[RFC PATCH v4 09/14] coco: host: arm64: Initialize RMM pdev state for TDISP IDE connect

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

Update connect() to:
- allocate device-communication buffers,
- create the RMM pdev object,
- perform initial device communication to collect identity, and
- set the device public key when the pdev enters NEEDS_KEY.

Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
---
 drivers/virt/coco/arm-cca-host/arm-cca.c | 43 +++++++++--
 drivers/virt/coco/arm-cca-host/rmi-da.c  | 92 +++++++++++++++++++++++-
 drivers/virt/coco/arm-cca-host/rmi-da.h  |  3 +
 3 files changed, 128 insertions(+), 10 deletions(-)

diff --git a/drivers/virt/coco/arm-cca-host/arm-cca.c b/drivers/virt/coco/arm-cca-host/arm-cca.c
index 3c854aab95cc..f0aa4e46e96c 100644
--- a/drivers/virt/coco/arm-cca-host/arm-cca.c
+++ b/drivers/virt/coco/arm-cca-host/arm-cca.c
@@ -66,7 +66,7 @@ static void cca_tsm_pci_remove(struct pci_tsm *tsm)
 	}
 }
 
-static __maybe_unused int init_dev_communication_buffers(struct pci_dev *pdev,
+static int init_dev_communication_buffers(struct pci_dev *pdev,
 		struct cca_host_comm_data *comm_data)
 {
 	int ret = -ENOMEM;
@@ -184,15 +184,40 @@ static int cca_tsm_connect(struct pci_dev *pdev)
 		ret = tsm_ide_stream_register(ide);
 		if (ret)
 			goto err_tsm;
+	}
 
-		/*
-		 * Once ide is setup, enable the stream at the endpoint
-		 * Root port will be done by RMM
-		 */
-		pci_ide_stream_enable(pdev, ide);
+	ret = init_dev_communication_buffers(pdev, &pf0_ep_dsc->pdev.comm_data);
+	if (ret)
+		goto err_comm_buff;
+	ret = cca_pdev_create(pdev);
+	if (ret)
+		goto err_pdev_create;
+
+	ret = cca_pdev_collect_identity(pdev);
+	if (ret)
+		goto pdev_destroy;
+
+	if (cca_pdev_needs_key(pdev)) {
+		ret = cca_pdev_set_public_key(pdev);
+		if (ret)
+			goto pdev_destroy;
 	}
+	/*
+	 * Once ide is setup, enable the stream at the endpoint
+	 * Root port will be done by RMM
+	 */
+	if (cca_pdev_need_sel_ide_streams(pdev))
+		pci_ide_stream_enable(pdev, ide);
+
 	return 0;
 
+pdev_destroy:
+	cca_pdev_stop_and_destroy(pdev);
+err_pdev_create:
+	free_dev_communication_buffers(&pf0_ep_dsc->pdev.comm_data);
+err_comm_buff:
+	if (cca_pdev_need_sel_ide_streams(pdev))
+		tsm_ide_stream_unregister(ide);
 err_tsm:
 	if (cca_pdev_need_sel_ide_streams(pdev)) {
 		pci_ide_stream_teardown(rp, ide);
@@ -222,12 +247,16 @@ static void cca_tsm_disconnect(struct pci_dev *pdev)
 	if (cca_pdev_need_sel_ide_streams(pdev)) {
 		ide = pf0_ep_dsc->sel_stream;
 		stream_id = ide->stream_id;
+	}
+
+	cca_pdev_stop_and_destroy(pdev);
+	free_dev_communication_buffers(&pf0_ep_dsc->pdev.comm_data);
 
+	if (cca_pdev_need_sel_ide_streams(pdev)) {
 		pci_ide_stream_release(ide);
 		pf0_ep_dsc->sel_stream = NULL;
 		clear_bit(stream_id, cca_stream_ids);
 	}
-
 }
 
 static struct pci_tsm_ops cca_link_pci_ops = {
diff --git a/drivers/virt/coco/arm-cca-host/rmi-da.c b/drivers/virt/coco/arm-cca-host/rmi-da.c
index 996979dba709..cb654d1b2eb3 100644
--- a/drivers/virt/coco/arm-cca-host/rmi-da.c
+++ b/drivers/virt/coco/arm-cca-host/rmi-da.c
@@ -386,7 +386,7 @@ static int wait_for_pdev_state(struct pci_tsm *tsm, enum rmi_pdev_state target_s
 	return wait_for_dev_state(PDEV_COMMUNICATE, tsm, target_state, RMI_PDEV_ERROR);
 }
 
-static int __maybe_unused parse_certificate_chain(struct pci_tsm *tsm)
+static int parse_certificate_chain(struct pci_tsm *tsm)
 {
 	struct cca_host_pf0_ep_dsc *pf0_ep_dsc;
 	unsigned int chain_size;
@@ -484,7 +484,7 @@ static inline int copy_key_part(u8 *buf, const u8 *key_buf, size_t sz)
 }
 
 DEFINE_FREE(key_param_free, struct rmi_public_key_params *, if (_T) key_param_free(_T))
-static int __maybe_unused pdev_set_public_key(struct pci_tsm *tsm)
+static int pdev_set_public_key(struct pci_tsm *tsm)
 {
 	struct cca_host_pf0_ep_dsc *pf0_ep_dsc;
 
@@ -581,8 +581,94 @@ static int submit_pdev_state_transition_work(struct pci_dev *pdev,
 	return 0;
 }
 
+static void pdev_collect_identity_workfn(struct work_struct *work)
+{
+	struct pci_tsm *tsm;
+	struct dev_comm_work *setup_work;
+	struct cca_host_pdev_dsc *pdev_dsc;
+
+	setup_work = container_of(work, struct dev_comm_work, work);
+	tsm = setup_work->tsm;
+	pdev_dsc = to_cca_pdev_dsc(tsm->dsm_dev);
+
+	guard(mutex)(&pdev_dsc->object_lock);
+
+	do_dev_communicate(PDEV_COMMUNICATE, tsm, RMI_PDEV_ERROR);
+
+	/*
+	 * Don't worry about communication error. The caller will look at
+	 * device state to find more about error
+	 */
+}
+
+int cca_pdev_collect_identity(struct pci_dev *pdev)
+{
+	enum rmi_pdev_state state;
+	struct dev_comm_work comm_work;
+	struct cca_host_pdev_dsc *pdev_dsc = to_cca_pdev_dsc(pdev);
+	struct cca_host_comm_data *comm_data = to_cca_comm_data(pdev);
+
+	/*
+	 * Device identity is collected by doing a device communication
+	 * after a pdev_create
+	 */
+	INIT_WORK_ONSTACK(&comm_work.work, pdev_collect_identity_workfn);
+	comm_work.tsm = pdev->tsm;
+
+	queue_work(comm_data->work_queue, &comm_work.work);
+
+	flush_work(&comm_work.work);
+	destroy_work_on_stack(&comm_work.work);
+
+	/* check for device communication error*/
+	if (rmi_pdev_get_state(virt_to_phys(pdev_dsc->rmm_pdev), &state))
+		return -EIO;
+
+	if (state == RMI_PDEV_ERROR)
+		return -EPROTO;
+
+	return 0;
+}
+
+bool cca_pdev_needs_key(struct pci_dev *pdev)
+{
+	enum rmi_pdev_state state;
+	struct cca_host_pdev_dsc *pdev_dsc = to_cca_pdev_dsc(pdev);
+
+	/*
+	 * Consider pdev_get_state failure as need key transition
+	 * and that will result in device communication failure, which
+	 * will handle this error.
+	 */
+	if (rmi_pdev_get_state(virt_to_phys(pdev_dsc->rmm_pdev), &state))
+		return true;
+
+	if (state == RMI_PDEV_NEEDS_KEY)
+		return true;
+	return false;
+}
+
+int cca_pdev_set_public_key(struct pci_dev *pdev)
+{
+	int ret;
+
+	/*
+	 * we now have certificate chain in dsm->cert_chain. Parse that and set
+	 * the pubkey.
+	 */
+	ret = parse_certificate_chain(pdev->tsm);
+	if (ret)
+		return ret;
+
+	ret = pdev_set_public_key(pdev->tsm);
+	if (ret)
+		return ret;
+
+	return submit_pdev_state_transition_work(pdev, RMI_PDEV_READY);
+}
+
 static inline int rmi_pdev_destroy(unsigned long pdev_phys,
-			   unsigned long *rmi_ret)
+		unsigned long *rmi_ret)
 {
 	struct rmi_sro_state *sro __free(sro) =
 		rmi_sro_init(SMC_RMI_PDEV_DESTROY, pdev_phys);
diff --git a/drivers/virt/coco/arm-cca-host/rmi-da.h b/drivers/virt/coco/arm-cca-host/rmi-da.h
index 7d38e548b659..240b2993ae53 100644
--- a/drivers/virt/coco/arm-cca-host/rmi-da.h
+++ b/drivers/virt/coco/arm-cca-host/rmi-da.h
@@ -135,6 +135,9 @@ static inline struct cca_host_comm_data *to_cca_comm_data(struct pci_dev *pdev)
 }
 
 int cca_pdev_create(struct pci_dev *pdev);
+int cca_pdev_collect_identity(struct pci_dev *pdev);
+bool cca_pdev_needs_key(struct pci_dev *pdev);
+int cca_pdev_set_public_key(struct pci_dev *pdev);
 void cca_pdev_stop_and_destroy(struct pci_dev *pdev);
 
 #endif
-- 
2.43.0