1 /*
2  * Copyright (c) 2014-2017, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #ifndef CSS_SCPI_H
8 #define CSS_SCPI_H
9 
10 #include <stddef.h>
11 #include <stdint.h>
12 
13 /*
14  * An SCPI command consists of a header and a payload.
15  * The following structure describes the header. It is 64-bit long.
16  */
17 typedef struct {
18 	/* Command ID */
19 	uint32_t id		: 7;
20 	/* Set ID. Identifies whether this is a standard or extended command. */
21 	uint32_t set		: 1;
22 	/* Sender ID to match a reply. The value is sender specific. */
23 	uint32_t sender		: 8;
24 	/* Size of the payload in bytes (0 - 511) */
25 	uint32_t size		: 9;
26 	uint32_t reserved	: 7;
27 	/*
28 	 * Status indicating the success of a command.
29 	 * See the enum below.
30 	 */
31 	uint32_t status;
32 } scpi_cmd_t;
33 
34 typedef enum {
35 	SCPI_SET_NORMAL = 0,	/* Normal SCPI commands */
36 	SCPI_SET_EXTENDED	/* Extended SCPI commands */
37 } scpi_set_t;
38 
39 enum {
40 	SCP_OK = 0,	/* Success */
41 	SCP_E_PARAM,	/* Invalid parameter(s) */
42 	SCP_E_ALIGN,	/* Invalid alignment */
43 	SCP_E_SIZE,	/* Invalid size */
44 	SCP_E_HANDLER,	/* Invalid handler or callback */
45 	SCP_E_ACCESS,	/* Invalid access or permission denied */
46 	SCP_E_RANGE,	/* Value out of range */
47 	SCP_E_TIMEOUT,	/* Time out has ocurred */
48 	SCP_E_NOMEM,	/* Invalid memory area or pointer */
49 	SCP_E_PWRSTATE,	/* Invalid power state */
50 	SCP_E_SUPPORT,	/* Feature not supported or disabled */
51 	SCPI_E_DEVICE,	/* Device error */
52 	SCPI_E_BUSY,	/* Device is busy */
53 };
54 
55 typedef uint32_t scpi_status_t;
56 
57 typedef enum {
58 	SCPI_CMD_SCP_READY = 0x01,
59 	SCPI_CMD_SET_CSS_POWER_STATE = 0x03,
60 	SCPI_CMD_GET_CSS_POWER_STATE = 0x04,
61 	SCPI_CMD_SYS_POWER_STATE = 0x05
62 } scpi_command_t;
63 
64 /*
65  * Macros to parse SCP response to GET_CSS_POWER_STATE command
66  *
67  *   [3:0] : cluster ID
68  *   [7:4] : cluster state: 0 = on; 3 = off; rest are reserved
69  *   [15:8]: on/off state for individual CPUs in the cluster
70  *
71  * Payload is in little-endian
72  */
73 #define CLUSTER_ID(_resp)		((_resp) & 0xf)
74 #define CLUSTER_POWER_STATE(_resp)	(((_resp) >> 4) & 0xf)
75 
76 /* Result is a bit mask of CPU on/off states in the cluster */
77 #define CPU_POWER_STATE(_resp)		(((_resp) >> 8) & 0xff)
78 
79 /*
80  * For GET_CSS_POWER_STATE, SCP returns the power states of every cluster. The
81  * size of response depends on the number of clusters in the system. The
82  * SCP-to-AP payload contains 2 bytes per cluster. Make sure the response is
83  * large enough to contain power states of a given cluster
84  */
85 #define CHECK_RESPONSE(_resp, _clus) \
86 	(_resp.size >= (((_clus) + 1) * 2))
87 
88 typedef enum {
89 	scpi_power_on = 0,
90 	scpi_power_retention = 1,
91 	scpi_power_off = 3,
92 } scpi_power_state_t;
93 
94 typedef enum {
95 	scpi_system_shutdown = 0,
96 	scpi_system_reboot = 1,
97 	scpi_system_reset = 2
98 } scpi_system_state_t;
99 
100 int scpi_wait_ready(void);
101 void scpi_set_css_power_state(unsigned int mpidr,
102 				scpi_power_state_t cpu_state,
103 				scpi_power_state_t cluster_state,
104 				scpi_power_state_t css_state);
105 int scpi_get_css_power_state(unsigned int mpidr, unsigned int *cpu_state_p,
106 		unsigned int *cluster_state_p);
107 uint32_t scpi_sys_power_state(scpi_system_state_t system_state);
108 
109 #endif /* CSS_SCPI_H */
110