usrp: added control for sr based i2c core

3 files changed, 194 insertions, 0 deletions

diff --git a/host/lib/usrp/cores/CMakeLists.txt b/host/lib/usrp/cores/CMakeLists.txt
index aa5f0bcbb..3192b0774 100644
--- a/host/lib/usrp/cores/CMakeLists.txt
+++ b/host/lib/usrp/cores/CMakeLists.txt
@@ -24,6 +24,7 @@ INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR})
 LIBUHD_APPEND_SOURCES(
     ${CMAKE_CURRENT_SOURCE_DIR}/gpio_core_200.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/i2c_core_100.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/i2c_core_200.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/spi_core_100.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/time64_core_200.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/rx_dsp_core_200.cpp
diff --git a/host/lib/usrp/cores/i2c_core_200.cpp b/host/lib/usrp/cores/i2c_core_200.cpp
new file mode 100644
index 000000000..1b882c54a
--- /dev/null
+++ b/host/lib/usrp/cores/i2c_core_200.cpp
@@ -0,0 +1,158 @@
+//
+// Copyright 2011-2012 Ettus Research LLC
+//
+// 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 3 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 "i2c_core_200.hpp"
+#include <uhd/exception.hpp>
+#include <uhd/utils/msg.hpp>
+#include <boost/thread/thread.hpp> //sleep
+#include <boost/thread/mutex.hpp>
+
+#define REG_I2C_WR_PRESCALER_LO (1 << 3) | 0
+#define REG_I2C_WR_PRESCALER_HI (1 << 3) | 1
+#define REG_I2C_WR_CTRL         (1 << 3) | 2
+#define REG_I2C_WR_DATA         (1 << 3) | 3
+#define REG_I2C_WR_CMD          (1 << 3) | 4
+#define REG_I2C_RD_DATA         (0 << 3) | 3
+#define REG_I2C_RD_ST           (0 << 3) | 4
+
+//
+// STA, STO, RD, WR, and IACK bits are cleared automatically
+//
+
+#define	I2C_CTRL_EN	(1 << 7)	// core enable
+#define	I2C_CTRL_IE	(1 << 6)	// interrupt enable
+
+#define	I2C_CMD_START	(1 << 7)	// generate (repeated) start condition
+#define I2C_CMD_STOP	(1 << 6)	// generate stop condition
+#define	I2C_CMD_RD	(1 << 5)	// read from slave
+#define I2C_CMD_WR	(1 << 4)	// write to slave
+#define	I2C_CMD_NACK	(1 << 3)	// when a rcvr, send ACK (ACK=0) or NACK (ACK=1)
+#define I2C_CMD_RSVD_2	(1 << 2)	// reserved
+#define	I2C_CMD_RSVD_1	(1 << 1)	// reserved
+#define I2C_CMD_IACK	(1 << 0)	// set to clear pending interrupt
+
+#define I2C_ST_RXACK	(1 << 7)	// Received acknowledgement from slave (1 = NAK, 0 = ACK)
+#define	I2C_ST_BUSY	(1 << 6)	// 1 after START signal detected; 0 after STOP signal detected
+#define	I2C_ST_AL	(1 << 5)	// Arbitration lost.  1 when core lost arbitration
+#define	I2C_ST_RSVD_4	(1 << 4)	// reserved
+#define	I2C_ST_RSVD_3	(1 << 3)	// reserved
+#define	I2C_ST_RSVD_2	(1 << 2)	// reserved
+#define I2C_ST_TIP	(1 << 1)	// Transfer-in-progress
+#define	I2C_ST_IP	(1 << 0)	// Interrupt pending
+
+using namespace uhd;
+
+class i2c_core_200_impl : public i2c_core_200{
+public:
+    i2c_core_200_impl(wb_iface::sptr iface, const size_t base, const size_t readback):
+        _iface(iface), _base(base), _readback(readback)
+    {
+        //init I2C FPGA interface.
+        this->poke(REG_I2C_WR_CTRL, 0x0000);
+        //set prescalers to operate at 400kHz: WB_CLK is 64MHz...
+        static const boost::uint32_t i2c_datarate = 400000;
+        static const boost::uint32_t wishbone_clk = 64000000; //FIXME should go somewhere else
+        boost::uint16_t prescaler = wishbone_clk / (i2c_datarate*5) - 1;
+        this->poke(REG_I2C_WR_PRESCALER_LO, prescaler & 0xFF);
+        this->poke(REG_I2C_WR_PRESCALER_HI, (prescaler >> 8) & 0xFF);
+        this->poke(REG_I2C_WR_CTRL, I2C_CTRL_EN); //enable I2C core
+    }
+
+    void write_i2c(
+        boost::uint8_t addr,
+        const byte_vector_t &bytes
+    ){
+        this->poke(REG_I2C_WR_DATA, (addr << 1) | 0); //addr and read bit (0)
+        this->poke(REG_I2C_WR_CMD, I2C_CMD_WR | I2C_CMD_START | (bytes.size() == 0 ? I2C_CMD_STOP : 0));
+
+        //wait for previous transfer to complete
+        if (not wait_chk_ack()) {
+            this->poke(REG_I2C_WR_CMD, I2C_CMD_STOP);
+            return;
+        }
+
+        for (size_t i = 0; i < bytes.size(); i++) {
+            this->poke(REG_I2C_WR_DATA, bytes[i]);
+            this->poke(REG_I2C_WR_CMD, I2C_CMD_WR | ((i == (bytes.size() - 1)) ? I2C_CMD_STOP : 0));
+            if(!wait_chk_ack()) {
+                this->poke(REG_I2C_WR_CMD, I2C_CMD_STOP);
+                return;
+            }
+        }
+    }
+
+    byte_vector_t read_i2c(
+        boost::uint8_t addr,
+        size_t num_bytes
+    ){
+        byte_vector_t bytes;
+        if (num_bytes == 0) return bytes;
+
+        while (this->peek(REG_I2C_RD_ST) & I2C_ST_BUSY){
+            /* NOP */
+        }
+
+        this->poke(REG_I2C_WR_DATA, (addr << 1) | 1); //addr and read bit (1)
+        this->poke(REG_I2C_WR_CMD, I2C_CMD_WR | I2C_CMD_START);
+        //wait for previous transfer to complete
+        if (not wait_chk_ack()) {
+            this->poke(REG_I2C_WR_CMD, I2C_CMD_STOP);
+        }
+        for (size_t i = 0; i < num_bytes; i++) {
+            this->poke(REG_I2C_WR_CMD, I2C_CMD_RD | ((num_bytes == i+1) ? (I2C_CMD_STOP | I2C_CMD_NACK) : 0));
+            i2c_wait();
+            bytes.push_back(this->peek(REG_I2C_RD_DATA));
+        }
+        return bytes;
+    }
+
+private:
+    void i2c_wait(void) {
+        for (size_t i = 0; i < 100; i++){
+            if ((this->peek(REG_I2C_RD_ST) & I2C_ST_TIP) == 0) return;
+            boost::this_thread::sleep(boost::posix_time::milliseconds(1));
+        }
+        UHD_MSG(error) << "i2c_core_200: i2c_wait timeout" << std::endl;
+    }
+
+    bool wait_chk_ack(void){
+        i2c_wait();
+        return (this->peek(REG_I2C_RD_ST) & I2C_ST_RXACK) == 0;
+    }
+
+    void poke(const size_t what, const boost::uint8_t cmd)
+    {
+        boost::mutex::scoped_lock lock(_mutex);
+        _iface->poke32(_base, (what << 8) | cmd);
+    }
+
+    boost::uint8_t peek(const size_t what)
+    {
+        boost::mutex::scoped_lock lock(_mutex);
+        _iface->poke32(_base, what << 8);
+        return boost::uint8_t(_iface->peek32(_readback));
+    }
+
+    wb_iface::sptr _iface;
+    const size_t _base;
+    const size_t _readback;
+    boost::mutex _mutex;
+};
+
+i2c_core_200::sptr i2c_core_200::make(wb_iface::sptr iface, const size_t base, const size_t readback){
+    return sptr(new i2c_core_200_impl(iface, base, readback));
+}
diff --git a/host/lib/usrp/cores/i2c_core_200.hpp b/host/lib/usrp/cores/i2c_core_200.hpp
new file mode 100644
index 000000000..508855985
--- /dev/null
+++ b/host/lib/usrp/cores/i2c_core_200.hpp
@@ -0,0 +1,35 @@
+//
+// Copyright 2011-2012 Ettus Research LLC
+//
+// 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 3 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/>.
+//
+
+#ifndef INCLUDED_LIBUHD_USRP_I2C_CORE_200_HPP
+#define INCLUDED_LIBUHD_USRP_I2C_CORE_200_HPP
+
+#include <uhd/config.hpp>
+#include <uhd/types/serial.hpp>
+#include <boost/utility.hpp>
+#include <boost/shared_ptr.hpp>
+#include "wb_iface.hpp"
+
+class i2c_core_200 : boost::noncopyable, public uhd::i2c_iface{
+public:
+    typedef boost::shared_ptr<i2c_core_200> sptr;
+
+    //! makes a new i2c core from iface and slave base
+    static sptr make(wb_iface::sptr iface, const size_t base, const size_t readback);
+};
+
+#endif /* INCLUDED_LIBUHD_USRP_I2C_CORE_200_HPP */