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path: root/drivers/tty/serial/8250/8250_omap.c
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Diffstat (limited to 'drivers/tty/serial/8250/8250_omap.c')
-rw-r--r--drivers/tty/serial/8250/8250_omap.c263
1 files changed, 182 insertions, 81 deletions
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index 76fe72bfb8bb..16cfb887c5a3 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -40,6 +40,7 @@
* The same errata is applicable to AM335x and DRA7x processors too.
*/
#define UART_ERRATA_CLOCK_DISABLE (1 << 3)
+#define UART_HAS_EFR2 BIT(4)
#define OMAP_UART_FCR_RX_TRIG 6
#define OMAP_UART_FCR_TX_TRIG 4
@@ -93,6 +94,10 @@
#define OMAP_UART_REV_52 0x0502
#define OMAP_UART_REV_63 0x0603
+/* Enhanced features register 2 */
+#define UART_OMAP_EFR2 0x23
+#define UART_OMAP_EFR2_TIMEOUT_BEHAVE BIT(6)
+
struct omap8250_priv {
int line;
u8 habit;
@@ -105,6 +110,8 @@ struct omap8250_priv {
u8 delayed_restore;
u16 quot;
+ u8 tx_trigger;
+ u8 rx_trigger;
bool is_suspending;
int wakeirq;
int wakeups_enabled;
@@ -118,6 +125,17 @@ struct omap8250_priv {
bool throttled;
};
+struct omap8250_dma_params {
+ u32 rx_size;
+ u8 rx_trigger;
+ u8 tx_trigger;
+};
+
+struct omap8250_platdata {
+ struct omap8250_dma_params *dma_params;
+ u8 habit;
+};
+
#ifdef CONFIG_SERIAL_8250_DMA
static void omap_8250_rx_dma_flush(struct uart_8250_port *p);
#else
@@ -295,8 +313,8 @@ static void omap8250_restore_regs(struct uart_8250_port *up)
serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_RESTORE(16) |
OMAP_UART_TCR_HALT(52));
serial_out(up, UART_TI752_TLR,
- TRIGGER_TLR_MASK(TX_TRIGGER) << UART_TI752_TLR_TX |
- TRIGGER_TLR_MASK(RX_TRIGGER) << UART_TI752_TLR_RX);
+ TRIGGER_TLR_MASK(priv->tx_trigger) << UART_TI752_TLR_TX |
+ TRIGGER_TLR_MASK(priv->rx_trigger) << UART_TI752_TLR_RX);
serial_out(up, UART_LCR, 0);
@@ -435,8 +453,8 @@ static void omap_8250_set_termios(struct uart_port *port,
* This is because threshold and trigger values are the same.
*/
up->fcr = UART_FCR_ENABLE_FIFO;
- up->fcr |= TRIGGER_FCR_MASK(TX_TRIGGER) << OMAP_UART_FCR_TX_TRIG;
- up->fcr |= TRIGGER_FCR_MASK(RX_TRIGGER) << OMAP_UART_FCR_RX_TRIG;
+ up->fcr |= TRIGGER_FCR_MASK(priv->tx_trigger) << OMAP_UART_FCR_TX_TRIG;
+ up->fcr |= TRIGGER_FCR_MASK(priv->rx_trigger) << OMAP_UART_FCR_RX_TRIG;
priv->scr = OMAP_UART_SCR_RX_TRIG_GRANU1_MASK | OMAP_UART_SCR_TX_EMPTY |
OMAP_UART_SCR_TX_TRIG_GRANU1_MASK;
@@ -651,7 +669,7 @@ static int omap_8250_startup(struct uart_port *port)
priv->wer |= OMAP_UART_TX_WAKEUP_EN;
serial_out(up, UART_OMAP_WER, priv->wer);
- if (up->dma)
+ if (up->dma && !(priv->habit & UART_HAS_EFR2))
up->dma->rx_dma(up);
pm_runtime_mark_last_busy(port->dev);
@@ -676,6 +694,8 @@ static void omap_8250_shutdown(struct uart_port *port)
pm_runtime_get_sync(port->dev);
serial_out(up, UART_OMAP_WER, 0);
+ if (priv->habit & UART_HAS_EFR2)
+ serial_out(up, UART_OMAP_EFR2, 0x0);
up->ier = 0;
serial_out(up, UART_IER, 0);
@@ -699,14 +719,12 @@ static void omap_8250_shutdown(struct uart_port *port)
static void omap_8250_throttle(struct uart_port *port)
{
struct omap8250_priv *priv = port->private_data;
- struct uart_8250_port *up = up_to_u8250p(port);
unsigned long flags;
pm_runtime_get_sync(port->dev);
spin_lock_irqsave(&port->lock, flags);
- up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
- serial_out(up, UART_IER, up->ier);
+ port->ops->stop_rx(port);
priv->throttled = true;
spin_unlock_irqrestore(&port->lock, flags);
@@ -714,36 +732,6 @@ static void omap_8250_throttle(struct uart_port *port)
pm_runtime_put_autosuspend(port->dev);
}
-static int omap_8250_rs485_config(struct uart_port *port,
- struct serial_rs485 *rs485)
-{
- struct uart_8250_port *up = up_to_u8250p(port);
-
- /* Clamp the delays to [0, 100ms] */
- rs485->delay_rts_before_send = min(rs485->delay_rts_before_send, 100U);
- rs485->delay_rts_after_send = min(rs485->delay_rts_after_send, 100U);
-
- port->rs485 = *rs485;
-
- /*
- * Both serial8250_em485_init and serial8250_em485_destroy
- * are idempotent
- */
- if (rs485->flags & SER_RS485_ENABLED) {
- int ret = serial8250_em485_init(up);
-
- if (ret) {
- rs485->flags &= ~SER_RS485_ENABLED;
- port->rs485.flags &= ~SER_RS485_ENABLED;
- }
- return ret;
- }
-
- serial8250_em485_destroy(up);
-
- return 0;
-}
-
static void omap_8250_unthrottle(struct uart_port *port)
{
struct omap8250_priv *priv = port->private_data;
@@ -757,6 +745,7 @@ static void omap_8250_unthrottle(struct uart_port *port)
if (up->dma)
up->dma->rx_dma(up);
up->ier |= UART_IER_RLSI | UART_IER_RDI;
+ port->read_status_mask |= UART_LSR_DR;
serial_out(up, UART_IER, up->ier);
spin_unlock_irqrestore(&port->lock, flags);
@@ -767,32 +756,50 @@ static void omap_8250_unthrottle(struct uart_port *port)
#ifdef CONFIG_SERIAL_8250_DMA
static int omap_8250_rx_dma(struct uart_8250_port *p);
+/* Must be called while priv->rx_dma_lock is held */
static void __dma_rx_do_complete(struct uart_8250_port *p)
{
- struct omap8250_priv *priv = p->port.private_data;
struct uart_8250_dma *dma = p->dma;
struct tty_port *tty_port = &p->port.state->port;
+ struct dma_chan *rxchan = dma->rxchan;
+ dma_cookie_t cookie;
struct dma_tx_state state;
int count;
- unsigned long flags;
int ret;
- spin_lock_irqsave(&priv->rx_dma_lock, flags);
-
if (!dma->rx_running)
- goto unlock;
+ goto out;
+ cookie = dma->rx_cookie;
dma->rx_running = 0;
- dmaengine_tx_status(dma->rxchan, dma->rx_cookie, &state);
+ dmaengine_tx_status(rxchan, cookie, &state);
+
+ count = dma->rx_size - state.residue + state.in_flight_bytes;
+ if (count < dma->rx_size) {
+ dmaengine_terminate_async(rxchan);
+
+ /*
+ * Poll for teardown to complete which guarantees in
+ * flight data is drained.
+ */
+ if (state.in_flight_bytes) {
+ int poll_count = 25;
- count = dma->rx_size - state.residue;
+ while (dmaengine_tx_status(rxchan, cookie, NULL) &&
+ poll_count--)
+ cpu_relax();
+ if (!poll_count)
+ dev_err(p->port.dev, "teardown incomplete\n");
+ }
+ }
+ if (!count)
+ goto out;
ret = tty_insert_flip_string(tty_port, dma->rx_buf, count);
p->port.icount.rx += ret;
p->port.icount.buf_overrun += count - ret;
-unlock:
- spin_unlock_irqrestore(&priv->rx_dma_lock, flags);
+out:
tty_flip_buffer_push(tty_port);
}
@@ -818,8 +825,12 @@ static void __dma_rx_complete(void *param)
return;
}
__dma_rx_do_complete(p);
- if (!priv->throttled)
- omap_8250_rx_dma(p);
+ if (!priv->throttled) {
+ p->ier |= UART_IER_RLSI | UART_IER_RDI;
+ serial_out(p, UART_IER, p->ier);
+ if (!(priv->habit & UART_HAS_EFR2))
+ omap_8250_rx_dma(p);
+ }
spin_unlock_irqrestore(&p->port.lock, flags);
}
@@ -845,10 +856,8 @@ static void omap_8250_rx_dma_flush(struct uart_8250_port *p)
if (WARN_ON_ONCE(ret))
priv->rx_dma_broken = true;
}
- spin_unlock_irqrestore(&priv->rx_dma_lock, flags);
-
__dma_rx_do_complete(p);
- dmaengine_terminate_all(dma->rxchan);
+ spin_unlock_irqrestore(&priv->rx_dma_lock, flags);
}
static int omap_8250_rx_dma(struct uart_8250_port *p)
@@ -864,8 +873,20 @@ static int omap_8250_rx_dma(struct uart_8250_port *p)
spin_lock_irqsave(&priv->rx_dma_lock, flags);
- if (dma->rx_running)
+ if (dma->rx_running) {
+ enum dma_status state;
+
+ state = dmaengine_tx_status(dma->rxchan, dma->rx_cookie, NULL);
+ if (state == DMA_COMPLETE) {
+ /*
+ * Disable RX interrupts to allow RX DMA completion
+ * callback to run.
+ */
+ p->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
+ serial_out(p, UART_IER, p->ier);
+ }
goto out;
+ }
desc = dmaengine_prep_slave_single(dma->rxchan, dma->rx_addr,
dma->rx_size, DMA_DEV_TO_MEM,
@@ -1036,6 +1057,46 @@ static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir)
return omap_8250_rx_dma(up);
}
+static unsigned char omap_8250_handle_rx_dma(struct uart_8250_port *up,
+ u8 iir, unsigned char status)
+{
+ if ((status & (UART_LSR_DR | UART_LSR_BI)) &&
+ (iir & UART_IIR_RDI)) {
+ if (handle_rx_dma(up, iir)) {
+ status = serial8250_rx_chars(up, status);
+ omap_8250_rx_dma(up);
+ }
+ }
+
+ return status;
+}
+
+static void am654_8250_handle_rx_dma(struct uart_8250_port *up, u8 iir,
+ unsigned char status)
+{
+ /*
+ * Queue a new transfer if FIFO has data.
+ */
+ if ((status & (UART_LSR_DR | UART_LSR_BI)) &&
+ (up->ier & UART_IER_RDI)) {
+ omap_8250_rx_dma(up);
+ serial_out(up, UART_OMAP_EFR2, UART_OMAP_EFR2_TIMEOUT_BEHAVE);
+ } else if ((iir & 0x3f) == UART_IIR_RX_TIMEOUT) {
+ /*
+ * Disable RX timeout, read IIR to clear
+ * current timeout condition, clear EFR2 to
+ * periodic timeouts, re-enable interrupts.
+ */
+ up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
+ serial_out(up, UART_IER, up->ier);
+ omap_8250_rx_dma_flush(up);
+ serial_in(up, UART_IIR);
+ serial_out(up, UART_OMAP_EFR2, 0x0);
+ up->ier |= UART_IER_RLSI | UART_IER_RDI;
+ serial_out(up, UART_IER, up->ier);
+ }
+}
+
/*
* This is mostly serial8250_handle_irq(). We have a slightly different DMA
* hoook for RX/TX and need different logic for them in the ISR. Therefore we
@@ -1044,6 +1105,7 @@ static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir)
static int omap_8250_dma_handle_irq(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
+ struct omap8250_priv *priv = up->port.private_data;
unsigned char status;
unsigned long flags;
u8 iir;
@@ -1053,19 +1115,18 @@ static int omap_8250_dma_handle_irq(struct uart_port *port)
iir = serial_port_in(port, UART_IIR);
if (iir & UART_IIR_NO_INT) {
serial8250_rpm_put(up);
- return 0;
+ return IRQ_HANDLED;
}
spin_lock_irqsave(&port->lock, flags);
status = serial_port_in(port, UART_LSR);
- if (status & (UART_LSR_DR | UART_LSR_BI)) {
- if (handle_rx_dma(up, iir)) {
- status = serial8250_rx_chars(up, status);
- omap_8250_rx_dma(up);
- }
- }
+ if (priv->habit & UART_HAS_EFR2)
+ am654_8250_handle_rx_dma(up, iir, status);
+ else
+ status = omap_8250_handle_rx_dma(up, iir, status);
+
serial8250_modem_status(up);
if (status & UART_LSR_THRE && up->dma->tx_err) {
if (uart_tx_stopped(&up->port) ||
@@ -1107,18 +1168,41 @@ static int omap8250_no_handle_irq(struct uart_port *port)
return 0;
}
-static const u8 omap4_habit = UART_ERRATA_CLOCK_DISABLE;
-static const u8 am3352_habit = OMAP_DMA_TX_KICK | UART_ERRATA_CLOCK_DISABLE;
-static const u8 dra742_habit = UART_ERRATA_CLOCK_DISABLE;
+static struct omap8250_dma_params am654_dma = {
+ .rx_size = SZ_2K,
+ .rx_trigger = 1,
+ .tx_trigger = TX_TRIGGER,
+};
+
+static struct omap8250_dma_params am33xx_dma = {
+ .rx_size = RX_TRIGGER,
+ .rx_trigger = RX_TRIGGER,
+ .tx_trigger = TX_TRIGGER,
+};
+
+static struct omap8250_platdata am654_platdata = {
+ .dma_params = &am654_dma,
+ .habit = UART_HAS_EFR2,
+};
+
+static struct omap8250_platdata am33xx_platdata = {
+ .dma_params = &am33xx_dma,
+ .habit = OMAP_DMA_TX_KICK | UART_ERRATA_CLOCK_DISABLE,
+};
+
+static struct omap8250_platdata omap4_platdata = {
+ .dma_params = &am33xx_dma,
+ .habit = UART_ERRATA_CLOCK_DISABLE,
+};
static const struct of_device_id omap8250_dt_ids[] = {
- { .compatible = "ti,am654-uart" },
+ { .compatible = "ti,am654-uart", .data = &am654_platdata, },
{ .compatible = "ti,omap2-uart" },
{ .compatible = "ti,omap3-uart" },
- { .compatible = "ti,omap4-uart", .data = &omap4_habit, },
- { .compatible = "ti,am3352-uart", .data = &am3352_habit, },
- { .compatible = "ti,am4372-uart", .data = &am3352_habit, },
- { .compatible = "ti,dra742-uart", .data = &dra742_habit, },
+ { .compatible = "ti,omap4-uart", .data = &omap4_platdata, },
+ { .compatible = "ti,am3352-uart", .data = &am33xx_platdata, },
+ { .compatible = "ti,am4372-uart", .data = &am33xx_platdata, },
+ { .compatible = "ti,dra742-uart", .data = &omap4_platdata, },
{},
};
MODULE_DEVICE_TABLE(of, omap8250_dt_ids);
@@ -1129,10 +1213,10 @@ static int omap8250_probe(struct platform_device *pdev)
struct resource *irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
struct device_node *np = pdev->dev.of_node;
struct omap8250_priv *priv;
+ const struct omap8250_platdata *pdata;
struct uart_8250_port up;
int ret;
void __iomem *membase;
- const struct of_device_id *id;
if (!regs || !irq) {
dev_err(&pdev->dev, "missing registers or irq\n");
@@ -1187,7 +1271,9 @@ static int omap8250_probe(struct platform_device *pdev)
up.port.shutdown = omap_8250_shutdown;
up.port.throttle = omap_8250_throttle;
up.port.unthrottle = omap_8250_unthrottle;
- up.port.rs485_config = omap_8250_rs485_config;
+ up.port.rs485_config = serial8250_em485_config;
+ up.rs485_start_tx = serial8250_em485_start_tx;
+ up.rs485_stop_tx = serial8250_em485_stop_tx;
up.port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_8250_CONSOLE);
ret = of_alias_get_id(np, "serial");
@@ -1211,9 +1297,9 @@ static int omap8250_probe(struct platform_device *pdev)
priv->wakeirq = irq_of_parse_and_map(np, 1);
- id = of_match_device(of_match_ptr(omap8250_dt_ids), &pdev->dev);
- if (id && id->data)
- priv->habit |= *(u8 *)id->data;
+ pdata = of_device_get_match_data(&pdev->dev);
+ if (pdata)
+ priv->habit |= pdata->habit;
if (!up.port.uartclk) {
up.port.uartclk = DEFAULT_CLK_SPEED;
@@ -1230,6 +1316,7 @@ static int omap8250_probe(struct platform_device *pdev)
spin_lock_init(&priv->rx_dma_lock);
device_init_wakeup(&pdev->dev, true);
+ pm_runtime_enable(&pdev->dev);
pm_runtime_use_autosuspend(&pdev->dev);
/*
@@ -1243,12 +1330,13 @@ static int omap8250_probe(struct platform_device *pdev)
pm_runtime_set_autosuspend_delay(&pdev->dev, -1);
pm_runtime_irq_safe(&pdev->dev);
- pm_runtime_enable(&pdev->dev);
pm_runtime_get_sync(&pdev->dev);
omap_serial_fill_features_erratas(&up, priv);
up.port.handle_irq = omap8250_no_handle_irq;
+ priv->rx_trigger = RX_TRIGGER;
+ priv->tx_trigger = TX_TRIGGER;
#ifdef CONFIG_SERIAL_8250_DMA
/*
* Oh DMA support. If there are no DMA properties in the DT then
@@ -1260,13 +1348,26 @@ static int omap8250_probe(struct platform_device *pdev)
*/
ret = of_property_count_strings(np, "dma-names");
if (ret == 2) {
+ struct omap8250_dma_params *dma_params = NULL;
+
up.dma = &priv->omap8250_dma;
- priv->omap8250_dma.fn = the_no_dma_filter_fn;
- priv->omap8250_dma.tx_dma = omap_8250_tx_dma;
- priv->omap8250_dma.rx_dma = omap_8250_rx_dma;
- priv->omap8250_dma.rx_size = RX_TRIGGER;
- priv->omap8250_dma.rxconf.src_maxburst = RX_TRIGGER;
- priv->omap8250_dma.txconf.dst_maxburst = TX_TRIGGER;
+ up.dma->fn = the_no_dma_filter_fn;
+ up.dma->tx_dma = omap_8250_tx_dma;
+ up.dma->rx_dma = omap_8250_rx_dma;
+ if (pdata)
+ dma_params = pdata->dma_params;
+
+ if (dma_params) {
+ up.dma->rx_size = dma_params->rx_size;
+ up.dma->rxconf.src_maxburst = dma_params->rx_trigger;
+ up.dma->txconf.dst_maxburst = dma_params->tx_trigger;
+ priv->rx_trigger = dma_params->rx_trigger;
+ priv->tx_trigger = dma_params->tx_trigger;
+ } else {
+ up.dma->rx_size = RX_TRIGGER;
+ up.dma->rxconf.src_maxburst = RX_TRIGGER;
+ up.dma->txconf.dst_maxburst = TX_TRIGGER;
+ }
}
#endif
ret = serial8250_register_8250_port(&up);
@@ -1464,7 +1565,7 @@ static int omap8250_runtime_resume(struct device *dev)
if (omap8250_lost_context(up))
omap8250_restore_regs(up);
- if (up->dma && up->dma->rxchan)
+ if (up->dma && up->dma->rxchan && !(priv->habit & UART_HAS_EFR2))
omap_8250_rx_dma(up);
priv->latency = priv->calc_latency;
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-03 00:03:20 +0300