i.MX: Add qtest support for I2C device emulator.

This is using a ds1338 RTC chip on the I2C bus. This RTC chip is
not present on the real 3DS PDK board.

Signed-off-by: Jean-Christophe Dubois <jcd@tribudubois.net>
Acked-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Message-id: 05601683a2a95c881cbc9f22651a044d969bd0ae.1441057361.git.jcd@tribudubois.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 212 insertions, 0 deletions

diff --git a/tests/libqos/i2c-imx.c b/tests/libqos/i2c-imx.c
new file mode 100644
index 0000000..b5cef66
--- /dev/null
+++ b/tests/libqos/i2c-imx.c
@@ -0,0 +1,209 @@
+/*
+ * QTest i.MX I2C driver
+ *
+ * Copyright (c) 2013 Jean-Christophe Dubois
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under the terms of the GNU General Public License as published by the
+ *  Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful, but WITHOUT
+ *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ *  FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ *  for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "libqos/i2c.h"
+
+#include <glib.h>
+#include <string.h>
+
+#include "qemu/osdep.h"
+#include "libqtest.h"
+
+#include "hw/i2c/imx_i2c.h"
+
+enum IMXI2CDirection {
+    IMX_I2C_READ,
+    IMX_I2C_WRITE,
+};
+
+typedef struct IMXI2C {
+    I2CAdapter parent;
+
+    uint64_t addr;
+} IMXI2C;
+
+
+static void imx_i2c_set_slave_addr(IMXI2C *s, uint8_t addr,
+                                   enum IMXI2CDirection direction)
+{
+    writeb(s->addr + I2DR_ADDR, (addr << 1) |
+           (direction == IMX_I2C_READ ? 1 : 0));
+}
+
+static void imx_i2c_send(I2CAdapter *i2c, uint8_t addr,
+                         const uint8_t *buf, uint16_t len)
+{
+    IMXI2C *s = (IMXI2C *)i2c;
+    uint8_t data;
+    uint8_t status;
+    uint16_t size = 0;
+
+    if (!len) {
+        return;
+    }
+
+    /* set the bus for write */
+    data = I2CR_IEN |
+           I2CR_IIEN |
+           I2CR_MSTA |
+           I2CR_MTX |
+           I2CR_TXAK;
+
+    writeb(s->addr + I2CR_ADDR, data);
+    status = readb(s->addr + I2SR_ADDR);
+    g_assert((status & I2SR_IBB) != 0);
+
+    /* set the slave address */
+    imx_i2c_set_slave_addr(s, addr, IMX_I2C_WRITE);
+    status = readb(s->addr + I2SR_ADDR);
+    g_assert((status & I2SR_IIF) != 0);
+    g_assert((status & I2SR_RXAK) == 0);
+
+    /* ack the interrupt */
+    writeb(s->addr + I2SR_ADDR, 0);
+    status = readb(s->addr + I2SR_ADDR);
+    g_assert((status & I2SR_IIF) == 0);
+
+    while (size < len) {
+        /* check we are still busy */
+        status = readb(s->addr + I2SR_ADDR);
+        g_assert((status & I2SR_IBB) != 0);
+
+        /* write the data */
+        writeb(s->addr + I2DR_ADDR, buf[size]);
+        status = readb(s->addr + I2SR_ADDR);
+        g_assert((status & I2SR_IIF) != 0);
+        g_assert((status & I2SR_RXAK) == 0);
+
+        /* ack the interrupt */
+        writeb(s->addr + I2SR_ADDR, 0);
+        status = readb(s->addr + I2SR_ADDR);
+        g_assert((status & I2SR_IIF) == 0);
+
+        size++;
+    }
+
+    /* release the bus */
+    data &= ~(I2CR_MSTA | I2CR_MTX);
+    writeb(s->addr + I2CR_ADDR, data);
+    status = readb(s->addr + I2SR_ADDR);
+    g_assert((status & I2SR_IBB) == 0);
+}
+
+static void imx_i2c_recv(I2CAdapter *i2c, uint8_t addr,
+                         uint8_t *buf, uint16_t len)
+{
+    IMXI2C *s = (IMXI2C *)i2c;
+    uint8_t data;
+    uint8_t status;
+    uint16_t size = 0;
+
+    if (!len) {
+        return;
+    }
+
+    /* set the bus for write */
+    data = I2CR_IEN |
+           I2CR_IIEN |
+           I2CR_MSTA |
+           I2CR_MTX |
+           I2CR_TXAK;
+
+    writeb(s->addr + I2CR_ADDR, data);
+    status = readb(s->addr + I2SR_ADDR);
+    g_assert((status & I2SR_IBB) != 0);
+
+    /* set the slave address */
+    imx_i2c_set_slave_addr(s, addr, IMX_I2C_READ);
+    status = readb(s->addr + I2SR_ADDR);
+    g_assert((status & I2SR_IIF) != 0);
+    g_assert((status & I2SR_RXAK) == 0);
+
+    /* ack the interrupt */
+    writeb(s->addr + I2SR_ADDR, 0);
+    status = readb(s->addr + I2SR_ADDR);
+    g_assert((status & I2SR_IIF) == 0);
+
+    /* set the bus for read */
+    data &= ~I2CR_MTX;
+    /* if only one byte don't ack */
+    if (len != 1) {
+        data &= ~I2CR_TXAK;
+    }
+    writeb(s->addr + I2CR_ADDR, data);
+    status = readb(s->addr + I2SR_ADDR);
+    g_assert((status & I2SR_IBB) != 0);
+
+    /* dummy read */
+    readb(s->addr + I2DR_ADDR);
+    status = readb(s->addr + I2SR_ADDR);
+    g_assert((status & I2SR_IIF) != 0);
+
+    /* ack the interrupt */
+    writeb(s->addr + I2SR_ADDR, 0);
+    status = readb(s->addr + I2SR_ADDR);
+    g_assert((status & I2SR_IIF) == 0);
+
+    while (size < len) {
+        /* check we are still busy */
+        status = readb(s->addr + I2SR_ADDR);
+        g_assert((status & I2SR_IBB) != 0);
+
+        if (size == (len - 1)) {
+            /* stop the read transaction */
+            data &= ~(I2CR_MSTA | I2CR_MTX);
+        } else {
+            /* ack the data read */
+            data |= I2CR_TXAK;
+        }
+        writeb(s->addr + I2CR_ADDR, data);
+
+        /* read the data */
+        buf[size] = readb(s->addr + I2DR_ADDR);
+
+        if (size != (len - 1)) {
+            status = readb(s->addr + I2SR_ADDR);
+            g_assert((status & I2SR_IIF) != 0);
+
+            /* ack the interrupt */
+            writeb(s->addr + I2SR_ADDR, 0);
+        }
+
+        status = readb(s->addr + I2SR_ADDR);
+        g_assert((status & I2SR_IIF) == 0);
+
+        size++;
+    }
+
+    status = readb(s->addr + I2SR_ADDR);
+    g_assert((status & I2SR_IBB) == 0);
+}
+
+I2CAdapter *imx_i2c_create(uint64_t addr)
+{
+    IMXI2C *s = g_malloc0(sizeof(*s));
+    I2CAdapter *i2c = (I2CAdapter *)s;
+
+    s->addr = addr;
+
+    i2c->send = imx_i2c_send;
+    i2c->recv = imx_i2c_recv;
+
+    return i2c;
+}
diff --git a/tests/libqos/i2c.h b/tests/libqos/i2c.h
index 1ce9af4..c21f1dc 100644
--- a/tests/libqos/i2c.h
+++ b/tests/libqos/i2c.h
@@ -27,4 +27,7 @@ void i2c_recv(I2CAdapter *i2c, uint8_t addr,
 /* libi2c-omap.c */
 I2CAdapter *omap_i2c_create(uint64_t addr);
 
+/* libi2c-imx.c */
+I2CAdapter *imx_i2c_create(uint64_t addr);
+
 #endif