UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

serial: pch: decomission pch_uart_hal_write() 

It's horrid and if we inline it into callers, we can get rid of a lot of
sugar around.

So:
* x_char handling becomes a single iowrite8.
* xmit->buf handling is a single loop simply writing characters one by
  one directly from the buf instead of complex cnt_to_end computations.
  Until the buf is empty or fifo size is reached.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220503080808.28332-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jiri Slaby 2022-05-03 10:08:04 +02:00 committed by Greg Kroah-Hartman
parent d9f3af4fbb
commit fcfb1c3982
1 changed files with 13 additions and 33 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

46
drivers/tty/serial/pch_uart.c
View File

@ -550,18 +550,6 @@ static u8 pch_uart_hal_get_modem(struct eg20t_port *priv)
return (u8)msr;
}
static void pch_uart_hal_write(struct eg20t_port *priv,
const unsigned char *buf, int tx_size)
{
int i;
unsigned int thr;
for (i = 0; i < tx_size;) {
thr = buf[i++];
iowrite8(thr, priv->membase + PCH_UART_THR);
}
}
static int pch_uart_hal_read(struct eg20t_port *priv, unsigned char *buf,
int rx_size)
{
@ -769,23 +757,21 @@ static void pch_dma_tx_complete(void *arg)
pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_TX_INT);
}
static int pop_tx(struct eg20t_port *priv, int size)
static bool pop_tx(struct eg20t_port *priv, unsigned int size)
{
int count = 0;
unsigned int count = 0;
struct uart_port *port = &priv->port;
struct circ_buf *xmit = &port->state->xmit;
if (uart_tx_stopped(port) || uart_circ_empty(xmit))
if (uart_tx_stopped(port))
goto pop_tx_end;
do {
int cnt_to_end =
CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
int sz = min(size - count, cnt_to_end);
pch_uart_hal_write(priv, &xmit->buf[xmit->tail], sz);
xmit->tail = (xmit->tail + sz) & (UART_XMIT_SIZE - 1);
count += sz;
} while (!uart_circ_empty(xmit) && count < size);
while (!uart_circ_empty(xmit) && count < size) {
iowrite8(xmit->buf[xmit->tail], priv->membase + PCH_UART_THR);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
count++;
}
pop_tx_end:
dev_dbg(priv->port.dev, "%d characters. Remained %d characters.(%lu)\n",
@ -859,7 +845,6 @@ static unsigned int handle_tx(struct eg20t_port *priv)
struct uart_port *port = &priv->port;
struct circ_buf *xmit = &port->state->xmit;
int fifo_size;
int tx_size;
int size;
int tx_empty;
@ -874,7 +859,7 @@ static unsigned int handle_tx(struct eg20t_port *priv)
fifo_size = max(priv->fifo_size, 1);
tx_empty = 1;
if (port->x_char) {
pch_uart_hal_write(priv, &port->x_char, 1);
iowrite8(port->x_char, priv->membase + PCH_UART_THR);
port->icount.tx++;
port->x_char = 0;
tx_empty = 0;
@ -884,13 +869,8 @@ static unsigned int handle_tx(struct eg20t_port *priv)
size = min(xmit->head - xmit->tail, fifo_size);
if (size < 0)
size = fifo_size;
if (size) {
tx_size = pop_tx(priv, size);
if (tx_size > 0) {
port->icount.tx += tx_size;
tx_empty = 0;
}
}
if (size && pop_tx(priv, size))
tx_empty = 0;
priv->tx_empty = tx_empty;
@ -935,7 +915,7 @@ static unsigned int dma_handle_tx(struct eg20t_port *priv)
fifo_size = max(priv->fifo_size, 1);
if (port->x_char) {
pch_uart_hal_write(priv, &port->x_char, 1);
iowrite8(port->x_char, priv->membase + PCH_UART_THR);
port->icount.tx++;
port->x_char = 0;
fifo_size--;