2 * Copyright (C) 2016 Broadcom
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation version 2.
8 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9 * kind, whether express or implied; without even the implied warranty
10 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 #include <linux/serial_reg.h>
15 /* Physical register offset and virtual register offset */
16 #define REG_PHYS_BASE 0xf0000000
17 #define REG_VIRT_BASE 0xfc000000
18 #define REG_PHYS_ADDR(x) ((x) + REG_PHYS_BASE)
20 /* Product id can be read from here */
21 #define SUN_TOP_CTRL_BASE REG_PHYS_ADDR(0x404000)
23 #define UARTA_3390 REG_PHYS_ADDR(0x40a900)
24 #define UARTA_7250 REG_PHYS_ADDR(0x40b400)
25 #define UARTA_7268 REG_PHYS_ADDR(0x40c000)
26 #define UARTA_7271 UARTA_7268
27 #define UARTA_7364 REG_PHYS_ADDR(0x40b000)
28 #define UARTA_7366 UARTA_7364
29 #define UARTA_74371 REG_PHYS_ADDR(0x406b00)
30 #define UARTA_7439 REG_PHYS_ADDR(0x40a900)
31 #define UARTA_7445 REG_PHYS_ADDR(0x40ab00)
35 #define checkuart(rp, rv, family_id, family) \
36 /* Load family id */ \
37 ldr rp, =family_id ; \
38 /* Compare SUN_TOP_CTRL value against it */ \
40 /* Passed test, load address */ \
41 ldreq rp, =UARTA_##family ; \
42 /* Jump to save UART address */ \
45 .macro addruart, rp, rv, tmp
46 adr \rp, 99f @ actual addr of 99f
47 ldr \rv, [\rp] @ linked addr is stored there
48 sub \rv, \rv, \rp @ offset between the two
49 ldr \rp, [\rp, #4] @ linked brcmstb_uart_config
50 sub \tmp, \rp, \rv @ actual brcmstb_uart_config
51 ldr \rp, [\tmp] @ Load brcmstb_uart_config
52 cmp \rp, #1 @ needs initialization?
53 bne 100f @ no; go load the addresses
54 mov \rv, #0 @ yes; record init is done
57 /* Check SUN_TOP_CTRL base */
58 ldr \rp, =SUN_TOP_CTRL_BASE @ load SUN_TOP_CTRL PA
59 ldr \rv, [\rp, #0] @ get register contents
60 and \rv, \rv, #0xffffff00 @ strip revision bits [7:0]
62 /* Chip specific detection starts here */
63 20: checkuart(\rp, \rv, 0x33900000, 3390)
64 21: checkuart(\rp, \rv, 0x72500000, 7250)
65 22: checkuart(\rp, \rv, 0x72680000, 7268)
66 23: checkuart(\rp, \rv, 0x72710000, 7271)
67 24: checkuart(\rp, \rv, 0x73640000, 7364)
68 25: checkuart(\rp, \rv, 0x73660000, 7366)
69 26: checkuart(\rp, \rv, 0x07437100, 74371)
70 27: checkuart(\rp, \rv, 0x74390000, 7439)
71 28: checkuart(\rp, \rv, 0x74450000, 7445)
73 /* No valid UART found */
77 /* Record whichever UART we chose */
78 91: str \rp, [\tmp, #4] @ Store in brcmstb_uart_phys
79 cmp \rp, #0 @ Valid UART address?
80 bne 92f @ Yes, go process it
81 str \rp, [\tmp, #8] @ Store 0 in brcmstb_uart_virt
83 92: and \rv, \rp, #0xffffff @ offset within 16MB section
84 add \rv, \rv, #REG_VIRT_BASE
85 str \rv, [\tmp, #8] @ Store in brcmstb_uart_virt
90 .word brcmstb_uart_config
93 /* Load previously selected UART address */
94 100: ldr \rp, [\tmp, #4] @ Load brcmstb_uart_phys
95 ldr \rv, [\tmp, #8] @ Load brcmstb_uart_virt
98 .macro store, rd, rx:vararg
102 .macro load, rd, rx:vararg
106 .macro senduart,rd,rx
107 store \rd, [\rx, #UART_TX << UART_SHIFT]
110 .macro busyuart,rd,rx
111 1002: load \rd, [\rx, #UART_LSR << UART_SHIFT]
112 and \rd, \rd, #UART_LSR_TEMT | UART_LSR_THRE
113 teq \rd, #UART_LSR_TEMT | UART_LSR_THRE
117 .macro waituart,rd,rx
121 * Storage for the state maintained by the macros above.
123 * In the kernel proper, this data is located in arch/arm/mach-bcm/brcmstb.c.
124 * That's because this header is included from multiple files, and we only
125 * want a single copy of the data. In particular, the UART probing code above
126 * assumes it's running using physical addresses. This is true when this file
127 * is included from head.o, but not when included from debug.o. So we need
128 * to share the probe results between the two copies, rather than having
129 * to re-run the probing again later.
131 * In the decompressor, we put the symbol/storage right here, since common.c
132 * isn't included in the decompressor build. This symbol gets put in .text
133 * even though it's really data, since .data is discarded from the
134 * decompressor. Luckily, .text is writeable in the decompressor, unless
135 * CONFIG_ZBOOT_ROM. That dependency is handled in arch/arm/Kconfig.debug.
139 /* Debug UART initialization required */
141 /* Debug UART physical address */
143 /* Debug UART virtual address */