Although very similar to the STM32F4xx EXTI, STM32L4x5 EXTI generates
more than 32 event/interrupt requests and thus uses more registers
than STM32F4xx EXTI which generates 23 event/interrupt requests.
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Arnaud Minier <arnaud.minier@telecom-paris.fr>
Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>
---
Should the for loop variables be `unsigned` rather than `int` ?
docs/system/arm/b-l475e-iot01a.rst | 5 +-
hw/misc/Kconfig | 3 +
hw/misc/meson.build | 1 +
hw/misc/stm32l4x5_exti.c | 292 +++++++++++++++++++++++++++++
hw/misc/trace-events | 5 +
include/hw/misc/stm32l4x5_exti.h | 51 +++++
6 files changed, 354 insertions(+), 3 deletions(-)
create mode 100644 hw/misc/stm32l4x5_exti.c
create mode 100644 include/hw/misc/stm32l4x5_exti.h
diff --git a/docs/system/arm/b-l475e-iot01a.rst b/docs/system/arm/b-l475e-iot01a.rst
index 2b128e6b84..72f256ace7 100644
--- a/docs/system/arm/b-l475e-iot01a.rst
+++ b/docs/system/arm/b-l475e-iot01a.rst
@@ -12,17 +12,16 @@ USART, I2C, SPI, CAN and USB OTG, as well as a variety of sensors.
Supported devices
"""""""""""""""""
-Currently, B-L475E-IOT01A machine's implementation is minimal,
-it only supports the following device:
+Currently B-L475E-IOT01A machine's only supports the following devices:
- Cortex-M4F based STM32L4x5 SoC
+- STM32L4x5 EXTI (Extended interrupts and events controller)
Missing devices
"""""""""""""""
The B-L475E-IOT01A does *not* support the following devices:
-- Extended interrupts and events controller (EXTI)
- Reset and clock control (RCC)
- Serial ports (UART)
- System configuration controller (SYSCFG)
diff --git a/hw/misc/Kconfig b/hw/misc/Kconfig
index cc8a8c1418..3efe3dc2cc 100644
--- a/hw/misc/Kconfig
+++ b/hw/misc/Kconfig
@@ -87,6 +87,9 @@ config STM32F4XX_SYSCFG
config STM32F4XX_EXTI
bool
+config STM32L4X5_EXTI
+ bool
+
config MIPS_ITU
bool
diff --git a/hw/misc/meson.build b/hw/misc/meson.build
index 36c20d5637..16db6e228d 100644
--- a/hw/misc/meson.build
+++ b/hw/misc/meson.build
@@ -110,6 +110,7 @@ system_ss.add(when: 'CONFIG_XLNX_VERSAL_TRNG', if_true: files(
system_ss.add(when: 'CONFIG_STM32F2XX_SYSCFG', if_true: files('stm32f2xx_syscfg.c'))
system_ss.add(when: 'CONFIG_STM32F4XX_SYSCFG', if_true: files('stm32f4xx_syscfg.c'))
system_ss.add(when: 'CONFIG_STM32F4XX_EXTI', if_true: files('stm32f4xx_exti.c'))
+system_ss.add(when: 'CONFIG_STM32L4X5_EXTI', if_true: files('stm32l4x5_exti.c'))
system_ss.add(when: 'CONFIG_MPS2_FPGAIO', if_true: files('mps2-fpgaio.c'))
system_ss.add(when: 'CONFIG_MPS2_SCC', if_true: files('mps2-scc.c'))
diff --git a/hw/misc/stm32l4x5_exti.c b/hw/misc/stm32l4x5_exti.c
new file mode 100644
index 0000000000..aedf1fb370
--- /dev/null
+++ b/hw/misc/stm32l4x5_exti.c
@@ -0,0 +1,292 @@
+/*
+ * STM32L4x5 EXTI (Extended interrupts and events controller)
+ *
+ * Copyright (c) 2023 Arnaud Minier <arnaud.minier@telecom-paris.fr>
+ * Copyright (c) 2023 Samuel Tardieu <samuel.tardieu@telecom-paris.fr>
+ * Copyright (c) 2023 Inès Varhol <ines.varhol@telecom-paris.fr>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ * This work is based on the stm32f4xx_exti by Alistair Francis.
+ * Original code is licensed under the MIT License:
+ *
+ * Copyright (c) 2014 Alistair Francis <alistair@alistair23.me>
+ */
+
+/*
+ * The reference used is the STMicroElectronics RM0351 Reference manual
+ * for STM32L4x5 and STM32L4x6 advanced Arm ® -based 32-bit MCUs.
+ * https://www.st.com/en/microcontrollers-microprocessors/stm32l4x5/documentation.html
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "trace.h"
+#include "hw/irq.h"
+#include "migration/vmstate.h"
+#include "hw/misc/stm32l4x5_exti.h"
+
+#define EXTI_IMR1 0x00
+#define EXTI_EMR1 0x04
+#define EXTI_RTSR1 0x08
+#define EXTI_FTSR1 0x0C
+#define EXTI_SWIER1 0x10
+#define EXTI_PR1 0x14
+#define EXTI_IMR2 0x20
+#define EXTI_EMR2 0x24
+#define EXTI_RTSR2 0x28
+#define EXTI_FTSR2 0x2C
+#define EXTI_SWIER2 0x30
+#define EXTI_PR2 0x34
+
+#define EXTI_NUM_GPIO_EVENT_IN_LINES 16
+
+/* 0b11111111_10000010_00000000_00000000 */
+#define DIRECT_LINE_MASK1 0xFF820000
+/* 0b00000000_00000000_00000000_10000111 */
+#define DIRECT_LINE_MASK2 0x00000087
+/* 0b11111111_11111111_11111111_00000000 */
+#define RESERVED_BITS_MASK2 0xFFFFFF00
+
+/* 0b00000000_00000000_00000000_01111000 */
+#define ACTIVABLE_MASK2 (~DIRECT_LINE_MASK2 & ~RESERVED_BITS_MASK2)
+
+static void stm32l4x5_exti_reset_hold(Object *obj)
+{
+ Stm32l4x5ExtiState *s = STM32L4X5_EXTI(obj);
+
+ s->imr[0] = DIRECT_LINE_MASK1;
+ s->emr[0] = 0x00000000;
+ s->rtsr[0] = 0x00000000;
+ s->ftsr[0] = 0x00000000;
+ s->swier[0] = 0x00000000;
+ s->pr[0] = 0x00000000;
+
+ s->imr[1] = DIRECT_LINE_MASK2;
+ s->emr[1] = 0x00000000;
+ s->rtsr[1] = 0x00000000;
+ s->ftsr[1] = 0x00000000;
+ s->swier[1] = 0x00000000;
+ s->pr[1] = 0x00000000;
+}
+
+static void stm32l4x5_exti_set_irq(void *opaque, int irq, int level)
+{
+ Stm32l4x5ExtiState *s = opaque;
+ const unsigned n = irq >= 32;
+ const int oirq = irq;
+
+ trace_stm32l4x5_exti_set_irq(irq, level);
+
+ if (irq >= 32) {
+ /* Shift the value to enable access in x2 registers. */
+ irq -= 32;
+ }
+
+ /* If the interrupt is masked, pr won't be raised */
+ if (!((1 << irq) & s->imr[n])) {
+ return;
+ }
+
+ if (((1 << irq) & s->rtsr[n]) && level) {
+ /* Rising Edge */
+ s->pr[n] |= 1 << irq;
+ qemu_irq_pulse(s->irq[oirq]);
+ } else if (((1 << irq) & s->ftsr[n]) && !level) {
+ /* Falling Edge */
+ s->pr[n] |= 1 << irq;
+ qemu_irq_pulse(s->irq[oirq]);
+ }
+
+}
+
+static uint64_t stm32l4x5_exti_read(void *opaque, hwaddr addr,
+ unsigned int size)
+{
+ Stm32l4x5ExtiState *s = opaque;
+ uint32_t r = 0;
+ const unsigned n = addr >= EXTI_IMR2;
+
+ switch (addr) {
+ case EXTI_IMR1:
+ case EXTI_IMR2:
+ r = s->imr[n];
+ break;
+ case EXTI_EMR1:
+ case EXTI_EMR2:
+ r = s->emr[n];
+ break;
+ case EXTI_RTSR1:
+ case EXTI_RTSR2:
+ r = s->rtsr[n];
+ break;
+ case EXTI_FTSR1:
+ case EXTI_FTSR2:
+ r = s->ftsr[n];
+ break;
+ case EXTI_SWIER1:
+ case EXTI_SWIER2:
+ r = s->swier[n];
+ break;
+ case EXTI_PR1:
+ case EXTI_PR2:
+ r = s->pr[n];
+ break;
+
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "STM32L4X5_exti_read: Bad offset 0x%x\n", (int)addr);
+ break;
+ }
+
+ trace_stm32l4x5_exti_read(addr, r);
+
+ return r;
+}
+
+static void stm32l4x5_exti_write(void *opaque, hwaddr addr,
+ uint64_t val64, unsigned int size)
+{
+ Stm32l4x5ExtiState *s = opaque;
+ const uint32_t value = (uint32_t)val64;
+
+ trace_stm32l4x5_exti_write(addr, value);
+
+ switch (addr) {
+ case EXTI_IMR1:
+ s->imr[0] = value;
+ return;
+ case EXTI_EMR1:
+ s->emr[0] = value;
+ return;
+ case EXTI_RTSR1:
+ s->rtsr[0] = value & ~DIRECT_LINE_MASK1;
+ return;
+ case EXTI_FTSR1:
+ s->ftsr[0] = value & ~DIRECT_LINE_MASK1;
+ return;
+ case EXTI_SWIER1: {
+ const uint32_t set1 = value & ~DIRECT_LINE_MASK1;
+ const uint32_t pend1 = set1 & ~s->swier[0] & s->imr[0] & ~s->pr[0];
+ s->swier[0] = set1;
+ s->pr[0] |= pend1;
+ for (int i = 0; i < 32; i++) {
+ if (pend1 & (1 << i)) {
+ qemu_irq_pulse(s->irq[i]);
+ }
+ }
+ return;
+ }
+ case EXTI_PR1: {
+ const uint32_t cleared1 = s->pr[0] & value & ~DIRECT_LINE_MASK1;
+ /* This bit is cleared by writing a 1 to it */
+ s->pr[0] &= ~cleared1;
+ /* Software triggered interrupts are cleared as well */
+ s->swier[0] &= ~cleared1;
+ return;
+ }
+ case EXTI_IMR2:
+ s->imr[1] = value & ~RESERVED_BITS_MASK2;
+ return;
+ case EXTI_EMR2:
+ s->emr[1] = value & ~RESERVED_BITS_MASK2;
+ return;
+ case EXTI_RTSR2:
+ s->rtsr[1] = value & ACTIVABLE_MASK2;
+ return;
+ case EXTI_FTSR2:
+ s->ftsr[1] = value & ACTIVABLE_MASK2;
+ return;
+ case EXTI_SWIER2: {
+ const uint32_t set2 = value & ACTIVABLE_MASK2;
+ const uint32_t pend2 = set2 & ~s->swier[1] & s->imr[1] & ~s->pr[1];
+ s->swier[1] = set2;
+ s->pr[1] |= pend2;
+ for (int i = 0; i < 8; i++) {
+ if (pend2 & (1 << i)) {
+ qemu_irq_pulse(s->irq[32 + i]);
+ }
+ }
+ return;
+ }
+ case EXTI_PR2: {
+ const uint32_t cleared = s->pr[1] & value & ACTIVABLE_MASK2;
+ /* This bit is cleared by writing a 1 to it */
+ s->pr[1] &= ~cleared;
+ /* Software triggered interrupts are cleared as well */
+ s->swier[1] &= ~cleared;
+ return;
+ }
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "STM32L4X5_exti_write: Bad offset 0x%x\n", (int)addr);
+ }
+}
+
+static const MemoryRegionOps stm32l4x5_exti_ops = {
+ .read = stm32l4x5_exti_read,
+ .write = stm32l4x5_exti_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+ .impl.min_access_size = 4,
+ .impl.max_access_size = 4,
+ .impl.unaligned = false,
+ .valid.min_access_size = 4,
+ .valid.max_access_size = 4,
+ .valid.unaligned = false,
+};
+
+static void stm32l4x5_exti_init(Object *obj)
+{
+ Stm32l4x5ExtiState *s = STM32L4X5_EXTI(obj);
+ int i;
+
+ for (i = 0; i < EXTI_NUM_INTERRUPT_OUT_LINES; i++) {
+ sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq[i]);
+ }
+
+ memory_region_init_io(&s->mmio, obj, &stm32l4x5_exti_ops, s,
+ TYPE_STM32L4X5_EXTI, 0x400);
+ sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
+
+ qdev_init_gpio_in(DEVICE(obj), stm32l4x5_exti_set_irq,
+ EXTI_NUM_GPIO_EVENT_IN_LINES);
+}
+
+static const VMStateDescription vmstate_stm32l4x5_exti = {
+ .name = TYPE_STM32L4X5_EXTI,
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32_ARRAY(imr, Stm32l4x5ExtiState, EXTI_NUM_REGISTER),
+ VMSTATE_UINT32_ARRAY(emr, Stm32l4x5ExtiState, EXTI_NUM_REGISTER),
+ VMSTATE_UINT32_ARRAY(rtsr, Stm32l4x5ExtiState, EXTI_NUM_REGISTER),
+ VMSTATE_UINT32_ARRAY(ftsr, Stm32l4x5ExtiState, EXTI_NUM_REGISTER),
+ VMSTATE_UINT32_ARRAY(swier, Stm32l4x5ExtiState, EXTI_NUM_REGISTER),
+ VMSTATE_UINT32_ARRAY(pr, Stm32l4x5ExtiState, EXTI_NUM_REGISTER),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void stm32l4x5_exti_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ ResettableClass *rc = RESETTABLE_CLASS(klass);
+
+ dc->vmsd = &vmstate_stm32l4x5_exti;
+ rc->phases.hold = stm32l4x5_exti_reset_hold;
+}
+
+static const TypeInfo stm32l4x5_exti_types[] = {
+ {
+ .name = TYPE_STM32L4X5_EXTI,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(Stm32l4x5ExtiState),
+ .instance_init = stm32l4x5_exti_init,
+ .class_init = stm32l4x5_exti_class_init,
+ }
+};
+
+DEFINE_TYPES(stm32l4x5_exti_types)
diff --git a/hw/misc/trace-events b/hw/misc/trace-events
index 85725506bf..fccd3204bf 100644
--- a/hw/misc/trace-events
+++ b/hw/misc/trace-events
@@ -163,6 +163,11 @@ stm32f4xx_exti_set_irq(int irq, int level) "Set EXTI: %d to %d"
stm32f4xx_exti_read(uint64_t addr) "reg read: addr: 0x%" PRIx64 " "
stm32f4xx_exti_write(uint64_t addr, uint64_t data) "reg write: addr: 0x%" PRIx64 " val: 0x%" PRIx64 ""
+# stm32l4x5_exti.c
+stm32l4x5_exti_set_irq(int irq, int level) "Set EXTI: %d to %d"
+stm32l4x5_exti_read(uint64_t addr, uint64_t data) "reg read: addr: 0x%" PRIx64 " val: 0x%" PRIx64 ""
+stm32l4x5_exti_write(uint64_t addr, uint64_t data) "reg write: addr: 0x%" PRIx64 " val: 0x%" PRIx64 ""
+
# tz-mpc.c
tz_mpc_reg_read(uint32_t offset, uint64_t data, unsigned size) "TZ MPC regs read: offset 0x%x data 0x%" PRIx64 " size %u"
tz_mpc_reg_write(uint32_t offset, uint64_t data, unsigned size) "TZ MPC regs write: offset 0x%x data 0x%" PRIx64 " size %u"
diff --git a/include/hw/misc/stm32l4x5_exti.h b/include/hw/misc/stm32l4x5_exti.h
new file mode 100644
index 0000000000..be961d2f01
--- /dev/null
+++ b/include/hw/misc/stm32l4x5_exti.h
@@ -0,0 +1,51 @@
+/*
+ * STM32L4x5 EXTI (Extended interrupts and events controller)
+ *
+ * Copyright (c) 2023 Arnaud Minier <arnaud.minier@telecom-paris.fr>
+ * Copyright (c) 2023 Inès Varhol <ines.varhol@telecom-paris.fr>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ * This work is based on the stm32f4xx_exti by Alistair Francis.
+ * Original code is licensed under the MIT License:
+ *
+ * Copyright (c) 2014 Alistair Francis <alistair@alistair23.me>
+ */
+
+/*
+ * The reference used is the STMicroElectronics RM0351 Reference manual
+ * for STM32L4x5 and STM32L4x6 advanced Arm ® -based 32-bit MCUs.
+ * https://www.st.com/en/microcontrollers-microprocessors/stm32l4x5/documentation.html
+ */
+
+#ifndef HW_STM32L4X5_EXTI_H
+#define HW_STM32L4X5_EXTI_H
+
+#include "hw/sysbus.h"
+#include "qom/object.h"
+
+#define TYPE_STM32L4X5_EXTI "stm32l4x5-exti"
+OBJECT_DECLARE_SIMPLE_TYPE(Stm32l4x5ExtiState, STM32L4X5_EXTI)
+
+#define EXTI_NUM_INTERRUPT_OUT_LINES 40
+#define EXTI_NUM_REGISTER 2
+
+struct Stm32l4x5ExtiState {
+ SysBusDevice parent_obj;
+
+ MemoryRegion mmio;
+
+ uint32_t imr[EXTI_NUM_REGISTER];
+ uint32_t emr[EXTI_NUM_REGISTER];
+ uint32_t rtsr[EXTI_NUM_REGISTER];
+ uint32_t ftsr[EXTI_NUM_REGISTER];
+ uint32_t swier[EXTI_NUM_REGISTER];
+ uint32_t pr[EXTI_NUM_REGISTER];
+
+ qemu_irq irq[EXTI_NUM_INTERRUPT_OUT_LINES];
+};
+
+#endif
--
2.43.0On 8/1/24 19:03, Inès Varhol wrote:
> Although very similar to the STM32F4xx EXTI, STM32L4x5 EXTI generates
> more than 32 event/interrupt requests and thus uses more registers
> than STM32F4xx EXTI which generates 23 event/interrupt requests.
>
> Acked-by: Alistair Francis <alistair.francis@wdc.com>
> Signed-off-by: Arnaud Minier <arnaud.minier@telecom-paris.fr>
> Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>
> ---
>
> Should the for loop variables be `unsigned` rather than `int` ?
It depends on the iterated range. Here you iterate over
ARRAY_SIZE(Stm32l4x5ExtiState::irq) which is a size_t type,
which is unsigned. Amusingly we use both similarly:
$ git grep 'for (size_t' | wc -l
56
$ git grep 'for (unsigned' | wc -l
59
> docs/system/arm/b-l475e-iot01a.rst | 5 +-
> hw/misc/Kconfig | 3 +
> hw/misc/meson.build | 1 +
> hw/misc/stm32l4x5_exti.c | 292 +++++++++++++++++++++++++++++
> hw/misc/trace-events | 5 +
> include/hw/misc/stm32l4x5_exti.h | 51 +++++
> 6 files changed, 354 insertions(+), 3 deletions(-)
> create mode 100644 hw/misc/stm32l4x5_exti.c
> create mode 100644 include/hw/misc/stm32l4x5_exti.h
>
> diff --git a/docs/system/arm/b-l475e-iot01a.rst b/docs/system/arm/b-l475e-iot01a.rst
> index 2b128e6b84..72f256ace7 100644
> --- a/docs/system/arm/b-l475e-iot01a.rst
> +++ b/docs/system/arm/b-l475e-iot01a.rst
> @@ -12,17 +12,16 @@ USART, I2C, SPI, CAN and USB OTG, as well as a variety of sensors.
> Supported devices
> """""""""""""""""
>
> -Currently, B-L475E-IOT01A machine's implementation is minimal,
> -it only supports the following device:
> +Currently B-L475E-IOT01A machine's only supports the following devices:
>
> - Cortex-M4F based STM32L4x5 SoC
> +- STM32L4x5 EXTI (Extended interrupts and events controller)
>
> Missing devices
> """""""""""""""
>
> The B-L475E-IOT01A does *not* support the following devices:
>
> -- Extended interrupts and events controller (EXTI)
> - Reset and clock control (RCC)
> - Serial ports (UART)
> - System configuration controller (SYSCFG)
> diff --git a/hw/misc/Kconfig b/hw/misc/Kconfig
> index cc8a8c1418..3efe3dc2cc 100644
> --- a/hw/misc/Kconfig
> +++ b/hw/misc/Kconfig
> @@ -87,6 +87,9 @@ config STM32F4XX_SYSCFG
> config STM32F4XX_EXTI
> bool
>
> +config STM32L4X5_EXTI
> + bool
> +
> config MIPS_ITU
> bool
>
> diff --git a/hw/misc/meson.build b/hw/misc/meson.build
> index 36c20d5637..16db6e228d 100644
> --- a/hw/misc/meson.build
> +++ b/hw/misc/meson.build
> @@ -110,6 +110,7 @@ system_ss.add(when: 'CONFIG_XLNX_VERSAL_TRNG', if_true: files(
> system_ss.add(when: 'CONFIG_STM32F2XX_SYSCFG', if_true: files('stm32f2xx_syscfg.c'))
> system_ss.add(when: 'CONFIG_STM32F4XX_SYSCFG', if_true: files('stm32f4xx_syscfg.c'))
> system_ss.add(when: 'CONFIG_STM32F4XX_EXTI', if_true: files('stm32f4xx_exti.c'))
> +system_ss.add(when: 'CONFIG_STM32L4X5_EXTI', if_true: files('stm32l4x5_exti.c'))
> system_ss.add(when: 'CONFIG_MPS2_FPGAIO', if_true: files('mps2-fpgaio.c'))
> system_ss.add(when: 'CONFIG_MPS2_SCC', if_true: files('mps2-scc.c'))
>
> diff --git a/hw/misc/stm32l4x5_exti.c b/hw/misc/stm32l4x5_exti.c
> new file mode 100644
> index 0000000000..aedf1fb370
> --- /dev/null
> +++ b/hw/misc/stm32l4x5_exti.c
> @@ -0,0 +1,292 @@
> +/*
> + * STM32L4x5 EXTI (Extended interrupts and events controller)
> + *
> + * Copyright (c) 2023 Arnaud Minier <arnaud.minier@telecom-paris.fr>
> + * Copyright (c) 2023 Samuel Tardieu <samuel.tardieu@telecom-paris.fr>
> + * Copyright (c) 2023 Inès Varhol <ines.varhol@telecom-paris.fr>
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + *
> + * This work is based on the stm32f4xx_exti by Alistair Francis.
> + * Original code is licensed under the MIT License:
> + *
> + * Copyright (c) 2014 Alistair Francis <alistair@alistair23.me>
> + */
> +
> +/*
> + * The reference used is the STMicroElectronics RM0351 Reference manual
> + * for STM32L4x5 and STM32L4x6 advanced Arm ® -based 32-bit MCUs.
> + * https://www.st.com/en/microcontrollers-microprocessors/stm32l4x5/documentation.html
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu/log.h"
> +#include "trace.h"
> +#include "hw/irq.h"
> +#include "migration/vmstate.h"
> +#include "hw/misc/stm32l4x5_exti.h"
> +
> +#define EXTI_IMR1 0x00
> +#define EXTI_EMR1 0x04
> +#define EXTI_RTSR1 0x08
> +#define EXTI_FTSR1 0x0C
> +#define EXTI_SWIER1 0x10
> +#define EXTI_PR1 0x14
> +#define EXTI_IMR2 0x20
> +#define EXTI_EMR2 0x24
> +#define EXTI_RTSR2 0x28
> +#define EXTI_FTSR2 0x2C
> +#define EXTI_SWIER2 0x30
> +#define EXTI_PR2 0x34
> +
> +#define EXTI_NUM_GPIO_EVENT_IN_LINES 16
#define EXTI_MAX_IRQ_PER_BANK 32
> +
> +/* 0b11111111_10000010_00000000_00000000 */
> +#define DIRECT_LINE_MASK1 0xFF820000
> +/* 0b00000000_00000000_00000000_10000111 */
> +#define DIRECT_LINE_MASK2 0x00000087
> +/* 0b11111111_11111111_11111111_00000000 */
> +#define RESERVED_BITS_MASK2 0xFFFFFF00
> +
> +/* 0b00000000_00000000_00000000_01111000 */
> +#define ACTIVABLE_MASK2 (~DIRECT_LINE_MASK2 & ~RESERVED_BITS_MASK2)
You might want to declare:
#define EXTI_IRQS_BANK0 32
#define EXTI_IRQS_BANK1 8
static const unsigned irqs_per_bank[EXTI_NUM_REGISTER] = {
EXTI_IRQS_BANK0,
EXTI_IRQS_BANK1,
};
static const uint32_t exti_romask[EXTI_NUM_REGISTER] = {
0xff820000, /* 0b11111111_10000010_00000000_00000000 */
0x00000087, /* 0b00000000_00000000_00000000_10000111 */
};
And add descriptive helpers such:
static unsigned regbank_index_by_irq(unsigned irq)
{
return irq >= EXTI_MAX_IRQ_PER_BANK ? 1 : 0;
}
static unsigned regbank_index_by_addr(hwaddr addr)
{
return addr >= EXTI_IMR2 ? 1 : 0;
}
static unsigned valid_mask(unsigned bank)
{
return MAKE_64BIT_MASK(0, irqs_per_bank[bank]);
}
(then see below)
> +static void stm32l4x5_exti_reset_hold(Object *obj)
> +{
> + Stm32l4x5ExtiState *s = STM32L4X5_EXTI(obj);
> +
> + s->imr[0] = DIRECT_LINE_MASK1;
> + s->emr[0] = 0x00000000;
> + s->rtsr[0] = 0x00000000;
> + s->ftsr[0] = 0x00000000;
> + s->swier[0] = 0x00000000;
> + s->pr[0] = 0x00000000;
> +
> + s->imr[1] = DIRECT_LINE_MASK2;
> + s->emr[1] = 0x00000000;
> + s->rtsr[1] = 0x00000000;
> + s->ftsr[1] = 0x00000000;
> + s->swier[1] = 0x00000000;
> + s->pr[1] = 0x00000000;
> +}
BTW stm32l4x5_exti_reset_hold() can also be unified:
static void stm32l4x5_exti_reset_hold(Object *obj)
{
Stm32l4x5ExtiState *s = STM32L4X5_EXTI(obj);
for (unsigned bank = 0; bank < EXTI_NUM_REGISTER; bank++) {
s->imr[bank] = exti_romask[bank];
s->emr[bank] = 0;
s->rtsr[bank] = 0;
s->ftsr[bank] = 0;
s->swier[bank] = 0;
s->pr[bank] = 0;
}
}
> +static void stm32l4x5_exti_set_irq(void *opaque, int irq, int level)
> +{
> + Stm32l4x5ExtiState *s = opaque;
> + const unsigned n = irq >= 32;
Then:
n = regbank_index_by_irq(irq);
Maybe 'bank' is a better variable name instead of 'n', in particular
in stm32l4x5_exti_read() it makes it clear registers behave identically
for each bank of registers.
> + const int oirq = irq;
> +
> + trace_stm32l4x5_exti_set_irq(irq, level);
> +
> + if (irq >= 32) {
> + /* Shift the value to enable access in x2 registers. */
> + irq -= 32;
> + }
Alternatively:
irq %= EXTI_MAX_IRQ_PER_BANK;
> + /* If the interrupt is masked, pr won't be raised */
> + if (!((1 << irq) & s->imr[n])) {
Alternatively:
if (!extract32(s->imr[n], irq, 1)) {
> + return;
> + }
> +
> + if (((1 << irq) & s->rtsr[n]) && level) {
> + /* Rising Edge */
> + s->pr[n] |= 1 << irq;
> + qemu_irq_pulse(s->irq[oirq]);
> + } else if (((1 << irq) & s->ftsr[n]) && !level) {
> + /* Falling Edge */
> + s->pr[n] |= 1 << irq;
> + qemu_irq_pulse(s->irq[oirq]);
> + }
else { // Can we get here?
> +}
> +
> +static uint64_t stm32l4x5_exti_read(void *opaque, hwaddr addr,
> + unsigned int size)
> +{
> + Stm32l4x5ExtiState *s = opaque;
> + uint32_t r = 0;
> + const unsigned n = addr >= EXTI_IMR2;
bank = regbank_index_by_addr(addr);
> +
> + switch (addr) {
> + case EXTI_IMR1:
> + case EXTI_IMR2:
> + r = s->imr[n];
> + break;
> + case EXTI_EMR1:
> + case EXTI_EMR2:
> + r = s->emr[n];
> + break;
> + case EXTI_RTSR1:
> + case EXTI_RTSR2:
> + r = s->rtsr[n];
> + break;
> + case EXTI_FTSR1:
> + case EXTI_FTSR2:
> + r = s->ftsr[n];
> + break;
> + case EXTI_SWIER1:
> + case EXTI_SWIER2:
> + r = s->swier[n];
> + break;
> + case EXTI_PR1:
> + case EXTI_PR2:
> + r = s->pr[n];
> + break;
> +
> + default:
> + qemu_log_mask(LOG_GUEST_ERROR,
> + "STM32L4X5_exti_read: Bad offset 0x%x\n", (int)addr);
Here you can avoid the cast by using the HWADDR_PRIx format.
> + break;
> + }
> +
> + trace_stm32l4x5_exti_read(addr, r);
> +
> + return r;
> +}
> +
> +static void stm32l4x5_exti_write(void *opaque, hwaddr addr,
> + uint64_t val64, unsigned int size)
> +{
> + Stm32l4x5ExtiState *s = opaque;
> + const uint32_t value = (uint32_t)val64;
I don't see the benefit of casting to 32-bits, besides we have
".valid.max_access_size = 4" so the caller always pass 32-bits.
> +
> + trace_stm32l4x5_exti_write(addr, value);
> +
> + switch (addr) {
> + case EXTI_IMR1:
> + s->imr[0] = value;
> + return;
You can unify banks:
case EXTI_IMR1:
case EXTI_IMR2:
s->imr[bank] = value & valid_mask(bank);
return;
> + case EXTI_EMR1:
> + s->emr[0] = value;
> + return;
case EXTI_EMR1:
case EXTI_EMR2:
s->emr[bank] = value & valid_mask(bank);
return;
> + case EXTI_RTSR1:
> + s->rtsr[0] = value & ~DIRECT_LINE_MASK1;
> + return;
case EXTI_RTSR1:
case EXTI_RTSR2:
s->rtsr[bank] = value & ~exti_romask[bank];
return;
> + case EXTI_FTSR1:
> + s->ftsr[0] = value & ~DIRECT_LINE_MASK1;
> + return;
case EXTI_FTSR1:
case EXTI_FTSR2:
s->ftsr[bank] = value & ~exti_romask[bank];
return;
> + case EXTI_SWIER1: {
> + const uint32_t set1 = value & ~DIRECT_LINE_MASK1;
> + const uint32_t pend1 = set1 & ~s->swier[0] & s->imr[0] & ~s->pr[0];
> + s->swier[0] = set1;
> + s->pr[0] |= pend1;
> + for (int i = 0; i < 32; i++) {
> + if (pend1 & (1 << i)) {
> + qemu_irq_pulse(s->irq[i]);
> + }
> + }
> + return;
case EXTI_SWIER1:
case EXTI_SWIER2:
set = value & ~exti_romask[bank];
pend = set & ~s->swier[bank] & s->imr[bank] & ~s->pr[bank];
s->swier[bank] = set;
s->pr[bank] |= pend;
for (unsigned i = 0; i < irqs_per_bank[bank]; i++) {
if (pend & (1 << i)) { // or extract32()
qemu_irq_pulse(s->irq[i]);
}
}
return;
> + }
> + case EXTI_PR1: {
> + const uint32_t cleared1 = s->pr[0] & value & ~DIRECT_LINE_MASK1;
> + /* This bit is cleared by writing a 1 to it */
> + s->pr[0] &= ~cleared1;
> + /* Software triggered interrupts are cleared as well */
> + s->swier[0] &= ~cleared1;
> + return;
Ditto.
> + }
> + case EXTI_IMR2:
> + s->imr[1] = value & ~RESERVED_BITS_MASK2;
> + return;
> + case EXTI_EMR2:
> + s->emr[1] = value & ~RESERVED_BITS_MASK2;
> + return;
> + case EXTI_RTSR2:
> + s->rtsr[1] = value & ACTIVABLE_MASK2;
> + return;
> + case EXTI_FTSR2:
> + s->ftsr[1] = value & ACTIVABLE_MASK2;
> + return;
> + case EXTI_SWIER2: {
> + const uint32_t set2 = value & ACTIVABLE_MASK2;
> + const uint32_t pend2 = set2 & ~s->swier[1] & s->imr[1] & ~s->pr[1];
> + s->swier[1] = set2;
> + s->pr[1] |= pend2;
> + for (int i = 0; i < 8; i++) {
> + if (pend2 & (1 << i)) {
> + qemu_irq_pulse(s->irq[32 + i]);
> + }
> + }
> + return;
> + }
> + case EXTI_PR2: {
> + const uint32_t cleared = s->pr[1] & value & ACTIVABLE_MASK2;
> + /* This bit is cleared by writing a 1 to it */
> + s->pr[1] &= ~cleared;
> + /* Software triggered interrupts are cleared as well */
> + s->swier[1] &= ~cleared;
> + return;
> + }
> + default:
> + qemu_log_mask(LOG_GUEST_ERROR,
> + "STM32L4X5_exti_write: Bad offset 0x%x\n", (int)addr);
> + }
> +}
> +
> +static const MemoryRegionOps stm32l4x5_exti_ops = {
> + .read = stm32l4x5_exti_read,
> + .write = stm32l4x5_exti_write,
> + .endianness = DEVICE_NATIVE_ENDIAN,
> + .impl.min_access_size = 4,
> + .impl.max_access_size = 4,
> + .impl.unaligned = false,
> + .valid.min_access_size = 4,
> + .valid.max_access_size = 4,
> + .valid.unaligned = false,
> +};
Code totally untested =)
Regards,
Phil.
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