xref: /linux/arch/arm/include/debug/brcmstb.S (revision 4b660dbd9ee2059850fd30e0df420ca7a38a1856)
1/* SPDX-License-Identifier: GPL-2.0-only */
2/* Copyright (C) 2016 Broadcom */
3#include <linux/serial_reg.h>
4#include <asm/cputype.h>
5
6/* Physical register offset and virtual register offset */
7#define REG_PHYS_BASE		0xf0000000
8#define REG_PHYS_BASE_V7	0x08000000
9#define REG_VIRT_BASE		0xfc000000
10#define REG_PHYS_ADDR(x)	((x) + REG_PHYS_BASE)
11#define REG_PHYS_ADDR_V7(x)	((x) + REG_PHYS_BASE_V7)
12
13/* Product id can be read from here */
14#define SUN_TOP_CTRL_BASE	REG_PHYS_ADDR(0x404000)
15#define SUN_TOP_CTRL_BASE_V7	REG_PHYS_ADDR_V7(0x404000)
16
17#define UARTA_3390		REG_PHYS_ADDR(0x40a900)
18#define UARTA_72116		UARTA_7255
19#define UARTA_7250		REG_PHYS_ADDR(0x40b400)
20#define UARTA_7255		REG_PHYS_ADDR(0x40c000)
21#define UARTA_7260		UARTA_7255
22#define UARTA_7268		UARTA_7255
23#define UARTA_7271		UARTA_7268
24#define UARTA_7278		REG_PHYS_ADDR_V7(0x40c000)
25#define UARTA_7216		UARTA_7278
26#define UARTA_72164		UARTA_7278
27#define UARTA_72165		UARTA_7278
28#define UARTA_7364		REG_PHYS_ADDR(0x40b000)
29#define UARTA_7366		UARTA_7364
30#define UARTA_74165		UARTA_7278
31#define UARTA_74371		REG_PHYS_ADDR(0x406b00)
32#define UARTA_7439		REG_PHYS_ADDR(0x40a900)
33#define UARTA_7445		REG_PHYS_ADDR(0x40ab00)
34
35#define UART_SHIFT		2
36
37#define checkuart(rp, rv, family_id, family) \
38		/* Load family id */ \
39		ldr	rp, =family_id ; \
40		/* Compare SUN_TOP_CTRL value against it */ \
41		cmp	rp, rv ; \
42		/* Passed test, load address */ \
43		ldreq	rp, =UARTA_##family ; \
44		/* Jump to save UART address */ \
45		beq	91f
46
47		.macro  addruart, rp, rv, tmp
48		adr	\rp, 99f		@ actual addr of 99f
49		ldr	\rv, [\rp]		@ linked addr is stored there
50		sub	\rv, \rv, \rp		@ offset between the two
51		ldr	\rp, [\rp, #4]		@ linked brcmstb_uart_config
52		sub	\tmp, \rp, \rv		@ actual brcmstb_uart_config
53		ldr	\rp, [\tmp]		@ Load brcmstb_uart_config
54		cmp	\rp, #1			@ needs initialization?
55		bne	100f			@ no; go load the addresses
56		mov	\rv, #0			@ yes; record init is done
57		str	\rv, [\tmp]
58
59		/* Check for V7 memory map if B53 */
60		mrc	p15, 0, \rv, c0, c0, 0	@ get Main ID register
61		ldr	\rp, =ARM_CPU_PART_MASK
62		and	\rv, \rv, \rp
63		ldr	\rp, =ARM_CPU_PART_BRAHMA_B53	@ check for B53 CPU
64		cmp	\rv, \rp
65		bne	10f
66
67		/* if PERIPHBASE doesn't overlap REG_PHYS_BASE use V7 map */
68		mrc	p15, 1, \rv, c15, c3, 0	@ get PERIPHBASE from CBAR
69		ands	\rv, \rv, #REG_PHYS_BASE
70		ldreq	\rp, =SUN_TOP_CTRL_BASE_V7
71
72		/* Check SUN_TOP_CTRL base */
7310:		ldrne	\rp, =SUN_TOP_CTRL_BASE	@ load SUN_TOP_CTRL PA
74		ldr	\rv, [\rp, #0]		@ get register contents
75ARM_BE8(	rev	\rv, \rv )
76		and	\rv, \rv, #0xffffff00	@ strip revision bits [7:0]
77
78		/* Chip specific detection starts here */
7920:		checkuart(\rp, \rv, 0x33900000, 3390)
8021:		checkuart(\rp, \rv, 0x07211600, 72116)
8122:		checkuart(\rp, \rv, 0x72160000, 7216)
8223:		checkuart(\rp, \rv, 0x07216400, 72164)
8324:		checkuart(\rp, \rv, 0x07216500, 72165)
8425:		checkuart(\rp, \rv, 0x72500000, 7250)
8526:		checkuart(\rp, \rv, 0x72550000, 7255)
8627:		checkuart(\rp, \rv, 0x72600000, 7260)
8728:		checkuart(\rp, \rv, 0x72680000, 7268)
8829:		checkuart(\rp, \rv, 0x72710000, 7271)
8930:		checkuart(\rp, \rv, 0x72780000, 7278)
9031:		checkuart(\rp, \rv, 0x73640000, 7364)
9132:		checkuart(\rp, \rv, 0x73660000, 7366)
9233:		checkuart(\rp, \rv, 0x07416500, 74165)
9334:		checkuart(\rp, \rv, 0x07437100, 74371)
9435:		checkuart(\rp, \rv, 0x74390000, 7439)
9536:		checkuart(\rp, \rv, 0x74450000, 7445)
96
97		/* No valid UART found */
9890:		mov	\rp, #0
99		/* fall through */
100
101		/* Record whichever UART we chose */
10291:		str	\rp, [\tmp, #4]		@ Store in brcmstb_uart_phys
103		cmp	\rp, #0			@ Valid UART address?
104		bne	92f			@ Yes, go process it
105		str	\rp, [\tmp, #8]		@ Store 0 in brcmstb_uart_virt
106		b	100f			@ Done
10792:		and     \rv, \rp, #0xffffff	@ offset within 16MB section
108		add	\rv, \rv, #REG_VIRT_BASE
109		str	\rv, [\tmp, #8]		@ Store in brcmstb_uart_virt
110		b	100f
111
112		.align
11399:		.word	.
114		.word	brcmstb_uart_config
115		.ltorg
116
117		/* Load previously selected UART address */
118100:		ldr	\rp, [\tmp, #4]		@ Load brcmstb_uart_phys
119		ldr	\rv, [\tmp, #8]		@ Load brcmstb_uart_virt
120		.endm
121
122		.macro	store, rd, rx:vararg
123ARM_BE8(	rev	\rd, \rd )
124		str	\rd, \rx
125		.endm
126
127		.macro	load, rd, rx:vararg
128		ldr	\rd, \rx
129ARM_BE8(	rev	\rd, \rd )
130		.endm
131
132		.macro	senduart,rd,rx
133		store	\rd, [\rx, #UART_TX << UART_SHIFT]
134		.endm
135
136		.macro	busyuart,rd,rx
1371002:		load	\rd, [\rx, #UART_LSR << UART_SHIFT]
138		and	\rd, \rd, #UART_LSR_TEMT | UART_LSR_THRE
139		teq	\rd, #UART_LSR_TEMT | UART_LSR_THRE
140		bne	1002b
141		.endm
142
143		.macro	waituarttxrdy,rd,rx
144		.endm
145
146		.macro	waituartcts,rd,rx
147		.endm
148
149/*
150 * Storage for the state maintained by the macros above.
151 *
152 * In the kernel proper, this data is located in arch/arm/mach-bcm/brcmstb.c.
153 * That's because this header is included from multiple files, and we only
154 * want a single copy of the data. In particular, the UART probing code above
155 * assumes it's running using physical addresses. This is true when this file
156 * is included from head.o, but not when included from debug.o. So we need
157 * to share the probe results between the two copies, rather than having
158 * to re-run the probing again later.
159 *
160 * In the decompressor, we put the symbol/storage right here, since common.c
161 * isn't included in the decompressor build. This symbol gets put in .text
162 * even though it's really data, since .data is discarded from the
163 * decompressor. Luckily, .text is writeable in the decompressor, unless
164 * CONFIG_ZBOOT_ROM. That dependency is handled in arch/arm/Kconfig.debug.
165 */
166#if defined(ZIMAGE)
167brcmstb_uart_config:
168	/* Debug UART initialization required */
169	.word 1
170	/* Debug UART physical address */
171	.word 0
172	/* Debug UART virtual address */
173	.word 0
174#endif
175