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authorSteffen Görtz <contrib@steffen-goertz.de>2019-01-07 15:23:47 +0000
committerPeter Maydell <peter.maydell@linaro.org>2019-01-07 15:23:47 +0000
commit805f61bbb33ba24777a854df5d018858502d6d9c (patch)
treebf3c08ff53cc0fbb95df31def69b02ce599dab72
parentf30890def51f777db1da350f9c737cc75615bdf0 (diff)
downloadqemu-arm-805f61bbb33ba24777a854df5d018858502d6d9c.tar.gz
hw/gpio/nrf51_gpio: Add nRF51 GPIO peripheral
This adds a model of the nRF51 GPIO peripheral. Reference Manual: http://infocenter.nordicsemi.com/pdf/nRF51_RM_v3.0.pdf The nRF51 series microcontrollers support up to 32 GPIO pins in various configurations. The pins can be used as input pins with pull-ups or pull-down. Furthermore, three different output driver modes per level are available (disconnected, standard, high-current). The GPIO-Peripheral has a mechanism for detecting level changes which is not featured in this model. Signed-off-by: Steffen Görtz <contrib@steffen-goertz.de> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20190103091119.9367-6-stefanha@redhat.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
-rw-r--r--Makefile.objs1
-rw-r--r--hw/gpio/Makefile.objs1
-rw-r--r--hw/gpio/nrf51_gpio.c300
-rw-r--r--hw/gpio/trace-events7
-rw-r--r--include/hw/gpio/nrf51_gpio.h69
5 files changed, 378 insertions, 0 deletions
diff --git a/Makefile.objs b/Makefile.objs
index bc5b8a8442..456115992a 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -184,6 +184,7 @@ trace-events-subdirs += hw/vfio
trace-events-subdirs += hw/virtio
trace-events-subdirs += hw/watchdog
trace-events-subdirs += hw/xen
+trace-events-subdirs += hw/gpio
trace-events-subdirs += io
trace-events-subdirs += linux-user
trace-events-subdirs += migration
diff --git a/hw/gpio/Makefile.objs b/hw/gpio/Makefile.objs
index fa0a72e6d0..e5da0cb54f 100644
--- a/hw/gpio/Makefile.objs
+++ b/hw/gpio/Makefile.objs
@@ -8,3 +8,4 @@ common-obj-$(CONFIG_GPIO_KEY) += gpio_key.o
obj-$(CONFIG_OMAP) += omap_gpio.o
obj-$(CONFIG_IMX) += imx_gpio.o
obj-$(CONFIG_RASPI) += bcm2835_gpio.o
+obj-$(CONFIG_NRF51_SOC) += nrf51_gpio.o
diff --git a/hw/gpio/nrf51_gpio.c b/hw/gpio/nrf51_gpio.c
new file mode 100644
index 0000000000..86e047d649
--- /dev/null
+++ b/hw/gpio/nrf51_gpio.c
@@ -0,0 +1,300 @@
+/*
+ * nRF51 System-on-Chip general purpose input/output register definition
+ *
+ * Reference Manual: http://infocenter.nordicsemi.com/pdf/nRF51_RM_v3.0.pdf
+ * Product Spec: http://infocenter.nordicsemi.com/pdf/nRF51822_PS_v3.1.pdf
+ *
+ * Copyright 2018 Steffen Görtz <contrib@steffen-goertz.de>
+ *
+ * This code is licensed under the GPL version 2 or later. See
+ * the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "hw/gpio/nrf51_gpio.h"
+#include "trace.h"
+
+/*
+ * Check if the output driver is connected to the direction switch
+ * given the current configuration and logic level.
+ * It is not differentiated between standard and "high"(-power) drive modes.
+ */
+static bool is_connected(uint32_t config, uint32_t level)
+{
+ bool state;
+ uint32_t drive_config = extract32(config, 8, 3);
+
+ switch (drive_config) {
+ case 0 ... 3:
+ state = true;
+ break;
+ case 4 ... 5:
+ state = level != 0;
+ break;
+ case 6 ... 7:
+ state = level == 0;
+ break;
+ default:
+ g_assert_not_reached();
+ break;
+ }
+
+ return state;
+}
+
+static void update_output_irq(NRF51GPIOState *s, size_t i,
+ bool connected, bool level)
+{
+ int64_t irq_level = connected ? level : -1;
+ bool old_connected = extract32(s->old_out_connected, i, 1);
+ bool old_level = extract32(s->old_out, i, 1);
+
+ if ((old_connected != connected) || (old_level != level)) {
+ qemu_set_irq(s->output[i], irq_level);
+ trace_nrf51_gpio_update_output_irq(i, irq_level);
+ }
+
+ s->old_out = deposit32(s->old_out, i, 1, level);
+ s->old_out_connected = deposit32(s->old_out_connected, i, 1, connected);
+}
+
+static void update_state(NRF51GPIOState *s)
+{
+ uint32_t pull;
+ size_t i;
+ bool connected_out, dir, connected_in, out, input;
+
+ for (i = 0; i < NRF51_GPIO_PINS; i++) {
+ pull = extract32(s->cnf[i], 2, 2);
+ dir = extract32(s->cnf[i], 0, 1);
+ connected_in = extract32(s->in_mask, i, 1);
+ out = extract32(s->out, i, 1);
+ input = !extract32(s->cnf[i], 1, 1);
+ connected_out = is_connected(s->cnf[i], out) && dir;
+
+ update_output_irq(s, i, connected_out, out);
+
+ /* Pin both driven externally and internally */
+ if (connected_out && connected_in) {
+ qemu_log_mask(LOG_GUEST_ERROR, "GPIO pin %zu short circuited\n", i);
+ }
+
+ /*
+ * Input buffer disconnected from internal/external drives, so
+ * pull-up/pull-down becomes relevant
+ */
+ if (!input || (input && !connected_in && !connected_out)) {
+ if (pull == NRF51_GPIO_PULLDOWN) {
+ s->in = deposit32(s->in, i, 1, 0);
+ } else if (pull == NRF51_GPIO_PULLUP) {
+ s->in = deposit32(s->in, i, 1, 1);
+ }
+ }
+
+ /* Self stimulation through internal output driver */
+ if (connected_out && !connected_in && input) {
+ s->in = deposit32(s->in, i, 1, out);
+ }
+ }
+
+}
+
+/*
+ * Direction is exposed in both the DIR register and the DIR bit
+ * of each PINs CNF configuration register. Reflect bits for pins in DIR
+ * to individual pin configuration registers.
+ */
+static void reflect_dir_bit_in_cnf(NRF51GPIOState *s)
+{
+ size_t i;
+
+ uint32_t value = s->dir;
+
+ for (i = 0; i < NRF51_GPIO_PINS; i++) {
+ s->cnf[i] = (s->cnf[i] & ~(1UL)) | ((value >> i) & 0x01);
+ }
+}
+
+static uint64_t nrf51_gpio_read(void *opaque, hwaddr offset, unsigned int size)
+{
+ NRF51GPIOState *s = NRF51_GPIO(opaque);
+ uint64_t r = 0;
+ size_t idx;
+
+ switch (offset) {
+ case NRF51_GPIO_REG_OUT ... NRF51_GPIO_REG_OUTCLR:
+ r = s->out;
+ break;
+
+ case NRF51_GPIO_REG_IN:
+ r = s->in;
+ break;
+
+ case NRF51_GPIO_REG_DIR ... NRF51_GPIO_REG_DIRCLR:
+ r = s->dir;
+ break;
+
+ case NRF51_GPIO_REG_CNF_START ... NRF51_GPIO_REG_CNF_END:
+ idx = (offset - NRF51_GPIO_REG_CNF_START) / 4;
+ r = s->cnf[idx];
+ break;
+
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "%s: bad read offset 0x%" HWADDR_PRIx "\n",
+ __func__, offset);
+ }
+
+ trace_nrf51_gpio_read(offset, r);
+
+ return r;
+}
+
+static void nrf51_gpio_write(void *opaque, hwaddr offset,
+ uint64_t value, unsigned int size)
+{
+ NRF51GPIOState *s = NRF51_GPIO(opaque);
+ size_t idx;
+
+ trace_nrf51_gpio_write(offset, value);
+
+ switch (offset) {
+ case NRF51_GPIO_REG_OUT:
+ s->out = value;
+ break;
+
+ case NRF51_GPIO_REG_OUTSET:
+ s->out |= value;
+ break;
+
+ case NRF51_GPIO_REG_OUTCLR:
+ s->out &= ~value;
+ break;
+
+ case NRF51_GPIO_REG_DIR:
+ s->dir = value;
+ reflect_dir_bit_in_cnf(s);
+ break;
+
+ case NRF51_GPIO_REG_DIRSET:
+ s->dir |= value;
+ reflect_dir_bit_in_cnf(s);
+ break;
+
+ case NRF51_GPIO_REG_DIRCLR:
+ s->dir &= ~value;
+ reflect_dir_bit_in_cnf(s);
+ break;
+
+ case NRF51_GPIO_REG_CNF_START ... NRF51_GPIO_REG_CNF_END:
+ idx = (offset - NRF51_GPIO_REG_CNF_START) / 4;
+ s->cnf[idx] = value;
+ /*
+ * direction is exposed in both the DIR register and the DIR bit
+ * of each PINs CNF configuration register.
+ */
+ s->dir = (s->dir & ~(1UL << idx)) | ((value & 0x01) << idx);
+ break;
+
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "%s: bad write offset 0x%" HWADDR_PRIx "\n",
+ __func__, offset);
+ }
+
+ update_state(s);
+}
+
+static const MemoryRegionOps gpio_ops = {
+ .read = nrf51_gpio_read,
+ .write = nrf51_gpio_write,
+ .endianness = DEVICE_LITTLE_ENDIAN,
+ .impl.min_access_size = 4,
+ .impl.max_access_size = 4,
+};
+
+static void nrf51_gpio_set(void *opaque, int line, int value)
+{
+ NRF51GPIOState *s = NRF51_GPIO(opaque);
+
+ trace_nrf51_gpio_set(line, value);
+
+ assert(line >= 0 && line < NRF51_GPIO_PINS);
+
+ s->in_mask = deposit32(s->in_mask, line, 1, value >= 0);
+ if (value >= 0) {
+ s->in = deposit32(s->in, line, 1, value != 0);
+ }
+
+ update_state(s);
+}
+
+static void nrf51_gpio_reset(DeviceState *dev)
+{
+ NRF51GPIOState *s = NRF51_GPIO(dev);
+ size_t i;
+
+ s->out = 0;
+ s->old_out = 0;
+ s->old_out_connected = 0;
+ s->in = 0;
+ s->in_mask = 0;
+ s->dir = 0;
+
+ for (i = 0; i < NRF51_GPIO_PINS; i++) {
+ s->cnf[i] = 0x00000002;
+ }
+}
+
+static const VMStateDescription vmstate_nrf51_gpio = {
+ .name = TYPE_NRF51_GPIO,
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32(out, NRF51GPIOState),
+ VMSTATE_UINT32(in, NRF51GPIOState),
+ VMSTATE_UINT32(in_mask, NRF51GPIOState),
+ VMSTATE_UINT32(dir, NRF51GPIOState),
+ VMSTATE_UINT32_ARRAY(cnf, NRF51GPIOState, NRF51_GPIO_PINS),
+ VMSTATE_UINT32(old_out, NRF51GPIOState),
+ VMSTATE_UINT32(old_out_connected, NRF51GPIOState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void nrf51_gpio_init(Object *obj)
+{
+ NRF51GPIOState *s = NRF51_GPIO(obj);
+
+ memory_region_init_io(&s->mmio, obj, &gpio_ops, s,
+ TYPE_NRF51_GPIO, NRF51_GPIO_SIZE);
+ sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
+
+ qdev_init_gpio_in(DEVICE(s), nrf51_gpio_set, NRF51_GPIO_PINS);
+ qdev_init_gpio_out(DEVICE(s), s->output, NRF51_GPIO_PINS);
+}
+
+static void nrf51_gpio_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->vmsd = &vmstate_nrf51_gpio;
+ dc->reset = nrf51_gpio_reset;
+ dc->desc = "nRF51 GPIO";
+}
+
+static const TypeInfo nrf51_gpio_info = {
+ .name = TYPE_NRF51_GPIO,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(NRF51GPIOState),
+ .instance_init = nrf51_gpio_init,
+ .class_init = nrf51_gpio_class_init
+};
+
+static void nrf51_gpio_register_types(void)
+{
+ type_register_static(&nrf51_gpio_info);
+}
+
+type_init(nrf51_gpio_register_types)
diff --git a/hw/gpio/trace-events b/hw/gpio/trace-events
new file mode 100644
index 0000000000..cb41a89756
--- /dev/null
+++ b/hw/gpio/trace-events
@@ -0,0 +1,7 @@
+# See docs/devel/tracing.txt for syntax documentation.
+
+# hw/gpio/nrf51_gpio.c
+nrf51_gpio_read(uint64_t offset, uint64_t r) "offset 0x%" PRIx64 " value 0x%" PRIx64
+nrf51_gpio_write(uint64_t offset, uint64_t value) "offset 0x%" PRIx64 " value 0x%" PRIx64
+nrf51_gpio_set(int64_t line, int64_t value) "line %" PRIi64 " value %" PRIi64
+nrf51_gpio_update_output_irq(int64_t line, int64_t value) "line %" PRIi64 " value %" PRIi64 \ No newline at end of file
diff --git a/include/hw/gpio/nrf51_gpio.h b/include/hw/gpio/nrf51_gpio.h
new file mode 100644
index 0000000000..337ee534bb
--- /dev/null
+++ b/include/hw/gpio/nrf51_gpio.h
@@ -0,0 +1,69 @@
+/*
+ * nRF51 System-on-Chip general purpose input/output register definition
+ *
+ * QEMU interface:
+ * + sysbus MMIO regions 0: GPIO registers
+ * + Unnamed GPIO inputs 0-31: Set tri-state input level for GPIO pin.
+ * Level -1: Externally Disconnected/Floating; Pull-up/down will be regarded
+ * Level 0: Input externally driven LOW
+ * Level 1: Input externally driven HIGH
+ * + Unnamed GPIO outputs 0-31:
+ * Level -1: Disconnected/Floating
+ * Level 0: Driven LOW
+ * Level 1: Driven HIGH
+ *
+ * Accuracy of the peripheral model:
+ * + The nRF51 GPIO output driver supports two modes, standard and high-current
+ * mode. These different drive modes are not modeled and handled the same.
+ * + Pin SENSEing is not modeled/implemented.
+ *
+ * Copyright 2018 Steffen Görtz <contrib@steffen-goertz.de>
+ *
+ * This code is licensed under the GPL version 2 or later. See
+ * the COPYING file in the top-level directory.
+ *
+ */
+#ifndef NRF51_GPIO_H
+#define NRF51_GPIO_H
+
+#include "hw/sysbus.h"
+#define TYPE_NRF51_GPIO "nrf51_soc.gpio"
+#define NRF51_GPIO(obj) OBJECT_CHECK(NRF51GPIOState, (obj), TYPE_NRF51_GPIO)
+
+#define NRF51_GPIO_PINS 32
+
+#define NRF51_GPIO_SIZE 0x1000
+
+#define NRF51_GPIO_REG_OUT 0x504
+#define NRF51_GPIO_REG_OUTSET 0x508
+#define NRF51_GPIO_REG_OUTCLR 0x50C
+#define NRF51_GPIO_REG_IN 0x510
+#define NRF51_GPIO_REG_DIR 0x514
+#define NRF51_GPIO_REG_DIRSET 0x518
+#define NRF51_GPIO_REG_DIRCLR 0x51C
+#define NRF51_GPIO_REG_CNF_START 0x700
+#define NRF51_GPIO_REG_CNF_END 0x77F
+
+#define NRF51_GPIO_PULLDOWN 1
+#define NRF51_GPIO_PULLUP 3
+
+typedef struct NRF51GPIOState {
+ SysBusDevice parent_obj;
+
+ MemoryRegion mmio;
+ qemu_irq irq;
+
+ uint32_t out;
+ uint32_t in;
+ uint32_t in_mask;
+ uint32_t dir;
+ uint32_t cnf[NRF51_GPIO_PINS];
+
+ uint32_t old_out;
+ uint32_t old_out_connected;
+
+ qemu_irq output[NRF51_GPIO_PINS];
+} NRF51GPIOState;
+
+
+#endif