xilinx: Add AXIENET & DMA models

Signed-off-by: Edgar E. Iglesias <edgar.iglesias@petalogix.com>

1 files changed, 509 insertions, 0 deletions

diff --git a/hw/xilinx_axidma.c b/hw/xilinx_axidma.c
new file mode 100644
index 0000000..e32534f
--- /dev/null
+++ b/hw/xilinx_axidma.c
@@ -0,0 +1,509 @@
+/*
+ * QEMU model of Xilinx AXI-DMA block.
+ *
+ * Copyright (c) 2011 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 "qemu-char.h"
+#include "qemu-timer.h"
+#include "qemu-log.h"
+#include "qdev-addr.h"
+
+#include "xilinx_axidma.h"
+
+#define D(x)
+
+#define R_DMACR             (0x00 / 4)
+#define R_DMASR             (0x04 / 4)
+#define R_CURDESC           (0x08 / 4)
+#define R_TAILDESC          (0x10 / 4)
+#define R_MAX               (0x30 / 4)
+
+enum {
+    DMACR_RUNSTOP = 1,
+    DMACR_TAILPTR_MODE = 2,
+    DMACR_RESET = 4
+};
+
+enum {
+    DMASR_HALTED = 1,
+    DMASR_IDLE  = 2,
+    DMASR_IOC_IRQ  = 1 << 12,
+    DMASR_DLY_IRQ  = 1 << 13,
+
+    DMASR_IRQ_MASK = 7 << 12
+};
+
+struct SDesc {
+    uint64_t nxtdesc;
+    uint64_t buffer_address;
+    uint64_t reserved;
+    uint32_t control;
+    uint32_t status;
+    uint32_t app[6];
+};
+
+enum {
+    SDESC_CTRL_EOF = (1 << 26),
+    SDESC_CTRL_SOF = (1 << 27),
+
+    SDESC_CTRL_LEN_MASK = (1 << 23) - 1
+};
+
+enum {
+    SDESC_STATUS_EOF = (1 << 26),
+    SDESC_STATUS_SOF_BIT = 27,
+    SDESC_STATUS_SOF = (1 << SDESC_STATUS_SOF_BIT),
+    SDESC_STATUS_COMPLETE = (1 << 31)
+};
+
+struct AXIStream {
+    QEMUBH *bh;
+    ptimer_state *ptimer;
+    qemu_irq irq;
+
+    int nr;
+
+    struct SDesc desc;
+    int pos;
+    unsigned int complete_cnt;
+    uint32_t regs[R_MAX];
+};
+
+struct XilinxAXIDMA {
+    SysBusDevice busdev;
+    uint32_t freqhz;
+    void *dmach;
+
+    struct AXIStream streams[2];
+};
+
+/*
+ * Helper calls to extract info from desriptors and other trivial
+ * state from regs.
+ */
+static inline int stream_desc_sof(struct SDesc *d)
+{
+    return d->control & SDESC_CTRL_SOF;
+}
+
+static inline int stream_desc_eof(struct SDesc *d)
+{
+    return d->control & SDESC_CTRL_EOF;
+}
+
+static inline int stream_resetting(struct AXIStream *s)
+{
+    return !!(s->regs[R_DMACR] & DMACR_RESET);
+}
+
+static inline int stream_running(struct AXIStream *s)
+{
+    return s->regs[R_DMACR] & DMACR_RUNSTOP;
+}
+
+static inline int stream_halted(struct AXIStream *s)
+{
+    return s->regs[R_DMASR] & DMASR_HALTED;
+}
+
+static inline int stream_idle(struct AXIStream *s)
+{
+    return !!(s->regs[R_DMASR] & DMASR_IDLE);
+}
+
+static void stream_reset(struct AXIStream *s)
+{
+    s->regs[R_DMASR] = DMASR_HALTED;  /* starts up halted.  */
+    s->regs[R_DMACR] = 1 << 16; /* Starts with one in compl threshhold.  */
+}
+
+/* Mapp an offset addr into a channel index.  */
+static inline int streamid_from_addr(target_phys_addr_t addr)
+{
+    int sid;
+
+    sid = addr / (0x30);
+    sid &= 1;
+    return sid;
+}
+
+#ifdef DEBUG_ENET
+static void stream_desc_show(struct SDesc *d)
+{
+    qemu_log("buffer_addr  = " PRIx64 "\n", d->buffer_address);
+    qemu_log("nxtdesc      = " PRIx64 "\n", d->nxtdesc);
+    qemu_log("control      = %x\n", d->control);
+    qemu_log("status       = %x\n", d->status);
+}
+#endif
+
+static void stream_desc_load(struct AXIStream *s, target_phys_addr_t addr)
+{
+    struct SDesc *d = &s->desc;
+    int i;
+
+    cpu_physical_memory_read(addr, (void *) d, sizeof *d);
+
+    /* Convert from LE into host endianness.  */
+    d->buffer_address = le64_to_cpu(d->buffer_address);
+    d->nxtdesc = le64_to_cpu(d->nxtdesc);
+    d->control = le32_to_cpu(d->control);
+    d->status = le32_to_cpu(d->status);
+    for (i = 0; i < ARRAY_SIZE(d->app); i++) {
+        d->app[i] = le32_to_cpu(d->app[i]);
+    }
+}
+
+static void stream_desc_store(struct AXIStream *s, target_phys_addr_t addr)
+{
+    struct SDesc *d = &s->desc;
+    int i;
+
+    /* Convert from host endianness into LE.  */
+    d->buffer_address = cpu_to_le64(d->buffer_address);
+    d->nxtdesc = cpu_to_le64(d->nxtdesc);
+    d->control = cpu_to_le32(d->control);
+    d->status = cpu_to_le32(d->status);
+    for (i = 0; i < ARRAY_SIZE(d->app); i++) {
+        d->app[i] = cpu_to_le32(d->app[i]);
+    }
+    cpu_physical_memory_write(addr, (void *) d, sizeof *d);
+}
+
+static void stream_update_irq(struct AXIStream *s)
+{
+    unsigned int pending, mask, irq;
+
+    pending = s->regs[R_DMASR] & DMASR_IRQ_MASK;
+    mask = s->regs[R_DMACR] & DMASR_IRQ_MASK;
+
+    irq = pending & mask;
+
+    qemu_set_irq(s->irq, !!irq);
+}
+
+static void stream_reload_complete_cnt(struct AXIStream *s)
+{
+    unsigned int comp_th;
+    comp_th = (s->regs[R_DMACR] >> 16) & 0xff;
+    s->complete_cnt = comp_th;
+}
+
+static void timer_hit(void *opaque)
+{
+    struct AXIStream *s = opaque;
+
+    stream_reload_complete_cnt(s);
+    s->regs[R_DMASR] |= DMASR_DLY_IRQ;
+    stream_update_irq(s);
+}
+
+static void stream_complete(struct AXIStream *s)
+{
+    unsigned int comp_delay;
+
+    /* Start the delayed timer.  */
+    comp_delay = s->regs[R_DMACR] >> 24;
+    if (comp_delay) {
+        ptimer_stop(s->ptimer);
+        ptimer_set_count(s->ptimer, comp_delay);
+        ptimer_run(s->ptimer, 1);
+    }
+
+    s->complete_cnt--;
+    if (s->complete_cnt == 0) {
+        /* Raise the IOC irq.  */
+        s->regs[R_DMASR] |= DMASR_IOC_IRQ;
+        stream_reload_complete_cnt(s);
+    }
+}
+
+static void stream_process_mem2s(struct AXIStream *s,
+                                 struct XilinxDMAConnection *dmach)
+{
+    uint32_t prev_d;
+    unsigned char txbuf[16 * 1024];
+    unsigned int txlen;
+    uint32_t app[6];
+
+    if (!stream_running(s) || stream_idle(s)) {
+        return;
+    }
+
+    while (1) {
+        stream_desc_load(s, s->regs[R_CURDESC]);
+
+        if (s->desc.status & SDESC_STATUS_COMPLETE) {
+            s->regs[R_DMASR] |= DMASR_IDLE;
+            break;
+        }
+
+        if (stream_desc_sof(&s->desc)) {
+            s->pos = 0;
+            memcpy(app, s->desc.app, sizeof app);
+        }
+
+        txlen = s->desc.control & SDESC_CTRL_LEN_MASK;
+        if ((txlen + s->pos) > sizeof txbuf) {
+            hw_error("%s: too small internal txbuf! %d\n", __func__,
+                     txlen + s->pos);
+        }
+
+        cpu_physical_memory_read(s->desc.buffer_address,
+                                 txbuf + s->pos, txlen);
+        s->pos += txlen;
+
+        if (stream_desc_eof(&s->desc)) {
+            xlx_dma_push_to_client(dmach, txbuf, s->pos, app);
+            s->pos = 0;
+            stream_complete(s);
+        }
+
+        /* Update the descriptor.  */
+        s->desc.status = txlen | SDESC_STATUS_COMPLETE;
+        stream_desc_store(s, s->regs[R_CURDESC]);
+
+        /* Advance.  */
+        prev_d = s->regs[R_CURDESC];
+        s->regs[R_CURDESC] = s->desc.nxtdesc;
+        if (prev_d == s->regs[R_TAILDESC]) {
+            s->regs[R_DMASR] |= DMASR_IDLE;
+            break;
+        }
+    }
+}
+
+static void stream_process_s2mem(struct AXIStream *s,
+                                 unsigned char *buf, size_t len, uint32_t *app)
+{
+    uint32_t prev_d;
+    unsigned int rxlen;
+    int pos = 0;
+    int sof = 1;
+
+    if (!stream_running(s) || stream_idle(s)) {
+        return;
+    }
+
+    while (len) {
+        stream_desc_load(s, s->regs[R_CURDESC]);
+
+        if (s->desc.status & SDESC_STATUS_COMPLETE) {
+            s->regs[R_DMASR] |= DMASR_IDLE;
+            break;
+        }
+
+        rxlen = s->desc.control & SDESC_CTRL_LEN_MASK;
+        if (rxlen > len) {
+            /* It fits.  */
+            rxlen = len;
+        }
+
+        cpu_physical_memory_write(s->desc.buffer_address, buf + pos, rxlen);
+        len -= rxlen;
+        pos += rxlen;
+
+        /* Update the descriptor.  */
+        if (!len) {
+            int i;
+
+            stream_complete(s);
+            for (i = 0; i < 5; i++) {
+                s->desc.app[i] = app[i];
+            }
+            s->desc.status |= SDESC_STATUS_EOF;
+        }
+
+        s->desc.status |= sof << SDESC_STATUS_SOF_BIT;
+        s->desc.status |= SDESC_STATUS_COMPLETE;
+        stream_desc_store(s, s->regs[R_CURDESC]);
+        sof = 0;
+
+        /* Advance.  */
+        prev_d = s->regs[R_CURDESC];
+        s->regs[R_CURDESC] = s->desc.nxtdesc;
+        if (prev_d == s->regs[R_TAILDESC]) {
+            s->regs[R_DMASR] |= DMASR_IDLE;
+            break;
+        }
+    }
+}
+
+static
+void axidma_push(void *opaque, unsigned char *buf, size_t len, uint32_t *app)
+{
+    struct XilinxAXIDMA *d = opaque;
+    struct AXIStream *s = &d->streams[1];
+
+    if (!app) {
+        hw_error("No stream app data!\n");
+    }
+    stream_process_s2mem(s, buf, len, app);
+    stream_update_irq(s);
+}
+
+static uint32_t axidma_readl(void *opaque, target_phys_addr_t addr)
+{
+    struct XilinxAXIDMA *d = opaque;
+    struct AXIStream *s;
+    uint32_t r = 0;
+    int sid;
+
+    sid = streamid_from_addr(addr);
+    s = &d->streams[sid];
+
+    addr = addr % 0x30;
+    addr >>= 2;
+    switch (addr) {
+        case R_DMACR:
+            /* Simulate one cycles reset delay.  */
+            s->regs[addr] &= ~DMACR_RESET;
+            r = s->regs[addr];
+            break;
+        case R_DMASR:
+            s->regs[addr] &= 0xffff;
+            s->regs[addr] |= (s->complete_cnt & 0xff) << 16;
+            s->regs[addr] |= (ptimer_get_count(s->ptimer) & 0xff) << 24;
+            r = s->regs[addr];
+            break;
+        default:
+            r = s->regs[addr];
+            D(qemu_log("%s ch=%d addr=" TARGET_FMT_plx " v=%x\n",
+                           __func__, sid, addr * 4, r));
+            break;
+    }
+    return r;
+
+}
+
+static void
+axidma_writel(void *opaque, target_phys_addr_t addr, uint32_t value)
+{
+    struct XilinxAXIDMA *d = opaque;
+    struct AXIStream *s;
+    int sid;
+
+    sid = streamid_from_addr(addr);
+    s = &d->streams[sid];
+
+    addr = addr % 0x30;
+    addr >>= 2;
+    switch (addr) {
+        case R_DMACR:
+            /* Tailptr mode is always on.  */
+            value |= DMACR_TAILPTR_MODE;
+            /* Remember our previous reset state.  */
+            value |= (s->regs[addr] & DMACR_RESET);
+            s->regs[addr] = value;
+
+            if (value & DMACR_RESET) {
+                stream_reset(s);
+            }
+
+            if ((value & 1) && !stream_resetting(s)) {
+                /* Start processing.  */
+                s->regs[R_DMASR] &= ~(DMASR_HALTED | DMASR_IDLE);
+            }
+            stream_reload_complete_cnt(s);
+            break;
+
+        case R_DMASR:
+            /* Mask away write to clear irq lines.  */
+            value &= ~(value & DMASR_IRQ_MASK);
+            s->regs[addr] = value;
+            break;
+
+        case R_TAILDESC:
+            s->regs[addr] = value;
+            s->regs[R_DMASR] &= ~DMASR_IDLE; /* Not idle.  */
+            if (!sid) {
+                stream_process_mem2s(s, d->dmach);
+            }
+            break;
+        default:
+            D(qemu_log("%s: ch=%d addr=" TARGET_FMT_plx " v=%x\n",
+                  __func__, sid, addr * 4, value));
+            s->regs[addr] = value;
+            break;
+    }
+    stream_update_irq(s);
+}
+
+static CPUReadMemoryFunc * const axidma_read[] = {
+    &axidma_readl,
+    &axidma_readl,
+    &axidma_readl,
+};
+
+static CPUWriteMemoryFunc * const axidma_write[] = {
+    &axidma_writel,
+    &axidma_writel,
+    &axidma_writel,
+};
+
+static int xilinx_axidma_init(SysBusDevice *dev)
+{
+    struct XilinxAXIDMA *s = FROM_SYSBUS(typeof(*s), dev);
+    int axidma_regs;
+    int i;
+
+    sysbus_init_irq(dev, &s->streams[1].irq);
+    sysbus_init_irq(dev, &s->streams[0].irq);
+
+    if (!s->dmach) {
+        hw_error("Unconnected DMA channel.\n");
+    }
+
+    xlx_dma_connect_dma(s->dmach, s, axidma_push);
+
+    axidma_regs = cpu_register_io_memory(axidma_read, axidma_write, s,
+                                       DEVICE_NATIVE_ENDIAN);
+    sysbus_init_mmio(dev, R_MAX * 4 * 2, axidma_regs);
+
+    for (i = 0; i < 2; i++) {
+        stream_reset(&s->streams[i]);
+        s->streams[i].nr = i;
+        s->streams[i].bh = qemu_bh_new(timer_hit, &s->streams[i]);
+        s->streams[i].ptimer = ptimer_init(s->streams[i].bh);
+        ptimer_set_freq(s->streams[i].ptimer, s->freqhz);
+    }
+    return 0;
+}
+
+static SysBusDeviceInfo axidma_info = {
+    .init = xilinx_axidma_init,
+    .qdev.name  = "xilinx,axidma",
+    .qdev.size  = sizeof(struct XilinxAXIDMA),
+    .qdev.props = (Property[]) {
+        DEFINE_PROP_UINT32("freqhz", struct XilinxAXIDMA, freqhz, 50000000),
+        DEFINE_PROP_PTR("dmach", struct XilinxAXIDMA, dmach),
+        DEFINE_PROP_END_OF_LIST(),
+    }
+};
+
+static void xilinx_axidma_register(void)
+{
+    sysbus_register_withprop(&axidma_info);
+}
+
+device_init(xilinx_axidma_register)