symbian-qemu-0.9.1-12/qemu-symbian-svp/hw/pl022.c
changeset 1 2fb8b9db1c86
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/qemu-symbian-svp/hw/pl022.c	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,308 @@
+/*
+ * Arm PrimeCell PL022 Synchronous Serial Port
+ *
+ * Copyright (c) 2007 CodeSourcery.
+ * Written by Paul Brook
+ *
+ * This code is licenced under the GPL.
+ */
+
+#include "hw.h"
+#include "primecell.h"
+
+//#define DEBUG_PL022 1
+
+#ifdef DEBUG_PL022
+#define DPRINTF(fmt, args...) \
+do { printf("pl022: " fmt , ##args); } while (0)
+#define BADF(fmt, args...) \
+do { fprintf(stderr, "pl022: error: " fmt , ##args); exit(1);} while (0)
+#else
+#define DPRINTF(fmt, args...) do {} while(0)
+#define BADF(fmt, args...) \
+do { fprintf(stderr, "pl022: error: " fmt , ##args);} while (0)
+#endif
+
+#define PL022_CR1_LBM 0x01
+#define PL022_CR1_SSE 0x02
+#define PL022_CR1_MS  0x04
+#define PL022_CR1_SDO 0x08
+
+#define PL022_SR_TFE  0x01
+#define PL022_SR_TNF  0x02
+#define PL022_SR_RNE  0x04
+#define PL022_SR_RFF  0x08
+#define PL022_SR_BSY  0x10
+
+#define PL022_INT_ROR 0x01
+#define PL022_INT_RT  0x04
+#define PL022_INT_RX  0x04
+#define PL022_INT_TX  0x08
+
+typedef struct {
+    uint32_t cr0;
+    uint32_t cr1;
+    uint32_t bitmask;
+    uint32_t sr;
+    uint32_t cpsr;
+    uint32_t is;
+    uint32_t im;
+    /* The FIFO head points to the next empty entry.  */
+    int tx_fifo_head;
+    int rx_fifo_head;
+    int tx_fifo_len;
+    int rx_fifo_len;
+    uint16_t tx_fifo[8];
+    uint16_t rx_fifo[8];
+    qemu_irq irq;
+    int (*xfer_cb)(void *, int);
+    void *opaque;
+} pl022_state;
+
+static const unsigned char pl022_id[8] =
+  { 0x22, 0x10, 0x04, 0x00, 0x0d, 0xf0, 0x05, 0xb1 };
+
+static void pl022_update(pl022_state *s)
+{
+    s->sr = 0;
+    if (s->tx_fifo_len == 0)
+        s->sr |= PL022_SR_TFE;
+    if (s->tx_fifo_len != 8)
+        s->sr |= PL022_SR_TNF;
+    if (s->rx_fifo_len != 0)
+        s->sr |= PL022_SR_RNE;
+    if (s->rx_fifo_len == 8)
+        s->sr |= PL022_SR_RFF;
+    if (s->tx_fifo_len)
+        s->sr |= PL022_SR_BSY;
+    s->is = 0;
+    if (s->rx_fifo_len >= 4)
+        s->is |= PL022_INT_RX;
+    if (s->tx_fifo_len <= 4)
+        s->is |= PL022_INT_TX;
+
+    qemu_set_irq(s->irq, (s->is & s->im) != 0);
+}
+
+static void pl022_xfer(pl022_state *s)
+{
+    int i;
+    int o;
+    int val;
+
+    if ((s->cr1 & PL022_CR1_SSE) == 0) {
+        pl022_update(s);
+        DPRINTF("Disabled\n");
+        return;
+    }
+
+    DPRINTF("Maybe xfer %d/%d\n", s->tx_fifo_len, s->rx_fifo_len);
+    i = (s->tx_fifo_head - s->tx_fifo_len) & 7;
+    o = s->rx_fifo_head;
+    /* ??? We do not emulate the line speed.
+       This may break some applications.  The are two problematic cases:
+        (a) A driver feeds data into the TX FIFO until it is full,
+         and only then drains the RX FIFO.  On real hardware the CPU can
+         feed data fast enough that the RX fifo never gets chance to overflow.
+        (b) A driver transmits data, deliberately allowing the RX FIFO to
+         overflow because it ignores the RX data anyway.
+
+       We choose to support (a) by stalling the transmit engine if it would
+       cause the RX FIFO to overflow.  In practice much transmit-only code
+       falls into (a) because it flushes the RX FIFO to determine when
+       the transfer has completed.  */
+    while (s->tx_fifo_len && s->rx_fifo_len < 8) {
+        DPRINTF("xfer\n");
+        val = s->tx_fifo[i];
+        if (s->cr1 & PL022_CR1_LBM) {
+            /* Loopback mode.  */
+        } else if (s->xfer_cb) {
+            val = s->xfer_cb(s->opaque, val);
+        } else {
+            val = 0;
+        }
+        s->rx_fifo[o] = val & s->bitmask;
+        i = (i + 1) & 7;
+        o = (o + 1) & 7;
+        s->tx_fifo_len--;
+        s->rx_fifo_len++;
+    }
+    s->rx_fifo_head = o;
+    pl022_update(s);
+}
+
+static uint32_t pl022_read(void *opaque, target_phys_addr_t offset)
+{
+    pl022_state *s = (pl022_state *)opaque;
+    int val;
+
+    if (offset >= 0xfe0 && offset < 0x1000) {
+        return pl022_id[(offset - 0xfe0) >> 2];
+    }
+    switch (offset) {
+    case 0x00: /* CR0 */
+      return s->cr0;
+    case 0x04: /* CR1 */
+      return s->cr1;
+    case 0x08: /* DR */
+        if (s->rx_fifo_len) {
+            val = s->rx_fifo[(s->rx_fifo_head - s->rx_fifo_len) & 7];
+            DPRINTF("RX %02x\n", val);
+            s->rx_fifo_len--;
+            pl022_xfer(s);
+        } else {
+            val = 0;
+        }
+        return val;
+    case 0x0c: /* SR */
+        return s->sr;
+    case 0x10: /* CPSR */
+        return s->cpsr;
+    case 0x14: /* IMSC */
+        return s->im;
+    case 0x18: /* RIS */
+        return s->is;
+    case 0x1c: /* MIS */
+        return s->im & s->is;
+    case 0x20: /* DMACR */
+        /* Not implemented.  */
+        return 0;
+    default:
+        cpu_abort (cpu_single_env, "pl022_read: Bad offset %x\n",
+                   (int)offset);
+        return 0;
+    }
+}
+
+static void pl022_write(void *opaque, target_phys_addr_t offset,
+                        uint32_t value)
+{
+    pl022_state *s = (pl022_state *)opaque;
+
+    switch (offset) {
+    case 0x00: /* CR0 */
+        s->cr0 = value;
+        /* Clock rate and format are ignored.  */
+        s->bitmask = (1 << ((value & 15) + 1)) - 1;
+        break;
+    case 0x04: /* CR1 */
+        s->cr1 = value;
+        if ((s->cr1 & (PL022_CR1_MS | PL022_CR1_SSE))
+                   == (PL022_CR1_MS | PL022_CR1_SSE)) {
+            BADF("SPI slave mode not implemented\n");
+        }
+        pl022_xfer(s);
+        break;
+    case 0x08: /* DR */
+        if (s->tx_fifo_len < 8) {
+            DPRINTF("TX %02x\n", value);
+            s->tx_fifo[s->tx_fifo_head] = value & s->bitmask;
+            s->tx_fifo_head = (s->tx_fifo_head + 1) & 7;
+            s->tx_fifo_len++;
+            pl022_xfer(s);
+        }
+        break;
+    case 0x10: /* CPSR */
+        /* Prescaler.  Ignored.  */
+        s->cpsr = value & 0xff;
+        break;
+    case 0x14: /* IMSC */
+        s->im = value;
+        pl022_update(s);
+        break;
+    case 0x20: /* DMACR */
+        if (value)
+            cpu_abort (cpu_single_env, "pl022: DMA not implemented\n");
+        break;
+    default:
+        cpu_abort (cpu_single_env, "pl022_write: Bad offset %x\n",
+                   (int)offset);
+    }
+}
+
+static void pl022_reset(pl022_state *s)
+{
+    s->rx_fifo_len = 0;
+    s->tx_fifo_len = 0;
+    s->im = 0;
+    s->is = PL022_INT_TX;
+    s->sr = PL022_SR_TFE | PL022_SR_TNF;
+}
+
+static CPUReadMemoryFunc *pl022_readfn[] = {
+   pl022_read,
+   pl022_read,
+   pl022_read
+};
+
+static CPUWriteMemoryFunc *pl022_writefn[] = {
+   pl022_write,
+   pl022_write,
+   pl022_write
+};
+
+static void pl022_save(QEMUFile *f, void *opaque)
+{
+    pl022_state *s = (pl022_state *)opaque;
+    int i;
+
+    qemu_put_be32(f, s->cr0);
+    qemu_put_be32(f, s->cr1);
+    qemu_put_be32(f, s->bitmask);
+    qemu_put_be32(f, s->sr);
+    qemu_put_be32(f, s->cpsr);
+    qemu_put_be32(f, s->is);
+    qemu_put_be32(f, s->im);
+    qemu_put_be32(f, s->tx_fifo_head);
+    qemu_put_be32(f, s->rx_fifo_head);
+    qemu_put_be32(f, s->tx_fifo_len);
+    qemu_put_be32(f, s->rx_fifo_len);
+    for (i = 0; i < 8; i++) {
+        qemu_put_be16(f, s->tx_fifo[i]);
+        qemu_put_be16(f, s->rx_fifo[i]);
+    }
+}
+
+static int pl022_load(QEMUFile *f, void *opaque, int version_id)
+{
+    pl022_state *s = (pl022_state *)opaque;
+    int i;
+
+    if (version_id != 1)
+        return -EINVAL;
+
+    s->cr0 = qemu_get_be32(f);
+    s->cr1 = qemu_get_be32(f);
+    s->bitmask = qemu_get_be32(f);
+    s->sr = qemu_get_be32(f);
+    s->cpsr = qemu_get_be32(f);
+    s->is = qemu_get_be32(f);
+    s->im = qemu_get_be32(f);
+    s->tx_fifo_head = qemu_get_be32(f);
+    s->rx_fifo_head = qemu_get_be32(f);
+    s->tx_fifo_len = qemu_get_be32(f);
+    s->rx_fifo_len = qemu_get_be32(f);
+    for (i = 0; i < 8; i++) {
+        s->tx_fifo[i] = qemu_get_be16(f);
+        s->rx_fifo[i] = qemu_get_be16(f);
+    }
+
+    return 0;
+}
+
+void pl022_init(uint32_t base, qemu_irq irq, int (*xfer_cb)(void *, int),
+                void * opaque)
+{
+    int iomemtype;
+    pl022_state *s;
+
+    s = (pl022_state *)qemu_mallocz(sizeof(pl022_state));
+    iomemtype = cpu_register_io_memory(0, pl022_readfn,
+                                       pl022_writefn, s);
+    cpu_register_physical_memory(base, 0x00001000, iomemtype);
+    s->irq = irq;
+    s->xfer_cb = xfer_cb;
+    s->opaque = opaque;
+    pl022_reset(s);
+    register_savevm("pl022_ssp", -1, 1, pl022_save, pl022_load, s);
+}