[PATCH v2 1/3] serial: xuartps: Adds RXBS register support for zynqmp
Nava kishore Manne
nava.manne at xilinx.com
Thu Sep 15 02:15:29 PDT 2016
This patch adds RXBS register access support for zynqmp.
To avoid the corner error conditions it will consider only
RXBS[2:0] bits while checking the error conditions
(Parity,Framing and BRAK).
Signed-off-by: Nava kishore Manne <navam at xilinx.com>
---
Changes for v2:
-Initialize 'rxbs_status = 0'
drivers/tty/serial/xilinx_uartps.c | 101 +++++++++++++++++++++++++++++--------
1 file changed, 81 insertions(+), 20 deletions(-)
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 9ca1a4d..527526e 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -57,7 +57,7 @@ MODULE_PARM_DESC(rx_timeout, "Rx timeout, 1-255");
#define CDNS_UART_IMR 0x10 /* Interrupt Mask */
#define CDNS_UART_ISR 0x14 /* Interrupt Status */
#define CDNS_UART_BAUDGEN 0x18 /* Baud Rate Generator */
-#define CDNS_UART_RXTOUT 0x1C /* RX Timeout */
+#define CDNS_UART_RXTOUT 0x1C /* RX Timeout */
#define CDNS_UART_RXWM 0x20 /* RX FIFO Trigger Level */
#define CDNS_UART_MODEMCR 0x24 /* Modem Control */
#define CDNS_UART_MODEMSR 0x28 /* Modem Status */
@@ -68,6 +68,7 @@ MODULE_PARM_DESC(rx_timeout, "Rx timeout, 1-255");
#define CDNS_UART_IRRX_PWIDTH 0x3C /* IR Min Received Pulse Width */
#define CDNS_UART_IRTX_PWIDTH 0x40 /* IR Transmitted pulse Width */
#define CDNS_UART_TXWM 0x44 /* TX FIFO Trigger Level */
+#define CDNS_UART_RXBS 0x48 /* RX FIFO byte status register */
/* Control Register Bit Definitions */
#define CDNS_UART_CR_STOPBRK 0x00000100 /* Stop TX break */
@@ -79,6 +80,9 @@ MODULE_PARM_DESC(rx_timeout, "Rx timeout, 1-255");
#define CDNS_UART_CR_TXRST 0x00000002 /* TX logic reset */
#define CDNS_UART_CR_RXRST 0x00000001 /* RX logic reset */
#define CDNS_UART_CR_RST_TO 0x00000040 /* Restart Timeout Counter */
+#define CDNS_UART_RXBS_PARITY 0x00000001 /* Parity error status */
+#define CDNS_UART_RXBS_FRAMING 0x00000002 /* Framing error status */
+#define CDNS_UART_RXBS_BRK 0x00000004 /* Overrun error status */
/*
* Mode Register:
@@ -131,8 +135,9 @@ MODULE_PARM_DESC(rx_timeout, "Rx timeout, 1-255");
CDNS_UART_IXR_TOUT)
/* Goes in read_status_mask for break detection as the HW doesn't do it*/
-#define CDNS_UART_IXR_BRK 0x80000000
+#define CDNS_UART_IXR_BRK 0x00002000
+#define CDNS_UART_RXBS_SUPPORT BIT(1)
/*
* Modem Control register:
* The read/write Modem Control register controls the interface with the modem
@@ -172,18 +177,29 @@ struct cdns_uart {
struct clk *pclk;
unsigned int baud;
struct notifier_block clk_rate_change_nb;
+ u32 quirks;
+};
+struct cdns_platform_data {
+ u32 quirks;
};
#define to_cdns_uart(_nb) container_of(_nb, struct cdns_uart, \
clk_rate_change_nb);
static void cdns_uart_handle_rx(struct uart_port *port, unsigned int isrstatus)
{
+ struct cdns_uart *cdns_uart = port->private_data;
+ bool is_rxbs_support;
+ unsigned int rxbs_status = 0;
+ unsigned int status_mask;
+
+ is_rxbs_support = cdns_uart->quirks & CDNS_UART_RXBS_SUPPORT;
+
/*
* There is no hardware break detection, so we interpret framing
* error with all-zeros data as a break sequence. Most of the time,
* there's another non-zero byte at the end of the sequence.
*/
- if (isrstatus & CDNS_UART_IXR_FRAMING) {
+ if (!is_rxbs_support && (isrstatus & CDNS_UART_IXR_FRAMING)) {
while (!(readl(port->membase + CDNS_UART_SR) &
CDNS_UART_SR_RXEMPTY)) {
if (!readl(port->membase + CDNS_UART_FIFO)) {
@@ -200,6 +216,8 @@ static void cdns_uart_handle_rx(struct uart_port *port, unsigned int isrstatus)
isrstatus &= port->read_status_mask;
isrstatus &= ~port->ignore_status_mask;
+ status_mask = port->read_status_mask;
+ status_mask &= ~port->ignore_status_mask;
if (!(isrstatus & (CDNS_UART_IXR_TOUT | CDNS_UART_IXR_RXTRIG)))
return;
@@ -208,6 +226,9 @@ static void cdns_uart_handle_rx(struct uart_port *port, unsigned int isrstatus)
u32 data;
char status = TTY_NORMAL;
+ if (is_rxbs_support)
+ rxbs_status = readl(port->membase + CDNS_UART_RXBS);
+
data = readl(port->membase + CDNS_UART_FIFO);
/* Non-NULL byte after BREAK is garbage (99%) */
@@ -217,21 +238,41 @@ static void cdns_uart_handle_rx(struct uart_port *port, unsigned int isrstatus)
if (uart_handle_break(port))
continue;
}
+ if (is_rxbs_support && (rxbs_status & CDNS_UART_RXBS_BRK)) {
+ port->icount.brk++;
+ status = TTY_BREAK;
+ if (uart_handle_break(port))
+ continue;
+ }
if (uart_handle_sysrq_char(port, data))
continue;
port->icount.rx++;
- if (isrstatus & CDNS_UART_IXR_PARITY) {
- port->icount.parity++;
- status = TTY_PARITY;
- } else if (isrstatus & CDNS_UART_IXR_FRAMING) {
- port->icount.frame++;
- status = TTY_FRAME;
- } else if (isrstatus & CDNS_UART_IXR_OVERRUN) {
- port->icount.overrun++;
+ if (is_rxbs_support) {
+ if ((rxbs_status & CDNS_UART_RXBS_PARITY)
+ && (status_mask & CDNS_UART_IXR_PARITY)) {
+ port->icount.parity++;
+ status = TTY_PARITY;
+ }
+ if ((rxbs_status & CDNS_UART_RXBS_FRAMING)
+ && (status_mask & CDNS_UART_IXR_PARITY)) {
+ port->icount.frame++;
+ status = TTY_FRAME;
+ }
+ } else {
+ if (isrstatus & CDNS_UART_IXR_PARITY) {
+ port->icount.parity++;
+ status = TTY_PARITY;
+ }
+ if (isrstatus & CDNS_UART_IXR_FRAMING) {
+ port->icount.frame++;
+ status = TTY_FRAME;
+ }
}
+ if (isrstatus & CDNS_UART_IXR_OVERRUN)
+ port->icount.overrun++;
uart_insert_char(port, isrstatus, CDNS_UART_IXR_OVERRUN,
data, status);
@@ -736,10 +777,14 @@ static void cdns_uart_set_termios(struct uart_port *port,
*/
static int cdns_uart_startup(struct uart_port *port)
{
+ struct cdns_uart *cdns_uart = port->private_data;
+ bool is_brk_support;
int ret;
unsigned long flags;
unsigned int status = 0;
+ is_brk_support = cdns_uart->quirks & CDNS_UART_RXBS_SUPPORT;
+
spin_lock_irqsave(&port->lock, flags);
/* Disable the TX and RX */
@@ -794,7 +839,11 @@ static int cdns_uart_startup(struct uart_port *port)
}
/* Set the Interrupt Registers with desired interrupts */
- writel(CDNS_UART_RX_IRQS, port->membase + CDNS_UART_IER);
+ if (is_brk_support)
+ writel(CDNS_UART_RX_IRQS | CDNS_UART_IXR_BRK,
+ port->membase + CDNS_UART_IER);
+ else
+ writel(CDNS_UART_RX_IRQS, port->membase + CDNS_UART_IER);
return 0;
}
@@ -1328,6 +1377,18 @@ static int cdns_uart_resume(struct device *device)
static SIMPLE_DEV_PM_OPS(cdns_uart_dev_pm_ops, cdns_uart_suspend,
cdns_uart_resume);
+static const struct cdns_platform_data zynqmp_uart_def = {
+ .quirks = CDNS_UART_RXBS_SUPPORT, };
+
+/* Match table for of_platform binding */
+static const struct of_device_id cdns_uart_of_match[] = {
+ { .compatible = "xlnx,xuartps", },
+ { .compatible = "cdns,uart-r1p8", },
+ { .compatible = "cdns,uart-r1p12", .data = &zynqmp_uart_def },
+ {}
+};
+MODULE_DEVICE_TABLE(of, cdns_uart_of_match);
+
/**
* cdns_uart_probe - Platform driver probe
* @pdev: Pointer to the platform device structure
@@ -1340,12 +1401,20 @@ static int cdns_uart_probe(struct platform_device *pdev)
struct uart_port *port;
struct resource *res;
struct cdns_uart *cdns_uart_data;
+ const struct of_device_id *match;
cdns_uart_data = devm_kzalloc(&pdev->dev, sizeof(*cdns_uart_data),
GFP_KERNEL);
if (!cdns_uart_data)
return -ENOMEM;
+ match = of_match_node(cdns_uart_of_match, pdev->dev.of_node);
+ if (match && match->data) {
+ const struct cdns_platform_data *data = match->data;
+
+ cdns_uart_data->quirks = data->quirks;
+ }
+
cdns_uart_data->pclk = devm_clk_get(&pdev->dev, "pclk");
if (IS_ERR(cdns_uart_data->pclk)) {
cdns_uart_data->pclk = devm_clk_get(&pdev->dev, "aper_clk");
@@ -1471,14 +1540,6 @@ static int cdns_uart_remove(struct platform_device *pdev)
return rc;
}
-/* Match table for of_platform binding */
-static const struct of_device_id cdns_uart_of_match[] = {
- { .compatible = "xlnx,xuartps", },
- { .compatible = "cdns,uart-r1p8", },
- {}
-};
-MODULE_DEVICE_TABLE(of, cdns_uart_of_match);
-
static struct platform_driver cdns_uart_platform_driver = {
.probe = cdns_uart_probe,
.remove = cdns_uart_remove,
--
2.1.2
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