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_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) 32 33#define UART_SHIFT 2 34 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 */ \ 39 cmp rp, rv ; \ 40 /* Passed test, load address */ \ 41 ldreq rp, =UARTA_##family ; \ 42 /* Jump to save UART address */ \ 43 beq 91f 44 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 55 str \rv, [\tmp] 56 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] 61 62 /* Chip specific detection starts here */ 6320: checkuart(\rp, \rv, 0x33900000, 3390) 6421: checkuart(\rp, \rv, 0x72500000, 7250) 6522: checkuart(\rp, \rv, 0x72680000, 7268) 6623: checkuart(\rp, \rv, 0x72710000, 7271) 6724: checkuart(\rp, \rv, 0x73640000, 7364) 6825: checkuart(\rp, \rv, 0x73660000, 7366) 6926: checkuart(\rp, \rv, 0x07437100, 74371) 7027: checkuart(\rp, \rv, 0x74390000, 7439) 7128: checkuart(\rp, \rv, 0x74450000, 7445) 72 73 /* No valid UART found */ 7490: mov \rp, #0 75 /* fall through */ 76 77 /* Record whichever UART we chose */ 7891: 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 82 b 100f @ Done 8392: 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 86 b 100f 87 88 .align 8999: .word . 90 .word brcmstb_uart_config 91 .ltorg 92 93 /* Load previously selected UART address */ 94100: ldr \rp, [\tmp, #4] @ Load brcmstb_uart_phys 95 ldr \rv, [\tmp, #8] @ Load brcmstb_uart_virt 96 .endm 97 98 .macro store, rd, rx:vararg 99 str \rd, \rx 100 .endm 101 102 .macro load, rd, rx:vararg 103 ldr \rd, \rx 104 .endm 105 106 .macro senduart,rd,rx 107 store \rd, [\rx, #UART_TX << UART_SHIFT] 108 .endm 109 110 .macro busyuart,rd,rx 1111002: 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 114 bne 1002b 115 .endm 116 117 .macro waituart,rd,rx 118 .endm 119 120/* 121 * Storage for the state maintained by the macros above. 122 * 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. 130 * 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. 136 */ 137#if defined(ZIMAGE) 138brcmstb_uart_config: 139 /* Debug UART initialization required */ 140 .word 1 141 /* Debug UART physical address */ 142 .word 0 143 /* Debug UART virtual address */ 144 .word 0 145#endif 146