xref: /linux-6.15/arch/arm/include/debug/omap2plus.S (revision 51ef7003)
1/*
2 * Debugging macro include header
3 *
4 *  Copyright (C) 1994-1999 Russell King
5 *  Moved from linux/arch/arm/kernel/debug.S by Ben Dooks
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11*/
12
13#include <linux/serial_reg.h>
14
15/* External port on Zoom2/3 */
16#define ZOOM_UART_BASE		0x10000000
17#define ZOOM_UART_VIRT		0xfa400000
18
19#define OMAP_PORT_SHIFT		2
20#define ZOOM_PORT_SHIFT		1
21
22#define UART_OFFSET(addr)	((addr) & 0x00ffffff)
23
24		.pushsection .data
25omap_uart_phys:	.word	0
26omap_uart_virt:	.word	0
27omap_uart_lsr:	.word	0
28		.popsection
29
30		.macro	addruart, rp, rv, tmp
31
32		/* Use omap_uart_phys/virt if already configured */
3310:		adr	\rp, 99f		@ get effective addr of 99f
34		ldr	\rv, [\rp]		@ get absolute addr of 99f
35		sub	\rv, \rv, \rp		@ offset between the two
36		ldr	\rp, [\rp, #4]		@ abs addr of omap_uart_phys
37		sub	\tmp, \rp, \rv		@ make it effective
38		ldr	\rp, [\tmp, #0]		@ omap_uart_phys
39		ldr	\rv, [\tmp, #4]		@ omap_uart_virt
40		cmp	\rp, #0			@ is port configured?
41		cmpne	\rv, #0
42		bne	100f			@ already configured
43
44		/* Configure the UART offset from the phys/virt base */
45#ifdef CONFIG_DEBUG_ZOOM_UART
46		ldr	\rp, =ZOOM_UART_BASE
47		str	\rp, [\tmp, #0]		@ omap_uart_phys
48		ldr	\rp, =ZOOM_UART_VIRT
49		str	\rp, [\tmp, #4]		@ omap_uart_virt
50		mov	\rp, #(UART_LSR << ZOOM_PORT_SHIFT)
51		str	\rp, [\tmp, #8]		@ omap_uart_lsr
52#endif
53		b	10b
54
55		.align
5699:		.word	.
57		.word	omap_uart_phys
58		.ltorg
59
60100:		/* Pass the UART_LSR reg address */
61		ldr	\tmp, [\tmp, #8]	@ omap_uart_lsr
62		add	\rp, \rp, \tmp
63		add	\rv, \rv, \tmp
64		.endm
65
66		.macro	senduart,rd,rx
67		orr	\rd, \rd, \rx, lsl #24	@ preserve LSR reg offset
68		bic	\rx, \rx, #0xff		@ get base (THR) reg address
69		strb	\rd, [\rx]		@ send lower byte of rd
70		orr	\rx, \rx, \rd, lsr #24	@ restore original rx (LSR)
71		bic	\rd, \rd, #(0xff << 24)	@ restore original rd
72		.endm
73
74		.macro	busyuart,rd,rx
751001:		ldrb	\rd, [\rx]		@ rx contains UART_LSR address
76		and	\rd, \rd, #(UART_LSR_TEMT | UART_LSR_THRE)
77		teq	\rd, #(UART_LSR_TEMT | UART_LSR_THRE)
78		bne	1001b
79		.endm
80
81		.macro	waituart,rd,rx
82		.endm
83