On 3/29/24 22:06, Georgi Djakov wrote:
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 <quic_c_gdjako@xxxxxxxxxxx>
---
drivers/iommu/Kconfig | 9 +
drivers/iommu/arm/arm-smmu/Makefile | 1 +
.../iommu/arm/arm-smmu/arm-smmu-qcom-tbu.c | 372 ++++++++++++++++++
drivers/iommu/arm/arm-smmu/arm-smmu-qcom.h | 2 +
drivers/iommu/arm/arm-smmu/arm-smmu.h | 2 +
5 files changed, 386 insertions(+)
create mode 100644 drivers/iommu/arm/arm-smmu/arm-smmu-qcom-tbu.c
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index 0af39bbbe3a3..b699e88f42c5 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -374,6 +374,15 @@ config ARM_SMMU_QCOM
When running on a Qualcomm platform that has the custom variant
of the ARM SMMU, this needs to be built into the SMMU driver.
+config ARM_SMMU_QCOM_TBU
+ bool "Qualcomm TBU driver"
+ depends on ARM_SMMU_QCOM
+ help
+ The SMMUs on Qualcomm platforms may include Translation Buffer
+ Units (TBUs) for each master. Enabling support for these units
+ allows to operate the TBUs and obtain additional information
+ when debugging memory management issues like context faults.
+
config ARM_SMMU_QCOM_DEBUG
bool "ARM SMMU QCOM implementation defined debug support"
depends on ARM_SMMU_QCOM
diff --git a/drivers/iommu/arm/arm-smmu/Makefile b/drivers/iommu/arm/arm-smmu/Makefile
index 2a5a95e8e3f9..c35ff78fcfd5 100644
--- a/drivers/iommu/arm/arm-smmu/Makefile
+++ b/drivers/iommu/arm/arm-smmu/Makefile
@@ -3,4 +3,5 @@ obj-$(CONFIG_QCOM_IOMMU) += qcom_iommu.o
obj-$(CONFIG_ARM_SMMU) += arm_smmu.o
arm_smmu-objs += arm-smmu.o arm-smmu-impl.o arm-smmu-nvidia.o
arm_smmu-$(CONFIG_ARM_SMMU_QCOM) += arm-smmu-qcom.o
+arm_smmu-$(CONFIG_ARM_SMMU_QCOM_TBU) += arm-smmu-qcom-tbu.o
arm_smmu-$(CONFIG_ARM_SMMU_QCOM_DEBUG) += arm-smmu-qcom-debug.o
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-tbu.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-tbu.c
new file mode 100644
index 000000000000..e3202ed89566
--- /dev/null
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-tbu.c
@@ -0,0 +1,372 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/interconnect.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/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);
+}
+
+static struct qcom_tbu *qcom_find_tbu(struct qcom_smmu *qsmmu, u32 sid)
+{
+ struct qcom_tbu *tbu;
+ u32 start, end;
+
+ mutex_lock(&tbu_list_lock);
#include <linux/cleanup.h>
guard(mutex)(&tbu_list_lock);
and remove the unlocks
similarly for the spinlocks below
Konrad
