Changeset 1620

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Timestamp:
11/18/02 21:42:01 (11 years ago)
Author:
khali
Message:

Update (some things had becoming wrong by the time they had been

written) and include Vaio eeproms

Files:
1 modified

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  • lm-sensors/trunk/doc/chips/eeprom

    r1040 r1620  
    1212                Microchip (www.microchip.com) 
    1313 
    14         Chip    Size (bits)     Address 
    15         24C01    1K             0x50 (shadows at 0x51 - 0x57) 
    16         24C01A   1K             0x50 - 0x57 (Typical device on DIMMs) 
    17         24C02    2K             0x50 - 0x57 
    18         24C04    4K             0x50, 0x52, 0x54, 0x56 
    19                                 (additional data at 0x51, 0x53, 0x55, 0x57) 
    20         24C08    8K             0x50, 0x54 (additional data at 0x51, 0x52, 
    21                                 0x53, 0x55, 0x56, 0x57) 
    22         24C16   16K             0x50 (additional data at 0x51 - 0x57) 
     14        Chip     Size (bits)    Address 
     15        24C01     1K            0x50 (shadows at 0x51 - 0x57) 
     16        24C01A    1K            0x50 - 0x57 (Typical device on DIMMs) 
     17        24C02     2K            0x50 - 0x57 
     18        24C04     4K            0x50, 0x52, 0x54, 0x56 
     19                                (additional data at 0x51, 0x53, 0x55, 0x57) 
     20        24C08     8K            0x50, 0x54 (additional data at 0x51, 0x52, 
     21                                0x53, 0x55, 0x56, 0x57) 
     22        24C16    16K            0x50 (additional data at 0x51 - 0x57) 
     23        Sony      2K            0x57 
    2324 
    2425 
     
    5051----------- 
    5152 
    52 This is a simple EEPROM module meant to enable reading the first 128 bytes 
    53 of an EEPROM (on a SDRAM DIMM). However, it will access serial EEPROMs 
    54 on any I2C adapter. This module will probably need to be 
     53This is a simple EEPROM module meant to enable reading the first 256 bytes 
     54of an EEPROM (on a SDRAM DIMM for example). However, it will access serial 
     55EEPROMs on any I2C adapter. This module will probably need to be 
    5556expanded.  A /dev file interface would probably be more effective.  
    5657This module was a programming exercise to get used to the new project 
     
    6970eeprom. 
    7071 
     72Recent Sony Vaio laptops have an EEPROM at 0x57. We couldn't get the 
     73specification, so it is guess work and far from being complete. 
     74 
    7175 
    7276Lacking functionality: 
    7377 
    74 * Read bytes 128-255.  There is no technical restriction for not doing 
    75 this, but making a zillion dataxx-xx files would be a bit rediculous.  
    76 EEPROMs on DIMMs shouldn't use the contents past byte 128, so we are fine.  
    77  
    7878* Full support for larger devices (24C04, 24C08, 24C16). These are 
    7979not typically found on a PC. These devices will appear as separate 
    80 devices at multiple addresses, with every other 128-byte block inaccessable 
    81 because of the missing 128-255 functionality. 
     80devices at multiple addresses. 
    8281 
    83 * Support for really large devices (24C32, 24C64, 24C128, 24C256, 24C5412). 
     82* Support for really large devices (24C32, 24C64, 24C128, 24C256, 24C512). 
    8483These devices require two-byte address fields and are not supported. 
    8584 
    8685* Enable Writing.  Again, no technical reason why not, but making it easy 
    8786to change the contents of the EEPROMs (on DIMMs anyway) also makes it easy 
    88 to disable the DIMMs until the values are restored somehow.  
     87to disable the DIMMs until the values are restored somehow. 
    8988 
    9089 
     
    101100EEPROMs reported are not nessesarily all from DIMMs.  Xeon processors, for 
    102101example, have serial EEPROMs in them connected to the SMBus which will be 
    103 found by the module.  Take care to ignore the output of decode_dimms.pl for 
    104 these EEPROMs. 
     102found by the module.  Take care to ignore the output of decode-dimms.pl for 
     103these EEPROMs.  There is decode-xeon.pl for them.  Same applies to Vaio 
     104EEPROMs, which have decode-vaio.pl. 
    105105 
    106106The driver caches the data from the monitor and only rereads it 
     
    108108 
    109109 
    110 DECODE_DIMMS.PL 
     110Decode-dimms.pl 
    111111--------------- 
    112112 
     
    115115Intel.  When finished, it will decode and report all the values defined in 
    116116the spec.  Much of the information is technical timing and interfacing info 
    117 (probably not all used by the Bios or clocking IC.  
     117(probably not all used by the BIOS or clocking IC). 
    118118 
    119119Note: During testing, we noticed that many DIMMs have trucated SPD records.  
    120120I'm not sure if these conform to an old spec, or if the manufacturers are 
    121 simply just taking short-cuts.  But, many DIMMs have all zeros stored past 
     121simply just taking shortcuts.  But, many DIMMs have all zeros stored past 
    122122byte 21.  I asked an Intel SDRAM tester, Sat Kolli (skolli@smartm.com), 
    123123about this and this is what he had to say: 
     
    130130inconsistencies between spd data from different manufacturers. You could 
    131131read the timing information or the special Intel bytes (126 & 127) but I do 
    132 not know how many program that information.These inconsistencies may be 
     132not know how many program that information. These inconsistencies may be 
    133133minimized if you or your customers stay with some of the better known 
    134 manufacturers."  (Thanks goes to Sat Kolli for his comments and help) 
     134manufacturers."  (Thanks goes to Sat Kolli for his comments and help.) 
    135135 
    136136Use: 
    137137 
    138 After inserting the nessesary modules, run the script! 
     138After inserting the necessary modules, run the script! 
    139139 
    140140Notes: 
     
    142142The script assumes that Perl can be found at /usr/bin/perl.  If different, 
    143143you will need to adjust the first line of the file accordingly, or else 
    144 you will get a strange "decode_dimms.pl: no such file or directory" error. 
     144you will get a strange "decode-dimms.pl: no such file or directory" error. 
    145145 
    146146Also note that the script assumes that _all_ the eeproms belong to DIMMs, 
    147147which may not be the case. 
     148 
     149 
     150Decode-vaio.pl 
     151-------------- 
     152 
     153This Perl script looks for a Sony Vaio EEPROM at 0x57. If your system is not 
     154a Sony Vaio laptop, you just don't care. If your system is an old Vaio, you 
     155probably don't have an EEPROM on it and this script will be useless to you 
     156as well. 
     157 
     158Use: 
     159 
     160After inserting the necessary modules, run the script! 
     161 
     162Notes: 
     163 
     164The script assumes that Perl can be found at /usr/bin/perl.  If different, 
     165you will need to adjust the first line of the file accordingly, or else 
     166you will get a strange "decode-vaio.pl: no such file or directory" error.