Introduce SCP power management abstraction
This patch introduces an additional layer of abstraction between
CSS power management hooks and the SCPI driver. A new set of APIs
are introduced in order to abstract out power management operations
from underlying communication mechanism with the SCP.
The SCPI and the associated MHU drivers are moved into a `drivers`
folder in CSS. The new SCP communication abstraction layer is added
in the `drivers/scp` folder. The existing CSS power management
uses the new APIs to reflect this abstraction.
Change-Id: I7d775129fc0558e9703c2724523fb8f0a916838c
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
diff --git a/plat/arm/css/drivers/scpi/css_scpi.h b/plat/arm/css/drivers/scpi/css_scpi.h
new file mode 100644
index 0000000..d1e7cba
--- /dev/null
+++ b/plat/arm/css/drivers/scpi/css_scpi.h
@@ -0,0 +1,134 @@
+/*
+ * Copyright (c) 2014-2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __CSS_SCPI_H__
+#define __CSS_SCPI_H__
+
+#include <stddef.h>
+#include <stdint.h>
+
+/*
+ * An SCPI command consists of a header and a payload.
+ * The following structure describes the header. It is 64-bit long.
+ */
+typedef struct {
+ /* Command ID */
+ uint32_t id : 7;
+ /* Set ID. Identifies whether this is a standard or extended command. */
+ uint32_t set : 1;
+ /* Sender ID to match a reply. The value is sender specific. */
+ uint32_t sender : 8;
+ /* Size of the payload in bytes (0 - 511) */
+ uint32_t size : 9;
+ uint32_t reserved : 7;
+ /*
+ * Status indicating the success of a command.
+ * See the enum below.
+ */
+ uint32_t status;
+} scpi_cmd_t;
+
+typedef enum {
+ SCPI_SET_NORMAL = 0, /* Normal SCPI commands */
+ SCPI_SET_EXTENDED /* Extended SCPI commands */
+} scpi_set_t;
+
+enum {
+ SCP_OK = 0, /* Success */
+ SCP_E_PARAM, /* Invalid parameter(s) */
+ SCP_E_ALIGN, /* Invalid alignment */
+ SCP_E_SIZE, /* Invalid size */
+ SCP_E_HANDLER, /* Invalid handler or callback */
+ SCP_E_ACCESS, /* Invalid access or permission denied */
+ SCP_E_RANGE, /* Value out of range */
+ SCP_E_TIMEOUT, /* Time out has ocurred */
+ SCP_E_NOMEM, /* Invalid memory area or pointer */
+ SCP_E_PWRSTATE, /* Invalid power state */
+ SCP_E_SUPPORT, /* Feature not supported or disabled */
+ SCPI_E_DEVICE, /* Device error */
+ SCPI_E_BUSY, /* Device is busy */
+};
+
+typedef uint32_t scpi_status_t;
+
+typedef enum {
+ SCPI_CMD_SCP_READY = 0x01,
+ SCPI_CMD_SET_CSS_POWER_STATE = 0x03,
+ SCPI_CMD_GET_CSS_POWER_STATE = 0x04,
+ SCPI_CMD_SYS_POWER_STATE = 0x05
+} scpi_command_t;
+
+/*
+ * Macros to parse SCP response to GET_CSS_POWER_STATE command
+ *
+ * [3:0] : cluster ID
+ * [7:4] : cluster state: 0 = on; 3 = off; rest are reserved
+ * [15:8]: on/off state for individual CPUs in the cluster
+ *
+ * Payload is in little-endian
+ */
+#define CLUSTER_ID(_resp) ((_resp) & 0xf)
+#define CLUSTER_POWER_STATE(_resp) (((_resp) >> 4) & 0xf)
+
+/* Result is a bit mask of CPU on/off states in the cluster */
+#define CPU_POWER_STATE(_resp) (((_resp) >> 8) & 0xff)
+
+/*
+ * For GET_CSS_POWER_STATE, SCP returns the power states of every cluster. The
+ * size of response depends on the number of clusters in the system. The
+ * SCP-to-AP payload contains 2 bytes per cluster. Make sure the response is
+ * large enough to contain power states of a given cluster
+ */
+#define CHECK_RESPONSE(_resp, _clus) \
+ (_resp.size >= (((_clus) + 1) * 2))
+
+typedef enum {
+ scpi_power_on = 0,
+ scpi_power_retention = 1,
+ scpi_power_off = 3,
+} scpi_power_state_t;
+
+typedef enum {
+ scpi_system_shutdown = 0,
+ scpi_system_reboot = 1,
+ scpi_system_reset = 2
+} scpi_system_state_t;
+
+extern int scpi_wait_ready(void);
+extern void scpi_set_css_power_state(unsigned int mpidr,
+ scpi_power_state_t cpu_state,
+ scpi_power_state_t cluster_state,
+ scpi_power_state_t css_state);
+int scpi_get_css_power_state(unsigned int mpidr, unsigned int *cpu_state_p,
+ unsigned int *cluster_state_p);
+uint32_t scpi_sys_power_state(scpi_system_state_t system_state);
+
+
+#endif /* __CSS_SCPI_H__ */