The TCUs (Translation Control Units) and TBUs (Translation Buffer
Units) are key components of the MMU-500. Multiple TBUs are connected
to a single TCU over an interconnect. Each TBU contains a TLB that
caches page tables. The MMU-500 implements a TBU for each connected
master, and the TBU is designed, so that it is local to the master.
A common TBU DT schema is added to describe the TBUs.
The Qualcomm SDM845 and SC7280 platforms have an implementation of the
SMMU-500, that has multiple TBUs. A vendor-specific DT schema is added
to describe the resources for each TBU (register space, power-domains,
interconnects and clocks).
The TBU driver will manage the resources and allow the system to
operate the TBUs during a context fault to obtain details by doing
s1 inv, software + hardware page table walks etc. This is implemented
with ATOS/eCATs as the ATS feature is not supported. Being able to
query the TBUs is useful for debugging various hardware/software
issues on these platforms.
v8:
- Use ARM_SMMU_QCOM_DEBUG instead of a separate config option (Will)
- Replace mutex/spinlock handling with cleanup.h guard() (Konrad)
- Add missing power-domains in sdm845.dtsi (Konrad)
- Fix swapped labels in sc7280.dtsi (Konrad)
v7: https://lore.kernel.org/r/[email protected]
- Pick Reviewed-by for the DT binding (Rob)
- Don't spam the log if the dts changes are not there (Konrad)
v6: https://lore.kernel.org/r/[email protected]/
- Use SoC-specific compatibles (Krzysztof)
- Use additionalProperties: false (Krzysztof)
- Wrap description text to 80 cols (Krzysztof)
v5: https://lore.kernel.org/r/[email protected]
- Drop the common TBU bindings and child nodes. These TBU functionalities
are only Qualcomm specific and not generic. In the unmodified ARM MMU-500
implementation there are no TBU-specific resources, so just make them
standalone DT nodes. (Robin)
- The "qcom,stream-id-range" DT property now takes a phandle to the smmu
and a stream ID range.
v4: https://lore.kernel.org/r/[email protected]/
- Create a common TBU schema. Move the vendor-specific properties into
a separate schema that references the common one. (Rob)
- Drop unused DT labels in example, fix regex. (Rob)
- Properly rebase on latest code.
v3: https://lore.kernel.org/r/[email protected]
- Having a TBU is not Qualcomm specific, so allow having TBU child
nodes with no specific constraints on properties. For some of the
vendor compatibles however, add a schema to describe specific
properties and allow validation. (Rob)
- Drop the useless reg-names DT property on TBUs. (Rob)
- Make the stream-id-range DT property a common one. (Rob)
- Fix the DT example. (Rob)
- Minor fixes on the TBU driver.
- Add support for SC7280 platforms.
v2: https://lore.kernel.org/r/[email protected]
- Improve DT binding description, add full example. (Konrad)
- Drop Qcom specific stuff from the generic binding. (Rob)
- Unconditionally try to populate subnodes. (Konrad)
- Improve TBU driver commit text, remove memory barriers. (Bjorn)
- Move TBU stuff into separate file. Make the driver builtin.
- TODO: Evaluate whether to keep TBU support as a separate driver
or just instantiate things from qcom_smmu_impl_init()
v1: https://lore.kernel.org/r/[email protected]
Georgi Djakov (7):
dt-bindings: iommu: Add Qualcomm TBU
iommu/arm-smmu-qcom-debug: Add support for TBUs
iommu/arm-smmu: Allow using a threaded handler for context interrupts
iommu/arm-smmu-qcom: Use a custom context fault handler for sdm845
arm64: dts: qcom: sdm845: Add DT nodes for the TBUs
iommu/arm-smmu-qcom: Use the custom fault handler on more platforms
arm64: dts: qcom: sc7280: Add DT nodes for the TBUs
.../devicetree/bindings/iommu/qcom,tbu.yaml | 69 +++
arch/arm64/boot/dts/qcom/sc7280.dtsi | 89 ++++
arch/arm64/boot/dts/qcom/sdm845.dtsi | 73 +++
drivers/iommu/Kconfig | 12 +-
.../iommu/arm/arm-smmu/arm-smmu-qcom-debug.c | 496 ++++++++++++++++++
drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 8 +
drivers/iommu/arm/arm-smmu/arm-smmu-qcom.h | 2 +
drivers/iommu/arm/arm-smmu/arm-smmu.c | 12 +-
drivers/iommu/arm/arm-smmu/arm-smmu.h | 3 +
9 files changed, 758 insertions(+), 6 deletions(-)
create mode 100644 Documentation/devicetree/bindings/iommu/qcom,tbu.yaml
Threaded IRQ handlers run in a less critical context compared to normal
IRQs, so they can perform more complex and time-consuming operations
without causing significant delays in other parts of the kernel.
During a context fault, it might be needed to do more processing and
gather debug information from TBUs in the handler. These operations may
sleep, so add an option to use a threaded IRQ handler in these cases.
Signed-off-by: Georgi Djakov <[email protected]>
---
drivers/iommu/arm/arm-smmu/arm-smmu.c | 12 ++++++++++--
drivers/iommu/arm/arm-smmu/arm-smmu.h | 1 +
2 files changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index c572d877b0e1..dcf0479363c3 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -806,8 +806,16 @@ static int arm_smmu_init_domain_context(struct arm_smmu_domain *smmu_domain,
else
context_fault = arm_smmu_context_fault;
- ret = devm_request_irq(smmu->dev, irq, context_fault, IRQF_SHARED,
- "arm-smmu-context-fault", smmu_domain);
+ if (smmu->impl && smmu->impl->context_fault_needs_threaded_irq)
+ ret = devm_request_threaded_irq(smmu->dev, irq, NULL,
+ context_fault,
+ IRQF_ONESHOT | IRQF_SHARED,
+ "arm-smmu-context-fault",
+ smmu_domain);
+ else
+ ret = devm_request_irq(smmu->dev, irq, context_fault, IRQF_SHARED,
+ "arm-smmu-context-fault", smmu_domain);
+
if (ret < 0) {
dev_err(smmu->dev, "failed to request context IRQ %d (%u)\n",
cfg->irptndx, irq);
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.h b/drivers/iommu/arm/arm-smmu/arm-smmu.h
index 1670e95c4637..4765c6945c34 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.h
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.h
@@ -438,6 +438,7 @@ struct arm_smmu_impl {
int (*def_domain_type)(struct device *dev);
irqreturn_t (*global_fault)(int irq, void *dev);
irqreturn_t (*context_fault)(int irq, void *dev);
+ bool context_fault_needs_threaded_irq;
int (*alloc_context_bank)(struct arm_smmu_domain *smmu_domain,
struct arm_smmu_device *smmu,
struct device *dev, int start);
The "apps_smmu" on the Qualcomm sdm845 platform is an implementation
of the SMMU-500, that consists of a single TCU (Translation Control
Unit) and multiple TBUs (Translation Buffer Units). These TBUs have
hardware debugging features that are specific and only present on
Qualcomm hardware. Represent them as independent DT nodes. List all
the resources that are needed to operate them (such as registers,
clocks, power domains and interconnects).
Reviewed-by: Rob Herring <[email protected]>
Signed-off-by: Georgi Djakov <[email protected]>
---
.../devicetree/bindings/iommu/qcom,tbu.yaml | 69 +++++++++++++++++++
1 file changed, 69 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iommu/qcom,tbu.yaml
diff --git a/Documentation/devicetree/bindings/iommu/qcom,tbu.yaml b/Documentation/devicetree/bindings/iommu/qcom,tbu.yaml
new file mode 100644
index 000000000000..82dfe935573e
--- /dev/null
+++ b/Documentation/devicetree/bindings/iommu/qcom,tbu.yaml
@@ -0,0 +1,69 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iommu/qcom,tbu.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm TBU (Translation Buffer Unit)
+
+maintainers:
+ - Georgi Djakov <[email protected]>
+
+description:
+ The Qualcomm SMMU500 implementation consists of TCU and TBU. The TBU contains
+ a Translation Lookaside Buffer (TLB) that caches page tables. TBUs provides
+ debug features to trace and trigger debug transactions. There are multiple TBU
+ instances with each client core.
+
+properties:
+ compatible:
+ enum:
+ - qcom,sc7280-tbu
+ - qcom,sdm845-tbu
+
+ reg:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+
+ interconnects:
+ maxItems: 1
+
+ power-domains:
+ maxItems: 1
+
+ qcom,stream-id-range:
+ description: |
+ Phandle of a SMMU device and Stream ID range (address and size) that
+ is assigned by the TBU
+ $ref: /schemas/types.yaml#/definitions/phandle-array
+ items:
+ - items:
+ - description: phandle of a smmu node
+ - description: stream id base address
+ - description: stream id size
+
+required:
+ - compatible
+ - reg
+ - qcom,stream-id-range
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/clock/qcom,gcc-sdm845.h>
+ #include <dt-bindings/interconnect/qcom,icc.h>
+ #include <dt-bindings/interconnect/qcom,sdm845.h>
+
+ tbu@150e1000 {
+ compatible = "qcom,sdm845-tbu";
+ reg = <0x150e1000 0x1000>;
+ clocks = <&gcc GCC_AGGRE_NOC_PCIE_TBU_CLK>;
+ interconnects = <&system_noc MASTER_GNOC_SNOC QCOM_ICC_TAG_ACTIVE_ONLY
+ &config_noc SLAVE_IMEM_CFG QCOM_ICC_TAG_ACTIVE_ONLY>;
+ power-domains = <&gcc HLOS1_VOTE_AGGRE_NOC_MMU_PCIE_TBU_GDSC>;
+ qcom,stream-id-range = <&apps_smmu 0x1c00 0x400>;
+ };
+...
Operating the TBUs (Translation Buffer Units) from Linux on Qualcomm
platforms can help with debugging context faults. To help with that,
the TBUs can run ATOS (Address Translation Operations) to manually
trigger address translation of IOVA to physical address in hardware
and provide more details when a context fault happens.
The driver will control the resources needed by the TBU to allow
running the debug operations such as ATOS, check for outstanding
transactions, do snapshot capture etc.
Signed-off-by: Georgi Djakov <[email protected]>
---
drivers/iommu/Kconfig | 12 +-
.../iommu/arm/arm-smmu/arm-smmu-qcom-debug.c | 353 ++++++++++++++++++
drivers/iommu/arm/arm-smmu/arm-smmu-qcom.h | 2 +
drivers/iommu/arm/arm-smmu/arm-smmu.h | 2 +
4 files changed, 365 insertions(+), 4 deletions(-)
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index 0af39bbbe3a3..0ac80e1094f3 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -379,10 +379,14 @@ config ARM_SMMU_QCOM_DEBUG
depends on ARM_SMMU_QCOM
help
Support for implementation specific debug features in ARM SMMU
- hardware found in QTI platforms.
-
- Say Y here to enable debug for issues such as TLB sync timeouts
- which requires implementation defined register dumps.
+ hardware found in QTI platforms. This include support for
+ the Translation Buffer Units (TBU) that can be used to obtain
+ additional information when debugging memory management issues
+ like context faults.
+
+ Say Y here to enable debug for issues such as context faults
+ or TLB sync timeouts which requires implementation defined
+ register dumps.
config ARM_SMMU_V3
tristate "ARM Ltd. System MMU Version 3 (SMMUv3) Support"
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c
index bb89d49adf8d..eff7ca94ec8d 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c
@@ -1,15 +1,66 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
*/
+#include <linux/cleanup.h>
#include <linux/device.h>
+#include <linux/interconnect.h>
#include <linux/firmware/qcom/qcom_scm.h>
+#include <linux/iopoll.h>
+#include <linux/list.h>
+#include <linux/mod_devicetable.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
#include <linux/ratelimit.h>
+#include <linux/spinlock.h>
#include "arm-smmu.h"
#include "arm-smmu-qcom.h"
+#define TBU_DBG_TIMEOUT_US 100
+#define DEBUG_AXUSER_REG 0x30
+#define DEBUG_AXUSER_CDMID GENMASK_ULL(43, 36)
+#define DEBUG_AXUSER_CDMID_VAL 0xff
+#define DEBUG_PAR_REG 0x28
+#define DEBUG_PAR_FAULT_VAL BIT(0)
+#define DEBUG_PAR_PA GENMASK_ULL(47, 12)
+#define DEBUG_SID_HALT_REG 0x0
+#define DEBUG_SID_HALT_VAL BIT(16)
+#define DEBUG_SID_HALT_SID GENMASK(9, 0)
+#define DEBUG_SR_HALT_ACK_REG 0x20
+#define DEBUG_SR_HALT_ACK_VAL BIT(1)
+#define DEBUG_SR_ECATS_RUNNING_VAL BIT(0)
+#define DEBUG_TXN_AXCACHE GENMASK(5, 2)
+#define DEBUG_TXN_AXPROT GENMASK(8, 6)
+#define DEBUG_TXN_AXPROT_PRIV 0x1
+#define DEBUG_TXN_AXPROT_NSEC 0x2
+#define DEBUG_TXN_TRIGG_REG 0x18
+#define DEBUG_TXN_TRIGGER BIT(0)
+#define DEBUG_VA_ADDR_REG 0x8
+
+static LIST_HEAD(tbu_list);
+static DEFINE_MUTEX(tbu_list_lock);
+static DEFINE_SPINLOCK(atos_lock);
+
+struct qcom_tbu {
+ struct device *dev;
+ struct device_node *smmu_np;
+ u32 sid_range[2];
+ struct list_head list;
+ struct clk *clk;
+ struct icc_path *path;
+ void __iomem *base;
+ spinlock_t halt_lock; /* multiple halt or resume can't execute concurrently */
+ int halt_count;
+};
+
+static struct qcom_smmu *to_qcom_smmu(struct arm_smmu_device *smmu)
+{
+ return container_of(smmu, struct qcom_smmu, smmu);
+}
+
void qcom_smmu_tlb_sync_debug(struct arm_smmu_device *smmu)
{
int ret;
@@ -49,3 +100,305 @@ void qcom_smmu_tlb_sync_debug(struct arm_smmu_device *smmu)
tbu_pwr_status, sync_inv_ack, sync_inv_progress);
}
}
+
+static struct qcom_tbu *qcom_find_tbu(struct qcom_smmu *qsmmu, u32 sid)
+{
+ struct qcom_tbu *tbu;
+ u32 start, end;
+
+ guard(mutex)(&tbu_list_lock);
+
+ if (list_empty(&tbu_list))
+ return NULL;
+
+ list_for_each_entry(tbu, &tbu_list, list) {
+ start = tbu->sid_range[0];
+ end = start + tbu->sid_range[1];
+
+ if (qsmmu->smmu.dev->of_node == tbu->smmu_np &&
+ start <= sid && sid < end)
+ return tbu;
+ }
+ dev_err(qsmmu->smmu.dev, "Unable to find TBU for sid 0x%x\n", sid);
+
+ return NULL;
+}
+
+static int qcom_tbu_halt(struct qcom_tbu *tbu, struct arm_smmu_domain *smmu_domain)
+{
+ struct arm_smmu_device *smmu = smmu_domain->smmu;
+ int ret = 0, idx = smmu_domain->cfg.cbndx;
+ u32 val, fsr, status;
+
+ guard(spinlock_irqsave)(&tbu->halt_lock);
+ if (tbu->halt_count) {
+ tbu->halt_count++;
+ return ret;
+ }
+
+ val = readl_relaxed(tbu->base + DEBUG_SID_HALT_REG);
+ val |= DEBUG_SID_HALT_VAL;
+ writel_relaxed(val, tbu->base + DEBUG_SID_HALT_REG);
+
+ fsr = arm_smmu_cb_read(smmu, idx, ARM_SMMU_CB_FSR);
+ if ((fsr & ARM_SMMU_FSR_FAULT) && (fsr & ARM_SMMU_FSR_SS)) {
+ u32 sctlr_orig, sctlr;
+
+ /*
+ * We are in a fault. Our request to halt the bus will not
+ * complete until transactions in front of us (such as the fault
+ * itself) have completed. Disable iommu faults and terminate
+ * any existing transactions.
+ */
+ sctlr_orig = arm_smmu_cb_read(smmu, idx, ARM_SMMU_CB_SCTLR);
+ sctlr = sctlr_orig & ~(ARM_SMMU_SCTLR_CFCFG | ARM_SMMU_SCTLR_CFIE);
+ arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_SCTLR, sctlr);
+ arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_FSR, fsr);
+ arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_RESUME, ARM_SMMU_RESUME_TERMINATE);
+ arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_SCTLR, sctlr_orig);
+ }
+
+ if (readl_poll_timeout_atomic(tbu->base + DEBUG_SR_HALT_ACK_REG, status,
+ (status & DEBUG_SR_HALT_ACK_VAL),
+ 0, TBU_DBG_TIMEOUT_US)) {
+ dev_err(tbu->dev, "Timeout while trying to halt TBU!\n");
+ ret = -ETIMEDOUT;
+
+ val = readl_relaxed(tbu->base + DEBUG_SID_HALT_REG);
+ val &= ~DEBUG_SID_HALT_VAL;
+ writel_relaxed(val, tbu->base + DEBUG_SID_HALT_REG);
+
+ return ret;
+ }
+
+ tbu->halt_count = 1;
+
+ return ret;
+}
+
+static void qcom_tbu_resume(struct qcom_tbu *tbu)
+{
+ u32 val;
+
+ guard(spinlock_irqsave)(&tbu->halt_lock);
+ if (!tbu->halt_count) {
+ WARN(1, "%s: halt_count is 0", dev_name(tbu->dev));
+ return;
+ }
+
+ if (tbu->halt_count > 1) {
+ tbu->halt_count--;
+ return;
+ }
+
+ val = readl_relaxed(tbu->base + DEBUG_SID_HALT_REG);
+ val &= ~DEBUG_SID_HALT_VAL;
+ writel_relaxed(val, tbu->base + DEBUG_SID_HALT_REG);
+
+ tbu->halt_count = 0;
+}
+
+static phys_addr_t qcom_tbu_trigger_atos(struct arm_smmu_domain *smmu_domain,
+ struct qcom_tbu *tbu, dma_addr_t iova, u32 sid)
+{
+ bool atos_timedout = false;
+ phys_addr_t phys = 0;
+ ktime_t timeout;
+ u64 val;
+
+ /* Set address and stream-id */
+ val = readq_relaxed(tbu->base + DEBUG_SID_HALT_REG);
+ val &= ~DEBUG_SID_HALT_SID;
+ val |= FIELD_PREP(DEBUG_SID_HALT_SID, sid);
+ writeq_relaxed(val, tbu->base + DEBUG_SID_HALT_REG);
+ writeq_relaxed(iova, tbu->base + DEBUG_VA_ADDR_REG);
+ val = FIELD_PREP(DEBUG_AXUSER_CDMID, DEBUG_AXUSER_CDMID_VAL);
+ writeq_relaxed(val, tbu->base + DEBUG_AXUSER_REG);
+
+ /* Write-back read and write-allocate */
+ val = FIELD_PREP(DEBUG_TXN_AXCACHE, 0xf);
+
+ /* Non-secure access */
+ val |= FIELD_PREP(DEBUG_TXN_AXPROT, DEBUG_TXN_AXPROT_NSEC);
+
+ /* Privileged access */
+ val |= FIELD_PREP(DEBUG_TXN_AXPROT, DEBUG_TXN_AXPROT_PRIV);
+
+ val |= DEBUG_TXN_TRIGGER;
+ writeq_relaxed(val, tbu->base + DEBUG_TXN_TRIGG_REG);
+
+ timeout = ktime_add_us(ktime_get(), TBU_DBG_TIMEOUT_US);
+ for (;;) {
+ val = readl_relaxed(tbu->base + DEBUG_SR_HALT_ACK_REG);
+ if (!(val & DEBUG_SR_ECATS_RUNNING_VAL))
+ break;
+ val = readl_relaxed(tbu->base + DEBUG_PAR_REG);
+ if (val & DEBUG_PAR_FAULT_VAL)
+ break;
+ if (ktime_compare(ktime_get(), timeout) > 0) {
+ atos_timedout = true;
+ break;
+ }
+ }
+
+ val = readq_relaxed(tbu->base + DEBUG_PAR_REG);
+ if (val & DEBUG_PAR_FAULT_VAL)
+ dev_err(tbu->dev, "ATOS generated a fault interrupt! PAR = %llx, SID=0x%x\n",
+ val, sid);
+ else if (atos_timedout)
+ dev_err_ratelimited(tbu->dev, "ATOS translation timed out!\n");
+ else
+ phys = FIELD_GET(DEBUG_PAR_PA, val);
+
+ /* Reset hardware */
+ writeq_relaxed(0, tbu->base + DEBUG_TXN_TRIGG_REG);
+ writeq_relaxed(0, tbu->base + DEBUG_VA_ADDR_REG);
+ val = readl_relaxed(tbu->base + DEBUG_SID_HALT_REG);
+ val &= ~DEBUG_SID_HALT_SID;
+ writel_relaxed(val, tbu->base + DEBUG_SID_HALT_REG);
+
+ return phys;
+}
+
+static phys_addr_t qcom_iova_to_phys(struct arm_smmu_domain *smmu_domain,
+ dma_addr_t iova, u32 sid)
+{
+ struct arm_smmu_device *smmu = smmu_domain->smmu;
+ struct qcom_smmu *qsmmu = to_qcom_smmu(smmu);
+ int idx = smmu_domain->cfg.cbndx;
+ struct qcom_tbu *tbu;
+ u32 sctlr_orig, sctlr;
+ phys_addr_t phys = 0;
+ int attempt = 0;
+ int ret;
+ u64 fsr;
+
+ tbu = qcom_find_tbu(qsmmu, sid);
+ if (!tbu)
+ return 0;
+
+ ret = icc_set_bw(tbu->path, 0, UINT_MAX);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(tbu->clk);
+ if (ret)
+ goto disable_icc;
+
+ ret = qcom_tbu_halt(tbu, smmu_domain);
+ if (ret)
+ goto disable_clk;
+
+ /*
+ * ATOS/ECATS can trigger the fault interrupt, so disable it temporarily
+ * and check for an interrupt manually.
+ */
+ sctlr_orig = arm_smmu_cb_read(smmu, idx, ARM_SMMU_CB_SCTLR);
+ sctlr = sctlr_orig & ~(ARM_SMMU_SCTLR_CFCFG | ARM_SMMU_SCTLR_CFIE);
+ arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_SCTLR, sctlr);
+
+ fsr = arm_smmu_cb_read(smmu, idx, ARM_SMMU_CB_FSR);
+ if (fsr & ARM_SMMU_FSR_FAULT) {
+ /* Clear pending interrupts */
+ arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_FSR, fsr);
+
+ /*
+ * TBU halt takes care of resuming any stalled transcation.
+ * Kept it here for completeness sake.
+ */
+ if (fsr & ARM_SMMU_FSR_SS)
+ arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_RESUME,
+ ARM_SMMU_RESUME_TERMINATE);
+ }
+
+ /* Only one concurrent atos operation */
+ scoped_guard(spinlock_irqsave, &atos_lock) {
+ /*
+ * If the translation fails, attempt the lookup more time."
+ */
+ do {
+ phys = qcom_tbu_trigger_atos(smmu_domain, tbu, iova, sid);
+
+ fsr = arm_smmu_cb_read(smmu, idx, ARM_SMMU_CB_FSR);
+ if (fsr & ARM_SMMU_FSR_FAULT) {
+ /* Clear pending interrupts */
+ arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_FSR, fsr);
+
+ if (fsr & ARM_SMMU_FSR_SS)
+ arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_RESUME,
+ ARM_SMMU_RESUME_TERMINATE);
+ }
+ } while (!phys && attempt++ < 2);
+
+ arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_SCTLR, sctlr_orig);
+ }
+ qcom_tbu_resume(tbu);
+
+ /* Read to complete prior write transcations */
+ readl_relaxed(tbu->base + DEBUG_SR_HALT_ACK_REG);
+
+disable_clk:
+ clk_disable_unprepare(tbu->clk);
+disable_icc:
+ icc_set_bw(tbu->path, 0, 0);
+
+ return phys;
+}
+
+static int qcom_tbu_probe(struct platform_device *pdev)
+{
+ struct of_phandle_args args = { .args_count = 2 };
+ struct device_node *np = pdev->dev.of_node;
+ struct device *dev = &pdev->dev;
+ struct qcom_tbu *tbu;
+
+ tbu = devm_kzalloc(dev, sizeof(*tbu), GFP_KERNEL);
+ if (!tbu)
+ return -ENOMEM;
+
+ tbu->dev = dev;
+ INIT_LIST_HEAD(&tbu->list);
+ spin_lock_init(&tbu->halt_lock);
+
+ if (of_parse_phandle_with_args(np, "qcom,stream-id-range", "#iommu-cells", 0, &args)) {
+ dev_err(dev, "Cannot parse the 'qcom,stream-id-range' DT property\n");
+ return -EINVAL;
+ }
+
+ tbu->smmu_np = args.np;
+ tbu->sid_range[0] = args.args[0];
+ tbu->sid_range[1] = args.args[1];
+ of_node_put(args.np);
+
+ tbu->base = devm_of_iomap(dev, np, 0, NULL);
+ if (IS_ERR(tbu->base))
+ return PTR_ERR(tbu->base);
+
+ tbu->clk = devm_clk_get_optional(dev, NULL);
+ if (IS_ERR(tbu->clk))
+ return PTR_ERR(tbu->clk);
+
+ tbu->path = devm_of_icc_get(dev, NULL);
+ if (IS_ERR(tbu->path))
+ return PTR_ERR(tbu->path);
+
+ guard(mutex)(&tbu_list_lock);
+ list_add_tail(&tbu->list, &tbu_list);
+
+ return 0;
+}
+
+static const struct of_device_id qcom_tbu_of_match[] = {
+ { .compatible = "qcom,sc7280-tbu" },
+ { .compatible = "qcom,sdm845-tbu" },
+ { }
+};
+
+static struct platform_driver qcom_tbu_driver = {
+ .driver = {
+ .name = "qcom_tbu",
+ .of_match_table = qcom_tbu_of_match,
+ },
+ .probe = qcom_tbu_probe,
+};
+builtin_platform_driver(qcom_tbu_driver);
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.h b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.h
index 593910567b88..9bb3ae7d62da 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.h
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.h
@@ -30,6 +30,8 @@ struct qcom_smmu_match_data {
const struct arm_smmu_impl *adreno_impl;
};
+irqreturn_t qcom_smmu_context_fault(int irq, void *dev);
+
#ifdef CONFIG_ARM_SMMU_QCOM_DEBUG
void qcom_smmu_tlb_sync_debug(struct arm_smmu_device *smmu);
#else
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.h b/drivers/iommu/arm/arm-smmu/arm-smmu.h
index 836ed6799a80..1670e95c4637 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.h
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.h
@@ -136,6 +136,7 @@ enum arm_smmu_cbar_type {
#define ARM_SMMU_CBAR_VMID GENMASK(7, 0)
#define ARM_SMMU_GR1_CBFRSYNRA(n) (0x400 + ((n) << 2))
+#define ARM_SMMU_CBFRSYNRA_SID GENMASK(15, 0)
#define ARM_SMMU_GR1_CBA2R(n) (0x800 + ((n) << 2))
#define ARM_SMMU_CBA2R_VMID16 GENMASK(31, 16)
@@ -238,6 +239,7 @@ enum arm_smmu_cbar_type {
#define ARM_SMMU_CB_ATSR 0x8f0
#define ARM_SMMU_ATSR_ACTIVE BIT(0)
+#define ARM_SMMU_RESUME_TERMINATE BIT(0)
/* Maximum number of context banks per SMMU */
#define ARM_SMMU_MAX_CBS 128
On Wed, 17 Apr 2024 06:37:24 -0700, Georgi Djakov wrote:
> The TCUs (Translation Control Units) and TBUs (Translation Buffer
> Units) are key components of the MMU-500. Multiple TBUs are connected
> to a single TCU over an interconnect. Each TBU contains a TLB that
> caches page tables. The MMU-500 implements a TBU for each connected
> master, and the TBU is designed, so that it is local to the master.
> A common TBU DT schema is added to describe the TBUs.
>
> [...]
Applied driver and binding updates to will (for-joerg/arm-smmu/updates),
thanks!
[1/7] dt-bindings: iommu: Add Qualcomm TBU
https://git.kernel.org/will/c/54a75d8f14c5
[2/7] iommu/arm-smmu-qcom-debug: Add support for TBUs
https://git.kernel.org/will/c/414ecb030870
[3/7] iommu/arm-smmu: Allow using a threaded handler for context interrupts
https://git.kernel.org/will/c/960be6e10d4f
[4/7] iommu/arm-smmu-qcom: Use a custom context fault handler for sdm845
https://git.kernel.org/will/c/d374555ef993
[6/7] iommu/arm-smmu-qcom: Use the custom fault handler on more platforms
https://git.kernel.org/will/c/b8ca7ce709f8
Cheers,
--
Will
https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev
Hi Georgi,
On Wed, Apr 17, 2024 at 06:37:26AM -0700, Georgi Djakov wrote:
> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c
> index bb89d49adf8d..eff7ca94ec8d 100644
> --- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c
> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c
..
> +static const struct of_device_id qcom_tbu_of_match[] = {
> + { .compatible = "qcom,sc7280-tbu" },
> + { .compatible = "qcom,sdm845-tbu" },
> + { }
> +};
> +
> +static struct platform_driver qcom_tbu_driver = {
> + .driver = {
> + .name = "qcom_tbu",
> + .of_match_table = qcom_tbu_of_match,
> + },
> + .probe = qcom_tbu_probe,
> +};
> +builtin_platform_driver(qcom_tbu_driver);
I just noticed that this breaks a modular build of the arm-smmu driver
because we now have two init functions for the module:
ld.lld: error: duplicate symbol: init_module
>>> defined at arm-smmu.c
>>> drivers/iommu/arm/arm-smmu/arm-smmu.o:(init_module)
>>> defined at arm-smmu-qcom-debug.c
>>> drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.o:(.init.text+0x4)
I think you should initialise the TBU debug feature by calling into it
manually from qcom_smmu_impl_init().
Please can you send a patch to fix that? For now, I'll bodge it so that
the qcom debug stuff doesn't build as a module (see below).
Cheers,
Will
--->8
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index 032bfd681307..66325210c8c9 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -376,7 +376,7 @@ config ARM_SMMU_QCOM
config ARM_SMMU_QCOM_DEBUG
bool "ARM SMMU QCOM implementation defined debug support"
- depends on ARM_SMMU_QCOM
+ depends on ARM_SMMU_QCOM=y
help
Support for implementation specific debug features in ARM SMMU
hardware found in QTI platforms. This include support for
Hi Will,
On 1.05.24 17:34, Will Deacon wrote:
> Hi Georgi,
>
> On Wed, Apr 17, 2024 at 06:37:26AM -0700, Georgi Djakov wrote:
>> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c
>> index bb89d49adf8d..eff7ca94ec8d 100644
>> --- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c
>> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c
>
> ...
>
>> +static const struct of_device_id qcom_tbu_of_match[] = {
>> + { .compatible = "qcom,sc7280-tbu" },
>> + { .compatible = "qcom,sdm845-tbu" },
>> + { }
>> +};
>> +
>> +static struct platform_driver qcom_tbu_driver = {
>> + .driver = {
>> + .name = "qcom_tbu",
>> + .of_match_table = qcom_tbu_of_match,
>> + },
>> + .probe = qcom_tbu_probe,
>> +};
>> +builtin_platform_driver(qcom_tbu_driver);
>
> I just noticed that this breaks a modular build of the arm-smmu driver
> because we now have two init functions for the module:
>
> ld.lld: error: duplicate symbol: init_module
> >>> defined at arm-smmu.c
> >>> drivers/iommu/arm/arm-smmu/arm-smmu.o:(init_module)
> >>> defined at arm-smmu-qcom-debug.c
> >>> drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.o:(.init.text+0x4)
>
> I think you should initialise the TBU debug feature by calling into it
> manually from qcom_smmu_impl_init().
>
> Please can you send a patch to fix that? For now, I'll bodge it so that
> the qcom debug stuff doesn't build as a module (see below).
Š¢hanks for sorting that out and apologies for missing it. We are at rc6 now and
i am afraid that i won't be able to validate my patch until next week (Easter
holidays here). I'll definitely send the rework when I get back.
BR,
Georgi
>
> Cheers,
>
> Will
>
> --->8
>
> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
> index 032bfd681307..66325210c8c9 100644
> --- a/drivers/iommu/Kconfig
> +++ b/drivers/iommu/Kconfig
> @@ -376,7 +376,7 @@ config ARM_SMMU_QCOM
>
> config ARM_SMMU_QCOM_DEBUG
> bool "ARM SMMU QCOM implementation defined debug support"
> - depends on ARM_SMMU_QCOM
> + depends on ARM_SMMU_QCOM=y
> help
> Support for implementation specific debug features in ARM SMMU
> hardware found in QTI platforms. This include support for
>