include/hw/registerfields.h

   1 /*
   2  * Register Definition API: field macros
   3  *
   4  * Copyright (c) 2016 Xilinx Inc.
   5  * Copyright (c) 2013 Peter Crosthwaite <[email protected]>
   6  *
   7  * This work is licensed under the terms of the GNU GPL, version 2.  See
   8  * the COPYING file in the top-level directory.
   9  */
  10
  11 #ifndef REGISTERFIELDS_H
  12 #define REGISTERFIELDS_H
  13
  14 #include "qemu/bitops.h"
  15
  16 /* Define constants for a 32 bit register */
  17
  18 /* This macro will define A_FOO, for the byte address of a register
  19  * as well as R_FOO for the uint32_t[] register number (A_FOO / 4).
  20  */
  21 #define REG32(reg, addr)                                                  \
  22     enum { A_ ## reg = (addr) };                                          \
  23     enum { R_ ## reg = (addr) / 4 };
  24
  25 /* Define SHIFT, LENGTH and MASK constants for a field within a register */
  26
  27 /* This macro will define R_FOO_BAR_MASK, R_FOO_BAR_SHIFT and R_FOO_BAR_LENGTH
  28  * constants for field BAR in register FOO.
  29  */
  30 #define FIELD(reg, field, shift, length)                                  \
  31     enum { R_ ## reg ## _ ## field ## _SHIFT = (shift)};                  \
  32     enum { R_ ## reg ## _ ## field ## _LENGTH = (length)};                \
  33     enum { R_ ## reg ## _ ## field ## _MASK =                             \
  34                                         MAKE_64BIT_MASK(shift, length)};
  35
  36 /* Extract a field from a register */
  37 #define FIELD_EX32(storage, reg, field)                                   \
  38     extract32((storage), R_ ## reg ## _ ## field ## _SHIFT,               \
  39               R_ ## reg ## _ ## field ## _LENGTH)
  40 #define FIELD_EX64(storage, reg, field)                                   \
  41     extract64((storage), R_ ## reg ## _ ## field ## _SHIFT,               \
  42               R_ ## reg ## _ ## field ## _LENGTH)
  43
  44 /* Extract a field from an array of registers */
  45 #define ARRAY_FIELD_EX32(regs, reg, field)                                \
  46     FIELD_EX32((regs)[R_ ## reg], reg, field)
  47
  48 /* Deposit a register field.
  49  * Assigning values larger then the target field will result in
  50  * compilation warnings.
  51  */
  52 #define FIELD_DP32(storage, reg, field, val) ({                           \
  53     struct {                                                              \
  54         unsigned int v:R_ ## reg ## _ ## field ## _LENGTH;                \
  55     } v = { .v = val };                                                   \
  56     uint32_t d;                                                           \
  57     d = deposit32((storage), R_ ## reg ## _ ## field ## _SHIFT,           \
  58                   R_ ## reg ## _ ## field ## _LENGTH, v.v);               \
  59     d; })
  60 #define FIELD_DP64(storage, reg, field, val) ({                           \
  61     struct {                                                              \
  62         unsigned int v:R_ ## reg ## _ ## field ## _LENGTH;                \
  63     } v = { .v = val };                                                   \
  64     uint64_t d;                                                           \
  65     d = deposit64((storage), R_ ## reg ## _ ## field ## _SHIFT,           \
  66                   R_ ## reg ## _ ## field ## _LENGTH, v.v);               \
  67     d; })
  68
  69 /* Deposit a field to array of registers.  */
  70 #define ARRAY_FIELD_DP32(regs, reg, field, val)                           \
  71     (regs)[R_ ## reg] = FIELD_DP32((regs)[R_ ## reg], reg, field, val);
  72
  73 #endif