tests/libi2c-omap.c

   1 /*
   2  * QTest I2C driver
   3  *
   4  * Copyright (c) 2012 Andreas Färber
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
   7  * See the COPYING file in the top-level directory.
   8  */
   9 #include "libi2c.h"
  10
  11 #include <glib.h>
  12 #include <string.h>
  13
  14 #include "qemu/osdep.h"
  15 #include "qemu/bswap.h"
  16 #include "libqtest.h"
  17
  18 enum OMAPI2CRegisters {
  19     OMAP_I2C_REV  = 0x00,
  20     OMAP_I2C_STAT = 0x08,
  21     OMAP_I2C_CNT  = 0x18,
  22     OMAP_I2C_DATA = 0x1c,
  23     OMAP_I2C_CON  = 0x24,
  24     OMAP_I2C_SA   = 0x2c,
  25 };
  26
  27 enum OMAPI2CSTATBits {
  28     OMAP_I2C_STAT_NACK = 1 << 1,
  29     OMAP_I2C_STAT_ARDY = 1 << 2,
  30     OMAP_I2C_STAT_RRDY = 1 << 3,
  31     OMAP_I2C_STAT_XRDY = 1 << 4,
  32     OMAP_I2C_STAT_ROVR = 1 << 11,
  33     OMAP_I2C_STAT_SBD  = 1 << 15,
  34 };
  35
  36 enum OMAPI2CCONBits {
  37     OMAP_I2C_CON_STT    = 1 << 0,
  38     OMAP_I2C_CON_STP    = 1 << 1,
  39     OMAP_I2C_CON_TRX    = 1 << 9,
  40     OMAP_I2C_CON_MST    = 1 << 10,
  41     OMAP_I2C_CON_BE     = 1 << 14,
  42     OMAP_I2C_CON_I2C_EN = 1 << 15,
  43 };
  44
  45 typedef struct OMAPI2C {
  46     I2CAdapter parent;
  47
  48     uint64_t addr;
  49 } OMAPI2C;
  50
  51
  52 /* FIXME Use TBD readw qtest API */
  53 static inline uint16_t readw(uint64_t addr)
  54 {
  55     uint16_t data;
  56
  57     memread(addr, &data, 2);
  58     return le16_to_cpu(data);
  59 }
  60
  61 /* FIXME Use TBD writew qtest API */
  62 static inline void writew(uint64_t addr, uint16_t data)
  63 {
  64     data = cpu_to_le16(data);
  65     memwrite(addr, &data, 2);
  66 }
  67
  68 #ifdef __GNUC__
  69 #undef memread
  70 #undef memwrite
  71 #pragma GCC poison memread
  72 #pragma GCC poison memwrite
  73 #endif
  74
  75 static void omap_i2c_set_slave_addr(OMAPI2C *s, uint8_t addr)
  76 {
  77     uint16_t data = addr;
  78
  79     writew(s->addr + OMAP_I2C_SA, data);
  80     data = readw(s->addr + OMAP_I2C_SA);
  81     g_assert_cmphex(data, ==, addr);
  82 }
  83
  84 static void omap_i2c_send(I2CAdapter *i2c, uint8_t addr,
  85                           const uint8_t *buf, uint16_t len)
  86 {
  87     OMAPI2C *s = (OMAPI2C *)i2c;
  88     uint16_t data;
  89
  90     omap_i2c_set_slave_addr(s, addr);
  91
  92     data = len;
  93     writew(s->addr + OMAP_I2C_CNT, data);
  94
  95     data = OMAP_I2C_CON_I2C_EN |
  96            OMAP_I2C_CON_TRX |
  97            OMAP_I2C_CON_MST |
  98            OMAP_I2C_CON_STT |
  99            OMAP_I2C_CON_STP;
 100     writew(s->addr + OMAP_I2C_CON, data);
 101     data = readw(s->addr + OMAP_I2C_CON);
 102     g_assert((data & OMAP_I2C_CON_STP) != 0);
 103
 104     data = readw(s->addr + OMAP_I2C_STAT);
 105     g_assert((data & OMAP_I2C_STAT_NACK) == 0);
 106
 107     while (len > 1) {
 108         data = readw(s->addr + OMAP_I2C_STAT);
 109         g_assert((data & OMAP_I2C_STAT_XRDY) != 0);
 110
 111         data = buf[0] | ((uint16_t)buf[1] << 8);
 112         writew(s->addr + OMAP_I2C_DATA, data);
 113         buf = (uint8_t *)buf + 2;
 114         len -= 2;
 115     }
 116     if (len == 1) {
 117         data = readw(s->addr + OMAP_I2C_STAT);
 118         g_assert((data & OMAP_I2C_STAT_XRDY) != 0);
 119
 120         data = buf[0];
 121         writew(s->addr + OMAP_I2C_DATA, data);
 122     }
 123
 124     data = readw(s->addr + OMAP_I2C_CON);
 125     g_assert((data & OMAP_I2C_CON_STP) == 0);
 126 }
 127
 128 static void omap_i2c_recv(I2CAdapter *i2c, uint8_t addr,
 129                           uint8_t *buf, uint16_t len)
 130 {
 131     OMAPI2C *s = (OMAPI2C *)i2c;
 132     uint16_t data, stat;
 133
 134     omap_i2c_set_slave_addr(s, addr);
 135
 136     data = len;
 137     writew(s->addr + OMAP_I2C_CNT, data);
 138
 139     data = OMAP_I2C_CON_I2C_EN |
 140            OMAP_I2C_CON_MST |
 141            OMAP_I2C_CON_STT |
 142            OMAP_I2C_CON_STP;
 143     writew(s->addr + OMAP_I2C_CON, data);
 144     data = readw(s->addr + OMAP_I2C_CON);
 145     g_assert((data & OMAP_I2C_CON_STP) == 0);
 146
 147     data = readw(s->addr + OMAP_I2C_STAT);
 148     g_assert((data & OMAP_I2C_STAT_NACK) == 0);
 149
 150     data = readw(s->addr + OMAP_I2C_CNT);
 151     g_assert_cmpuint(data, ==, len);
 152
 153     while (len > 0) {
 154         data = readw(s->addr + OMAP_I2C_STAT);
 155         g_assert((data & OMAP_I2C_STAT_RRDY) != 0);
 156         g_assert((data & OMAP_I2C_STAT_ROVR) == 0);
 157
 158         data = readw(s->addr + OMAP_I2C_DATA);
 159
 160         stat = readw(s->addr + OMAP_I2C_STAT);
 161
 162         if (unlikely(len == 1)) {
 163             g_assert((stat & OMAP_I2C_STAT_SBD) != 0);
 164
 165             buf[0] = data & 0xff;
 166             buf++;
 167             len--;
 168         } else {
 169             buf[0] = data & 0xff;
 170             buf[1] = data >> 8;
 171             buf += 2;
 172             len -= 2;
 173         }
 174     }
 175
 176     data = readw(s->addr + OMAP_I2C_CON);
 177     g_assert((data & OMAP_I2C_CON_STP) == 0);
 178 }
 179
 180 I2CAdapter *omap_i2c_create(uint64_t addr)
 181 {
 182     OMAPI2C *s = g_malloc0(sizeof(*s));
 183     I2CAdapter *i2c = (I2CAdapter *)s;
 184     uint16_t data;
 185
 186     s->addr = addr;
 187
 188     i2c->send = omap_i2c_send;
 189     i2c->recv = omap_i2c_recv;
 190
 191     /* verify the mmio address by looking for a known signature */
 192     data = readw(addr + OMAP_I2C_REV);
 193     g_assert_cmphex(data, ==, 0x34);
 194
 195     return i2c;
 196 }