1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * (C) Copyright 2015 Miao Yan <yanmiaobest@gmail.com>
4 */
5
6#ifndef __FW_CFG__
7#define __FW_CFG__
8
9#include <linux/list.h>
10
11/*
12 * List of firmware configuration item selectors. The official source of truth
13 * for these is the QEMU source itself; see
14 * https://github.com/qemu/qemu/blob/master/hw/nvram/fw_cfg.c
15 */
16enum {
17	FW_CFG_SIGNATURE	= 0x00,
18	FW_CFG_ID		= 0x01,
19	FW_CFG_UUID		= 0x02,
20	FW_CFG_RAM_SIZE		= 0x03,
21	FW_CFG_NOGRAPHIC	= 0x04,
22	FW_CFG_NB_CPUS		= 0x05,
23	FW_CFG_MACHINE_ID	= 0x06,
24	FW_CFG_KERNEL_ADDR	= 0x07,
25	FW_CFG_KERNEL_SIZE	= 0x08,
26	FW_CFG_KERNEL_CMDLINE   = 0x09,
27	FW_CFG_INITRD_ADDR	= 0x0a,
28	FW_CFG_INITRD_SIZE	= 0x0b,
29	FW_CFG_BOOT_DEVICE	= 0x0c,
30	FW_CFG_NUMA		= 0x0d,
31	FW_CFG_BOOT_MENU	= 0x0e,
32	FW_CFG_MAX_CPUS		= 0x0f,
33	FW_CFG_KERNEL_ENTRY	= 0x10,
34	FW_CFG_KERNEL_DATA	= 0x11,
35	FW_CFG_INITRD_DATA	= 0x12,
36	FW_CFG_CMDLINE_ADDR	= 0x13,
37	FW_CFG_CMDLINE_SIZE	= 0x14,
38	FW_CFG_CMDLINE_DATA	= 0x15,
39	FW_CFG_SETUP_ADDR	= 0x16,
40	FW_CFG_SETUP_SIZE	= 0x17,
41	FW_CFG_SETUP_DATA	= 0x18,
42	FW_CFG_FILE_DIR		= 0x19,
43	FW_CFG_FILE_FIRST	= 0x20,
44	FW_CFG_WRITE_CHANNEL	= 0x4000,
45	FW_CFG_ARCH_LOCAL	= 0x8000,
46	FW_CFG_INVALID		= 0xffff,
47};
48
49enum {
50	BIOS_LINKER_LOADER_COMMAND_ALLOCATE	= 0x1,
51	BIOS_LINKER_LOADER_COMMAND_ADD_POINTER  = 0x2,
52	BIOS_LINKER_LOADER_COMMAND_ADD_CHECKSUM = 0x3,
53};
54
55enum {
56	BIOS_LINKER_LOADER_ALLOC_ZONE_HIGH = 0x1,
57	BIOS_LINKER_LOADER_ALLOC_ZONE_FSEG = 0x2,
58};
59
60#define FW_CFG_FILE_SLOTS	0x10
61#define FW_CFG_MAX_ENTRY	(FW_CFG_FILE_FIRST + FW_CFG_FILE_SLOTS)
62#define FW_CFG_ENTRY_MASK	 ~(FW_CFG_WRITE_CHANNEL | FW_CFG_ARCH_LOCAL)
63
64#define FW_CFG_MAX_FILE_PATH	56
65#define BIOS_LINKER_LOADER_FILESZ FW_CFG_MAX_FILE_PATH
66
67#define QEMU_FW_CFG_SIGNATURE	(('Q' << 24) | ('E' << 16) | ('M' << 8) | 'U')
68
69#define FW_CFG_DMA_ERROR	(1 << 0)
70#define FW_CFG_DMA_READ	(1 << 1)
71#define FW_CFG_DMA_SKIP	(1 << 2)
72#define FW_CFG_DMA_SELECT	(1 << 3)
73
74/* Bit set in FW_CFG_ID response to indicate DMA interface availability. */
75#define FW_CFG_DMA_ENABLED	(1 << 1)
76
77/* Structs read from FW_CFG_FILE_DIR. */
78struct fw_cfg_file {
79	__be32 size;
80	__be16 select;
81	__be16 reserved;
82	char name[FW_CFG_MAX_FILE_PATH];
83};
84
85struct fw_file {
86	struct fw_cfg_file cfg; /* firmware file information */
87	unsigned long addr;     /* firmware file in-memory address */
88	struct list_head list;  /* list node to link to fw_list */
89};
90
91struct fw_cfg_file_iter {
92	struct list_head *entry, *end; /* structures to iterate file list */
93};
94
95struct bios_linker_entry {
96	__le32 command;
97	union {
98		/*
99		 * COMMAND_ALLOCATE - allocate a table from @alloc.file
100		 * subject to @alloc.align alignment (must be power of 2)
101		 * and @alloc.zone (can be HIGH or FSEG) requirements.
102		 *
103		 * Must appear exactly once for each file, and before
104		 * this file is referenced by any other command.
105		 */
106		struct {
107			char file[BIOS_LINKER_LOADER_FILESZ];
108			__le32 align;
109			uint8_t zone;
110		} alloc;
111
112		/*
113		 * COMMAND_ADD_POINTER - patch the table (originating from
114		 * @dest_file) at @pointer.offset, by adding a pointer to the
115		 * table originating from @src_file. 1,2,4 or 8 byte unsigned
116		 * addition is used depending on @pointer.size.
117		 */
118		struct {
119			char dest_file[BIOS_LINKER_LOADER_FILESZ];
120			char src_file[BIOS_LINKER_LOADER_FILESZ];
121			__le32 offset;
122			uint8_t size;
123		} pointer;
124
125		/*
126		 * COMMAND_ADD_CHECKSUM - calculate checksum of the range
127		 * specified by @cksum_start and @cksum_length fields,
128		 * and then add the value at @cksum.offset.
129		 * Checksum simply sums -X for each byte X in the range
130		 * using 8-bit math.
131		 */
132		struct {
133			char file[BIOS_LINKER_LOADER_FILESZ];
134			__le32 offset;
135			__le32 start;
136			__le32 length;
137		} cksum;
138
139		/* padding */
140		char pad[124];
141	};
142} __packed;
143
144/* DMA transfer control data between UCLASS_QFW and QEMU. */
145struct qfw_dma {
146	__be32 control;
147	__be32 length;
148	__be64 address;
149};
150
151/* uclass per-device configuration information */
152struct qfw_dev {
153	struct udevice *dev;		/* Transport device */
154	bool dma_present;		/* DMA interface usable? */
155	struct list_head fw_list;	/* Cached firmware file list */
156};
157
158/* Ops used internally between UCLASS_QFW and its driver implementations. */
159struct dm_qfw_ops {
160	/**
161	 * read_entry_io() - Read a firmware config entry using the regular
162	 * IO interface for the platform (either PIO or MMIO)
163	 *
164	 * Supply %FW_CFG_INVALID as the entry to continue a previous read.  In
165	 * this case, no selector will be issued before reading.
166	 *
167	 * @dev: Device to use
168	 * @entry: Firmware config entry number (e.g. %FW_CFG_SIGNATURE)
169	 * @size: Number of bytes to read
170	 * @address: Target location for read
171	 */
172	void (*read_entry_io)(struct udevice *dev, u16 entry, u32 size,
173			      void *address);
174
175	/**
176	 * read_entry_dma() - Read a firmware config entry using the DMA
177	 * interface
178	 *
179	 * Supply FW_CFG_INVALID as the entry to continue a previous read.  In
180	 * this case, no selector will be issued before reading.
181	 *
182	 * This method assumes DMA availability has already been confirmed.
183	 *
184	 * @dev: Device to use
185	 * @dma: DMA transfer control struct
186	 */
187	void (*read_entry_dma)(struct udevice *dev, struct qfw_dma *dma);
188};
189
190#define dm_qfw_get_ops(dev) \
191		((struct dm_qfw_ops *)(dev)->driver->ops)
192
193/**
194 * qfw_register() - Called by a qfw driver after successful probe.
195 * @dev: Device registering itself with the uclass.
196 *
197 * Used internally by driver implementations on successful probe.
198 *
199 * Return: 0 on success, negative otherwise.
200 */
201int qfw_register(struct udevice *dev);
202
203struct udevice;
204
205/**
206 * qfw_get_dev() - Get QEMU firmware config device.
207 * @devp: Pointer to be filled with address of the qfw device.
208 *
209 * Gets the active QEMU firmware config device, for use with qfw_read_entry()
210 * and others.
211 *
212 * Return: 0 on success, -ENODEV if the device is not available.
213 */
214int qfw_get_dev(struct udevice **devp);
215
216/**
217 * qfw_read_entry() - Read a QEMU firmware config entry
218 * @dev: QFW device to use.
219 * @entry: Firmware config entry number (e.g. %FW_CFG_SIGNATURE).
220 * @size: Number of bytes to read.
221 * @address: Target location for read.
222 *
223 * Reads a QEMU firmware config entry using @dev.  DMA will be used if the QEMU
224 * machine supports it, otherwise PIO/MMIO.
225 */
226void qfw_read_entry(struct udevice *dev, u16 entry, u32 size, void *address);
227
228/**
229 * qfw_read_firmware_list() - Read and cache the QEMU firmware config file
230 * list.
231 * @dev: QFW device to use.
232 *
233 * Reads the QEMU firmware config file list, caching it against @dev for later
234 * use with qfw_find_file().
235 *
236 * If the list has already been read, does nothing and returns 0 (success).
237 *
238 * Return: 0 on success, -ENOMEM if unable to allocate.
239 */
240int qfw_read_firmware_list(struct udevice *dev);
241
242/**
243 * qfw_find_file() - Find a file by name in the QEMU firmware config file
244 * list.
245 * @dev: QFW device to use.
246 * @name: Name of file to locate (e.g. "etc/table-loader").
247 *
248 * Finds a file by name in the QEMU firmware config file list cached against
249 * @dev.  You must call qfw_read_firmware_list() successfully first for this to
250 * succeed.
251 *
252 * Return: Pointer to &struct fw_file if found, %NULL if not present.
253 */
254struct fw_file *qfw_find_file(struct udevice *dev, const char *name);
255
256/**
257 * qfw_online_cpus() - Get number of CPUs in system from QEMU firmware config.
258 * @dev: QFW device to use.
259 *
260 * Asks QEMU to report how many CPUs it is emulating for the machine.
261 *
262 * Return: Number of CPUs in the system.
263 */
264int qfw_online_cpus(struct udevice *dev);
265
266/**
267 * qfw_file_iter_init() - Start iterating cached firmware file list.
268 * @dev: QFW device to use.
269 * @iter: Iterator to be initialised.
270 *
271 * Starts iterating the cached firmware file list in @dev.  You must call
272 * qfw_read_firmware_list() successfully first, otherwise you will always get
273 * an empty list.
274 *
275 * qfw_file_iter_init() returns the first &struct fw_file, but it may be
276 * invalid if the list is empty.  Check that ``!qfw_file_iter_end(&iter)``
277 * first.
278 *
279 * Return: The first &struct fw_file item in the firmware file list, if any.
280 * Only valid when qfw_file_iter_end() is not true after the call.
281 */
282struct fw_file *qfw_file_iter_init(struct udevice *dev,
283				   struct fw_cfg_file_iter *iter);
284
285/**
286 * qfw_file_iter_next() - Iterate cached firmware file list.
287 * @iter: Iterator to use.
288 *
289 * Continues iterating the cached firmware file list in @dev.  You must call
290 * qfw_file_iter_init() first to initialise it.  Check that
291 * ``!qfw_file_iter_end(&iter)`` before using the return value of this
292 * function.
293 *
294 * Return: The next &struct fw_file item in the firmware file list.  Only valid
295 * when qfw_file_iter_end() is not true after the call.
296 */
297struct fw_file *qfw_file_iter_next(struct fw_cfg_file_iter *iter);
298
299/**
300 * qfw_file_iter_end() - Check if iter is at end of list.
301 * @iter: Iterator to use.
302 *
303 * Checks whether or not the iterator is at its end position.  If so, the
304 * qfw_file_iter_init() or qfw_file_iter_next() call that immediately preceded
305 * returned invalid data.
306 *
307 * Return: True if the iterator is at its end; false otherwise.
308 */
309bool qfw_file_iter_end(struct fw_cfg_file_iter *iter);
310
311/**
312 * qemu_cpu_fixup() - Fix up the CPUs for QEMU.
313 *
314 * Return: 0 on success, -ENODEV if no CPUs, -ENOMEM if out of memory, other <
315 * 0 on on other error.
316 */
317int qemu_cpu_fixup(void);
318
319/*
320 * qemu_fwcfg_setup_kernel() - Prepare the kernel for zboot
321 *
322 * Loads kernel data to 'load_addr', initrd to 'initrd_addr' and kernel command
323 * line using qemu fw_cfg interface
324 *
325 * @load_addr: Load address for kernel
326 * @initrd_addr: Load address for ramdisk
327 * @return 0 if OK, -ENOENT if no kernel
328 */
329int qemu_fwcfg_setup_kernel(struct udevice *qfw_dev, ulong load_addr,
330			    ulong initrd_addr);
331
332#endif
333