xref: /openbmc/u-boot/arch/sandbox/include/asm/state.h (revision da4105df)
1 /*
2  * Copyright (c) 2011-2012 The Chromium OS Authors.
3  * SPDX-License-Identifier:	GPL-2.0+
4  */
5 
6 #ifndef __SANDBOX_STATE_H
7 #define __SANDBOX_STATE_H
8 
9 #include <config.h>
10 #include <stdbool.h>
11 #include <linux/stringify.h>
12 
13 /* How we exited U-Boot */
14 enum exit_type_id {
15 	STATE_EXIT_NORMAL,
16 	STATE_EXIT_COLD_REBOOT,
17 	STATE_EXIT_POWER_OFF,
18 };
19 
20 struct sandbox_spi_info {
21 	const char *spec;
22 	const struct sandbox_spi_emu_ops *ops;
23 };
24 
25 /* The complete state of the test system */
26 struct sandbox_state {
27 	const char *cmd;		/* Command to execute */
28 	bool interactive;		/* Enable cmdline after execute */
29 	const char *fdt_fname;		/* Filename of FDT binary */
30 	enum exit_type_id exit_type;	/* How we exited U-Boot */
31 	const char *parse_err;		/* Error to report from parsing */
32 	int argc;			/* Program arguments */
33 	char **argv;
34 	uint8_t *ram_buf;		/* Emulated RAM buffer */
35 	unsigned int ram_size;		/* Size of RAM buffer */
36 	const char *ram_buf_fname;	/* Filename to use for RAM buffer */
37 	bool write_ram_buf;		/* Write RAM buffer on exit */
38 	const char *state_fname;	/* File containing sandbox state */
39 	void *state_fdt;		/* Holds saved state for sandbox */
40 	bool read_state;		/* Read sandbox state on startup */
41 	bool write_state;		/* Write sandbox state on exit */
42 	bool ignore_missing_state_on_read;	/* No error if state missing */
43 
44 	/* Pointer to information for each SPI bus/cs */
45 	struct sandbox_spi_info spi[CONFIG_SANDBOX_SPI_MAX_BUS]
46 					[CONFIG_SANDBOX_SPI_MAX_CS];
47 };
48 
49 /* Minimum space we guarantee in the state FDT when calling read/write*/
50 #define SANDBOX_STATE_MIN_SPACE		0x1000
51 
52 /**
53  * struct sandbox_state_io - methods to saved/restore sandbox state
54  * @name: Name of of the device tree node, also the name of the variable
55  *	holding this data so it should be an identifier (use underscore
56  *	instead of minus)
57  * @compat: Compatible string for the node containing this state
58  *
59  * @read: Function to read state from FDT
60  *	If data is available, then blob and node will provide access to it. If
61  *	not (blob == NULL and node == -1) this function should set up an empty
62  *	data set for start-of-day.
63  *	@param blob: Pointer to device tree blob, or NULL if no data to read
64  *	@param node: Node offset to read from
65  *	@return 0 if OK, -ve on error
66  *
67  * @write: Function to write state to FDT
68  *	The caller will ensure that there is a node ready for the state. The
69  *	node may already contain the old state, in which case it should be
70  *	overridden. There is guaranteed to be SANDBOX_STATE_MIN_SPACE bytes
71  *	of free space, so error checking is not required for fdt_setprop...()
72  *	calls which add up to less than this much space.
73  *
74  *	For adding larger properties, use state_setprop().
75  *
76  * @param blob: Device tree blob holding state
77  * @param node: Node to write our state into
78  *
79  * Note that it is possible to save data as large blobs or as individual
80  * hierarchical properties. However, unless you intend to keep state files
81  * around for a long time and be able to run an old state file on a new
82  * sandbox, it might not be worth using individual properties for everything.
83  * This is certainly supported, it is just a matter of the effort you wish
84  * to put into the state read/write feature.
85  */
86 struct sandbox_state_io {
87 	const char *name;
88 	const char *compat;
89 	int (*write)(void *blob, int node);
90 	int (*read)(const void *blob, int node);
91 };
92 
93 /**
94  * SANDBOX_STATE_IO - Declare sandbox state to read/write
95  *
96  * Sandbox permits saving state from one run and restoring it in another. This
97  * allows the test system to retain state between runs and thus better
98  * emulate a real system. Examples of state that might be useful to save are
99  * the emulated GPIOs pin settings, flash memory contents and TPM private
100  * data. U-Boot memory contents is dealth with separately since it is large
101  * and it is not normally useful to save it (since a normal system does not
102  * preserve DRAM between runs). See the '-m' option for this.
103  *
104  * See struct sandbox_state_io above for member documentation.
105  */
106 #define SANDBOX_STATE_IO(_name, _compat, _read, _write) \
107 	ll_entry_declare(struct sandbox_state_io, _name, state_io) = { \
108 		.name = __stringify(_name), \
109 		.read = _read, \
110 		.write = _write, \
111 		.compat = _compat, \
112 	}
113 
114 /**
115  * Record the exit type to be reported by the test program.
116  *
117  * @param exit_type	Exit type to record
118  */
119 void state_record_exit(enum exit_type_id exit_type);
120 
121 /**
122  * Gets a pointer to the current state.
123  *
124  * @return pointer to state
125  */
126 struct sandbox_state *state_get_current(void);
127 
128 /**
129  * Read the sandbox state from the supplied device tree file
130  *
131  * This calls all registered state handlers to read in the sandbox state
132  * from a previous test run.
133  *
134  * @param state		Sandbox state to update
135  * @param fname		Filename of device tree file to read from
136  * @return 0 if OK, -ve on error
137  */
138 int sandbox_read_state(struct sandbox_state *state, const char *fname);
139 
140 /**
141  * Write the sandbox state to the supplied device tree file
142  *
143  * This calls all registered state handlers to write out the sandbox state
144  * so that it can be preserved for a future test run.
145  *
146  * If the file exists it is overwritten.
147  *
148  * @param state		Sandbox state to update
149  * @param fname		Filename of device tree file to write to
150  * @return 0 if OK, -ve on error
151  */
152 int sandbox_write_state(struct sandbox_state *state, const char *fname);
153 
154 /**
155  * Add a property to a sandbox state node
156  *
157  * This is equivalent to fdt_setprop except that it automatically enlarges
158  * the device tree if necessary. That means it is safe to write any amount
159  * of data here.
160  *
161  * This function can only be called from within struct sandbox_state_io's
162  * ->write method, i.e. within state I/O drivers.
163  *
164  * @param node		Device tree node to write to
165  * @param prop_name	Property to write
166  * @param data		Data to write into property
167  * @param size		Size of data to write into property
168  */
169 int state_setprop(int node, const char *prop_name, const void *data, int size);
170 
171 /**
172  * Initialize the test system state
173  */
174 int state_init(void);
175 
176 /**
177  * Uninitialize the test system state, writing out state if configured to
178  * do so.
179  *
180  * @return 0 if OK, -ve on error
181  */
182 int state_uninit(void);
183 
184 #endif
185