1/* 2 * Copyright (C) 2016 Broadcom 3 * 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. 7 * 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. 12 */ 13#include <linux/serial_reg.h> 14 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) 19 20/* Product id can be read from here */ 21#define SUN_TOP_CTRL_BASE REG_PHYS_ADDR(0x404000) 22 23#define UARTA_3390 REG_PHYS_ADDR(0x40a900) 24#define UARTA_7250 REG_PHYS_ADDR(0x40b400) 25#define UARTA_7260 REG_PHYS_ADDR(0x40c000) 26#define UARTA_7268 UARTA_7260 27#define UARTA_7271 UARTA_7268 28#define UARTA_7364 REG_PHYS_ADDR(0x40b000) 29#define UARTA_7366 UARTA_7364 30#define UARTA_74371 REG_PHYS_ADDR(0x406b00) 31#define UARTA_7439 REG_PHYS_ADDR(0x40a900) 32#define UARTA_7445 REG_PHYS_ADDR(0x40ab00) 33 34#define UART_SHIFT 2 35 36#define checkuart(rp, rv, family_id, family) \ 37 /* Load family id */ \ 38 ldr rp, =family_id ; \ 39 /* Compare SUN_TOP_CTRL value against it */ \ 40 cmp rp, rv ; \ 41 /* Passed test, load address */ \ 42 ldreq rp, =UARTA_##family ; \ 43 /* Jump to save UART address */ \ 44 beq 91f 45 46 .macro addruart, rp, rv, tmp 47 adr \rp, 99f @ actual addr of 99f 48 ldr \rv, [\rp] @ linked addr is stored there 49 sub \rv, \rv, \rp @ offset between the two 50 ldr \rp, [\rp, #4] @ linked brcmstb_uart_config 51 sub \tmp, \rp, \rv @ actual brcmstb_uart_config 52 ldr \rp, [\tmp] @ Load brcmstb_uart_config 53 cmp \rp, #1 @ needs initialization? 54 bne 100f @ no; go load the addresses 55 mov \rv, #0 @ yes; record init is done 56 str \rv, [\tmp] 57 58 /* Check SUN_TOP_CTRL base */ 59 ldr \rp, =SUN_TOP_CTRL_BASE @ load SUN_TOP_CTRL PA 60 ldr \rv, [\rp, #0] @ get register contents 61ARM_BE8( rev \rv, \rv ) 62 and \rv, \rv, #0xffffff00 @ strip revision bits [7:0] 63 64 /* Chip specific detection starts here */ 6520: checkuart(\rp, \rv, 0x33900000, 3390) 6621: checkuart(\rp, \rv, 0x72500000, 7250) 6722: checkuart(\rp, \rv, 0x72600000, 7260) 6823: checkuart(\rp, \rv, 0x72680000, 7268) 6924: checkuart(\rp, \rv, 0x72710000, 7271) 7025: checkuart(\rp, \rv, 0x73640000, 7364) 7126: checkuart(\rp, \rv, 0x73660000, 7366) 7227: checkuart(\rp, \rv, 0x07437100, 74371) 7328: checkuart(\rp, \rv, 0x74390000, 7439) 7429: checkuart(\rp, \rv, 0x74450000, 7445) 75 76 /* No valid UART found */ 7790: mov \rp, #0 78 /* fall through */ 79 80 /* Record whichever UART we chose */ 8191: str \rp, [\tmp, #4] @ Store in brcmstb_uart_phys 82 cmp \rp, #0 @ Valid UART address? 83 bne 92f @ Yes, go process it 84 str \rp, [\tmp, #8] @ Store 0 in brcmstb_uart_virt 85 b 100f @ Done 8692: and \rv, \rp, #0xffffff @ offset within 16MB section 87 add \rv, \rv, #REG_VIRT_BASE 88 str \rv, [\tmp, #8] @ Store in brcmstb_uart_virt 89 b 100f 90 91 .align 9299: .word . 93 .word brcmstb_uart_config 94 .ltorg 95 96 /* Load previously selected UART address */ 97100: ldr \rp, [\tmp, #4] @ Load brcmstb_uart_phys 98 ldr \rv, [\tmp, #8] @ Load brcmstb_uart_virt 99 .endm 100 101 .macro store, rd, rx:vararg 102ARM_BE8( rev \rd, \rd ) 103 str \rd, \rx 104 .endm 105 106 .macro load, rd, rx:vararg 107 ldr \rd, \rx 108ARM_BE8( rev \rd, \rd ) 109 .endm 110 111 .macro senduart,rd,rx 112 store \rd, [\rx, #UART_TX << UART_SHIFT] 113 .endm 114 115 .macro busyuart,rd,rx 1161002: load \rd, [\rx, #UART_LSR << UART_SHIFT] 117 and \rd, \rd, #UART_LSR_TEMT | UART_LSR_THRE 118 teq \rd, #UART_LSR_TEMT | UART_LSR_THRE 119 bne 1002b 120 .endm 121 122 .macro waituart,rd,rx 123 .endm 124 125/* 126 * Storage for the state maintained by the macros above. 127 * 128 * In the kernel proper, this data is located in arch/arm/mach-bcm/brcmstb.c. 129 * That's because this header is included from multiple files, and we only 130 * want a single copy of the data. In particular, the UART probing code above 131 * assumes it's running using physical addresses. This is true when this file 132 * is included from head.o, but not when included from debug.o. So we need 133 * to share the probe results between the two copies, rather than having 134 * to re-run the probing again later. 135 * 136 * In the decompressor, we put the symbol/storage right here, since common.c 137 * isn't included in the decompressor build. This symbol gets put in .text 138 * even though it's really data, since .data is discarded from the 139 * decompressor. Luckily, .text is writeable in the decompressor, unless 140 * CONFIG_ZBOOT_ROM. That dependency is handled in arch/arm/Kconfig.debug. 141 */ 142#if defined(ZIMAGE) 143brcmstb_uart_config: 144 /* Debug UART initialization required */ 145 .word 1 146 /* Debug UART physical address */ 147 .word 0 148 /* Debug UART virtual address */ 149 .word 0 150#endif 151