libgram/README.md

   1 # libgram, the C companion for gram
   2
   3 libgram is the C library for gram core initialization and calibration.
   4
   5 ## HowTo
   6
   7 Build libgram with make. In your firmware:
   8
   9 ```C
  10 #include <gram.h>
  11
  12 int main(void) {
  13         struct gramCtx ctx;
  14         struct gramProfile profile {
  15                 .mode_registers = {
  16                         0x320, 0x6, 0x200, 0
  17                 },
  18                 .rdly_p0 = 0,
  19                 .rdly_p1 = 0
  20         };
  21         int err = gram_init(&ctx, &profile, 0x10000000, 0x00006000, 0x00005000);
  22
  23         return 0;
  24 }
  25 ```
  26
  27 Link it to this library and you should be good to go!
  28
  29 ## Error handling
  30
  31 ```
  32 GRAM_ERR_NONE: No error happened (hardcoded to zero)
  33 GRAM_ERR_UNDOCUMENTED: Undocumented error, shame on us lazy coders (take a look at the code)
  34 GRAM_ERR_RDLY_MAX: Read delay calibration unsuccessful because its value exceeds DQSBUFM's max
  35 ```
  36
  37 ## Using libgram outside the SoC
  38
  39 Compile libgram with `CFLAGS="-DGRAM_RW_FUNC"` (run `make clean` beforehand) and define the following bus access functions:
  40
  41 ```c
  42 uint32_t gram_read(struct gramCtx *ctx, void *addr);
  43 int gram_write(struct gramCtx *ctx, void *addr, uint32_t value);
  44 ```
  45
  46 If you want to use the default compiler on your computer, use `CFLAGS="-DGRAM_RW_FUNC" make TRIPLE=""`.