1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * (C) Copyright 2017 Heiko Stuebner <heiko@sntech.de>
4  * (C) Copyright 2017 Theobroma Systems Design und Consulting GmbH
5  */
6 
7 #ifndef _ASM_ARCH_BOOTROM_H
8 #define _ASM_ARCH_BOOTROM_H
9 
10 #include <linux/types.h>
11 
12 /*
13  * Saved Stack pointer address.
14  * Access might be needed in some special cases.
15  */
16 extern u32 SAVE_SP_ADDR;
17 
18 /**
19  * back_to_bootrom() - return to bootrom (for TPL/SPL), passing a
20  *                     result code
21  *
22  * Transfer control back to the Rockchip BROM, restoring necessary
23  * register context and passing a command/result code to the BROM
24  * to instruct its next actions (e.g. continue boot sequence, enter
25  * download mode, ...).
26  *
27  * This function does not return.
28  *
29  * @brom_cmd: indicates how the bootrom should continue the boot
30  *            sequence (e.g. load the next stage)
31  */
32 enum rockchip_bootrom_cmd {
33 	/*
34 	 * These can not start at 0, as 0 has a special meaning
35 	 * for setjmp().
36 	 */
37 
38 	BROM_BOOT_NEXTSTAGE = 1,  /* continue boot-sequence */
39 	BROM_BOOT_ENTER_DNL,      /* have BROM enter download-mode */
40 };
41 
42 void back_to_bootrom(enum rockchip_bootrom_cmd brom_cmd);
43 
44 /**
45  * Boot-device identifiers as used by the BROM
46  */
47 enum {
48 	BROM_BOOTSOURCE_UNKNOWN = 0,
49 	BROM_BOOTSOURCE_NAND = 1,
50 	BROM_BOOTSOURCE_EMMC = 2,
51 	BROM_BOOTSOURCE_SPINOR = 3,
52 	BROM_BOOTSOURCE_SPINAND = 4,
53 	BROM_BOOTSOURCE_SD = 5,
54 	BROM_BOOTSOURCE_I2C = 8,
55 	BROM_BOOTSOURCE_SPI = 9,
56 	BROM_BOOTSOURCE_USB = 10,
57 	BROM_LAST_BOOTSOURCE = BROM_BOOTSOURCE_USB
58 };
59 
60 extern const char * const boot_devices[BROM_LAST_BOOTSOURCE + 1];
61 
62 /**
63  * Locations of the boot-device identifier in SRAM
64  */
65 #define BROM_BOOTSOURCE_ID_ADDR   (CFG_IRAM_BASE + 0x10)
66 
67 #endif
68