3 * Andrew May, Viasat Inc, amay@viasat.com
5 * SPDX-License-Identifier: GPL-2.0+
9 * M41T11 Serial Access Timekeeper(R) SRAM
10 * can you believe a trademark on that?
21 I Don't have an example config file but this
22 is what should be done.
24 #define CONFIG_RTC_M41T11 1
25 #define CONFIG_SYS_I2C_RTC_ADDR 0x68
27 #define CONFIG_SYS_M41T11_EXT_CENTURY_DATA
29 #define CONFIG_SYS_M41T11_BASE_YEAR 2000
33 #if defined(CONFIG_SYS_I2C_RTC_ADDR) && defined(CONFIG_CMD_DATE)
35 /* ------------------------------------------------------------------------- */
37 these are simple defines for the chip local to here so they aren't too
39 DAY/DATE aren't nice but that is how they are on the data sheet
41 #define RTC_SEC_ADDR 0x0
42 #define RTC_MIN_ADDR 0x1
43 #define RTC_HOUR_ADDR 0x2
44 #define RTC_DAY_ADDR 0x3
45 #define RTC_DATE_ADDR 0x4
46 #define RTC_MONTH_ADDR 0x5
47 #define RTC_YEARS_ADDR 0x6
51 #define RTC_CONTROL_ADDR 0x7
54 #ifndef CONFIG_SYS_M41T11_EXT_CENTURY_DATA
56 #define REG_CNT (RTC_REG_CNT+1)
59 you only get 00-99 for the year we will asume you
60 want from the year 2000 if you don't set the config
62 #ifndef CONFIG_SYS_M41T11_BASE_YEAR
63 #define CONFIG_SYS_M41T11_BASE_YEAR 2000
67 /* we will store extra year info in byte 9*/
68 #define M41T11_YEAR_DATA 0x8
69 #define M41T11_YEAR_SIZE 1
70 #define REG_CNT (RTC_REG_CNT+1+M41T11_YEAR_SIZE)
73 #define M41T11_STORAGE_SZ (64-REG_CNT)
75 int rtc_get (struct rtc_time
*tmp
)
78 uchar data
[RTC_REG_CNT
];
80 i2c_read(CONFIG_SYS_I2C_RTC_ADDR
, RTC_SEC_ADDR
, 1, data
, RTC_REG_CNT
);
82 if( data
[RTC_SEC_ADDR
] & 0x80 ){
83 printf( "m41t11 RTC Clock stopped!!!\n" );
86 tmp
->tm_sec
= bcd2bin (data
[RTC_SEC_ADDR
] & 0x7F);
87 tmp
->tm_min
= bcd2bin (data
[RTC_MIN_ADDR
] & 0x7F);
88 tmp
->tm_hour
= bcd2bin (data
[RTC_HOUR_ADDR
] & 0x3F);
89 tmp
->tm_mday
= bcd2bin (data
[RTC_DATE_ADDR
] & 0x3F);
90 tmp
->tm_mon
= bcd2bin (data
[RTC_MONTH_ADDR
]& 0x1F);
91 #ifndef CONFIG_SYS_M41T11_EXT_CENTURY_DATA
92 tmp
->tm_year
= CONFIG_SYS_M41T11_BASE_YEAR
93 + bcd2bin(data
[RTC_YEARS_ADDR
])
94 + ((data
[RTC_HOUR_ADDR
]&0x40) ? 100 : 0);
98 i2c_read(CONFIG_SYS_I2C_RTC_ADDR
, M41T11_YEAR_DATA
, 1, ¢
, M41T11_YEAR_SIZE
);
99 if( !(data
[RTC_HOUR_ADDR
] & 0x80) ){
100 printf( "m41t11 RTC: cann't keep track of years without CEB set\n" );
103 if( (cent
& 0x1) != ((data
[RTC_HOUR_ADDR
]&0x40)>>7) ){
104 /*century flip store off new year*/
106 i2c_write(CONFIG_SYS_I2C_RTC_ADDR
, M41T11_YEAR_DATA
, 1, ¢
, M41T11_YEAR_SIZE
);
108 tmp
->tm_year
=((int)cent
*100)+bcd2bin(data
[RTC_YEARS_ADDR
]);
111 tmp
->tm_wday
= bcd2bin (data
[RTC_DAY_ADDR
] & 0x07);
115 debug ( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
116 tmp
->tm_year
, tmp
->tm_mon
, tmp
->tm_mday
, tmp
->tm_wday
,
117 tmp
->tm_hour
, tmp
->tm_min
, tmp
->tm_sec
);
122 int rtc_set (struct rtc_time
*tmp
)
124 uchar data
[RTC_REG_CNT
];
126 debug ( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
127 tmp
->tm_year
, tmp
->tm_mon
, tmp
->tm_mday
, tmp
->tm_wday
,
128 tmp
->tm_hour
, tmp
->tm_min
, tmp
->tm_sec
);
130 data
[RTC_SEC_ADDR
] = bin2bcd(tmp
->tm_sec
) & 0x7F;/*just in case*/
131 data
[RTC_MIN_ADDR
] = bin2bcd(tmp
->tm_min
);
132 data
[RTC_HOUR_ADDR
] = bin2bcd(tmp
->tm_hour
) & 0x3F;/*handle cent stuff later*/
133 data
[RTC_DATE_ADDR
] = bin2bcd(tmp
->tm_mday
) & 0x3F;
134 data
[RTC_MONTH_ADDR
] = bin2bcd(tmp
->tm_mon
);
135 data
[RTC_DAY_ADDR
] = bin2bcd(tmp
->tm_wday
) & 0x07;
137 data
[RTC_HOUR_ADDR
] |= 0x80;/*we will always use CEB*/
139 data
[RTC_YEARS_ADDR
] = bin2bcd(tmp
->tm_year
%100);/*same thing either way*/
140 #ifndef CONFIG_SYS_M41T11_EXT_CENTURY_DATA
141 if( ((tmp
->tm_year
- CONFIG_SYS_M41T11_BASE_YEAR
) > 200) ||
142 (tmp
->tm_year
< CONFIG_SYS_M41T11_BASE_YEAR
) ){
143 printf( "m41t11 RTC setting year out of range!!need recompile\n" );
145 data
[RTC_HOUR_ADDR
] |= (tmp
->tm_year
- CONFIG_SYS_M41T11_BASE_YEAR
) > 100 ? 0x40 : 0;
149 cent
= tmp
->tm_year
? tmp
->tm_year
/ 100 : 0;
150 data
[RTC_HOUR_ADDR
] |= (cent
& 0x1) ? 0x40 : 0;
151 i2c_write(CONFIG_SYS_I2C_RTC_ADDR
, M41T11_YEAR_DATA
, 1, ¢
, M41T11_YEAR_SIZE
);
154 i2c_write(CONFIG_SYS_I2C_RTC_ADDR
, RTC_SEC_ADDR
, 1, data
, RTC_REG_CNT
);
159 void rtc_reset (void)
162 /* clear all control & status registers */
163 i2c_read(CONFIG_SYS_I2C_RTC_ADDR
, RTC_SEC_ADDR
, 1, &val
, 1);
164 val
= val
& 0x7F;/*make sure we are running*/
165 i2c_write(CONFIG_SYS_I2C_RTC_ADDR
, RTC_SEC_ADDR
, 1, &val
, RTC_REG_CNT
);
167 i2c_read(CONFIG_SYS_I2C_RTC_ADDR
, RTC_CONTROL_ADDR
, 1, &val
, 1);
168 val
= val
& 0x3F;/*turn off freq test keep calibration*/
169 i2c_write(CONFIG_SYS_I2C_RTC_ADDR
, RTC_CONTROL_ADDR
, 1, &val
, 1);