[PULL 20/20] hw/arm/exynos4210: Connect serial port DMA busy signals with pl330

[Peter Maydell]

From: Guenter Roeck <address@hidden>

The Exynos4210 serial driver uses an interrupt line to signal if receive
data is available. Connect that interrupt with the DMA controller's
'peripheral busy' gpio pin to stop the DMA if there is no more receive
data available. Without this patch, receive DMA runs wild and fills the
entire receive DMA buffer with invalid data.

Reviewed-by: Peter Maydell <address@hidden>
Signed-off-by: Guenter Roeck <address@hidden>
Message-id: address@hidden
Signed-off-by: Peter Maydell <address@hidden>
---
 hw/arm/exynos4210.c | 42 +++++++++++++++++++++++++++++-------------
 1 file changed, 29 insertions(+), 13 deletions(-)

diff --git a/hw/arm/exynos4210.c b/hw/arm/exynos4210.c
index 7701a3fa8bd..59a27bdd68f 100644
--- a/hw/arm/exynos4210.c
+++ b/hw/arm/exynos4210.c
@@ -166,8 +166,8 @@ static uint64_t exynos4210_calc_affinity(int cpu)
     return (0x9 << ARM_AFF1_SHIFT) | cpu;
 }
 
-static void pl330_create(uint32_t base, qemu_or_irq *orgate, qemu_irq irq,
-                         int nreq, int nevents, int width)
+static DeviceState *pl330_create(uint32_t base, qemu_or_irq *orgate,
+                                 qemu_irq irq, int nreq, int nevents, int 
width)
 {
     SysBusDevice *busdev;
     DeviceState *dev;
@@ -196,6 +196,7 @@ static void pl330_create(uint32_t base, qemu_or_irq 
*orgate, qemu_irq irq,
         sysbus_connect_irq(busdev, i, qdev_get_gpio_in(DEVICE(orgate), i));
     }
     qdev_connect_gpio_out(DEVICE(orgate), 0, irq);
+    return dev;
 }
 
 static void exynos4210_realize(DeviceState *socdev, Error **errp)
@@ -204,7 +205,7 @@ static void exynos4210_realize(DeviceState *socdev, Error 
**errp)
     MemoryRegion *system_mem = get_system_memory();
     qemu_irq gate_irq[EXYNOS4210_NCPUS][EXYNOS4210_IRQ_GATE_NINPUTS];
     SysBusDevice *busdev;
-    DeviceState *dev;
+    DeviceState *dev, *uart[4], *pl330[3];
     int i, n;
 
     for (n = 0; n < EXYNOS4210_NCPUS; n++) {
@@ -390,19 +391,19 @@ static void exynos4210_realize(DeviceState *socdev, Error 
**errp)
 
 
     /*** UARTs ***/
-    exynos4210_uart_create(EXYNOS4210_UART0_BASE_ADDR,
+    uart[0] = exynos4210_uart_create(EXYNOS4210_UART0_BASE_ADDR,
                            EXYNOS4210_UART0_FIFO_SIZE, 0, serial_hd(0),
                   s->irq_table[exynos4210_get_irq(EXYNOS4210_UART_INT_GRP, 
0)]);
 
-    exynos4210_uart_create(EXYNOS4210_UART1_BASE_ADDR,
+    uart[1] = exynos4210_uart_create(EXYNOS4210_UART1_BASE_ADDR,
                            EXYNOS4210_UART1_FIFO_SIZE, 1, serial_hd(1),
                   s->irq_table[exynos4210_get_irq(EXYNOS4210_UART_INT_GRP, 
1)]);
 
-    exynos4210_uart_create(EXYNOS4210_UART2_BASE_ADDR,
+    uart[2] = exynos4210_uart_create(EXYNOS4210_UART2_BASE_ADDR,
                            EXYNOS4210_UART2_FIFO_SIZE, 2, serial_hd(2),
                   s->irq_table[exynos4210_get_irq(EXYNOS4210_UART_INT_GRP, 
2)]);
 
-    exynos4210_uart_create(EXYNOS4210_UART3_BASE_ADDR,
+    uart[3] = exynos4210_uart_create(EXYNOS4210_UART3_BASE_ADDR,
                            EXYNOS4210_UART3_FIFO_SIZE, 3, serial_hd(3),
                   s->irq_table[exynos4210_get_irq(EXYNOS4210_UART_INT_GRP, 
3)]);
 
@@ -450,12 +451,27 @@ static void exynos4210_realize(DeviceState *socdev, Error 
**errp)
             s->irq_table[exynos4210_get_irq(28, 3)]);
 
     /*** DMA controllers ***/
-    pl330_create(EXYNOS4210_PL330_BASE0_ADDR, &s->pl330_irq_orgate[0],
-                 s->irq_table[exynos4210_get_irq(21, 0)], 32, 32, 32);
-    pl330_create(EXYNOS4210_PL330_BASE1_ADDR, &s->pl330_irq_orgate[1],
-                 s->irq_table[exynos4210_get_irq(21, 1)], 32, 32, 32);
-    pl330_create(EXYNOS4210_PL330_BASE2_ADDR, &s->pl330_irq_orgate[2],
-                 s->irq_table[exynos4210_get_irq(20, 1)], 1, 31, 64);
+    pl330[0] = pl330_create(EXYNOS4210_PL330_BASE0_ADDR,
+                            &s->pl330_irq_orgate[0],
+                            s->irq_table[exynos4210_get_irq(21, 0)],
+                            32, 32, 32);
+    pl330[1] = pl330_create(EXYNOS4210_PL330_BASE1_ADDR,
+                            &s->pl330_irq_orgate[1],
+                            s->irq_table[exynos4210_get_irq(21, 1)],
+                            32, 32, 32);
+    pl330[2] = pl330_create(EXYNOS4210_PL330_BASE2_ADDR,
+                            &s->pl330_irq_orgate[2],
+                            s->irq_table[exynos4210_get_irq(20, 1)],
+                            1, 31, 64);
+
+    sysbus_connect_irq(SYS_BUS_DEVICE(uart[0]), 1,
+                       qdev_get_gpio_in(pl330[0], 15));
+    sysbus_connect_irq(SYS_BUS_DEVICE(uart[1]), 1,
+                       qdev_get_gpio_in(pl330[1], 15));
+    sysbus_connect_irq(SYS_BUS_DEVICE(uart[2]), 1,
+                       qdev_get_gpio_in(pl330[0], 17));
+    sysbus_connect_irq(SYS_BUS_DEVICE(uart[3]), 1,
+                       qdev_get_gpio_in(pl330[1], 17));
 }
 
 static void exynos4210_init(Object *obj)
-- 
2.20.1