NIC emulation for qemu arm-softmmu (Paul Brook)

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1682 c046a42c-6fe2-441c-8c8c-71466251a162

1 files changed, 680 insertions, 0 deletions

diff --git a/hw/smc91c111.c b/hw/smc91c111.c
new file mode 100644
index 0000000..54433c4
--- /dev/null
+++ b/hw/smc91c111.c
@@ -0,0 +1,680 @@
+/* 
+ * SMSC 91C111 Ethernet interface emulation
+ *
+ * Copyright (c) 2005 CodeSourcery, LLC.
+ * Written by Paul Brook
+ *
+ * This code is licenced under the GPL
+ */
+
+#include "vl.h"
+/* For crc32 */
+#include <zlib.h>
+
+/* Number of 2k memory pages available.  */
+#define NUM_PACKETS 4
+
+typedef struct {
+    uint32_t base;
+    VLANClientState *vc;
+    uint16_t tcr;
+    uint16_t rcr;
+    uint16_t cr;
+    uint16_t ctr;
+    uint16_t gpr;
+    uint16_t ptr;
+    uint16_t ercv;
+    void *pic;
+    int irq;
+    int bank;
+    int packet_num;
+    int tx_alloc;
+    /* Bitmask of allocated packets.  */
+    int allocated;
+    int tx_fifo_len;
+    int tx_fifo[NUM_PACKETS];
+    int rx_fifo_len;
+    int rx_fifo[NUM_PACKETS];
+    /* Packet buffer memory.  */
+    uint8_t data[2048][NUM_PACKETS];
+    uint8_t int_level;
+    uint8_t int_mask;
+    uint8_t macaddr[6];
+} smc91c111_state;
+
+#define RCR_SOFT_RST  0x8000
+#define RCR_STRIP_CRC 0x0200
+#define RCR_RXEN      0x0100
+
+#define TCR_EPH_LOOP  0x2000
+#define TCR_NOCRC     0x0100
+#define TCR_PAD_EN    0x0080
+#define TCR_FORCOL    0x0004
+#define TCR_LOOP      0x0002
+#define TCR_TXEN      0x0001
+
+#define INT_MD        0x80
+#define INT_ERCV      0x40
+#define INT_EPH       0x20
+#define INT_RX_OVRN   0x10
+#define INT_ALLOC     0x08
+#define INT_TX_EMPTY  0x04
+#define INT_TX        0x02
+#define INT_RCV       0x01
+
+#define CTR_AUTO_RELEASE  0x0800
+#define CTR_RELOAD        0x0002
+#define CTR_STORE         0x0001
+
+#define RS_ALGNERR      0x8000
+#define RS_BRODCAST     0x4000
+#define RS_BADCRC       0x2000
+#define RS_ODDFRAME     0x1000
+#define RS_TOOLONG      0x0800
+#define RS_TOOSHORT     0x0400
+#define RS_MULTICAST    0x0001
+
+/* Update interrupt status.  */
+static void smc91c111_update(smc91c111_state *s)
+{
+    int level;
+
+    if (s->tx_fifo_len == 0)
+        s->int_level |= INT_TX_EMPTY;
+    level = (s->int_level & s->int_mask) != 0;
+    pic_set_irq_new(s->pic, s->irq, level);
+}
+
+/* Try to allocate a packet.  Returns 0x80 on failure.  */
+static int smc91c111_allocate_packet(smc91c111_state *s)
+{
+    int i;
+    if (s->allocated == (1 << NUM_PACKETS) - 1) {
+        return 0x80;
+    }
+
+    for (i = 0; i < NUM_PACKETS; i++) {
+        if ((s->allocated & (1 << i)) == 0)
+            break;
+    }
+    s->allocated |= 1 << i;
+    return i;
+}
+
+
+/* Process a pending TX allocate.  */
+static void smc91c111_tx_alloc(smc91c111_state *s)
+{
+    s->tx_alloc = smc91c111_allocate_packet(s);
+    if (s->tx_alloc == 0x80)
+        return;
+    s->int_level |= INT_ALLOC;
+    smc91c111_update(s);
+}
+
+/* Remove and item from the RX FIFO.  */
+static void smc91c111_pop_rx_fifo(smc91c111_state *s)
+{
+    int i;
+
+    s->rx_fifo_len--;
+    if (s->rx_fifo_len) {
+        for (i = 0; i < s->rx_fifo_len; i++)
+            s->rx_fifo[i] = s->rx_fifo[i + 1];
+        s->int_level |= INT_RCV;
+    } else {
+        s->int_level &= ~INT_RCV;
+    }
+    smc91c111_update(s);
+}
+
+/* Release the memory allocated to a packet.  */
+static void smc91c111_release_packet(smc91c111_state *s, int packet)
+{
+    s->allocated &= ~(1 << packet);
+    if (s->tx_alloc == 0x80)
+        smc91c111_tx_alloc(s);
+}
+
+/* Flush the TX FIFO.  */
+static void smc91c111_do_tx(smc91c111_state *s)
+{
+    int i;
+    int len;
+    int control;
+    int add_crc;
+    uint32_t crc;
+    int packetnum;
+    uint8_t *p;
+
+    if ((s->tcr & TCR_TXEN) == 0)
+        return;
+    if (s->tx_fifo_len == 0)
+        return;
+    for (i = 0; i < s->tx_fifo_len; i++) {
+        packetnum = s->tx_fifo[i];
+        p = &s->data[packetnum][0];
+        /* Set status word.  */
+        *(p++) = 0x01;
+        *(p++) = 0x40;
+        len = *(p++);
+        len |= ((int)*(p++)) << 8;
+        len -= 6;
+        control = p[len + 1];
+        if (control & 0x20)
+            len++;
+        /* ??? This overwrites the data following the buffer.
+           Don't know what real hardware does.  */
+        if (len < 64 && (s->tcr & TCR_PAD_EN)) {
+            memset(p + len, 0, 64 - len);
+            len = 64;
+        }
+#if 0
+        /* The card is supposed to append the CRC to the frame.  However
+           none of the other network traffic has the CRC appended.
+           Suspect this is low level ethernet detail we don't need to worry
+           about.  */
+        add_crc = (control & 0x10) || (s->tcr & TCR_NOCRC) == 0;
+        if (add_crc) {
+            crc = crc32(~0, p, len);
+            memcpy(p + len, &crc, 4);
+            len += 4;
+        }
+#else
+        add_crc = 0;
+#endif
+        if (s->ctr & CTR_AUTO_RELEASE)
+            smc91c111_release_packet(s, packetnum);
+        qemu_send_packet(s->vc, p, len);
+    }
+    s->tx_fifo_len = 0;
+    if ((s->ctr & CTR_AUTO_RELEASE) == 0)
+        s->int_level |= INT_TX;
+    smc91c111_update(s);
+}
+
+/* Add a packet to the TX FIFO.  */
+static void smc91c111_queue_tx(smc91c111_state *s, int packet)
+{
+    if (s->tx_fifo_len == NUM_PACKETS)
+        return;
+    s->tx_fifo[s->tx_fifo_len++] = packet;
+    smc91c111_do_tx(s);
+}
+
+static void smc91c111_reset(smc91c111_state *s)
+{
+    s->bank = 0;
+    s->tx_fifo_len = 0;
+    s->rx_fifo_len = 0;
+    s->allocated = 0;
+    s->packet_num = 0;
+    s->tx_alloc = 0;
+    s->tcr = 0;
+    s->rcr = 0;
+    s->cr = 0xa0b1;
+    s->ctr = 0x1210;
+    s->ptr = 0;
+    s->ercv = 0x1f;
+    s->int_level = INT_TX_EMPTY;
+    s->int_mask = 0;
+    smc91c111_update(s);
+}
+
+#define SET_LOW(name, val) s->name = (s->name & 0xff00) | val
+#define SET_HIGH(name, val) s->name = (s->name & 0xff) | (val << 8)
+
+static void smc91c111_writeb(void *opaque, target_phys_addr_t offset,
+                             uint32_t value)
+{
+    smc91c111_state *s = (smc91c111_state *)opaque;
+
+    offset -= s->base;
+    if (offset == 14) {
+        s->bank = value;
+        return;
+    }
+    if (offset == 15)
+        return;
+    switch (s->bank) {
+    case 0:
+        switch (offset) {
+        case 0: /* TCR */
+            SET_LOW(tcr, value);
+            return;
+        case 1:
+            SET_HIGH(tcr, value);
+            return;
+        case 4: /* RCR */
+            SET_LOW(rcr, value);
+            return;
+        case 5:
+            SET_HIGH(rcr, value);
+            if (s->rcr & RCR_SOFT_RST)
+                smc91c111_reset(s);
+            return;
+        case 10: case 11: /* RPCR */
+            /* Ignored */
+            return;
+        }
+        break;
+
+    case 1:
+        switch (offset) {
+        case 0: /* CONFIG */
+            SET_LOW(cr, value);
+            return;
+        case 1:
+            SET_HIGH(cr,value);
+            return;
+        case 2: case 3: /* BASE */
+        case 4: case 5: case 6: case 7: case 8: case 9: /* IA */
+            /* Not implemented.  */
+            return;
+        case 10: /* Genral Purpose */
+            SET_LOW(gpr, value);
+            return;
+        case 11:
+            SET_HIGH(gpr, value);
+            return;
+        case 12: /* Control */
+            if (value & 1)
+                fprintf(stderr, "smc91c111:EEPROM store not implemented\n");
+            if (value & 2)
+                fprintf(stderr, "smc91c111:EEPROM reload not implemented\n");
+            value &= ~3;
+            SET_LOW(ctr, value);
+            return;
+        case 13:
+            SET_HIGH(ctr, value);
+            return;
+        }
+        break;
+
+    case 2:
+        switch (offset) {
+        case 0: /* MMU Command */
+            switch (value >> 5) {
+            case 0: /* no-op */
+                break;
+            case 1: /* Allocate for TX.  */
+                s->tx_alloc = 0x80;
+                s->int_level &= ~INT_ALLOC;
+                smc91c111_update(s);
+                smc91c111_tx_alloc(s);
+                break;
+            case 2: /* Reset MMU.  */
+                s->allocated = 0;
+                s->tx_fifo_len = 0;
+                s->rx_fifo_len = 0;
+                s->tx_alloc = 0;
+                break;
+            case 3: /* Remove from RX FIFO.  */
+                smc91c111_pop_rx_fifo(s);
+                break;
+            case 4: /* Remove from RX FIFO and release.  */
+                if (s->rx_fifo_len > 0) {
+                    smc91c111_release_packet(s, s->rx_fifo[0]);
+                }
+                smc91c111_pop_rx_fifo(s);
+                break;
+            case 5: /* Release.  */
+                smc91c111_release_packet(s, s->packet_num);
+                break;
+            case 6: /* Add to TX FIFO.  */
+                smc91c111_queue_tx(s, s->packet_num);
+                break;
+            case 7: /* Reset TX FIFO.  */
+                s->tx_fifo_len = 0;
+                break;
+            }
+            return;
+        case 1:
+            /* Ignore.  */
+            return;
+        case 2: /* Packet Number Register */
+            s->packet_num = value;
+            return;
+        case 3: case 4: case 5:
+            /* Should be readonly, but linux writes to them anyway. Ignore.  */
+            return;
+        case 6: /* Pointer */
+            SET_LOW(ptr, value);
+            return;
+        case 7:
+            SET_HIGH(ptr, value);
+            return;
+        case 8: case 9: case 10: case 11: /* Data */
+            {
+                int p;
+                int n;
+
+                if (s->ptr & 0x8000)
+                    n = s->rx_fifo[0];
+                else
+                    n = s->packet_num;
+                p = s->ptr & 0x07ff;
+                if (s->ptr & 0x4000) {
+                    s->ptr = (s->ptr & 0xf800) | ((s->ptr + 1) & 0x7ff);
+                } else {
+                    p += (offset & 3);
+                }
+                s->data[n][p] = value;
+            }
+            return;
+        case 12: /* Interrupt ACK.  */
+            s->int_level &= ~(value & 0xd6);
+            smc91c111_update(s);
+            return;
+        case 13: /* Interrupt mask.  */
+            s->int_mask = value;
+            smc91c111_update(s);
+            return;
+        }
+        break;;
+
+    case 3:
+        switch (offset) {
+        case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
+            /* Multicast table.  */
+            /* Not implemented.  */
+            return;
+        case 8: case 9: /* Management Interface.  */
+            /* Not implemented.  */
+            return;
+        case 12: /* Early receive.  */
+            s->ercv = value & 0x1f;
+        case 13:
+            /* Ignore.  */
+            return;
+        }
+        break;
+    }
+    cpu_abort (cpu_single_env, "smc91c111_write: Bad reg %d:%x\n",
+               s->bank, offset);
+}
+
+static uint32_t smc91c111_readb(void *opaque, target_phys_addr_t offset)
+{
+    smc91c111_state *s = (smc91c111_state *)opaque;
+
+    offset -= s->base;
+    if (offset == 14) {
+        return s->bank;
+    }
+    if (offset == 15)
+        return 0x33;
+    switch (s->bank) {
+    case 0:
+        switch (offset) {
+        case 0: /* TCR */
+            return s->tcr & 0xff;
+        case 1:
+            return s->tcr >> 8;
+        case 2: /* EPH Status */
+            return 0;
+        case 3:
+            return 0x40;
+        case 4: /* RCR */
+            return s->rcr & 0xff;
+        case 5:
+            return s->rcr >> 8;
+        case 6: /* Counter */
+        case 7:
+            /* Not implemented.  */
+            return 0;
+        case 8: /* Free memory available.  */
+            {
+                int i;
+                int n;
+                n = 0;
+                for (i = 0; i < NUM_PACKETS; i++) {
+                    if (s->allocated & (1 << i))
+                        n++;
+                }
+                return n;
+            }
+        case 9: /* Memory size.  */
+            return NUM_PACKETS;
+        case 10: case 11: /* RPCR */
+            /* Not implemented.  */
+            return 0;
+        }
+        break;
+
+    case 1:
+        switch (offset) {
+        case 0: /* CONFIG */
+            return s->cr & 0xff;
+        case 1:
+            return s->cr >> 8;
+        case 2: case 3: /* BASE */
+            /* Not implemented.  */
+            return 0;
+        case 4: case 5: case 6: case 7: case 8: case 9: /* IA */
+            return s->macaddr[offset - 4];
+        case 10: /* General Purpose */
+            return s->gpr & 0xff;
+        case 11:
+            return s->gpr >> 8;
+        case 12: /* Control */
+            return s->ctr & 0xff;
+        case 13:
+            return s->ctr >> 8;
+        }
+        break;
+
+    case 2:
+        switch (offset) {
+        case 0: case 1: /* MMUCR Busy bit.  */
+            return 0;
+        case 2: /* Packet Number.  */
+            return s->packet_num;
+        case 3: /* Allocation Result.  */
+            return s->tx_alloc;
+        case 4: /* TX FIFO */
+            if (s->tx_fifo_len == 0)
+                return 0x80;
+            else
+                return s->tx_fifo[0];
+        case 5: /* RX FIFO */
+            if (s->rx_fifo_len == 0)
+                return 0x80;
+            else
+                return s->rx_fifo[0];
+        case 6: /* Pointer */
+            return s->ptr & 0xff;
+        case 7:
+            return (s->ptr >> 8) & 0xf7;
+        case 8: case 9: case 10: case 11: /* Data */
+            {
+                int p;
+                int n;
+
+                if (s->ptr & 0x8000)
+                    n = s->rx_fifo[0];
+                else
+                    n = s->packet_num;
+                p = s->ptr & 0x07ff;
+                if (s->ptr & 0x4000) {
+                    s->ptr = (s->ptr & 0xf800) | ((s->ptr + 1) & 0x07ff);
+                } else {
+                    p += (offset & 3);
+                }
+                return s->data[n][p];
+            }
+        case 12: /* Interrupt status.  */
+            return s->int_level;
+        case 13: /* Interrupt mask.  */
+            return s->int_mask;
+        }
+        break;
+
+    case 3:
+        switch (offset) {
+        case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
+            /* Multicast table.  */
+            /* Not implemented.  */
+            return 0;
+        case 8: /* Management Interface.  */
+            /* Not implemented.  */
+            return 0x30;
+        case 9:
+            return 0x33;
+        case 10: /* Revision.  */
+            return 0x91;
+        case 11:
+            return 0x33;
+        case 12:
+            return s->ercv;
+        case 13:
+            return 0;
+        }
+        break;
+    }
+    cpu_abort (cpu_single_env, "smc91c111_read: Bad reg %d:%x\n",
+               s->bank, offset);
+    return 0;
+}
+
+static void smc91c111_writew(void *opaque, target_phys_addr_t offset,
+                             uint32_t value)
+{
+    smc91c111_writeb(opaque, offset, value & 0xff);
+    smc91c111_writeb(opaque, offset + 1, value >> 8);
+}
+
+static void smc91c111_writel(void *opaque, target_phys_addr_t offset,
+                             uint32_t value)
+{
+    smc91c111_state *s = (smc91c111_state *)opaque;
+    /* 32-bit writes to offset 0xc only actually write to the bank select
+       register (offset 0xe)  */
+    if (offset != s->base + 0xc)
+        smc91c111_writew(opaque, offset, value & 0xffff);
+    smc91c111_writew(opaque, offset + 2, value >> 16);
+}
+
+static uint32_t smc91c111_readw(void *opaque, target_phys_addr_t offset)
+{
+    uint32_t val;
+    val = smc91c111_readb(opaque, offset);
+    val |= smc91c111_readb(opaque, offset + 1) << 8;
+    return val;
+}
+
+static uint32_t smc91c111_readl(void *opaque, target_phys_addr_t offset)
+{
+    uint32_t val;
+    val = smc91c111_readw(opaque, offset);
+    val |= smc91c111_readw(opaque, offset + 2) << 16;
+    return val;
+}
+
+static void smc91c111_receive(void *opaque, const uint8_t *buf, int size)
+{
+    smc91c111_state *s = (smc91c111_state *)opaque;
+    int status;
+    int packetsize;
+    uint32_t crc;
+    int packetnum;
+    uint8_t *p;
+
+    if ((s->rcr & RCR_RXEN) == 0 || (s->rcr & RCR_SOFT_RST))
+        return;
+    /* Short packets are padded with zeros.  Recieveing a packet
+       < 64 bytes long is considered an error condition.  */
+    if (size < 64)
+        packetsize = 64;
+    else
+        packetsize = (size & ~1);
+    packetsize += 6;
+    crc = (s->rcr & RCR_STRIP_CRC) == 0;
+    if (crc)
+        packetsize += 4;
+    /* TODO: Flag overrun and receive errors.  */
+    if (packetsize > 2048)
+        return;
+    packetnum = smc91c111_allocate_packet(s);
+    if (packetnum == 0x80)
+        return;
+    s->rx_fifo[s->rx_fifo_len++] = packetnum;
+
+    p = &s->data[packetnum][0];
+    /* ??? Multicast packets?  */
+    status = 0;
+    if (size > 1518)
+        status |= RS_TOOLONG;
+    if (size & 1)
+        status |= RS_ODDFRAME;
+    *(p++) = status & 0xff;
+    *(p++) = status >> 8;
+    *(p++) = packetsize & 0xff;
+    *(p++) = packetsize >> 8;
+    memcpy(p, buf, size & ~1);
+    p += (size & ~1);
+    /* Pad short packets.  */
+    if (size < 64) {
+        int pad;
+        
+        if (size & 1)
+            *(p++) = buf[size - 1];
+        pad = 64 - size;
+        memset(p, 0, pad);
+        p += pad;
+        size = 64;
+    }
+    /* It's not clear if the CRC should go before or after the last byte in
+       odd sized packets.  Linux disables the CRC, so that's no help.
+       The pictures in the documentation show the CRC aligned on a 16-bit
+       boundary before the last odd byte, so that's what we do.  */
+    if (crc) {
+        crc = crc32(~0, buf, size);
+        *(p++) = crc & 0xff; crc >>= 8;
+        *(p++) = crc & 0xff; crc >>= 8;
+        *(p++) = crc & 0xff; crc >>= 8;
+        *(p++) = crc & 0xff; crc >>= 8;
+    }
+    if (size & 1) {
+        *(p++) = buf[size - 1];
+        *(p++) = 0x60;
+    } else {
+        *(p++) = 0;
+        *(p++) = 0x40;
+    }
+    /* TODO: Raise early RX interrupt?  */
+    s->int_level |= INT_RCV;
+    smc91c111_update(s);
+}
+
+static CPUReadMemoryFunc *smc91c111_readfn[] = {
+    smc91c111_readb,
+    smc91c111_readw,
+    smc91c111_readl
+};
+
+static CPUWriteMemoryFunc *smc91c111_writefn[] = {
+    smc91c111_writeb,
+    smc91c111_writew,
+    smc91c111_writel
+};
+
+void smc91c111_init(NICInfo *nd, uint32_t base, void *pic, int irq)
+{
+    smc91c111_state *s;
+    int iomemtype;
+
+    s = (smc91c111_state *)qemu_mallocz(sizeof(smc91c111_state));
+    iomemtype = cpu_register_io_memory(0, smc91c111_readfn,
+                                       smc91c111_writefn, s);
+    cpu_register_physical_memory(base, 16, iomemtype);
+    s->base = base;
+    s->pic = pic;
+    s->irq = irq;
+    memcpy(s->macaddr, nd->macaddr, 6);
+
+    smc91c111_reset(s);
+
+    s->vc = qemu_new_vlan_client(nd->vlan, smc91c111_receive, s);
+    /* ??? Save/restore.  */
+}