diff options
Diffstat (limited to 'hw/char/stm32f2xx_usart.c')
| -rw-r--r-- | hw/char/stm32f2xx_usart.c | 32 |
1 files changed, 19 insertions, 13 deletions
diff --git a/hw/char/stm32f2xx_usart.c b/hw/char/stm32f2xx_usart.c index 8df0832424..8753afeb2b 100644 --- a/hw/char/stm32f2xx_usart.c +++ b/hw/char/stm32f2xx_usart.c @@ -53,6 +53,17 @@ static int stm32f2xx_usart_can_receive(void *opaque) return 0; } +static void stm32f2xx_update_irq(STM32F2XXUsartState *s) +{ + uint32_t mask = s->usart_sr & s->usart_cr1; + + if (mask & (USART_SR_TXE | USART_SR_TC | USART_SR_RXNE)) { + qemu_set_irq(s->irq, 1); + } else { + qemu_set_irq(s->irq, 0); + } +} + static void stm32f2xx_usart_receive(void *opaque, const uint8_t *buf, int size) { STM32F2XXUsartState *s = opaque; @@ -66,9 +77,7 @@ static void stm32f2xx_usart_receive(void *opaque, const uint8_t *buf, int size) s->usart_dr = *buf; s->usart_sr |= USART_SR_RXNE; - if (s->usart_cr1 & USART_CR1_RXNEIE) { - qemu_set_irq(s->irq, 1); - } + stm32f2xx_update_irq(s); DB_PRINT("Receiving: %c\n", s->usart_dr); } @@ -85,7 +94,7 @@ static void stm32f2xx_usart_reset(DeviceState *dev) s->usart_cr3 = 0x00000000; s->usart_gtpr = 0x00000000; - qemu_set_irq(s->irq, 0); + stm32f2xx_update_irq(s); } static uint64_t stm32f2xx_usart_read(void *opaque, hwaddr addr, @@ -103,10 +112,11 @@ static uint64_t stm32f2xx_usart_read(void *opaque, hwaddr addr, return retvalue; case USART_DR: DB_PRINT("Value: 0x%" PRIx32 ", %c\n", s->usart_dr, (char) s->usart_dr); + retvalue = s->usart_dr & 0x3FF; s->usart_sr &= ~USART_SR_RXNE; qemu_chr_fe_accept_input(&s->chr); - qemu_set_irq(s->irq, 0); - return s->usart_dr & 0x3FF; + stm32f2xx_update_irq(s); + return retvalue; case USART_BRR: return s->usart_brr; case USART_CR1: @@ -144,9 +154,7 @@ static void stm32f2xx_usart_write(void *opaque, hwaddr addr, } else { s->usart_sr &= value; } - if (!(s->usart_sr & USART_SR_RXNE)) { - qemu_set_irq(s->irq, 0); - } + stm32f2xx_update_irq(s); return; case USART_DR: if (value < 0xF000) { @@ -160,6 +168,7 @@ static void stm32f2xx_usart_write(void *opaque, hwaddr addr, clear TC by writing 0 to the SR register, so set it again on each write. */ s->usart_sr |= USART_SR_TC; + stm32f2xx_update_irq(s); } return; case USART_BRR: @@ -167,10 +176,7 @@ static void stm32f2xx_usart_write(void *opaque, hwaddr addr, return; case USART_CR1: s->usart_cr1 = value; - if (s->usart_cr1 & USART_CR1_RXNEIE && - s->usart_sr & USART_SR_RXNE) { - qemu_set_irq(s->irq, 1); - } + stm32f2xx_update_irq(s); return; case USART_CR2: s->usart_cr2 = value; |