1 // SPDX-License-Identifier: GPL-2.0 <<
2 /* 1 /*
3 * ip22-nvram.c: NVRAM and serial EEPROM handl 2 * ip22-nvram.c: NVRAM and serial EEPROM handling.
4 * 3 *
5 * Copyright (C) 2003 Ladislav Michl (ladis@li 4 * Copyright (C) 2003 Ladislav Michl (ladis@linux-mips.org)
6 */ 5 */
7 #include <linux/export.h> <<
8 6
9 #include <asm/sgi/hpc3.h> 7 #include <asm/sgi/hpc3.h>
10 #include <asm/sgi/ip22.h> 8 #include <asm/sgi/ip22.h>
11 9
12 /* Control opcode for serial eeprom */ 10 /* Control opcode for serial eeprom */
13 #define EEPROM_READ 0xc000 /* serial memo 11 #define EEPROM_READ 0xc000 /* serial memory read */
14 #define EEPROM_WEN 0x9800 /* write enabl 12 #define EEPROM_WEN 0x9800 /* write enable before prog modes */
15 #define EEPROM_WRITE 0xa000 /* serial memo 13 #define EEPROM_WRITE 0xa000 /* serial memory write */
16 #define EEPROM_WRALL 0x8800 /* write all r 14 #define EEPROM_WRALL 0x8800 /* write all registers */
17 #define EEPROM_WDS 0x8000 /* disable all 15 #define EEPROM_WDS 0x8000 /* disable all programming */
18 #define EEPROM_PRREAD 0xc000 /* read protec !! 16 #define EEPROM_PRREAD 0xc000 /* read protect register */
19 #define EEPROM_PREN 0x9800 /* enable prot !! 17 #define EEPROM_PREN 0x9800 /* enable protect register mode */
20 #define EEPROM_PRCLEAR 0xffff /* clear prote !! 18 #define EEPROM_PRCLEAR 0xffff /* clear protect register */
21 #define EEPROM_PRWRITE 0xa000 /* write prote !! 19 #define EEPROM_PRWRITE 0xa000 /* write protect register */
22 #define EEPROM_PRDS 0x8000 /* disable pro !! 20 #define EEPROM_PRDS 0x8000 /* disable protect register, forever */
23 21
24 #define EEPROM_EPROT 0x01 /* Protect reg 22 #define EEPROM_EPROT 0x01 /* Protect register enable */
25 #define EEPROM_CSEL 0x02 /* Chip select 23 #define EEPROM_CSEL 0x02 /* Chip select */
26 #define EEPROM_ECLK 0x04 /* EEPROM cloc 24 #define EEPROM_ECLK 0x04 /* EEPROM clock */
27 #define EEPROM_DATO 0x08 /* Data out */ 25 #define EEPROM_DATO 0x08 /* Data out */
28 #define EEPROM_DATI 0x10 /* Data in */ 26 #define EEPROM_DATI 0x10 /* Data in */
29 27
30 /* We need to use these functions early... */ !! 28 /* We need to use this functions early... */
31 #define delay() ({ !! 29 #define delay() ({ \
32 int x; 30 int x; \
33 for (x=0; x<100000; x++) __asm__ __vol 31 for (x=0; x<100000; x++) __asm__ __volatile__(""); })
34 32
35 #define eeprom_cs_on(ptr) ({ \ 33 #define eeprom_cs_on(ptr) ({ \
36 __raw_writel(__raw_readl(ptr) & ~EEPRO !! 34 *ptr &= ~EEPROM_DATO; \
37 __raw_writel(__raw_readl(ptr) & ~EEPRO !! 35 *ptr &= ~EEPROM_ECLK; \
38 __raw_writel(__raw_readl(ptr) & ~EEPRO !! 36 *ptr &= ~EEPROM_EPROT; \
39 delay(); !! 37 delay(); \
40 __raw_writel(__raw_readl(ptr) | EEPROM !! 38 *ptr |= EEPROM_CSEL; \
41 __raw_writel(__raw_readl(ptr) | EEPROM !! 39 *ptr |= EEPROM_ECLK; })
42 <<
43 40
>> 41
44 #define eeprom_cs_off(ptr) ({ \ 42 #define eeprom_cs_off(ptr) ({ \
45 __raw_writel(__raw_readl(ptr) & ~EEPRO !! 43 *ptr &= ~EEPROM_ECLK; \
46 __raw_writel(__raw_readl(ptr) & ~EEPRO !! 44 *ptr &= ~EEPROM_CSEL; \
47 __raw_writel(__raw_readl(ptr) | EEPROM !! 45 *ptr |= EEPROM_EPROT; \
48 __raw_writel(__raw_readl(ptr) | EEPROM !! 46 *ptr |= EEPROM_ECLK; })
49 47
50 #define BITS_IN_COMMAND 11 !! 48 #define BITS_IN_COMMAND 11
51 /* 49 /*
52 * clock in the nvram command and the register 50 * clock in the nvram command and the register number. For the
53 * national semiconductor nv ram chip the op c 51 * national semiconductor nv ram chip the op code is 3 bits and
54 * the address is 6/8 bits. !! 52 * the address is 6/8 bits.
55 */ 53 */
56 static inline void eeprom_cmd(unsigned int *ct !! 54 static inline void eeprom_cmd(volatile unsigned int *ctrl, unsigned cmd,
>> 55 unsigned reg)
57 { 56 {
58 unsigned short ser_cmd; 57 unsigned short ser_cmd;
59 int i; 58 int i;
60 59
61 ser_cmd = cmd | (reg << (16 - BITS_IN_ 60 ser_cmd = cmd | (reg << (16 - BITS_IN_COMMAND));
62 for (i = 0; i < BITS_IN_COMMAND; i++) 61 for (i = 0; i < BITS_IN_COMMAND; i++) {
63 if (ser_cmd & (1<<15)) /* if 62 if (ser_cmd & (1<<15)) /* if high order bit set */
64 __raw_writel(__raw_rea !! 63 *ctrl |= EEPROM_DATO;
65 else 64 else
66 __raw_writel(__raw_rea !! 65 *ctrl &= ~EEPROM_DATO;
67 __raw_writel(__raw_readl(ctrl) !! 66 *ctrl &= ~EEPROM_ECLK;
68 delay(); !! 67 *ctrl |= EEPROM_ECLK;
69 __raw_writel(__raw_readl(ctrl) <<
70 delay(); <<
71 ser_cmd <<= 1; 68 ser_cmd <<= 1;
72 } 69 }
73 /* see data sheet timing diagram */ !! 70 *ctrl &= ~EEPROM_DATO; /* see data sheet timing diagram */
74 __raw_writel(__raw_readl(ctrl) & ~EEPR <<
75 } 71 }
76 72
77 unsigned short ip22_eeprom_read(unsigned int * !! 73 unsigned short ip22_eeprom_read(volatile unsigned int *ctrl, int reg)
78 { 74 {
79 unsigned short res = 0; 75 unsigned short res = 0;
80 int i; 76 int i;
81 77
82 __raw_writel(__raw_readl(ctrl) & ~EEPR !! 78 *ctrl &= ~EEPROM_EPROT;
83 eeprom_cs_on(ctrl); 79 eeprom_cs_on(ctrl);
84 eeprom_cmd(ctrl, EEPROM_READ, reg); 80 eeprom_cmd(ctrl, EEPROM_READ, reg);
85 81
86 /* clock the data ouf of serial mem */ 82 /* clock the data ouf of serial mem */
87 for (i = 0; i < 16; i++) { 83 for (i = 0; i < 16; i++) {
88 __raw_writel(__raw_readl(ctrl) !! 84 *ctrl &= ~EEPROM_ECLK;
89 delay(); 85 delay();
90 __raw_writel(__raw_readl(ctrl) !! 86 *ctrl |= EEPROM_ECLK;
91 delay(); 87 delay();
92 res <<= 1; 88 res <<= 1;
93 if (__raw_readl(ctrl) & EEPROM !! 89 if (*ctrl & EEPROM_DATI)
94 res |= 1; 90 res |= 1;
95 } 91 }
96 !! 92
97 eeprom_cs_off(ctrl); 93 eeprom_cs_off(ctrl);
98 94
99 return res; 95 return res;
100 } 96 }
101 97
102 EXPORT_SYMBOL(ip22_eeprom_read); <<
103 <<
104 /* 98 /*
105 * Read specified register from main NVRAM 99 * Read specified register from main NVRAM
106 */ 100 */
107 unsigned short ip22_nvram_read(int reg) 101 unsigned short ip22_nvram_read(int reg)
108 { 102 {
109 if (ip22_is_fullhouse()) 103 if (ip22_is_fullhouse())
110 /* IP22 (Indigo2 aka FullHouse 104 /* IP22 (Indigo2 aka FullHouse) stores env variables into
111 * 93CS56 Microwire Bus EEPROM 105 * 93CS56 Microwire Bus EEPROM 2048 Bit (128x16) */
112 return ip22_eeprom_read(&hpc3c 106 return ip22_eeprom_read(&hpc3c0->eeprom, reg);
113 else { 107 else {
114 unsigned short tmp; 108 unsigned short tmp;
115 /* IP24 (Indy aka Guiness) use 109 /* IP24 (Indy aka Guiness) uses DS1386 8K version */
116 reg <<= 1; 110 reg <<= 1;
117 tmp = hpc3c0->bbram[reg++] & 0 111 tmp = hpc3c0->bbram[reg++] & 0xff;
118 return (tmp << 8) | (hpc3c0->b 112 return (tmp << 8) | (hpc3c0->bbram[reg] & 0xff);
119 } !! 113 }
120 } 114 }
121 <<
122 EXPORT_SYMBOL(ip22_nvram_read); <<
123 115
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