lkml.org 
[lkml]   [2020]   [Jun]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/2] serial: qcom_geni_serial: Always use 4 bytes per TX FIFO word
Date
The geni serial driver had a rule that we'd only use 1 byte per FIFO
word for the TX FIFO if we were being used for the serial console.
This is ugly and a bit of a pain. It's not too hard to fix, so fix
it.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
---

drivers/tty/serial/qcom_geni_serial.c | 57 +++++++++++++++++----------
1 file changed, 37 insertions(+), 20 deletions(-)

diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index 4610e391e886..583d903321b5 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -103,12 +103,18 @@
#define DEFAULT_IO_MACRO_IO2_IO3_MASK GENMASK(15, 4)
#define IO_MACRO_IO2_IO3_SWAP 0x4640

+/* We always configure 4 bytes per FIFO word */
+#define BYTES_PER_FIFO_WORD 4
+
struct qcom_geni_private_data {
/* NOTE: earlycon port will have NULL here */
struct uart_driver *drv;

u32 poll_cached_bytes;
unsigned int poll_cached_bytes_cnt;
+
+ u32 write_cached_bytes;
+ unsigned int write_cached_bytes_cnt;
};

struct qcom_geni_serial_port {
@@ -121,8 +127,6 @@ struct qcom_geni_serial_port {
bool setup;
int (*handle_rx)(struct uart_port *uport, u32 bytes, bool drop);
unsigned int baud;
- unsigned int tx_bytes_pw;
- unsigned int rx_bytes_pw;
void *rx_fifo;
u32 loopback;
bool brk;
@@ -390,13 +394,25 @@ static void qcom_geni_serial_poll_put_char(struct uart_port *uport,
#ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
static void qcom_geni_serial_wr_char(struct uart_port *uport, int ch)
{
- writel(ch, uport->membase + SE_GENI_TX_FIFOn);
+ struct qcom_geni_private_data *private_data = uport->private_data;
+
+ private_data->write_cached_bytes =
+ (private_data->write_cached_bytes >> 8) | (ch << 24);
+ private_data->write_cached_bytes_cnt++;
+
+ if (private_data->write_cached_bytes_cnt == BYTES_PER_FIFO_WORD) {
+ writel(private_data->write_cached_bytes,
+ uport->membase + SE_GENI_TX_FIFOn);
+ private_data->write_cached_bytes_cnt = 0;
+ }
}

static void
__qcom_geni_serial_console_write(struct uart_port *uport, const char *s,
unsigned int count)
{
+ struct qcom_geni_private_data *private_data = uport->private_data;
+
int i;
u32 bytes_to_send = count;

@@ -431,6 +447,15 @@ __qcom_geni_serial_console_write(struct uart_port *uport, const char *s,
SE_GENI_M_IRQ_CLEAR);
i += chars_to_write;
}
+
+ if (private_data->write_cached_bytes_cnt) {
+ private_data->write_cached_bytes >>= BITS_PER_BYTE *
+ (BYTES_PER_FIFO_WORD - private_data->write_cached_bytes_cnt);
+ writel(private_data->write_cached_bytes,
+ uport->membase + SE_GENI_TX_FIFOn);
+ private_data->write_cached_bytes_cnt = 0;
+ }
+
qcom_geni_serial_poll_tx_done(uport);
}

@@ -503,7 +528,7 @@ static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
tport = &uport->state->port;
for (i = 0; i < bytes; ) {
int c;
- int chunk = min_t(int, bytes - i, port->rx_bytes_pw);
+ int chunk = min_t(int, bytes - i, BYTES_PER_FIFO_WORD);

ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, buf, 1);
i += chunk;
@@ -683,11 +708,11 @@ static void qcom_geni_serial_handle_rx(struct uart_port *uport, bool drop)

if (!word_cnt)
return;
- total_bytes = port->rx_bytes_pw * (word_cnt - 1);
+ total_bytes = BYTES_PER_FIFO_WORD * (word_cnt - 1);
if (last_word_partial && last_word_byte_cnt)
total_bytes += last_word_byte_cnt;
else
- total_bytes += port->rx_bytes_pw;
+ total_bytes += BYTES_PER_FIFO_WORD;
port->handle_rx(uport, total_bytes, drop);
}

@@ -720,7 +745,7 @@ static void qcom_geni_serial_handle_tx(struct uart_port *uport, bool done,
}

avail = port->tx_fifo_depth - (status & TX_FIFO_WC);
- avail *= port->tx_bytes_pw;
+ avail *= BYTES_PER_FIFO_WORD;

tail = xmit->tail;
chunk = min(avail, pending);
@@ -744,7 +769,7 @@ static void qcom_geni_serial_handle_tx(struct uart_port *uport, bool done,
int c;

memset(buf, 0, ARRAY_SIZE(buf));
- tx_bytes = min_t(size_t, remaining, port->tx_bytes_pw);
+ tx_bytes = min_t(size_t, remaining, BYTES_PER_FIFO_WORD);

for (c = 0; c < tx_bytes ; c++) {
buf[c] = xmit->buf[tail++];
@@ -861,12 +886,6 @@ static int qcom_geni_serial_port_setup(struct uart_port *uport)
u32 proto;
u32 pin_swap;

- if (uart_console(uport))
- port->tx_bytes_pw = 1;
- else
- port->tx_bytes_pw = 4;
- port->rx_bytes_pw = 4;
-
proto = geni_se_read_proto(&port->se);
if (proto != GENI_SE_UART) {
dev_err(uport->dev, "Invalid FW loaded, proto: %d\n", proto);
@@ -898,10 +917,8 @@ static int qcom_geni_serial_port_setup(struct uart_port *uport)
*/
if (uart_console(uport))
qcom_geni_serial_poll_tx_done(uport);
- geni_se_config_packing(&port->se, BITS_PER_BYTE, port->tx_bytes_pw,
- false, true, false);
- geni_se_config_packing(&port->se, BITS_PER_BYTE, port->rx_bytes_pw,
- false, false, true);
+ geni_se_config_packing(&port->se, BITS_PER_BYTE, BYTES_PER_FIFO_WORD,
+ false, true, true);
geni_se_init(&port->se, UART_RX_WM, port->rx_fifo_depth - 2);
geni_se_select_mode(&port->se, GENI_SE_FIFO);
port->setup = true;
@@ -1197,8 +1214,8 @@ static int __init qcom_geni_serial_earlycon_setup(struct earlycon_device *dev,
*/
qcom_geni_serial_poll_tx_done(uport);
qcom_geni_serial_abort_rx(uport);
- geni_se_config_packing(&se, BITS_PER_BYTE, 1, false, true, false);
- geni_se_config_packing(&se, BITS_PER_BYTE, 4, false, false, true);
+ geni_se_config_packing(&se, BITS_PER_BYTE, BYTES_PER_FIFO_WORD,
+ false, true, true);
geni_se_init(&se, DEF_FIFO_DEPTH_WORDS / 2, DEF_FIFO_DEPTH_WORDS - 2);
geni_se_select_mode(&se, GENI_SE_FIFO);

--
2.27.0.212.ge8ba1cc988-goog
\
 
 \ /
  Last update: 2020-06-26 22:02    [W:0.097 / U:0.144 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site