chip/mt8192_scp: support hostcmd over IPI

BRANCH=none
BUG=b:146213943
BUG=b:160382789
TEST=make BOARD=asurada_scp

Signed-off-by: Tzung-Bi Shih <tzungbi@chromium.org>
Change-Id: Ifc2cfc127213c6951eab1aea733a6e90e3594827
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2299601
Reviewed-by: Eric Yilun Lin <yllin@chromium.org>

4 files changed, 147 insertions, 0 deletions

diff --git a/chip/mt8192_scp/build.mk b/chip/mt8192_scp/build.mk
index 277b2d8f6d..86ba6a499c 100644
--- a/chip/mt8192_scp/build.mk
+++ b/chip/mt8192_scp/build.mk
@@ -23,3 +23,4 @@ endif
 chip-$(CONFIG_COMMON_TIMER)+=hrtimer.o
 chip-$(CONFIG_IPI)+=ipi.o ipi_table.o
 chip-$(CONFIG_WATCHDOG)+=watchdog.o
+chip-$(HAS_TASK_HOSTCMD)+=hostcmd.o
diff --git a/chip/mt8192_scp/hostcmd.c b/chip/mt8192_scp/hostcmd.c
new file mode 100644
index 0000000000..42a463ee56
--- /dev/null
+++ b/chip/mt8192_scp/hostcmd.c
@@ -0,0 +1,128 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "console.h"
+#include "host_command.h"
+#include "ipi_chip.h"
+#include "util.h"
+
+#define CPRINTF(format, args...) cprintf(CC_IPI, format, ##args)
+#define CPRINTS(format, args...) cprints(CC_IPI, format, ##args)
+
+#define HOSTCMD_MAX_REQUEST_SIZE CONFIG_IPC_SHARED_OBJ_BUF_SIZE
+/* Reserve 1 extra byte for HOSTCMD_TYPE and 3 bytes for padding. */
+#define HOSTCMD_MAX_RESPONSE_SIZE (CONFIG_IPC_SHARED_OBJ_BUF_SIZE - 4)
+#define HOSTCMD_TYPE_HOSTCMD 1
+#define HOSTCMD_TYPE_HOSTEVENT 2
+
+/*
+ * hostcmd and hostevent share the same IPI ID, and use first byte type to
+ * indicate its type.
+ */
+static struct hostcmd_data {
+	const uint8_t type;
+	/* To be compatible with CONFIG_HOSTCMD_ALIGNED */
+	uint8_t response[HOSTCMD_MAX_RESPONSE_SIZE] __aligned(4);
+} hc_cmd_obj = { .type = HOSTCMD_TYPE_HOSTCMD };
+BUILD_ASSERT(sizeof(struct hostcmd_data) == CONFIG_IPC_SHARED_OBJ_BUF_SIZE);
+
+/* Size of the rpmsg device name, should sync across kernel and EC. */
+#define RPMSG_NAME_SIZE 32
+
+/*
+ * The layout of name service message.
+ * This should sync across kernel and EC.
+ */
+struct rpmsg_ns_msg {
+	/* Name of the corresponding rpmsg_driver. */
+	char name[RPMSG_NAME_SIZE];
+	/* IPC ID */
+	uint32_t addr;
+};
+
+static void hostcmd_send_response_packet(struct host_packet *pkt)
+{
+	int ret;
+
+	ret = ipi_send(SCP_IPI_HOST_COMMAND, &hc_cmd_obj,
+		       pkt->response_size +
+			       offsetof(struct hostcmd_data, response),
+		       1);
+	if (ret)
+		CPRINTS("failed to %s(), ret=%d", __func__, ret);
+}
+
+static void hostcmd_handler(int32_t id, void *buf, uint32_t len)
+{
+	static struct host_packet packet;
+	uint8_t *in_msg = buf;
+	struct ec_host_request *r = (struct ec_host_request *)in_msg;
+	int i;
+
+	if (in_msg[0] != EC_HOST_REQUEST_VERSION) {
+		CPRINTS("ERROR: Protocol V2 is not supported!");
+		CPRINTF("in_msg=[");
+		for (i = 0; i < len; i++)
+			CPRINTF("%02x ", in_msg[i]);
+		CPRINTF("]\n");
+		return;
+	}
+
+	/* Protocol version 3 */
+
+	packet.send_response = hostcmd_send_response_packet;
+
+	/*
+	 * Just assign the buffer to request, host_packet_receive
+	 * handles the buffer copy.
+	 */
+	packet.request = (void *)r;
+	packet.request_temp = NULL;
+	packet.request_max = HOSTCMD_MAX_REQUEST_SIZE;
+	packet.request_size = host_request_expected_size(r);
+
+	packet.response = hc_cmd_obj.response;
+	/* Reserve space for the preamble and trailing byte */
+	packet.response_max = HOSTCMD_MAX_RESPONSE_SIZE;
+	packet.response_size = 0;
+
+	packet.driver_result = EC_RES_SUCCESS;
+
+	host_packet_receive(&packet);
+}
+DECLARE_IPI(SCP_IPI_HOST_COMMAND, hostcmd_handler, 0);
+
+/*
+ * Get protocol information
+ */
+static enum ec_status hostcmd_get_protocol_info(struct host_cmd_handler_args *args)
+{
+	struct ec_response_get_protocol_info *r = args->response;
+
+	memset(r, 0, sizeof(*r));
+	r->protocol_versions |= BIT(3);
+	r->max_request_packet_size = HOSTCMD_MAX_REQUEST_SIZE;
+	r->max_response_packet_size = HOSTCMD_MAX_RESPONSE_SIZE;
+
+	args->response_size = sizeof(*r);
+
+	return EC_SUCCESS;
+}
+DECLARE_HOST_COMMAND(EC_CMD_GET_PROTOCOL_INFO, hostcmd_get_protocol_info,
+		     EC_VER_MASK(0));
+
+void hostcmd_init(void)
+{
+	int ret;
+	struct rpmsg_ns_msg ns_msg;
+
+	if (IS_ENABLED(CONFIG_RPMSG_NAME_SERVICE)) {
+		ns_msg.addr = SCP_IPI_HOST_COMMAND;
+		strncpy(ns_msg.name, "cros-ec-rpmsg", RPMSG_NAME_SIZE);
+		ret = ipi_send(SCP_IPI_NS_SERVICE, &ns_msg, sizeof(ns_msg), 1);
+		if (ret)
+			CPRINTS("Failed to announce host command channel");
+	}
+}
diff --git a/chip/mt8192_scp/hostcmd.h b/chip/mt8192_scp/hostcmd.h
new file mode 100644
index 0000000000..b93f1e725d
--- /dev/null
+++ b/chip/mt8192_scp/hostcmd.h
@@ -0,0 +1,12 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef __CROS_EC_HOSTCMD_H
+#define __CROS_EC_HOSTCMD_H
+
+/* Initialize hostcmd. */
+void hostcmd_init(void);
+
+#endif /* __CROS_EC_HOSTCMD_H */
diff --git a/chip/mt8192_scp/ipi.c b/chip/mt8192_scp/ipi.c
index cc78c7878c..1f50b092f7 100644
--- a/chip/mt8192_scp/ipi.c
+++ b/chip/mt8192_scp/ipi.c
@@ -7,6 +7,7 @@
 #include "common.h"
 #include "console.h"
 #include "hooks.h"
+#include "hostcmd.h"
 #include "ipi_chip.h"
 #include "registers.h"
 #include "system.h"
@@ -52,6 +53,9 @@ static int ipi_is_busy(void)
 
 static void ipi_wake_ap(int32_t id)
 {
+	if (id >= IPI_COUNT)
+		return;
+
 	if (*ipi_wakeup_table[id])
 		SCP_SCP2SPM_IPC_SET = IPC_SCP2HOST;
 }
@@ -135,6 +139,8 @@ static void ipi_enable_deferred(void)
 		return;
 	}
 
+	hostcmd_init();
+
 	task_enable_irq(SCP_IRQ_GIPC_IN0);
 }
 DECLARE_DEFERRED(ipi_enable_deferred);