1 files changed, 326 insertions, 0 deletions
diff --git a/drivers/firmware/arm_scmi/base.c b/drivers/firmware/arm_scmi/base.c
new file mode 100644
index 0000000000..439d8eb7b6
--- /dev/null
+++ b/drivers/firmware/arm_scmi/base.c
@@ -0,0 +1,326 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Management Interface (SCMI) Base Protocol
+ *
+ * Copyright (C) 2018-2021 ARM Ltd.
+ */
+
+#define pr_fmt(fmt) "SCMI Notifications BASE - " fmt
+
+#include <common.h>
+#include <linux/scmi_protocol.h>
+
+#include "common.h"
+
+#define SCMI_BASE_NUM_SOURCES		1
+#define SCMI_BASE_MAX_CMD_ERR_COUNT	1024
+
+enum scmi_base_protocol_cmd {
+	BASE_DISCOVER_VENDOR = 0x3,
+	BASE_DISCOVER_SUB_VENDOR = 0x4,
+	BASE_DISCOVER_IMPLEMENT_VERSION = 0x5,
+	BASE_DISCOVER_LIST_PROTOCOLS = 0x6,
+	BASE_DISCOVER_AGENT = 0x7,
+	BASE_NOTIFY_ERRORS = 0x8,
+	BASE_SET_DEVICE_PERMISSIONS = 0x9,
+	BASE_SET_PROTOCOL_PERMISSIONS = 0xa,
+	BASE_RESET_AGENT_CONFIGURATION = 0xb,
+};
+
+struct scmi_msg_resp_base_attributes {
+	u8 num_protocols;
+	u8 num_agents;
+	__le16 reserved;
+};
+
+struct scmi_msg_resp_base_discover_agent {
+	__le32 agent_id;
+	u8 name[SCMI_SHORT_NAME_MAX_SIZE];
+};
+
+
+/**
+ * scmi_base_attributes_get() - gets the implementation details
+ *	that are associated with the base protocol.
+ *
+ * @ph: SCMI protocol handle
+ *
+ * Return: 0 on success, else appropriate SCMI error.
+ */
+static int scmi_base_attributes_get(const struct scmi_protocol_handle *ph)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_base_attributes *attr_info;
+	struct scmi_revision_info *rev = ph->get_priv(ph);
+
+	ret = ph->xops->xfer_get_init(ph, PROTOCOL_ATTRIBUTES,
+				      0, sizeof(*attr_info), &t);
+	if (ret)
+		return ret;
+
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret) {
+		attr_info = t->rx.buf;
+		rev->num_protocols = attr_info->num_protocols;
+		rev->num_agents = attr_info->num_agents;
+	}
+
+	ph->xops->xfer_put(ph, t);
+
+	return ret;
+}
+
+/**
+ * scmi_base_vendor_id_get() - gets vendor/subvendor identifier ASCII string.
+ *
+ * @ph: SCMI protocol handle
+ * @sub_vendor: specify true if sub-vendor ID is needed
+ *
+ * Return: 0 on success, else appropriate SCMI error.
+ */
+static int
+scmi_base_vendor_id_get(const struct scmi_protocol_handle *ph, bool sub_vendor)
+{
+	u8 cmd;
+	int ret, size;
+	char *vendor_id;
+	struct scmi_xfer *t;
+	struct scmi_revision_info *rev = ph->get_priv(ph);
+
+
+	if (sub_vendor) {
+		cmd = BASE_DISCOVER_SUB_VENDOR;
+		vendor_id = rev->sub_vendor_id;
+		size = ARRAY_SIZE(rev->sub_vendor_id);
+	} else {
+		cmd = BASE_DISCOVER_VENDOR;
+		vendor_id = rev->vendor_id;
+		size = ARRAY_SIZE(rev->vendor_id);
+	}
+
+	ret = ph->xops->xfer_get_init(ph, cmd, 0, size, &t);
+	if (ret)
+		return ret;
+
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret)
+		strscpy(vendor_id, t->rx.buf, size);
+
+	ph->xops->xfer_put(ph, t);
+
+	return ret;
+}
+
+/**
+ * scmi_base_implementation_version_get() - gets a vendor-specific
+ *	implementation 32-bit version. The format of the version number is
+ *	vendor-specific
+ *
+ * @ph: SCMI protocol handle
+ *
+ * Return: 0 on success, else appropriate SCMI error.
+ */
+static int
+scmi_base_implementation_version_get(const struct scmi_protocol_handle *ph)
+{
+	int ret;
+	__le32 *impl_ver;
+	struct scmi_xfer *t;
+	struct scmi_revision_info *rev = ph->get_priv(ph);
+
+	ret = ph->xops->xfer_get_init(ph, BASE_DISCOVER_IMPLEMENT_VERSION,
+				      0, sizeof(*impl_ver), &t);
+	if (ret)
+		return ret;
+
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret) {
+		impl_ver = t->rx.buf;
+		rev->impl_ver = le32_to_cpu(*impl_ver);
+	}
+
+	ph->xops->xfer_put(ph, t);
+
+	return ret;
+}
+
+/**
+ * scmi_base_implementation_list_get() - gets the list of protocols it is
+ *	OSPM is allowed to access
+ *
+ * @ph: SCMI protocol handle
+ * @protocols_imp: pointer to hold the list of protocol identifiers
+ *
+ * Return: 0 on success, else appropriate SCMI error.
+ */
+static int
+scmi_base_implementation_list_get(const struct scmi_protocol_handle *ph,
+				  u8 *protocols_imp)
+{
+	u8 *list;
+	int ret, loop;
+	struct scmi_xfer *t;
+	__le32 *num_skip, *num_ret;
+	u32 tot_num_ret = 0, loop_num_ret;
+	struct device *dev = ph->dev;
+	struct scmi_revision_info *rev = ph->get_priv(ph);
+
+	ret = ph->xops->xfer_get_init(ph, BASE_DISCOVER_LIST_PROTOCOLS,
+				      sizeof(*num_skip), 0, &t);
+	if (ret)
+		return ret;
+
+	num_skip = t->tx.buf;
+	num_ret = t->rx.buf;
+	list = t->rx.buf + sizeof(*num_ret);
+
+	do {
+		size_t real_list_sz;
+		u32 calc_list_sz;
+
+		/* Set the number of protocols to be skipped/already read */
+		*num_skip = cpu_to_le32(tot_num_ret);
+
+		ret = ph->xops->do_xfer(ph, t);
+		if (ret)
+			break;
+
+		loop_num_ret = le32_to_cpu(*num_ret);
+		if (!loop_num_ret)
+			break;
+
+		if (loop_num_ret > rev->num_protocols - tot_num_ret) {
+			dev_err(dev,
+				"No. Returned protocols > Total protocols.\n");
+			break;
+		}
+
+		if (t->rx.len < (sizeof(u32) * 2)) {
+			dev_err(dev, "Truncated reply - rx.len:%zd\n",
+				t->rx.len);
+			ret = -EPROTO;
+			break;
+		}
+
+		real_list_sz = t->rx.len - sizeof(u32);
+		calc_list_sz = (1 + (loop_num_ret - 1) / sizeof(u32)) *
+				sizeof(u32);
+		if (calc_list_sz != real_list_sz) {
+			dev_warn(dev,
+				 "Malformed reply - real_sz:%zd  calc_sz:%u  (loop_num_ret:%d)\n",
+				 real_list_sz, calc_list_sz, loop_num_ret);
+			/*
+			 * Bail out if the expected list size is bigger than the
+			 * total payload size of the received reply.
+			 */
+			if (calc_list_sz > real_list_sz) {
+				ret = -EPROTO;
+				break;
+			}
+		}
+
+		for (loop = 0; loop < loop_num_ret; loop++)
+			protocols_imp[tot_num_ret + loop] = *(list + loop);
+
+		tot_num_ret += loop_num_ret;
+
+		ph->xops->reset_rx_to_maxsz(ph, t);
+	} while (tot_num_ret < rev->num_protocols);
+
+	ph->xops->xfer_put(ph, t);
+
+	return ret;
+}
+
+/**
+ * scmi_base_discover_agent_get() - discover the name of an agent
+ *
+ * @ph: SCMI protocol handle
+ * @id: Agent identifier
+ * @name: Agent identifier ASCII string
+ *
+ * An agent id of 0 is reserved to identify the platform itself.
+ * Generally operating system is represented as "OSPM"
+ *
+ * Return: 0 on success, else appropriate SCMI error.
+ */
+static int scmi_base_discover_agent_get(const struct scmi_protocol_handle *ph,
+					int id, char *name)
+{
+	int ret;
+	struct scmi_msg_resp_base_discover_agent *agent_info;
+	struct scmi_xfer *t;
+
+	ret = ph->xops->xfer_get_init(ph, BASE_DISCOVER_AGENT,
+				      sizeof(__le32), sizeof(*agent_info), &t);
+	if (ret)
+		return ret;
+
+	put_unaligned_le32(id, t->tx.buf);
+
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret) {
+		agent_info = t->rx.buf;
+		strscpy(name, agent_info->name, SCMI_SHORT_NAME_MAX_SIZE);
+	}
+
+	ph->xops->xfer_put(ph, t);
+
+	return ret;
+}
+
+static int scmi_base_protocol_init(const struct scmi_protocol_handle *ph)
+{
+	int id, ret;
+	u8 *prot_imp;
+	u32 version;
+	char name[SCMI_SHORT_NAME_MAX_SIZE];
+	struct device *dev = ph->dev;
+	struct scmi_revision_info *rev = scmi_revision_area_get(ph);
+
+	ret = ph->xops->version_get(ph, &version);
+	if (ret)
+		return ret;
+
+	rev->major_ver = PROTOCOL_REV_MAJOR(version),
+	rev->minor_ver = PROTOCOL_REV_MINOR(version);
+	ph->set_priv(ph, rev);
+
+	ret = scmi_base_attributes_get(ph);
+	if (ret)
+		return ret;
+
+	prot_imp = devm_kcalloc(dev, rev->num_protocols, sizeof(u8),
+				GFP_KERNEL);
+	if (!prot_imp)
+		return -ENOMEM;
+
+	scmi_base_vendor_id_get(ph, false);
+	scmi_base_vendor_id_get(ph, true);
+	scmi_base_implementation_version_get(ph);
+	scmi_base_implementation_list_get(ph, prot_imp);
+
+	scmi_setup_protocol_implemented(ph, prot_imp);
+
+	dev_info(dev, "SCMI Protocol v%d.%d '%s:%s' Firmware version 0x%x\n",
+		 rev->major_ver, rev->minor_ver, rev->vendor_id,
+		 rev->sub_vendor_id, rev->impl_ver);
+	dev_dbg(dev, "Found %d protocol(s) %d agent(s)\n", rev->num_protocols,
+		rev->num_agents);
+
+	for (id = 0; id < rev->num_agents; id++) {
+		scmi_base_discover_agent_get(ph, id, name);
+		dev_dbg(dev, "Agent %d: %s\n", id, name);
+	}
+
+	return 0;
+}
+
+static const struct scmi_protocol scmi_base = {
+	.id = SCMI_PROTOCOL_BASE,
+	.instance_init = &scmi_base_protocol_init,
+	.ops = NULL,
+};
+
+DEFINE_SCMI_PROTOCOL_REGISTER(base, scmi_base)