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1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Debugging macro include header
4 *
5 * Copyright (C) 1994-1999 Russell King
6 * Moved from linux/arch/arm/kernel/debug.S by Ben Dooks
7*/
8
9#include <linux/serial_reg.h>
10
11/* External port on Zoom2/3 */
12#define ZOOM_UART_BASE 0x10000000
13#define ZOOM_UART_VIRT 0xfa400000
14
15#define OMAP_PORT_SHIFT 2
16#define ZOOM_PORT_SHIFT 1
17
18#define UART_OFFSET(addr) ((addr) & 0x00ffffff)
19
20 .pushsection .data
21 .align 2
22omap_uart_phys: .word 0
23omap_uart_virt: .word 0
24omap_uart_lsr: .word 0
25 .popsection
26
27 .macro addruart, rp, rv, tmp
28
29 /* Use omap_uart_phys/virt if already configured */
3010: adr \rp, 99f @ get effective addr of 99f
31 ldr \rv, [\rp] @ get absolute addr of 99f
32 sub \rv, \rv, \rp @ offset between the two
33 ldr \rp, [\rp, #4] @ abs addr of omap_uart_phys
34 sub \tmp, \rp, \rv @ make it effective
35 ldr \rp, [\tmp, #0] @ omap_uart_phys
36 ldr \rv, [\tmp, #4] @ omap_uart_virt
37 cmp \rp, #0 @ is port configured?
38 cmpne \rv, #0
39 bne 100f @ already configured
40
41 /* Configure the UART offset from the phys/virt base */
42#ifdef CONFIG_DEBUG_ZOOM_UART
43 ldr \rp, =ZOOM_UART_BASE
44 str \rp, [\tmp, #0] @ omap_uart_phys
45 ldr \rp, =ZOOM_UART_VIRT
46 str \rp, [\tmp, #4] @ omap_uart_virt
47 mov \rp, #(UART_LSR << ZOOM_PORT_SHIFT)
48 str \rp, [\tmp, #8] @ omap_uart_lsr
49#endif
50 b 10b
51
52 .align
5399: .word .
54 .word omap_uart_phys
55 .ltorg
56
57100: /* Pass the UART_LSR reg address */
58 ldr \tmp, [\tmp, #8] @ omap_uart_lsr
59 add \rp, \rp, \tmp
60 add \rv, \rv, \tmp
61 .endm
62
63 .macro senduart,rd,rx
64 orr \rd, \rd, \rx, lsl #24 @ preserve LSR reg offset
65 bic \rx, \rx, #0xff @ get base (THR) reg address
66 strb \rd, [\rx] @ send lower byte of rd
67 orr \rx, \rx, \rd, lsr #24 @ restore original rx (LSR)
68 bic \rd, \rd, #(0xff << 24) @ restore original rd
69 .endm
70
71 .macro busyuart,rd,rx
721001: ldrb \rd, [\rx] @ rx contains UART_LSR address
73 and \rd, \rd, #(UART_LSR_TEMT | UART_LSR_THRE)
74 teq \rd, #(UART_LSR_TEMT | UART_LSR_THRE)
75 bne 1001b
76 .endm
77
78 .macro waituartcts,rd,rx
79 .endm
80
81 .macro waituarttxrdy,rd,rx
82 .endm