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-rw-r--r--qemu/hw/char/pl011.c342
1 files changed, 342 insertions, 0 deletions
diff --git a/qemu/hw/char/pl011.c b/qemu/hw/char/pl011.c
new file mode 100644
index 000000000..eac6fac09
--- /dev/null
+++ b/qemu/hw/char/pl011.c
@@ -0,0 +1,342 @@
+/*
+ * Arm PrimeCell PL011 UART
+ *
+ * Copyright (c) 2006 CodeSourcery.
+ * Written by Paul Brook
+ *
+ * This code is licensed under the GPL.
+ */
+
+#include "hw/sysbus.h"
+#include "sysemu/char.h"
+
+#define TYPE_PL011 "pl011"
+#define PL011(obj) OBJECT_CHECK(PL011State, (obj), TYPE_PL011)
+
+typedef struct PL011State {
+ SysBusDevice parent_obj;
+
+ MemoryRegion iomem;
+ uint32_t readbuff;
+ uint32_t flags;
+ uint32_t lcr;
+ uint32_t rsr;
+ uint32_t cr;
+ uint32_t dmacr;
+ uint32_t int_enabled;
+ uint32_t int_level;
+ uint32_t read_fifo[16];
+ uint32_t ilpr;
+ uint32_t ibrd;
+ uint32_t fbrd;
+ uint32_t ifl;
+ int read_pos;
+ int read_count;
+ int read_trigger;
+ CharDriverState *chr;
+ qemu_irq irq;
+ const unsigned char *id;
+} PL011State;
+
+#define PL011_INT_TX 0x20
+#define PL011_INT_RX 0x10
+
+#define PL011_FLAG_TXFE 0x80
+#define PL011_FLAG_RXFF 0x40
+#define PL011_FLAG_TXFF 0x20
+#define PL011_FLAG_RXFE 0x10
+
+static const unsigned char pl011_id_arm[8] =
+ { 0x11, 0x10, 0x14, 0x00, 0x0d, 0xf0, 0x05, 0xb1 };
+static const unsigned char pl011_id_luminary[8] =
+ { 0x11, 0x00, 0x18, 0x01, 0x0d, 0xf0, 0x05, 0xb1 };
+
+static void pl011_update(PL011State *s)
+{
+ uint32_t flags;
+
+ flags = s->int_level & s->int_enabled;
+ qemu_set_irq(s->irq, flags != 0);
+}
+
+static uint64_t pl011_read(void *opaque, hwaddr offset,
+ unsigned size)
+{
+ PL011State *s = (PL011State *)opaque;
+ uint32_t c;
+
+ if (offset >= 0xfe0 && offset < 0x1000) {
+ return s->id[(offset - 0xfe0) >> 2];
+ }
+ switch (offset >> 2) {
+ case 0: /* UARTDR */
+ s->flags &= ~PL011_FLAG_RXFF;
+ c = s->read_fifo[s->read_pos];
+ if (s->read_count > 0) {
+ s->read_count--;
+ if (++s->read_pos == 16)
+ s->read_pos = 0;
+ }
+ if (s->read_count == 0) {
+ s->flags |= PL011_FLAG_RXFE;
+ }
+ if (s->read_count == s->read_trigger - 1)
+ s->int_level &= ~ PL011_INT_RX;
+ s->rsr = c >> 8;
+ pl011_update(s);
+ if (s->chr) {
+ qemu_chr_accept_input(s->chr);
+ }
+ return c;
+ case 1: /* UARTRSR */
+ return s->rsr;
+ case 6: /* UARTFR */
+ return s->flags;
+ case 8: /* UARTILPR */
+ return s->ilpr;
+ case 9: /* UARTIBRD */
+ return s->ibrd;
+ case 10: /* UARTFBRD */
+ return s->fbrd;
+ case 11: /* UARTLCR_H */
+ return s->lcr;
+ case 12: /* UARTCR */
+ return s->cr;
+ case 13: /* UARTIFLS */
+ return s->ifl;
+ case 14: /* UARTIMSC */
+ return s->int_enabled;
+ case 15: /* UARTRIS */
+ return s->int_level;
+ case 16: /* UARTMIS */
+ return s->int_level & s->int_enabled;
+ case 18: /* UARTDMACR */
+ return s->dmacr;
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "pl011_read: Bad offset %x\n", (int)offset);
+ return 0;
+ }
+}
+
+static void pl011_set_read_trigger(PL011State *s)
+{
+#if 0
+ /* The docs say the RX interrupt is triggered when the FIFO exceeds
+ the threshold. However linux only reads the FIFO in response to an
+ interrupt. Triggering the interrupt when the FIFO is non-empty seems
+ to make things work. */
+ if (s->lcr & 0x10)
+ s->read_trigger = (s->ifl >> 1) & 0x1c;
+ else
+#endif
+ s->read_trigger = 1;
+}
+
+static void pl011_write(void *opaque, hwaddr offset,
+ uint64_t value, unsigned size)
+{
+ PL011State *s = (PL011State *)opaque;
+ unsigned char ch;
+
+ switch (offset >> 2) {
+ case 0: /* UARTDR */
+ /* ??? Check if transmitter is enabled. */
+ ch = value;
+ if (s->chr)
+ qemu_chr_fe_write(s->chr, &ch, 1);
+ s->int_level |= PL011_INT_TX;
+ pl011_update(s);
+ break;
+ case 1: /* UARTRSR/UARTECR */
+ s->rsr = 0;
+ break;
+ case 6: /* UARTFR */
+ /* Writes to Flag register are ignored. */
+ break;
+ case 8: /* UARTUARTILPR */
+ s->ilpr = value;
+ break;
+ case 9: /* UARTIBRD */
+ s->ibrd = value;
+ break;
+ case 10: /* UARTFBRD */
+ s->fbrd = value;
+ break;
+ case 11: /* UARTLCR_H */
+ /* Reset the FIFO state on FIFO enable or disable */
+ if ((s->lcr ^ value) & 0x10) {
+ s->read_count = 0;
+ s->read_pos = 0;
+ }
+ s->lcr = value;
+ pl011_set_read_trigger(s);
+ break;
+ case 12: /* UARTCR */
+ /* ??? Need to implement the enable and loopback bits. */
+ s->cr = value;
+ break;
+ case 13: /* UARTIFS */
+ s->ifl = value;
+ pl011_set_read_trigger(s);
+ break;
+ case 14: /* UARTIMSC */
+ s->int_enabled = value;
+ pl011_update(s);
+ break;
+ case 17: /* UARTICR */
+ s->int_level &= ~value;
+ pl011_update(s);
+ break;
+ case 18: /* UARTDMACR */
+ s->dmacr = value;
+ if (value & 3) {
+ qemu_log_mask(LOG_UNIMP, "pl011: DMA not implemented\n");
+ }
+ break;
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "pl011_write: Bad offset %x\n", (int)offset);
+ }
+}
+
+static int pl011_can_receive(void *opaque)
+{
+ PL011State *s = (PL011State *)opaque;
+
+ if (s->lcr & 0x10)
+ return s->read_count < 16;
+ else
+ return s->read_count < 1;
+}
+
+static void pl011_put_fifo(void *opaque, uint32_t value)
+{
+ PL011State *s = (PL011State *)opaque;
+ int slot;
+
+ slot = s->read_pos + s->read_count;
+ if (slot >= 16)
+ slot -= 16;
+ s->read_fifo[slot] = value;
+ s->read_count++;
+ s->flags &= ~PL011_FLAG_RXFE;
+ if (!(s->lcr & 0x10) || s->read_count == 16) {
+ s->flags |= PL011_FLAG_RXFF;
+ }
+ if (s->read_count == s->read_trigger) {
+ s->int_level |= PL011_INT_RX;
+ pl011_update(s);
+ }
+}
+
+static void pl011_receive(void *opaque, const uint8_t *buf, int size)
+{
+ pl011_put_fifo(opaque, *buf);
+}
+
+static void pl011_event(void *opaque, int event)
+{
+ if (event == CHR_EVENT_BREAK)
+ pl011_put_fifo(opaque, 0x400);
+}
+
+static const MemoryRegionOps pl011_ops = {
+ .read = pl011_read,
+ .write = pl011_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static const VMStateDescription vmstate_pl011 = {
+ .name = "pl011",
+ .version_id = 2,
+ .minimum_version_id = 2,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32(readbuff, PL011State),
+ VMSTATE_UINT32(flags, PL011State),
+ VMSTATE_UINT32(lcr, PL011State),
+ VMSTATE_UINT32(rsr, PL011State),
+ VMSTATE_UINT32(cr, PL011State),
+ VMSTATE_UINT32(dmacr, PL011State),
+ VMSTATE_UINT32(int_enabled, PL011State),
+ VMSTATE_UINT32(int_level, PL011State),
+ VMSTATE_UINT32_ARRAY(read_fifo, PL011State, 16),
+ VMSTATE_UINT32(ilpr, PL011State),
+ VMSTATE_UINT32(ibrd, PL011State),
+ VMSTATE_UINT32(fbrd, PL011State),
+ VMSTATE_UINT32(ifl, PL011State),
+ VMSTATE_INT32(read_pos, PL011State),
+ VMSTATE_INT32(read_count, PL011State),
+ VMSTATE_INT32(read_trigger, PL011State),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void pl011_init(Object *obj)
+{
+ SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
+ PL011State *s = PL011(obj);
+
+ memory_region_init_io(&s->iomem, OBJECT(s), &pl011_ops, s, "pl011", 0x1000);
+ sysbus_init_mmio(sbd, &s->iomem);
+ sysbus_init_irq(sbd, &s->irq);
+
+ s->read_trigger = 1;
+ s->ifl = 0x12;
+ s->cr = 0x300;
+ s->flags = 0x90;
+
+ s->id = pl011_id_arm;
+}
+
+static void pl011_realize(DeviceState *dev, Error **errp)
+{
+ PL011State *s = PL011(dev);
+
+ /* FIXME use a qdev chardev prop instead of qemu_char_get_next_serial() */
+ s->chr = qemu_char_get_next_serial();
+
+ if (s->chr) {
+ qemu_chr_add_handlers(s->chr, pl011_can_receive, pl011_receive,
+ pl011_event, s);
+ }
+}
+
+static void pl011_class_init(ObjectClass *oc, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(oc);
+
+ dc->realize = pl011_realize;
+ dc->vmsd = &vmstate_pl011;
+ /* Reason: realize() method uses qemu_char_get_next_serial() */
+ dc->cannot_instantiate_with_device_add_yet = true;
+}
+
+static const TypeInfo pl011_arm_info = {
+ .name = TYPE_PL011,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(PL011State),
+ .instance_init = pl011_init,
+ .class_init = pl011_class_init,
+};
+
+static void pl011_luminary_init(Object *obj)
+{
+ PL011State *s = PL011(obj);
+
+ s->id = pl011_id_luminary;
+}
+
+static const TypeInfo pl011_luminary_info = {
+ .name = "pl011_luminary",
+ .parent = TYPE_PL011,
+ .instance_init = pl011_luminary_init,
+};
+
+static void pl011_register_types(void)
+{
+ type_register_static(&pl011_arm_info);
+ type_register_static(&pl011_luminary_info);
+}
+
+type_init(pl011_register_types)