drivers/gator/gator_buffer_write.c

   1 /**
   2  * Copyright (C) ARM Limited 2010-2014. All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  */
   9
  10 static void gator_buffer_write_packed_int(int cpu, int buftype, int x)
  11 {
  12         uint32_t write = per_cpu(gator_buffer_write, cpu)[buftype];
  13         uint32_t mask = gator_buffer_mask[buftype];
  14         char *buffer = per_cpu(gator_buffer, cpu)[buftype];
  15         int packedBytes = 0;
  16         int more = true;
  17         while (more) {
  18                 // low order 7 bits of x
  19                 char b = x & 0x7f;
  20                 x >>= 7;
  21
  22                 if ((x == 0 && (b & 0x40) == 0) || (x == -1 && (b & 0x40) != 0)) {
  23                         more = false;
  24                 } else {
  25                         b |= 0x80;
  26                 }
  27
  28                 buffer[(write + packedBytes) & mask] = b;
  29                 packedBytes++;
  30         }
  31
  32         per_cpu(gator_buffer_write, cpu)[buftype] = (write + packedBytes) & mask;
  33 }
  34
  35 static void gator_buffer_write_packed_int64(int cpu, int buftype, long long x)
  36 {
  37         uint32_t write = per_cpu(gator_buffer_write, cpu)[buftype];
  38         uint32_t mask = gator_buffer_mask[buftype];
  39         char *buffer = per_cpu(gator_buffer, cpu)[buftype];
  40         int packedBytes = 0;
  41         int more = true;
  42         while (more) {
  43                 // low order 7 bits of x
  44                 char b = x & 0x7f;
  45                 x >>= 7;
  46
  47                 if ((x == 0 && (b & 0x40) == 0) || (x == -1 && (b & 0x40) != 0)) {
  48                         more = false;
  49                 } else {
  50                         b |= 0x80;
  51                 }
  52
  53                 buffer[(write + packedBytes) & mask] = b;
  54                 packedBytes++;
  55         }
  56
  57         per_cpu(gator_buffer_write, cpu)[buftype] = (write + packedBytes) & mask;
  58 }
  59
  60 static void gator_buffer_write_bytes(int cpu, int buftype, const char *x, int len)
  61 {
  62         int i;
  63         u32 write = per_cpu(gator_buffer_write, cpu)[buftype];
  64         u32 mask = gator_buffer_mask[buftype];
  65         char *buffer = per_cpu(gator_buffer, cpu)[buftype];
  66
  67         for (i = 0; i < len; i++) {
  68                 buffer[write] = x[i];
  69                 write = (write + 1) & mask;
  70         }
  71
  72         per_cpu(gator_buffer_write, cpu)[buftype] = write;
  73 }
  74
  75 static void gator_buffer_write_string(int cpu, int buftype, const char *x)
  76 {
  77         int len = strlen(x);
  78         gator_buffer_write_packed_int(cpu, buftype, len);
  79         gator_buffer_write_bytes(cpu, buftype, x, len);
  80 }