pc_com: handle tx differently

This commit is contained in:
Matheus
2025-08-16 00:52:17 -03:00
parent e916294427
commit c10bebb9ef
+6 -31
View File
@@ -61,11 +61,7 @@ typedef struct {
int io_base;
uacpi_resource_irq irq;
ringbuffer_t tx_ringbuffer;
spinlock_t tx_spinlock; // locked in IPL_SERIAL
ringbuffer_t rx_ringbuffer;
thread_t *handler_thread;
semaphore_t rx_semaphore;
@@ -102,12 +98,6 @@ static bool can_transmit(pc_com_t *pc_com) {
return read_port(pc_com, PORT_LINE_STATUS) & LINE_STATUS_TX_BUFFER_EMPTY;
}
static void transmit_data(pc_com_t *pc_com) {
char c;
ringbuffer_read(&pc_com->tx_ringbuffer, &c, 1);
write_port(pc_com, PORT_TX, c);
}
static void set_irqs(pc_com_t *pc_com, int irqs) {
write_port(pc_com, PORT_INTERRUPT_ENABLE, irqs);
}
@@ -185,33 +175,20 @@ static void handler_thread(void) {
static size_t write_tty(void *internal, char *str, size_t size) {
pc_com_t *pc_com = internal;
long ipl = spinlock_acquire_raise_ipl(&pc_com->tx_spinlock, IPL_SERIAL);
for (int i = 0; i < size; ++i) {
while (!can_transmit(pc_com));
write_port(pc_com, PORT_TX, str[i]);
}
size_t written = ringbuffer_write(&pc_com->tx_ringbuffer, str, size);
if (can_transmit(pc_com))
transmit_data(pc_com);
spinlock_release_lower_ipl(&pc_com->tx_spinlock, ipl);
return written;
return size;
}
// TODO enqueue dpc and call tty_process directly from it once it is safe to be called from an interrupt context
static void irq(isr_t *self, context_t *) {
pc_com_t *pc_com = self->priv;
int interrupt_status = read_port(pc_com, PORT_INTERRUPT_ID) & 0x0e;
// check if there is data to be received
process_data(pc_com);
// check if there is data to be transmitted and tx buffer is empty
spinlock_acquire(&pc_com->tx_spinlock);
if (((interrupt_status == INTERRUPT_STATUS_TX_EMPTY) || can_transmit(pc_com)) && RINGBUFFER_DATACOUNT(&pc_com->tx_ringbuffer))
transmit_data(pc_com);
spinlock_release(&pc_com->tx_spinlock);
}
static uacpi_iteration_decision set_com_resource(void *user, uacpi_resource *res) {
@@ -237,12 +214,10 @@ static uacpi_iteration_decision init_com(void *, uacpi_namespace_node *node, uns
pc_com_t *pc_com = alloc(sizeof(pc_com_t));
__assert(pc_com);
__assert(ringbuffer_init(&pc_com->tx_ringbuffer, 1000) == 0);
__assert(ringbuffer_init(&pc_com->rx_ringbuffer, 1000) == 0);
pc_com->id = pc_com_id++;
SEMAPHORE_INIT(&pc_com->rx_semaphore, 0);
SPINLOCK_INIT(pc_com->tx_spinlock);
// get io port and gsi
uacpi_status ret = uacpi_get_current_resources(node, &res);
@@ -268,7 +243,7 @@ static uacpi_iteration_decision init_com(void *, uacpi_namespace_node *node, uns
set_irqs(pc_com, INTERRUPT_ENABLE_NONE);
set_baud_divisor(pc_com, 3);
write_port(pc_com, PORT_LINE_CONTROL, LINE_CONTROL_WORD_LENGTH_8_BITS);
set_irqs(pc_com, INTERRUPT_ENABLE_DATA_AVAILABLE | INTERRUPT_ENABLE_TX_EMPTY);
set_irqs(pc_com, INTERRUPT_ENABLE_DATA_AVAILABLE);
write_port(pc_com, PORT_MODEM_CONTROL,
MODEM_CONTROL_DATA_TERMINAL_READY | MODEM_CONTROL_REQUEST_TO_SEND | MODEM_CONTROL_AUX_1 | MODEM_CONTROL_AUX_2);