[RFC 3/7] firmware: arm_scmi: Add QCOM vendor protocol

Sibi Sankar
2024-01-17T17:35:41Z

From: Shivnandan Kumar <quic_kshivnan@quicinc.com>

SCMI QCOM vendor protocol provides interface to communicate with SCMI
controller and enable vendor specific features like bus scaling capable
of running on it.

Signed-off-by: Shivnandan Kumar <quic_kshivnan@quicinc.com>
Co-developed-by: Ramakrishna Gottimukkula <quic_rgottimu@quicinc.com>
Signed-off-by: Ramakrishna Gottimukkula <quic_rgottimu@quicinc.com>
Co-developed-by: Amir Vajid <avajid@quicinc.com>
Signed-off-by: Amir Vajid <avajid@quicinc.com>
Co-developed-by: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com>
---
drivers/firmware/arm_scmi/Kconfig | 11 ++
drivers/firmware/arm_scmi/Makefile | 1 +
drivers/firmware/arm_scmi/qcom_scmi_vendor.c | 160 +++++++++++++++++++
include/linux/qcom_scmi_vendor.h | 36 +++++
4 files changed, 208 insertions(+)
create mode 100644 drivers/firmware/arm_scmi/qcom_scmi_vendor.c
create mode 100644 include/linux/qcom_scmi_vendor.h

diff --git a/drivers/firmware/arm_scmi/Kconfig b/drivers/firmware/arm_scmi/Kconfig
index aa5842be19b2..86b5d6c18ec4 100644
--- a/drivers/firmware/arm_scmi/Kconfig
+++ b/drivers/firmware/arm_scmi/Kconfig
@@ -180,4 +180,15 @@ config ARM_SCMI_POWER_CONTROL
called scmi_power_control. Note this may needed early in boot to catch
early shutdown/reboot SCMI requests.

+config QCOM_SCMI_VENDOR_PROTOCOL
+ tristate "Qualcomm Technologies, Inc. Qcom SCMI vendor Protocol"
+ depends on ARM || ARM64 || COMPILE_TEST
+ depends on ARM_SCMI_PROTOCOL
+ help
+ The SCMI QCOM vendor protocol provides interface to communicate with SCMI
+ controller and enable vendor specific features like bus scaling.
+
+ This driver defines the commands or message ID's used for this
+ communication and also exposes the ops used by the clients.
+
endmenu
diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile
index a7bc4796519c..eaeb788b93c6 100644
--- a/drivers/firmware/arm_scmi/Makefile
+++ b/drivers/firmware/arm_scmi/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-core.o
obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-module.o

obj-$(CONFIG_ARM_SCMI_POWER_CONTROL) += scmi_power_control.o
+obj-$(CONFIG_QCOM_SCMI_VENDOR_PROTOCOL) += qcom_scmi_vendor.o

ifeq ($(CONFIG_THUMB2_KERNEL)$(CONFIG_CC_IS_CLANG),yy)
# The use of R7 in the SMCCC conflicts with the compiler's use of R7 as a frame
diff --git a/drivers/firmware/arm_scmi/qcom_scmi_vendor.c b/drivers/firmware/arm_scmi/qcom_scmi_vendor.c
new file mode 100644
index 000000000000..878b99f0d1ef
--- /dev/null
+++ b/drivers/firmware/arm_scmi/qcom_scmi_vendor.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2024, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/qcom_scmi_vendor.h>
+
+#include "common.h"
+
+#define EXTENDED_MSG_ID 0
+#define SCMI_MAX_TX_RX_SIZE 128
+#define PROTOCOL_PAYLOAD_SIZE 16
+#define SET_PARAM 0x10
+#define GET_PARAM 0x11
+#define START_ACTIVITY 0x12
+#define STOP_ACTIVITY 0x13
+
+static int qcom_scmi_set_param(const struct scmi_protocol_handle *ph, void *buf, u64 algo_str,
+ u32 param_id, size_t size)
+{
+ int ret = -EINVAL;
+ struct scmi_xfer *t;
+ u32 *msg;
+
+ if (!ph || !ph->xops)
+ return ret;
+
+ ret = ph->xops->xfer_get_init(ph, SET_PARAM, size + PROTOCOL_PAYLOAD_SIZE,
+ SCMI_MAX_TX_RX_SIZE, &t);
+ if (ret)
+ return ret;
+
+ msg = t->tx.buf;
+ *msg++ = cpu_to_le32(EXTENDED_MSG_ID);
+ *msg++ = cpu_to_le32(algo_str & GENMASK(31, 0));
+ *msg++ = cpu_to_le32((algo_str & GENMASK(63, 32)) >> 32);
+ *msg++ = cpu_to_le32(param_id);
+ memcpy(msg, buf, size);
+ ret = ph->xops->do_xfer(ph, t);
+ ph->xops->xfer_put(ph, t);
+
+ return ret;
+}
+
+static int qcom_scmi_get_param(const struct scmi_protocol_handle *ph, void *buf, u64 algo_str,
+ u32 param_id, size_t tx_size, size_t rx_size)
+{
+ int ret = -EINVAL;
+ struct scmi_xfer *t;
+ u32 *msg;
+
+ if (!ph || !ph->xops || !buf)
+ return ret;
+
+ ret = ph->xops->xfer_get_init(ph, GET_PARAM, tx_size + PROTOCOL_PAYLOAD_SIZE,
+ SCMI_MAX_TX_RX_SIZE, &t);
+ if (ret)
+ return ret;
+
+ msg = t->tx.buf;
+ *msg++ = cpu_to_le32(EXTENDED_MSG_ID);
+ *msg++ = cpu_to_le32(algo_str & GENMASK(31, 0));
+ *msg++ = cpu_to_le32((algo_str & GENMASK(63, 32)) >> 32);
+ *msg++ = cpu_to_le32(param_id);
+ memcpy(msg, buf, tx_size);
+ ret = ph->xops->do_xfer(ph, t);
+ if (t->rx.len > rx_size) {
+ pr_err("SCMI received buffer size %zu is more than expected size %zu\n",
+ t->rx.len, rx_size);
+ return -EMSGSIZE;
+ }
+ memcpy(buf, t->rx.buf, t->rx.len);
+ ph->xops->xfer_put(ph, t);
+
+ return ret;
+}
+
+static int qcom_scmi_start_activity(const struct scmi_protocol_handle *ph,
+ void *buf, u64 algo_str, u32 param_id, size_t size)
+{
+ int ret = -EINVAL;
+ struct scmi_xfer *t;
+ u32 *msg;
+
+ if (!ph || !ph->xops)
+ return ret;
+
+ ret = ph->xops->xfer_get_init(ph, START_ACTIVITY, size + PROTOCOL_PAYLOAD_SIZE,
+ SCMI_MAX_TX_RX_SIZE, &t);
+ if (ret)
+ return ret;
+
+ msg = t->tx.buf;
+ *msg++ = cpu_to_le32(EXTENDED_MSG_ID);
+ *msg++ = cpu_to_le32(algo_str & GENMASK(31, 0));
+ *msg++ = cpu_to_le32((algo_str & GENMASK(63, 32)) >> 32);
+ *msg++ = cpu_to_le32(param_id);
+ memcpy(msg, buf, size);
+ ret = ph->xops->do_xfer(ph, t);
+ ph->xops->xfer_put(ph, t);
+
+ return ret;
+}
+
+static int qcom_scmi_stop_activity(const struct scmi_protocol_handle *ph, void *buf, u64 algo_str,
+ u32 param_id, size_t size)
+{
+ int ret = -EINVAL;
+ struct scmi_xfer *t;
+ u32 *msg;
+
+ if (!ph || !ph->xops)
+ return ret;
+
+ ret = ph->xops->xfer_get_init(ph, STOP_ACTIVITY, size + PROTOCOL_PAYLOAD_SIZE,
+ SCMI_MAX_TX_RX_SIZE, &t);
+ if (ret)
+ return ret;
+
+ msg = t->tx.buf;
+ *msg++ = cpu_to_le32(EXTENDED_MSG_ID);
+ *msg++ = cpu_to_le32(algo_str & GENMASK(31, 0));
+ *msg++ = cpu_to_le32((algo_str & GENMASK(63, 32)) >> 32);
+ *msg++ = cpu_to_le32(param_id);
+ memcpy(msg, buf, size);
+ ret = ph->xops->do_xfer(ph, t);
+ ph->xops->xfer_put(ph, t);
+
+ return ret;
+}
+
+static struct qcom_scmi_vendor_ops qcom_proto_ops = {
+ .set_param = qcom_scmi_set_param,
+ .get_param = qcom_scmi_get_param,
+ .start_activity = qcom_scmi_start_activity,
+ .stop_activity = qcom_scmi_stop_activity,
+};
+
+static int qcom_scmi_vendor_protocol_init(const struct scmi_protocol_handle *ph)
+{
+ u32 version;
+
+ ph->xops->version_get(ph, &version);
+
+ dev_info(ph->dev, "qcom scmi version %d.%d\n",
+ PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
+
+ return 0;
+}
+
+static const struct scmi_protocol qcom_scmi_vendor = {
+ .id = QCOM_SCMI_VENDOR_PROTOCOL,
+ .owner = THIS_MODULE,
+ .instance_init = &qcom_scmi_vendor_protocol_init,
+ .ops = &qcom_proto_ops,
+};
+module_scmi_protocol(qcom_scmi_vendor);
+
+MODULE_DESCRIPTION("QTI SCMI vendor protocol");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/qcom_scmi_vendor.h b/include/linux/qcom_scmi_vendor.h
new file mode 100644
index 000000000000..bde57bb18367
--- /dev/null
+++ b/include/linux/qcom_scmi_vendor.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * QTI SCMI vendor protocol's header
+ *
+ * Copyright (c) 2024, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef _QCOM_SCMI_VENDOR_H
+#define _QCOM_SCMI_VENDOR_H
+
+#include <linux/bitfield.h>
+#include <linux/device.h>
+#include <linux/types.h>
+
+#define QCOM_SCMI_VENDOR_PROTOCOL 0x80
+
+struct scmi_protocol_handle;
+extern struct scmi_device *get_qcom_scmi_device(void);
+
+/**
+ * struct qcom_scmi_vendor_ops - represents the various operations provided
+ * by qcom scmi vendor protocol
+ */
+struct qcom_scmi_vendor_ops {
+ int (*set_param)(const struct scmi_protocol_handle *ph, void *buf, u64 algo_str,
+ u32 param_id, size_t size);
+ int (*get_param)(const struct scmi_protocol_handle *ph, void *buf, u64 algo_str,
+ u32 param_id, size_t tx_size, size_t rx_size);
+ int (*start_activity)(const struct scmi_protocol_handle *ph, void *buf, u64 algo_str,
+ u32 param_id, size_t size);
+ int (*stop_activity)(const struct scmi_protocol_handle *ph, void *buf, u64 algo_str,
+ u32 param_id, size_t size);
+};
+
+#endif /* _QCOM_SCMI_VENDOR_H */
+
--
2.34.1