xilinx: Add ethlite emulation.

Signed-off-by: NEdgar E. Iglesias <edgar.iglesias@gmail.com>

hw/xilinx_ethlite.c

+/*
+ * QEMU model of the Xilinx Ethernet Lite MAC.
+ *
+ * Copyright (c) 2009 Edgar E. Iglesias.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "sysbus.h"
+#include "hw.h"
+#include "net.h"
+
+#define D(x)
+#define R_TX_BUF0     0
+#define R_TX_LEN0     (0x07f4 / 4)
+#define R_TX_GIE0     (0x07f8 / 4)
+#define R_TX_CTRL0    (0x07fc / 4)
+#define R_TX_BUF1     (0x0800 / 4)
+#define R_TX_LEN1     (0x0ff4 / 4)
+#define R_TX_CTRL1    (0x0ffc / 4)
+
+#define R_RX_BUF0     (0x1000 / 4)
+#define R_RX_CTRL0    (0x17fc / 4)
+#define R_RX_BUF1     (0x1800 / 4)
+#define R_RX_CTRL1    (0x1ffc / 4)
+#define R_MAX         (0x2000 / 4)
+
+#define GIE_GIE    0x80000000
+
+#define CTRL_I     0x8
+#define CTRL_P     0x2
+#define CTRL_S     0x1
+
+struct xlx_ethlite
+{
+    SysBusDevice busdev;
+    qemu_irq irq;
+    VLANClientState *vc;
+
+    unsigned int c_tx_pingpong;
+    unsigned int c_rx_pingpong;
+    unsigned int txbuf;
+    unsigned int rxbuf;
+
+    uint8_t macaddr[6];
+    uint32_t regs[R_MAX];
+};
+
+static inline void eth_pulse_irq(struct xlx_ethlite *s)
+{
+    /* Only the first gie reg is active.  */
+    if (s->regs[R_TX_GIE0] & GIE_GIE) {
+        qemu_irq_pulse(s->irq);
+    }
+}
+
+static uint32_t eth_readl (void *opaque, target_phys_addr_t addr)
+{
+    struct xlx_ethlite *s = opaque;
+    uint32_t r = 0;
+
+    addr >>= 2;
+
+    switch (addr)
+    {
+        case R_TX_GIE0:
+        case R_TX_LEN0:
+        case R_TX_LEN1:
+        case R_TX_CTRL1:
+        case R_TX_CTRL0:
+        case R_RX_CTRL1:
+        case R_RX_CTRL0:
+            r = s->regs[addr];
+            D(qemu_log("%s %x=%x\n", __func__, addr * 4, r));
+            break;
+
+        /* Rx packet data is endian fixed at the way into the rx rams. This
+         * speeds things up because the ethlite MAC does not have a len
+         * register. That means the CPU will issue MMIO reads for the entire
+         * 2k rx buffer even for small packets.
+         */
+        default:
+            r = s->regs[addr];
+            break;
+    }
+    return r;
+}
+
+static void
+eth_writel (void *opaque, target_phys_addr_t addr, uint32_t value)
+{
+    struct xlx_ethlite *s = opaque;
+    unsigned int base = 0;
+
+    addr >>= 2;
+    switch (addr) 
+    {
+        case R_TX_CTRL0:
+        case R_TX_CTRL1:
+            if (addr == R_TX_CTRL1)
+                base = 0x800 / 4;
+
+            D(qemu_log("%s addr=%x val=%x\n", __func__, addr * 4, value));
+            if ((value & (CTRL_P | CTRL_S)) == CTRL_S) {
+                qemu_send_packet(s->vc,
+                                 (void *) &s->regs[base],
+                                 s->regs[base + R_TX_LEN0]);
+                D(qemu_log("eth_tx %d\n", s->regs[base + R_TX_LEN0]));
+                if (s->regs[base + R_TX_CTRL0] & CTRL_I)
+                    eth_pulse_irq(s);
+            } else if ((value & (CTRL_P | CTRL_S)) == (CTRL_P | CTRL_S)) {
+                memcpy(&s->macaddr[0], &s->regs[base], 6);
+                if (s->regs[base + R_TX_CTRL0] & CTRL_I)
+                    eth_pulse_irq(s);
+            }
+
+            /* We are fast and get ready pretty much immediately so
+               we actually never flip the S nor P bits to one.  */
+            s->regs[addr] = value & ~(CTRL_P | CTRL_S);
+            break;
+
+        /* Keep these native.  */
+        case R_TX_LEN0:
+        case R_TX_LEN1:
+        case R_TX_GIE0:
+        case R_RX_CTRL0:
+        case R_RX_CTRL1:
+            D(qemu_log("%s addr=%x val=%x\n", __func__, addr * 4, value));
+            s->regs[addr] = value;
+            break;
+
+        /* Packet data, make sure it stays BE.  */
+        default:
+            s->regs[addr] = cpu_to_be32(value);
+            break;
+    }
+}
+
+static CPUReadMemoryFunc *eth_read[] = {
+    NULL, NULL, &eth_readl,
+};
+
+static CPUWriteMemoryFunc *eth_write[] = {
+    NULL, NULL, &eth_writel,
+};
+
+static int eth_can_rx(void *opaque)
+{
+    struct xlx_ethlite *s = opaque;
+    int r;
+    r = !(s->regs[R_RX_CTRL0] & CTRL_S);
+    qemu_log("%s %d\n", __func__, r);
+    return r;
+}
+
+static void eth_rx(void *opaque, const uint8_t *buf, int size)
+{
+    struct xlx_ethlite *s = opaque;
+    unsigned int rxbase = s->rxbuf * (0x800 / 4);
+    int i;
+
+    /* DA filter.  */
+    if (!(buf[0] & 0x80) && memcmp(&s->macaddr[0], buf, 6))
+        return;
+
+    if (s->regs[rxbase + R_RX_CTRL0] & CTRL_S) {
+        D(qemu_log("ethlite lost packet %x\n", s->regs[R_RX_CTRL0]));
+        return;
+    }
+
+    D(qemu_log("%s %d rxbase=%x\n", __func__, size, rxbase));
+    memcpy(&s->regs[rxbase + R_RX_BUF0], buf, size);
+
+    /* Bring it into host endianess.  */
+    for (i = 0; i < ((size + 3) / 4); i++) {
+       uint32_t d = s->regs[rxbase + R_RX_BUF0 + i];
+       s->regs[rxbase + R_RX_BUF0 + i] = be32_to_cpu(d);
+    }
+
+    s->regs[rxbase + R_RX_CTRL0] |= CTRL_S;
+    if (s->regs[rxbase + R_RX_CTRL0] & CTRL_I)
+        eth_pulse_irq(s);
+
+    /* If c_rx_pingpong was set flip buffers.  */
+    s->rxbuf ^= s->c_rx_pingpong;
+    return;
+}
+
+static void eth_cleanup(VLANClientState *vc)
+{
+    struct xlx_ethlite *s = vc->opaque;
+    qemu_free(s);
+}
+
+static void xilinx_ethlite_init(SysBusDevice *dev)
+{
+    struct xlx_ethlite *s = FROM_SYSBUS(typeof (*s), dev);
+    int regs;
+
+    sysbus_init_irq(dev, &s->irq);
+    s->c_tx_pingpong = qdev_get_prop_int(&dev->qdev, "txpingpong", 1);
+    s->c_rx_pingpong = qdev_get_prop_int(&dev->qdev, "rxpingpong", 1);
+    s->rxbuf = 0;
+
+    regs = cpu_register_io_memory(0, eth_read, eth_write, s);
+    sysbus_init_mmio(dev, R_MAX * 4, regs);
+
+    qdev_get_macaddr(&dev->qdev, s->macaddr);
+    s->vc = qdev_get_vlan_client(&dev->qdev,
+                                 eth_rx, eth_can_rx, eth_cleanup, s);
+}
+
+static void xilinx_ethlite_register(void)
+{
+    sysbus_register_dev("xilinx,ethlite", sizeof (struct xlx_ethlite),
+                        xilinx_ethlite_init);
+}
+
+device_init(xilinx_ethlite_register)