIFT,
>> - FIELD_GET(IDR1_EVTQS, reg));
>> + FIELD_GET(IDR1_EVTQS, smmu->idr1));
>> smmu->priq.q.llq.max_n_shift = min_t(u32, PRIQ_MAX_SZ_SHIFT,
>> - FIELD_GET(IDR1_PRIQS, reg));
>> + FIELD_GET(IDR1_PRIQS, smmu->idr1));
>> /* SID/SSID sizes */
>> - smmu->ssid_bits = FIELD_GET(IDR1_SSIDSIZE, reg);
>> - smmu->sid_bits = FIELD_GET(IDR1_SIDSIZE, reg);
>> + smmu->ssid_bits = FIELD_GET(IDR1_SSIDSIZE, smmu->idr1);
>> + smmu->sid_bits = FIELD_GET(IDR1_SIDSIZE, smmu->idr1);
>> /*
>> * If the SMMU supports fewer bits than would fill a single L2 stream
>> @@ -3563,31 +3563,37 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>> if (smmu->sid_bits <= STRTAB_SPLIT)
>> smmu->features &= ~ARM_SMMU_FEAT_2_LVL_STRTAB;
>> + /* IDR2 */
>> + smmu->idr2 = readl_relaxed(smmu->base + ARM_SMMU_IDR2);
>> +
>> /* IDR3 */
>> - reg = readl_relaxed(smmu->base + ARM_SMMU_IDR3);
>> - if (FIELD_GET(IDR3_RIL, reg))
>> + smmu->idr3 = readl_relaxed(smmu->base + ARM_SMMU_IDR3);
>> + if (FIELD_GET(IDR3_RIL, smmu->idr3))
>> smmu->features |= ARM_SMMU_FEAT_RANGE_INV;
>> + /* IDR4 */
>> + smmu->idr4 = readl_relaxed(smmu->base + ARM_SMMU_IDR4);
>> +
>> /* IDR5 */
>> - reg = readl_relaxed(smmu->base + ARM_SMMU_IDR5);
>> + smmu->idr5 = readl_relaxed(smmu->base + ARM_SMMU_IDR5);
>> /* Maximum number of outstanding stalls */
>> - smmu->evtq.max_stalls = FIELD_GET(IDR5_STALL_MAX, reg);
>> + smmu->evtq.max_stalls = FIELD_GET(IDR5_STALL_MAX, smmu->idr5);
>> /* Page sizes */
>> - if (reg & IDR5_GRAN64K)
>> + if (smmu->idr5 & IDR5_GRAN64K)
>> smmu->pgsize_bitmap |= SZ_64K | SZ_512M;
>> - if (reg & IDR5_GRAN16K)
>> + if (smmu->idr5 & IDR5_GRAN16K)
>> smmu->pgsize_bitmap |= SZ_16K | SZ_32M;
>> - if (reg & IDR5_GRAN4K)
>> + if (smmu->idr5 & IDR5_GRAN4K)
>> smmu->pgsize_bitmap |= SZ_4K | SZ_2M | SZ_1G;
>> /* Input address size */
>> - if (FIELD_GET(IDR5_VAX, reg) == IDR5_VAX_52_BIT)
>> + if (FIELD_GET(IDR5_VAX, smmu->idr5) == IDR5_VAX_52_BIT)
>> smmu->features |= ARM_SMMU_FEAT_VAX;
>> /* Output address size */
>> - switch (FIELD_GET(IDR5_OAS, reg)) {
>> + switch (FIELD_GET(IDR5_OAS, smmu->idr5)) {
>> case IDR5_OAS_32_BIT:
>> smmu->oas = 32;
>> break;
>> @@ -3632,6 +3638,16 @@ 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);
>> +
>> + /* IDR6 */
>> + smmu->idr6 = readl_relaxed(smmu->base + ARM_SMMU_IDR6);
>> +
>> + /* IIDR */
>> + smmu->iidr = readl_relaxed(smmu->base + ARM_SMMU_IIDR);
>> +
>> + /* AIDR */
>> + smmu->aidr = readl_relaxed(smmu->base + ARM_SMMU_AIDR);
>> +
>> return 0;
>> }
>> @@ -3752,6 +3768,119 @@ static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
>> return devm_ioremap_resource(dev, &res);
>> }
>> +static ssize_t smmu_idr0_show(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>> +
>> + return sprintf(buf, "%x\n", smmu->idr0);
>> +}
>> +static DEVICE_ATTR_RO(smmu_idr0);
>> +
>> +static ssize_t smmu_idr1_show(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>> +
>> + return sprintf(buf, "%x\n", smmu->idr1);
>> +}
>> +static DEVICE_ATTR_RO(smmu_idr1);
>> +
>> +static ssize_t smmu_idr2_show(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>> +
>> + return sprintf(buf, "%x\n", smmu->idr2);
>> +}
>> +static DEVICE_ATTR_RO(smmu_idr2);
>> +
>> +static ssize_t smmu_idr3_show(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>> +
>> + return sprintf(buf, "%x\n", smmu->idr3);
>> +}
>> +static DEVICE_ATTR_RO(smmu_idr3);
>> +
>> +static ssize_t smmu_idr4_show(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>> +
>> + return sprintf(buf, "%x\n", smmu->idr4);
>> +}
>> +static DEVICE_ATTR_RO(smmu_idr4);
>> +
>> +static ssize_t smmu_idr5_show(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>> +
>> + return sprintf(buf, "%x\n", smmu->idr5);
>> +}
>> +static DEVICE_ATTR_RO(smmu_idr5);
>> +
>> +static ssize_t smmu_idr6_show(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>> +
>> + return sprintf(buf, "%x\n", smmu->idr6);
>> +}
>> +static DEVICE_ATTR_RO(smmu_idr6);
>> +
>> +static ssize_t smmu_iidr_show(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>> +
>> + return sprintf(buf, "%x\n", smmu->iidr);
>> +}
>> +static DEVICE_ATTR_RO(smmu_iidr);
>> +
>> +static ssize_t smmu_aidr_show(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>> +
>> + return sprintf(buf, "%x\n", smmu->aidr);
>> +}
>> +static DEVICE_ATTR_RO(smmu_aidr);
>> +
>> +static struct attribute *arm_iommu_attrs[] = {
>> + &dev_attr_smmu_idr0.attr,
>> + &dev_attr_smmu_idr1.attr,
>> + &dev_attr_smmu_idr2.attr,
>> + &dev_attr_smmu_idr3.attr,
>> + &dev_attr_smmu_idr4.attr,
>> + &dev_attr_smmu_idr5.attr,
>> + &dev_attr_smmu_idr6.attr,
>> + &dev_attr_smmu_iidr.attr,
>> + &dev_attr_smmu_aidr.attr,
>> + NULL,
>> +};
>> +
>> +static struct attribute_group arm_iommu_group = {
>> + .name = "arm-iommu",
>> + .attrs = arm_iommu_attrs,
>> +};
>> +
>> +static const struct attribute_group *arm_iommu_groups[] = {
>> + &arm_iommu_group,
>> + NULL,
>> +};
>> +
>> static int arm_smmu_device_probe(struct platform_device *pdev)
>> {
>> int irq, ret;
>> @@ -3839,7 +3968,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
>> return ret;
>> /* And we're up. Go go go! */
>> - ret = iommu_device_sysfs_add(&smmu->iommu, dev, NULL,
>> + ret = iommu_device_sysfs_add(&smmu->iommu, dev, arm_iommu_groups,
>> "smmu3.%pa", &ioaddr);
>> if (ret)
>> return ret;
>> 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 cd48590ada30..ffa1123bf37c 100644
>> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
>> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
>> @@ -50,9 +50,13 @@
>> #define IDR1_SSIDSIZE GENMASK(10, 6)
>> #define IDR1_SIDSIZE GENMASK(5, 0)
>> +#define ARM_SMMU_IDR2 0x8
>> +
>> #define ARM_SMMU_IDR3 0xc
>> #define IDR3_RIL (1 << 10)
>> +#define ARM_SMMU_IDR4 0x10
>> +
>> #define ARM_SMMU_IDR5 0x14
>> #define IDR5_STALL_MAX GENMASK(31, 16)
>> #define IDR5_GRAN64K (1 << 6)
>> @@ -69,6 +73,9 @@
>> #define IDR5_VAX GENMASK(11, 10)
>> #define IDR5_VAX_52_BIT 1
>> +#define ARM_SMMU_IIDR 0x18
>> +#define ARM_SMMU_AIDR 0x1C
>> +
>> #define ARM_SMMU_CR0 0x20
>> #define CR0_ATSCHK (1 << 4)
>> #define CR0_CMDQEN (1 << 3)
>> @@ -154,6 +161,8 @@
>> #define ARM_SMMU_REG_SZ 0xe00
>> +#define ARM_SMMU_IDR6 0x0190
>> +
>> /* Common MSI config fields */
>> #define MSI_CFG0_ADDR_MASK GENMASK_ULL(51, 2)
>> #define MSI_CFG2_SH GENMASK(5, 4)
>> @@ -669,6 +678,17 @@ struct arm_smmu_device {
>> struct arm_smmu_strtab_cfg strtab_cfg;
>> + /* SMMU feature registers */
>> + u32 idr0;
>> + u32 idr1;
>> + u32 idr2;
>> + u32 idr3;
>> + u32 idr4;
>> + u32 idr5;
>> + u32 idr6;
>> + u32 iidr;
>> + u32 aidr;
>> +
>> /* IOMMU core code handle */
>> struct iommu_device iommu;
>> @@ -676,6 +696,13 @@ struct arm_smmu_device {
>> struct mutex streams_mutex;
>> };
>> +static inline struct arm_smmu_device *dev_to_arm_smmu_device(struct device *dev)
>> +{
>> + struct iommu_device *iommu = dev_to_iommu_device(dev);
>> +
>> + return container_of(iommu, struct arm_smmu_device, iommu);
>> +}
>> +
>> struct arm_smmu_stream {
>> u32 id;
>> struct arm_smmu_master *master;
On 3/25/22 18:03, Robin Murphy wrote:
> On 2022-03-23 15:09, Miguel Luis wrote:
>>> On 23 Mar 2022, at 12:40, Robin Murphy <[email protected]> wrote:
>>> On 2022-03-23 12:54, Miguel Luis wrote:
>>>> Allows userspace to check for SMMUv3 features.
>>>
>>> What will userspace do with that information?
>>>
>>> It hardly matters what fancy new features might be present, if the kernel and/or the abstracted interfaces available to userspace aren't using them. Any functionality which is supported by a usable interface should ideally be represented via that interface itself.
>>>
>>
>> The inspiration was the same that Intel (cap/ecap) and AMD (cap/features) took
>> exposing it's iommu feature registers on sysfs. It's an easy way to understand
>> which features are supported by the hardware regardless of what the kernel
>> supports.
>
> OK, so what do end-users of Intel and AMD systems do with that
> understanding then?
>
It's features probing and informational purposes really -- that's all
one can do with these registers regardless of IOMMU implementation.
There some others which print the version of the iommu that also appear
as RO sysfs entries.
Those two registers on those two implementations have proved useful the
last couple of years when I got new SDPs/machines.
At the end of the day some tool (or script) pretty prints what's
supported.. on what usually is depicted in very lenghty manuals.
And that's fed into a toolbox that prints all hardware and software
capabilities alongside diagnostics / etc (for troubleshooting).
You know, similar to `cpuid` on the x86 cpuid side (albeit you could
argue that it's behind a 'special' instruction). And that 'decodes' to
an human-friendly on what goes in those lenghty SDMs. `/proc/cpuinfo`
translates that into a set of keywords (which may be software-specific or
hardware features). And more recently `kcpuid` for raw-supported
features. I am sure there's more examples.
>> For example I could print the smmu->features and that would cover kernel
>> supported features but wouldn't help when new hardware arrives to know which
>> features are supported by the hardware.
>
> Indeed the driver already prints the supported features at boot, largely
> because it's useful for debugging. But again, what's the advantage of
> knowing what you might theoretically be able to do with a machine if you
> don't have the software support to actually do it? Are there users out
> there who aren't going to update their OS *unless* they can cling to the
> hope that a new OS might see the opportunity to use foreign-endianness
> pagetables and finally take it?
>
> I appreciate the natural human instinct to want to poke around at and
> evaluate a new shiny thing, but a sufficiently interested user can
> already do that with /dev/mem or any number of other ways. We don't need
> the burden of maintaining an upstream sysfs ABI for curiosity.
>
/dev/mem is an interesting alternative -- I wasn't quite sure you could use
the register addresses here arbitrarily on ARM. Anyways, I suppose it's an
worthwhile alternative in case it works.
> The other fact of the matter is that a great deal of systems with SMMUv3
> will be using one of Arm Ltd's implementations, and as soon as one knows
> that one can readily look up all the details in Arm's documentation.
> Especially when one already has that site open to find the SMMUv3
> architecture spec to make sense of cryptic register dumps, right?
>
Heh, the idea was to avoid going to those specs all the time, but I understand
your earlier point(s).
Also, IOMMUs are getting bigger in terms of featureset -- so it would be nice to
better introspect what iommus can do (in the whatever mix of implementations)
in a less chaotic manner. Maybe implementation-specific sysfs entries are not it,
but hopefully something else in a more generic-way, in the advent of a more
direct interface to iommus.
On 2022-03-23 15:09, Miguel Luis wrote:
>
>
>> On 23 Mar 2022, at 12:40, Robin Murphy <[email protected]> wrote:
>>
>> On 2022-03-23 12:54, Miguel Luis wrote:
>>> Allows userspace to check for SMMUv3 features.
>>
>> What will userspace do with that information?
>>
>> It hardly matters what fancy new features might be present, if the kernel and/or the abstracted interfaces available to userspace aren't using them. Any functionality which is supported by a usable interface should ideally be represented via that interface itself.
>>
>
> The inspiration was the same that Intel (cap/ecap) and AMD (cap/features) took
> exposing it's iommu feature registers on sysfs. It's an easy way to understand
> which features are supported by the hardware regardless of what the kernel
> supports.
OK, so what do end-users of Intel and AMD systems do with that
understanding then?
> For example I could print the smmu->features and that would cover kernel
> supported features but wouldn't help when new hardware arrives to know which
> features are supported by the hardware.
Indeed the driver already prints the supported features at boot, largely
because it's useful for debugging. But again, what's the advantage of
knowing what you might theoretically be able to do with a machine if you
don't have the software support to actually do it? Are there users out
there who aren't going to update their OS *unless* they can cling to the
hope that a new OS might see the opportunity to use foreign-endianness
pagetables and finally take it?
I appreciate the natural human instinct to want to poke around at and
evaluate a new shiny thing, but a sufficiently interested user can
already do that with /dev/mem or any number of other ways. We don't need
the burden of maintaining an upstream sysfs ABI for curiosity.
The other fact of the matter is that a great deal of systems with SMMUv3
will be using one of Arm Ltd's implementations, and as soon as one knows
that one can readily look up all the details in Arm's documentation.
Especially when one already has that site open to find the SMMUv3
architecture spec to make sense of cryptic register dumps, right?
>> Furthermore many of the raw SMMU features depend on other system components and/or firmware, so the ID registers alone don't tell the full story anyway.
>>
>
> Would you mind to elaborate a bit more on that please? Would that mean that if a
> feature bit is set it doesn’t really tell that the feature is supported?
Yes, Let's take some features of Arm's MMU-600 implementation as examples:
https://developer.arm.com/documentation/100310/0202/Functional-description/Constraints-and-limitations-of-use/SMMUv3-support
- MMU-600 supports ATS and PRI. Whether or not a given MMU-600 can ever
actually recieve any ATS or PRI requests depends on whether it's wired
up to a PCIe root complex capable of sending them.
- MMU-600 supports 20-bit SubstreamIDs (PASIDs), since that represents
the maximum size of context table it can index. How many of those bits
are actually capable of being driven by endpoints and/or carried across
interconnects depends on those respective components, and isn't
MMU-600's concern.
- MMU-600 supports stalling faults. Whether having a stalled transaction
sat across the interconnect might lead to a deadlock with transactions
attempting to load data to resolve the fault is the interconnect's problem.
- If the integrator correctly wires up the "evento" signal and sets the
"sup_sev" configuration tie-off, MMU-600 supports the SEV feature to
send wake-up events to waiting CPUs. Except early revisions have an
erratum where sometimes they'll miss sending an event, so software had
better knmow to cross-check SMMU_IIDR before trusting it.
- Similarly, it's not unheard of for integrators to set configuration
tie-offs incorrectly, or find issues after the fact which mean that
features like COHACC and BTM are broken. Therefore in practice those are
effectively ignored in favour of firmware overrides.
Note that on AMD at least, most of the reported features are actually
firmware overrides as well. However the main thing is that Intel and AMD
design and implement their IOMMU alongside their PCIe implementation and
everything else and only sell you the whole combination, so features
there can be inherently more joined-up than the building-block nature of
typical Arm-based systems allows. Chasing apparent parity for the sake
of it where a sufficient level of parity just doesn't exist is a waste
of time (see also: endless /proc/cpuinfo nonsense). You can paint a
baseball orange but it's still never going to be nice to eat.
Thanks,
Robin.
>>> Expose the following RO registers related to ARM SMMUv3 via sysfs:
>>> SMMU_IDR0
>>> SMMU_IDR1
>>> SMMU_IDR2
>>> SMMU_IDR3
>>> SMMU_IDR4
>>> SMMU_IDR5
>>> SMMU_IDR6
>>> SMMU_IIDR
>>> SMMU_AIDR
>>> # find /sys | grep arm-iommu
>>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu
>>
>> Nit: my main comment above notwithstanding, is this level of hierarchcy meaningful or useful? "arm-iommu" isn't an established name for anything as far as I'm aware.
>>
>
> I've followed the existent convention in other IOMMUs but I'm totally open
> to alternatives/suggestions.
>
> Miguel
>
>> Robin.
>>
>>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr5
>>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr3
>>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr1
>>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_aidr
>>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr6
>>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr4
>>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_iidr
>>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr2
>>> /sys/devices/platform/9050000.smmuv3/iommu/smmu3.0x0000000009050000/arm-iommu/smmu_idr0
>>> Signed-off-by: Miguel Luis <[email protected]>
>>> ---
>>> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 199 ++++++++++++++++----
>>> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 27 +++
>>> 2 files changed, 191 insertions(+), 35 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 6dc6d8b6b368..7f779d3f88f2 100644
>>> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>>> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>>> @@ -3424,17 +3424,16 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
>>> static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>>> {
>>> - u32 reg;
>>> bool coherent = smmu->features & ARM_SMMU_FEAT_COHERENCY;
>>> /* IDR0 */
>>> - reg = readl_relaxed(smmu->base + ARM_SMMU_IDR0);
>>> + smmu->idr0 = readl_relaxed(smmu->base + ARM_SMMU_IDR0);
>>> /* 2-level structures */
>>> - if (FIELD_GET(IDR0_ST_LVL, reg) == IDR0_ST_LVL_2LVL)
>>> + if (FIELD_GET(IDR0_ST_LVL, smmu->idr0) == IDR0_ST_LVL_2LVL)
>>> smmu->features |= ARM_SMMU_FEAT_2_LVL_STRTAB;
>>> - if (reg & IDR0_CD2L)
>>> + if (smmu->idr0 & IDR0_CD2L)
>>> smmu->features |= ARM_SMMU_FEAT_2_LVL_CDTAB;
>>> /*
>>> @@ -3442,7 +3441,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>>> * We currently require the same endianness as the CPU, but this
>>> * could be changed later by adding a new IO_PGTABLE_QUIRK.
>>> */
>>> - switch (FIELD_GET(IDR0_TTENDIAN, reg)) {
>>> + switch (FIELD_GET(IDR0_TTENDIAN, smmu->idr0)) {
>>> case IDR0_TTENDIAN_MIXED:
>>> smmu->features |= ARM_SMMU_FEAT_TT_LE | ARM_SMMU_FEAT_TT_BE;
>>> break;
>>> @@ -3461,22 +3460,22 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>>> }
>>> /* Boolean feature flags */
>>> - if (IS_ENABLED(CONFIG_PCI_PRI) && reg & IDR0_PRI)
>>> + if (IS_ENABLED(CONFIG_PCI_PRI) && smmu->idr0 & IDR0_PRI)
>>> smmu->features |= ARM_SMMU_FEAT_PRI;
>>> - if (IS_ENABLED(CONFIG_PCI_ATS) && reg & IDR0_ATS)
>>> + if (IS_ENABLED(CONFIG_PCI_ATS) && smmu->idr0 & IDR0_ATS)
>>> smmu->features |= ARM_SMMU_FEAT_ATS;
>>> - if (reg & IDR0_SEV)
>>> + if (smmu->idr0 & IDR0_SEV)
>>> smmu->features |= ARM_SMMU_FEAT_SEV;
>>> - if (reg & IDR0_MSI) {
>>> + if (smmu->idr0 & IDR0_MSI) {
>>> smmu->features |= ARM_SMMU_FEAT_MSI;
>>> if (coherent && !disable_msipolling)
>>> smmu->options |= ARM_SMMU_OPT_MSIPOLL;
>>> }
>>> - if (reg & IDR0_HYP) {
>>> + if (smmu->idr0 & IDR0_HYP) {
>>> smmu->features |= ARM_SMMU_FEAT_HYP;
>>> if (cpus_have_cap(ARM64_HAS_VIRT_HOST_EXTN))
>>> smmu->features |= ARM_SMMU_FEAT_E2H;
>>> @@ -3486,11 +3485,11 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>>> * The coherency feature as set by FW is used in preference to the ID
>>> * register, but warn on mismatch.
>>> */
>>> - if (!!(reg & IDR0_COHACC) != coherent)
>>> + if (!!(smmu->idr0 & IDR0_COHACC) != coherent)
>>> dev_warn(smmu->dev, "IDR0.COHACC overridden by FW configuration (%s)\n",
>>> coherent ? "true" : "false");
>>> - switch (FIELD_GET(IDR0_STALL_MODEL, reg)) {
>>> + switch (FIELD_GET(IDR0_STALL_MODEL, smmu->idr0)) {
>>> case IDR0_STALL_MODEL_FORCE:
>>> smmu->features |= ARM_SMMU_FEAT_STALL_FORCE;
>>> fallthrough;
>>> @@ -3498,19 +3497,19 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>>> smmu->features |= ARM_SMMU_FEAT_STALLS;
>>> }
>>> - if (reg & IDR0_S1P)
>>> + if (smmu->idr0 & IDR0_S1P)
>>> smmu->features |= ARM_SMMU_FEAT_TRANS_S1;
>>> - if (reg & IDR0_S2P)
>>> + if (smmu->idr0 & IDR0_S2P)
>>> smmu->features |= ARM_SMMU_FEAT_TRANS_S2;
>>> - if (!(reg & (IDR0_S1P | IDR0_S2P))) {
>>> + if (!(smmu->idr0 & (IDR0_S1P | IDR0_S2P))) {
>>> dev_err(smmu->dev, "no translation support!\n");
>>> return -ENXIO;
>>> }
>>> /* We only support the AArch64 table format at present */
>>> - switch (FIELD_GET(IDR0_TTF, reg)) {
>>> + switch (FIELD_GET(IDR0_TTF, smmu->idr0)) {
>>> case IDR0_TTF_AARCH32_64:
>>> smmu->ias = 40;
>>> fallthrough;
>>> @@ -3522,19 +3521,20 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>>> }
>>> /* ASID/VMID sizes */
>>> - smmu->asid_bits = reg & IDR0_ASID16 ? 16 : 8;
>>> - smmu->vmid_bits = reg & IDR0_VMID16 ? 16 : 8;
>>> + smmu->asid_bits = smmu->idr0 & IDR0_ASID16 ? 16 : 8;
>>> + smmu->vmid_bits = smmu->idr0 & IDR0_VMID16 ? 16 : 8;
>>> /* IDR1 */
>>> - reg = readl_relaxed(smmu->base + ARM_SMMU_IDR1);
>>> - if (reg & (IDR1_TABLES_PRESET | IDR1_QUEUES_PRESET | IDR1_REL)) {
>>> + smmu->idr1 = readl_relaxed(smmu->base + ARM_SMMU_IDR1);
>>> +
>>> + if (smmu->idr1 & (IDR1_TABLES_PRESET | IDR1_QUEUES_PRESET | IDR1_REL)) {
>>> dev_err(smmu->dev, "embedded implementation not supported\n");
>>> return -ENXIO;
>>> }
>>> /* Queue sizes, capped to ensure natural alignment */
>>> smmu->cmdq.q.llq.max_n_shift = min_t(u32, CMDQ_MAX_SZ_SHIFT,
>>> - FIELD_GET(IDR1_CMDQS, reg));
>>> + FIELD_GET(IDR1_CMDQS, smmu->idr1));
>>> if (smmu->cmdq.q.llq.max_n_shift <= ilog2(CMDQ_BATCH_ENTRIES)) {
>>> /*
>>> * We don't support splitting up batches, so one batch of
>>> @@ -3548,13 +3548,13 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>>> }
>>> smmu->evtq.q.llq.max_n_shift = min_t(u32, EVTQ_MAX_SZ_SHIFT,
>>> - FIELD_GET(IDR1_EVTQS, reg));
>>> + FIELD_GET(IDR1_EVTQS, smmu->idr1));
>>> smmu->priq.q.llq.max_n_shift = min_t(u32, PRIQ_MAX_SZ_SHIFT,
>>> - FIELD_GET(IDR1_PRIQS, reg));
>>> + FIELD_GET(IDR1_PRIQS, smmu->idr1));
>>> /* SID/SSID sizes */
>>> - smmu->ssid_bits = FIELD_GET(IDR1_SSIDSIZE, reg);
>>> - smmu->sid_bits = FIELD_GET(IDR1_SIDSIZE, reg);
>>> + smmu->ssid_bits = FIELD_GET(IDR1_SSIDSIZE, smmu->idr1);
>>> + smmu->sid_bits = FIELD_GET(IDR1_SIDSIZE, smmu->idr1);
>>> /*
>>> * If the SMMU supports fewer bits than would fill a single L2 stream
>>> @@ -3563,31 +3563,37 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>>> if (smmu->sid_bits <= STRTAB_SPLIT)
>>> smmu->features &= ~ARM_SMMU_FEAT_2_LVL_STRTAB;
>>> + /* IDR2 */
>>> + smmu->idr2 = readl_relaxed(smmu->base + ARM_SMMU_IDR2);
>>> +
>>> /* IDR3 */
>>> - reg = readl_relaxed(smmu->base + ARM_SMMU_IDR3);
>>> - if (FIELD_GET(IDR3_RIL, reg))
>>> + smmu->idr3 = readl_relaxed(smmu->base + ARM_SMMU_IDR3);
>>> + if (FIELD_GET(IDR3_RIL, smmu->idr3))
>>> smmu->features |= ARM_SMMU_FEAT_RANGE_INV;
>>> + /* IDR4 */
>>> + smmu->idr4 = readl_relaxed(smmu->base + ARM_SMMU_IDR4);
>>> +
>>> /* IDR5 */
>>> - reg = readl_relaxed(smmu->base + ARM_SMMU_IDR5);
>>> + smmu->idr5 = readl_relaxed(smmu->base + ARM_SMMU_IDR5);
>>> /* Maximum number of outstanding stalls */
>>> - smmu->evtq.max_stalls = FIELD_GET(IDR5_STALL_MAX, reg);
>>> + smmu->evtq.max_stalls = FIELD_GET(IDR5_STALL_MAX, smmu->idr5);
>>> /* Page sizes */
>>> - if (reg & IDR5_GRAN64K)
>>> + if (smmu->idr5 & IDR5_GRAN64K)
>>> smmu->pgsize_bitmap |= SZ_64K | SZ_512M;
>>> - if (reg & IDR5_GRAN16K)
>>> + if (smmu->idr5 & IDR5_GRAN16K)
>>> smmu->pgsize_bitmap |= SZ_16K | SZ_32M;
>>> - if (reg & IDR5_GRAN4K)
>>> + if (smmu->idr5 & IDR5_GRAN4K)
>>> smmu->pgsize_bitmap |= SZ_4K | SZ_2M | SZ_1G;
>>> /* Input address size */
>>> - if (FIELD_GET(IDR5_VAX, reg) == IDR5_VAX_52_BIT)
>>> + if (FIELD_GET(IDR5_VAX, smmu->idr5) == IDR5_VAX_52_BIT)
>>> smmu->features |= ARM_SMMU_FEAT_VAX;
>>> /* Output address size */
>>> - switch (FIELD_GET(IDR5_OAS, reg)) {
>>> + switch (FIELD_GET(IDR5_OAS, smmu->idr5)) {
>>> case IDR5_OAS_32_BIT:
>>> smmu->oas = 32;
>>> break;
>>> @@ -3632,6 +3638,16 @@ 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);
>>> +
>>> + /* IDR6 */
>>> + smmu->idr6 = readl_relaxed(smmu->base + ARM_SMMU_IDR6);
>>> +
>>> + /* IIDR */
>>> + smmu->iidr = readl_relaxed(smmu->base + ARM_SMMU_IIDR);
>>> +
>>> + /* AIDR */
>>> + smmu->aidr = readl_relaxed(smmu->base + ARM_SMMU_AIDR);
>>> +
>>> return 0;
>>> }
>>> @@ -3752,6 +3768,119 @@ static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
>>> return devm_ioremap_resource(dev, &res);
>>> }
>>> +static ssize_t smmu_idr0_show(struct device *dev,
>>> + struct device_attribute *attr,
>>> + char *buf)
>>> +{
>>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>>> +
>>> + return sprintf(buf, "%x\n", smmu->idr0);
>>> +}
>>> +static DEVICE_ATTR_RO(smmu_idr0);
>>> +
>>> +static ssize_t smmu_idr1_show(struct device *dev,
>>> + struct device_attribute *attr,
>>> + char *buf)
>>> +{
>>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>>> +
>>> + return sprintf(buf, "%x\n", smmu->idr1);
>>> +}
>>> +static DEVICE_ATTR_RO(smmu_idr1);
>>> +
>>> +static ssize_t smmu_idr2_show(struct device *dev,
>>> + struct device_attribute *attr,
>>> + char *buf)
>>> +{
>>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>>> +
>>> + return sprintf(buf, "%x\n", smmu->idr2);
>>> +}
>>> +static DEVICE_ATTR_RO(smmu_idr2);
>>> +
>>> +static ssize_t smmu_idr3_show(struct device *dev,
>>> + struct device_attribute *attr,
>>> + char *buf)
>>> +{
>>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>>> +
>>> + return sprintf(buf, "%x\n", smmu->idr3);
>>> +}
>>> +static DEVICE_ATTR_RO(smmu_idr3);
>>> +
>>> +static ssize_t smmu_idr4_show(struct device *dev,
>>> + struct device_attribute *attr,
>>> + char *buf)
>>> +{
>>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>>> +
>>> + return sprintf(buf, "%x\n", smmu->idr4);
>>> +}
>>> +static DEVICE_ATTR_RO(smmu_idr4);
>>> +
>>> +static ssize_t smmu_idr5_show(struct device *dev,
>>> + struct device_attribute *attr,
>>> + char *buf)
>>> +{
>>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>>> +
>>> + return sprintf(buf, "%x\n", smmu->idr5);
>>> +}
>>> +static DEVICE_ATTR_RO(smmu_idr5);
>>> +
>>> +static ssize_t smmu_idr6_show(struct device *dev,
>>> + struct device_attribute *attr,
>>> + char *buf)
>>> +{
>>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>>> +
>>> + return sprintf(buf, "%x\n", smmu->idr6);
>>> +}
>>> +static DEVICE_ATTR_RO(smmu_idr6);
>>> +
>>> +static ssize_t smmu_iidr_show(struct device *dev,
>>> + struct device_attribute *attr,
>>> + char *buf)
>>> +{
>>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>>> +
>>> + return sprintf(buf, "%x\n", smmu->iidr);
>>> +}
>>> +static DEVICE_ATTR_RO(smmu_iidr);
>>> +
>>> +static ssize_t smmu_aidr_show(struct device *dev,
>>> + struct device_attribute *attr,
>>> + char *buf)
>>> +{
>>> + struct arm_smmu_device *smmu = dev_to_arm_smmu_device(dev);
>>> +
>>> + return sprintf(buf, "%x\n", smmu->aidr);
>>> +}
>>> +static DEVICE_ATTR_RO(smmu_aidr);
>>> +
>>> +static struct attribute *arm_iommu_attrs[] = {
>>> + &dev_attr_smmu_idr0.attr,
>>> + &dev_attr_smmu_idr1.attr,
>>> + &dev_attr_smmu_idr2.attr,
>>> + &dev_attr_smmu_idr3.attr,
>>> + &dev_attr_smmu_idr4.attr,
>>> + &dev_attr_smmu_idr5.attr,
>>> + &dev_attr_smmu_idr6.attr,
>>> + &dev_attr_smmu_iidr.attr,
>>> + &dev_attr_smmu_aidr.attr,
>>> + NULL,
>>> +};
>>> +
>>> +static struct attribute_group arm_iommu_group = {
>>> + .name = "arm-iommu",
>>> + .attrs = arm_iommu_attrs,
>>> +};
>>> +
>>> +static const struct attribute_group *arm_iommu_groups[] = {
>>> + &arm_iommu_group,
>>> + NULL,
>>> +};
>>> +
>>> static int arm_smmu_device_probe(struct platform_device *pdev)
>>> {
>>> int irq, ret;
>>> @@ -3839,7 +3968,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
>>> return ret;
>>> /* And we're up. Go go go! */
>>> - ret = iommu_device_sysfs_add(&smmu->iommu, dev, NULL,
>>> + ret = iommu_device_sysfs_add(&smmu->iommu, dev, arm_iommu_groups,
>>> "smmu3.%pa", &ioaddr);
>>> if (ret)
>>> return ret;
>>> 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 cd48590ada30..ffa1123bf37c 100644
>>> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
>>> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
>>> @@ -50,9 +50,13 @@
>>> #define IDR1_SSIDSIZE GENMASK(10, 6)
>>> #define IDR1_SIDSIZE GENMASK(5, 0)
>>> +#define ARM_SMMU_IDR2 0x8
>>> +
>>> #define ARM_SMMU_IDR3 0xc
>>> #define IDR3_RIL (1 << 10)
>>> +#define ARM_SMMU_IDR4 0x10
>>> +
>>> #define ARM_SMMU_IDR5 0x14
>>> #define IDR5_STALL_MAX GENMASK(31, 16)
>>> #define IDR5_GRAN64K (1 << 6)
>>> @@ -69,6 +73,9 @@
>>> #define IDR5_VAX GENMASK(11, 10)
>>> #define IDR5_VAX_52_BIT 1
>>> +#define ARM_SMMU_IIDR 0x18
>>> +#define ARM_SMMU_AIDR 0x1C
>>> +
>>> #define ARM_SMMU_CR0 0x20
>>> #define CR0_ATSCHK (1 << 4)
>>> #define CR0_CMDQEN (1 << 3)
>>> @@ -154,6 +161,8 @@
>>> #define ARM_SMMU_REG_SZ 0xe00
>>> +#define ARM_SMMU_IDR6 0x0190
>>> +
>>> /* Common MSI config fields */
>>> #define MSI_CFG0_ADDR_MASK GENMASK_ULL(51, 2)
>>> #define MSI_CFG2_SH GENMASK(5, 4)
>>> @@ -669,6 +678,17 @@ struct arm_smmu_device {
>>> struct arm_smmu_strtab_cfg strtab_cfg;
>>> + /* SMMU feature registers */
>>> + u32 idr0;
>>> + u32 idr1;
>>> + u32 idr2;
>>> + u32 idr3;
>>> + u32 idr4;
>>> + u32 idr5;
>>> + u32 idr6;
>>> + u32 iidr;
>>> + u32 aidr;
>>> +
>>> /* IOMMU core code handle */
>>> struct iommu_device iommu;
>>> @@ -676,6 +696,13 @@ struct arm_smmu_device {
>>> struct mutex streams_mutex;
>>> };
>>> +static inline struct arm_smmu_device *dev_to_arm_smmu_device(struct device *dev)
>>> +{
>>> + struct iommu_device *iommu = dev_to_iommu_device(dev);
>>> +
>>> + return container_of(iommu, struct arm_smmu_device, iommu);
>>> +}
>>> +
>>> struct arm_smmu_stream {
>>> u32 id;
>>> struct arm_smmu_master *master;
>