From 46d3fb634cb0e44c6cf0ed3a996d6996f3818c2d Mon Sep 17 00:00:00 2001 From: Andrey Smirnov Date: Thu, 15 Mar 2018 12:11:41 -0700 Subject: [PATCH] char: i.MX: Add support for "TX complete" interrupt Add support for "TX complete"/TXDC interrupt generate by real HW since it is needed to support guests other than Linux. Based on the patch by Bill Paul as found here: https://bugs.launchpad.net/qemu/+bug/1753314 Cc: qemu-devel@nongnu.org Cc: qemu-arm@nongnu.org Cc: Bill Paul Cc: Peter Maydell Signed-off-by: Bill Paul Signed-off-by: Andrey Smirnov Message-id: 20180315191141.6789-2-andrew.smirnov@gmail.com Reviewed-by: Peter Maydell Signed-off-by: Peter Maydell --- hw/char/imx_serial.c | 20 +++++++++++++++++--- include/hw/char/imx_serial.h | 3 +++ 2 files changed, 20 insertions(+), 3 deletions(-) diff --git a/hw/char/imx_serial.c b/hw/char/imx_serial.c index d1e8586280..1e5540472b 100644 --- a/hw/char/imx_serial.c +++ b/hw/char/imx_serial.c @@ -37,8 +37,8 @@ static const VMStateDescription vmstate_imx_serial = { .name = TYPE_IMX_SERIAL, - .version_id = 1, - .minimum_version_id = 1, + .version_id = 2, + .minimum_version_id = 2, .fields = (VMStateField[]) { VMSTATE_INT32(readbuff, IMXSerialState), VMSTATE_UINT32(usr1, IMXSerialState), @@ -50,6 +50,7 @@ static const VMStateDescription vmstate_imx_serial = { VMSTATE_UINT32(ubmr, IMXSerialState), VMSTATE_UINT32(ubrc, IMXSerialState), VMSTATE_UINT32(ucr3, IMXSerialState), + VMSTATE_UINT32(ucr4, IMXSerialState), VMSTATE_END_OF_LIST() }, }; @@ -71,6 +72,11 @@ static void imx_update(IMXSerialState *s) * unfortunately. */ mask = (s->ucr1 & UCR1_TXMPTYEN) ? USR2_TXFE : 0; + /* + * TCEN and TXDC are both bit 3 + */ + mask |= s->ucr4 & UCR4_TCEN; + usr2 = s->usr2 & mask; qemu_set_irq(s->irq, usr1 || usr2); @@ -163,6 +169,8 @@ static uint64_t imx_serial_read(void *opaque, hwaddr offset, return s->ucr3; case 0x23: /* UCR4 */ + return s->ucr4; + case 0x29: /* BRM Incremental */ return 0x0; /* TODO */ @@ -191,8 +199,10 @@ static void imx_serial_write(void *opaque, hwaddr offset, * qemu_chr_fe_write and background I/O callbacks */ qemu_chr_fe_write_all(&s->chr, &ch, 1); s->usr1 &= ~USR1_TRDY; + s->usr2 &= ~USR2_TXDC; imx_update(s); s->usr1 |= USR1_TRDY; + s->usr2 |= USR2_TXDC; imx_update(s); } break; @@ -265,8 +275,12 @@ static void imx_serial_write(void *opaque, hwaddr offset, s->ucr3 = value & 0xffff; break; - case 0x2d: /* UTS1 */ case 0x23: /* UCR4 */ + s->ucr4 = value & 0xffff; + imx_update(s); + break; + + case 0x2d: /* UTS1 */ qemu_log_mask(LOG_UNIMP, "[%s]%s: Unimplemented reg 0x%" HWADDR_PRIx "\n", TYPE_IMX_SERIAL, __func__, offset); /* TODO */ diff --git a/include/hw/char/imx_serial.h b/include/hw/char/imx_serial.h index baeec3183f..5b99cee7cf 100644 --- a/include/hw/char/imx_serial.h +++ b/include/hw/char/imx_serial.h @@ -67,6 +67,8 @@ #define UCR2_RXEN (1<<1) /* Receiver enable */ #define UCR2_SRST (1<<0) /* Reset complete */ +#define UCR4_TCEN BIT(3) /* TX complete interrupt enable */ + #define UTS1_TXEMPTY (1<<6) #define UTS1_RXEMPTY (1<<5) #define UTS1_TXFULL (1<<4) @@ -95,6 +97,7 @@ typedef struct IMXSerialState { uint32_t ubmr; uint32_t ubrc; uint32_t ucr3; + uint32_t ucr4; qemu_irq irq; CharBackend chr;