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-rw-r--r--src/hw/misc/zynq-xadc.c302
1 files changed, 302 insertions, 0 deletions
diff --git a/src/hw/misc/zynq-xadc.c b/src/hw/misc/zynq-xadc.c
new file mode 100644
index 0000000..1a32595
--- /dev/null
+++ b/src/hw/misc/zynq-xadc.c
@@ -0,0 +1,302 @@
+/*
+ * ADC registers for Xilinx Zynq Platform
+ *
+ * Copyright (c) 2015 Guenter Roeck
+ * Based on hw/misc/zynq_slcr.c, written by Michal Simek
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "hw/hw.h"
+#include "hw/misc/zynq-xadc.h"
+#include "qemu/timer.h"
+#include "sysemu/sysemu.h"
+
+enum {
+ CFG = 0x000 / 4,
+ INT_STS,
+ INT_MASK,
+ MSTS,
+ CMDFIFO,
+ RDFIFO,
+ MCTL,
+};
+
+#define CFG_ENABLE BIT(31)
+#define CFG_CFIFOTH_SHIFT 20
+#define CFG_CFIFOTH_LENGTH 4
+#define CFG_DFIFOTH_SHIFT 16
+#define CFG_DFIFOTH_LENGTH 4
+#define CFG_WEDGE BIT(13)
+#define CFG_REDGE BIT(12)
+#define CFG_TCKRATE_SHIFT 8
+#define CFG_TCKRATE_LENGTH 2
+
+#define CFG_TCKRATE_DIV(x) (0x1 << (x - 1))
+
+#define CFG_IGAP_SHIFT 0
+#define CFG_IGAP_LENGTH 5
+
+#define INT_CFIFO_LTH BIT(9)
+#define INT_DFIFO_GTH BIT(8)
+#define INT_OT BIT(7)
+#define INT_ALM_SHIFT 0
+#define INT_ALM_LENGTH 7
+#define INT_ALM_MASK (((1 << INT_ALM_LENGTH) - 1) << INT_ALM_SHIFT)
+
+#define INT_ALL (INT_CFIFO_LTH | INT_DFIFO_GTH | INT_OT | INT_ALM_MASK)
+
+#define MSTS_CFIFO_LVL_SHIFT 16
+#define MSTS_CFIFO_LVL_LENGTH 4
+#define MSTS_DFIFO_LVL_SHIFT 12
+#define MSTS_DFIFO_LVL_LENGTH 4
+#define MSTS_CFIFOF BIT(11)
+#define MSTS_CFIFOE BIT(10)
+#define MSTS_DFIFOF BIT(9)
+#define MSTS_DFIFOE BIT(8)
+#define MSTS_OT BIT(7)
+#define MSTS_ALM_SHIFT 0
+#define MSTS_ALM_LENGTH 7
+
+#define MCTL_RESET BIT(4)
+
+#define CMD_NOP 0x00
+#define CMD_READ 0x01
+#define CMD_WRITE 0x02
+
+static void zynq_xadc_update_ints(ZynqXADCState *s)
+{
+
+ /* We are fast, commands are actioned instantly so the CFIFO is always
+ * empty (and below threshold).
+ */
+ s->regs[INT_STS] |= INT_CFIFO_LTH;
+
+ if (s->xadc_dfifo_entries >
+ extract32(s->regs[CFG], CFG_DFIFOTH_SHIFT, CFG_DFIFOTH_LENGTH)) {
+ s->regs[INT_STS] |= INT_DFIFO_GTH;
+ }
+
+ qemu_set_irq(s->qemu_irq, !!(s->regs[INT_STS] & ~s->regs[INT_MASK]));
+}
+
+static void zynq_xadc_reset(DeviceState *d)
+{
+ ZynqXADCState *s = ZYNQ_XADC(d);
+
+ s->regs[CFG] = 0x14 << CFG_IGAP_SHIFT |
+ CFG_TCKRATE_DIV(4) << CFG_TCKRATE_SHIFT | CFG_REDGE;
+ s->regs[INT_STS] = INT_CFIFO_LTH;
+ s->regs[INT_MASK] = 0xffffffff;
+ s->regs[CMDFIFO] = 0;
+ s->regs[RDFIFO] = 0;
+ s->regs[MCTL] = MCTL_RESET;
+
+ memset(s->xadc_regs, 0, sizeof(s->xadc_regs));
+ memset(s->xadc_dfifo, 0, sizeof(s->xadc_dfifo));
+ s->xadc_dfifo_entries = 0;
+
+ zynq_xadc_update_ints(s);
+}
+
+static uint16_t xadc_pop_dfifo(ZynqXADCState *s)
+{
+ uint16_t rv = s->xadc_dfifo[0];
+ int i;
+
+ if (s->xadc_dfifo_entries > 0) {
+ s->xadc_dfifo_entries--;
+ }
+ for (i = 0; i < s->xadc_dfifo_entries; i++) {
+ s->xadc_dfifo[i] = s->xadc_dfifo[i + 1];
+ }
+ s->xadc_dfifo[s->xadc_dfifo_entries] = 0;
+ zynq_xadc_update_ints(s);
+ return rv;
+}
+
+static void xadc_push_dfifo(ZynqXADCState *s, uint16_t regval)
+{
+ if (s->xadc_dfifo_entries < ZYNQ_XADC_FIFO_DEPTH) {
+ s->xadc_dfifo[s->xadc_dfifo_entries++] = s->xadc_read_reg_previous;
+ }
+ s->xadc_read_reg_previous = regval;
+ zynq_xadc_update_ints(s);
+}
+
+static bool zynq_xadc_check_offset(hwaddr offset, bool rnw)
+{
+ switch (offset) {
+ case CFG:
+ case INT_MASK:
+ case INT_STS:
+ case MCTL:
+ return true;
+ case RDFIFO:
+ case MSTS:
+ return rnw; /* read only */
+ case CMDFIFO:
+ return !rnw; /* write only */
+ default:
+ return false;
+ }
+}
+
+static uint64_t zynq_xadc_read(void *opaque, hwaddr offset, unsigned size)
+{
+ ZynqXADCState *s = opaque;
+ int reg = offset / 4;
+ uint32_t rv = 0;
+
+ if (!zynq_xadc_check_offset(reg, true)) {
+ qemu_log_mask(LOG_GUEST_ERROR, "zynq_xadc: Invalid read access to "
+ "addr %" HWADDR_PRIx "\n", offset);
+ return 0;
+ }
+
+ switch (reg) {
+ case CFG:
+ case INT_MASK:
+ case INT_STS:
+ case MCTL:
+ rv = s->regs[reg];
+ break;
+ case MSTS:
+ rv = MSTS_CFIFOE;
+ rv |= s->xadc_dfifo_entries << MSTS_DFIFO_LVL_SHIFT;
+ if (!s->xadc_dfifo_entries) {
+ rv |= MSTS_DFIFOE;
+ } else if (s->xadc_dfifo_entries == ZYNQ_XADC_FIFO_DEPTH) {
+ rv |= MSTS_DFIFOF;
+ }
+ break;
+ case RDFIFO:
+ rv = xadc_pop_dfifo(s);
+ break;
+ }
+ return rv;
+}
+
+static void zynq_xadc_write(void *opaque, hwaddr offset, uint64_t val,
+ unsigned size)
+{
+ ZynqXADCState *s = (ZynqXADCState *)opaque;
+ int reg = offset / 4;
+ int xadc_reg;
+ int xadc_cmd;
+ int xadc_data;
+
+ if (!zynq_xadc_check_offset(reg, false)) {
+ qemu_log_mask(LOG_GUEST_ERROR, "zynq_xadc: Invalid write access "
+ "to addr %" HWADDR_PRIx "\n", offset);
+ return;
+ }
+
+ switch (reg) {
+ case CFG:
+ s->regs[CFG] = val;
+ break;
+ case INT_STS:
+ s->regs[INT_STS] &= ~val;
+ break;
+ case INT_MASK:
+ s->regs[INT_MASK] = val & INT_ALL;
+ break;
+ case CMDFIFO:
+ xadc_cmd = extract32(val, 26, 4);
+ xadc_reg = extract32(val, 16, 10);
+ xadc_data = extract32(val, 0, 16);
+
+ if (s->regs[MCTL] & MCTL_RESET) {
+ qemu_log_mask(LOG_GUEST_ERROR, "zynq_xadc: Sending command "
+ "while comm channel held in reset: %" PRIx32 "\n",
+ (uint32_t) val);
+ break;
+ }
+
+ if (xadc_reg > ZYNQ_XADC_NUM_ADC_REGS && xadc_cmd != CMD_NOP) {
+ qemu_log_mask(LOG_GUEST_ERROR, "read/write op to invalid xadc "
+ "reg 0x%x\n", xadc_reg);
+ break;
+ }
+
+ switch (xadc_cmd) {
+ case CMD_READ:
+ xadc_push_dfifo(s, s->xadc_regs[xadc_reg]);
+ break;
+ case CMD_WRITE:
+ s->xadc_regs[xadc_reg] = xadc_data;
+ /* fallthrough */
+ case CMD_NOP:
+ xadc_push_dfifo(s, 0);
+ break;
+ }
+ break;
+ case MCTL:
+ s->regs[MCTL] = val & 0x00fffeff;
+ break;
+ }
+ zynq_xadc_update_ints(s);
+}
+
+static const MemoryRegionOps xadc_ops = {
+ .read = zynq_xadc_read,
+ .write = zynq_xadc_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static void zynq_xadc_init(Object *obj)
+{
+ SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
+ ZynqXADCState *s = ZYNQ_XADC(obj);
+
+ memory_region_init_io(&s->iomem, obj, &xadc_ops, s, "zynq-xadc",
+ ZYNQ_XADC_MMIO_SIZE);
+ sysbus_init_mmio(sbd, &s->iomem);
+ sysbus_init_irq(sbd, &s->qemu_irq);
+}
+
+static const VMStateDescription vmstate_zynq_xadc = {
+ .name = "zynq-xadc",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32_ARRAY(regs, ZynqXADCState, ZYNQ_XADC_NUM_IO_REGS),
+ VMSTATE_UINT16_ARRAY(xadc_regs, ZynqXADCState,
+ ZYNQ_XADC_NUM_ADC_REGS),
+ VMSTATE_UINT16_ARRAY(xadc_dfifo, ZynqXADCState,
+ ZYNQ_XADC_FIFO_DEPTH),
+ VMSTATE_UINT16(xadc_read_reg_previous, ZynqXADCState),
+ VMSTATE_UINT16(xadc_dfifo_entries, ZynqXADCState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void zynq_xadc_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->vmsd = &vmstate_zynq_xadc;
+ dc->reset = zynq_xadc_reset;
+}
+
+static const TypeInfo zynq_xadc_info = {
+ .class_init = zynq_xadc_class_init,
+ .name = TYPE_ZYNQ_XADC,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(ZynqXADCState),
+ .instance_init = zynq_xadc_init,
+};
+
+static void zynq_xadc_register_types(void)
+{
+ type_register_static(&zynq_xadc_info);
+}
+
+type_init(zynq_xadc_register_types)
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