[RFC PATCH v1 37/38] coco: guest: arm64: Add support for fetching device measurements

["Aneesh Kumar K.V (Arm)" <aneesh.kumar@kernel.org>]

Fetch device measurements using RSI_RDEV_GET_MEASUREMENTS.

Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
---
 arch/arm64/include/asm/rsi_cmds.h        | 11 +++++++
 arch/arm64/include/asm/rsi_smc.h         | 16 ++++++++++
 drivers/virt/coco/arm-cca-guest/rsi-da.c | 39 ++++++++++++++++++++++++
 drivers/virt/coco/arm-cca-guest/rsi-da.h |  2 ++
 4 files changed, 68 insertions(+)

diff --git a/arch/arm64/include/asm/rsi_cmds.h b/arch/arm64/include/asm/rsi_cmds.h
index 3463d571d7db..42b998f44a0e 100644
--- a/arch/arm64/include/asm/rsi_cmds.h
+++ b/arch/arm64/include/asm/rsi_cmds.h
@@ -265,4 +265,15 @@ static inline unsigned long __rsi_rdev_stop(unsigned long vdev_id, unsigned long
 	return res.a0;
 }
 
+static inline unsigned long __rsi_rdev_get_measurements(unsigned long vdev_id,
+						       unsigned long inst_id,
+						       phys_addr_t meas)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RSI_RDEV_GET_MEASUREMENTS, vdev_id, inst_id, meas, &res);
+
+	return res.a0;
+}
+
 #endif /* __ASM_RSI_CMDS_H */
diff --git a/arch/arm64/include/asm/rsi_smc.h b/arch/arm64/include/asm/rsi_smc.h
index f6aa647239c0..f051db54cdc3 100644
--- a/arch/arm64/include/asm/rsi_smc.h
+++ b/arch/arm64/include/asm/rsi_smc.h
@@ -202,6 +202,22 @@ struct rsi_host_call {
 
 #define SMC_RSI_RDEV_GET_INTERFACE_REPORT	SMC_RSI_FID(0x1a6)
 
+#define RSI_DEV_MEASURE_ALL		BIT(0)
+#define RSI_DEV_MEASURE_SIGNED		BIT(1)
+#define RSI_DEV_MEASURE_RAW		BIT(2)
+
+struct rsi_device_measurements_params {
+	union {
+		struct {
+			u64 flags;
+			u8 indices[32];
+			u8 nounce[32];
+		};
+		u8 padding[0x100];
+	};
+};
+
+#define SMC_RSI_RDEV_GET_MEASUREMENTS		SMC_RSI_FID(0x1a7)
 #define SMC_RSI_RDEV_LOCK			SMC_RSI_FID(0x1a9)
 #define SMC_RSI_RDEV_START			SMC_RSI_FID(0x1aa)
 #define SMC_RSI_RDEV_STOP			SMC_RSI_FID(0x1ab)
diff --git a/drivers/virt/coco/arm-cca-guest/rsi-da.c b/drivers/virt/coco/arm-cca-guest/rsi-da.c
index 64034d220e02..6222b10964ee 100644
--- a/drivers/virt/coco/arm-cca-guest/rsi-da.c
+++ b/drivers/virt/coco/arm-cca-guest/rsi-da.c
@@ -166,10 +166,31 @@ static long rhi_get_report(int vdev_id, int da_object_type, void **report, int *
 	return ret;
 }
 
+static inline unsigned long
+rsi_rdev_get_measurements(struct pci_dev *pdev, unsigned long vdev_id,
+			  unsigned long inst_id, phys_addr_t meas)
+{
+	unsigned long ret;
+
+	ret = __rsi_rdev_get_measurements(vdev_id, inst_id, meas);
+	if (ret != RSI_SUCCESS)
+		return ret;
+
+	do {
+		ret = rsi_rdev_continue(vdev_id, inst_id);
+	} while (ret == RSI_INCOMPLETE);
+	if (ret != RSI_SUCCESS) {
+		pci_err(pdev, "failed to communicate with the device (%lu)\n", ret);
+		return ret;
+	}
+	return RSI_SUCCESS;
+}
+
 int rsi_device_lock(struct pci_dev *pdev)
 {
 	unsigned long ret;
 	unsigned long tdisp_version;
+	struct rsi_device_measurements_params *rsi_dev_meas;
 	struct cca_guest_dsc *dsm = to_cca_guest_dsc(pdev);
 	int vdev_id = (pci_domain_nr(pdev->bus) << 16) |
 		PCI_DEVID(pdev->bus->number, pdev->devfn);
@@ -198,6 +219,17 @@ int rsi_device_lock(struct pci_dev *pdev)
 		return -EOPNOTSUPP;
 	}
 
+	rsi_dev_meas = (struct rsi_device_measurements_params *)__get_free_page(GFP_KERNEL);
+	rsi_dev_meas->flags = RSI_DEV_MEASURE_ALL;
+	ret = rsi_rdev_get_measurements(pdev, vdev_id, dsm->instance_id,
+					virt_to_phys(rsi_dev_meas));
+
+	free_page((unsigned long)rsi_dev_meas);
+	if (ret != RSI_SUCCESS) {
+		pci_err(pdev, "failed to get device measurement (%lu)\n", ret);
+		return -EIO;
+	}
+
 	/* Now make a host call to copy the interface report to guest. */
 	ret = rhi_get_report(vdev_id, RHI_DA_OBJECT_INTERFACE_REPORT,
 			     &dsm->interface_report, &dsm->interface_report_size);
@@ -213,6 +245,13 @@ int rsi_device_lock(struct pci_dev *pdev)
 		return -EIO;
 	}
 
+	ret = rhi_get_report(vdev_id, RHI_DA_OBJECT_MEASUREMENT,
+			     &dsm->measurements, &dsm->measurements_size);
+	if (ret) {
+		pci_err(pdev, "failed to get device certificate from the host (%lu)\n", ret);
+		return -EIO;
+	}
+
 	return ret;
 }
 static inline unsigned long rsi_rdev_start(struct pci_dev *pdev,
diff --git a/drivers/virt/coco/arm-cca-guest/rsi-da.h b/drivers/virt/coco/arm-cca-guest/rsi-da.h
index 71ee1edb832e..f26156d9be81 100644
--- a/drivers/virt/coco/arm-cca-guest/rsi-da.h
+++ b/drivers/virt/coco/arm-cca-guest/rsi-da.h
@@ -40,6 +40,8 @@ struct cca_guest_dsc {
 	int interface_report_size;
 	void *certificate;
 	int certificate_size;
+	void *measurements;
+	int measurements_size;
 };
 
 static inline struct cca_guest_dsc *to_cca_guest_dsc(struct pci_dev *pdev)
-- 
2.43.0