HV: vuart: refine vuart read/write

The vuart_read()/vuart_write() are coupled with PIO vuart type. Move
the non-type related code into vuart_read_reg()/vuart_write_reg(), so
that we can re-use them to handle MMIO request of pci-vuart type.

Tracked-On: #5394
Signed-off-by: Tao Yuhong <yuhong.tao@intel.com>
Reviewed-by: Wang, Yu1 <yu1.wang@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
This commit is contained in:
Tao Yuhong 2020-10-09 06:28:13 -04:00 committed by wenlingz
parent 8e545734d4
commit 6ed7b8767c
2 changed files with 123 additions and 102 deletions

View File

@ -362,6 +362,30 @@ static void write_reg(struct acrn_vuart *vu, uint16_t reg, uint8_t value_u8)
release_vuart_lock(vu, rflags);
}
/*
* @pre: vu != NULL
*/
void vuart_write_reg(struct acrn_vuart *vu, uint16_t offset, uint8_t value_u8)
{
struct acrn_vuart *target_vu = NULL;
uint64_t rflags;
target_vu = vu->target_vu;
if (((vu->mcr & MCR_LOOPBACK) == 0U) && ((vu->lcr & LCR_DLAB) == 0U)
&& (offset == UART16550_THR) && (target_vu != NULL)) {
if (!send_to_target(target_vu, value_u8)) {
/* FIFO is not full, raise THRE interrupt */
obtain_vuart_lock(vu, rflags);
vu->thre_int_pending = true;
vuart_toggle_intr(vu);
release_vuart_lock(vu, rflags);
}
} else {
write_reg(vu, offset, value_u8);
}
}
/**
* @pre vcpu != NULL
* @pre vcpu->vm != NULL
@ -372,25 +396,10 @@ static bool vuart_write(struct acrn_vcpu *vcpu, uint16_t offset_arg,
uint16_t offset = offset_arg;
struct acrn_vuart *vu = find_vuart_by_port(vcpu->vm, offset);
uint8_t value_u8 = (uint8_t)value;
struct acrn_vuart *target_vu = NULL;
uint64_t rflags;
if (vu != NULL) {
offset -= vu->port_base;
target_vu = vu->target_vu;
if (((vu->mcr & MCR_LOOPBACK) == 0U) && ((vu->lcr & LCR_DLAB) == 0U)
&& (offset == UART16550_THR) && (target_vu != NULL)) {
if (!send_to_target(target_vu, value_u8)) {
/* FIFO is not full, raise THRE interrupt */
obtain_vuart_lock(vu, rflags);
vu->thre_int_pending = true;
vuart_toggle_intr(vu);
release_vuart_lock(vu, rflags);
}
} else {
write_reg(vu, offset, value_u8);
}
vuart_write_reg(vu, offset, value_u8);
}
return true;
}
@ -411,6 +420,100 @@ static void notify_target(const struct acrn_vuart *vu)
}
}
/**
* @pre vu != NULL
*/
uint8_t vuart_read_reg(struct acrn_vuart *vu, uint16_t offset)
{
struct acrn_vuart *t_vu;
uint8_t iir, reg = 0U, intr_reason;
uint64_t rflags;
t_vu = vu->target_vu;
obtain_vuart_lock(vu, rflags);
/*
* Take care of the special case DLAB accesses first
*/
if ((vu->lcr & LCR_DLAB) != 0U) {
if (offset == UART16550_DLL) {
reg = vu->dll;
} else if (offset == UART16550_DLM) {
reg = vu->dlh;
} else {
reg = 0U;
}
} else {
switch (offset) {
case UART16550_RBR:
vu->lsr &= ~LSR_OE;
reg = (uint8_t)fifo_getchar(&vu->rxfifo);
break;
case UART16550_IER:
reg = vu->ier;
break;
case UART16550_IIR:
iir = ((vu->fcr & FCR_FIFOE) != 0U) ? IIR_FIFO_MASK : 0U;
intr_reason = vuart_intr_reason(vu);
/*
* Deal with side effects of reading the IIR register
*/
if (intr_reason == IIR_TXRDY) {
vu->thre_int_pending = false;
}
iir |= intr_reason;
reg = iir;
break;
case UART16550_LCR:
reg = vu->lcr;
break;
case UART16550_MCR:
reg = vu->mcr;
break;
case UART16550_LSR:
if (t_vu != NULL) {
if (!fifo_isfull(&t_vu->rxfifo)) {
vu->lsr |= LSR_TEMT | LSR_THRE;
}
} else {
vu->lsr |= LSR_TEMT | LSR_THRE;
}
/* Check for new receive data */
if (fifo_numchars(&vu->rxfifo) > 0U) {
vu->lsr |= LSR_DR;
} else {
vu->lsr &= ~LSR_DR;
}
reg = vu->lsr;
/* The LSR_OE bit is cleared on LSR read */
vu->lsr &= ~LSR_OE;
break;
case UART16550_MSR:
/*
* MSR delta bits are cleared on read
*/
reg = vu->msr;
vu->msr &= ~MSR_DELTA_MASK;
break;
case UART16550_SCR:
reg = vu->scr;
break;
default:
reg = 0xFFU;
break;
}
}
vuart_toggle_intr(vu);
release_vuart_lock(vu, rflags);
/* For commnunication vuart, when the data in FIFO is read out, should
* notify the target vuart to send more data. */
if (offset == UART16550_RBR) {
notify_target(vu);
}
return reg;
}
/**
* @pre vcpu != NULL
* @pre vcpu->vm != NULL
@ -418,97 +521,12 @@ static void notify_target(const struct acrn_vuart *vu)
static bool vuart_read(struct acrn_vcpu *vcpu, uint16_t offset_arg, __unused size_t width)
{
uint16_t offset = offset_arg;
uint8_t iir, reg, intr_reason;
struct acrn_vuart *vu = find_vuart_by_port(vcpu->vm, offset);
struct acrn_vuart *t_vu;
struct pio_request *pio_req = &vcpu->req.reqs.pio;
uint64_t rflags;
if (vu != NULL) {
t_vu = vu->target_vu;
offset -= vu->port_base;
obtain_vuart_lock(vu, rflags);
/*
* Take care of the special case DLAB accesses first
*/
if ((vu->lcr & LCR_DLAB) != 0U) {
if (offset == UART16550_DLL) {
reg = vu->dll;
} else if (offset == UART16550_DLM) {
reg = vu->dlh;
} else {
reg = 0U;
}
} else {
switch (offset) {
case UART16550_RBR:
vu->lsr &= ~LSR_OE;
reg = (uint8_t)fifo_getchar(&vu->rxfifo);
break;
case UART16550_IER:
reg = vu->ier;
break;
case UART16550_IIR:
iir = ((vu->fcr & FCR_FIFOE) != 0U) ? IIR_FIFO_MASK : 0U;
intr_reason = vuart_intr_reason(vu);
/*
* Deal with side effects of reading the IIR register
*/
if (intr_reason == IIR_TXRDY) {
vu->thre_int_pending = false;
}
iir |= intr_reason;
reg = iir;
break;
case UART16550_LCR:
reg = vu->lcr;
break;
case UART16550_MCR:
reg = vu->mcr;
break;
case UART16550_LSR:
if (t_vu != NULL) {
if (!fifo_isfull(&t_vu->rxfifo)) {
vu->lsr |= LSR_TEMT | LSR_THRE;
}
} else {
vu->lsr |= LSR_TEMT | LSR_THRE;
}
/* Check for new receive data */
if (fifo_numchars(&vu->rxfifo) > 0U) {
vu->lsr |= LSR_DR;
} else {
vu->lsr &= ~LSR_DR;
}
reg = vu->lsr;
/* The LSR_OE bit is cleared on LSR read */
vu->lsr &= ~LSR_OE;
break;
case UART16550_MSR:
/*
* MSR delta bits are cleared on read
*/
reg = vu->msr;
vu->msr &= ~MSR_DELTA_MASK;
break;
case UART16550_SCR:
reg = vu->scr;
break;
default:
reg = 0xFFU;
break;
}
}
vuart_toggle_intr(vu);
pio_req->value = (uint32_t)reg;
release_vuart_lock(vu, rflags);
}
/* For commnunication vuart, when the data in FIFO is read out, should
* notify the target vuart to send more data. */
if (offset == UART16550_RBR) {
notify_target(vu);
pio_req->value = (uint32_t)vuart_read_reg(vu, offset);
}
return true;

View File

@ -89,4 +89,7 @@ char vuart_getchar(struct acrn_vuart *vu);
void vuart_toggle_intr(const struct acrn_vuart *vu);
bool is_vuart_intx(const struct acrn_vm *vm, uint32_t intx_gsi);
uint8_t vuart_read_reg(struct acrn_vuart *vu, uint16_t offset);
void vuart_write_reg(struct acrn_vuart *vu, uint16_t offset, uint8_t value);
#endif /* VUART_H */