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 61 and \rv, \rv, #0xffffff00 @ strip revision bits [7:0] 62 63 /* Chip specific detection starts here */ 6420: checkuart(\rp, \rv, 0x33900000, 3390) 6521: checkuart(\rp, \rv, 0x72500000, 7250) 6622: checkuart(\rp, \rv, 0x72600000, 7260) 6723: checkuart(\rp, \rv, 0x72680000, 7268) 6824: checkuart(\rp, \rv, 0x72710000, 7271) 6925: checkuart(\rp, \rv, 0x73640000, 7364) 7026: checkuart(\rp, \rv, 0x73660000, 7366) 7127: checkuart(\rp, \rv, 0x07437100, 74371) 7228: checkuart(\rp, \rv, 0x74390000, 7439) 7329: checkuart(\rp, \rv, 0x74450000, 7445) 74 75 /* No valid UART found */ 7690: mov \rp, #0 77 /* fall through */ 78 79 /* Record whichever UART we chose */ 8091: str \rp, [\tmp, #4] @ Store in brcmstb_uart_phys 81 cmp \rp, #0 @ Valid UART address? 82 bne 92f @ Yes, go process it 83 str \rp, [\tmp, #8] @ Store 0 in brcmstb_uart_virt 84 b 100f @ Done 8592: and \rv, \rp, #0xffffff @ offset within 16MB section 86 add \rv, \rv, #REG_VIRT_BASE 87 str \rv, [\tmp, #8] @ Store in brcmstb_uart_virt 88 b 100f 89 90 .align 9199: .word . 92 .word brcmstb_uart_config 93 .ltorg 94 95 /* Load previously selected UART address */ 96100: ldr \rp, [\tmp, #4] @ Load brcmstb_uart_phys 97 ldr \rv, [\tmp, #8] @ Load brcmstb_uart_virt 98 .endm 99 100 .macro store, rd, rx:vararg 101 str \rd, \rx 102 .endm 103 104 .macro load, rd, rx:vararg 105 ldr \rd, \rx 106 .endm 107 108 .macro senduart,rd,rx 109 store \rd, [\rx, #UART_TX << UART_SHIFT] 110 .endm 111 112 .macro busyuart,rd,rx 1131002: load \rd, [\rx, #UART_LSR << UART_SHIFT] 114 and \rd, \rd, #UART_LSR_TEMT | UART_LSR_THRE 115 teq \rd, #UART_LSR_TEMT | UART_LSR_THRE 116 bne 1002b 117 .endm 118 119 .macro waituart,rd,rx 120 .endm 121 122/* 123 * Storage for the state maintained by the macros above. 124 * 125 * In the kernel proper, this data is located in arch/arm/mach-bcm/brcmstb.c. 126 * That's because this header is included from multiple files, and we only 127 * want a single copy of the data. In particular, the UART probing code above 128 * assumes it's running using physical addresses. This is true when this file 129 * is included from head.o, but not when included from debug.o. So we need 130 * to share the probe results between the two copies, rather than having 131 * to re-run the probing again later. 132 * 133 * In the decompressor, we put the symbol/storage right here, since common.c 134 * isn't included in the decompressor build. This symbol gets put in .text 135 * even though it's really data, since .data is discarded from the 136 * decompressor. Luckily, .text is writeable in the decompressor, unless 137 * CONFIG_ZBOOT_ROM. That dependency is handled in arch/arm/Kconfig.debug. 138 */ 139#if defined(ZIMAGE) 140brcmstb_uart_config: 141 /* Debug UART initialization required */ 142 .word 1 143 /* Debug UART physical address */ 144 .word 0 145 /* Debug UART virtual address */ 146 .word 0 147#endif 148