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-rw-r--r--src/hw/gpio/imx_gpio.c341
1 files changed, 341 insertions, 0 deletions
diff --git a/src/hw/gpio/imx_gpio.c b/src/hw/gpio/imx_gpio.c
new file mode 100644
index 0000000..3170585
--- /dev/null
+++ b/src/hw/gpio/imx_gpio.c
@@ -0,0 +1,341 @@
+/*
+ * i.MX processors GPIO emulation.
+ *
+ * Copyright (C) 2015 Jean-Christophe Dubois <jcd@tribudubois.net>
+ *
+ * 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 or
+ * (at your option) version 3 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * 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/gpio/imx_gpio.h"
+
+#ifndef DEBUG_IMX_GPIO
+#define DEBUG_IMX_GPIO 0
+#endif
+
+typedef enum IMXGPIOLevel {
+ IMX_GPIO_LEVEL_LOW = 0,
+ IMX_GPIO_LEVEL_HIGH = 1,
+} IMXGPIOLevel;
+
+#define DPRINTF(fmt, args...) \
+ do { \
+ if (DEBUG_IMX_GPIO) { \
+ fprintf(stderr, "[%s]%s: " fmt , TYPE_IMX_GPIO, \
+ __func__, ##args); \
+ } \
+ } while (0)
+
+static const char *imx_gpio_reg_name(uint32_t reg)
+{
+ switch (reg) {
+ case DR_ADDR:
+ return "DR";
+ case GDIR_ADDR:
+ return "GDIR";
+ case PSR_ADDR:
+ return "PSR";
+ case ICR1_ADDR:
+ return "ICR1";
+ case ICR2_ADDR:
+ return "ICR2";
+ case IMR_ADDR:
+ return "IMR";
+ case ISR_ADDR:
+ return "ISR";
+ case EDGE_SEL_ADDR:
+ return "EDGE_SEL";
+ default:
+ return "[?]";
+ }
+}
+
+static void imx_gpio_update_int(IMXGPIOState *s)
+{
+ qemu_set_irq(s->irq, (s->isr & s->imr) ? 1 : 0);
+}
+
+static void imx_gpio_set_int_line(IMXGPIOState *s, int line, IMXGPIOLevel level)
+{
+ /* if this signal isn't configured as an input signal, nothing to do */
+ if (!extract32(s->gdir, line, 1)) {
+ return;
+ }
+
+ /* When set, EDGE_SEL overrides the ICR config */
+ if (extract32(s->edge_sel, line, 1)) {
+ /* we detect interrupt on rising and falling edge */
+ if (extract32(s->psr, line, 1) != level) {
+ /* level changed */
+ s->isr = deposit32(s->isr, line, 1, 1);
+ }
+ } else if (extract64(s->icr, 2*line + 1, 1)) {
+ /* interrupt is edge sensitive */
+ if (extract32(s->psr, line, 1) != level) {
+ /* level changed */
+ if (extract64(s->icr, 2*line, 1) != level) {
+ s->isr = deposit32(s->isr, line, 1, 1);
+ }
+ }
+ } else {
+ /* interrupt is level sensitive */
+ if (extract64(s->icr, 2*line, 1) == level) {
+ s->isr = deposit32(s->isr, line, 1, 1);
+ }
+ }
+}
+
+static void imx_gpio_set(void *opaque, int line, int level)
+{
+ IMXGPIOState *s = IMX_GPIO(opaque);
+ IMXGPIOLevel imx_level = level ? IMX_GPIO_LEVEL_HIGH : IMX_GPIO_LEVEL_LOW;
+
+ imx_gpio_set_int_line(s, line, imx_level);
+
+ /* this is an input signal, so set PSR */
+ s->psr = deposit32(s->psr, line, 1, imx_level);
+
+ imx_gpio_update_int(s);
+}
+
+static void imx_gpio_set_all_int_lines(IMXGPIOState *s)
+{
+ int i;
+
+ for (i = 0; i < IMX_GPIO_PIN_COUNT; i++) {
+ IMXGPIOLevel imx_level = extract32(s->psr, i, 1);
+ imx_gpio_set_int_line(s, i, imx_level);
+ }
+
+ imx_gpio_update_int(s);
+}
+
+static inline void imx_gpio_set_all_output_lines(IMXGPIOState *s)
+{
+ int i;
+
+ for (i = 0; i < IMX_GPIO_PIN_COUNT; i++) {
+ /*
+ * if the line is set as output, then forward the line
+ * level to its user.
+ */
+ if (extract32(s->gdir, i, 1) && s->output[i]) {
+ qemu_set_irq(s->output[i], extract32(s->dr, i, 1));
+ }
+ }
+}
+
+static uint64_t imx_gpio_read(void *opaque, hwaddr offset, unsigned size)
+{
+ IMXGPIOState *s = IMX_GPIO(opaque);
+ uint32_t reg_value = 0;
+
+ switch (offset) {
+ case DR_ADDR:
+ /*
+ * depending on the "line" configuration, the bit values
+ * are coming either from DR or PSR
+ */
+ reg_value = (s->dr & s->gdir) | (s->psr & ~s->gdir);
+ break;
+
+ case GDIR_ADDR:
+ reg_value = s->gdir;
+ break;
+
+ case PSR_ADDR:
+ reg_value = s->psr & ~s->gdir;
+ break;
+
+ case ICR1_ADDR:
+ reg_value = extract64(s->icr, 0, 32);
+ break;
+
+ case ICR2_ADDR:
+ reg_value = extract64(s->icr, 32, 32);
+ break;
+
+ case IMR_ADDR:
+ reg_value = s->imr;
+ break;
+
+ case ISR_ADDR:
+ reg_value = s->isr;
+ break;
+
+ case EDGE_SEL_ADDR:
+ if (s->has_edge_sel) {
+ reg_value = s->edge_sel;
+ } else {
+ qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: EDGE_SEL register not "
+ "present on this version of GPIO device\n",
+ TYPE_IMX_GPIO, __func__);
+ }
+ break;
+
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
+ HWADDR_PRIx "\n", TYPE_IMX_GPIO, __func__, offset);
+ break;
+ }
+
+ DPRINTF("(%s) = 0x%" PRIx32 "\n", imx_gpio_reg_name(offset), reg_value);
+
+ return reg_value;
+}
+
+static void imx_gpio_write(void *opaque, hwaddr offset, uint64_t value,
+ unsigned size)
+{
+ IMXGPIOState *s = IMX_GPIO(opaque);
+
+ DPRINTF("(%s, value = 0x%" PRIx32 ")\n", imx_gpio_reg_name(offset),
+ (uint32_t)value);
+
+ switch (offset) {
+ case DR_ADDR:
+ s->dr = value;
+ imx_gpio_set_all_output_lines(s);
+ break;
+
+ case GDIR_ADDR:
+ s->gdir = value;
+ imx_gpio_set_all_output_lines(s);
+ imx_gpio_set_all_int_lines(s);
+ break;
+
+ case ICR1_ADDR:
+ s->icr = deposit64(s->icr, 0, 32, value);
+ imx_gpio_set_all_int_lines(s);
+ break;
+
+ case ICR2_ADDR:
+ s->icr = deposit64(s->icr, 32, 32, value);
+ imx_gpio_set_all_int_lines(s);
+ break;
+
+ case IMR_ADDR:
+ s->imr = value;
+ imx_gpio_update_int(s);
+ break;
+
+ case ISR_ADDR:
+ s->isr |= ~value;
+ imx_gpio_set_all_int_lines(s);
+ break;
+
+ case EDGE_SEL_ADDR:
+ if (s->has_edge_sel) {
+ s->edge_sel = value;
+ imx_gpio_set_all_int_lines(s);
+ } else {
+ qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: EDGE_SEL register not "
+ "present on this version of GPIO device\n",
+ TYPE_IMX_GPIO, __func__);
+ }
+ break;
+
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
+ HWADDR_PRIx "\n", TYPE_IMX_GPIO, __func__, offset);
+ break;
+ }
+
+ return;
+}
+
+static const MemoryRegionOps imx_gpio_ops = {
+ .read = imx_gpio_read,
+ .write = imx_gpio_write,
+ .valid.min_access_size = 4,
+ .valid.max_access_size = 4,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static const VMStateDescription vmstate_imx_gpio = {
+ .name = TYPE_IMX_GPIO,
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .minimum_version_id_old = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32(dr, IMXGPIOState),
+ VMSTATE_UINT32(gdir, IMXGPIOState),
+ VMSTATE_UINT32(psr, IMXGPIOState),
+ VMSTATE_UINT64(icr, IMXGPIOState),
+ VMSTATE_UINT32(imr, IMXGPIOState),
+ VMSTATE_UINT32(isr, IMXGPIOState),
+ VMSTATE_BOOL(has_edge_sel, IMXGPIOState),
+ VMSTATE_UINT32(edge_sel, IMXGPIOState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static Property imx_gpio_properties[] = {
+ DEFINE_PROP_BOOL("has-edge-sel", IMXGPIOState, has_edge_sel, true),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void imx_gpio_reset(DeviceState *dev)
+{
+ IMXGPIOState *s = IMX_GPIO(dev);
+
+ s->dr = 0;
+ s->gdir = 0;
+ s->psr = 0;
+ s->icr = 0;
+ s->imr = 0;
+ s->isr = 0;
+ s->edge_sel = 0;
+
+ imx_gpio_set_all_output_lines(s);
+ imx_gpio_update_int(s);
+}
+
+static void imx_gpio_realize(DeviceState *dev, Error **errp)
+{
+ IMXGPIOState *s = IMX_GPIO(dev);
+
+ memory_region_init_io(&s->iomem, OBJECT(s), &imx_gpio_ops, s,
+ TYPE_IMX_GPIO, IMX_GPIO_MEM_SIZE);
+
+ qdev_init_gpio_in(DEVICE(s), imx_gpio_set, IMX_GPIO_PIN_COUNT);
+ qdev_init_gpio_out(DEVICE(s), s->output, IMX_GPIO_PIN_COUNT);
+
+ sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq);
+ sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem);
+}
+
+static void imx_gpio_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->realize = imx_gpio_realize;
+ dc->reset = imx_gpio_reset;
+ dc->props = imx_gpio_properties;
+ dc->vmsd = &vmstate_imx_gpio;
+ dc->desc = "i.MX GPIO controller";
+}
+
+static const TypeInfo imx_gpio_info = {
+ .name = TYPE_IMX_GPIO,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(IMXGPIOState),
+ .class_init = imx_gpio_class_init,
+};
+
+static void imx_gpio_register_types(void)
+{
+ type_register_static(&imx_gpio_info);
+}
+
+type_init(imx_gpio_register_types)
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