[PATCH v3 0/3] Connect STM32L4x5 USART devices to the EXTI

[PATCH v3 0/3] Connect STM32L4x5 USART devices to the EXTI

[Inès Varhol]

STM32L4x5 EXTI was handling only configurable interrupts
(such as those coming from STM32L4x5 SYSCFG which was the
only device connected to the EXTI).
This patch adds support for direct line interrupts and
connects the existing STM32L4x5 USART devices to the EXTI.
The patch also corrects the handling of configurable line
interrupts in the EXTI.

Changes from v2 (2nd commit):
- The 2nd commit was split, part of the changes went in
another patch correcting EXTI configurable interrupts.
Stayed in the commit only changes relevant to direct interrupts.

Changes from v1 (2nd commit):
- add STM32L4x5 EXTI status fields `irq_levels` to track
configurable irq levels and do edge detection
- use `qemu_set_irq` instead of qemu_irq_raise/lower

Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>

Inès Varhol (3):
  hw/misc: In STM32L4x5 EXTI, consolidate 2 constants
  hw/misc: In STM32L4x5 EXTI, handle direct interrupts
  hw/arm: In STM32L4x5 SOC, connect USART devices to EXTI

 include/hw/misc/stm32l4x5_exti.h |  4 ++--
 hw/arm/stm32l4x5_soc.c           | 24 +++++++++++-------------
 hw/misc/stm32l4x5_exti.c         | 13 +++++++++----
 3 files changed, 22 insertions(+), 19 deletions(-)

-- 
2.43.2

[PATCH v3 1/3] hw/misc: In STM32L4x5 EXTI, consolidate 2 constants

[Inès Varhol]

Up until now, the EXTI implementation had 16 inbound GPIOs connected to
the 16 outbound GPIOs of STM32L4x5 SYSCFG.
The EXTI actually handles 40 lines (namely 5 from STM32L4x5 USART
devices which are already implemented in QEMU).
In order to connect USART devices to EXTI, this commit consolidates
constants `EXTI_NUM_INTERRUPT_OUT_LINES` (40) and
`EXTI_NUM_GPIO_EVENT_IN_LINES` (16) into `EXTI_NUM_LINES` (40).

Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
---
 include/hw/misc/stm32l4x5_exti.h | 4 ++--
 hw/misc/stm32l4x5_exti.c         | 6 ++----
 2 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/include/hw/misc/stm32l4x5_exti.h b/include/hw/misc/stm32l4x5_exti.h
index 55f763fa37..62f79362f2 100644
--- a/include/hw/misc/stm32l4x5_exti.h
+++ b/include/hw/misc/stm32l4x5_exti.h
@@ -30,7 +30,7 @@
 #define TYPE_STM32L4X5_EXTI "stm32l4x5-exti"
 OBJECT_DECLARE_SIMPLE_TYPE(Stm32l4x5ExtiState, STM32L4X5_EXTI)
 
-#define EXTI_NUM_INTERRUPT_OUT_LINES 40
+#define EXTI_NUM_LINES 40
 #define EXTI_NUM_REGISTER 2
 
 struct Stm32l4x5ExtiState {
@@ -47,7 +47,7 @@ struct Stm32l4x5ExtiState {
 
     /* used for edge detection */
     uint32_t irq_levels[EXTI_NUM_REGISTER];
-    qemu_irq irq[EXTI_NUM_INTERRUPT_OUT_LINES];
+    qemu_irq irq[EXTI_NUM_LINES];
 };
 
 #endif
diff --git a/hw/misc/stm32l4x5_exti.c b/hw/misc/stm32l4x5_exti.c
index 6a2ec62d78..b9a69a69f6 100644
--- a/hw/misc/stm32l4x5_exti.c
+++ b/hw/misc/stm32l4x5_exti.c
@@ -42,7 +42,6 @@
 #define EXTI_SWIER2 0x30
 #define EXTI_PR2    0x34
 
-#define EXTI_NUM_GPIO_EVENT_IN_LINES 16
 #define EXTI_MAX_IRQ_PER_BANK 32
 #define EXTI_IRQS_BANK0  32
 #define EXTI_IRQS_BANK1  8
@@ -238,7 +237,7 @@ static void stm32l4x5_exti_init(Object *obj)
 {
     Stm32l4x5ExtiState *s = STM32L4X5_EXTI(obj);
 
-    for (size_t i = 0; i < EXTI_NUM_INTERRUPT_OUT_LINES; i++) {
+    for (size_t i = 0; i < EXTI_NUM_LINES; i++) {
         sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq[i]);
     }
 
@@ -246,8 +245,7 @@ static void stm32l4x5_exti_init(Object *obj)
                           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);
+    qdev_init_gpio_in(DEVICE(obj), stm32l4x5_exti_set_irq, EXTI_NUM_LINES);
 }
 
 static const VMStateDescription vmstate_stm32l4x5_exti = {
-- 
2.43.2

[PATCH v3 2/3] hw/misc: In STM32L4x5 EXTI, handle direct interrupts

[Inès Varhol]

The previous implementation for EXTI interrupts only handled
"configurable" interrupts, like those originating from STM32L4x5 SYSCFG
(the only device currently connected to the EXTI up until now).

In order to connect STM32L4x5 USART to the EXTI, this commit adds
handling for direct interrupts (interrupts without configurable edge).

Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>
---
 hw/misc/stm32l4x5_exti.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/hw/misc/stm32l4x5_exti.c b/hw/misc/stm32l4x5_exti.c
index b9a69a69f6..e281841dcf 100644
--- a/hw/misc/stm32l4x5_exti.c
+++ b/hw/misc/stm32l4x5_exti.c
@@ -113,6 +113,13 @@ static void stm32l4x5_exti_set_irq(void *opaque, int irq, int level)
         return;
     }
 
+    /* In case of a direct line interrupt */
+    if (extract32(exti_romask[bank], irq, 1)) {
+        qemu_set_irq(s->irq[oirq], level);
+        return;
+    }
+
+    /* In case of a configurable interrupt */
     if ((level && extract32(s->rtsr[bank], irq, 1)) ||
         (!level && extract32(s->ftsr[bank], irq, 1))) {
 
-- 
2.43.2

[PATCH v3 3/3] hw/arm: In STM32L4x5 SOC, connect USART devices to EXTI

[Inès Varhol]

The USART devices were previously connecting their outbound IRQs
directly to the CPU because the EXTI wasn't handling direct lines
interrupts.
Now the USART connects to the EXTI inbound GPIOs, and the EXTI connects
its IRQs to the CPU.
The existing QTest for the USART (tests/qtest/stm32l4x5_usart-test.c)
checks that USART1_IRQ in the CPU is pending when expected so it
confirms that the connection through the EXTI still works.

Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
---
 hw/arm/stm32l4x5_soc.c | 24 +++++++++++-------------
 1 file changed, 11 insertions(+), 13 deletions(-)

diff --git a/hw/arm/stm32l4x5_soc.c b/hw/arm/stm32l4x5_soc.c
index 38f7a2d5d9..fac83d349c 100644
--- a/hw/arm/stm32l4x5_soc.c
+++ b/hw/arm/stm32l4x5_soc.c
@@ -81,6 +81,10 @@ static const int exti_irq[NUM_EXTI_IRQ] = {
 #define RCC_BASE_ADDRESS 0x40021000
 #define RCC_IRQ 5
 
+#define EXTI_USART1_IRQ 26
+#define EXTI_UART4_IRQ 29
+#define EXTI_LPUART1_IRQ 31
+
 static const int exti_or_gates_out[NUM_EXTI_OR_GATES] = {
     23, 40, 63, 1,
 };
@@ -129,10 +133,6 @@ static const hwaddr uart_addr[] = {
 
 #define LPUART_BASE_ADDRESS 0x40008000
 
-static const int usart_irq[] = { 37, 38, 39 };
-static const int uart_irq[] = { 52, 53 };
-#define LPUART_IRQ 70
-
 static void stm32l4x5_soc_initfn(Object *obj)
 {
     Stm32l4x5SocState *s = STM32L4X5_SOC(obj);
@@ -297,6 +297,7 @@ static void stm32l4x5_soc_realize(DeviceState *dev_soc, Error **errp)
         }
     }
 
+    /* Connect SYSCFG to EXTI */
     for (unsigned i = 0; i < GPIO_NUM_PINS; i++) {
         qdev_connect_gpio_out(DEVICE(&s->syscfg), i,
                               qdev_get_gpio_in(DEVICE(&s->exti), i));
@@ -322,15 +323,10 @@ static void stm32l4x5_soc_realize(DeviceState *dev_soc, Error **errp)
             return;
         }
         sysbus_mmio_map(busdev, 0, usart_addr[i]);
-        sysbus_connect_irq(busdev, 0, qdev_get_gpio_in(armv7m, usart_irq[i]));
+        sysbus_connect_irq(busdev, 0, qdev_get_gpio_in(DEVICE(&s->exti),
+                                                       EXTI_USART1_IRQ + i));
     }
 
-    /*
-     * TODO: Connect the USARTs, UARTs and LPUART to the EXTI once the EXTI
-     * can handle other gpio-in than the gpios. (e.g. Direct Lines for the
-     * usarts)
-     */
-
     /* UART devices */
     for (int i = 0; i < STM_NUM_UARTS; i++) {
         g_autofree char *name = g_strdup_printf("uart%d-out", STM_NUM_USARTS + i + 1);
@@ -343,7 +339,8 @@ static void stm32l4x5_soc_realize(DeviceState *dev_soc, Error **errp)
             return;
         }
         sysbus_mmio_map(busdev, 0, uart_addr[i]);
-        sysbus_connect_irq(busdev, 0, qdev_get_gpio_in(armv7m, uart_irq[i]));
+        sysbus_connect_irq(busdev, 0, qdev_get_gpio_in(DEVICE(&s->exti),
+                                                       EXTI_UART4_IRQ + i));
     }
 
     /* LPUART device*/
@@ -356,7 +353,8 @@ static void stm32l4x5_soc_realize(DeviceState *dev_soc, Error **errp)
         return;
     }
     sysbus_mmio_map(busdev, 0, LPUART_BASE_ADDRESS);
-    sysbus_connect_irq(busdev, 0, qdev_get_gpio_in(armv7m, LPUART_IRQ));
+    sysbus_connect_irq(busdev, 0, qdev_get_gpio_in(DEVICE(&s->exti),
+                                                   EXTI_LPUART1_IRQ));
 
     /* APB1 BUS */
     create_unimplemented_device("TIM2",      0x40000000, 0x400);
-- 
2.43.2

Re: [PATCH v3 0/3] Connect STM32L4x5 USART devices to the EXTI

[Peter Maydell]

On Sun, 7 Jul 2024 at 09:59, Inès Varhol <ines.varhol@telecom-paris.fr> wrote:
>
> STM32L4x5 EXTI was handling only configurable interrupts
> (such as those coming from STM32L4x5 SYSCFG which was the
> only device connected to the EXTI).
> This patch adds support for direct line interrupts and
> connects the existing STM32L4x5 USART devices to the EXTI.
> The patch also corrects the handling of configurable line
> interrupts in the EXTI.
>
> Changes from v2 (2nd commit):
> - The 2nd commit was split, part of the changes went in
> another patch correcting EXTI configurable interrupts.
> Stayed in the commit only changes relevant to direct interrupts.
>
> Changes from v1 (2nd commit):
> - add STM32L4x5 EXTI status fields `irq_levels` to track
> configurable irq levels and do edge detection
> - use `qemu_set_irq` instead of qemu_irq_raise/lower
>
> Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>



Applied to target-arm.next, thanks.

-- PMM