core/pldm: Register OPAL_IPMI_SEND/RECV calls back

backend apis to support partially:
OPAL_IPMI_SEND: send an IPMI message to the service processor
OPAL_IPMI_RECV: read an ipmi message of type ``ipmi_msg`` from ipmi message
queue ``msgq`` into host OS structure ``opal_ipmi_msg``

Signed-off-by: Christophe Lombard <clombard@linux.ibm.com>
Signed-off-by: Reza Arbab <arbab@linux.ibm.com>

3 files changed, 304 insertions, 1 deletions

diff --git a/core/pldm/Makefile.inc b/core/pldm/Makefile.inc
index 14aa105..4484fac 100644
--- a/core/pldm/Makefile.inc
+++ b/core/pldm/Makefile.inc
@@ -11,7 +11,7 @@ PLDM_OBJS = pldm-mctp.o pldm-responder.o pldm-requester.o
 PLDM_OBJS += pldm-base-requests.o pldm-platform-requests.o
 PLDM_OBJS += pldm-bios-requests.o pldm-fru-requests.o
 PLDM_OBJS += pldm-file-io-requests.o pldm-lid-files.o
-PLDM_OBJS += pldm-watchdog.o pldm-rtc.o
+PLDM_OBJS += pldm-watchdog.o pldm-rtc.o pldm-opal.o
 
 PLDM = $(PLDM_DIR)/built-in.a
 $(PLDM): $(PLDM_OBJS:%=$(PLDM_DIR)/%)
diff --git a/core/pldm/pldm-opal.c b/core/pldm/pldm-opal.c
new file mode 100644
index 0000000..c995095
--- /dev/null
+++ b/core/pldm/pldm-opal.c
@@ -0,0 +1,298 @@
+// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+// Copyright 2022 IBM Corp.
+
+#define pr_fmt(fmt) "PLDM: " fmt
+
+#include <stdlib.h>
+#include <string.h>
+#include <device.h>
+#include <ipmi.h>
+#include <opal.h>
+#include <lock.h>
+#include <timebase.h>
+#include <ccan/list/list.h>
+#include "pldm.h"
+
+#define BMC_VERSION_LENGTH 100
+
+/*
+ * Response data from IPMI Get device ID command (As defined in
+ * Section 20.1 Get Device ID Command - IPMI standard spec).
+ */
+struct ipmi_dev_id {
+	uint8_t dev_id;
+	uint8_t dev_revision;
+	uint8_t fw_rev1;
+	uint8_t fw_rev2;
+	uint8_t ipmi_ver;
+	uint8_t add_dev_support;
+	uint8_t manufactur_id[3];
+	uint8_t product_id[2];
+	uint8_t aux_fw_rev[4];
+};
+
+static struct lock msgq_lock = LOCK_UNLOCKED;
+static struct list_head msgq = LIST_HEAD_INIT(msgq);
+uint64_t opal_event_ipmi_recv;
+
+static void opal_send_complete(struct ipmi_msg *msg)
+{
+	lock(&msgq_lock);
+	list_add_tail(&msgq, &msg->link);
+	opal_update_pending_evt(opal_event_ipmi_recv,
+			opal_event_ipmi_recv);
+	unlock(&msgq_lock);
+}
+
+#define GUID_SIZE 16
+
+static int opal_get_tid_req(struct opal_ipmi_msg *opal_ipmi_msg,
+			    uint64_t msg_len __unused)
+{
+	struct ipmi_msg *opal_ipmi_response = NULL;
+	uint8_t guid[GUID_SIZE];
+	int bmc_tid;
+
+	opal_ipmi_response = zalloc(sizeof(struct ipmi_msg) + GUID_SIZE);
+	opal_ipmi_response->netfn = IPMI_NETFN_RETURN_CODE(opal_ipmi_msg->netfn);
+	opal_ipmi_response->cmd = opal_ipmi_msg->cmd;
+
+	memset(&guid, 0, GUID_SIZE);
+
+	/* First byte of guid contains bmc tid */
+	bmc_tid = pldm_base_get_bmc_tid();
+	if (bmc_tid == -1) {
+		opal_ipmi_response->resp_size = 0;
+		opal_ipmi_response->cc = IPMI_ERR_UNSPECIFIED;
+		goto out;
+	}
+
+	guid[0] = (uint8_t)bmc_tid;
+	memcpy(opal_ipmi_response->data, guid, GUID_SIZE);
+
+	opal_ipmi_response->resp_size = GUID_SIZE;
+	opal_ipmi_response->cc = IPMI_CC_NO_ERROR;
+
+out:
+	opal_send_complete(opal_ipmi_response);
+	return OPAL_SUCCESS;
+}
+
+static int parse_bmc_version(uint8_t *bmc_version,
+			     struct ipmi_dev_id *devid)
+{
+	uint8_t *ptr;
+	uint8_t temp;
+
+	prlog(PR_TRACE, "%s - bmc version: %s len=%d\n", __func__,
+			bmc_version, (int)strlen(bmc_version));
+
+	/*
+	 * parse bmc version string to find fw_rev1 and fw_rev2
+	 * Firmware Name is in format :
+	 * fw1030.00-2.8-1030.2233.20220819a (NL1030_007)
+	 * so fw_rev1 = 10
+	 * fw_rev2 = 20
+	 * aux_fw_rev = "007"
+	 */
+	ptr = strstr(bmc_version, "NL");
+	if (ptr == NULL || strlen(ptr) < 8)
+		return OPAL_PARAMETER;
+
+	ptr += 2;
+	/*
+	 * Convert first two byte to
+	 * fw_rev1 and net 2byte to fw_rev2
+	 */
+	temp = ptr[2];
+	ptr[2] = '\0';
+	devid->fw_rev1 = (uint8_t)atoi(ptr);
+	ptr += 2;
+	ptr[0] = temp;
+
+	temp = ptr[2];
+	ptr[2] = '\0';
+	devid->fw_rev2 = (uint8_t)atoi(ptr);
+	ptr += 2;
+	ptr[0] = temp;
+
+	/* Aux version is truncated to 4 char only */
+	if (*ptr == '_')
+		strncpy(devid->aux_fw_rev, ptr + 1, 3);
+
+	prlog(PR_TRACE, "BMC Version major->%d minor->%d aux->%.4s\n",
+			devid->fw_rev1, devid->fw_rev2, devid->aux_fw_rev);
+
+	return OPAL_SUCCESS;
+}
+
+static int opal_get_bmc_info(struct opal_ipmi_msg *opal_ipmi_msg,
+			     uint64_t msg_len __unused)
+{
+	struct ipmi_msg *opal_ipmi_response = NULL;
+	char bmc_version[BMC_VERSION_LENGTH];
+	struct ipmi_dev_id devid;
+	int rc;
+
+	opal_ipmi_response = zalloc(sizeof(struct ipmi_msg) +
+				    sizeof(struct ipmi_dev_id));
+	opal_ipmi_response->resp_size = sizeof(struct ipmi_dev_id);
+	opal_ipmi_response->netfn = IPMI_NETFN_RETURN_CODE(opal_ipmi_msg->netfn);
+	opal_ipmi_response->cmd = opal_ipmi_msg->cmd;
+	opal_ipmi_response->cc = IPMI_CC_NO_ERROR;
+
+	memset(&devid, 0, sizeof(devid));
+	devid.ipmi_ver = OPAL_IPMI_MSG_FORMAT_VERSION_1;
+
+	/* retrieve bmc version */
+	rc = pldm_fru_get_bmc_version(bmc_version, BMC_VERSION_LENGTH);
+	if (rc) {
+		opal_ipmi_response->resp_size = 0;
+		opal_ipmi_response->cc = IPMI_ERR_UNSPECIFIED;
+		goto out;
+	}
+
+	/* parse the bmc version */
+	rc = parse_bmc_version(bmc_version, &devid);
+	if (rc) {
+		prlog(PR_ERR, "%s: Failed to parse BMC version, bmc version: %s\n",
+				__func__, bmc_version);
+		opal_ipmi_response->resp_size = 0;
+		opal_ipmi_response->cc = IPMI_ERR_UNSPECIFIED;
+		goto out;
+	}
+
+	memcpy(opal_ipmi_response->data, &devid, sizeof(devid));
+
+out:
+	opal_send_complete(opal_ipmi_response);
+	return OPAL_SUCCESS;
+}
+
+static int64_t opal_ipmi_send(uint64_t interface __unused,
+			      struct opal_ipmi_msg *opal_ipmi_msg,
+			      uint64_t msg_len)
+{
+	int16_t ipmi_code;
+
+	if (opal_ipmi_msg->version != OPAL_IPMI_MSG_FORMAT_VERSION_1) {
+		prerror("OPAL IPMI: Incorrect version\n");
+		return OPAL_UNSUPPORTED;
+	}
+
+	msg_len -= sizeof(struct opal_ipmi_msg);
+	if (msg_len > IPMI_MAX_REQ_SIZE) {
+		prerror("OPAL IPMI: Invalid request length\n");
+		return OPAL_PARAMETER;
+	}
+
+	ipmi_code = IPMI_CODE(opal_ipmi_msg->netfn >> 2, opal_ipmi_msg->cmd);
+	if ((ipmi_code == IPMI_CHASSIS_GET_SYS_BOOT_OPT_CMD) ||
+	    (opal_ipmi_msg->cmd == IPMI_CODE(opal_ipmi_msg->netfn >> 2, 0x1a)) ||
+	    (opal_ipmi_msg->cmd == IPMI_CODE(opal_ipmi_msg->netfn >> 2, 0x42))) {
+		prerror("OPAL IPMI: Command not supported, code: %d, "
+			"cmd: 0x%x netfn: 0x%x\n",
+			ipmi_code, opal_ipmi_msg->cmd, opal_ipmi_msg->netfn >> 2);
+		return OPAL_UNSUPPORTED;
+	}
+
+	prlog(PR_TRACE, "%s - cmd: 0x%02x netfn: 0x%02x len: 0x%02llx\n",
+			__func__, opal_ipmi_msg->cmd, opal_ipmi_msg->netfn >> 2,
+			msg_len);
+
+	switch (opal_ipmi_msg->cmd) {
+	case IPMI_GET_DEVICE_ID_CMD:
+		return opal_get_bmc_info(opal_ipmi_msg, msg_len);
+
+	case IPMI_GET_DEVICE_GUID_CMD:
+		return opal_get_tid_req(opal_ipmi_msg, msg_len);
+	}
+
+	prerror("OPAL IPMI: Command not supported, cmd: 0x%x netfn: 0x%x\n",
+		 opal_ipmi_msg->cmd, opal_ipmi_msg->netfn >> 2);
+
+	return OPAL_UNSUPPORTED;
+}
+
+static int64_t opal_ipmi_recv(uint64_t interface,
+			      struct opal_ipmi_msg *opal_ipmi_msg,
+			      __be64 *msg_len)
+{
+	struct ipmi_msg *msg;
+	int64_t rc;
+
+	lock(&msgq_lock);
+	msg = list_top(&msgq, struct ipmi_msg, link);
+
+	if (!msg) {
+		rc = OPAL_EMPTY;
+		goto out_unlock;
+	}
+
+	if (opal_ipmi_msg->version != OPAL_IPMI_MSG_FORMAT_VERSION_1) {
+		prerror("OPAL IPMI: Incorrect version\n");
+		rc = OPAL_UNSUPPORTED;
+		goto out_del_msg;
+	}
+
+	if (interface != IPMI_DEFAULT_INTERFACE) {
+		prerror("IPMI: Invalid interface 0x%llx in %s\n", interface, __func__);
+		rc = OPAL_PARAMETER;
+		goto out_del_msg;
+	}
+
+	if (be64_to_cpu(*msg_len) - sizeof(struct opal_ipmi_msg) < msg->resp_size + 1) {
+		rc = OPAL_RESOURCE;
+		goto out_del_msg;
+	}
+
+	list_del(&msg->link);
+	if (list_empty(&msgq))
+		opal_update_pending_evt(opal_event_ipmi_recv, 0);
+	unlock(&msgq_lock);
+
+	opal_ipmi_msg->cmd = msg->cmd;
+	opal_ipmi_msg->netfn = msg->netfn;
+	opal_ipmi_msg->data[0] = msg->cc;
+	memcpy(&opal_ipmi_msg->data[1], msg->data, msg->resp_size);
+
+	prlog(PR_TRACE, "%s - cmd: 0x%02x netfn: 0x%02x resp_size: 0x%02x\n",
+			__func__, msg->cmd, msg->netfn >> 2, msg->resp_size);
+
+	/* Add one as the completion code is returned in the message data */
+	*msg_len = cpu_to_be64(msg->resp_size + sizeof(struct opal_ipmi_msg) + 1);
+	free(msg);
+
+	return OPAL_SUCCESS;
+
+out_del_msg:
+	list_del(&msg->link);
+	if (list_empty(&msgq))
+		opal_update_pending_evt(opal_event_ipmi_recv, 0);
+	free(msg);
+
+out_unlock:
+	unlock(&msgq_lock);
+	return rc;
+}
+
+void pldm_opal_init(void)
+{
+	struct dt_node *opal_ipmi, *opal_event = NULL;
+
+	opal_ipmi = dt_new(opal_node, "ipmi");
+	dt_add_property_strings(opal_ipmi, "compatible", "ibm,opal-ipmi");
+	dt_add_property_cells(opal_ipmi, "ibm,ipmi-interface-id",
+			      IPMI_DEFAULT_INTERFACE);
+	opal_event_ipmi_recv = opal_dynamic_event_alloc();
+	dt_add_property_cells(opal_ipmi, "interrupts",
+			      ilog2(opal_event_ipmi_recv));
+
+	opal_event = dt_find_by_name(opal_node, "event");
+	if (opal_event)
+		dt_add_property_cells(opal_ipmi, "interrupt-parent",
+				      opal_event->phandle);
+
+	opal_register(OPAL_IPMI_SEND, opal_ipmi_send, 3);
+	opal_register(OPAL_IPMI_RECV, opal_ipmi_recv, 3);
+}
diff --git a/include/pldm.h b/include/pldm.h
index 7f944e7..54c9bd4 100644
--- a/include/pldm.h
+++ b/include/pldm.h
@@ -70,4 +70,9 @@ int pldm_platform_send_progress_state_change(
  */
 void pldm_rtc_init(void);
 
+/**
+ * Register ipmi host interface access callbacks
+ */
+void pldm_opal_init(void);
+
 #endif /* __PLDM_H__ */